Dichroic Patterning for Subtractive Color Mixing

An automated luminaire, comprising:

• a light source configured to emit a light beam;
• a color changing system optically coupled to the light source and configured to change a color of the light beam emitted by the light source, the color changing system comprising one or more color wheels;
• and
• a controller electrically coupled to the color changing system and configured to receive a control signal and to position the one or more color wheels to produce a specified color in the light beam emitted by the light source in response to the control signal,
• at least one of the one or more color wheels comprising:
• a transparent substrate;
• and
• a patterned dichroic filter coating on the transparent substrate, the pattern including:
• a first region, comprising unconnected coated dots, most of the coated dots having a substantially equal first size, a density of the coated dots varying from a lower density at a first end of the first region to a higher density at a second end of the first region;
• and
• a second region, comprising a contiguous dichroic filter coating that includes unconnected uncoated holes, most of the uncoated holes having a substantially equal second size, a density of the uncoated holes varying from a higher density at a first end of the second region to a lower density at a second end of the second region, the first end of the second region abutting the second end of the first region.