Edge intensifying device

Abstract

Abstract PURPOSE:To clearly reproduce a fine line or the like in a device for digitally modulating and recording a laser beam by intensifying only the laser modulation current at the edge of a digital signal. CONSTITUTION:Laser beam from a laser oscillator is irradiated to the surface of a photosensitive drum as a photosensitive medium, and a latent image is formed on the medium. When the beam is repeated in oscillation and stoppage using the digital signal, the spot of the beam becomes smooth at the periphery of the signal and accordingly similarly becomes smooth at the medium. The device circuit is composed of a laser modulator circuit 3, a phase shifter 4, an exclusive OR gate 5, a semiconductor laser LD, and transistors Q1, Q2. Thus, the output of the laser LD is modulated at the transistor Q1, is superimposed at the transistor Q2, thereby increasing the laser drive current at the edge larger than the part except the edge. The resistors R1, R2 at the collectors of the transistors Q1, Q2 are set by R1>>R2.

Inventors

• 👤 Yukio Sato

Bibliographic Details