CONTACT TYPE SENSOR

PURPOSE:To eliminate an assembly process and wirings between unit parts and obtain a contact type sensor which is small in size and light in weight by a method wherein a light emitting device array, a photodetector array, a light emitting device driving circuit and an amplifier for photodiodes are formed on a semiconductor substrate as a monolithic IC. CONSTITUTION:A contact sensor is constituted by forming an LED array 12, a photodiode array 13, an LED driving circuit 14 and an amplifier 15 for photodiodes on a silicon substrate 11 as a monolithic IC. Wirings 16 and 17 connect between the LED array 12 and the LED driving circuit 14 and between the photodiode array 13 and the amplifier 15 for the photodiodes respectively. With this constitution, driving of the light emitting device array 12, light application to a manuscript, photodetection of reflected light and amplification of photodetection output can be performed on one semiconductor substrate 11 and wirings between unit parts can be eliminated so that size reduction and weight reduction can be achieved.