US4068922A — Front projection screen

Claim 1

Independent Claim 161 words

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.

Claim 2

Dependent Claim 161 words

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.

Claim 3

Dependent Claim 13 words

The screen of claim 1 wherein said backing member comprises an aluminum plate.

Claim 4

Dependent Claim 17 words

The screen of claim 1 wherein said backing member comprises a substrate with a reflective coating thereon.

Claim 5

Dependent Claim 22 words

The screen of claim 1 further including a layer of transparent plastic material sandwiched between said lacquer film and the reflective surface.

Claim 6

Dependent Claim 30 words

The screen of claim 4 further including an optical grade cement affixing said plastic material to said reflective surface, said plastic material and cement having closely matching indices of refraction.

Claim 7

Dependent Claim 33 words

The screen of claim 4 wherein said plastic material comprises a preformed sheet of plastic and said backing member comprises a coating of reflective material on the back surface of said plastic sheet.

Claim 8

Dependent Claim 96 words

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.

Claim 9

Dependent Claim 96 words

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.

Claim 10

Independent Claim 154 words

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.

Claim 11

Independent Claim 154 words

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.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1981-01-16	1981-07-18	1982-01-17	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1985-01-16	1985-07-18	1986-01-17	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1989-01-16	1989-07-18	1990-01-17	$7700.00	Window Closed / Lapsed

Front projection screen

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