A contact-type linear sensor with a GD a-Si:H photodetector array

A 512-element contact-type linear sensor using glow discharge-produced a-Si: H as a photo-sensor material has been developed. The sensor, comprised of a sensor plate and a compact optical system, measures 80mm × 46mm × 20mm. The sensor plate is a pyrex glass substrate on which a-Si:H photodetector array is formed and 4 MOS IC chips are mounted. Elastomer connectors were used to connect the electrodes of the photodetectors to the corresponding pads on the IC chips, allowing us to make the linear sensor very compact. The optical system has a rod lens array and two tungsten lamps as a light source. This new linear sensor provides a satisfactory image with a resolution of 7 lines/mm and an S/N ratio of at least 20 dB on a memory scope or on a printer.