Colour wheel segments and speed
The segment layout of a single-chip DLP colour wheel, e.g. RGBRGB, RGBW, RGBCMY or RGBY.
- Standard
- Vendor disclosure
- ISO 21118
- Extension
- Status
- Standard reference being re-verified
Show the numbers
| Formula | switches/s = frame rate × revolutions per frame × segments per revolution |
|---|---|
| Layout | RGB (3 segments, equal angles — illustrative) |
| Frame | 60 Hz = 16.7 ms |
| Switches per second | 60 × 4 × 3 = 720 |
| Each field lasts | 1.4 ms |
How to compare it
Colour wheel segments
A White (W) segment boosts the white-lumens figure but not colour brightness, so check CLO. RGBRGB (6-segment) halves the time each colour block lasts, which reduces RBE.
Colour wheel speed(×)
The wheel speed as a multiple of the frame rate (2×, 3×, 4×, 6×…). Combined with the segment count, it gives the colour-switching rate.
Higher is better for RBE. The relevant quantity is colour-field switches per second: speed × number of RGB sets on the wheel.
Standard: Vendor disclosure
Marketing traps
- Colour wheel segments: Laser-phosphor DLPs have a phosphor wheel *and* often a filter wheel. 'No colour wheel' claims need checking.
- Colour wheel speed: '4×' can mean 4× of 60 Hz or 4× of 50 Hz depending on the input. Some wheels slow down for 24p.
Deep cut
Colour wheel segments. TI BrilliantColor uses the secondary colours (CMY) to lift brightness of mixed colours. It can distort colour volume unless it's disabled in accurate modes.
Colour wheel speed. LED and laser field-sequential designs can switch much faster than mechanical wheels. Each frame's colour sub-fields are electronically scheduled.
Terms on this page
Color wheel
A spinning segmented filter in lamp and laser-phosphor DLP. Its speed (2×/4×/6×) and segments (RGB, RGBW, RGBRGB, RGBCMY) affect rainbow effect, color brightness and gamut. A white ("W") segment boosts white lumens but not color lumens. ⚖ imaging.color_wheel_speed, imaging.color_wheel_segments