| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a diffractive-optical element capable of generating a dispersive light spot, and provide a measuring device. <P>SOLUTION: A diffractive-optical element includes convexoconcave and generates a diffracted light by diffracting an incident light in a two-dimensional manner. When the number of partial or entire light spot formed by the diffracted light is set as n, an average nearest neighbor distance W at the light spot that is standardized by an area of a region where the light spot is illuminated is within a range of 1/(2×n<SP POS="POST">1/2</SP>)<W<1/(n<SP POS="POST">1/2</SP>). <P>COPYRIGHT: (C)2012,JPO&INPIT |
