Patent US4468092A successfully refreshed from Google Patents.
US4468092A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rear projection screen
Assignee: Mitsubishi Chemical Corp
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Filing: 1983-02-18
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Granted: 1984-08-28
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Expires: 2003-02-18
Abstract
Abstract A rear projection screen suitable for use as, for example, a screen for video projector. The rear projection screen is provided with a lenticulated surface at least one the viewer's side thereof. The lenticulated surface is constituted by a plurality of lenticule units each having total reflection surfaces on both inclined flanks thereof and a plurality of curved surface portions between both inclined flanks. The arrangement is such that a part of the light rays impinging from the projection side of the screen are reflected by the total reflection surfaces and then pass through the curved surface portions of each lenticule unit. Another type of lens may be formed between each of the adjacent lenticule units.
Inventors
- 👤 Masao Inoue
- 👤 Shingo Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:03
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/54; G03B21/56; G03B21/60; G03B21/62; G03B21/625
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
145 words
A rear projection screen having front and rear surfaces and a light transmitting medium therebetween, the screen being adapted to receive light rays at the rear surface and transmit the rays through the medium and cause them to emanate from the front surface, the front surface being formed with a plurality of parallel lenticule units arranged to disperse emanating light rays over a wide angle, each lenticule unit being formed with a pair of flanks and with a crest having only two curved surfaces, one adjacent to each flank, each flank having a portion extending toward the rear surface of the screen which forms an angle greater than the critical angle to the plane of the rear surface so as to provide a total reflection surface to reflect transmitted rays incident on that flank portion and cause them to emanate through the adjacent curved surface.
Claim 2
Dependent Claim
145 words
A rear projection screen having front and rear surfaces and a light transmitting medium therebetween, the screen being adapted to receive light rays at the rear surface and transmit the rays through the medium and cause them to emanate from the front surface, the front surface being formed with a plurality of parallel lenticule units arranged to disperse emanating light rays over a wide angle, each lenticule unit being formed with a pair of flanks and with a crest having only two curved surfaces, one adjacent to each flank, each flank having a portion extending toward the rear surface of the screen which forms an angle greater than the critical angle to the plane of the rear surface so as to provide a total reflection surface to reflect transmitted rays incident on that flank portion and cause them to emanate through the adjacent curved surface.
Claim 3
Dependent Claim
29 words
A rear projection screen according to claim 1 wherein the sum of the pitches of the curved surfaces is at least 40% of the pitch of the lenticule unit.
Claim 4
Dependent Claim
31 words
A rear projection screen according to claim 2 wherein the sum of the pitches of the curved surfaces is between about 40% and 70% of the pitch of the lenticule unit.
Claim 5
Dependent Claim
17 words
A rear projection screen according to claim 1 wherein the total reflection surface includes a curved surface.
Claim 6
Dependent Claim
23 words
A rear projection screen according to claim 1 wherein a Fresnel lens is formed on the rear surface of said rear projection screen.
Claim 7
Dependent Claim
19 words
A projection screen according to claim 1 wherein a light diffusing material is admixed in the light transmitting medium.
Claim 8
Dependent Claim
22 words
A rear projection screen according to claim 1 wherein at least one of the front and rear surfaces is a mat surface.
Claim 9
Dependent Claim
19 words
A rear projection screen according to claim 1 including an external light absorption layer on the total reflection surface.
Claim 10
Dependent Claim
24 words
A rear projection screen according to claim 8 including a light reflection layer between the external light absorption layer and the total reflection surface.
Claim 11
Dependent Claim
190 words
A rear projection screen having front and rear surfaces and a light transmitting medium therebetween, the screen being adapted to receive light rays at the rear surface and transmit the rays through the medium and cause them to emanate from the front surface, the front surface being formed with a plurality of parallel lenticule units arranged to disperse the emanating light rays over a wide angle, each lenticule unit being formed with a pair of flanks and with a crest having at least one curved surface adjacent to each flank, each flank having a portion extending toward the rear surface of the screen which forms an angle greater than the critical angle to the plane of the rear surface so as to provide a total reflection surface to reflect transmitted rays incident on that flank portion and cause them to emanate through the adjacent curved surface, the curved surfaces adjacent to the flanks being arranged to transmit light received directly from the rear surface of the screen and disperse it through one angular field and to transmit light reflected from the adjacent flank and disperse it through another angular field.
Claim 12
Dependent Claim
190 words
A rear projection screen having front and rear surfaces and a light transmitting medium therebetween, the screen being adapted to receive light rays at the rear surface and transmit the rays through the medium and cause them to emanate from the front surface, the front surface being formed with a plurality of parallel lenticule units arranged to disperse the emanating light rays over a wide angle, each lenticule unit being formed with a pair of flanks and with a crest having at least one curved surface adjacent to each flank, each flank having a portion extending toward the rear surface of the screen which forms an angle greater than the critical angle to the plane of the rear surface so as to provide a total reflection surface to reflect transmitted rays incident on that flank portion and cause them to emanate through the adjacent curved surface, the curved surfaces adjacent to the flanks being arranged to transmit light received directly from the rear surface of the screen and disperse it through one angular field and to transmit light reflected from the adjacent flank and disperse it through another angular field.
Claim 13
Dependent Claim
24 words
A rear projection screen according to claim 10 wherein the crest includes a convex lens portion between the curved surfaces adjacent to the flanks.
Claim 14
Dependent Claim
25 words
A rear projection screen according to claim 11 wherein the surface of the convex lens portion has the shape of an arc of a circle.
Claim 15
Dependent Claim
17 words
A rear projection screen according to claim 10 wherein the total reflection surface includes a curved surface.
Claim 16
Dependent Claim
23 words
A rear projection screen according to claim 10 wherein a Fresnel lens is formed on the rear surface of said rear projection screen.
Claim 17
Dependent Claim
20 words
A rear projection screen according to claim 10 wherein a light diffusing material is admixed in the light transmitting medium.
Claim 18
Dependent Claim
22 words
A rear projection screen according to claim 10 wherein at least one of the front and rear surfaces is a mat surface.
Claim 19
Dependent Claim
22 words
A rear projection screen according to claim 10 including a further convex lens portion formed between each adjacent pair of lenticule units.
Claim 20
Dependent Claim
19 words
A rear projection screen according to claim 10 including an external light absorption layer on the total reflection surface.
Claim 21
Dependent Claim
24 words
A rear projection screen according to claim 18 including a light reflection layer between the external light absorption layer and the total reflection surface.
Claim 22
Dependent Claim
157 words
A rear projection screen having front and rear surfaces and a light transmitting medium therebetween, the screen being adapted to receive light rays at the rear surface and transmit the rays through the medium and cause them to emanate from the front surface, the front surface being formed with a plurality of parallel lenticule units arranged to disperse emanating light rays over a wide angle, each lenticule unit being formed with a pair of flanks and with a crest having at least one curved surface adjacent to each flank, each flank having a portion extending toward the rear surface of the screen which forms an angle greater than the critical angle to the plane of the rear surface so as to provide a total reflection surface to reflect transmitted rays incident on that flank portion and cause them to emanate through the adjacent curved surface, and a light absorbing layer coated on the surface of each flank.
Claim 23
Dependent Claim
157 words
A rear projection screen having front and rear surfaces and a light transmitting medium therebetween, the screen being adapted to receive light rays at the rear surface and transmit the rays through the medium and cause them to emanate from the front surface, the front surface being formed with a plurality of parallel lenticule units arranged to disperse emanating light rays over a wide angle, each lenticule unit being formed with a pair of flanks and with a crest having at least one curved surface adjacent to each flank, each flank having a portion extending toward the rear surface of the screen which forms an angle greater than the critical angle to the plane of the rear surface so as to provide a total reflection surface to reflect transmitted rays incident on that flank portion and cause them to emanate through the adjacent curved surface, and a light absorbing layer coated on the surface of each flank.
Claim 24
Dependent Claim
24 words
A rear projection screen according to claim 20 including a light reflection layer between the external light absorption layer and the total reflection surface.
References Cited (Backward Citations)
CH98590A
Cited
US2510344A
Cited
US2529701A
Cited
AT180418B
Cited
US2738706A
Cited
US2870673A
Cited
US3218924A
Cited
US3257900A
Cited
US3279314A
Cited
US3578841A
Cited
US3830556A
Cited
EP0037739A1
Cited
US4379617A
Cited
US4418986A
Cited
US4469402A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-28 | 1988-02-27 | 1988-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-28 | 1992-02-27 | 1992-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-28 | 1996-02-27 | 1996-08-28 | $7700.00 | Window Closed / Lapsed |