Misplaced Pages

#356643

146-1127: Appearing as practical electronic components in 1962, the earliest LEDs emitted low-intensity infrared (IR) light. Infrared LEDs are used in remote-control circuits, such as those used with a wide variety of consumer electronics. The first visible-light LEDs were of low intensity and limited to red. Early LEDs were often used as indicator lamps, replacing small incandescent bulbs , and in seven-segment displays . Later developments produced LEDs available in visible , ultraviolet (UV), and infrared wavelengths with high, low, or intermediate light output, for instance, white LEDs suitable for room and outdoor lighting. LEDs have also given rise to new types of displays and sensors, while their high switching rates are useful in advanced communications technology with applications as diverse as aviation lighting , fairy lights , strip lights , automotive headlamps , advertising, general lighting , traffic signals , camera flashes, lighted wallpaper , horticultural grow lights , and medical devices. LEDs have many advantages over incandescent light sources, including lower power consumption,

292-714: A Republican member of the Texas House of Representatives , was the Texas Instruments president. Geophysical Service, Inc. became a subsidiary of Texas Instruments. Early in 1988, most of GSI was sold to the Halliburton Company. Texas Instruments exists to create, make, and market useful products and services to satisfy the needs of its customers throughout the world. In 1930, J. Clarence Karcher and Eugene McDermott founded Geophysical Service, an early provider of seismic exploration services to

438-471: A passive missile guidance system , which uses the emission from a target of electromagnetic radiation in the infrared part of the spectrum to track it. Missiles that use infrared seeking are often referred to as "heat-seekers" since infrared (IR) is just below the visible spectrum of light in frequency and is radiated strongly by hot bodies. Many objects such as people, vehicle engines, and aircraft generate and retain heat, and as such, are especially visible in

584-524: A thermographic camera , with the fundamental difference that each pixel contains a full LWIR spectrum. Consequently, chemical identification of the object can be performed without a need for an external light source such as the Sun or the Moon. Such cameras are typically applied for geological measurements, outdoor surveillance and UAV applications. In infrared photography , infrared filters are used to capture

730-461: A thermometer . Slightly more than half of the energy from the Sun was eventually found, through Herschel's studies, to arrive on Earth in the form of infrared. The balance between absorbed and emitted infrared radiation has an important effect on Earth's climate . Infrared radiation is emitted or absorbed by molecules when changing rotational-vibrational movements. It excites vibrational modes in

876-416: A wave and of a particle , the photon . It was long known that fires emit invisible heat ; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discovered that infrared radiation is a type of invisible radiation in the spectrum lower in energy than red light, by means of its effect on

1022-562: A GaAs p-n junction light emitter and an electrically isolated semiconductor photodetector. On August 8, 1962, Biard and Pittman filed a patent titled "Semiconductor Radiant Diode" based on their findings, which described a zinc-diffused p–n junction LED with a spaced cathode contact to allow for efficient emission of infrared light under forward bias . After establishing the priority of their work based on engineering notebooks predating submissions from G.E. Labs, RCA Research Labs, IBM Research Labs, Bell Labs , and Lincoln Lab at MIT ,

1168-600: A chemical and electrical process and then converted back into visible light. Infrared light sources can be used to augment the available ambient light for conversion by night vision devices, increasing in-the-dark visibility without actually using a visible light source. The use of infrared light and night vision devices should not be confused with thermal imaging , which creates images based on differences in surface temperature by detecting infrared radiation ( heat ) that emanates from objects and their surrounding environment. Infrared radiation can be used to remotely determine

1314-482: A continuous sequence of weather to be studied. These infrared pictures can depict ocean eddies or vortices and map currents such as the Gulf Stream, which are valuable to the shipping industry. Fishermen and farmers are interested in knowing land and water temperatures to protect their crops against frost or increase their catch from the sea. Even El Niño phenomena can be spotted. Using color-digitized techniques,

1460-667: A current source of a battery or a pulse generator and with a comparison to a variant, pure, crystal in 1953. Rubin Braunstein of the Radio Corporation of America reported on infrared emission from gallium arsenide (GaAs) and other semiconductor alloys in 1955. Braunstein observed infrared emission generated by simple diode structures using gallium antimonide (GaSb), GaAs, indium phosphide (InP), and silicon-germanium (SiGe) alloys at room temperature and at 77  kelvins . In 1957, Braunstein further demonstrated that

1606-554: A glass window or lens to let the light out. Modern indicator LEDs are packed in transparent molded plastic cases, tubular or rectangular in shape, and often tinted to match the device color. Infrared devices may be dyed, to block visible light. More complex packages have been adapted for efficient heat dissipation in high-power LEDs . Surface-mounted LEDs further reduce the package size. LEDs intended for use with fiber optics cables may be provided with an optical connector. The first blue -violet LED, using magnesium-doped gallium nitride

SECTION 10

#1732765832357

1752-442: A leader in the graphing calculator industry. Its defense business was sold to Raytheon Company in 1997; this allowed TI to strengthen its focus on digital solutions. After the acquisition of National Semiconductor in 2011, the company had a combined portfolio of 45,000 analog products and customer design tools. In the stock market, Texas Instruments is often regarded as an indicator for the semiconductor and electronics industry as

1898-568: A longer lifetime, improved physical robustness, smaller sizes, and faster switching. In exchange for these generally favorable attributes, disadvantages of LEDs include electrical limitations to low voltage and generally to DC (not AC) power, the inability to provide steady illumination from a pulsing DC or an AC electrical supply source, and a lesser maximum operating temperature and storage temperature. LEDs are transducers of electricity into light. They operate in reverse of photodiodes , which convert light into electricity. Electroluminescence as

2044-484: A loudspeaker. Intercepting the beam stopped the music. We had a great deal of fun playing with this setup." In September 1961, while working at Texas Instruments in Dallas , Texas , James R. Biard and Gary Pittman discovered near-infrared (900 nm) light emission from a tunnel diode they had constructed on a GaAs substrate. By October 1961, they had demonstrated efficient light emission and signal coupling between

2190-551: A method for producing high-brightness blue LEDs using a new two-step process in 1991. In 2015, a US court ruled that three Taiwanese companies had infringed Moustakas's prior patent, and ordered them to pay licensing fees of not less than US$ 13 million. Two years later, in 1993, high-brightness blue LEDs were demonstrated by Shuji Nakamura of Nichia Corporation using a gallium nitride (GaN) growth process. These LEDs had efficiencies of 10%. In parallel, Isamu Akasaki and Hiroshi Amano of Nagoya University were working on developing

2336-467: A molecule through a change in the dipole moment , making it a useful frequency range for study of these energy states for molecules of the proper symmetry. Infrared spectroscopy examines absorption and transmission of photons in the infrared range. Infrared radiation is used in industrial, scientific, military, commercial, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without

2482-403: A molecule vibrates at a frequency characteristic of that bond. A group of atoms in a molecule (e.g., CH 2 ) may have multiple modes of oscillation caused by the stretching and bending motions of the group as a whole. If an oscillation leads to a change in dipole in the molecule then it will absorb a photon that has the same frequency. The vibrational frequencies of most molecules correspond to

2628-431: A more emissive one. For that reason, incorrect selection of emissivity and not accounting for environmental temperatures will give inaccurate results when using infrared cameras and pyrometers. Infrared is used in night vision equipment when there is insufficient visible light to see. Night vision devices operate through a process involving the conversion of ambient light photons into electrons that are then amplified by

2774-463: A near-IR laser may thus appear dim red and can present a hazard since it may actually be quite bright. Even IR at wavelengths up to 1,050 nm from pulsed lasers can be seen by humans under certain conditions. A commonly used subdivision scheme is: NIR and SWIR together is sometimes called "reflected infrared", whereas MWIR and LWIR is sometimes referred to as "thermal infrared". The International Commission on Illumination (CIE) recommended

2920-529: A paper: "Some Recent Developments in Silicon and Germanium Materials and Devices". In 1954, Texas Instruments designed and manufactured the first transistor radio . The Regency TR-1 used germanium transistors, as silicon transistors were much more expensive at the time. This was an effort by Haggerty to increase market demand for transistors. Jack Kilby , an employee at TI, invented the integrated circuit in 1958. Kilby recorded his initial ideas concerning

3066-520: A phenomenon was discovered in 1907 by the English experimenter Henry Joseph Round of Marconi Labs , using a crystal of silicon carbide and a cat's-whisker detector . Russian inventor Oleg Losev reported the creation of the first LED in 1927. His research was distributed in Soviet, German and British scientific journals, but no practical use was made of the discovery for several decades, partly due to

SECTION 20

#1732765832357

3212-570: A phosphor-silicon mixture on the LED using techniques such as jet dispensing, and allowing the solvents to evaporate, the LEDs are often tested, and placed on tapes for SMT placement equipment for use in LED light bulb production. Some "remote phosphor" LED light bulbs use a single plastic cover with YAG phosphor for one or several blue LEDs, instead of using phosphor coatings on single-chip white LEDs. Ce:YAG phosphors and epoxy in LEDs can degrade with use, and

3358-461: A prototype of the world's first transistor radio , and, through a partnership with Industrial Development Engineering Associates of Indianapolis, Indiana, the 100% solid-state radio was sold to the public beginning in October of that year. In the 1960s, company president Pat Haggerty had a team that included Jack Kilby to work on a handheld calculator project. Kilby and two other colleagues created

3504-503: A red light-emitting diode. GaAsP was the basis for the first wave of commercial LEDs emitting visible light. It was mass produced by the Monsanto and Hewlett-Packard companies and used widely for displays in calculators and wrist watches. M. George Craford , a former graduate student of Holonyak, invented the first yellow LED and improved the brightness of red and red-orange LEDs by a factor of ten in 1972. In 1976, T. P. Pearsall designed

3650-438: A reorganization of Geophysical Service Incorporated , a company founded in 1930 that manufactured equipment for use in the seismic industry, as well as defense electronics. TI produced the world's first commercial silicon transistor in 1954, and the same year designed and manufactured the first transistor radio . Jack Kilby invented the integrated circuit in 1958 while working at TI's Central Research Labs. TI also invented

3796-427: A spectrum of wavelengths, but sometimes only a limited region of the spectrum is of interest because sensors usually collect radiation only within a specific bandwidth. Thermal infrared radiation also has a maximum emission wavelength, which is inversely proportional to the absolute temperature of object, in accordance with Wien's displacement law . The infrared band is often subdivided into smaller sections, although how

3942-507: A trade-off between the luminous efficacy and color rendering. For example, the dichromatic white LEDs have the best luminous efficacy (120 lm/W), but the lowest color rendering capability. Although tetrachromatic white LEDs have excellent color rendering capability, they often have poor luminous efficacy. Trichromatic white LEDs are in between, having both good luminous efficacy (>70 lm/W) and fair color rendering capability. Infrared Infrared ( IR ; sometimes called infrared light )

4088-402: A whole, since the company sells to more than 100,000 customers. Texas Instruments was founded by Cecil H. Green , J. Erik Jonsson , Eugene McDermott , and Patrick E. Haggerty in 1951. McDermott was one of the original founders of Geophysical Service Inc. (GSI) in 1930. McDermott, Green, and Jonsson were GSI employees who purchased the company in 1941. In November 1945, Patrick Haggerty

4234-405: A worldwide scale, this cooling method has been proposed as a way to slow and even reverse global warming , with some estimates proposing a global surface area coverage of 1-2% to balance global heat fluxes. IR data transmission is also employed in short-range communication among computer peripherals and personal digital assistants . These devices usually conform to standards published by IrDA ,

4380-431: Is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves . The infrared spectral band begins with waves that are just longer than those of red light (the longest waves in the visible spectrum ), so IR is invisible to the human eye. IR is generally understood to include wavelengths from around 750  nm (400  THz ) to 1  mm (300  GHz ). IR

4526-411: Is a property of a surface that describes how its thermal emissions deviate from the ideal of a black body . To further explain, two objects at the same physical temperature may not show the same infrared image if they have differing emissivity. For example, for any pre-set emissivity value, objects with higher emissivity will appear hotter, and those with a lower emissivity will appear cooler (assuming, as

Light-emitting diode - Misplaced Pages Continue

4672-451: Is absorbed then re-radiated at longer wavelengths. Visible light or ultraviolet-emitting lasers can char paper and incandescently hot objects emit visible radiation. Objects at room temperature will emit radiation concentrated mostly in the 8 to 25 μm band, but this is not distinct from the emission of visible light by incandescent objects and ultraviolet by even hotter objects (see black body and Wien's displacement law ). Heat

4818-426: Is also a technique called ' T-ray ' imaging, which is imaging using far-infrared or terahertz radiation . Lack of bright sources can make terahertz photography more challenging than most other infrared imaging techniques. Recently T-ray imaging has been of considerable interest due to a number of new developments such as terahertz time-domain spectroscopy . Infrared tracking, also known as infrared homing, refers to

4964-513: Is an American multinational semiconductor company headquartered in Dallas, Texas . It is one of the top 10 semiconductor companies worldwide based on sales volume. The company's focus is on developing analog chips and embedded processors , which account for more than 80% of its revenue. TI also produces digital light processing (DLP) technology and education technology products including calculators , microcontrollers , and multi-core processors . Texas Instruments emerged in 1951 after

5110-430: Is associated with spectra far above the infrared, extending into visible, ultraviolet, and even X-ray regions (e.g. the solar corona ). Thus, the popular association of infrared radiation with thermal radiation is only a coincidence based on typical (comparatively low) temperatures often found near the surface of planet Earth. The concept of emissivity is important in understanding the infrared emissions of objects. This

5256-537: Is being researched as an aid for visually impaired people through the Remote infrared audible signage project. Transmitting IR data from one device to another is sometimes referred to as beaming . IR is sometimes used for assistive audio as an alternative to an audio induction loop . Infrared vibrational spectroscopy (see also near-infrared spectroscopy ) is a technique that can be used to identify molecules by analysis of their constituent bonds. Each chemical bond in

5402-485: Is classified as part of optical astronomy . To form an image, the components of an infrared telescope need to be carefully shielded from heat sources, and the detectors are chilled using liquid helium . The sensitivity of Earth-based infrared telescopes is significantly limited by water vapor in the atmosphere, which absorbs a portion of the infrared radiation arriving from space outside of selected atmospheric windows . This limitation can be partially alleviated by placing

5548-562: Is commonly divided between longer-wavelength thermal IR, emitted from terrestrial sources, and shorter-wavelength IR or near-IR, part of the solar spectrum . Longer IR wavelengths (30–100 μm) are sometimes included as part of the terahertz radiation band. Almost all black-body radiation from objects near room temperature is in the IR band. As a form of electromagnetic radiation, IR carries energy and momentum , exerts radiation pressure , and has properties corresponding to both those of

5694-423: Is counted as part of the microwave band, not infrared, moving the band edge of infrared to 0.1 mm (3 THz). Sunlight , at an effective temperature of 5,780  K (5,510 °C, 9,940 °F), is composed of near-thermal-spectrum radiation that is slightly more than half infrared. At zenith , sunlight provides an irradiance of just over 1  kW per square meter at sea level. Of this energy, 527 W

5840-456: Is defined (according to different standards) at various values typically between 700 nm and 800 nm, but the boundary between visible and infrared light is not precisely defined. The human eye is markedly less sensitive to light above 700 nm wavelength, so longer wavelengths make insignificant contributions to scenes illuminated by common light sources. Particularly intense near-IR light (e.g., from lasers , LEDs or bright daylight with

5986-548: Is difficult but desirable since it takes advantage of existing semiconductor manufacturing infrastructure. It allows for the wafer-level packaging of LED dies resulting in extremely small LED packages. GaN is often deposited using metalorganic vapour-phase epitaxy (MOCVD), and it also uses lift-off . Even though white light can be created using individual red, green and blue LEDs, this results in poor color rendering , since only three narrow bands of wavelengths of light are being emitted. The attainment of high efficiency blue LEDs

Light-emitting diode - Misplaced Pages Continue

6132-485: Is difficult on silicon , while others, like the University of Cambridge, choose a multi-layer structure, in order to reduce (crystal) lattice mismatch and different thermal expansion ratios, to avoid cracking of the LED chip at high temperatures (e.g. during manufacturing), reduce heat generation and increase luminous efficiency. Sapphire substrate patterning can be carried out with nanoimprint lithography . GaN-on-Si

6278-530: Is efficiently detected by inexpensive silicon photodiodes , which the receiver uses to convert the detected radiation to an electric current . That electrical signal is passed through a high-pass filter which retains the rapid pulsations due to the IR transmitter but filters out slowly changing infrared radiation from ambient light. Infrared communications are useful for indoor use in areas of high population density. IR does not penetrate walls and so does not interfere with other devices in adjoining rooms. Infrared

6424-491: Is energy in transit that flows due to a temperature difference. Unlike heat transmitted by thermal conduction or thermal convection , thermal radiation can propagate through a vacuum . Thermal radiation is characterized by a particular spectrum of many wavelengths that are associated with emission from an object, due to the vibration of its molecules at a given temperature. Thermal radiation can be emitted from objects at any wavelength, and at very high temperatures such radiation

6570-401: Is engineered to suit the human eye. Because of metamerism , it is possible to have quite different spectra that appear white. The appearance of objects illuminated by that light may vary as the spectrum varies. This is the issue of color rendition, quite separate from color temperature. An orange or cyan object could appear with the wrong color and much darker as the LED or phosphor does not emit

6716-552: Is especially useful since some radiation at these wavelengths can escape into space through the atmosphere's infrared window . This is how passive daytime radiative cooling (PDRC) surfaces are able to achieve sub-ambient cooling temperatures under direct solar intensity, enhancing terrestrial heat flow to outer space with zero energy consumption or pollution . PDRC surfaces maximize shortwave solar reflectance to lessen heat gain while maintaining strong longwave infrared (LWIR) thermal radiation heat transfer . When imagined on

6862-676: Is infrared radiation, 445 W is visible light, and 32 W is ultraviolet radiation. Nearly all the infrared radiation in sunlight is near infrared, shorter than 4 μm. On the surface of Earth, at far lower temperatures than the surface of the Sun, some thermal radiation consists of infrared in the mid-infrared region, much longer than in sunlight. Black-body, or thermal, radiation is continuous: it radiates at all wavelengths. Of these natural thermal radiation processes, only lightning and natural fires are hot enough to produce much visible energy, and fires produce far more infrared than visible-light energy. In general, objects emit infrared radiation across

7008-750: Is made up of four divisions: analog products , embedded processors , digital light processing , and educational technology . As of January 2021, the industrial market accounts for 41 percent of TI's annual revenue, and the automotive market accounts for 21 percent. TI's remaining businesses consisting of DLP products (primarily used in projectors to create high-definition images), calculators and certain custom semiconductors known as application-specific integrated circuits. Texas Instruments sells DLP technology for TVs, video projectors, and digital cinema . On February 2, 2000, Philippe Binant, technical manager of Digital Cinema Project at Gaumont in France, realized

7154-787: Is more apparent with higher concentrations of Ce:YAG in phosphor-silicone mixtures, because the Ce:YAG decomposes with use. The output of LEDs can shift to yellow over time due to degradation of the silicone. There are several variants of Ce:YAG, and manufacturers in many cases do not reveal the exact composition of their Ce:YAG offerings. Several other phosphors are available for phosphor-converted LEDs to produce several colors such as red, which uses nitrosilicate phosphors, and many other kinds of phosphor materials exist for LEDs such as phosphors based on oxides, oxynitrides, oxyhalides, halides, nitrides, sulfides, quantum dots, and inorganic-organic hybrid semiconductors. A single LED can have several phosphors at

7300-403: Is no universally accepted definition of the range of infrared radiation. Typically, it is taken to extend from the nominal red edge of the visible spectrum at 780 nm to 1 mm. This range of wavelengths corresponds to a frequency range of approximately 430 THz down to 300 GHz. Beyond infrared is the microwave portion of the electromagnetic spectrum . Increasingly, terahertz radiation

7446-457: Is often the case, that the surrounding environment is cooler than the objects being viewed). When an object has less than perfect emissivity, it obtains properties of reflectivity and/or transparency, and so the temperature of the surrounding environment is partially reflected by and/or transmitted through the object. If the object were in a hotter environment, then a lower emissivity object at the same temperature would likely appear to be hotter than

SECTION 50

#1732765832357

7592-530: Is one of the primary parameters studied in research into global warming , together with solar radiation . A pyrgeometer is utilized in this field of research to perform continuous outdoor measurements. This is a broadband infrared radiometer with sensitivity for infrared radiation between approximately 4.5 μm and 50 μm. Astronomers observe objects in the infrared portion of the electromagnetic spectrum using optical components, including mirrors, lenses and solid state digital detectors. For this reason it

7738-596: Is perceived as white light, with improved color rendering compared to wavelengths from the blue LED/YAG phosphor combination. The first white LEDs were expensive and inefficient. The light output then increased exponentially . The latest research and development has been propagated by Japanese manufacturers such as Panasonic and Nichia , and by Korean and Chinese manufacturers such as Samsung , Solstice, Kingsun, Hoyol and others. This trend in increased output has been called Haitz's law after Roland Haitz. Light output and efficiency of blue and near-ultraviolet LEDs rose and

7884-467: Is that low clouds such as stratus or fog can have a temperature similar to the surrounding land or sea surface and do not show up. However, using the difference in brightness of the IR4 channel (10.3–11.5 μm) and the near-infrared channel (1.58–1.64 μm), low clouds can be distinguished, producing a fog satellite picture. The main advantage of infrared is that images can be produced at night, allowing

8030-519: Is that the IR energy heats only opaque objects, such as food, rather than the air around them. Infrared heating is also becoming more popular in industrial manufacturing processes, e.g. curing of coatings, forming of plastics, annealing, plastic welding, and print drying. In these applications, infrared heaters replace convection ovens and contact heating. A variety of technologies or proposed technologies take advantage of infrared emissions to cool buildings or other systems. The LWIR (8–15 μm) region

8176-438: Is the dominant band for long-distance telecommunications networks . The S and L bands are based on less well established technology, and are not as widely deployed. Infrared radiation is popularly known as "heat radiation", but light and electromagnetic waves of any frequency will heat surfaces that absorb them. Infrared light from the Sun accounts for 49% of the heating of Earth, with the rest being caused by visible light that

8322-402: Is the most common way for remote controls to command appliances. Infrared remote control protocols like RC-5 , SIRC , are used to communicate with infrared. Free-space optical communication using infrared lasers can be a relatively inexpensive way to install a communications link in an urban area operating at up to 4 gigabit/s, compared to the cost of burying fiber optic cable, except for

8468-520: Is the spectroscopic wavenumber . It is the frequency divided by the speed of light in vacuum. In the semiconductor industry, infrared light can be used to characterize materials such as thin films and periodic trench structures. By measuring the reflectance of light from the surface of a semiconductor wafer, the index of refraction (n) and the extinction Coefficient (k) can be determined via the Forouhi–Bloomer dispersion equations . The reflectance from

8614-451: Is to use individual LEDs that emit three primary colors —red, green and blue—and then mix all the colors to form white light. The other is to use a phosphor material to convert monochromatic light from a blue or UV LED to broad-spectrum white light, similar to a fluorescent lamp . The yellow phosphor is cerium -doped YAG crystals suspended in the package or coated on the LED. This YAG phosphor causes white LEDs to appear yellow when off, and

8760-404: Is typically in the range 10.3–12.5 μm (IR4 and IR5 channels). Clouds with high and cold tops, such as cyclones or cumulonimbus clouds , are often displayed as red or black, lower warmer clouds such as stratus or stratocumulus are displayed as blue or grey, with intermediate clouds shaded accordingly. Hot land surfaces are shown as dark-grey or black. One disadvantage of infrared imagery

8906-723: The Little Professor in 1976 and Dataman in 1977. TI produces a range of calculators, with the TI-30 being one of the most popular early calculators . TI has also developed a line of graphing calculators , the first being the TI-81 , and most popular being the TI-83 Plus (with the TI-84 Plus being an updated equivalent). Many TI calculators are still sold without graphing capabilities. The TI-30 has been replaced by

SECTION 60

#1732765832357

9052-930: The Nobel Prize in Physics in 2014 for "the invention of efficient blue light-emitting diodes, which has enabled bright and energy-saving white light sources." In 1995, Alberto Barbieri at the Cardiff University Laboratory (GB) investigated the efficiency and reliability of high-brightness LEDs and demonstrated a "transparent contact" LED using indium tin oxide (ITO) on (AlGaInP/GaAs). In 2001 and 2002, processes for growing gallium nitride (GaN) LEDs on silicon were successfully demonstrated. In January 2012, Osram demonstrated high-power InGaN LEDs grown on silicon substrates commercially, and GaN-on-silicon LEDs are in production at Plessey Semiconductors . As of 2017, some manufacturers are using SiC as

9198-535: The Partial Nuclear Test Ban Treaty . Texas Instruments also continued to manufacture equipment for use in the seismic industry, and GSI continued to provide seismic services. After selling (and repurchasing) GSI, TI finally sold the company to Halliburton in 1988, after which sale GSI ceased to exist as a separate entity. In early 1952, Texas Instruments purchased a patent license to produce germanium transistors from Western Electric ,

9344-847: The Paveway series of laser-guided bombs (LGBs). The first LGB was the BOLT-117 . In 1969, TI won the Harpoon (missile) Seeker contract. In 1986, TI won the Army FGM-148 Javelin fire-and-forget man portable antitank guided missile in a joint venture with Martin Marietta . In 1991, TI was awarded the contract for the AGM-154 Joint Standoff Weapon . In 1988, TI paid the U.S. government $ 5.2 million "to settle allegations one of its divisions overcharged

9490-643: The Speak & Spell , such as the Speak & Read and Speak & Math , were introduced soon thereafter. In 1979, TI entered the home computer market with the TI-99/4 , a competitor to computers such as the Apple II , TRS-80 , and the later Atari 400/800 and VIC-20 . By late 1982, TI was dominating the U.S. home computer market, shipping 5,000 computers a day from their factory in Lubbock. It discontinued

9636-793: The TI-99/4A (1981), the sequel to the 99/4, in late 1983 amid an intense price war waged primarily against Commodore. At the 1983 Winter CES, TI showed models 99/2 and the Compact Computer 40 , the latter aimed at professional users. The TI Professional (1983) ultimately joined the ranks of the many unsuccessful MS-DOS and x86 -based—but non-compatible —competitors to the IBM PC (the founders of Compaq , an early leader in PC compatibles, all came from TI). The company for years successfully made and sold PC-compatible laptops before withdrawing from

9782-551: The U.S. patent office issued the two inventors the patent for the GaAs infrared light-emitting diode (U.S. Patent US3293513 ), the first practical LED. Immediately after filing the patent, Texas Instruments (TI) began a project to manufacture infrared diodes. In October 1962, TI announced the first commercial LED product (the SNX-100), which employed a pure GaAs crystal to emit an 890 nm light output. In October 1963, TI announced

9928-455: The human eye as a pure ( saturated ) color. Also unlike most lasers, its radiation is not spatially coherent , so it cannot approach the very high intensity characteristic of lasers . By selection of different semiconductor materials , single-color LEDs can be made that emit light in a narrow band of wavelengths from near-infrared through the visible spectrum and into the ultraviolet range. The required operating voltages of LEDs increase as

10074-557: The $ 1.8 billion in total TI defense revenues, and was sold to TriQuint Semiconductor , Inc. Raytheon retained its own existing MMIC capabilities and has the right to license TI's MMIC technology for use in future product applications from TriQuint. Shortly after Raytheon acquired TI DSEG, Raytheon then acquired Hughes Aircraft from General Motors . Raytheon then owned TI's mercury cadmium telluride detector business and infrared (IR) systems group. In California, it also had Hughes infrared detector and an IR systems business. When again

10220-433: The 1960s, popularized the use of integrated circuits in computer logic. The military-grade version of this was the 5400 series. Texas Instruments invented the hand-held calculator (a prototype called " Cal Tech ") in 1967 and the single-chip microcomputer in 1971, was assigned the first patent on a single-chip microprocessor (invented by Gary Boone) on September 4, 1973. This was disputed by Gilbert Hyatt, formerly of

10366-450: The 3-subpixel model for digital displays. The technology uses a gallium nitride semiconductor that emits light of different frequencies modulated by voltage changes. A prototype display achieved a resolution of 6,800 PPI or 3k x 1.5k pixels. In a light-emitting diode, the recombination of electrons and electron holes in a semiconductor produces light (be it infrared, visible or UV), a process called " electroluminescence ". The wavelength of

10512-504: The Cal-Tech, a three-pound battery-powered calculator that could do basic math and fit six-digit numbers on its display. This 4.25 x 6.15 x 1.75 inch calculator's processor would originate the vast majority of Texas Instruments’ revenue. In 1973, the handheld calculator SR-10 (named after slide rule ) and in 1974, the handheld scientific calculator SR-50 were issued by TI. Both had red LED-segments numeric displays. The optical design of

10658-514: The Defense Systems & Electronics Group (DSEG). During the early 1980s, TI instituted a quality program which included Juran training, as well as promoting statistical process control , Taguchi methods , and Design for Six Sigma . In the late 1980s, the company, along with Eastman Kodak and Allied Signal , began involvement with Motorola , institutionalizing Motorola's Six Sigma methodology. Motorola, which originally developed

10804-564: The Explorer included the gate assignment system for United Airlines, described as "an artificial intelligence program that captures the combined experience and knowledge of a half-dozen United operations experts." In software for the PC, they introduced "Personal Consultant", a rule-based expert system development tool and runtime engine, followed by "Personal Consultant Plus" written in the Lisp-like language from MIT known as Scheme , and

10950-647: The F-22 Radar and Computer development contract. As the defense industry consolidated, TI sold its defense business to the Raytheon Company in 1997 for $ 2.95 billion. The Department of Justice required that Raytheon divest the TI Monolithic Microwave Integrated Circuit (MMIC) operations after closing the transaction. The TI MMIC business accounted for less than $ 40 million in 1996 revenues, or roughly 2% of

11096-535: The IR spectrum is thereby divided varies between different areas in which IR is employed. Infrared radiation is generally considered to begin with wavelengths longer than visible by the human eye. There is no hard wavelength limit to what is visible, as the eye's sensitivity decreases rapidly but smoothly, for wavelengths exceeding about 700 nm. Therefore wavelengths just longer than that can be seen if they are sufficiently bright, though they may still be classified as infrared according to usual definitions. Light from

11242-823: The Industrial Systems Division, which was sold in the early 1990s to Siemens. In 2006, Bain Capital LLC , a private equity firm, purchased the Sensors & Controls division for $ 3.0 billion in cash. The RFID portion of the division remained part of TI, transferring to the Application Specific Products business unit of the Semiconductor division, with the newly formed independent company based in Attleboro taking

11388-488: The Infrared Data Association. Remote controls and IrDA devices use infrared light-emitting diodes (LEDs) to emit infrared radiation that may be concentrated by a lens into a beam that the user aims at the detector. The beam is modulated , i.e. switched on and off, according to a code which the receiver interprets. Usually very near-IR is used (below 800 nm) for practical reasons. This wavelength

11534-678: The Micro Computer Company, in August 1990, when he was awarded a patent superseding TI's. This was overturned on June 19, 1996, in favor of TI (note: Intel is usually given credit with Texas Instruments for the almost-simultaneous invention of the microprocessor). In 1978, Texas Instruments introduced the first single-chip linear predictive coding speech synthesizer . In 1976, TI began a feasibility study of memory-intensive applications for bubble memory then being developed. They soon focused on speech applications. This resulted in

11680-503: The SR-50 is somewhat similar to the HP-35 edited by Hewlett-Packard before in early 1972, but buttons for the operations "+", "–", ... are in the right of the number block and the decimal point lies between two neighboring digits. TI continued to be active in the consumer electronics market through the 1970s and 1980s. Early on, this also included two digital clock models – one for desk and

11826-741: The Six Sigma methodology, began this work in 1982. In 1992, the DSEG division of Texas Instruments' quality-improvement efforts were rewarded by winning the Malcolm Baldrige National Quality Award for manufacturing. TI developed the AAA-4 infrared search and track device in the late 1950s and early 1960s for the F-4B Phantom for passive scanning of jet-engine emissions, but it possessed limited capabilities and

11972-584: The US government forced Raytheon to divest itself of a duplicate capability, the company kept the TI IR systems business and the Hughes detector business. As a result of these acquisitions, these former arch rivals of TI systems and Hughes detectors work together. Immediately after acquisition, DSEG was known as Raytheon TI Systems (RTIS). It is now fully integrated into Raytheon and this designation no longer exists. TI

12118-798: The blending of the colors. Since LEDs have slightly different emission patterns, the color balance may change depending on the angle of view, even if the RGB sources are in a single package, so RGB diodes are seldom used to produce white lighting. Nonetheless, this method has many applications because of the flexibility of mixing different colors, and in principle, this mechanism also has higher quantum efficiency in producing white light. There are several types of multicolor white LEDs: di- , tri- , and tetrachromatic white LEDs. Several key factors that play among these different methods include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency means lower color rendering, presenting

12264-1086: The cladding and quantum well layers for ultraviolet LEDs, but these devices have not yet reached the level of efficiency and technological maturity of InGaN/GaN blue/green devices. If unalloyed GaN is used in this case to form the active quantum well layers, the device emits near-ultraviolet light with a peak wavelength centred around 365 nm. Green LEDs manufactured from the InGaN/GaN system are far more efficient and brighter than green LEDs produced with non-nitride material systems, but practical devices still exhibit efficiency too low for high-brightness applications. With AlGaN and AlGaInN , even shorter wavelengths are achievable. Near-UV emitters at wavelengths around 360–395 nm are already cheap and often encountered, for example, as black light lamp replacements for inspection of anti- counterfeiting UV watermarks in documents and bank notes, and for UV curing . Substantially more expensive, shorter-wavelength diodes are commercially available for wavelengths down to 240 nm. As

12410-555: The company changed its name to Texas Instruments, spun off to build seismographs for oil explorations and with GSI becoming a wholly owned subsidiary of the new company. An early success came for TI-GSI in 1965, when GSI was able (under a Top Secret government contract) to monitor the Soviet Union 's underground nuclear weapons testing under the ocean in Vela Uniform , a subset of Project Vela , to verify compliance of

12556-410: The cost of reliable devices fell. This led to relatively high-power white-light LEDs for illumination, which are replacing incandescent and fluorescent lighting. Experimental white LEDs were demonstrated in 2014 to produce 303 lumens per watt of electricity (lm/W); some can last up to 100,000 hours. Commercially available LEDs have an efficiency of up to 223 lm/W as of 2018. A previous record of 135 lm/W

12702-687: The development the TMC0280 one-chip linear predictive coding speech synthesizer, which was the first time a single silicon chip had electronically replicated the human voice. This was used in several TI commercial products beginning with Speak & Spell , which was introduced at the Summer Consumer Electronics Show in June 1978. In 2001, TI left the speech synthesis business, selling it to Sensory Inc. of Santa Clara, California. In May 1954, Texas Instruments designed and built

12848-539: The division of infrared radiation into the following three bands: ISO 20473 specifies the following scheme: Astronomers typically divide the infrared spectrum as follows: These divisions are not precise and can vary depending on the publication. The three regions are used for observation of different temperature ranges, and hence different environments in space. The most common photometric system used in astronomy allocates capital letters to different spectral regions according to filters used; I, J, H, and K cover

12994-543: The emitted wavelengths become shorter (higher energy, red to blue), because of their increasing semiconductor band gap. Blue LEDs have an active region consisting of one or more InGaN quantum wells sandwiched between thicker layers of GaN, called cladding layers. By varying the relative In/Ga fraction in the InGaN quantum wells, the light emission can in theory be varied from violet to amber. Aluminium gallium nitride (AlGaN) of varying Al/Ga fraction can be used to manufacture

13140-473: The eye is given a moment to adjust to the extremely dim image coming through a visually opaque IR-passing photographic filter, it is possible to see the Wood effect that consists of IR-glowing foliage. In optical communications , the part of the infrared spectrum that is used is divided into seven bands based on availability of light sources, transmitting/absorbing materials (fibers), and detectors: The C-band

13286-493: The field of luminescence with research on radium . Hungarian Zoltán Bay together with György Szigeti patenting a lighting device in Hungary in 1939 based on silicon carbide, with an option on boron carbide, that emitted white, yellowish white, or greenish white depending on impurities present. Kurt Lehovec , Carl Accardo, and Edward Jamgochian explained these first LEDs in 1951 using an apparatus employing SiC crystals with

13432-403: The first terrain-following radar and surveillance radar systems for both the military and FAA. TI demonstrated the first solid-state radar called Molecular Electronics for Radar Applications. In 1976, TI developed a microwave landing system prototype. In 1984, TI developed the first inverse synthetic aperture radar . The first single-chip gallium arsenide radar module was developed. In 1991,

13578-611: The first commercial hemispherical LED, the SNX-110. In the 1960s, several laboratories focused on LEDs that would emit visible light. A particularly important device was demonstrated by Nick Holonyak on October 9, 1962, while he was working for General Electric in Syracuse, New York . The device used the semiconducting alloy gallium phosphide arsenide (GaAsP). It was the first semiconductor laser to emit visible light, albeit at low temperatures. At room temperature it still functioned as

13724-517: The first commercially available blue LED, based on the indirect bandgap semiconductor, silicon carbide (SiC). SiC LEDs had very low efficiency, no more than about 0.03%, but did emit in the blue portion of the visible light spectrum. In the late 1980s, key breakthroughs in GaN epitaxial growth and p-type doping ushered in the modern era of GaN-based optoelectronic devices. Building upon this foundation, Theodore Moustakas at Boston University patented

13870-532: The first digital cinema projection in Europe with the DLP Cinema technology developed by TI DLP technology enables a diverse range of display and advanced light control applications spanning industrial, enterprise, automotive, and consumer market segments. The ASICs business develops more complex integrated-circuit solutions for clients on a custom basis. TI has produced educational toys for children, including

14016-718: The first high-brightness, high-efficiency LEDs for optical fiber telecommunications by inventing new semiconductor materials specifically adapted to optical fiber transmission wavelengths. Until 1968, visible and infrared LEDs were extremely costly, on the order of US$ 200 per unit, and so had little practical use. The first commercial visible-wavelength LEDs used GaAsP semiconductors and were commonly used as replacements for incandescent and neon indicator lamps , and in seven-segment displays , first in expensive equipment such as laboratory and electronics test equipment, then later in such appliances as calculators, TVs, radios, telephones, as well as watches. The Hewlett-Packard company (HP)

14162-473: The fiscal year 2017, Texas Instruments reported earnings of $ 3.682 billion, with an annual revenue of $ 14.961 billion, an increase of 11.9% over the previous fiscal cycle. TI shares traded at over $ 82 per share, and its market capitalization was valued at over $ 88.0 billion in October 2018. As of 2018, TI ranked 192nd on the Fortune 500 list of the largest United States corporations by revenue. As of 2016, TI

14308-499: The frequencies of infrared light. Typically, the technique is used to study organic compounds using light radiation from the mid-infrared, 4,000–400 cm . A spectrum of all the frequencies of absorption in a sample is recorded. This can be used to gain information about the sample composition in terms of chemical groups present and also its purity (for example, a wet sample will show a broad O-H absorption around 3200 cm ). The unit for expressing radiation in this application, cm ,

14454-559: The government on contracts for guided missiles sold to the Navy ". Because of TI's research and development of military temperature-range silicon transistors and integrated circuits (ICs), TI won contracts for the first IC-based computer for the U.S. Air Force in 1961 (molecular electronic computer) and for ICs for the Minuteman Missile the following year. In 1968, TI developed the data systems for Mariner Program . In 1991 TI won

14600-537: The gray-shaded thermal images can be converted to color for easier identification of desired information. The main water vapour channel at 6.40 to 7.08 μm can be imaged by some weather satellites and shows the amount of moisture in the atmosphere. In the field of climatology, atmospheric infrared radiation is monitored to detect trends in the energy exchange between the Earth and the atmosphere. These trends provide information on long-term changes in Earth's climate. It

14746-454: The hand-held calculator in 1967, and introduced the first single-chip microcontroller in 1970, which combined all the elements of computing onto one piece of silicon. In 1987, TI invented the digital light processing device (also known as the DLP chip), which serves as the foundation for the company's DLP technology and DLP Cinema. TI released the popular TI-81 calculator in 1990, which made it

14892-404: The important GaN deposition on sapphire substrates and the demonstration of p-type doping of GaN. This new development revolutionized LED lighting, making high-power blue light sources practical, leading to the development of technologies like Blu-ray . Nakamura was awarded the 2006 Millennium Technology Prize for his invention. Nakamura, Hiroshi Amano , and Isamu Akasaki were awarded

15038-411: The infrared light can also be used to determine the critical dimension, depth, and sidewall angle of high aspect ratio trench structures. Weather satellites equipped with scanning radiometers produce thermal or infrared images, which can then enable a trained analyst to determine cloud heights and types, to calculate land and surface water temperatures, and to locate ocean surface features. The scanning

15184-496: The infrared range of the electromagnetic spectrum (roughly 9,000–14,000 nm or 9–14 μm) and produce images of that radiation. Since infrared radiation is emitted by all objects based on their temperatures, according to the black-body radiation law, thermography makes it possible to "see" one's environment with or without visible illumination. The amount of radiation emitted by an object increases with temperature, therefore thermography allows one to see variations in temperature (hence

15330-412: The infrared wavelengths of light compared to objects in the background. Infrared radiation can be used as a deliberate heating source. For example, it is used in infrared saunas to heat the occupants. It may also be used in other heating applications, such as to remove ice from the wings of aircraft (de-icing). Infrared radiation is used in cooking, known as broiling or grilling . One energy advantage

15476-559: The integrated circuit in July 1958, and successfully demonstrated the world's first working integrated circuit on September 12, 1958. Six months later, Robert Noyce of Fairchild Semiconductor (who went on to co-found Intel ) independently developed the integrated circuit with integrated interconnect, and is also considered an inventor of the integrated circuit. In 1969, Kilby was awarded the National Medal of Science, and in 1982 he

15622-416: The light depends on the energy band gap of the semiconductors used. Since these materials have a high index of refraction, design features of the devices such as special optical coatings and die shape are required to efficiently emit light. Unlike a laser , the light emitted from an LED is neither spectrally coherent nor even highly monochromatic . Its spectrum is sufficiently narrow that it appears to

15768-441: The manufacturing arm of AT&T, for US$ 25,000, beginning production by the end of the year. Haggerty brought Gordon Teal to the company due to his expertise in growing semiconductor crystals while at Bell Telephone Laboratories . Teal's first assignment was to direct TI's research laboratory. At the end of 1952, Texas Instruments announced that it had expanded to 2,000 employees and $ 17 million in sales. Among his new hires

15914-600: The market and selling its product line to Acer in 1998. TI entered the defense electronics market in 1942 with submarine detection equipment, based on the seismic exploration technology previously developed for the oil industry. The division responsible for these products was known at different times as the Laboratory & Manufacturing Division, the Apparatus Division, the Equipment Group, and

16060-473: The military microwave integrated circuit program was initiated—a joint effort with Raytheon. In 1961, TI won the guidance and control system contract for the defense suppression AGM-45 Shrike antiradiation missile . This led later to the prime on the high-speed antiradiation missile (AGM-88 HARM) development contract in 1974 and production in 1981. In 1964, TI began development of the first laser guidance system for precision-guided munitions , leading to

16206-582: The name Sensata Technologies. In 1997, TI sold its software division, along with its main products such as the CA Gen , to Sterling Software , which is now part of Computer Associates . However, TI still owns small pieces of software, such as the software for calculators such as the TI Interactive! . TI also creates a significant amount of target software for its digital signal processors, along with host-based tools for creating DSP applications. For

16352-438: The name). A hyperspectral image is a "picture" containing continuous spectrum through a wide spectral range at each pixel. Hyperspectral imaging is gaining importance in the field of applied spectroscopy particularly with NIR, SWIR, MWIR, and LWIR spectral regions. Typical applications include biological, mineralogical, defence, and industrial measurements. Thermal infrared hyperspectral imaging can be similarly performed using

16498-485: The natural language menu system NLMenu. TI was a major original-equipment manufacturer of sensor , control, protection, and RFID products for the automotive, appliance, aircraft, and other industries. The Sensors & Controls division was headquartered in Attleboro, Massachusetts . By the mid-1980s, industrial computers known as PLC's (programmable logic controllers) were separated from Sensors & Controls as

16644-405: The near-infrared spectrum. Digital cameras often use infrared blockers . Cheaper digital cameras and camera phones have less effective filters and can view intense near-infrared, appearing as a bright purple-white color. This is especially pronounced when taking pictures of subjects near IR-bright areas (such as near a lamp), where the resulting infrared interference can wash out the image. There

16790-446: The near-infrared wavelengths; L, M, N, and Q refer to the mid-infrared region. These letters are commonly understood in reference to atmospheric windows and appear, for instance, in the titles of many papers . A third scheme divides up the band based on the response of various detectors: Near-infrared is the region closest in wavelength to the radiation detectable by the human eye. mid- and far-infrared are progressively further from

16936-431: The observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space such as molecular clouds , to detect objects such as planets , and to view highly red-shifted objects from the early days of the universe . Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, to assist firefighting, and to detect

17082-556: The other a bedside alarm. From this sprang what became the Time Products Division, which made LED watches. Though these LED watches enjoyed early commercial success due to excellent quality, it was short-lived due to poor battery life. LEDs were replaced with LCD watches for a short time, but these could not compete because of styling issues, excessive makes and models, and price points. The watches were manufactured in Dallas and then Lubbock, Texas . Several spin-offs of

17228-506: The overheating of electrical components. Military and civilian applications include target acquisition , surveillance , night vision , homing , and tracking. Humans at normal body temperature radiate chiefly at wavelengths around 10 μm. Non-military uses include thermal efficiency analysis, environmental monitoring, industrial facility inspections, detection of grow-ops , remote temperature sensing, short-range wireless communication , spectroscopy , and weather forecasting . There

17374-422: The petroleum industry. In 1939, the company reorganized as Coronado Corp, an oil company with Geophysical Service Inc (GSI), now as a subsidiary. On December 6, 1941, McDermott along with three other GSI employees, J. Erik Jonsson, Cecil H. Green, and H. B. Peacock purchased GSI. During World War II, GSI expanded its services to include electronics for the U.S. Army , Army Signal Corps , and U.S. Navy . In 1951,

17520-463: The phosphors, the Ce:YAG phosphor converts blue light to green and red (yellow) light, and the PFS phosphor converts blue light to red light. The color, emission spectrum or color temperature of white phosphor converted and other phosphor converted LEDs can be controlled by changing the concentration of several phosphors that form a phosphor blend used in an LED package. The 'whiteness' of the light produced

17666-594: The photosensitivity of microorganisms approximately matches the absorption spectrum of DNA , with a peak at about 260 nm, UV LED emitting at 250–270 nm are expected in prospective disinfection and sterilization devices. Recent research has shown that commercially available UVA LEDs (365 nm) are already effective disinfection and sterilization devices. UV-C wavelengths were obtained in laboratories using aluminium nitride (210 nm), boron nitride (215 nm) and diamond (235 nm). There are two primary ways of producing white light-emitting diodes. One

17812-426: The radiation damage. "Since the eye cannot detect IR, blinking or closing the eyes to help prevent or reduce damage may not happen." Infrared lasers are used to provide the light for optical fiber communications systems. Wavelengths around 1,330 nm (least dispersion ) or 1,550 nm (best transmission) are the best choices for standard silica fibers. IR data transmission of audio versions of printed signs

17958-420: The rudimentary devices could be used for non-radio communication across a short distance. As noted by Kroemer Braunstein "…had set up a simple optical communications link: Music emerging from a record player was used via suitable electronics to modulate the forward current of a GaAs diode. The emitted light was detected by a PbS diode some distance away. This signal was fed into an audio amplifier and played back by

18104-473: The same time. Some LEDs use phosphors made of glass-ceramic or composite phosphor/glass materials. Alternatively, the LED chips themselves can be coated with a thin coating of phosphor-containing material, called a conformal coating. The temperature of the phosphor during operation and how it is applied limits the size of an LED die. Wafer-level packaged white LEDs allow for extremely small LEDs. In 2024, QPixel introduced as polychromatic LED that could replace

18250-408: The space between the crystals allow some blue light to pass through in LEDs with partial phosphor conversion. Alternatively, white LEDs may use other phosphors like manganese(IV)-doped potassium fluorosilicate (PFS) or other engineered phosphors. PFS assists in red light generation, and is used in conjunction with conventional Ce:YAG phosphor. In LEDs with PFS phosphor, some blue light passes through

18396-545: The subsequent device Pankove and Miller built, the first actual gallium nitride light-emitting diode, emitted green light. In 1974 the U.S. Patent Office awarded Maruska, Rhines, and Stanford professor David Stevenson a patent for their work in 1972 (U.S. Patent US3819974 A ). Today, magnesium-doping of gallium nitride remains the basis for all commercial blue LEDs and laser diodes . In the early 1970s, these devices were too dim for practical use, and research into gallium nitride devices slowed. In August 1989, Cree introduced

18542-473: The substrate for LED production, but sapphire is more common, as it has the most similar properties to that of gallium nitride, reducing the need for patterning the sapphire wafer (patterned wafers are known as epi wafers). Samsung , the University of Cambridge , and Toshiba are performing research into GaN on Si LEDs. Toshiba has stopped research, possibly due to low yields. Some opt for epitaxy , which

18688-567: The team at Fairchild led by optoelectronics pioneer Thomas Brandt to achieve the needed cost reductions. LED producers have continued to use these methods as of about 2009. The early red LEDs were bright enough for use as indicators, as the light output was not enough to illuminate an area. Readouts in calculators were so small that plastic lenses were built over each digit to make them legible. Later, other colors became widely available and appeared in appliances and equipment. Early LEDs were packaged in metal cases similar to those of transistors, with

18834-417: The telescope observatory at a high altitude, or by carrying the telescope aloft with a balloon or an aircraft. Space telescopes do not suffer from this handicap, and so outer space is considered the ideal location for infrared astronomy. Texas Instruments 32°54′40″N 96°45′08″W  /  32.9110°N 96.7523°W  / 32.9110; -96.7523 Texas Instruments Incorporated ( TI )

18980-479: The temperature of objects (if the emissivity is known). This is termed thermography, or in the case of very hot objects in the NIR or visible it is termed pyrometry . Thermography (thermal imaging) is mainly used in military and industrial applications but the technology is reaching the public market in the form of infrared cameras on cars due to greatly reduced production costs. Thermographic cameras detect radiation in

19126-459: The very inefficient light-producing properties of silicon carbide, the semiconductor Losev used. In 1936, Georges Destriau observed that electroluminescence could be produced when zinc sulphide (ZnS) powder is suspended in an insulator and an alternating electrical field is applied to it. In his publications, Destriau often referred to luminescence as Losev-Light. Destriau worked in the laboratories of Madame Marie Curie , also an early pioneer in

19272-476: The visible light filtered out) can be detected up to approximately 780 nm, and will be perceived as red light. Intense light sources providing wavelengths as long as 1,050 nm can be seen as a dull red glow, causing some difficulty in near-IR illumination of scenes in the dark (usually this practical problem is solved by indirect illumination). Leaves are particularly bright in the near IR, and if all visible light leaks from around an IR-filter are blocked, and

19418-472: The visible spectrum. Other definitions follow different physical mechanisms (emission peaks, vs. bands, water absorption) and the newest follow technical reasons (the common silicon detectors are sensitive to about 1,050 nm, while InGaAs 's sensitivity starts around 950 nm and ends between 1,700 and 2,600 nm, depending on the specific configuration). No international standards for these specifications are currently available. The onset of infrared

19564-534: The wavelength it reflects. The best color rendition LEDs use a mix of phosphors, resulting in less efficiency and better color rendering. The first white light-emitting diodes (LEDs) were offered for sale in the autumn of 1996. Nichia made some of the first white LEDs which were based on blue LEDs with Ce:YAG phosphor. Ce:YAG is often grown using the Czochralski method . Mixing red, green, and blue sources to produce white light needs electronic circuits to control

19710-418: Was Willis Adcock , who joined TI early in 1953. Adcock, who like Teal was a physical chemist , began leading a small research group focused on the task of fabricating grown-junction, silicon , single-crystal, small-signal transistors. Adcock later became the first TI Principal Fellow. In January 1954, Morris Tanenbaum at Bell Telephone Laboratories created the first workable silicon transistor. This work

19856-607: Was achieved by Nichia in 2010. Compared to incandescent bulbs, this is a huge increase in electrical efficiency, and even though LEDs are more expensive to purchase, overall lifetime cost is significantly cheaper than that of incandescent bulbs. The LED chip is encapsulated inside a small, plastic, white mold although sometimes an LED package can incorporate a reflector. It can be encapsulated using resin ( polyurethane -based), silicone, or epoxy containing (powdered) Cerium-doped YAG phosphor particles. The viscosity of phosphor-silicon mixtures must be carefully controlled. After application of

20002-706: Was active in the area of artificial intelligence in the 1980s. In addition to ongoing developments in speech and signal processing and recognition, it developed and sold the Explorer computer family of Lisp machines . For the Explorer, a special 32-bit Lisp microprocessor was developed, which was used in the Explorer II and the TI MicroExplorer (a Lisp Machine on a NuBus board for the Apple Macintosh ). AI application software developed by TI for

20148-458: Was eliminated on F-4Ds and later models. In 1956, TI began research on infrared technology that led to several line scanner contracts and with the addition of a second scan mirror the invention of the first forward looking infrared (FLIR) in 1963 with production beginning in 1966. In 1972, TI invented the common module FLIR concept, greatly reducing cost and allowing reuse of common components. TI went on to produce side-looking radar systems,

20294-412: Was engaged in research and development (R&D) on practical LEDs between 1962 and 1968, by a research team under Howard C. Borden, Gerald P. Pighini at HP Associates and HP Labs . During this time HP collaborated with Monsanto Company on developing the first usable LED products. The first usable LED products were HP's LED display and Monsanto's LED indicator lamp , both launched in 1968. Monsanto

20440-529: Was hired as general manager of the Laboratory and Manufacturing (L&M) division, which focused on electronic equipment. By 1951, the L&;M division, with its defense contracts, was growing faster than GSI's geophysical division. The company was reorganized and initially renamed General Instruments Inc. Because a firm named General Instrument already existed, the company was renamed Texas Instruments that same year. From 1956 to 1961, Fred Agnich of Dallas, later

20586-504: Was inducted into the National Inventor's Hall of Fame. Kilby also won the 2000 Nobel Prize in Physics for his part of the invention of the integrated circuit. Noyce's chip, made at Fairchild, was made of silicon, while Kilby's chip was made of germanium . In 2008, TI named its new development laboratory "Kilby Labs" after Jack Kilby. The 7400 series of transistor-transistor logic chips, developed by Texas Instruments in

20732-431: Was made at Stanford University in 1972 by Herb Maruska and Wally Rhines , doctoral students in materials science and engineering. At the time Maruska was on leave from RCA Laboratories , where he collaborated with Jacques Pankove on related work. In 1971, the year after Maruska left for Stanford, his RCA colleagues Pankove and Ed Miller demonstrated the first blue electroluminescence from zinc-doped gallium nitride, though

20878-443: Was quickly followed by the development of the first white LED . In this device a Y 3 Al 5 O 12 :Ce (known as " YAG " or Ce:YAG phosphor) cerium -doped phosphor coating produces yellow light through fluorescence . The combination of that yellow with remaining blue light appears white to the eye. Using different phosphors produces green and red light through fluorescence. The resulting mixture of red, green and blue

21024-687: Was reported in the spring of 1954, at the IRE off-the-record conference on solid-state devices, and was later published in the Journal of Applied Physics . Working independently in April 1954, Gordon Teal at TI created the first commercial silicon transistor and tested it on April 14, 1954. On May 10, 1954, at the Institute of Radio Engineers National Conference on Airborne Electronics in Dayton, Ohio, Teal presented

21170-568: Was the first intelligent LED display, and was a revolution in digital display technology, replacing the Nixie tube and becoming the basis for later LED displays. In the 1970s, commercially successful LED devices at less than five cents each were produced by Fairchild Optoelectronics. These devices employed compound semiconductor chips fabricated with the planar process (developed by Jean Hoerni , ). The combination of planar processing for chip fabrication and innovative packaging methods enabled

21316-481: Was the first organization to mass-produce visible LEDs, using Gallium arsenide phosphide (GaAsP) in 1968 to produce red LEDs suitable for indicators. Monsanto had previously offered to supply HP with GaAsP, but HP decided to grow its own GaAsP. In February 1969, Hewlett-Packard introduced the HP Model 5082-7000 Numeric Indicator, the first LED device to use integrated circuit (integrated LED circuit ) technology. It

#356643