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71-483: Autofocus systems rely on one or more sensors to determine correct focus. Some AF systems rely on a single sensor, while others use an array of sensors. Most modern SLR cameras use through-the-lens optical sensors, with a separate sensor array providing light metering , although the latter can be programmed to prioritize its metering to the same area as one or more of the AF sensors. Through-the-lens optical autofocusing

142-461: A CPU ( microprocessor , introduced 1986) and additionally electronically communicate the focus distance information ('D' function, introduced 1992). Therefore, all lenses in this list support all Nikon DSLRs with all camera's exposure and Through-the-lens (TTL) metering modes including Matrix Metering mode, and also flash autoexposure like 3D (Color) Matrix Metering, D-TTL and the newer I-TTL also with Creative Lighting System (CLS). Besides

213-489: A camera based on their previous development at photokina , named Correfot, and in 1978 they displayed an SLR camera with fully operational autofocus. The first mass-produced autofocus camera was the Konica C35 AF , a simple point and shoot model released in 1977. The Polaroid SX-70 Sonar OneStep was the first autofocus single-lens reflex camera , released in 1978. The Pentax ME-F , which used focus sensors in

284-455: A certain degree of illumination to the subject (whether natural or otherwise), while active systems may focus correctly even in total darkness when necessary. Some cameras and external flash units have a special low-level illumination mode (usually orange/red light) which can be activated during auto-focus operation to allow the camera to focus. A method variously referred to as trap focus , focus trap , or catch-in-focus uses autofocus to take

355-447: A certain distance, and where the metal gate is replaced by an ion -sensitive membrane , electrolyte solution and reference electrode . The ISFET is widely used in biomedical applications, such as the detection of DNA hybridization , biomarker detection from blood , antibody detection, glucose measurement, pH sensing, and genetic technology . By the mid-1980s, numerous other MOSFET sensors had been developed, including

426-562: A compact camera, the F300EXR, which included a hybrid autofocus system consisting of both phase-detection and contrast-based elements. The sensors implementing the phase-detection AF in this camera are integrated into the camera's Super CCD EXR. Currently it is used by Fujifilm FinePix Series, Fujifilm X100S , Ricoh , Nikon 1 series , Canon EOS 650D/Rebel T4i and Samsung NX300 . Active systems will typically not focus through windows, since sound waves and infrared light are reflected by

497-471: A digital signal, using an analog-to-digital converter . Since sensors cannot replicate an ideal transfer function , several types of deviations can occur which limit sensor accuracy : All these deviations can be classified as systematic errors or random errors . Systematic errors can sometimes be compensated for by means of some kind of calibration strategy. Noise is a random error that can be reduced by signal processing , such as filtering, usually at

568-551: A few "high-precision" focus points with an additional set of prisms and sensors; they are only active with " fast lenses " with certain geometrical apertures (typically f-number 2.8 and faster). Extended precision comes from the wider effective measurement base of the "range finder" Some modern sensors (for example one in Librem 5 ) include about 2% phase detection pixels on the chip. With suitable software support, that enables phase detection auto focus. Contrast-detection autofocus

639-514: A few dozen wide), some modern cameras ( Canon EOS-1V , Canon EOS-1D , Nikon D2X ) feature TTL area SIR sensors that are rectangular in shape and provide two-dimensional intensity patterns for a finer-grain analysis. Cross-type focus points have a pair of sensors oriented at 90° to one another, although one sensor typically requires a larger aperture to operate than the other. Some cameras ( Minolta 7 , Canon EOS-1V , 1D , 30D / 40D , Pentax K-1 , Sony DSLR-A700 , DSLR-A850 , DSLR-A900 ) also have

710-422: A laser or LED light to the subject and calculating the distance based on the time it takes for the light to travel to the subject and back. This technique is sometimes called laser autofocus , and is present in many mobile phone models from several vendors. It is also present in industrial and medical devices. An exception to the two-step approach is the mechanical autofocus provided in some enlargers, which adjust

781-535: A loss of contrast gives no indication of the direction of motion towards or away from the camera. Contrast-detect autofocus is a common method in digital cameras that lack shutters and reflex mirrors. Most DSLRs use this method (or a hybrid of both contrast and phase-detection autofocus) when focusing in their live-view modes. A notable exception is Canon digital cameras with Dual Pixel CMOS AF. Mirrorless interchangeable-lens cameras typically used contrast-measurement autofocus, although phase detection has become

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852-518: A minimal object contrast to work with. Once this is available, it can work with high accuracy regardless of the speed of a lens; in fact, for as long as this condition is met, it can even work with the lens stopped down. Also, since contrast AF continues to work in stopped-down mode rather than only in open-aperture mode, it is immune to aperture-based focus shift errors phase-detection AF systems suffer since they cannot work in stopped-down mode. Thereby, contrast AF makes arbitrary fine-focus adjustments by

923-480: A sharp distinction between a biosensor and a standard chemical sensor is superfluous. Typical biomimetic materials used in sensor development are molecularly imprinted polymers and aptamers . In biomedicine and biotechnology , sensors which detect analytes thanks to a biological component, such as cells, protein, nucleic acid or biomimetic polymers , are called biosensors . Whereas a non-biological sensor, even organic (carbon chemistry), for biological analytes

994-510: A shot when a subject moves into the focal plane (at the relevant focal point); this can be used to get a focused shot of a rapidly moving object, particularly in sports or wildlife photography , or alternatively to set a "trap" so that a shot can automatically be taken without a person present. This is done by using AF to detect but not set focus – using manual focus to set focus (or switching to manual after focus has been set) but then using focus priority to detect focus and only release

1065-420: A thermometer moves 1  cm when the temperature changes by 1 °C, its sensitivity is 1 cm/°C (it is basically the slope dy/dx assuming a linear characteristic). Some sensors can also affect what they measure; for instance, a room temperature thermometer inserted into a hot cup of liquid cools the liquid while the liquid heats the thermometer. Sensors are usually designed to have a small effect on what

1136-438: Is a self-contained analytical device that can provide information about the chemical composition of its environment, that is, a liquid or a gas phase . The information is provided in the form of a measurable physical signal that is correlated with the concentration of a certain chemical species (termed as analyte ). Two main steps are involved in the functioning of a chemical sensor, namely, recognition and transduction . In

1207-403: Is a wide range of other sensors that measure chemical and physical properties of materials, including optical sensors for refractive index measurement, vibrational sensors for fluid viscosity measurement, and electro-chemical sensors for monitoring pH of fluids. A sensor's sensitivity indicates how much its output changes when the input quantity it measures changes. For instance, if the mercury in

1278-409: Is achieved by dividing the incoming light into pairs of images and comparing them. Through-the-lens secondary image registration (TTL SIR) passive phase detection is often used in film and digital SLR cameras . The system uses a beam splitter (implemented as a small semi-transparent area of the main reflex mirror, coupled with a small secondary mirror) to direct light to an AF sensor at the bottom of

1349-425: Is achieved by measuring contrast (vision) within a sensor field through the lens . The intensity difference between adjacent pixels of the sensor naturally increases with correct image focus. The optical system can thereby be adjusted until the maximal contrast is detected. In this method, AF does not involve actual distance measurement at all. This creates significant challenges when tracking moving subjects , since

1420-469: Is also possible on some Pentax (e.g. K-x and K-5 ), Nikon , and Canon EOS cameras. The EOS 1D can do it using software on an attached computer, whereas cameras like the EOS 40D and 7D have a custom function (III-1 and III-4 respectively) which can stop the camera trying to focus after it fails. On EOS cameras without genuine trap focus, a hack called "almost trap focus" can be used, which achieves some of

1491-415: Is confirmed only when the AF sensor sees an in-focus subject. The only apparent differences between the two modes are that a focus-locking mode halts on focus confirmation, and a continuously focusing mode has predictive elements to work with moving targets, which suggests they are the same closed-loop process. Although AF sensors are typically one-dimensional photosensitive strips (only a few pixels high and

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1562-739: Is measured; making the sensor smaller often improves this and may introduce other advantages. Technological progress allows more and more sensors to be manufactured on a microscopic scale as microsensors using MEMS technology. In most cases, a microsensor reaches a significantly faster measurement time and higher sensitivity compared with macroscopic approaches. Due to the increasing demand for rapid, affordable and reliable information in today's world, disposable sensors—low-cost and easy‐to‐use devices for short‐term monitoring or single‐shot measurements—have recently gained growing importance. Using this class of sensors, critical analytical information can be obtained by anyone, anywhere and at any time, without

1633-403: Is referred to as sensor or nanosensor . This terminology applies for both in-vitro and in vivo applications. The encapsulation of the biological component in biosensors, presents a slightly different problem that ordinary sensors; this can either be done by means of a semipermeable barrier , such as a dialysis membrane or a hydrogel , or a 3D polymer matrix, which either physically constrains

1704-528: Is set to an operation mode that overrides the flash, it may also disable the focus assist. Thus, autofocus may fail to acquire the subject. Similar stroboscopic flashing is sometimes used to reduce the red-eye effect , but this is only intended to constrict the subject's eye pupils before the shot. Some external flash guns have integrated autofocus assist lamps that replace the stroboscopic on-camera flash. Many of them are red and less obtrusive. Another way to assist contrast based AF systems in low light

1775-570: Is the basis for modern image sensors , including the charge-coupled device (CCD) and the CMOS active-pixel sensor (CMOS sensor), used in digital imaging and digital cameras . Willard Boyle and George E. Smith developed the CCD in 1969. While researching the MOS process, they realized that an electric charge was the analogy of the magnetic bubble and that it could be stored on a tiny MOS capacitor. As it

1846-467: Is to beam a laser pattern on to the subject. The laser method is commercially called Hologram AF Laser and was used in Sony CyberShot cameras around the year 2003, including Sony's F707, F717 and F828 models. In a hybrid autofocus system, focus is achieved by combining two or more methods, such as: The double effort is typically used to mutually compensate for the intrinsical weaknesses of

1917-657: Is used to control an electromechanical system that adjusts the focus of the optical system. A variation of autofocus is an electronic rangefinder , in which focus data are provided to the operator, but adjustment of the optical system is still performed manually. The speed of the AF system is highly dependent on the widest aperture offered by the lens at the current focal length. F-stops of around f / 2 to f / 2.8 are generally considered best for focusing speed and accuracy. Faster lenses than this (e.g.: f / 1.4 or f / 1.8) typically have very low depth of field, meaning that it takes longer to achieve correct focus, despite

1988-442: Is usually speedier and more precise than manual focus with an ordinary viewfinder, although more precise manual focus can be achieved with special accessories such as focusing magnifiers. Autofocus accuracy within 1/3 of the depth of field (DOF) at the widest aperture of the lens is common in professional AF SLR cameras. Most multi-sensor AF cameras allow manual selection of the active sensor, and many offer automatic selection of

2059-421: Is very fast, since the measurement method provides both information, the amount of offset and the direction, so that the focusing motor can move the lens right into (or close to) focus without additional measurements. Additional measurements on the fly, however, can improve accuracy or help keep track of moving objects. However, the accuracy of phase-detection auto-focus depends on its effective measurement basis. If

2130-641: The Nikon D40 , D40X , D60 , Nikon D3xxx series (the latest model of which is the D3500 ), Nikon D5xxx series (the latest model of which is the D5600 ), all Nikon 1 series cameras with FT1 adapter and the Nikon Z-mount cameras with FTZ adapter. Clearly designated including the necessary autofocus motor are all Nikon Nikkor AF-S (introduced 1996), AF-P (introduced 2015, not compatible with older bodies like

2201-534: The gas sensor FET (GASFET), surface accessible FET (SAFET), charge flow transistor (CFT), pressure sensor FET (PRESSFET), chemical field-effect transistor (ChemFET), reference ISFET (REFET), biosensor FET (BioFET), enzyme-modified FET (ENFET) and immunologically modified FET (IMFET). By the early 2000s, BioFET types such as the DNA field-effect transistor (DNAFET), gene-modified FET (GenFET) and cell-potential BioFET (CPFET) had been developed. MOS technology

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2272-611: The 1985s. The passive phase-detection auto-focus needs some contrast to work with, making it difficult to use in low-light scenarios or on even surfaces. An AF illuminator will illuminate the scene and project contrast patterns onto even surfaces, so that phase-detection auto-focus can work under these conditions as well. A newer form of a hybrid system is the combination of passive phase-detection auto-focus and passive contrast auto-focus, sometimes assisted by active methods, as both methods need some visible contrast to work with. Under their operational conditions, phase-detection auto-focusing

2343-469: The D3200) and the older AF-I (introduced 1992) lenses. Other manufacturers have different or no designations for lenses including a focus motor. All here not listed AF lenses without an autofocus motor do work fully, but lack autofocus-function on these cameras. Instead an electronic rangefinder can be used to find focus. Additionally all lenses in this list from Nikon and other manufacturers do integrate

2414-472: The FA and FA* series lenses from 1991. Their first K AF -mount Pentax lenses with AF had been introduced in 1989. In 1992, Nikon changed back to lens integrated motors with their AF-I and AF-S range of lenses; today their entry-level DSLRs do not have a focus motor in the body due to the availability of motors in all new developed AF-Lenses . Active AF systems measure distance to the subject independently of

2485-405: The accuracy is typically restricted to a rather limited number of steps. Phase-detection autofocus "sees" through window glasses without problems and is much more accurate, but it does not work in low-light conditions or on surfaces without contrasts or with repeating patterns. A very common example of combined usage is the phase-detection auto-focus system used in single-lens reflex cameras since

2556-557: The base, and in innumerable applications of which most people are never aware. With advances in micromachinery and easy-to-use microcontroller platforms, the uses of sensors have expanded beyond the traditional fields of temperature, pressure and flow measurement, for example into MARG sensors . Analog sensors such as potentiometers and force-sensing resistors are still widely used. Their applications include manufacturing and machinery, airplanes and aerospace, cars, medicine, robotics and many other aspects of our day-to-day life. There

2627-404: The camera body and gears in the lens ("screw drive") or through electronic transmission of the drive instruction through contacts in the mount plate to a motor in the lens. Lens-based motors can be of a number of different types, but are often ultrasonic motors or stepper motors . Magnets are often used in electromagnetic motors, such as Voice coil motors (VCMs) and Stepper motor , which move

2698-555: The camera body coupled with a motorized lens , became the first autofocus 35 mm SLR in 1981. In 1983 Nikon released the F3AF , their first autofocus camera, which was based on a similar concept to the ME-F. The Minolta 7000 , released in 1985, was the first SLR with an integrated autofocus system, meaning both the AF sensors and the drive motor were housed in the camera body, as well as an integrated film advance winder — which

2769-437: The camera's autofocus system uses to achieve focus. Many cameras and nearly all camera phones lack a dedicated autofocus assist lamp. Instead, they use their built-in flash, illuminating the subject with bursts of light. This aids the autofocus system in the same fashion as a dedicated assist light, but has the disadvantage of startling or annoying people. Another disadvantage is that if the camera uses flash focus assist and

2840-399: The camera. When in use, the lens will constantly maintain its focus on the subject, hence it is commonly used for sports and action photography . AI refers to artificial intelligence : algorithms that constantly predict where a subject is about to be based on its speed and acceleration data from the autofocus sensor. Modern autofocus is done through one of two mechanisms; either a motor in

2911-416: The camera. Two micro-lenses capture the light rays coming from the opposite sides of the lens and divert it to the AF sensor, creating a simple rangefinder with a base within the lens's diameter. The two images are then analysed for similar light intensity patterns (peaks and valleys) and the separation error is calculated in order to find whether the object is in front focus or back focus position. This gives

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2982-412: The direction and an estimate of the required amount of focus-ring movement. PD AF in a continuously focusing mode (e.g. "AI Servo" for Canon , "AF-C" for Nikon , Pentax and Sony ) is a closed-loop control process. PD AF in a focus-locking mode (e.g. "One-Shot" for Canon , "AF-S" for Nikon and Sony ) is widely believed to be a "one measurement, one movement" open-loop control process, but focus

3053-399: The effects of trap focus. By using the custom firmware Magic Lantern , some Canon DSLRs can perform trap focus. AI Servo is an autofocus mode found on Canon SLR cameras, and in other brands such as Nikon , Sony , and Pentax , under the name "continuous focus" (AF-C). Also referred to as focus tracking , it is used to track a subject as it moves around the frame, or toward and away from

3124-499: The expense of the dynamic behavior of the sensor. The sensor resolution or measurement resolution is the smallest change that can be detected in the quantity that is being measured. The resolution of a sensor with a digital output is usually the numerical resolution of the digital output. The resolution is related to the precision with which the measurement is made, but they are not the same thing. A sensor's accuracy may be considerably worse than its resolution. A chemical sensor

3195-415: The focal range, stopping precisely at the point where maximal contrast is detected. This means that lenses designed for phase detection often perform poorly on camera bodies that use contrast detection. The assist light (also known as AF illuminator) "activates" passive autofocus systems in low-light and low- contrast situations in some cameras. The lamp projects visible or IR light onto the subject, which

3266-495: The glass. With passive systems this will generally not be a problem, unless the window is stained. Accuracy of active autofocus systems is often considerably less than that of passive systems. Active systems may also fail to focus a subject that is very close to the camera (e.g., macro photography ). Passive systems may not find focus when the contrast is low, notably on large single-colored surfaces (walls, blue sky, etc.) or in low-light conditions. Passive systems are dependent on

3337-454: The increased amount of light. Most consumer camera systems will only autofocus reliably with lenses that have a widest aperture of at least f / 5.6, whilst professional models can often cope with a widest aperture of f / 8, which is particularly useful for lenses used in conjunction with teleconverters . Between 1960 and 1973, Leitz (Leica) patented an array of autofocus and corresponding sensor technologies. In 1976, Leica had presented

3408-502: The intrinsical accuracy of the autofocus system, even if fast lenses are used. Since the effective measurement basis is an optical property of the actual implementation, it cannot be changed easily. Very few cameras provide multi-PD-AF systems with several switchable measurement bases depending on the lens used in order to allow normal auto-focusing with most lenses, and more accurate focusing with fast lenses. Contrast AF does not have this inherent design limitation on accuracy as it only needs

3479-565: The latter case, infrared light is usually used to triangulate the distance to the subject. Compact cameras including the Nikon 35TiQD and 28TiQD , the Canon AF35M , and the Contax T2 and T3 , as well as early video cameras, used this system. A newer approach included in some consumer electronic devices, like mobile phones, is based on the time-of-flight principle, which involves shining

3550-494: The lens directly. Passive AF systems determine correct focus by performing passive analysis of the image that is entering the optical system. They generally do not direct any energy, such as ultrasonic sound or infrared light waves, toward the subject. (However, an autofocus assist beam of usually infrared light is required when there is not enough light to take passive measurements.) Passive autofocusing can be achieved by phase detection or contrast measurement. Phase detection (PD)

3621-404: The lens elements to achieve precise focusing. The magnetic field interacts with coils to produce motion for adjusting the lens position quickly and accurately based on focus requirements. Magnets are ideal for this purpose because they enable smooth and rapid adjustments without direct physical contact, enhancing durability and response time. Some camera bodies, including all Canon EOS bodies and

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3692-516: The measurement basis is large, measurements are very accurate, but can only work with lenses with a large geometrical aperture (e.g. 1:2.8 or larger). Even with high contrasty objects, phase-detection AF cannot work at all with lenses slower than its effective measurement basis. In order to work with most lenses, the effective measurement basis is typically set to between 1:5.6 and 1:6.7, so that AF continues to work with slow lenses (at least for as long as they are not stopped down). This, however, reduces

3763-433: The more budget-oriented among Nikon's DX models, do not include an autofocus motor and therefore cannot autofocus with lenses that lack an inbuilt motor. Some lenses, such as Pentax' DA* designated models, although normally using an inbuilt motor, can fall back to screwdrive operation when the camera body does not support the necessary contact pins. Sensor A sensor is a device that produces an output signal for

3834-409: The need for recalibration and worrying about contamination. A good sensor obeys the following rules: Most sensors have a linear transfer function . The sensitivity is then defined as the ratio between the output signal and measured property. For example, if a sensor measures temperature and has a voltage output, the sensitivity is constant with the units [V/K]. The sensitivity is the slope of

3905-412: The norm on most mirrorless cameras giving them significantly better AF tracking performance compared to contrast detection. Contrast detection places different constraints on lens design when compared with phase detection. While phase detection requires the lens to move its focus point quickly and directly to a new position, contrast-detection autofocus instead employs lenses that can quickly sweep through

3976-406: The open-gate field-effect transistor (OGFET) introduced by Johannessen in 1970, the ion-sensitive field-effect transistor (ISFET) invented by Piet Bergveld in 1970, the adsorption FET (ADFET) patented by P.F. Cox in 1974, and a hydrogen -sensitive MOSFET demonstrated by I. Lundstrom, M.S. Shivaraman, C.S. Svenson and L. Lundkvist in 1975. The ISFET is a special type of MOSFET with a gate at

4047-492: The optical system, and subsequently adjust the optical system for correct focus. There are various ways to measure distance, including ultrasonic sound waves and infrared light. In the first case, sound waves are emitted from the camera, and by measuring the delay in their reflection, distance to the subject is calculated. Polaroid cameras including the Spectra and SX-70 were known for successfully applying this system. In

4118-424: The phase-detection AF sensors into the image sensor itself. Typically, these phase-detection sensors are not as accurate as the more sophisticated stand-alone sensors, but since the fine focusing is now carried out through contrast focusing, the phase-detection AF sensors are only need to provide coarse directional information in order to speed up the contrast auto-focusing process. In July, 2010, Fujifilm announced

4189-404: The purpose of detecting a physical phenomenon. In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in its environment and sends the information to other electronics, frequently a computer processor. Sensors are used in everyday objects such as touch-sensitive elevator buttons ( tactile sensor ) and lamps which dim or brighten by touching

4260-473: The quality (autofocus speed and noise, optical aberrations and other) of the lens including the way this quality is achieved (used technologies like type of autofocus motor, lens and body design and others), the main functional differences of the lenses in this list are the integration of optical image stabilization ('VR', introduced 2000) and secondly if it fully illuminates a Nikon FX (full-frame, 35mm ) image sensor format and smaller sizes or if

4331-521: The recognition step, analyte molecules interact selectively with receptor molecules or sites included in the structure of the recognition element of the sensor. Consequently, a characteristic physical parameter varies and this variation is reported by means of an integrated transducer that generates the output signal. A chemical sensor based on recognition material of biological nature is a biosensor . However, as synthetic biomimetic materials are going to substitute to some extent recognition biomaterials,

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4402-665: The sensing macromolecule or chemically constrains the macromolecule by bounding it to the scaffold. Neuromorphic sensors are sensors that physically mimic structures and functions of biological neural entities. One example of this is the event camera . The MOSFET invented at Bell Labs between 1955 and 1960, MOSFET sensors (MOS sensors) were later developed, and they have since been widely used to measure physical , chemical , biological and environmental parameters. A number of MOSFET sensors have been developed, for measuring physical , chemical , biological , and environmental parameters. The earliest MOSFET sensors include

4473-410: The sensor using algorithms which attempt to discern the location of the subject. Some AF cameras are able to detect whether the subject is moving towards or away from the camera, including speed and acceleration, and keep focus — a function used mainly in sports and other action photography. Canon cameras call this AI servo ; Nikon cameras call it "continuous focus". The data collected from AF sensors

4544-484: The shutter when an object is in focus. The technique works by choosing the focus adjustment (turning AF off), then setting the shooting mode to "Single" (AF-S), or more specifically focus priority, then depressing the shutter – when the subject moves into focus, the AF detects this (though it does not change the focus), and a shot is taken. The first SLR to implement trap focusing was the Yashica 230 AF . Trap focus

4615-497: The speed of the focus iteration process is mechanically limited and this measurement method does not provide any directional information. Combining both measurement methods, the phase-detection AF can assist a contrast AF system to be fast and accurate at the same time, to compensate aperture-based focus-shift errors, and to continue to work with lenses stopped down, as, for example, in stopped-down measuring or video mode. Recent developments towards mirrorless cameras seek to integrate

4686-459: The transfer function. Converting the sensor's electrical output (for example V) to the measured units (for example K) requires dividing the electrical output by the slope (or multiplying by its reciprocal). In addition, an offset is frequently added or subtracted. For example, −40 must be added to the output if 0 V output corresponds to −40 C input. For an analog sensor signal to be processed or used in digital equipment, it needs to be converted to

4757-411: The user unnecessary. Also, contrast AF is immune to focusing errors due to surfaces with repeating patterns and they can work over the whole frame, not just near the center of the frame, as phase-detection AF does. The down-side, however, is that contrast AF is a closed-loop iterative process of shifting the focus back and forth in rapid succession. Compared to phase-detection AF, contrast AF is slow, since

4828-412: The various methods in order to increase the overall reliability and accuracy or to speed up AF function. A rare example of an early hybrid system is the combination of an active IR or ultrasonic auto-focus system with a passive phase-detection system. An IR or ultrasonic system based on reflection will work regardless of the light conditions, but can be easily fooled by obstacles like window glasses, and

4899-431: Was fairly straightforward to fabricate a series of MOS capacitors in a row, they connected a suitable voltage to them so that the charge could be stepped along from one to the next. The CCD is a semiconductor circuit that was later used in the first digital video cameras for television broadcasting . The MOS active-pixel sensor (APS) was developed by Tsutomu Nakamura at Olympus in 1985. The CMOS active-pixel sensor

4970-1481: Was later developed by Eric Fossum and his team in the early 1990s. MOS image sensors are widely used in optical mouse technology. The first optical mouse, invented by Richard F. Lyon at Xerox in 1980, used a 5   μm NMOS sensor chip. Since the first commercial optical mouse, the IntelliMouse introduced in 1999, most optical mouse devices use CMOS sensors. MOS monitoring sensors are used for house monitoring , office and agriculture monitoring, traffic monitoring (including car speed , traffic jams , and traffic accidents ), weather monitoring (such as for rain , wind , lightning and storms ), defense monitoring, and monitoring temperature , humidity , air pollution , fire , health , security and lighting . MOS gas detector sensors are used to detect carbon monoxide , sulfur dioxide , hydrogen sulfide , ammonia , and other gas substances. Other MOS sensors include intelligent sensors and wireless sensor network (WSN) technology. List of Nikon F-mount lenses with integrated autofocus motor The following list of Nikon F-mount lenses with integrated autofocus motor includes only Nikon F-mount lenses which fully autofocus in all modes of all Nikon F-mount digital single-lens reflex cameras with and also without an autofocus motor . Cameras lacking an integrated autofocus motor (often called screw drive) are

5041-408: Was to become the standard configuration for SLR cameras from this manufacturer, and also Nikon abandoned their F3AF system and integrated the autofocus-motor and sensors in the body. Canon decided to discontinue their FD mount and switched to the completely electronic EF mount with motorised lenses in 1987. Pentax was the first to introduce focusing distance measurement for SLR cameras with

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