| 摘要 |
PCT No. PCT/EP89/01157 Sec. 371 Date Jun. 1, 1990 Sec. 102(e) Date Jun. 1, 1990 PCT Filed Oct. 2, 1989 PCT Pub. No. WO90/03867 PCT Pub. Date Apr. 19, 1990.A optical profile reader, particularly for key duplicating machines, incorporationg a photoemitter (16) positioned on one side of the profile (11) to be read, and a photodetector (21) facing the photoemitter (16), but on the opposite side of the profile to be read. Stepper motors (5, 8) are included for causing the profile (11) to be read to move orthogonal to the direction of a light beam striking the profile to be read. An electronic circuit controlled by the output signal of the photodetector (21) is also provided. The electronic circuit uses a threshold discriminator (25) set at a value between the values corresponding to the maximum and minimum illumination states of the photodector (21). The threshold discrimination circuit (25) also controls the operation of the stepper motors (5, 8). |
