Misplaced Pages

#854145

82-655: The LaserWriter is a laser printer with built-in PostScript interpreter sold by Apple, Inc. from 1985 to 1988. It was one of the first laser printers available to the mass market. In combination with WYSIWYG publishing software like PageMaker that operated on top of the graphical user interface of Macintosh computers, the LaserWriter was a key component at the beginning of the desktop publishing revolution. Laser printing traces its history to efforts by Gary Starkweather at Xerox in 1969, which resulted in

164-574: 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

246-568: A Ricoh engine for $ 12,800 in 1983. Sales of the non-networked product were unsurprisingly poor. In 1983, Canon introduced the LBP-CX, a desktop laser printer engine using a laser diode and featuring an output resolution of 300 dpi. In 1984, HP released the first commercially available system based on the LBP-CX, the HP LaserJet . Steve Jobs of Apple Computer had seen the LBP-CX while negotiating for supplies of 3.5" floppy disk drives for

328-412: 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

410-481: 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

492-637: 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

574-536: A "reference model" (but with customization for the Linotronic's different video interface, plus the necessary implementation of "banding" and a hard drive frame buffer and font storage mechanism). Indeed, the PostScript language itself was concurrently enhanced and extended to support these high-resolution "banding" devices (as contrasted to the lower resolution "framing" devices, such as the LaserWriter, in which

656-433: 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

738-570: A commercial system called the Xerox 9700 . IBM followed this with the IBM 3800 system in 1976. Both machines were large, room-filling devices handling the combined output of many users. During the mid-1970s, Canon started working on similar machines, and partnered with Hewlett-Packard to produce 1980's HP 2680, which filled only part of a room. Other copier companies also started development of similar systems. HP introduced their first desktop model with

820-420: 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

902-429: 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

SECTION 10

#1732765616855

984-405: 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

1066-428: 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

1148-414: 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

1230-713: A market in which the Mac is still important. The LaserWriter was the first major printer designed by Apple to use the new Snow White design language created by Frog Design . It also continued a departure from the beige color that characterized the Apple and Macintosh products to that time by using the same brighter, creamy off-white color first introduced with the Apple IIc and Apple Scribe Printer 8 months earlier. In that regard it and its successors stood out among all of Apple's Macintosh product offerings until 1987, when Apple adopted

1312-538: 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

1394-445: 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

1476-513: 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

1558-462: 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

1640-414: 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

1722-411: A suitable interpreter and then sent to a software rasterizer program, all inside the printer. To support this, the LaserWriter featured a Motorola 68000 CPU running at 12  MHz , 512 KB of workspace RAM , and a 1 MB frame buffer. At introduction, the LaserWriter had the most processing power in Apple's product line—more than the 8 MHz Macintosh. As a result, the LaserWriter

SECTION 20

#1732765616855

1804-403: 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

1886-544: A unifying warm gray color they called Platinum across its entire product line, which was to last for over a decade. The LaserWriter was also the first peripheral to use the LocalTalk connector and Apple's unified round AppleTalk Connector Family, which allowed any variety of mechanical networking systems to be plugged into the ports on the computers or printers. A common solution was the 3rd party PhoneNET which used conventional telephone cables for networking. Apple's RIP

1968-460: Is a page description language (PDL) developed by Hewlett-Packard as a printer protocol and has become a de facto industry standard . Originally developed for early inkjet printers in 1984, PCL has been released in varying levels for thermal , matrix , and page printers. HP-GL/2 and PJL are supported by later versions of PCL. PCL is occasionally and incorrectly said to be an abbreviation for Printer Control Language which actually

2050-519: Is another term for page description language . PCL levels 1 through 5e/5c are command-based languages using control sequences that are processed and interpreted in the order they are received. At a consumer level, PCL data streams are generated by a print driver. PCL output can also be easily generated by custom applications. HP introduced PCL 6 around 1995 with the HP LaserJet 4000 series printers. It consists of: PCL 6 "Enhanced" architecture

2132-434: 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

2214-455: 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

2296-741: 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

2378-461: 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

2460-408: 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

2542-440: 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

LaserWriter - Misplaced Pages Continue

2624-437: 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

2706-502: 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

2788-414: The HP LaserJet and other non-Postscript printers. Paired with the program Aldus PageMaker , the LaserWriter gave the layout editor an exact replica of the printed page. The LaserWriter offered a generally faithful proofing tool for preparing documents for quantity publication, and could print smaller quantities directly. The Mac platform quickly gained the favor of the emerging desktop-publishing industry,

2870-425: The "frame buffer", for the lowest resolution devices, 300 dpi), as more than 300 dpi of course required more RAM, and some LaserWriters were able to change between 300 dpi and 600 dpi, depending upon how much RAM was installed. 600 dpi, for example, required 6 MB of RAM, but 8 MB of RAM was more commonly found. At this point, Apple's LaserWriters were employing generic non-parity RAM, whereas HP's LaserJets, especially

2952-656: The 1960s, the Xerox Corporation held a dominant position in 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

3034-537: The HP model. However, the LaserWriter featured AppleTalk support that allowed the printer to be shared among as many as sixteen Macs, meaning that its per-user price could fall to under $ 450, far less expensive than HP's less-advanced model. The combination of the LaserWriter, PostScript, PageMaker and the Mac's GUI and built-in AppleTalk networking would ultimately transform the landscape of computer desktop publishing. At

3116-547: The LaserWriter II was designed to allow for complete replacement of the computer circuit board that operates the printer. Across all the different models, the print engine was the same. Three years later in 1991, two updated versions of the LaserWriter II were produced. To deliver higher performance, Apple eventually switched from the 68000 series to the Am29000 series of processors to drive later models, starting with

3198-465: The LaserWriter to the Mac over an RS-422 serial port. At 230.4 kbit / s LocalTalk was slower than the Centronics PC parallel interface, but allowed several computers to share a single LaserWriter. PostScript enabled the LaserWriter to print complex pages containing high-resolution bitmap graphics , outline fonts , and vector illustrations. The LaserWriter could print more complex layouts than

3280-533: The PCL 5 backward compatibility. PCL 6 Enhanced is primarily generated by the printer drivers under Windows and CUPS . Due to its structure and compression methodology, custom applications rarely use it directly. PCL 6 Enhanced is a stack-based, object-oriented protocol, similar to PostScript . However, it is restricted to binary encoding as opposed to PostScript, which can be sent either as binary code or as plain text. The plain-text commands and code examples shown in

3362-540: The PCL programming documentation are meant to be compiled with a utility like HP's JetASM before being sent to a printer. PCL 6 Enhanced is designed to match the drawing model of Windows GDI . In this way, the Windows printer driver simply passes through GDI commands with very little modification, leading to faster return-to-application times. Microsoft has extended this concept with its next-generation XPS format, and printer implementations of XPS are being developed. This

LaserWriter - Misplaced Pages Continue

3444-507: The Personal LaserWriter NTR in 1992. Laser printing The laser printer 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

3526-413: 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

3608-410: 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

3690-455: 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

3772-497: 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

3854-415: 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

3936-422: 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

4018-419: 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

4100-406: 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

4182-517: The entire "frame" could be contained within the available RAM ). In most cases, such RAM was fixed in size and was soldered to the logic board. In late PostScript Level 1, and in early PostScript Level 2, the RAM size was made variable and was generally extensible, through plug-in DIMMs, beyond the 2.0 to 2.5 MB minimum (0.5 to 1.0 MB for instructions, depending upon PostScript version, and 1.5 MB minimum for

SECTION 50

#1732765616855

4264-439: 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

4346-407: 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

4428-462: The level of detail and control over the page layout. HP's own LaserJet was driven by a simple page description language , known as Printer Command Language , or PCL. The version for the LaserJet, PCL4, was adapted from earlier inkjet printers with the addition of downloadable bitmapped fonts. It lacked the power and flexibility of PostScript until several upgrades provided some level of parity. It

4510-480: 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

4592-625: 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

4674-565: 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 . Printer Command Language Printer Command Language , more commonly referred to as PCL ,

4756-501: The new printer. Arranging his own funding through a venture capital firm, Brainerd formed Aldus and began development of what would become PageMaker . The venture capital coined the term "desktop publishing" during this time. The LaserWriter was announced at Apple's annual shareholder meeting on January 23, 1985, the same day Aldus announced PageMaker. Shipments began in March 1985 at the retail price of US$ 6,995, significantly more than

4838-584: 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

4920-596: The ones which offered a plug-in PostScript interpreter card, required special parity-type PS/2 RAM modules with a "presence detect" function according to IBM specs. Building on the success of the original LaserWriter, Apple developed many further models. Later LaserWriters offered faster printing, higher resolutions , Ethernet connectivity, and eventually color output in the Color LaserWriter . To compete, many other laser printer manufacturers licensed Adobe PostScript for inclusion into their own models. Eventually

5002-498: 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

SECTION 60

#1732765616855

5084-411: 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

5166-416: 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

5248-402: 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

5330-419: 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

5412-492: 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,

5494-407: The same time-frame as Apple's LaserWriter, Adobe was licensing the very same version of PostScript to Apple's potential competitors (Apple's PostScript licensing terms were non-exclusive); however, all non-Apple licensees of PostScript generally employed one of Adobe's PostScript "reference models" (Atlas, Redstone, etc.) and even Linotype 's first image setter which featured PostScript employed such

5576-415: The standardization on Ethernet for connectivity and the ubiquity of PostScript undermined the unique position of Apple's printers: Macintosh computers functioned equally well with any Postscript printer. After the LaserWriter 8500, Apple discontinued the LaserWriter product line in 1997 when Steve Jobs returned to Apple. In 1988, to address the need for both an affordable printer and a professional printer,

5658-490: 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

5740-413: 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

5822-481: The time, Apple planned to release a suite of AppleTalk products as part of the Macintosh Office , with the LaserWriter being only the first component. While competing printers and their associated control languages offered some of the capabilities of PostScript, they were limited in their ability to reproduce free-form layouts (as a desktop publishing application might produce), use outline fonts , or offer

5904-486: 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

5986-530: 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

6068-416: The upcoming Apple Macintosh computer. Meanwhile, John Warnock had left Xerox to found Adobe Systems to commercialize PostScript and AppleTalk in a laser printer they intended to market. Jobs was aware of Warnock's efforts, and upon his return to California he began convincing Warnock to allow Apple to license PostScript for a new printer that Apple would sell. Negotiations between Apple and Adobe over

6150-554: The use of PostScript began in 1983 and an agreement was reached in December 1983, one month before Macintosh was announced. Jobs eventually arranged for Apple to buy $ 2.5 million in Adobe stock. At about the same time, Jonathan Seybold ( John W. Seybold 's son) introduced Paul Brainerd to Apple, where he learned of Apple's laser printer efforts and saw the potential for a new program using the Mac's GUI to produce PostScript output for

6232-481: The very same LBP-CX form factor, although the external packaging was, for marketing purposes, somewhat different. Since the cost of a LaserWriter was several times that of a dot-matrix impact printer , some means to share the printer with several Macs was desired. LANs were complex and expensive, so Apple developed its own networking scheme, LocalTalk . Based on the AppleTalk protocol stack , LocalTalk connected

6314-480: 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

6396-488: Was also one of Apple's most expensive offerings. For implementation purposes, the LaserWriter employed a small number of medium-scale-integration Monolithic Memories PALs , and no custom LSI , whereas the LaserJet employed a large number of small-scale-integration Texas Instruments 74-Series gates, and one custom LSI. The LaserWriter was, thereby, in the same form factor (for its RIP ), able to provide much greater function, and, indeed, much greater performance, all within

6478-446: Was altered to be more modular and to be more easily modified for future HP printers, that it prints complex graphics faster, that it reduces network traffic, and has higher quality. In early implementations, HP did not market PCL 6 well , thus causing some confusion in terminology. PCL XL was renamed to PCL 6 Enhanced, but many third-party products still use the older term. Some products may claim to be PCL 6 compliant, but may not include

6560-443: Was of its own design, and was implemented using few ICs, including PALs for most combinatorial logic; with the subsystem timing DRAM refreshing, and rasterization functions being implemented in very few medium-scale-integration PALs. Apple's competitors (i.e., QMS , NEC , and others) generally used a variation of one of Adobe's RIPs with their large quantity of small-scale-integration (i.e., Texas Instruments ' 7400 series) ICs. In

6642-400: Was some time before similar products became available on other platforms, by which time the Mac had ridden the desktop publishing market to success. The LaserWriter used the same Canon CX printing engine as the HP LaserJet, and as a consequence early LaserWriters and LaserJets shared the same toner cartridges and paper trays. PostScript is a complete programming language that has to be run in

6724-453: 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

#854145