JPS57130064A - Picture recorder - Google Patents

Abstract

PURPOSE:To ensure the stabilized recording of a half-tone picture, by varying the conducting time of a semiconductor laser diode LDA or the conducting time and the number of laser diodes constituting the LDA and having the emission of light. CONSTITUTION:The (n) units of laser diodes constituting an LDA5 are all simultaneously made to conduct for a time of tp=p/16 while a scan is carried out in the main scanning direction. While the conduction is discontinued for these laser diodes for the rest time of p-p/16. Thus p/16 and p-p/16 are identical to the bright and dark parts respectively to obtain a relative half-tone picture element having an effective product of 1/16 unit picture element XAXXB. Thereafter, the conducting time (tp) is varied as tp=p/8, p/2 and (p) to modulate the area with every unit picture element. As a result, a relative half-tone picture element is obtained. In such way, the light of an LDA received an area modulation with every unit picture element is projected on a photoreceptor and then converted into an electric charge image to carry out the toner development, transcription and heating fixing. Thus a stabilized half-tone picture can be recorded on the ordinary paper.