2012
2012 Projector Specifications 2 Stuart Nicholson System Architect
System Specification Space Constraints System Contrast Screen Parameters System Configuration Many interactions Projector Count Resolution Mission Type Feature Discrimination Maintenance Schedule IG Hardware Realism Database Gamut 3
System Specification Space Constraints System Contrast Screen Parameters System Configuration Many interactions Translation to projector specification is not obvious Projector Count Resolution Mission Type Feature Discrimination Maintenance Schedule IG Hardware Realism Database Gamut 4
System Specification Space Constraints System Contrast Screen Parameters System Configuration Many interactions Translation to projector specification is not obvious Will discuss interactions with projector specifications Projector Count Resolution MTF Color Error Lens Type Uniformity Modulators Pixel Size Feature Discrimination Illuminator Type Contrast Maintenance Schedule Lens Offset Brightness Color Gamut Throw Ratio Smear Reduction Frame Rate Image Geometry tin tout Latency IG Hardware Mission Type Realism Database Gamut 5
Interactions Between Projector Parameters Color Error Lens Type Uniformity Contrast Lens Offset Throw Ratio Image Geometry MTF Brightness Smear Reduction tin Latency tout Frame Rate Pixel Size Modulators Color Gamut Illuminator Type 6
Interactions Between Projector Parameters Contrast Uniformity Brightness Smear Reduction tin Latency tout 7
Brightness Interactions Technology choices Illuminator type Pixel size Design choices Contrast Uniformity System choices Color gamut, white point Lens type Smear reduction Lens shift 8
Brightness Interactions Technology / Design Technology choices Illuminator type Illuminator type Pixel size Design choices Contrast Uniformity System choices Color gamut, white point Lens type Smear reduction Lens shift Available raw lumens Lifetime Cost Physical and optics size Pixel size Resolution vs optics size Contrast and uniformity Apertures limit brightness Increasing uniformity reduces brightness 9
Brightness Interactions System Technology choices Color gamut Illuminator type Pixel size Design choices Contrast Uniformity System choices Color gamut, white point Lens type Smear reduction Lens shift Color saturation Brightness profile over gamut Lens type Apertures in lens for contrast and depth of field Throw ratio Smear reduction Hold time (display time) Lens shift Apertures in lens 10
Brightness vs Color 140 120 100 80 60 40 20 y=7000 y=231 y=250 y=273 y=300 y=333 y=375 y=429 y=500 y=600 y=750 y=1000 y=1500 y=3000 11
Brightness Measurement System parameters Color gamut Frame rate Smear reduction Instrument Define Measurement / Technique White flat field Color checkerboard Center, 9-pt, 13-pt 12
Contrast Technology choices Pixel size Design choices Brightness Uniformity System choices Lens type Throw ratio Lens shift 13
Contrast Interactions Technology / Design Technology choices Pixel size Design choices Brightness Uniformity System choices Lens type Throw ratio Lens shift Cost Physical and optics size Pixel size Resolution vs optics size Brightness and uniformity Apertures improve contrast Increasing uniformity reduces contrast 14
Contrast Interactions System Technology choices Lens type Pixel size Design choices Brightness Uniformity System choices Lens type Throw ratio Lens shift Lenses with shift capability may increase spill light Apertures in lens improve contrast Throw ratio and lens shift Contrast can vary with throw ratio and lens shift due to changing effectiveness of apertures in lens (throw) and system (shift) 15
Contrast Measurement System parameters K1 W1 K2 W2 Typically specified at zero lens shift W3 K3 W4 K4 Instrument Define Measurement / Technique K5 W7 W5 K7 K6 W7 W6 K8 Flat-field (sequential) ANSI checkerboard Spill 16
Latency 17
Latency Smear reduction (reduction of hold or display time) can reduce latency Increasing frame rate can significantly reduce latency IG Output Frame n Transport Latency Video Cable Video Processing Modulated Light out Projection Lens Frame n Frame n Video Processing Latency Frame n Imaging Latency t0 t1 t2 t3 t4 t5 18
Latency Interactions Technology choices Geometry: IG, box or projector Design choices Algorithm System choices Image geometry Smear reduction Frame rate 19
Latency Interactions Technology choices Geometry: IG, box or projector Geometry: IG, box or projector Design choices Algorithm System choices Image geometry Smear reduction Interface with calibration system Algorithm Image geometry Pixel shifted vertically up the most (default landscape orientation) drives latency Frame rate Smear reduction and frame rate Can reduce latency 20
Latency Measurement System parameters Typical geometry Smear reduction Frame rate Instrument Define Measurement / Technique Last pixel to last light (L->L) First pixel to last light (L->L + transport delay) IG Vertical Sync Data Active Projected Light Projector First-to-First Last-to-Last (recommended) F IV F ID L ID L IV F OIL F OFF L OIL L OFF PIN diode Transport = F( frame rate ) Video Processing = F( geometry ) Imaging = F( frame rate, smear reduction ) 21
Uniformity Interactions Technology choices Pixel size Design choices Brightness Contrast System choices Lens type Lens shift 22
Uniformity Interactions Technology choices Pixel size Design choices Brightness Contrast System choices Lens type Lens shift Optics complexity Pixel size Diffraction effects Brightness and contrast Increasing uniformity (optically or electronically) reduces brightness and contrast Lens type and shift Shift-capable lenses improve uniformity Uniformity typically y degrades away from zero shift 23
Uniformity Measurement System parameters Typically specified at zero offset Instrument Define Measurement / Technique Typically without electronic correction White flat field 9-pt, 13-pt, 17-pt, center-to-corner 24
Smear Interactions Technology choices Design choices Algorithm Brightness System choices Frame rate Latency 25
Smear Interactions Technology choices Design choices Algorithm Brightness System choices Frame rate Latency More modulators permits shorter display time (to a point) Algorithm Algorithm choices can impact tradeoff between smear reduction and hold time Brightness Higher brightness permits shorter hold time (to a point) 26
Smear Interactions Technology choices Frame rate Design choices Algorithm Brightness System choices Frame rate Latency If projector is capable of the increased refresh rate, increasing frame rate reduces smear with less impact on brightness Latency Reducing hold time can reduce latency 27
2012 Thank you. Questions?
2012 Thank you. Questions?