Back to results
US 4,068,922 AGranted
Front projection screen
AssigneeThe Singer Company
InventorMartin Dotsko
Life of this patent
Estimating the term…
Abstract
A cellulose acetate butyrate lacquer film containing minute beads of the clear lacquer is backed by a reflective surface, to form a high resolution front projection screen of selective gain. The gain of the screen depends upon the thickness of the lacquer film and the reflectivity of the backing member.
Claims8
A semi-specular front projection screen of selective gain comprising:
- a beaded film of cellulose acetate butyrate lacquer having a highly directional light scattering characteristic, said film comprising a plurality of spray coats of said lacquer with lacquer beads distributed throughout, said spray coats being derived from a spraying mixture formed by mixing 30 parts, by volume, of the following lacquer mixture:
- ______________________________________ Ingredient Parts by Weight ______________________________________ Ethyl Lactate 3.0 Paraplex G-40 1.0 Di-2 Ethylhexyl Phthalate (DOP) 1.0 Toluene 2.4 Ethyl Acetate 2.4 Acetone 7.6 ______________________________________
- ______________________________________ Ingredient Parts by Weight ______________________________________ Cellulose Acetate Butyrate EAB-381-1/2 1.0 Cellulose Acetate Butyrate EAB-381-20 1.2 ______________________________________
- with 80 parts by volume of the following diluent mixture:
- ______________________________________ Ingredient Parts by Weight ______________________________________ Toluene 5.6 Acetone 1.4 Ethyl Acetate 1.0;
- and ______________________________________
- a backing member having a light reflective surface adjacent said film, the thickness of the film and the degree of reflectivity of said surface being variable to control the gain of said screen.
4 more elements
A semi-specular front projection screen of selective gain comprising:
- a beaded film of cellulose acetate butyrate lacquer having a highly directional light scattering characteristic;
- a backing member having a light reflective surface adjacent said film, the thickness of the film and the degree of reflectivity of said surface being variable to control the gain of said screen;
- a layer of transparent plastic material sandwiched between said lacquer film and the reflective surface;
- and
- an optical grade cement affixing said plastic material to said reflective surface, said plastic material and cement having closely matching indices of refraction.
2 more elements
A method of constructing a semi-specular front projection screen of selective gain, comprising the steps of:
- forming a beaded film of cellulose acetate butyrate lacquer having a highly directional light scattering characteristic by overlaying spray coats of said lacquer, said spray coats being derived from a spraying mixture formed by mixing 30 parts, by volume, of the following lacquer mixture:
- ______________________________________ Ingredient Parts by Weight ______________________________________ Ethyl Lacetate 3.0 Paraplex G-40 1.0 Di-2-Ethylhexyl Phthalate (DOP) 1.0 Toluene 2.4 ______________________________________
- ______________________________________ Ingredient Parts by Weight ______________________________________ Ethyl Acetate 2.4 Acetone 7.6 Cellulose Acetate Butyrate EAB-381-1/2 1.0 Cellulose Acetate Butyrate EAB-381-20 1.2 ______________________________________
- with 80 parts by volume of the following diluent mixture:
- ______________________________________ Ingredient Parts by Weight ______________________________________ Toluene 5.6 Acetone 1.4 Ethyl Acetate 1.0 ______________________________________
- backing the lacquer film with a light reflective surface;
- and controlling the thickness of said film and degree of reflectivity of said surface to produce a desired screen gain.
4 more elements
Dependencies are inferred from the claim text.