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60-405: The perceived quality of dot matrix printers depends on the vertical and horizontal resolution and the ability of the printer to overlap adjacent dots. 9-pin and 24-pin are common; this specifies the number of pins in a specific vertically aligned space. With 24-pin printers, the horizontal movement can slightly overlap dots, producing visually superior output ( near letter-quality or NLQ), usually at

120-617: A serial interface (LA30-S); however, the serial LA30 required the use of fill characters during the carriage-return. In 1972, a receive-only variation named LA30A became available. The LA30 was followed in 1974 by the LA36, which achieved far greater commercial success, becoming for a time the standard dot matrix computer terminal. The LA36 used the same print head as the LA30 but could print on forms of any width up to 132 columns of mixed-case output on standard green bar fanfold paper . The carriage

180-446: A stepper motor , rotary encoder attached to one wheel, or a transparent plastic band with markings that is read by an optical sensor on the printer head (common on inkjets ). Because the printing involves mechanical pressure, dot matrix printers can create carbon copies and carbonless copies . Although nearly all inkjet , thermal , and laser printers also print closely spaced dots rather than continuous lines or characters, it

240-565: A conventional printer was replaced by a spinning, fluted cylinder. The print head was a simple hammer, with a vertical projecting edge, operated by an electromagnet. Where the vertical edge of the hammer intersected the horizontal flute of the cylinder, compressing the paper and ribbon between them, a single dot was marked on the paper. Characters were built up of multiple dots. Unlike the LA30 's 80-column, uppercase-only 5 x 7 dot matrix, DEC's product line grew. New models included: The DECwriter LA30

300-424: A horizontally moving print head. The print head can be thought of featuring a single vertical column of seven or more pins approximately the height of a character box. In reality, the pins are arranged in up to four vertically or/and horizontally slightly displaced columns in order to increase the dot density and print speed through interleaving without causing the pins to jam. Thereby, up to 48 pins can be used to form

360-504: A limited, 96 character set, gradually were able to produce output of comparable quality. Daisy wheel technology is now mostly defunct, though is still found in electronic typewriters. In 1889 Arthur Irving Jacobs patented a daisy wheel design that was used on the Victor index typewriter. A. H. Reiber of Teletype Corporation received in 1939 for a daisy wheel printer. In 1970 a team at Diablo Systems led by engineer Dr Andrew Gabor developed

420-629: A severe speed penalty. Because of the slow speed of NLQ printing, all NLQ printers have at least one "draft mode", in which the same fonts are used, but with only one pass of the print head per line. This produces lower-resolution printing, but at higher speed. Expensive NLQ printers had multiple fonts built-in, and some had a slot where a font cartridge could be inserted to add more fonts. Printer utility software could be used to print with multiple fonts on less-expensive printers. Not all of these utilities worked with all printers and applications, however. Daisywheel printer Daisy wheel printing

480-424: A single impact, without requiring fine rotation control of the platen roller. However it would require a specialised daisy wheel so printing of a letter and letterhead would require a two-step process with a manual wheel change in-between. As the development of this technique post-dated the widespread availability of 24-pin dot matrix printers and coincided with the arrival of affordable laser printers in offices, it

540-424: A standard feature to facilitate connections to modern computers without legacy ports. Near letter-quality printing Near letter-quality ( NLQ ) printing is a process where dot matrix printers produce high-quality text by using multiple passes to produce higher dot density. The tradeoff for the improved print quality is reduced printing speed. Software can also be used to produce this effect. The term

600-468: A time. The printer head is attached to a metal bar that ensures correct alignment, but horizontal positioning is controlled by a band that attaches to sprockets on two wheels at each side which is then driven with an electric motor. This band may be made of stainless steel, phosphor bronze or beryllium copper alloys, nylon or various synthetic materials with a twisted nylon core to prevent stretching. Actual position can be found out either by dead count using

660-463: A true letter-quality printer such as a daisy wheel or laser printer, print quality was greatly superior to a 9-pin printer. As manufacturing costs declined, 24-pin printers gradually replaced 9-pin printers. By the dawn of the 1990s, inkjet printers became more common as PC printers. Dot matrix printing uses a print head that moves back-and-forth, or in an up-and-down motion, on the page and prints by impact, striking an ink-soaked cloth ribbon against

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720-483: A typewriter that sold for less than $ 50. An automated factory was built near Dallas that took less than 30 minutes to assemble a Xerox typewriter. The Xerox typewriter was well received but never achieved the projected sales numbers due to the advent of the PC and word processing software. The typewriter was later modified to be compatible with PCs but the engineering which made it a low cost device reduced its flexibility. By

780-487: Is an impact printing technology invented in 1970 by Andrew Gabor at Diablo Data Systems . It uses interchangeable pre-formed type elements, each with typically 96 glyphs , to generate high-quality output comparable to premium typewriters such as the IBM Selectric , but two to three times faster. Daisy wheel printing was used in electronic typewriters , word processors and computers from 1972. The daisy wheel

840-553: Is fanfolded and perforated so that pages can be easily torn from each other. In 1925, Rudolf Hell invented the Hellschreiber , an early facsimile -like dot matrix –based teletypewriter device, patented in 1929. Between 1952 and 1954 Fritz Karl Preikschat filed five patent applications for his teletype writer 7 stylus 35 dot matrix aka PKT printer, a dot matrix teletypewriter built between 1954 and 1956 in Germany. Like

900-408: Is gradually supplanting them in some of these applications, but full-size dot-matrix impact printers are still used to print multi-part stationery . For example, dot matrix impact printers are still used at bank tellers and auto repair shops, and other applications where use of tractor feed paper is desirable such as data logging and aviation . Most of these printers now come with USB interfaces as

960-547: Is not customary to call them dot matrix printers. Dot matrix printers have one of the lowest printing costs per page. They are able to use fanfold continuous paper with tractor holes. Dot matrix printers create noise when the pins or typeface strike the ribbon to the paper, and sound-damping enclosures may have to be used in quiet environments. They can only print lower-resolution graphics, with limited color performance, limited quality, and lower speeds compared to non-impact printers. The common serial dot matrix printers use

1020-449: Is possible to use multiple fonts within a document: font changing is facilitated by printer device drivers which can position the carriage to the center of the platen and prompt the user to change the wheel before continuing printing. However, printing a document with frequent font changes requiring frequent wheel changes quickly became tedious. Many daisy wheel machines offer a bold type facility, accomplished by double- or triple-striking

1080-526: Is so named because of its resemblance to the daisy flower . By 1980 daisy wheel printers had become the dominant technology for high-quality text printing, grossly impacting the dominance of manual and electric typewriters , and forcing dominant companies in that industry, including Brother and Silver Seiko to rapidly adapt — and new companies, e.g., Canon and Xerox , to enter the personal and office market for daisy wheel typewriters. The personal and office printing industry would soon adapt again to

1140-509: The LA30 , as did Centronics (then of Hudson , New Hampshire ): the Centronics 101. The search for a reliable printer mechanism led it to develop a relationship with Brother Industries, Ltd of Japan , and the sale of Centronics-badged Brother printer mechanisms equipped with a Centronics print head and Centronics electronics. Unlike Digital, Centronics concentrated on the low-end line printer marketplace with their distinctive units. In

1200-746: The dye-sublimation printer entered the market. In 1968, the Japanese manufacturer OKI introduced its first serial impact dot matrix printer (SIDM), the OKI Wiredot. The printer supported a character generator for 128 characters with a print matrix of 7 × 5. It was aimed at governmental, financial, scientific and educational markets. For this achievement, OKI received an award from the Information Processing Society of Japan (IPSJ) in 2013. In 1970 Digital Equipment Corporation (DEC) introduced an impact dot matrix printer ,

1260-421: The "period" character). This required a mechanism capable of pixel by pixel movement, both horizontally and vertically, and low-end printers were incapable of it. Given the slow speed and the coarse resolution this was not a feasible technique for printing large images. However, it could usefully print a small logo onto a letterhead and then the following letter, all in a single unattended print run without changing

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1320-491: The 1980s. As carriage speed increased and dot density increased (from 60 dpi up to 240 dpi), with some adding color printing, additional typefaces allowed the user to vary the text appearance of printouts. Proportional-spaced fonts allowed the printer to imitate the non-uniform character widths of a typesetter, and also darker printouts. 'User-downloadable fonts' gave until the printer was powered off or soft-reset. The user could embed up to two NLQ custom typefaces in addition to

1380-506: The MX) were notoriously loud during operation, a result of the hammer-like mechanism in the print head. The MX-80 even inspired the name of a noise rock band . The MX-80's low dot density (60 dpi horizontal, 72 dpi vertical) produced printouts of a distinctive "computerized" quality. When compared to the crisp typewriter quality of a daisy-wheel printer, the dot-matrix printer's legibility appeared especially bad. In office applications, output quality

1440-532: The OPD focused on developing and selling the Diablo 630 which was mostly bought by companies such as Digital Equipment Corporation . The Diablo 630 could produce letter quality output as good as that produced by an IBM Selectric or Selectric-based printer, but at lower cost and double the speed. A further advantage was that it supported the entire ASCII printing character set. Its servo-controlled carriage also permitted

1500-509: The US in 1957 he sold the rights to utilize the applications in any country (except the USA) to TuN. The prototype was also shown to General Mills in 1957. An improved transistorized design became the basis for a portable dot matrix facsimile machine, which was prototyped and evaluated for military use by Boeing around 1966–1967. IBM marketed its first dot matrix printer in 1957, the same year that

1560-420: The advent of the PC and word processing software. Dot-matrix impact , thermal , or line printers were used where higher speed or image printing were required and where their print quality was acceptable. Both technologies were rapidly superseded for most purposes when dot-based printers, in particular laser and ink jet printers , capable of printing any characters, graphics, typefaces or fonts, rather than

1620-435: The area of fonts, print enhancements and graphics". Near letter-quality is a form of impact dot matrix printing . What The New York Times called " dot-matrix impact printing ", was deemed almost good enough to be used in a business letter Reviews in the later 1980s ranged from "good but not great" to "endowed with a simulated typewriter-like quality". By using multiple passes of the carriage, and higher dot density,

1680-503: The basic LA36 line into a wide variety of dot matrix printers. The DEC LA50 was designed to be a "compact, dot matrix" printer. When in graphic mode (as opposed to text mode), the printhead can generate graphic images. When in ( bitmap ) graphics mode, the LA50 can receive and print Sixel graphics format. The Centronics 101 (introduced 1970) was highly innovative and affordable at its inception. Some selected specifications: The IBM 5103

1740-450: The carriage return period, characters were buffered for subsequent printing at full speed during a catch-up period. The two-tone buzz produced by 60-character-per-second catch-up printing followed by 30-character-per-second ordinary printing was a distinctive feature of the LA36, quickly copied by many other manufacturers well into the 1990s. Most efficient dot matrix printers used this buffering technique. Digital technology later broadened

1800-412: The carriage, and higher dot density, the printer could increase the effective resolution. In 1985, The New York Times described the use of " near letter-quality, or NLQ" as "just a neat little bit of hype" but acknowledged that they "really show their stuff in the area of fonts, print enhancements and graphics." NLQ printers could generally be set to print in "draft mode", in which case a single pass of

1860-482: The characters of a line while the print head moves horizontally. The printing speed of serial dot matrix printers with moving heads varies from 30 to 1550 characters per second (cps) . In a considerably different configuration, so called line dot matrix printers or line matrix printers use a fixed print head almost as wide as the paper path utilizing a horizontal line of thousands of pins for printing. Sometimes two horizontally slightly displaced rows are used to improve

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1920-533: The cost of speed. Dot matrix printing is typically distinguished from non-impact methods, such as inkjet , thermal , or laser printing , which also use a bitmap to represent the printed work. These other technologies can support higher dot resolutions and print more quickly, with less noise. Unlike other technologies, impact printers can print on multi-part forms , allowing multiple copies to be made simultaneously, often on paper of different colors. They can also employ endless printing using continuous paper that

1980-403: The daisy wheel to position the required character between the hammer and the ribbon. The solenoid -operated hammer then fires, driving the character type onto the ribbon and paper to print the character on the paper. The daisy wheel and hammer are mounted on a sliding carriage similar to that used by dot matrix printers . Different typefaces and sizes can be used by replacing the daisy wheel. It

2040-510: The earlier Hellschreiber, it still used electromechanical means of coding and decoding, but it used a start-stop method ( asynchronous transmission ) rather than synchronous transmission for communication. In 1956, while he was employed at Telefonbau und Normalzeit GmbH ( TuN , later called Tenovis ), the device was offered to the Deutsche Bundespost (German Post Office), which did not show interest. When Preikschat emigrated to

2100-481: The effective dot density through interleaving. While still line-oriented, these printers for the professional heavy-duty market effectively print a whole line at once while the paper moves forward below the print head. Line matrix printers are capable of printing much more than 1000 cps, resulting in a throughput of up to 800 pages per hour. A variation on the dot matrix printer was the cross hammer dot printer, patented by Seikosha in 1982. The smooth cylindrical roller of

2160-533: The first commercially successful daisy wheel printer, a device that was faster and more flexible than IBM's Selectric devices, being capable of 30 cps (characters per second), whereas the Selectric operated at 13.4 cps. Andrew Gabor was issued two patents for the invention and. Xerox acquired Diablo that same year. Xerox's Office Product Division had already been buying Diablo printers for its Redactron text editors. After 7 years trying to make Diablo profitable,

2220-622: The market (e.g. IBM 6640 inkjet, Xerox 2700 and IBM 6670 laser). From 1981 onwards the IBM PC 's introduction of " Code page 437 " with 254 printable glyphs (including 40 shapes specifically for drawing forms), and development of Xerox Star -influenced environments such as the Macintosh , GEM and Windows made bit-mapped approaches more desirable, driving cost reductions for laser printing and higher resolution for impact dot matrix printing. Xerox later adapted Diablo's daisy wheel technology into

2280-413: The mid-1980s daisy wheel technology was rapidly becoming obsolete due to the growing spread of affordable laser and inkjet machines, and daisy wheel machines soon disappeared except for the small remaining typewriter market. The heart of the system is an interchangeable metal or plastic "daisy wheel" holding an entire character set as raised characters moulded on each "petal". In use a servo motor rotates

2340-483: The paper by half of the vertical dot pitch (1/144 inch), then the print head would make a second pass. For 240 by 216 dots/inch, the print head would make three passes with smaller paper movement (1/3 vertical dot pitch, or 1/216 inch) between the passes. To cut hardware costs, some manufacturers merely used a double strike (doubly printing each line) to increase the printed text's boldness, resulting in bolder but still jagged text. In all cases, NLQ mode incurred

2400-426: The paper, much like the print mechanism on a typewriter . However, unlike a typewriter or daisy wheel printer , letters are drawn out of a dot matrix, and thus, varied fonts and arbitrary graphics can be produced. Each dot is produced by a tiny metal rod, also called a "wire" or "pin", which is driven forward by the power of a tiny electromagnet or solenoid , either directly or through small levers (pawls). Facing

2460-437: The print element. Daisy wheel printers are capable of producing simplified graphics in the form of ASCII art . Consideration was also given to optimising graphic printing by changing the glyphs on the daisy wheel to a set that would be able to print all the required bitmap combinations more quickly, without requiring an impact for every single dot. This would have the advantage that vertical dot combinations could be printed in

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2520-408: The print head per line would be used. This produced lower quality print at much higher output speed. In 1985, PC Magazine wrote "for the average personal computer user dot matrix remains the most workable choice". At the time, IBM sold Epson 's MX-80 as their IBM 5152. Another technology, inkjet printing , which uses the razor and blades business model (give away the razor handle, make money on

2580-421: The print head to its starting point. This was sometimes known as 'logic seeking,' and was a feature on some dot-matrix printers as well. Although the daisy wheel principle is basically inappropriate for printing bitmap graphics , there were attempts to enable them to do so. Most daisy wheel printers supported a relatively coarse and extremely slow graphics mode by printing the image entirely out of dots (formed by

2640-469: The printer could increase the effective resolution. For example, the Epson FX-86 could achieve a theoretical addressable dot-grid of 240 by 216 dots/inch using a print head with a vertical dot density of only 72 dots/inch, by making multiple passes of the print head for each line. For 240 by 144 dots/inch, the print head would make one pass, printing 240 by 72 dots/inch, then the printer would advance

2700-406: The printer's built-in (ROM) typefaces. The desktop impact printer was gradually replaced by the inkjet printer . When Hewlett-Packard 's US patent 4578687   expired on steam-propelled photolithographically produced ink-jet heads in 2004, the inkjet mechanism became available to the printer industry. For applications that did not require impact (e.g. carbon-copy printing), the inkjet

2760-624: The process, they designed the parallel electrical interface that was to become standard on most printers until it began to be replaced by the Universal Serial Bus ( USB ) in the late 1990s. DEC was a major vendor, albeit with a focus on use with their PDP minicomputer line. Their LA30 30 character/second (CPS) dot matrix printer, the first of many, was introduced in 1970. In the mid-1980s, dot-matrix printers were dropping in price, and began to outsell daisywheel printers , due to their higher speed and versatility. The Apple ImageWriter

2820-717: The razor blade) has reduced the value of the low cost for the printer: "a price per milliliter on par with liquid gold" for the ink/toner. In June 1978, the Epson TX-80/TP-80, an 8-pin dot-matrix printer mainly used for the Commodore PET computer, was released. This and its successor, the 9-pin MX-80/MP-80 (introduced in 1979–1980), sparked the popularity of impact printers in the personal computer market. The MX-80 combined affordability with good-quality text output (for its time). Early impact printers (including

2880-435: The ribbon and the paper is a small guide plate named ribbon mask holder or protector, sometimes also called butterfly for its typical shape. It is pierced with holes to serve as guides for the pins. The plate may be made of hard plastic or an artificial jewel such as sapphire or ruby . The portion of the printer that contains the pin is called the print head. When running the printer, it generally prints one line of text at

2940-419: The same effect as the more expensive servo-based printers, with the unique side effect that as the printer ages and wears, bold text becomes bolder. Like all other impact printers, daisy wheel printers are noisy. Most daisy-wheel printers could print a line and then, using built-in memory, print the following line backwards, from right to left. This saved the time that otherwise would have been needed to return

3000-418: The specified character(s); servo -based printers advance the carriage fractionally for a wider (and therefore blacker) character, while cheaper machines perform a carriage return without a line feed to return to the beginning of the line, space through all non-bold text, and restrike each bolded character. The inherent imprecision in attempting to restrike on exactly the same spot after a carriage return provides

3060-547: The use of proportional spaced fonts, where characters occupy a different amount of horizontal space according to their width. The Diablo 630 was so successful that virtually all later daisy wheel printers, as well as many dot matrix printers and even the original Apple Laserwriter either copied its command set or could emulate it. Daisy wheel printers from Diablo and Qume were the dominant high-end output technology for computer and office automation applications by 1980, though high speed non-impact techniques were already entering

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3120-430: Was a 30 character per second dot matrix printing terminal introduced in 1970 by Digital Equipment Corporation (DEC) of Maynard, Massachusetts It printed 80 columns of uppercase-only 7 × 5 dot matrix characters across a unique-sized paper. The printhead was driven by a stepper motor and the paper was advanced by a noisy solenoid ratchet drive. The LA30 was available with both a parallel interface (LA30-P) and

3180-430: Was a popular consumer dot matrix printer in the 1980s until the mid-1990s. In the 1970s and 1980s, dot matrix impact printers were generally considered the best combination of cost and versatility, and until the 1990s were by far the most common form of printer used with personal and home computers . Increased pincount of the printhead from 7, 8, 9 or 12 pins to 18, 24, 27, or 36 permitted superior print quality, which

3240-604: Was a serious issue, as the dot-matrix text's readability would rapidly degrade with each photocopy generation. Initially, third-party printer enhancement software offered a quick fix to the quality issue. General strategies were: Some newer dot-matrix impact printers could reproduce bitmap images via "dot-addressable" capability. In 1981, Epson offered a retrofit EPROM kit called Graftrax to add this to many early MX series printers. Banners and signs produced with software that used this ability, such as Broderbund 's Print Shop , became ubiquitous in offices and schools throughout

3300-417: Was coined in the 1980s to distinguish NLQ printing from true letter-quality printing, as produced by a printer based on traditional typewriter technology such as a daisy wheel , or by a laser printer . In 1985 The New York Times described the marketing of printers with the terms " near letter-quality , or N.L.Q." as "just a neat little bit of hype", but acknowledged that they "really show their stuff in

3360-456: Was moved by a much-more-capable servo drive using a DC electric motor and an optical encoder / tachometer . The paper was moved by a stepper motor. The LA36 was only available with a serial interface but unlike the earlier LA30, no fill characters were required. This was possible because, while the printer never communicated at faster than 30 characters per second, the mechanism was actually capable of printing at 60 characters per second. During

3420-517: Was necessary for success in Asian markets to print legible CJKV characters . Epson's 24-pin LQ-series rose to become the new de facto standard, at 24/180 inch (per pass – 7.5 lpi). Not only could a 24-pin printer lay down a denser dot-pattern in a single pass, it could simultaneously cover a larger area and print more quickly. Although the text quality of a 24-pin was still visibly inferior to

3480-477: Was never a popular approach. Brother Industries manufactured the Twinriter 5 (1985) and 6 (1987) printers which tried to overcome the limitation of the missing graphics capabilities of daisy wheel printers by adding a dot matrix print head to the existing daisy wheel print head, with the former being used for letter quality printing and the latter for drafts and for printing symbols which were not present in

3540-401: Was superior in nearly all respects: comparatively quiet operation, faster print speed, and output quality almost as good as a laser printer. By 1995, inkjet technology had surpassed dot matrix impact technology in the mainstream market and relegated dot matrix to niche applications. As of 2021, dot matrix impact technology remains in use in devices and applications such as: Thermal printing

3600-510: Was the only IBM printer that could be attached to the IBM 5100 , an early day portable computer. Printing was 8 DPI, 10 pitch, 6 LPI, and capable of printing bidirectionally from a 128-character set. Two models were offered: 80 and 120 characters per second. Near Letter Quality mode—informally specified as almost good enough to be used in a business letter—endowed dot-matrix printers with a simulated typewriter-like quality. By using multiple passes of

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