Patent ID: 6697183
Filing Date: 2004-02-24
Classification: G02B

Abstract:
A light beam scanning apparatus, comprising:light source configured to emit light beams; first optical unit configured to optically couple together said light beams emitted from said light source; second optical unit configured to converge said light beams received from said first optical unit into an approximately line image elongated along a horizontal scanning direction; light beam deflector configured to deflect said light beams received from the second optical unit by interaction with reflecting planes situated at least at a vicinity of a position of formation of said approximately line image; and third optical unit configured to converge said light beams deflected by said light beam deflector into a spot of light formed on a surface to be scanned; wherein said third optical unit includes a first anamorphic optical element and a second anamorphic optical element with each anamorphic optical element having a positive power along the horizontal scanning direction and a vertical scanning direction, respectively; and wherein a magnification of said third optical unit is made approximately constant irrespective of deflection angle and a power of said first anamorphic optical element is also made approximately constant irrespective of deflection angle.