Patent EP0248974A2 successfully refreshed from Google Patents.
EP0248974A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Color wheel assembly for lighting equipment
Assignee: Vari Lite Inc
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Filing: 1987-01-24
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Granted: —
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Expires: 2007-01-24
Abstract
Abstract A lighting fixture includes a source for producing a beam of light and pair of color wheels. Each of the color wheels has a plurality of dichoric filters mounted on the periphery of the wheel with the filters positioned contiguous to each other. The light beam is directed to a focal point. Each of the color wheels can be rotated to place the peripheral dichroic filters in position to intercept the beam. One of the color wheels is equipped with long wave pass dichroic filters while the other color wheel is equipped with short wave pass dichroic filters. By aligning various combinations of these filters, a large number of different colors with different saturations can be produced. The cutoff wavelengths for the dichoric filters are selected to be different at the long and short wavelengths of the filter set, such that there is produced a perceived uniform graduation of colors across the spectrum. Each of the dichroic filters mounted on the color wheels is in a shape of a trapezoid and is mounted adjacent other filters, such that there is no blanking of light or leakage of light in the process of changing from one filter to the next.
Inventors
- 👤 James M. Bornhorst
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 19:24
CPC Classifications
F; F21; F21S; F21S10/00; F21S10/02; F21S10/007; F21V; F21V9/00; F21V9/40; F21V9/45; F21W; F21W2131/00; F21W2131/40; F21W2131/406
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
244 words
A lighting instrument for producing a plurality of colors of light from a light source which produces a light beam, comprising: a first rotatable color wheel comprising a first set of dichroic filters mounted about the periphery of a hub wherein each of said filters in said first set can be selectively positioned in said light beam by rotation of said first color wheel, said first set of dichroic filters comprising long wave pass filters each of which transmits light having a wavelength greater than a cutoff wavelength of the filter, the cutoff wavelengths of said first set of filters spaced in the visible spectrum at respective intervals, said intervals being greater at longer wavelengths than at shorter wavelengths, a second rotatable color wheel'comprising a second set of dichpric filters mounted about the periphery of a hub wherein each of said filters in said second set can be selectively positioned in said light beam by rotation of said second color wheel, wherein said filters are positioned such that said light beam can pass sequentially through one filter in said first set and one filter in said second set, and said second set of dichroic filters comprising short wave pass filters each of which transmits light having a wavelength less than a cutoff wavelength of the filter, the cutoff wavelengths of said second set of filters spaced in the visible spectrum at respective intervals, said intervals being greater at shorter wavelengths than at longer wavelengths.
Claim 2
Dependent Claim
244 words
A lighting instrument for producing a plurality of colors of light from a light source which produces a light beam, comprising: a first rotatable color wheel comprising a first set of dichroic filters mounted about the periphery of a hub wherein each of said filters in said first set can be selectively positioned in said light beam by rotation of said first color wheel, said first set of dichroic filters comprising long wave pass filters each of which transmits light having a wavelength greater than a cutoff wavelength of the filter, the cutoff wavelengths of said first set of filters spaced in the visible spectrum at respective intervals, said intervals being greater at longer wavelengths than at shorter wavelengths, a second rotatable color wheel'comprising a second set of dichpric filters mounted about the periphery of a hub wherein each of said filters in said second set can be selectively positioned in said light beam by rotation of said second color wheel, wherein said filters are positioned such that said light beam can pass sequentially through one filter in said first set and one filter in said second set, and said second set of dichroic filters comprising short wave pass filters each of which transmits light having a wavelength less than a cutoff wavelength of the filter, the cutoff wavelengths of said second set of filters spaced in the visible spectrum at respective intervals, said intervals being greater at shorter wavelengths than at longer wavelengths.
Claim 3
Dependent Claim
41 words
A lighting instrument as recited in Claim 1 wherein each of said filters is joined along one edge thereof to the periphery of the respective one of said hubs wherein each of said filters is directed outward from the respective hub.
Claim 4
Dependent Claim
27 words
A lighting instrument as recited in Claim 1 wherein each of a plurality of said filters is positioned contiguous to others of said filters in said set.
Claim 5
Dependent Claim
31 words
A lighting instrument as recited in Claim 1 wherein each of said filters has a trapezoidal shape and only one edge of each said filter is connected to the respective hub.
Claim 6
Dependent Claim
26 words
A lighting instrument as recited in Claim 1 wherein the filters in each of said sets comprise a substantially closed annular ring about the respective hub.
Claim 7
Dependent Claim
33 words
A lighting instrument as recited in Claim 1 wherein the filters in each of said sets are arranged about the respective hubs in an order from lighter color shades to darker color shades.
Claim 8
Dependent Claim
20 words
A lighting instrument as recited in Claim 1 wherein each of said filters has a shape with all sides linear.
Claim 9
Dependent Claim
41 words
A lighting instrument as recited in Claim 1 wherein each of said hubs comprises first and second plates having different diameters and coaxially joined together to form a step on the periphery of the hub, said step for receiving said filters.
Claim 10
Dependent Claim
23 words
A lighting instrument as recited in Claim 1 wherein each of said filters is banded to the respective hub by a resilient adhesive.
Claim 11
Dependent Claim
49 words
A color wheel for use in a lighting instrument for producing multiple colors of light, comprising: a hub rotatable about the axis thereof, and a set of planar dichroic filters, each filter joined along one edge thereof to the periphery of said hub and extending outward from said hub.
Claim 12
Dependent Claim
49 words
A color wheel for use in a lighting instrument for producing multiple colors of light, comprising: a hub rotatable about the axis thereof, and a set of planar dichroic filters, each filter joined along one edge thereof to the periphery of said hub and extending outward from said hub.
Claim 13
Dependent Claim
27 words
A color wheel as recited in Claim 10 wherein each of a plurality of said filters is positioned between and contiguous to other filters in said set.
Claim 14
Dependent Claim
20 words
A color wheel as recited in Claim 10 wherein said filters form a substantially closed annular ring encircling said hub.
Claim 15
Dependent Claim
20 words
A color wheel as recited in Claim 10 wherein each of said filters has a shape with all sides linear.
Claim 16
Dependent Claim
17 words
A color wheel as recited in Claim 10 wherein each of said filters has a trapezoidal shape.
Claim 17
Dependent Claim
37 words
15 A color wheel as recited in Claim 10 wherein said hub comprises first and second plates having different diameters and coaxially joined together to form a step on the hub, said step for receiving said filters.
Claim 18
Dependent Claim
23 words
A color wheel as recited in Claim 10 wherein each of said filters is bonded to said hub by a resilient adhesive. 0
Claim 19
Dependent Claim
33 words
A filter for coloring a light beam comprising a planar glass plate having deposited layers thereon for selectively passing and reflecting spectral portions of said light beam, said plate having a trapezoidal configuration.
Claim 20
Dependent Claim
33 words
A filter for coloring a light beam comprising a planar glass plate having deposited layers thereon for selectively passing and reflecting spectral portions of said light beam, said plate having a trapezoidal configuration.
Claim 21
Dependent Claim
18 words
A filter as recited in Claim 17 wherein the nonparallel sides of said filter are of equal length.
Claim 22
Dependent Claim
16 words
A filter as recited in Claim 17 wherein said filter is symmetrical about a center axis.
References Cited (Backward Citations)
No citation records indexed.
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