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Pico/Micro Projector Human Factors Analysis

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1.1.

Mobile Projector Colorimetry

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1.1.1.

Wavelength Choice for LEDs

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1.1.2.

Wavelength Choice for Lasers

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1.2.

Projector Luminance, Image Brightness, Image Size and Contrast

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1.2.1.

Helmholtz-Kohlrausch Effect

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1.3.

Resolution

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1.3.1.

Text Legibility

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1.4.

Pico/Micro Projector Laser Safety

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Figure 1: Colorimetry of RGB LED and Laser Projectors

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Figure 2: LED Optical Power Required as Red Wavelength Varies

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Figure 3: LED Power Required as Green Wavelength Varies

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Figure 4: LED Power Required as Blue Wavelength Varies

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Figure 5: Laser Power Required as Red Wavelength Varies

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Figure 6: Laser Power Required as Green Wavelength Varies

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Figure 7: Laser Power Required as Blue Wavelength Varies

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Figure 8: Addressable Screen Sizes with a High-gain (2.2) Screen

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Figure 9: Addressable Screen Sizes with a Matte-White (1.0) Screen

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Figure 10: Addressable Screen Sizes with an Off-White (0.8) Wall

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Figure 11: Addressable Screen Sizes with a Darker (0.5) Wall

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Figure 12: Brightness Enhancement of LED vs Lamp Projectors

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Figure 13: Laser Safety Evaluation Geometry

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Figure 14: Laser Safety Evaluations

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Table 1: Properties of Various Color Gamuts in Figure 1

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Table 2: Optimum and Acceptable Peak LED Wavelengths for Displays

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Table 3: Optimum and Acceptable Laser Wavelengths for Displays

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Table 4: Illumination from Various Sources

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Table 5: Resolution Requirements for Pico/Micro Projectors

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Table 6: Minimum Resolutions for Various Market Segments

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Table 7: Text Character Counts for Various Display Resolutions

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Table 8: Text Character Counts for Various Display Resolutions and Projector Lumens

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