US4969075A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-glare light
Assignee: Steelcase Development Inc
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Filing: 1989-05-05
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Granted: 1990-11-06
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Expires: 2009-05-05
Abstract
Abstract A low-glare light having a light source behind a transparent sheet of dielectric material. The transparent sheet has a prismatic surface on one side containing a plurality of elongated prisms and a plano surface on the opposite side. The transparent sheet is positioned with the prismatic surface facing the source of light with the elongated prisms perpendicular to the source of light.
Inventors
- 👤 Randall S. Helm
- 👤 Richard A. Benoit
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:39
CPC Classifications
F; F21; F21V; F21V5/00; F21V5/02; F21S; F21S8/00; F21S8/04; F21W; F21W2131/00; F21W2131/40; F21W2131/402; F21Y; F21Y2103/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
113 words
A low-glare task light comprising: a housing for supporting the light and for protecting it from dust and dirt; a socket for a light source disposed in said housing; a diffuser for evenly spreading the light coming from the housing over a workspace, said diffuser comprising a sheet of prismatic material having a pattern of elongated contiguous prism-like grooves on one surface and plane opposite surface, said prismatic material being positioned in the housing with the grooves facing the source of light in said housing and with the grooves positioned relative to the source of light to that angle which produces optimum diffusion and minimum bright spots on a workspace to be illuminated.
Claim 2
Dependent Claim
113 words
A low-glare task light comprising: a housing for supporting the light and for protecting it from dust and dirt; a socket for a light source disposed in said housing; a diffuser for evenly spreading the light coming from the housing over a workspace, said diffuser comprising a sheet of prismatic material having a pattern of elongated contiguous prism-like grooves on one surface and plane opposite surface, said prismatic material being positioned in the housing with the grooves facing the source of light in said housing and with the grooves positioned relative to the source of light to that angle which produces optimum diffusion and minimum bright spots on a workspace to be illuminated.
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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) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |