US3875453A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lamp with high color-discrimination capability
Assignee: Philips North America LLC
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Filing: 1973-08-10
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Granted: 1975-04-01
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Expires: 1993-08-10
Abstract
Abstract A lamp and method producing a generally purplish light having three constituent emissions in specific wavelength ranges. The light provides for optimum or near optimum color discrimination, and small color differences are 2 1/2 to 3 times more easily seen under this light than under daylight. The three emissions are located principally within the 400-470 nm, 500-550 nm and 610-680 nm wavelength ranges and the proportions are such that blending the three emissions produces visible light having, in ICI coordinates, an x in the range of about 0.27 to 0.45 and a y in the range of about 0.09 to 0.25.
Inventors
- 👤 Jr William A Thornton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:16
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
164 words
A device which efficiently generates light and illuminates objects in a manner which provides for substantially improved color discrimination, said device comprising: a. a three-component, light-generating medium forming an operative part of said device; b. means for energizing said medium to a visiblelight-generating condition; c. a first component of said medium, when energized, exhibiting a visible emission located principally in the 400-470 nm wavelength range; d. a second component of said medium, when energized exhibiting a visible emission located principally in the 500-550 nm wavelength range; e. a third component of said medium, when energized, exhibiting a visible emission located principally in the 610-680 nm wavelength range; and f. the relative proportions of said components of said light-generating medium being such that when their emissions are blended, there is produced visible light of predetermined x and y values of ICI coordinates, said x value being in the range of 0.27 to 0.45, and said y value being in the range of 0.09 to 0.25.
Claim 2
Independent Claim
164 words
A device which efficiently generates light and illuminates objects in a manner which provides for substantially improved color discrimination, said device comprising: a. a three-component, light-generating medium forming an operative part of said device; b. means for energizing said medium to a visiblelight-generating condition; c. a first component of said medium, when energized, exhibiting a visible emission located principally in the 400-470 nm wavelength range; d. a second component of said medium, when energized exhibiting a visible emission located principally in the 500-550 nm wavelength range; e. a third component of said medium, when energized, exhibiting a visible emission located principally in the 610-680 nm wavelength range; and f. the relative proportions of said components of said light-generating medium being such that when their emissions are blended, there is produced visible light of predetermined x and y values of ICI coordinates, said x value being in the range of 0.27 to 0.45, and said y value being in the range of 0.09 to 0.25.
Claim 3
Dependent Claim
58 words
The device of claim 1, wherein said emission of said first component of said medium is located substantially in the 400-435 nm wavelength range, said emission of said second component is located substantially in the 500-550 nm wavelength range, and said emission of said third component of said medium is located substantially in the 630-670 nm wavelength range.
Claim 4
Dependent Claim
12 words
The device of claim 1, wherein said device is a discharge lamp.
Claim 5
Dependent Claim
21 words
The device of claim 3, wherein said discharge lamp is a fluorescent lamp and said medium is a mixture of phosphors.
Claim 6
Dependent Claim
44 words
The device of claim 4, wherein said first component of said medium is strontium chloroapatite activated by divalent europium, said second component of said medium is zinc silicate activated by manganese, and said third component of said medium is magnesium fluorogermanate activated by manganese.
Claim 7
Dependent Claim
19 words
The device of claim 5, wherein said x value is about 0.32, and said y value is about 0.16.
Claim 8
Independent Claim
120 words
The method of efficiently generating light which provides substantially improved color discrimination for illuminated objects, which method comprises: a. blending together (1) a first light constituent having emission principally confined to the 400-470 nm wavelength range, (2) a second light constituent having an emission principally confined to the 500-550 nm wavelength range, and (3) a third light constituent having an emission principally confined to the 610-680 nm wavelength range; and b. controlling the relative light intensities of said first, second and third light constituents to produce visIble light of predetermined x and y values of ICI coordinates, said x value being in the range of 0.27 to 0.45, and said y value being in the range of 0.09 to 0.25.
Claim 9
Independent Claim
120 words
The method of efficiently generating light which provides substantially improved color discrimination for illuminated objects, which method comprises: a. blending together (1) a first light constituent having emission principally confined to the 400-470 nm wavelength range, (2) a second light constituent having an emission principally confined to the 500-550 nm wavelength range, and (3) a third light constituent having an emission principally confined to the 610-680 nm wavelength range; and b. controlling the relative light intensities of said first, second and third light constituents to produce visIble light of predetermined x and y values of ICI coordinates, said x value being in the range of 0.27 to 0.45, and said y value being in the range of 0.09 to 0.25.
References Cited (Backward Citations)
US2103038A
Cited
US3363134A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-31 | 1978-09-30 | 1979-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-31 | 1982-09-30 | 1983-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-31 | 1986-09-30 | 1987-04-01 | $7700.00 | Window Closed / Lapsed |