| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an illuminating optical system in which brightness on an illuminated surface is almost uniform even though the angle distribution of a luminous flux on a specific cross-section is made small, and which is hardly affected by the nonuniform luminance of a light source and is high in the availability of light ray. <P>SOLUTION: The illuminating optical system divides a luminous flux from a light source 1 into a plurality of first luminous fluxes at least in a first cross-section (XZ cross-section), and causes the plurality of first luminous fluxes to overlap one another on an illuminated surface. The optical system that divides the luminous flux from the light source includes, in order from the light source side, a first lens array 6 and a second lens array 7, each having a plurality of eccentric lens cells. The first and second lens array have refractive powers the signs of which are the same. In addition, the faces in which the lens cells of the first and second lens arrays are formed are directed in the same direction. <P>COPYRIGHT: (C)2007,JPO&INPIT |
