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99-676: LaserJet is a line of laser printers sold by HP Inc. (originally Hewlett-Packard ) since 1984. The LaserJet was the world's first commercially successful laser printer. Canon supplies both mechanisms and cartridges for most HP laser printers; some larger A3 models use Samsung print engines. These printers (and later on all-in-one units, including scanning and faxing) have, as of 2020, a three decade plus history of serving both in offices and at home for personal/at home use. In 2013, Advertising Age reported that HP had "78 different printers with 6 different model names." Most HP LaserJet printers employ xerographic laser-marking engines sourced from

198-574: A DC bias on the drum surface to ensure a uniform negative potential. Numerous patents describe the photosensitive drum coating as a silicon "sandwich" with a photocharging layer, a charge leakage barrier layer, as well as a surface layer. One version uses amorphous silicon containing hydrogen as the light-receiving layer, boron nitride as a charge leakage barrier layer, as well as a surface layer of doped silicon , notably silicon with oxygen or nitrogen which at sufficient concentration resembles machining silicon nitride . A laser printer uses

297-412: A buffer underrun (where the laser reaches a point on the page before it has the dots to draw there), a laser printer typically needs enough raster memory to hold the bitmap image of an entire page. Memory requirements increase with the square of the dots per inch , so 600 dpi requires a minimum of 4 megabytes for monochrome, and 16 megabytes for color (still at 600 dpi). For fully graphical output using

396-481: A corona wire positioned parallel to the drum or, in more recent printers, a primary charge roller, projects an electrostatic charge onto the photoreceptor (otherwise named the photoconductor unit), a revolving photosensitive drum or belt, which is capable of holding an electrostatic charge on its surface while it is in the dark. An AC bias voltage is applied to the primary charge roller to remove any residual charges left by previous images. The roller will also apply

495-411: A parallel ( Centronics ) interface. It also included 512 kilobytes of memory, which was sufficient to print graphics at 300 dpi that covered about 70% of the letter-size page area. The LaserJet IID was released in the fall of 1988, It was the first desktop laser printer capable of duplexing. It was also the first LaserJet with an HP-designed and manufactured formatter. In September 1989, HP introduced

594-637: A raster image , they nonetheless outperform the 1984 LaserJet in nearly all situations. Laser printer speed can vary widely, and depends on many factors, including the graphic intensity of the job being processed. The fastest models can print over 200 monochrome pages per minute (12,000 pages per hour). The fastest color laser printers can print over 100 pages per minute (6000 pages per hour). Very high-speed laser printers are used for mass mailings of personalized documents, such as credit card or utility bills, and are competing with lithography in some commercial applications. The cost of this technology depends on

693-563: A 5Si equipped with all available options, was marketed as the first network printer that was optimized to produce multiple original prints (mopies). It had a 100,000 copies-per-month duty cycle, and 24 ppm print speed. In 1997, HP introduced the LaserJet 4000 family of printers. They included features from the LaserJet 5 plus higher resolution of 1200 dpi. These are mostly used in offices, and most recently in people's homes mainly to replace

792-492: A LaserJet 4 / 4M printer could be connected to a network, for example as a departmental printer in companies instead of the larger III Si and 4 Si models. In 2020 The New York Times wrote "by the 1990s, it was a staple of offices around the world." The flagship of the family was the LaserJet 4 SiMX, launched in May 1993. It had several network interfaces by default, both Ethernet, Appletalk and TokenRing. Instant-on fusing

891-419: A LaserJet is used to emulate a lineprinter. With the advent of the LaserJet 4000 in 1997, the control panel was completely redesigned. The Shift button, which might have been confusing, was gone. There was a Menu , an Item and a Value button. Each of these might be clicked left or right. There was a Select button, a large green Go button, and a small orange Cancel Job button. Configuration through

990-433: A combination of factors, including the cost of paper, toner, drum replacement, as well as the replacement of other items such as the fuser assembly and transfer assembly. Often printers with soft plastic drums can have a very high cost of ownership that does not become apparent until the drum requires replacement. Duplex printing (printing on both sides of the paper) can halve paper costs and reduce filing volumes, albeit at

1089-519: A control system and character generator, resulting in a printer called EARS (Ethernet, Alto Research character generator, Scanned laser output terminal)—which later became the Xerox 9700 laser printer. In 1976, the first commercial implementation of a laser printer, the IBM 3800 , was released. It was designed for data centers , where it replaced line printers attached to mainframe computers . The IBM 3800

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1188-674: A dramatic effect on word processing software market. The LaserJet IIID was the same as the LaserJet III except it had 2 paper trays and duplex printing. It sold for $ 4,995 in the fall of 1990. The first mass-market Ethernet network printer, the LaserJet IIISi, debuted in March 1991. Priced at $ 5,495, it featured a high-speed, 17 ppm engine, 5MB of memory, 300-dpi output, Image REt and such paper handling features as job stacking and optional duplex printing . The LaserJet IIISi also

1287-429: A heated transfer roller instead of a fuser, that melts the charged ink particles before applying them to the paper. Color laser transfer printers are designed to produce transfer media which are transfer sheets designed to be applied by means of a heat press . These transfers are typically used to make custom T-shirts or custom logo products with corporate or team logos on them. 2-part Color laser transfers are part of

1386-405: A laser because lasers are able to form highly focused, precise, and intense beams of light, especially over the short distances inside of a printer. The laser is aimed at a rotating polygonal mirror which directs the light beam through a system of lenses and mirrors onto the photoreceptor drum, writing pixels at rates up to sixty-five million times per second. The drum continues to rotate during

1485-428: A laser printer is somewhat delicate and, once damaged, often impossible to repair. The drum, in particular, is a critical component: it must not be left exposed to ambient light for more than a few hours, as light is what causes it to lose its charge and will eventually wear it out. Anything that interferes with the operation of the laser such as a scrap of torn paper may prevent the laser from discharging some portion of

1584-414: A laser. "Exposing" is also known as "writing" in some documentation. As the drums rotate, toner is continuously applied in a 15- micron -thick layer to the developer roll . The surface of the photoreceptor with the latent image is exposed to the toner-covered developer roll. Toner consists of fine particles of dry plastic powder mixed with carbon black or coloring agents. The toner particles are given

1683-496: A lit error light and a lit ready light would indicate a fuser problem (usually just needs to be reseated – most 4L problems can be resolved by simply disassembling the printer, cleaning it, then reassembling it). This was much more cryptic than the alphanumeric display of earlier models like the II/IID III/IIID, IIP, and IIIP, as it was impossible to determine the meaning of the patterns of LEDs without comparing them against

1782-426: A manual (or having their meaning memorized, which some technicians exposed to them often might actually do, intentionally or not). The 4L used early light pipes, with surface-mounted LEDs on the control board on the left side of the printer, and plastic channels to conduct light from the lit status LEDs to the top of the printer. The LaserJet 4/4 Plus/4M/4M Plus retained an alphanumeric display, and in fact upgraded from

1881-937: A model has been discontinued, manufacturers are no longer obligated to produce new parts to repair printers. HP has generally continued to produce parts after this time to continue support for their LaserJet printers, but as of 2017 there are a number of models for which new parts are no longer available from the original manufacturer: Mono: 1100, 1150, 1160, 1200, 1300, 1320, 2100, 2300, 3015, 3020, 3030, 3050, 3052, 3055, 3100, 3150, 3200, 3300, 3310, 3320, 3330, 3380, 3390, 4, 4+, 4000, 4050, 4100, 5, 5+, 5si, 5000, 5100, 6, 6L, 6P, 8150, 9000, M1522, M2727; Color: 1500, 1600, 2500, 2550, 2600, 2820, 2840, 3500, 3550, 3600, 3700, 3800, 4500, 4550, 4600, 4650, 8500, 8550, 9500, 9550, CM4730, CP3505. Third-party maintenance companies may have limited supplies of parts from their own stocks or from cannibalized equipment, but eventually recommend migrating to newer equipment. Laser printer The laser printer

1980-538: A nearly invisible dot raster , for the purpose of traceability. The dots are yellow and about 0.1 mm (0.0039 in) in size, with a raster of about 1 mm (0.039 in). This is purportedly the result of a deal between the US government and printer manufacturers to help track counterfeiters . The dots encode data such as printing date, time, and printer serial number in binary-coded decimal on every sheet of paper printed, which allows pieces of paper to be traced by

2079-445: A negative charge inside the toner cartridge , and as they emerge onto the developer drum they are electrostatically attracted to the photoreceptor's latent image (the areas on the surface of the drum which had been struck by the laser). Because negative charges repel each other, the negatively charged toner particles will not adhere to the drum where the negative charge (imparted previously by the charge roller) remains. A sheet of paper

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2178-474: A new job is sent to it, or if sending of a job in progress is resumed. Also, the "Online" button is actually a toggle switch, such that if the printer is already online, pressing Online makes the printer go offline and can be used to stop a runaway print job. Pressing Shift-Reset will then reset the printer, clearing the remainder of the unwanted document from the printer's memory, so that it will not continue to print it when brought back on line. (Before resetting

2277-513: A page description language, a minimum of 1 megabyte of memory is needed to store an entire monochrome letter - or A4 -sized page of dots at 300 dpi. At 300 dpi, there are 90,000 dots per square inch (300 dots per linear inch). A typical 8.5 × 11 sheet of paper has 0.25-inch (6.4 mm) margins, reducing the printable area to 8.0 by 10.5 inches (200 mm × 270 mm), or 84 square inches. 84 sq/in × 90,000 dots per sq/in = 7,560,000 dots. 1 megabyte = 1,048,576 bytes, or 8,388,608 bits, which

2376-407: A page to be printed. (In certain cases, this might be the only way to recover one's data in the event of a system crash that occurred while printing.) The Form Feed button would print whatever was remaining in memory and prepare the printer to accept any new data as the start of a new page. For at least some LaserJet models, notably the LaserJet 4[M][Plus], the printer must be switched off-line before

2475-462: A page, to the business and home markets. No other commonly available printer during this era could also offer this combination of features. A laser beam projects an image of the page to be printed onto an electrically charged, photoconductive , rotating, cylindrical drum. Photoconductivity conducts charged electrons away from the areas exposed to laser light. Powdered ink ( toner ) particles are then electrostatically attracted to remaining areas of

2574-447: A printer before the late 1990s, might not understand these indicators, or might think they are conflicting or ambiguous. It may not be intuitive to new users that a printer that is ready but offline does not print, and while being able to take the printer off line (effectively disconnecting it from the computer) without shutting it down can be very useful, this distinction may appear as an extra complication to users who want to casually use

2673-414: A slower page-printing speed because of the longer paper path. Formerly only available on high-end printers, duplexers are now common on mid-range office printers, though not all printers can accommodate a duplexing unit. In a commercial environment such as an office, it is becoming increasingly common for businesses to use external software that increases the performance and efficiency of laser printers in

2772-591: A standard 72-pin SIMM of appropriate capacity to support HP PD by soldering wires to pads, a simple task. HP printers of this type specify that RAM not faster than 70ns be used; this is probably due to a limitation of the PD decoding, and faster RAM can actually be used so long as the PD encoding indicates a speed of 70ns or slower. All printers will work with FPM (Fast Page Mode) memory; many, but not all, will work with EDO (Extended Data Out) memory. Some even older models, such as

2871-403: A two-step process whereby the color laser printers use colored toner (dry ink), typically cyan , magenta , yellow , and black ( CMYK ); however, newer printers designed to print on dark T-shirts utilize a special white toner allowing them to make transfers for dark garments or dark business products. The CMYK color printing process allows for millions of colors to be faithfully represented by

2970-523: Is a form of image processing technology used to manipulate dot characteristics popular among laser printer and inkjet printer manufacturers. Closely related RET techniques are also used in VLSI photolithography manufacturing technology, in particular in relation to 90 nanometre technology. Resolution refers to the sharpness of image detail, smoothness of curved lines, and the faithful reproduction of an image. In both cases, RET uses pre-compensation of

3069-434: Is coated with selenium , or more recently, with an organic photoconductor made of N-vinylcarbazole , an organic monomer . There are typically seven steps involved in the process, detailed in the sections below. The document to be printed is encoded in a page description language such as PostScript, Printer Command Language (PCL), or Open XML Paper Specification (OpenXPS). The raster image processor (RIP) converts

HP LaserJet - Misplaced Pages Continue

3168-455: Is just large enough to hold the entire page at 300 dpi, leaving about 100 kilobytes to spare for use by the raster image processor. In a color printer, each of the four CMYK toner layers is stored as a separate bitmap, and all four layers are typically preprocessed before printing begins, so a minimum of 4 megabytes is needed for a full-color letter-size or A4-size page at 300 dpi. During the 1980s, memory chips were still very expensive, which

3267-741: Is limited by their resolution (typically 600–1200 dpi) and their use of just four color toners. They often have trouble printing large areas of the same or subtle gradations of color. Inkjet printers designed for printing photos can produce much higher quality color images. An in-depth comparison of inkjet and laser printers suggest that laser printers are the ideal choice for a high quality, volume printer, while inkjet printers tend to focus on large-format printers and household units. Laser printers offer more precise edging and in-depth monochromatic color. In addition, color laser printers are much faster than inkjet printers, although being generally larger and bulkier. Many modern color laser printers mark printouts by

3366-461: Is more roller contact time for the toner to melt, and the fuser can operate at a lower temperature. Smaller, inexpensive laser printers typically print slowly, due to this energy-saving design, compared to large high-speed printers where paper moves more rapidly through a high-temperature fuser with very short contact time. As the drum completes a revolution, it is exposed to an electrically neutral soft plastic blade that cleans any remaining toner from

3465-408: Is suspended in the center of the hollow tube, and its infrared energy uniformly heats the roller from the inside. For proper bonding of the toner, the fuser roller must be uniformly hot. Some printers use a very thin flexible metal foil roller, so there is less thermal mass to be heated and the fuser can more quickly reach operating temperature . If paper moves through the fuser more slowly, there

3564-440: Is then rolled under the photoreceptor drum, which has been coated with a pattern of toner particles in the exact places where the laser struck it moments before. The toner particles have a very weak attraction to both the drum and the paper, but the bond to the drum is weaker and the particles transfer once again, this time from the drum's surface to the paper's surface. Some machines also use a positively charged "transfer roller" on

3663-437: Is too high, the toner will not fuse well to the paper and may flake off after printing. If the fuser is too hot, the plastic component of the toner may smear, causing the printed text to look like it is wet or smudged, or may cause the melted toner to soak through the paper to the backside. Different manufacturers claim that their toners are specifically developed for their printers and that other toner formulations may not match

3762-502: Is why entry-level laser printers in that era always came with four-digit suggested retail prices in US dollars. The primitive microprocessors in early personal computers were so underpowered and insufficient for graphics work that attached laser printers usually had more onboard processing power. Memory prices later decreased significantly, while rapid improvements in the performance of PCs and peripheral cables (most importantly, SCSI ) enabled

3861-694: The PostScript language, as developed by Adobe Systems . The use of a less-ambitious and simpler Page description language allowed HP to deliver its LaserJet to the market about a year before Apple's CX based product, and for $ 1000 less. The sharing of an identical Canon engine in two competing products continued with the LaserJet II/III and the Apple LaserWriter II, which both used the Canon LBP-SX print engine. HP introduced

3960-525: The Windows 95 era and many of the original manual control buttons like Form Feed were no longer necessary, because the Windows 95 print-spooler subsystem offered even simple Windows applications a much greater control over the printer than was available to DOS applications, which had to each independently rebuild and re-engineer basic printer management systems from scratch. This new Windows-oriented interface

4059-526: The photocopier market. In 1969, Gary Starkweather , who worked in Xerox's product development department, had the idea of using a laser beam to "draw" an image of what was to be copied directly onto the copier drum. After transferring to the recently formed Palo Alto Research Center (Xerox PARC) in 1971, Starkweather adapted a Xerox 7000 copier to make SLOT (Scanned Laser Output Terminal). In 1972, Starkweather worked with Butler Lampson and Ronald Rider to add

HP LaserJet - Misplaced Pages Continue

4158-683: The "World's Most Secure Printers". HP offers a standard one-year warranty on all of its LaserJet printers. Owners of its products can contact HP directly or any of its Authorized Service Providers to fulfill warranty service. After the first year an extended warranty can be purchased to continue coverage. As of 2017 the models that are still eligible for on-site warranty service are the following: M402, M506, M604, M605, M606, M607, M608, M609, M712, M806, M426, M521, M525, M527, M630, M631, M632, M633, M725, M830, M452, M451, M551, CP4025, M651, M652, M653, CP5225, M750, M855, M476, M477, M570, M575, M577, M680, M681, M682, M775, M880. After 7 years has passed since

4257-519: The 3Si (IIISi) and 4Si, which had used the Canon NX engine. The 5Si, based on the Canon WX engine, could thus provide 11"x17" printing at an unprecedented 24 pages per minute and at 600 dpi with resolution enhancement. An internal duplexer enabled full-speed double-sided printing. Automatic personality switching (between PCL and PostScript), a feature that first appeared on the 4SiMX, was standard on

4356-722: The 4 Plus/4M Plus) memory modules of 4, 8, 16 and 32 MB were available. In November 2011, researchers at Columbia University announced the discovery of widespread vulnerabilities in LaserJet printers that allowed malicious firmware to be uploaded to the printers remotely. Using weaknesses in the printers' Web-based control interface, attackers could traverse the directory tree of an unpatched computer's data storage, and then locate cached copies of otherwise restricted information, moments before or even after it has been printed. This information can then be forwarded to hackers for accumulation to facilitate harmful actions. The malicious firmware could also be crafted to exfiltrate printout data over

4455-539: The 5Si series was succeeded by the 8000, and later by the 8100 and 8150. The 8000 brought 1200x1200-dpi resolution, which was continued in the 8100 and 8150. The 8100 and 8150 brought faster printing (32 pages per minute), but this speed was only realized for single-sided (simplex) printing; double-sided printing remained at 24 pages per minute. These models, which used the Canon WX engine, provided durability and good maintainability. In December 2000 HP shipped its 50-millionth LaserJet printer. In September 2001 HP entered

4554-555: The 5SiMX. The 5Si series were true workhorses, but initial production models were somewhat hobbled by a vulnerability to slightly low voltage (i.e. crashing if mains voltage was less than 120 Volts) as well as a weak clutch in Tray 3 (thus resulting in paper jamming for Tray 3 as well as the optional 2,000-sheet Tray 4), and also a weak solenoid in the manual feed tray (Tray 1). These paper-handling issues were easily dealt with, and many 5Si LaserJets remain in service today. The HP 5Si Mopier,

4653-755: The 9000 series, which produced 50 pages per minute and used an internal duplexer. Meanwhile, the 4100 was replaced by the 4200 (later 4250) and 4300 (later 4350), which brought speeds of up to 55 pages per minute. In 2003 HP shipped its 75-millionth LaserJet printer. In November 2003, HP entered the $ 24-billion copier market with the LaserJet 9055/9065/9085 MFPs(multifunction printers), a copier-based line of high-volume multifunction printers. In 2006, total LaserJet sales had reached 100 million. As of 2007 HP has several lines of monochrome and color printers and multifunction products (copy, scan, and/or fax included) that range from 20 to 55 ppm and range in price from $ 149 to several thousand dollars. The 1992 LaserJet 4L marked

4752-512: The Form Feed button will work. Most users of dot-matrix printers in the 1980s probably found the Online and Form Feed functions obvious, as most dot-matrix printers had these buttons and they worked similarly. The indicator on the Form Feed button illuminates when there is received data in the printer's buffer; this makes it much easier to predict what will happen if the printer is put online and

4851-706: The Japanese company Canon . Due to a tight turnaround schedule on the first LaserJet, HP elected to use the controller already developed by Canon for the CX engine in the first LaserJet. In spring of 1989 The New York Times said that HP "dominates" the PC laser printer market. The first LaserJet and the first Apple LaserWriter used the same print engine, the Canon CX engine. HP chose to use their in-house developed Printer Command Language (PCL) as opposed to Apple, which adopted

4950-502: The LCD displays of earlier models by using a 16-character alphanumeric dot-matrix vacuum fluorescent display. To this day, professional-grade LaserJets retain more comprehensive displays. Before the 4L, the control panel typically had buttons with names like Online, Menu, Shift, Continue, Reset, +, -, and Form Feed. It also included status indicators like Online and Ready. Users without a technical background, especially those who had not used

5049-541: The LaserJet 4/5 series if the user had them previously. In 1999, HP released the LaserJet 4050 series, which was identical to the HP 4000 but with a faster formatter and an easily accessible paper registration area (where the paper is stopped, registered, and then advanced for printing; a flip-up cover here made clearing of this component easier.) The 4000 series, as well as the 4050 and the 4100, used partly external duplexers. The world's first mass market all-in-one laser device ,

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5148-471: The LaserJet 4101 MFP, debuted in April 1998. Users could print, fax, copy, and scan with a single appliance. In July 1998 HP shipped its 30-millionth LaserJet printer. In February 1999, HP introduced the LaserJet 2100 printer series – the world's first personal laser printers in their class to offer high-quality 1200x1200-dpi resolution without significant performance loss. In the network laser-printer market,

5247-407: The LaserJet 600 series now include a full color LCD display. Two directional arrow buttons and a Ok button replace the multiple menu navigation buttons of the 4000 series. A numeric keypad and other specialized buttons are also included for job storage, copy, and fax usage on models with those features. The model numbers do not necessarily have anything to do with the order of product development or

5346-514: The LaserJet II, IID, III, IIID, and 4/4M (i.e. not 4 Plus/4M Plus), used proprietary memory expansion boards. For example, the II and IID models used a roughly 4" square memory expansion board populated with DIP DRAM chips and a two-row header connector (with pins on standard 0.1" centers), while the 4/4M used 72 pin parity memory (and would fail to POST with non-parity memory). For the 4/4M (and

5445-413: The backside of the paper to help pull the negatively charged toner from the photoreceptor drum to the paper. The paper passes through rollers in the fuser assembly, where temperatures up to 427 °C (801 °F) and pressure are used to permanently bond the toner to the paper. One roller is usually a hollow tube (heat roller) and the other is a rubber-backed roller (pressure roller). A radiant heat lamp

5544-410: The blade allows too much toner to remain on the developer roll, the toner particles might come loose as the roll turns, precipitate onto the paper below, and become bonded to the paper during the fusing process. This will result in a general darkening of the printed page in broad vertical stripes with very soft edges. If the fuser roller does not reach a high enough temperature or if the ambient humidity

5643-458: The businesses and institutions at which it was targeted. Later, in 1984, the first laser printer intended for mass-market sales, the HP LaserJet , was released; it used the Canon CX engine, controlled by HP software. The LaserJet was quickly followed by printers from Brother Industries , IBM , and others. First-generation machines had large photosensitive drums, of circumference greater than

5742-482: The computer screen. (TrueType fonts could print on an original LaserJet Plus or later, but they would be printed as graphics, making the printing slow and restricted to a limited page area or reduced resolution.) Some competitors also utilized the Canon EX engine, including Apple (LaserWriter Pro 600 and 630), Digital Equipment Corporation (DEClaser 5100), and Canon. By installing an HP JetDirect print server card,

5841-548: The control panel was easier and more intuitive: menus could be navigated with the Menu button. Then, items within the menu selected with the Item button. The Value button – which had - (decrease) and + (increase) indications – could be used to select a specific setting or value. The Select button was used to select or confirm a particular choice. The display was adapted to a blue-backlit two-line LCD display. Newer models such as

5940-449: The development of low-end laser printers which offload rasterization to the sending PC. For such printers, the operating system's print spooler renders the raw bitmap of each page into the PC's system memory at the target resolution, then sends that bitmap directly to the laser (at the expense of slowing down all other programs on the sending PC). The appearance of so-called "dumb" or "host-based" laser printers from NEC made it possible for

6039-415: The drum that have not been laser-beamed. The drum then transfers the image onto paper which is passed through the machine by direct contact. Finally, the paper is passed onto a finisher, which uses heat to instantly fuse the toner that represents the image onto the paper. The laser is typically an aluminium gallium arsenide (AlGaAs) semiconductor laser ), which emits red or infrared light. The drum

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6138-422: The drum to pick up excessive toner on the next revolution from the developer roll and causing a repeated but fainter image from the previous revolution to appear down the page. If the toner doctor blade does not ensure that a smooth, even layer of toner is applied to the developer roll, the resulting printout may have white streaks from this in places where the blade has scraped off too much toner. Alternatively, if

6237-419: The drum which were struck by the laser, however, momentarily have no charge, and the toner being pressed against the drum by the toner-coated developer roll in the next step moves from the roll's rubber surface to the charged portions of the surface of the drum. Some non-laser printers ( LED printers ) use an array of light-emitting diodes spanning the width of the page to generate an image, rather than using

6336-406: The drum, causing those areas to appear as white vertical streaks. If the neutral wiper blade fails to remove residual toner from the drum's surface, that toner may circulate on the drum a second time, causing smears on the printed page with each revolution. If the charge roller becomes damaged or does not have enough power, it may fail to adequately negatively charge the surface of the drum, allowing

6435-478: The first "personal" version of the LaserJet printer series, the LaserJet IIP. Priced at US$ 1,495 by HP, and half the size and price of its predecessor, the LaserJet II, it offered 300-dpi output and 4 ppm printing with PCL 4 enhancements such as support for compressed bitmapped fonts and raster images. It was also the first no ozone print engine. Retailers predicted a street price of $ 1000 or less, making it

6534-427: The first LaserJet only had 128 kilobytes of memory, and a portion of that was reserved for use by the controller. The LaserJet printer had high print quality, could print horizontally or vertically and produce graphics. It was ideal for printing memos, letters, and spreadsheets. It was quiet compared to other contemporary printers, hence people could use the telephone while sitting near the LaserJet. The first LaserJet

6633-525: The first laser printer for IBM PC compatible personal computers in May 1984 at the Computer Dealers' Exhibition ( COMDEX ). It was a 300- dpi , 8 ppm printer that sold for $ 3,495 with the price reduced to $ 2,995 in September 1985. It used an 8 MHz Motorola 68000 processor and could print in a variety of character fonts. It was controlled using PCL3 . Due to the high cost of memory,

6732-439: The four colors. Color printing adds complexity to the printing process because very slight misalignments known as registration errors can occur between printing each color, causing unintended color fringing, blurring, or light/dark streaking along the edges of colored regions. To permit a high registration accuracy, some color laser printers use a large rotating belt called a "transfer belt". The transfer belt passes in front of all

6831-407: The late 1990s, monochrome laser printers had become inexpensive enough for home-office use, having displaced other printing technologies, although color inkjet printers (see below) still had advantages in photo quality reproduction. As of 2016 , low-end monochrome laser printers can sell for less than $ 75, and while these printers tend to lack onboard processing and rely on the host computer to generate

6930-480: The loaded paper's length. Once faster-recovery coatings were developed, the drums could touch the paper multiple times in a pass, and therefore be smaller in diameter. A year later, Apple introduced the LaserWriter (also based on the Canon CX engine), but used the newly released PostScript page-description language (up until this point, each manufacturer used its own proprietary page-description language, making

7029-678: The loading of fonts . The Xerox 9700 excelled at printing high-value documents on cut-sheet paper with varying content (e.g. insurance policies). Inspired by the Xerox 9700's commercial success, Japanese camera and optics company Canon developed in 1979 the Canon LBP-10, a low-cost desktop laser printer. Canon then began work on a much-improved print engine, the Canon CX, resulting in the LBP-CX printer. Having no experience in selling to computer users, Canon sought partnerships with three Silicon Valley companies: Diablo Data Systems (who rejected

7128-405: The low-end laser printer market with the introduction of the LaserJet 1000: the first sub-$ 250 LaserJet and the lowest-priced monochrome (black and white) LaserJet printer to date. It offered 10 ppm, an HP Instant-on fuser, 600 dpi with HP REt boosting output effectively to 1200 dpi, a 2.5-cent cost per page, and a 7,000-page monthly duty cycle. In 2002, the 8150 was discontinued and was replaced by

7227-555: The manufacturer to identify the place of purchase, and sometimes the buyer. Digital-rights advocacy groups such as the Electronic Frontier Foundation are concerned about this erosion of the privacy and anonymity of those who print. In particular, the tracking dots were implicated as a tool that directly lead to the arrest and conviction of whistleblower Reality Winner . Resolution enhancement technology Resolution enhancement technology ( RET )

7326-456: The network, to attack other computers on the network, or even to cause a printer to intentionally overheat. Security update patches were strongly urged by HP. As of late 2011, Computerworld stated that "Millions of HP LaserJet printers" still had "a security weakness that could allow attackers to take control of" their hardware. In September 2015, HP added new features to its printers to address security vulnerabilities, releasing what they called

7425-584: The offer), Hewlett-Packard (HP), and Apple Computer . In 1981, the first small personal computer designed for office use, the Xerox Star 8010, reached market. The system used a desktop metaphor that was unsurpassed in commercial sales, until the Apple Macintosh . Although it was innovative, the Star workstation was a prohibitively expensive ( US$ 17,000 ) system, affordable only to a fraction of

7524-558: The original specifications in terms of either tendency to accept a negative charge, to move to the discharged areas of the photoreceptor drum from the developer roll, to fuse appropriately to the paper, or to come off the drum cleanly in each revolution. As with most electronic devices, the cost of laser printers has decreased significantly over the years. In 1984, the HP LaserJet sold for $ 3500, had trouble with even small, low-resolution graphics, and weighed 32 kg (71 lb). By

7623-411: The page description into a bitmap which is stored in the printer's raster memory. Each horizontal strip of dots across the page is known as a raster line or scan line . Laser printing differs from other printing technologies in that each page is always rendered in a single continuous process without any pausing in the middle, while other technologies like inkjet can pause every few lines. To avoid

7722-416: The paper passes through the fuser assembly, the particles of toner melt. The paper may or may not be oppositely charged. The fuser can be an infrared oven, a heated pressure roller, or (on some very fast, expensive printers) a xenon flash lamp . The warmup process that a laser printer goes through when power is initially applied to the printer consists mainly of heating the fuser element. The mechanism inside

7821-402: The photoreceptor drum and deposits it into a waste reservoir. A charge roller then re-establishes a uniform negative charge on the surface of the now-clean drum, readying it to be struck again by the laser. Once the raster image generation is complete, all steps of the printing process can occur one after the other in rapid succession. This permits the use of a very small and compact unit, where

7920-419: The photoreceptor is charged, rotates a few degrees and is scanned, rotates a few more degrees, and is developed, and so forth. The entire process can be completed before the drum completes one revolution. Different printers implement these steps in distinct ways. LED printers use a linear array of light-emitting diodes to "write" the light on the drum. The toner is based on either wax or plastic, so that when

8019-415: The printer merely as an information appliance. When a Windows PC controls a LaserJet, the "Form Feed" button seldom does anything when pressed. It has a small indicator light, and was usually used with very simple DOS programs that did not eject the last page after sending data to the printer, though it could also be useful to print the data in the printer's memory if a program failed in the middle of sending

8118-434: The printer will power up and print a test page including total number of pages printed. A short press would provide a form feed or tell the printer to resume from a paper jam or out-of-paper condition. The actual application of the button was supposed to be far more intuitive than any possible written description – basically, the button tells the printer "whatever you're doing now, do the next most logical thing"). This interface

8217-400: The printer, it is necessary to make the computer stop sending data for the print job to the printer, if it has not already finished sending that job, through the computer's software. Otherwise, when the printer is put back online, it will start receiving the job from somewhere in the middle, which will likely cause the same runaway problem to recur.) But by 1999 personal computers had embraced

8316-492: The retail cost of low-end 300-dpi laser printers to decrease to as low as US$ 700 by early 1994 and US$ 600 by early 1995. In September 1997, HP introduced the host-based LaserJet 6L, which could print 600 dpi text at up to six pages per minute for only US$ 400. 1200 dpi printers have been widely available in the home market since 2008. 2400 dpi electrophotographic printing plate makers, essentially laser printers that print on plastic sheets, are also available. In older printers,

8415-490: The supporting software complex and expensive). PostScript allowed the use of text, fonts, graphics, images, and color largely independent of the printer's brand or resolution. PageMaker , developed by Aldus for the Macintosh and LaserWriter, was also released in 1985 and the combination became very popular for desktop publishing . Laser printers brought exceptionally fast and high-quality text printing in multiple fonts on

8514-413: The sweep, and the angle of sweep is canted very slightly to compensate for this motion. The stream of rasterized data held in the printer's memory rapidly turns the laser on and off as it sweeps. The laser beam neutralizes (or reverses) the charge on the surface of the drum, leaving a static electric negative image on the drum's surface which will repel the negatively charged toner particles. The areas on

8613-486: The toner cartridges and each of the toner layers are precisely applied to the belt. The combined layers are then applied to the paper in a uniform single step. Color printers usually have a higher cost per page than monochrome printers, even if printing monochrome-only pages. Liquid electrophotography (LEP) is a similar process used in HP Indigo presses that uses electrostatically charged ink instead of toner, and using

8712-475: The transition between a control panel evolved for an informed operator and one evolved for a casual user. The 4L's predecessor, the IIIP, had an array of buttons and a cryptic numerical LCD. The 4L shipped with 4 LEDs, each with an icon to indicate a different condition, and a single pushbutton whose purpose varied depending on context (i.e. Hold down during printing, the printer will cancel the job. Hold down when off,

8811-933: The type of print-engine technology. For example, the LaserJet 1018 printer has newer, smaller, and more energy-efficient technology than the LaserJet 4000. The 1018 also features USB while the older 4000 does not. (Source: HP.com ) Printers with factory-installed options have different model-numbers to denote the different options included and to differentiate a specific model from others in its series. These suffixes include: Many older LaserJets and other HP printers (including LaserJet 4+, 4MV, 4MP, 4P, 5, 5M, 5MP, 5N, 5P, 5se, 5Si MOPIER, 5Si, 5Si NX, 6MP, 6P, 6Pse, 6Pxi, C3100A; DesignJet 330, 350C, 700, 750C, 750C Plus; DeskJet: 1600C, 1600CM, 1600CN; and PaintJet XL300) used proprietary 72-pin HP SIMMs for memory expansion. These are essentially industry-standard 72-bit SIMMs with non-standard Presence Detect (PD) connections. One can often adapt

8910-530: The unique imaging process. Manufacturers use a similar business model for both low-cost color laser printers and inkjet printers : the printers are sold cheaply while replacement toners and inks are relatively expensive. A color laser printer's average running cost per page is usually slightly less, even though both the laser printer and laser toner cartridge have higher upfront prices, as laser toner cartridges print many more sheets relative to their cost than inkjet cartridges. The print quality of color lasers

9009-480: The workplace. The software can be used to set rules dictating how employees interact with printers, such as setting limits on how many pages can be printed per day, limiting usage of color ink, and flagging jobs that appear to be wasteful. Color laser printers use colored toner (dry ink), typically cyan , magenta , yellow , and black ( CMYK ). While monochrome printers only use one laser scanner assembly, color printers often have two or more, often one for each of

9108-560: The world's first sub-$ 1,000 laser printer. The LaserJet IIP (and its very similar successor, the IIIP) were reliable. Aftermarket replacement scanner assemblies remain available today. In March 1990 HP introduced the LaserJet III, priced at US$ 2,395, with two new features: Resolution Enhancement technology (REt) , which dramatically increased print quality, and HP PCL 5. Thanks to PCL 5, text scaling became easy, and thus customers were no longer restricted to 10- and 12-point type sizes. This had

9207-409: Was HP's first printer to offer onboard Adobe PostScript emulation as opposed to the font-cartridge solution offered on earlier models. In October 1992, HP introduced the LaserJet 4 featuring a Canon EX engine with native 600-dpi output and Microfine toner for US$ 2,199. This model also introduced TrueType fonts to LaserJets which ensured that the printer fonts exactly matched the fonts displayed on

9306-657: Was a high-speed replacement for text-only daisy wheel impact printers and the noisy dot matrix printers . By using control codes it was possible to change the printed text style using font patterns stored in permanent ROM in the printer. Although unsupported by HP, because the Laserjet used the same basic PCL language (PCL Level III) spoken by HP's other printers it was possible to use the Laserjet on HP 3000 multiuser systems. The LaserJet Plus followed in September 1985, priced at US$ 3,995. It introduced "soft fonts", treatments like bold and italic and other features including

9405-538: Was highly intuitive and obvious to the casual user, who needed little familiarization with the printer to use it effectively. Raw, unformatted, text-only support still exists, but the professional LaserJet printers keep it hidden away. Most professional LaserJet printers include a PCL menu where the number of copies, the font style, portrait or landscape printing, and the number of lines-per-page can be defined. These settings are ignored by graphical PCL/Postscript print drivers, and are only used for those rare situations where

9504-415: Was introduced with the LaserJet 4L in the spring of 1993. It included a new low cost print engine. It sold for $ 1,229. The Color LaserJet 5 and 5M were introduced in March 1996, with 1200 dpi resolution. The LaserJet 6P and 6MP were introduced October 1996. They included infrared technology, for wireless printing. In November 1996 HP introduced the network-ready LaserJet 5Si, a major revision and upgrade to

9603-477: Was invented at Xerox PARC in the 1970s. Laser printers were introduced for the office and then home markets in subsequent years by IBM , Canon , Xerox, Apple , Hewlett-Packard and many others. Over the decades, quality and speed have increased as prices have decreased, and the once cutting-edge printing devices are now ubiquitous. In the 1960s, the Xerox Corporation held a dominant position in

9702-421: Was supposed to be easier for new and casual users to understand and use, but it was also much less powerful, as in any case there is only one thing a user can make the printer do. Until the user becomes familiar with the printer's behavior, they have to guess what that one thing is, or else consult the manual. A 4L's four status LEDs will also light in unusual patterns to indicate service requirements; for example,

9801-453: Was used for high-volume printing on continuous stationery , and achieved speeds of 215 pages per minute (ppm), at a resolution of 240 dots per inch (dpi). Over 8,000 of these printers were sold. Soon after, in 1977, the Xerox 9700 was brought to market. Unlike the IBM 3800, the Xerox 9700 was not targeted to replace any particular existing printers; however, it did have limited support for

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