Patent ID: 6426767
Filing Date: 2002-07-30
Classification: G03G,H04N

Abstract:
An image forming apparatus for selectively outputting color and monochrome images comprising:a first light beam generator to generate a first light beam; a second light beam generator to generate a second light beam; a scanner to control the first and second light beams generated by the first and second beam generators, respectively, for scanning; a first scanning state changer to change a scanning state of the first light beam; a second scanning state changer to change a scanning state of the second light beam; a first member to be exposed, scanned with the first light beam or both the first and second light beams while the first member transferring in a perpendicular direction with respect to a beam scanning direction; a second member to be exposed, scanned with the second light beam while the second member transferring in a perpendicular direction with respect to a beam scanning direction; a first mode image generator to scan the first member to be exposed with the first and second light beams, thus generating a monochrome image in a first image formation mode; a second mode image generator to scan the first member to be exposed with the first light beam and scan the second member to be exposed with the first light beam and scan the second member to be exposed with second light beam, thus generating a color image in a second image formation mode; a first light beam detector to detect the scanning state of the first beam or the first and second light beams to the first member to be exposed; a second light beam detector to detect the scanning state of the second light beam to the second member to be exposed; a selector to select either the first image formation mode or the second image formation mode; and a controller, in the first image formation mode, to detect the scanning state of the first and second light beams to the first member to be exposed through the first detector, thus controlling the first and second scanning state changers so that each light beam is set in a certain scanning state, in the second image formation mode, to detect the scanning state of the first light beam to the first member to be exposed through the first detector and detect the scanning state of the second light beam to the second member to be exposed through the second detector, thus controlling the first and second scanning state changers so that each light beam is set in a certain scanning state; wherein the first and second scanning state changers change image magnification of each light beam.