Symmetrical color changer system

• US 4,958,265 A
• Filed: 08/15/1989
• Issued: 09/18/1990
• Est. Priority Date: 03/04/1988
• Status: Expired due to Fees

• Current Assignee: Altman Stage Lighting Company Incorporated
• Original Assignee: Altman Stage Lighting Company Incorporated
• Inventors: Solomon, Dennis
• Primary Examiner(s): Husar, Stephen F.
• Application Number:
  US07/393,979
• Time in Patent Office: 399 Days
• Field of Search: 350/313, 350/315, 362/16, 362/18, 362/293
• US Class Current: 362/293
• CPC Class Codes: F21S 10/02 changing colors F21S10/002 - F21S10/007, F21S10/04 take precedence
• CPC Class Codes: F21V 9/40 with provision for controlling spectral properties, e.g. colour, or intensity
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios

Abstract

A color changer system including a pair of slidable color filter plates or a pair of rotatable color filter disks positioned on opposed side of a beam aperture through which a beam of white light passes. The pair of filter plates or filter disks are simultaneously movable or rotatable, respectively, across the beam aperture orthogonal to the beam axis so as to enhance a particular color. The movement of the filter plates or disks are movable into the beam symmetrical to the center of the beam aperture so that distribution of color saturation of the beam is symmetrical about the center of the beam aperture during movement of said first and second color filter means. Progressive variable filtering regions defining a plurality of color enhancing capacities either included diffused color filtering material or dichroic color filtering material. When the dichroic color filtering material is used, alternating clear and dichroic filtering strips are located in each filtering region. When the pair filter plates or filter disks overlap, the clear and dichroic filtering strips of each pair complement so that the lightwaves of the beam are filtered through only one of the pair of plates or strips.

Claims

1. A color changer system including a source of white light forming a light beam having a beam axis of propogation and a beam aperture through which the light beam passes, the beam aperture having a center coextensive with the axis of propagation, comprising, in combination,

oppositely disposed color filter means positioned adjacent to the beam aperture,

said oppositely disposed color filter means including first color filter means positioned adjacent to the beam aperture and second color filter means positioned adjacent to the beam aperture in substantially the same plane as that of said first color filter means, said first and second color filter means being simultaneously movable across the beam aperture orthogonal to the beam aperture and being adapted to meet in a mid position relative to the center of said beam aperture,

said first and second color filter means further including a plurality of progressive variable filter regions ranging as percents of color filtering capacity relative to a particular color and ranging between 10% and 50% in 10% incremental ranges, each large enough in area to cover the beam aperture area, and the color densities of each filtering region differing from one another but being evenly distributed throughout each filtering region;

wherein selected lightwaves are deleted in predetermined amounts in accordance with the positions of said first and second color filter means across said beam aperture so as to enhance said particular color contained in said light beam; and

said first and second color filter means being simultaneously movable into the light beam symmetrical to the beam axis of propagation so that distribution of color saturation of the light beam is symmetrical about the center of the beam aperture during movement of said first and second color filter means, whereby a generally even level of color saturation across the beam aperture is achieved during movement of said oppositely disposed color filter means.

2. The color changer according to claim 1, wherein said first and second color filter means-are movable to overlapping positions wherein said filtering regions are positioned across the beam aperture so that the effect of color enhancement of said particular color is additive.

3. The color changer system according to claim 2, wherein said filtering regions have color filtering material which are randomly diffused on said first and second color filter means.

4. The color changer system according to claim 3, wherein said first and second color filter means are first and second color filter plates slidingly positioned on opposite sides of the beam aperture, said first and second plates being simultaneously slidably movable across the beam aperture to a plurality of selected positions so as to intercept said light beam and achieve a selected enhancement of said particular color.

5. The color changer system according to claim 3, wherein said first and second color filter means are first and second color filter disks positioned on opposite sides of the beam aperture, said first and second disks being rotatably movable across the beam aperture to a plurality of selected positions so as to achieve a selected enhancement of said particular color.

6. The color changer system according to claim 1, wherein said first color filter means being positioned adjacent to the beam aperture and said second color filter means being positioned adjacent to said aperture opposite to said first color filter means, said first and second color filter means being movable across the beam aperture, and each of said color filter means enhancing a different color.

7. The color changer system according to claim 2, wherein said first and second color filter means are first and second dichroic color filter means.

8. The color changer system according to claim 7, wherein said first and second dichroic color filter means include first and second dichroic color filter plates respectively slidingly positioned on opposite sides of the beam aperture, said first and second dichroic plates being simultaneously slidably movable across the beam aperture to a plurality of selected positions so as to achieve a selected enhancement of said particular color.

9. The color changer system according to claim 8, wherein said dichroic color filtering portions are distributed in progressively greater proportion so as to progressively increase the degree of color enhancement of said particular color.

10. The color changer system according to claim 9, wherein said dichroic color filtering portions are configured as elongated rectangular strips distributed in spaced relationship within each of said progressive variable filtering regions.

11. The color changer system according to claim 7, wherein said first and second dichroic color filter means include first and second dichroic color filtering disks, respectively, rotatably positioned on opposite sides of the beam aperture, said first and second dichroic disks being simultaneously rotatably movable across the beam aperture to a plurality of selected positions so as to achieve a selected enhancement of said particular color.

12. The color changer system according to claim 11, wherein said first and second dichroic disks include a circumferential toroidal region wherein said variable filtering regions are positioned and are distributed and configured as arced strips distributed in spaced relationship within each of said progressive variable filtering regions.

13. The color changer system according to claim 12, wherein the beam aperture has an aperture diameter and said circumferential toroidal region has a toroid width at least equal to said aperture diameter, said toroidal region being positioned across the beam aperture, said first and second dichroic disks being rotatable so that said filtering regions are selectively positioned across the beam aperture.

14. The color changer according to claim 13, wherein the beam aperture has proximal and distal planes relative to said light source, said first and second dichroic disks being approximately parallel to said distal plane.

15. The color changer according to claim 13, wherein the beam aperture has proximal and distal planes relative to said light source, said first and second dichroic disks being approximately parallel to said proximal plane.

16. The color changer according to claim 4, wherein said first and second color filter plates have opposed front edges which come into filtering position across the light beam which come into filtering position across the light beam which come into intercepting position across the light beam as said first and second filtering plates are moved across the beam aperture, said front edges forming first and second notches, respectively, said first and second notches continuously defining a square during movement of said first and second filtering plates with the center of said square being coextensive with the beam axis.

17. The color changer according to claim 16, wherein said first and second notches are in the form of triangles defined by top, bottom and midpoints being capable in one position of said first and second plates of being positioned as follows:

said top points meeting at the top of the vertical axis of the beam, said bottom points meeting at the bottom edge of the vertical axis of the light beam, and said midpoints being aligned with the horizontal axis of the light beam.