The FUJI XEROX Able 1301a is the first single pass highlight color copier, that produces two color copies
through a single Xerographic process. The Able 1301a provides superior copy quality at a low cost through the
following new unique technologies.
1. Color flag method:
Color flag method reduces image data size. Instead of using a l6bit wide data path, the internal image data
consists of a 1-bit flag, that represents color (black or color) and 8-bit luminance data.
2. Pulse width modulation (PWM) technology in delay line method:
Delay line type PWM does not requires a high frequency video clock which are used for the conventional
digital shift clock type PWM. Besides, the circuits for the delay line PWM cost less and provides less drift than
those for analog circuit PWM.
3. Line screen forming method:
The technique used to generate the screens enables selectively printing with 200 or 400 line screens per
inch for Photo and Text modes using a simple circuit.
4. Statistical process for background suppression:
This technique enables background detection and background area calculation to effectively produce copy
without high background with various types of originals.
Koji Aikawa, Koji Aikawa,
"A new image handling technique for a single pass highlight color copier ", Proc. SPIE 1670, Color Hard Copy and Graphic Arts, (1 May 1992); doi: 10.1117/12.2322263; https://doi.org/10.1117/12.2322263