MASTER HOLOGRAM AND PRODUCTION OF HOLOGRAM FILTER BY USING THE MASTER HOLOGRAM

摘要

PROBLEM TO BE SOLVED: To enable to execute effective interference exposure recording nearly over the entire area on a hologram photosensitive material by providing a master hologram with plural lens pattern regions formed in an array form and non-lens regions filling the spaces therebetween and making the transmittance of exposure light transmitting and advancing rectilinearly through the non-lens regions approximately the same as the transmittance of the exposure light transmitting and advancing rectilinearly through the lens pattern regions. SOLUTION: An amplitude modulation type hologram formed with the lens patterns of a chromium layer which is a light shielding material on the surface is used as the master hologram 13. The lens patterns made smaller in the lens width (opening width) than the lenses on the corresponding hologram filter are arranged in the array form at specified intervals on the surface layer of the master hologram 13 by taking the distance between the master hologram 13 and the hologram photosensitive material 18 into consideration. However, the non-lens regions S1 which are heretofore the complete light shielding parts are formed as half-light shielding layers and the transmittance of the zero order diffracted light (transmitted rectilinearly advancing light) of the non-lens regions is regulated so as to have nearly the same value as the value of the lens pattern regions L1.