Diffractive optical element and image reader using the same
First Claim
1. A diffraction optical element formed by laminating a plurality of diffraction gratings having a plurality of grating surfaces, wherein two non-overlapping grating surfaces adjacent to each other along an incident direction of a light satisfy the following relation:
1 Assignment
0 Petitions
Accused Products
Abstract
A laminate-type diffractive optical element which is easily producible and which allows high optical performance to be easily achieved, and an optical system using the same, are disclosed. In the diffractive optical element formed by laminating a plurality of diffraction gratings, when the distance between the uppermost portion of one diffraction grating and the lowermost portion of the other diffraction grating in two diffraction gratings adjacent to each other along the incident direction of a light is represented by D (μm), these two diffraction gratings are arranged to satisfy the following relation: 10 μm<D<40 μm.
-
Citations
13 Claims
- 1. A diffraction optical element formed by laminating a plurality of diffraction gratings having a plurality of grating surfaces, wherein two non-overlapping grating surfaces adjacent to each other along an incident direction of a light satisfy the following relation:
Specification