Spatial frequency carrier and process of preparing same

• US 4,017,158 A
• Filed: 03/17/1975
• Issued: 04/12/1977
• Est. Priority Date: 03/17/1975
• Status: Expired due to Term

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Booth, Bruce Lee
• Primary Examiner(s): Stern, Ronald J.
• Application Number:
  US05/559,168
• Time in Patent Office: 757 Days
• Field of Search: 350/3.5, 350/162 SF, 96/27 H, 96/35.1, 353/31
• US Class Current: 359/567
• CPC Class Codes: G02B 27/4294 in multispectral systems, e.g. UV and visible
• CPC Class Codes: G02B 5/1828 having means for producing variable diffraction controlling the direction of light by means of one or more diffracting elements G02B26/0808; acousto-optical elements G02F1/11, G02F1/33; electro- or magneto-optical diffraction G02F1/292, G02F1/2955

Abstract

A transparency for reproducing preselected area delineations in colors and intensities thereof variable at will is formed by using an interference pattern formed holographically by the interference of a split laser beam. The transparency has a plurality of mutually exclusive areas each individual area representing a variable color wherein the area or areas representing a particular variable color contains spatial frequency carriers which are oriented differently from the spatial frequency carriers of the other areas. The holographic process of preparing the transparency by separately exposing each area in a different orientation to the interference of the two said laser beams is also disclosed. The process and apparatus for utilizing the separation transparency to form predetermined images wherein the color of the individual areas and the intensity thereof forming such image may be varied at will is also disclosed.

Claims

1. An optical viewer having a plurality of light sources which are indipendently variable as to color and intensity, mounted in said optical viewer, a film-like transparency from about 50 to about 200 microns in thickness having a plurality of mutually exclusive areas, each individual area containing differently oriented spatial frequency carriers formed of a photopolymerized organic resin, said spatial frequency carriers having a spacing of from 200 to 2,000 lines per millimeter, and each of said light sources being positioned so as to cooperate with an individual area of said transparency whereby light from said light source is diffracted onto a display.

2. The transparency of claim 1 wherein the spatial frequency carriers have a spacing of from 500 to 750 lines per millimeter.