[1][2] It was originally designed to compliment the company's LaserJet series of laser printers and allowed HP to compete in the burgeoning desktop publishing market of the 1980s.

The grayscale-only ScanJet Plus, co-developed with Canon and released in 1989, was a massive commercial success and had a wide influence in scanner design.

For almost a decade at the low end of the market, the ScanJet Plus was a de facto standard for the specifications of scanner hardware.

[8] The original ScanJet has a 8.5-by-13-inch platen and is capable of scanning at a maximum resolution of 300 dpi in 4-bit grayscale (16 shades of gray).

[9][10] The original ScanJet has an internal raster image processor (RIP), controlled by software, capable of outputting the scan to the computer in raw 4-bit grayscale, in halftone dither, or in 1-bit monochrome.

[10][12] Customers were forced to buy a proprietary interface card that allowed the ScanJet to connect to an IBM PC or compatible desktop computer for nearly US$500 extra.

[14] The original ScanJet sold very well for HP,[13] with PC Week calling it a "mammoth succes[s]" six months after its initial release.

[15] By the beginning of 1988, the ScanJet had accounted 27 percent of all scanner sales in terms of dollar volume, per Gartner Dataquest.

[16] Canon's IX-12 had heretofore been the most popular scanner for the PC platform, but by 1989 the ScanJet had caught up in terms of sales and third-party software support.

[31][32] The CCDs are refreshed periodically to eliminate low-pass filtering at the scanner's native 400 dpi, increasing vertical resolution.

When scanning at lower resolutions, however, the sensor traverses the page at a faster rate, inducing a slight low-pass filter over the image (in an analog fashion) and eliminating aliasing effects on half-tone images, a beneficial side-effect when scanning halftone-printed originals.

Thus, HP designed the ScanJet IIC's stepper motor drive system to occasionally stop the imaging sensor in place and ratchet it back several millimeters to allow for the disk buffer to clear and the scan to restart.

[26][33] The ratcheting motion prevents gaps and other distortions in the final output by accounting for the inertia of the image sensor suddenly stopping in place.

It was also HP's first ScanJet to ship with an optional transparency adapter, used for scanning slides and film negatives.

[38] HP bundled the ScanJet IIp with a trial version of Caere's OmniPage, an optical character recognition (OCR) software package.

This boost in bit depth aids in post-processing of images; for example, it allows the user to pull out detail from shadows in dark photographic prints while reducing banding.

[45][46] It was virtually identical to the 3c, with the bundled DeskScan II scanner control and raster editor application updated for greater Windows 95 support.

[49] Development of the ScanJet 3c was an involved process, requiring tweaking the sizes of each of the three-strip CCD sensor to correct for chromatic aberration caused by uneven path lengths of the filtered red, green, and blue beams of light as they bounce off the mirrors of the optical assembly.

HP also had to design and manufacture a bespoke fluorescent tube with three specific phosphors that radiate even, controlled amounts of red, green, and blue light.

[53][55] PC Magazine reviewed the ScanJet 5s negatively, writing that, "Unfortunately, [HP's] first entry in the color sheet-fed scanner market ... is slow and noisy", outputting mediocre scans.

On a cold power-on, holding down the scan button when the SCSI ID selector on the back is set to "0" will cause the ScanJet to play a rendition of Schiller's "Ode to Joy", by modulating the speed of the audible stepper motor drive to produce specific pitches.

With a local interface comprising an LCD and a numeric keypad, the ScanJet can be controlled directly to send files to any computer on the network.

[78] The ScanJet 5530, a more traditional image scanner, bumped the color depth to 48 bits and included a miniature ADF for 4-by-6-inch prints.