Multi-beam scanning apparatus

A scanning unit of multi-beam scanning apparatus comprising:

• a plurality of semiconductor lasers that emit laser beams;
• a scanner that has an optical system and scans the laser beam emitted from said plurality of semiconductor lasers;
• a plurality of laser drivers that respectively drive a corresponding semiconductor laser among said plurality of semiconductor lasers in accordance with a standard signal and image data fed from a controller that is connected to said scanning unit, the sequence of pulse signals having a plurality of common pulse signal sections that correspond to said plurality of semiconductor lasers, each of said plurality of common pulse signal sections having a peculiar waveform characteristic depending upon a corresponding semiconductor laser;
• a standard voltage generator that converts the sequence of pulse signals to a sequence of standard voltage signals that correspond to said plurality of semiconductor lasers and have a plurality of standard voltage sections;
• and
• a standard voltage setter that detects each of the plurality of common pulse signal sections in accordance with the characteristic, and transmits each value of the plurality of standard voltage sections to a corresponding laser driver in accordance with a detected common pulse signal section, each of said plurality of laser drivers controlling the corresponding semiconductor laser in accordance with a value of a corresponding standard voltage section.

A multi-beam scanning apparatus comprising:

• a plurality of light sources that respectively emit beam;
• a plurality of driving circuits that correspond to said plurality of light sources and respectively drive a corresponding light source;
• an exposure unit that has an optical system and scans laser-beams emitted from said plurality of light sources;
• a controller that generates a sequence of pulse signals corresponding to said plurality of light sources, said sequence of pulse signals being output via single control signal line;
• and
• a control value setter that sets a control value for each of said plurality of driving circuits in accordance with the sequence of pulse signals,
• wherein said plurality of driving circuits respectively drive the corresponding light source in accordance with the corresponding control value.

A multi-beam scanning apparatus comprising:

• a scanning unit that has a plurality of semiconductor lasers and drives said plurality of semiconductor lasers separately;
• and
• a controller that generates a sequence of control signals and transmits the sequence of control signals to said scanning unit, said Scanning unit being connected to said controller via a single control signal line for transmitting the sequence of control signals;
• wherein said scanning unit detects a plurality of control values corresponding to said plurality of semiconductor lasers from the sequence of control signals, and drives each of said plurality of semiconductor lasers in accordance with a corresponding control value.