The present disclosure relates to a color mixer for producing a colored beam of light, for example, in a theatrical lighting fixture. In theater, stage, and other entertainment production applications, it is often desirable to project a colored light beam. Initially, this was accomplished by using colored glass, followed by colored gelatin. The current term “gel” refers generally to theatrical lighting color filters and is derived from this past use of gelatin as a color-filtering medium. Sheets of dyed polyester (called “gels”) are now standard within the industry for lighting color filter applications.
It is also desirable to be able to project more than one color from a single lighting fixture. Rotating color wheels provided multiple colors, however, such color wheels proved to be too large, and too limited in the number of colors available.
A further desirable feature is the ability to produce a colored light beam of varying hues. For example, it may be desirable to project a light beam at a stage in colors ranging from white light to a very deep shade of blue, symbolizing a transition from day to night. Gel strings accomplish this transition by comprising an assembly of numerous individual frames of color attached together to create a gel having a color gradient ranging from clear to a deep hue of a particular color, such as blue in the previous example.
Gel strings may be used in combination with a motor drive system to remotely position the desired color in front of a light source. Such motor drive systems are referred to as color scrollers and are commercially available, such as the Smart Color® line of scrollers from Apollo Design Technology, Inc. of Fort Wayne, Ind. However, color scrollers are limited to the number of individual frames that can be coupled together, thus limiting the color gradient. The highest number of frames available on color scrollers is presently 32. Designers of theatrical programs frequently need more colors than the limited palette offered by current products.
The present disclosure relates to a color mixer having a plurality of color media configured to pass a light beam such that the color media may be repositioned relative to one another to produce a color mixing effect resulting in many available combinations of color and hue.
The color mixer of the present disclosure employs a plurality of color media. The exemplary embodiment contains two color media, each color media comprising a gel string. One gel string contains graduated frames of cyan and yellow. The second gel string contains graduated frames of yellow and magenta. By combining a magenta frame with a yellow frame a shade of red is produced. Combinations of magenta and cyan produce blue while combinations of yellow and cyan produce greens.
Each of the gel strings includes a selection of hues in gradients of the cyan, yellow and magenta frames. The makeup of these two gel strings greatly increases the number of hues available in the ranges that the human eye is most sensitive. The human eye can detect extremely small changes in blue, purple and red hues. However, the eye can only detect large changes in yellow and greens. This phenomenon is documented in a color graphic known as the MacAdam ellipses. See MacAdam, D. L., Visual Sensitivities to Color Differences in Daylight, J. Opt. Soc. Am. (1942). Therefore, it is desirable to have a two-string color-mixing device that creates a large quantity of incrementally small changes in blues, purples and reds. It is also desirable for a two-string color-mixing device that creates a small quantity of incrementally large changes in greens and yellows.
The present disclosure will be described hereafter with reference to the attached drawings which are given as non-limiting examples only, in which:
The color mixer 100 of the present disclosure is shown relative to a light source 101 and its associated light beam 102 in
Color mixer 100 includes spools 106 and 107 to facilitate moving first color medium 201. Color mixer 100 also includes spools 108 and 109 to facilitate moving second color medium 202. In the exemplary embodiment, spools 106, 107, 108, and 109 may be motorized and coupled to a controller allowing an operator to remotely position first and second color media 201, 201 relative to each other and light source 101. Various portions of 201 can be positioned in the light beam 102.
First and second color media 201, 202 are positioned adjacent and apart from each other within color mixer 100, as shown in
First color medium 201 includes a plurality of color frames, including a clear frame 203, a plurality of yellow hue frames 204, and a plurality of cyan hue frames 207. Clear frame 203 is positioned near the midpoint of color medium 201. Section 204 is made up of a plurality of yellow hue frames, having the lightest yellow hue 205 adjacent clear frame 203 and deepest yellow hue 206 at one end of color medium 201. Section 207 is made up of a plurality of cyan hue frames, having the lightest cyan hue 208 adjacent clear frame 203 and deepest cyan hue 206 at the opposite end of color medium 201.
Second color medium 202 is positioned farther from the light source 101 than color medium 201. Since the light beam 102 is wider as it passes through color medium 202, the width of the color frames must be wider. Fewer frames can be assembled to limit the overall length of the gel string.
Second color medium 202 includes a plurality of color frames, including a clear frame 210, a plurality of magenta hue frames 211, and a plurality of yellow hue frames 214. Clear frame 210 is positioned offset from the midpoint of the color medium 202 due to the second color medium 202 having more magenta frames 211 than yellow frames 214. Section 211 is made up of a plurality of magenta hue frames, having the lightest magenta hue 212 adjacent clear frame 210 and deepest magenta hue 213 at one end of color medium 202. Section 214 is made up of a plurality of yellow hue frames, having the lightest yellow hue 215 adjacent clear frame 210 and deepest yellow hue 216 at the opposite end of color medium 202. There are a fewer number of yellow hue frames included in section 214, than for the other sections 204, 207, and 211. This results in a shorter color medium 202 and limits creation of an unnecessary amount of green hues.
To produce a beam of white light, first color medium 201 and second color medium 202 are configured such that clear frames 203 and 210 are aligned, allowing light beam 102 to pass through color mixer 100 without filtering, as shown in
To produce a cyan light beam, first color media is configured such that a frame of cyan section 207 of the first color medium 201 is aligned with clear frame 210 of the second color medium 202, as shown in
To produce a magenta light beam, first color medium 201 is configured such that clear frame 203 is aligned with a frame of magenta section 211 of the second color medium 202, as shown in
To produce a green light beam, first color medium 201 is configured such that a frame of cyan section 207 is aligned with a frame of yellow section 214 of the second color medium 202, as shown in
To produce a blue light beam, first color medium 201 is configured such that a frame of cyan section 207 is aligned with a frame of magenta section 211 of the second color medium 202, as shown in
As should be apparent, by adjusting color media 201, 202 to align various hues of yellow, cyan, and magenta, along with the clear frames, a full spectrum of colored light may be produced. Additionally, it is contemplated that color media 201 and 202 comprise colored portions comprising sections of continuously variable color gradient, instead of discrete hue frames. A color medium having such a continuously variable color gradient has colored sections 204, 207, 211, and 214 that gradually deepen in hue without a perceptible step in gradation. It is further contemplated that more than two color media may be utilized and still be within the scope of the present disclosure. For example, three color media may be used, one color media for each of the yellow, cyan, and magenta hues. Also, the present disclosure is not limited to theatrical gel strings, but may employ any suitable color filter media.
While an embodiment has been illustrated and described in the drawings and foregoing description, such illustrations and descriptions are considered to be exemplary and not restrictive in character, it being understood that only an illustrative embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected. The applicant has provided description and figures, which are intended as an illustration of certain embodiments of the disclosure, and are not intended to be construed as containing or implying limitation of the disclosure to those embodiments. There are a number of advantages of the present disclosure arising from various features set forth in the description. It will be noted that alternative embodiments of the disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of the disclosure and associated methods that incorporate one or more of the feature of the disclosure and fall within the spirit and scope of the present disclosure as defined by the impendent claims.
The present application claims the benefit of priority to U.S. Provisional Patent Application Ser. No. 60/970,636 filed on Sep. 7, 2007.
Number | Date | Country | |
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60970636 | Sep 2007 | US |