HP LaserJet: Лазерлік принтерлер тарихы мен дамуы

Brand of laser printers

LaserJet as a brand name identifies the line of laser printers marketed by the American computer company Hewlett Packard (HP). The HP LaserJet was the world's first commercially successful laser printer. 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 the Japanese company Canon. Due to a very tight turnaround schedule on the first HP LaserJet, HP elected to use the controller already developed by Canon for the CX engine in the first HP LaserJet. In spring of 1989 The New York Times said that HP "dominates" the PC laser printer market. HP chose to use their in house developed Printer Command Language (PCL) as opposed to Apple, which adopted 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. It was controlled using PCL3. Due to the high cost of memory, the first LaserJet only had 128 kilobytes of memory, and a portion of that was reserved for use by the controller. The HP LaserJet printer had high print quality, could print horizontally or vertically and produce graphics. 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. Aftermarket replacement scanner assemblies remain available today.

In December 2000 HP shipped its 50 millionth LaserJet printer. In September 2001 HP entered 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) HP 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 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 HP LaserJet sales had reached 100 million. 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 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.

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 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 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 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 HP 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 the network, to attack other computers on the network, or even to cause a printer to intentionally overheat. In September 2015, HP added new features to its printers to address security vulnerabilities, releasing what they called the "World's Most Secure Printers".