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US3575499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Previewing apparatus
Assignee: Rollei of America Inc
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Filing: 1968-09-13
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Granted: 1971-04-20
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Expires: 1988-09-13
Abstract
Abstract A light-transmitting apparatus for a projector to improve the resolution and color of a transparency being focused on a previewing screen wherein an inner spherical wall portion that terminates at its open end in four concave edge portions that form a square is employed as a reflector to reflect a cone of light rays from a light source into a square beam of light rays for passage through a light-diffusing plate and the transparency that are both of substantially the same size as the square beam so that only uniform rays of light that are carrying black, color, or clear portions of the transparency can be focused by means of an inexpensive lens and light stop onto the screen.
Inventors
- 👤 John P Mahoney Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:58
CPC Classifications
G; G03; G03B; G03B23/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
213 words
A light-transmitting apparatus for a projector to improve the resolution and color of a transparency that is projected on a screen, comprising a light source, a diffusing means, a reflector constructed to receive a cone of light rays from the light source and to reflect a preselected resulting square beam of light rays therefrom through the diffusing means and the transparency, the said reflector being of a preselected size to emit a square beam of light that is of the same area as the diffusing means and transparency and which will thereby remain within the confines of the diffusing means and the transparency and wherein the reflector is of a spherical-shaped configuration and terminates at its open end in edge portions that form a square, and wherein the reflector is constructed of a polished metal surface formed from a wall portion of a hollow sphere, the light source is operably positioned to provide additional rays of light for other optical parts to simultaneously pass light through a second transparency that is in a show position in the projector onto a second screen, to simultaneously reflect still other rays of light from said common light source in series against other reflectors and the second transparency onto a photosensitive surface of an automatic focusing circuit.
Claim 2
Dependent Claim
213 words
A light-transmitting apparatus for a projector to improve the resolution and color of a transparency that is projected on a screen, comprising a light source, a diffusing means, a reflector constructed to receive a cone of light rays from the light source and to reflect a preselected resulting square beam of light rays therefrom through the diffusing means and the transparency, the said reflector being of a preselected size to emit a square beam of light that is of the same area as the diffusing means and transparency and which will thereby remain within the confines of the diffusing means and the transparency and wherein the reflector is of a spherical-shaped configuration and terminates at its open end in edge portions that form a square, and wherein the reflector is constructed of a polished metal surface formed from a wall portion of a hollow sphere, the light source is operably positioned to provide additional rays of light for other optical parts to simultaneously pass light through a second transparency that is in a show position in the projector onto a second screen, to simultaneously reflect still other rays of light from said common light source in series against other reflectors and the second transparency onto a photosensitive surface of an automatic focusing circuit.
Claim 3
Dependent Claim
213 words
A light-transmitting apparatus for a projector to improve the resolution and color of a transparency that is projected on a screen, comprising a light source, a diffusing means, a reflector constructed to receive a cone of light rays from the light source and to reflect a preselected resulting square beam of light rays therefrom through the diffusing means and the transparency, the said reflector being of a preselected size to emit a square beam of light that is of the same area as the diffusing means and transparency and which will thereby remain within the confines of the diffusing means and the transparency and wherein the reflector is of a spherical-shaped configuration and terminates at its open end in edge portions that form a square, and wherein the diffusing means is constructed of a plate-shaped configuration that is immediately adjacent said transparency, said diffused light passing through the transparency is focused by way of a lens and optical stop against a secondary reflector onto the screen, and wherein the light source, reflector, diffusing means, single lens and optical stop are fixedly connected to a chassis located within a slide projector and said screen is formed in the casing of the projector for previewing a slide before it is moved to a projecting position.
Claim 4
Dependent Claim
213 words
A light-transmitting apparatus for a projector to improve the resolution and color of a transparency that is projected on a screen, comprising a light source, a diffusing means, a reflector constructed to receive a cone of light rays from the light source and to reflect a preselected resulting square beam of light rays therefrom through the diffusing means and the transparency, the said reflector being of a preselected size to emit a square beam of light that is of the same area as the diffusing means and transparency and which will thereby remain within the confines of the diffusing means and the transparency and wherein the reflector is of a spherical-shaped configuration and terminates at its open end in edge portions that form a square, and wherein the diffusing means is constructed of a plate-shaped configuration that is immediately adjacent said transparency, said diffused light passing through the transparency is focused by way of a lens and optical stop against a secondary reflector onto the screen, and wherein the light source, reflector, diffusing means, single lens and optical stop are fixedly connected to a chassis located within a slide projector and said screen is formed in the casing of the projector for previewing a slide before it is moved to a projecting position.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |