Patent US4816975A successfully refreshed from Google Patents.
US4816975A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photography light
Assignee: Arriflex Corp
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Filing: 1987-07-02
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Granted: 1989-03-28
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Expires: 2007-07-02
Abstract
Abstract A light fixture for providing a cool uniform illumination into a photography field which is adjustable in intensity while maintaining a uniform color temperature. The light fixture includes a light source, an adjustable shutter for adjusting the amount of light passing therethrough, a reflector mirror having a dichroic heat coating thereon for reflecting the light from the shutter while passing any heat contained therein, and a round reflector for receiving the light from the reflector mirror through an end face and for dispersing the light through the circumference thereof by internal reflectance.
Inventors
- 👤 Volker W. Bahnemann
- 👤 Stanislaw Loth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 02:01
CPC Classifications
G; G03; G03B; G03B15/00; G03B15/02; G03B15/06; F; F21; F21W; F21W2131/00; F21W2131/40; F21W2131/406
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
151 words
A light fixture comprising: a light source; a shutter having an adjustable opening therein for allowing an adjustable amount of light from the light source to pass therethrough; a reflector mirror positioned in front of said shutter for reflecting the light emerging therefrom, said mirror including a dichroic heat coating for allowing any heat in said light to pass therethrough; and a round reflector for receiving the light reflected by said reflector mirror and comprising a polished clear rod having an axial ground slot formed therein, said rod having a light entrance face receiving the reflected light and a mirror coating on an end opposite to said entrance face, whereby said reflected light is internally reflected in said round reflector and illuminates the axial ground slot therein, light from the ground slot then exiting from said round reflector, the surface thereof focusing the exiting light at a short focal length distance.
Claim 2
Dependent Claim
151 words
A light fixture comprising: a light source; a shutter having an adjustable opening therein for allowing an adjustable amount of light from the light source to pass therethrough; a reflector mirror positioned in front of said shutter for reflecting the light emerging therefrom, said mirror including a dichroic heat coating for allowing any heat in said light to pass therethrough; and a round reflector for receiving the light reflected by said reflector mirror and comprising a polished clear rod having an axial ground slot formed therein, said rod having a light entrance face receiving the reflected light and a mirror coating on an end opposite to said entrance face, whereby said reflected light is internally reflected in said round reflector and illuminates the axial ground slot therein, light from the ground slot then exiting from said round reflector, the surface thereof focusing the exiting light at a short focal length distance.
Claim 3
Dependent Claim
15 words
A light fixture as claimed in claim 1, wherein said polished clear rod is acrylic.
Claim 4
Dependent Claim
15 words
A light fixture as claimed in claim 1, wherein said polished clear rod is glass.
Claim 5
Dependent Claim
38 words
A light fixture as claimed in claim 1, wherein said light fixture further includes a housing surrounding said light source, said shutter and said reflector mirror, said housing preventing stray light from being emitted by said light fixture.
Claim 6
Dependent Claim
55 words
A light fixture as claimed in claim 4, wherein said light fixture further includes a spherical reflector surrounding a rear half of said round reflector defined by said axial ground slot, whereby light exiting from this rear half is reflected by said spherical reflector both back into the ground reflector and into a photography field.
References Cited (Backward Citations)
US4233650A
Cited
US4561043A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-03-27 | 1992-09-26 | 1993-03-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-27 | 1996-09-26 | 1997-03-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-27 | 2000-09-26 | 2001-03-28 | $7700.00 | Window Closed / Lapsed |