| 摘要 |
PURPOSE:To reduce a transition area of a phase shift part with an easy process by calculating interference fringes for the interference between a diffraction wave front, which is obtained by projecting obliquely incident parallel rays of light to a calculated phase plate which generates a desired phase shift, and a calculated reference luminous flux to form a ruggedness on a substrate. CONSTITUTION:Interference fringes between the diffraction wave front on a hologram face 4 of a uniform plane wave 2 due to a virtual phase plate 5 and a reference light 6 are calculated. For the purpose of reducing transition areas in phase shift parts, the diffraction wave front in phase shift parts of the phase plate is taken in a sufficient wide range to perform calculation. Calculated interference fringes are described by an electron beam describing device, and a chromium pattern is formed by etching and is used as a mask to transfer the pattern to a photo resist on the substrate, and thereafter, the photo resist pattern is used as a mask to form the pattern by etching. Thus, a phase shift diffraction grating which has small transition areas in phase shift parts and has an optional period is produced with the simple process.
|
