| 摘要 |
PURPOSE:To obtain a diffraction grating having a multiple interference fringe whose intergrating distance is different, by constituting an optical system of a laser having plural oscillation wavelengths, varying in order the oscillation wavelengths of the laser, and making it expose a photosensitive material. CONSTITUTION:An optical system is formed on a table provided with a vibration resistant structure, a laser beam 1 of 4,880Angstrom is oscillated from a 4W argon laser 4, and is made to expose a silver dry plate 2 at an angle of incidence theta=10 degrees for 1/10sec. Subsequently, a laser beam whose lambda is 5,143Angstrom is oscillated by controlling a wavelength converting prism of the laser, and is made to expose for 1/10sec in the same way. As a result, it is possible to obtain a dry plate which has multirecorded a double interference fringe whose intergrating spaces are about 1.40mum and 1.48mum, respectively. This dry plate is brought to a developing treatment in the same way as treatment of a usual silver salt dry plate, and also is treated by bleaching it in a bromine atmosphere. |
