| 摘要 |
PURPOSE:To enable correction or control of the sensitivity of a photosensitive body even if the oscillation wavelength of a laser fluctuates by constituting a laser light detecting means of such a single laser light detecting means which has roughly the same spectral sensitivity characteristic of an image receiving part, i.e., the photosensitive body. CONSTITUTION:A laser light detecting element 10 is disposed on the extension of the laser beam scanning line at one end in the axial direction of a photosensitive drum 9, whereby the detected output of the laser light meeting the actual environment in which the drum 9 is placed is obtd. The element 10 is formed of a photosensitive material having roughly the same spectral sensitivity characteristic as that of the drum 9. The control signal from the laser light output of a lead 23 is corrected to the fresh control signal value for the laser light output at every scanning by such constitution in order to compensate the substantial fluctuation in the laser light output and the relative fluctuation in the laser light output viewed from the photodetecting part occurring in the fluctuation in the laser oscillation wavelength in accordance with the laser light detection output detected at the beginning of each scanning line by the laser beam. The always stably exposed image is eventually obtd. on an image receiving part, i.e., the drum 9. |
