| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a diffraction element in which a mark pattern for alignment confirmation is formed to facilitate confirmation of an accurate installation of the diffraction element, and an optical module equipped with the diffraction element. <P>SOLUTION: The diffraction element is a diffraction element in which a plurality of diffraction patterns are formed. The diffraction patterns include main diffraction patterns that give diffraction characteristics and mark patterns for alignment position recognition whose pitch is different in size from the pitch of the main diffraction patterns. In the diffraction element, the pitch of the mark patterns is formed so that it is smaller than that of the main diffraction patterns. In the diffraction element, the ratio of the pitch of the mark patterns to the pitch of the main diffraction patterns is 1/8 to 1/2 inclusive. <P>COPYRIGHT: (C)2011,JPO&INPIT |
