Image pickup device

Abstract

Abstract PURPOSE: To prevent the periodic generation of disturbances in an image to be displayed by compensating the angular error of an optical scanning polygonal element due to the working error with the use of a delay circuit. CONSTITUTION: The outer circumference of a cylinder, which is made rotatable together with an optically scanning rotatable polygonal mirror 2, is formed with a non-reflecting portion 7 except for only one portion of a reflecting portion 8 so that roraty signals 11 for detecting a preset one point in the circumferential direction of the mirror 2 are generated by light emitting and receiving elements 9 and 10. If the signals 11 are used as a reference, from which side the signals 12 for metering the reflecting surface of the mirror 2 by the elements 5 and 6 come from is judged so that the signal 12 are separated in accordance with the reflecting surface by means of a synchronous separating circuit 14. As a result, the discrepancy in the scanning synchronous time is corrected with the use of delay circuits 15 of such delay time as accords to the intrinisic angular error of the respective reflecting surfaces of the mirror 2 due to the working error, thus generating correcting synchronous signals from an overlapping circuit 16. Then, the error in an angular indexing operation of the mirror 2 is compensated. As a result, it is possible to accomplish the satisfactory image display having no periodic discrepancy with the use of such mirror which can be easily produced COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Tomomasa Kondo
• 👤 Riichi Saeki
• 👤 Junichiro Yamashita
• 👤 Susumu Takahashi

Bibliographic Details