Patent attributes
An optical object identifying device has a light-emitting device, a first photodetector and a second photodetector. In the optical object identifying device, an angle of 10 to 30 degrees is formed between the optical axis of the light-emitting device and the surface of the sheet to be identified. Also, an angle of 10 to 30 degrees is formed between the optical axis of the first photodetector and the surface of the sheet. Further, an angle of approximately 90 degrees is formed between the optical axis of the second photodetector and the surface of the sheet. Thus, the light-emitting device, the first photodetector and the second photodetector are arranged in the optimum positions, so that the first photodetector and the second photodetector can obtain two output values varied with each of many types of sheets.
