US3758770A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reflector having radial flutes
Assignee: US Philips Corp
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Filing: 1971-12-21
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Granted: 1973-09-11
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Expires: 1991-12-21
Abstract
Abstract A parabaloidal reflector adapted to receive an elongate light source along the axis of the reflector includes a number of fluted portions arranged in a repeated pattern over the surface of the reflector. The reflector achieves more uniform light reflection because adjacent fluted portions are concave or convex when viewed in cross-section and which merge in a geometrically discontinuous manner. The radius of curvature of the fluted portions in cross-section is the same from the widened open portion of the reflector to the narrowed tip.
Inventors
- 👤 W Morasz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 04:28
CPC Classifications
F; F21; F21V; F21V7/00; F21V7/04; F21V7/09
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
290 words
A reflector for an elongate light source comprising: a contoured element being shaped in the form of a parabaloid having a closed tip portion at one end and a widened open portion at the other end, said element having a reflecting inner surface comprising a number of light-spreading flutes which extend along the radial contours of the element from the tip portion to the open portion, said flutes including convex and concave portions relative to the inner surface of the reflector, said convex and concave portions being arranged in a repeating pattern, adjacent flute portions merging in a geometrically discontinuous manner when viewed in crosssection, each convex flute portion having side edges where joined with adjacent flute portions and having a light spreading capacity which, when calculated in a direction at right angles to the axis of the parabaloidal reflector, decreases from a maximum in the proximity of the side edges of the convex flute portion to a minimum at a location between the two edges, each concave flute portion having side edges where joined with adjacent flute portions and having a light spreading capacity which, when calculated in a direction at right angles to the axis of the parabaloidal reflector, increases from a minimum in the proximity of the edges of the flute to a maximum at a location between the edges, the maximum light spreading capacity of the convex flute portions decreasing in a direction from the widened portion of the reflector toward the tip of the reflector, the minimum spreading capacity of the concave flute portions increasing in the direction from the tip to the widened open portion, said reflector adapted to receive an elongate light source arranged in the reflector along the axis of the parabaloid.
Claim 2
Dependent Claim
290 words
A reflector for an elongate light source comprising: a contoured element being shaped in the form of a parabaloid having a closed tip portion at one end and a widened open portion at the other end, said element having a reflecting inner surface comprising a number of light-spreading flutes which extend along the radial contours of the element from the tip portion to the open portion, said flutes including convex and concave portions relative to the inner surface of the reflector, said convex and concave portions being arranged in a repeating pattern, adjacent flute portions merging in a geometrically discontinuous manner when viewed in crosssection, each convex flute portion having side edges where joined with adjacent flute portions and having a light spreading capacity which, when calculated in a direction at right angles to the axis of the parabaloidal reflector, decreases from a maximum in the proximity of the side edges of the convex flute portion to a minimum at a location between the two edges, each concave flute portion having side edges where joined with adjacent flute portions and having a light spreading capacity which, when calculated in a direction at right angles to the axis of the parabaloidal reflector, increases from a minimum in the proximity of the edges of the flute to a maximum at a location between the edges, the maximum light spreading capacity of the convex flute portions decreasing in a direction from the widened portion of the reflector toward the tip of the reflector, the minimum spreading capacity of the concave flute portions increasing in the direction from the tip to the widened open portion, said reflector adapted to receive an elongate light source arranged in the reflector along the axis of the parabaloid.
Claim 3
Dependent Claim
44 words
A reflector as in claim 1 wherein each convex flute portion is cojoined with a concave flute portion on either side edge and each concave portion is cojoined with a convex portion at one side edge and a concave portion at the other edge.
Claim 4
Dependent Claim
37 words
A reflector as claimed in claim 1 wherein each flute portion has the same radius of curvature when viewed in cross-section to the parabaloidal radius dimension of the flute portion at any place along the flute portion.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |