Patent US2148960A successfully refreshed from Google Patents.
Patent US4726134A successfully refreshed from Google Patents.
US4726134A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Roadway sign
Assignee: 3M Co
•
Filing: 1986-11-21
•
Granted: 1988-02-23
•
Expires: 2006-11-21
Abstract
Abstract An improved roadway sign comprising a light retroreflective indicia region and colored retroreflective background region is provided. The retroreflective properties of the regions are selected such that the ratio of the retroreflective brightness of the indicia to that of the background is substantially larger at observation locations within the legibility zone for the sign, than the ratio is at observation locations outside the legibility zone. The sign is conspicuous by virtue of the bright retroreflection and distinctive color of the background outside the legibility zone, yet is legible because of the increased contrast ratio of the indicia to the background in the legibility zone.
Inventors
- 👤 Henry L. Woltman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:25
CPC Classifications
E; E01; E01F; E01F9/00; G; G09; G09F; G09F13/00; G09F13/16; G09F13/04; G09F13/0418; G09F13/0472
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
60 words
A sign comprising a retroreflective background region and a retroreflective indicia region, wherein the retroreflective properties of said regions are selected such that the ratio of retroreflective brightness of said indicia to the retroreflective brightness of said background is substantially larger at locations within the legibility zone for the sign, than said ratio is at locations outside the legibility zone.
Claim 2
Dependent Claim
60 words
A sign comprising a retroreflective background region and a retroreflective indicia region, wherein the retroreflective properties of said regions are selected such that the ratio of retroreflective brightness of said indicia to the retroreflective brightness of said background is substantially larger at locations within the legibility zone for the sign, than said ratio is at locations outside the legibility zone.
Claim 3
Dependent Claim
19 words
The sign of claim 1 wherein said ratio at observation locations within the legibility zone is at least 6:1.
Claim 4
Dependent Claim
12 words
The sign of claim 2 wherein said ratio is at least 16:1.
Claim 5
Dependent Claim
15 words
The sign of claim 1 wherein said indicia region is covered by microlens-based retroreflective sheeting.
Claim 6
Dependent Claim
15 words
The sign of claim 4 wherein said background region is covered by cube-corner-based retroreflective sheeting.
Claim 7
Dependent Claim
15 words
The sign of claim 1 wherein said background region is covered by cube-corner-based retroreflective sheeting.
Claim 8
Dependent Claim
15 words
The sign of claim 6 wherein said indicia region is covered by cube-corner-based retroreflective sheeting.
Claim 9
Dependent Claim
15 words
The sign of claim 1 wherein said indicia comprise retroreflective sheeting adhered over said background.
Claim 10
Dependent Claim
62 words
A sign comprising a retroreflective background region and a retroreflective indicia region, wherein the retroreflective properties of said regions are selected such that the ratio of retroreflective brightness of said indicia to the retroreflective brightness of said background is at least 10:1 at an observation angle of 0.5°, and said ratio is less than about 6:1 at an observation angle of 0.1°.
Claim 11
Dependent Claim
62 words
A sign comprising a retroreflective background region and a retroreflective indicia region, wherein the retroreflective properties of said regions are selected such that the ratio of retroreflective brightness of said indicia to the retroreflective brightness of said background is at least 10:1 at an observation angle of 0.5°, and said ratio is less than about 6:1 at an observation angle of 0.1°.
References Cited (Backward Citations)
US285270A
Cited
US1751984A
Cited
US2022639A
Cited
US2043414A
Cited
US2326634A
Cited
US2910792A
Cited
US3712706A
Cited
US4215501A
Cited
US4588258A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |