Patent US3833285A successfully refreshed from Google Patents.
US3833285A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Retrodirective reflector visible over wide range of observation angles
Assignee: Stimsonite Corp
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Filing: 1973-05-22
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Granted: 1974-09-03
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Expires: 1993-05-22
Abstract
Abstract The reflector is constructed of transparent material and has a plurality of reflector elements at the rear and a light-receiving face at the front. Each reflector element has three faces intersecting at three edges, three dihedral angles being respectively defined by the intersection of adjacent faces. Two of the dihedral angles of all of the reflector elements are substantially 90*. The third dihedral angle of at least some of the reflector elements is substantially greater than the angle of the other two dihedral angles, so that light reflected by the reflector is diverged into an elongated pattern.
Inventors
- 👤 S Heenan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:44
CPC Classifications
G; G02; G02B; G02B5/00; G02B5/12; G02B5/122; G02B5/124
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
137 words
A retrodirective reflector for retrodirectively reflecting light in an elongated pattern, said reflector comprising a body of transparent material having a light-receiving front face, and a plurality of retrodirective reflector elements at the rear of said body, each of said reflector elements having first and second and third faces intersecting to form first and second and third dihedral angles, the edges respectively defined by said first dihedral angles lying in parallel first planes, said second and third dihedral angles of each reflector element being substantially 90*, said first dihedral angle of at least some of said reflector elements being substantially greater than the associated second and third dihedral angles, whereby the light reflected by said reflector is diverged to a greater extent in planes perpendicular to said first planes than in planes parallel to said first planes.
Claim 2
Dependent Claim
137 words
A retrodirective reflector for retrodirectively reflecting light in an elongated pattern, said reflector comprising a body of transparent material having a light-receiving front face, and a plurality of retrodirective reflector elements at the rear of said body, each of said reflector elements having first and second and third faces intersecting to form first and second and third dihedral angles, the edges respectively defined by said first dihedral angles lying in parallel first planes, said second and third dihedral angles of each reflector element being substantially 90*, said first dihedral angle of at least some of said reflector elements being substantially greater than the associated second and third dihedral angles, whereby the light reflected by said reflector is diverged to a greater extent in planes perpendicular to said first planes than in planes parallel to said first planes.
Claim 3
Dependent Claim
22 words
The retrodirective reflector set forth in claim 1, wherein said first dihedral angle of others of said reflector elements is substantially 90*.
Claim 4
Dependent Claim
21 words
The retrodirective reflector set forth in claim 1, wherein said first dihedral angle of said some reflector elements is about 90*30''.
Claim 5
Dependent Claim
46 words
The retrodirective reflector set forth in claim 1, wherein said first dihedral angle of said some reflector elements is such as to cause the light reflected thereby to have a peak specific intensity at an angle of about 1.3* in planes perpendicular to said first planes.
Claim 6
Dependent Claim
26 words
The retrodirective reflector set forth in claim 1, wherein said faces have cylindrical formations thereon to modify the amount of light spread furnished by said reflector.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-02 | 1978-03-04 | 1978-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-02 | 1982-03-04 | 1982-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-02 | 1986-03-04 | 1986-09-03 | $7700.00 | Window Closed / Lapsed |