Image forming apparatus and method therefor

An image forming apparatus for forming an image on a recording medium by scanning a laser beam on said recording medium including:

• an area designating means for designating respective areas responsive to halftone and character images of a document,
• a reading means for reading an image of the document and outputting analog image signals having a plurality of gradations,
• an amplifier means for amplifying said analog signals,
• a laser emitting means for scanning a laser beam on said recording medium so as to produce an image of the original on said recording medium,
• a driving means for supplying an energizing current responsive to said analog signals amplified to said laser emitting means, and
• an altering means for altering the gain of said amplifier means so as to amplify image signals responsive to said halftone image area at a first amplification degree and image signals responsive to said character image at a second amplification degree higher than the first one.

An image forming method for an image forming apparatus which forms an image on a recording medium by scanning a laser beam on said recording medium including the following steps:

• reading an image of a document including a halftone image area and a character image area and outputting analog image signals having a plurality of gradations,
• amplifying image signals responsive to a halftone image area at a first amplification degree and image signals responsive to said character image area at a second amplification degree higher than the first one,
• supplying an energizing current responsive to said image signals amplified to said laser emission means, and
• scanning a laser beam on said recording medium in base of said energizing current,
• whereby forming an image corresponding to the document on said recording medium.

An image forming method for an image forming apparatus which forms an image on a recording medium by scanning a laser beam on said recording medium including the following steps:

• outputting primary analog image signals responsive to the density of a document,
• converting said primary analog image signals to primary digital image signals,
• performing a predetermined .gamma.-correction to said primary digital image signals to convert them to secondary digital image signals,
• converting said secondary digital image signals to secondary analog image signals,
• amplifying secondary analog image signals responsive to said halftone image area at a first amplification degree and those responsive to said character image area at a second amplification degree higher than the first one and
• supplying an energizing current responsive to said secondary analog image signals to said laser emission device
• scanning a laser beam on said recording medium in base of said energizing current,
• whereby forming an image corresponding to the document on said recording medium.