Patent ID: 8703363
Filing Date: 2014-04-22
Classification: G03F,G03H

Abstract:
1. A method for recording a volume reflection holographic image in a transparent holographic recording medium comprising a photochemically active dye dispersed in a polymer binder having a refractive index n, said holographic recording medium being photosensitive to external light provided at a wavelength W of 300-500 nm; disposing a first transparent prism having a first prism first surface optically coupled with a first surface of the holographic recording medium and a first prism second surface at about a 45° angle to the first prism first surface, and exposing the holographic recording medium to a first signal coherent light source that includes image or other information to be recorded in the holographic recording medium and a first reference coherent light source, said first signal coherent light source and first reference coherent light source emitting light at the wavelength W such that light from one of the first signal and reference coherent light sources enters the first prism through the first prism second surface and exits the first prism through the first prism first surface to enter the holographic recording medium through the first surface, and light from the other of the first signal and reference coherent light sources enters a second opposing surface of the holographic recording medium to produce a holographic image viewable at an angle of incidence S disposing a second transparent prism having a second prism first surface optically coupled with the first surface of the holographic recording medium and a second prism second surface at about a 45° angle to the second prism first surface, and exposing the holographic recording medium to a second signal coherent light source that includes image or other information to be recorded in the holographic recording medium and a second reference coherent light source, said second signal coherent light source and second reference coherent light source emitting light at the wavelength W such that light from one of the second signal and reference coherent light sources enters the second prism through the second prism second surface and exits the second prism through the second prism first surface to enter the holographic recording medium through the first surface, and light from the other of the second signal and reference coherent light sources enters the second opposing surface of the holographic recording medium to produce a holographic image viewable at an angle of incidence S disposing a third transparent prism having a third prism first surface optically coupled with the first surface of the holographic recording medium and a third prism second surface at about a 90° angle to the third prism first surface, disposing a fourth transparent prism having a fourth prism first surface optically coupled with the second opposing surface of the holographic recording medium and a fourth prism second surface at about a 45° angle to the fourth prism first surface, and exposing the holographic recording medium to a third signal coherent light source that includes image or other information to be recorded in the holographic recording medium and a third reference coherent light source, said third signal coherent light source and third reference coherent light source emitting light at the wavelength W such that light from one of the third signal and reference coherent light sources enters the third prism through the third prism second surface and exits the third prism through the third prism first surface to enter the holographic recording medium through the first surface, and light from the other of the third signal and reference coherent light sources enters the fourth prism through the fourth prism second surface and exits the fourth prism through the fourth prism first surface to enter the holographic recording medium through the second opposing surface of the holographic recording medium to produce a holographic image viewable at an angle of incidence S