US3963953A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Color mismatch accentuating device
Assignee: Philips North America LLC
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Filing: 1975-04-29
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Granted: 1976-06-15
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Expires: 1995-04-29
Abstract
Abstract A device to generate light of a quality which will accent the mismatch in color appearance of objects having different spectral reflectance curves but which appear at least generally similar in color and lightness under illumination by daylight. As there are many objects which match under one illuminant such as daylight, but do not match under other illuminants, there are many applications in which it is desirable to provide for early detection of potential mismatches. This invention generates visible radiation substantially confined to at least two of the 405-435 nm, 475-505 nm, 565-595 nm, and 645-675 nm wavelength ranges, and which preferably has less than 20 percent of the radiations in the 435-465 nm, 525-555 nm and 595-625 nm wavelength ranges.
Inventors
- 👤 William A. Thornton, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:04
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
120 words
A device which generates light of a quality which will accentuate the mismatch in color appearance of objects having different spectral reflectance curves but which appear at least generally similar in color under illumination by daylight, said device comprising: a. a light generating medium for generating visible radiations which are substantially confined to at least two of the four color mismatch accentuating wavelength ranges and which are not substantially confined to two complementary color wavelength ranges, said color-mismatch-accentuating wavelength ranges consisting of: i. from 405 to 435 nm, ii. from 475 to 505 nm, iii. from 565 to 595 nm, iv. from 645 to 675 nm; and b. means for energizing said light generating medium to a light generating condition.
Claim 2
Independent Claim
120 words
A device which generates light of a quality which will accentuate the mismatch in color appearance of objects having different spectral reflectance curves but which appear at least generally similar in color under illumination by daylight, said device comprising: a. a light generating medium for generating visible radiations which are substantially confined to at least two of the four color mismatch accentuating wavelength ranges and which are not substantially confined to two complementary color wavelength ranges, said color-mismatch-accentuating wavelength ranges consisting of: i. from 405 to 435 nm, ii. from 475 to 505 nm, iii. from 565 to 595 nm, iv. from 645 to 675 nm; and b. means for energizing said light generating medium to a light generating condition.
Claim 3
Dependent Claim
26 words
The device of claim 1, wherein less than 20 percent of the visible radiations are in the 435-465 nm, 525-555 nm, and 595-625 nm wavelength ranges.
Claim 4
Dependent Claim
20 words
The device of claim 2, wherein said radiations are substantially confined to two of said color mismatch accentuating wavelength ranges.
Claim 5
Dependent Claim
17 words
The device of claim 2, wherein radiations in all four of said color-mismatch-accentuating wavelength ranges are utilized.
Claim 6
Dependent Claim
18 words
The device of claim 2, wherein said radiations are substantially confined to three of said color-mismatch-accentuating wavelength ranges.
Claim 7
Dependent Claim
22 words
The device of claim 5, wherein said radiations are substantially confined to the 405-435 nm, 475-505 nm and 645-675 nm wavelength ranges.
References Cited (Backward Citations)
US3875453A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-15 | 1979-12-15 | 1980-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-15 | 1983-12-15 | 1984-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-15 | 1987-12-15 | 1988-06-15 | $7700.00 | Window Closed / Lapsed |