Color changing device for illumination purposes

• US 5,790,329 A
• Filed: 09/27/1995
• Issued: 08/04/1998
• Est. Priority Date: 04/21/1994
• Status: Expired due to Fees

• Current Assignee: Feddersen-Clausen Oliver, Welm Klaus
• Original Assignee: Feddersen-Clausen Oliver, Welm Klaus
• Inventors: Klaus, Welm, Oliver, Feddersen-Clausen
• Primary Examiner(s): Shafer, Ricky D.
• Application Number:
  US08/534,739
• Time in Patent Office: 1,042 Days
• Field of Search: 359/887, 359/889, 359/890, 359/891, 362/166, 362/167, 362/168, 362/293
• US Class Current: 359/887
• CPC Class Codes: F21S 10/02 changing colors F21S10/002 - F21S10/007, F21S10/04 take precedence
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios

Abstract

A color changing device provides a continuously variable light color by means of the introduction of dichroic color filters into the light path of an illumination device. In the subtractive color mixing method for mixing of colors in an illumination apparatus according to the invention dichroic filters are provided parallel to each other and transverse to the beam path of the illumination apparatus, wherein the filters can be introduced into the beam path continuously and independently, so that a continuous mixing is achieved. At least four filters are used and wherein in view of the wavelength a broadband high-pass and a broadband low-pass, and two broadband band-stops are used, wherein the transmission regions of the two band-stops partly overlap so that with the filter combinations dominant colors with a high saturation can be generated.

Claims

1. A subtractive color mixing device for mixing of colors in an illumination apparatus comprising

at least four dichroic filters provided parallel to each other and transverse to the beam path of the illumination apparatus and capable of being introduced into the beam path continuously and independently so that a continuous mixing results, the filters including a broad high-pass, a broad low-pass and two broad band-stops, wherein the transmission regions of the two band-stops partly overlap so that dominant colors with a high saturation can be generated from filter combinations.

2. The subtractive color mixing device according to claim 1, wherein the transmission regions of the high-pass and low-pass partly overlap.

3. The subtractive color mixing device according to claim 1, wherein at least five filters are provided, the additional filter being a band-pass with respect to the transmission.

4. The subtractive color mixing device according to claim 3, wherein at least six filters are provided, the additional filter being a band-pass with respect to the transmission.

5. The subtractive color mixing device according to claim 4, wherein the six dichroic filters have the following approximate transmission regions:

magenta≈

380 nm to 450 nm and 650 nm to 780 nm,

pink≈

380 nm to 490 nm and 580 nm to 780 nm,

green≈

500 nm to 540 nm,

light green≈

480 nm to 590 nm,

cyan≈

380 nm to 520 nm and

yellow≈

520 nm to 780 nm.

6. The subtractive color mixing device according to claim 3, wherein the transmission regions of the high-pass and the low-pass do not overlap.

7. The subtractive color mixing device according to claim 1, wherein the four dichroic filters have the following approximate transmission regions:

blueviolet≈

380 nm to 490 nm and 650 nm to 780 nm,

redviolet≈

380 nm to 450 nm and 570 nm to 780 nm,

cyan≈

380 nm to 560 nm and

yellow≈

500 nm to 780 nm.

8. The subtractive color mixing device according to claim 1, wherein the filters are arranged with a small gap between each other.

9. The subtractive color mixing device according to claim 1, wherein the device includes a control element for controlling the movement of the filters.

10. The subtractive color mixing device according to claim 9, wherein the device is in the form of a plug-in cassette adapted to be arranged in an illumination apparatus comprising a stage spotlight having imaging optics, between objective lenses in the region of the illumination field image of the lamp of the spotlight, the control element being situated outside the body of the spotlight.

11. The subtractive color mixing device according to claim 10, wherein the control element comprises a microprocessor which converts two analogue or digital multiplex signals into control signals, the analogue or digital multiplex signals defining the color saturation and hue.

12. A subtractive color mixing device for mixing of colors in an illumination apparatus comprising:

at least four dichroic filters provided parallel to each other and transverse to the beam path of the illumination apparatus and capable of being introduced into the beam path continuously and independently so that a continuous mixing results, the filters including a broad high-pass, a broad low-pass and two broad band-stops, wherein at least one of the band-stops includes a high-pass and a low-pass, and wherein the transmission regions of the two band-stops partly overlap so that dominant colors with high saturation can be generated from filter combinations.