US3861785A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wide angle mirror assembly
Assignee: CRYTON OPTICS Inc
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Filing: 1973-11-15
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Granted: 1975-01-21
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Expires: 1993-11-15
Abstract
Abstract A flat mirror assembly which incorporates a Fresnel lens and affords a wide angle view. The assembly is constituted by a Fresnel lens molded of plastic material and having a negative focal length, the lens being sandwiched between a rear plane mirror and a clear front pane, the sandwich being held within a frame.
Inventors
- 👤 Roberto Barbour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:22
CPC Classifications
B; B60; B60R; B60R1/00; B60R1/02; B60R1/08; B60R1/081; B60R1/082; G; G02; G02B; G02B5/00; G02B5/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
136 words
A wide-angle rear view mirror assembly comprising a flat, thin Fresnel lens having a negative focal length, said lens being constituted by a series of spaced prismatic grooves each at a different angle and at a different depth formed in a clear plastic sheet of high clarity, a plane mirror disposed behind said lens and a transparent plate disposed in front of said lens, said mirror and said plate being in direct contact with said flat lens to form a sandwich assembly, and a frame surrounding the margin of said sandwich assembly and protectively sealing said lens therein to prevent the entry of contaminants that would otherwise disturb the clarity of said lens, said lens having optical characteristics which in combination with said mirror are the equivalent of a convex mirror whose focal length is negative.
Claim 2
Dependent Claim
136 words
A wide-angle rear view mirror assembly comprising a flat, thin Fresnel lens having a negative focal length, said lens being constituted by a series of spaced prismatic grooves each at a different angle and at a different depth formed in a clear plastic sheet of high clarity, a plane mirror disposed behind said lens and a transparent plate disposed in front of said lens, said mirror and said plate being in direct contact with said flat lens to form a sandwich assembly, and a frame surrounding the margin of said sandwich assembly and protectively sealing said lens therein to prevent the entry of contaminants that would otherwise disturb the clarity of said lens, said lens having optical characteristics which in combination with said mirror are the equivalent of a convex mirror whose focal length is negative.
Claim 3
Dependent Claim
19 words
A wide angle assembly as set forth in claim 1, having a rectangular configuration to produce a panoramic view.
Claim 4
Dependent Claim
25 words
An assembly as set forth in claim 2, further including means to support said assembly in an automobile to provide a rear view mirror therefor.
Claim 5
Dependent Claim
28 words
An assembly as set forth in claim 1, wherein said lens is molded of plastic material and said plane mirror and said transparent plate are formed of glass.
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) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |