| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an off-axis transmission wavefront measuring apparatus with a simple structure which is capable of conducting an performance check for off-axis light from all directions around the optical axis of a lens to be checked in a short time. <P>SOLUTION: On a measurement optical axis C<SB POS="POST">10</SB>, there are arranged a reference standard plate 20 with a diffraction grating, a lens to be checked 70 which is supported by a specimen supporting means 30 and a null optical element 40 in this order. A diffraction optical element 22 included in the reference standard plate 20 with the diffraction grating is configured to convert measurement light from a reference standard plane 21 into off-axis measurement light incident on the lens to be checked 70 from the all directions around an optical axis C<SB POS="POST">70</SB>of the lens to be checked 70 at a predetermined inclination angle with respect to the optical axis C<SB POS="POST">70</SB>. The off-axis measurement light incident on the lens to be checked 70 is retroreflected by the null optical element 40 and turns out light to be checked via the lens to be checked 70 and the reference standard plate 20 with the diffraction grating. An interference fringe image formed by optical interference of the light to be checked and reference light is imaged with an imaging camera 16, and is analyzed by an analysis device 51. <P>COPYRIGHT: (C)2012,JPO&INPIT |
