Patent ID: 8941904
Filing Date: 2015-01-27
Classification: G03H

Abstract:
1. A method for making a subject to be shielded invisible comprising the steps of: preparing a hologram sheet that comprises a transparent substrate, a hologram layer formed on a front surface of the transparent substrate and having a transmission type Fourier transform hologram region which has a pitch of 20 μm or less and with a function of reconstructing an optical image with a light beam incident from a point light source and a non hologram region which is other than the transmission type Fourier transform hologram region and without the function, and a pressure-sensitive adhesive layer which is formed on either: making a subject to be shielded which is 30 mm in diameter invisible by viewing the subject to be shielded through the hologram sheet, wherein, during the step of making the subject to be shielded invisible, when the subject to be shielded is disposed at a position facing the front surface of the transparent substrate at a distance of 500 mm from the hologram layer, the subject to be shielded is made invisible from a viewing position disposed at a position facing the back surface of the transparent substrate by viewing the subject to be shielded through the transmission type Fourier transform hologram region in the hologram layer.