A multichip page size image sensor

With the advent of digital copiers, there is an increasing need for scanners that can operate at high speed, at a reasonable price, without any loss of image quality. With this application in mind, Xerox has developed a page size image sensor. This device is an in-line multichip module that measures approximately 325×30 mm. It is made of 20 independent VLSI sensor chips mounted end to end on a special printed wiring board substrate. The substrate, the die bonding, and the wire bonding make use of well known materials and techniques. The size of the device, the chip dicing accuracy, and the assembly accuracy are the features that make this device unique. As the sensor length matches the page size, the collection of light is efficient and uniform. Even at scanning speeds of 100 pages per minute or higher, the image quality is exceptional