| 摘要 |
PURPOSE:To obtain a small-sized, high-precision rotary polyhedral lens body by using a transparent body having circumferential surface formed of plural hyperbolic lines. CONSTITUTION:A rotary polyhedral lens body 1 for optical deflection consists of a regular octagonal prism having eight concave circumferential surfaces 1-i (i=1-8) formed of hyperbolic lines P. The equation of each hyperbolic line P is y<2>=(n<2>-1)x<2>-2nAx+A<2> (where n is the refractive index of the lens body 1). A light beam when caused to strike an axis O of rotation (perpendicular to the paper surface) at an angle alpha to a line Y-Y is made parallel to the line Y-Y in the lens body 1 and emitted at the angle alpha to the line Y-Y. For the purpose, the lens body 1 is rotated to deflect the emitted beam. |
