| 摘要 |
PURPOSE:To form a beam detector with a new constitution suitable for a small sized laser printer, by using an optical fiber for the incidence of laser beam. CONSTITUTION:At the back of a slit 15, an optical fiber 22 is located so that the center axis coincides with the direction of laser beam reflected from a mirror. An end of input light 22a of an optical fiber 22 is inserted to a hole 23a provided at a holding member 23 and fixed with bonding. A holding member 23 is fixed to a fiber fitting plate 24. On the other hand, an end of light output 22b of the optical fiber 22 is located in front of a photodetector 16, which is fitted to a printer control circuit board 26. A laser beam 12 transmitted through an image forming lens 9 is reflected on a mirror 13 and formed in the slit 15 and incident to an optical fiber 22c. Further, the light propagates inside the optical fiber 22 and is incident to the photodetector 16 and produces an output. |
