Patent ID: 6523963
Filing Date: 2003-02-25
Classification: G02B,Y10S

Abstract:
A diffraction optical element comprising:a first optical member having a first diffraction grating; a second optical member having a second diffraction grating, wherein the first and second optical members are stacked so that the first and second diffraction gratings face each other inside the stacked members and so that a space is formed between the diffraction gratings; and a sealing member for hermetically sealing the space between the diffraction gratings, wherein a convex part for performing relative positioning with the second optical member is formed in an outer peripheral portion of the first optical member, and a concave part for fitting with the convex part of the first optical member is formed in an outer peripheral portion of the second optical member and wherein a gap is provided at an outside of the convex part and the concave part which mutually fit between the first and second optical members, and the gap is filled up with a sealing member.