The difference between DLP and LCD

The LCD (liquid crystal display, liquid crystal display) projector contains three independent LCD glass panels, which are the red, green, and blue components of the video signal. Each LCD panel contains tens of thousands (or even millions) of liquid crystals, which can be configured to be opened, closed, or partially closed in different positions to allow light to pass through. Each individual liquid crystal essentially acts like a shutter or shutter, representing a single pixel ("picture element"). When the red, green and blue colors pass through different LCD panels, the liquid crystal opens and closes instantly based on how much each color of the pixel needs at that moment. This behavior modulates the light, resulting in an image projected onto the screen.

DLP (Digital Light Processing) is a proprietary technology developed by Texas Instruments. Its working principle is very different from LCD. Unlike glass panels that let light pass through, a DLP chip is a reflective surface composed of tens of thousands (or even millions) of micro lenses. Each micro lens represents a single pixel.

In a DLP projector, the light from the projector bulb is directed to the surface of the DLP chip, and the lens changes its slope back and forth, either by reflecting the light onto the lens path to turn on the pixel, or leaving the light on the lens path to turn off the pixel.

Comparison of DLP technology and LCD technology Full Digital Projection Display Technology Liquid Crystal Projection Display Technology
Core technology All-digital DDR DMD chip LCD panel
Principle of imaging The projection principle is to project light through a high-speed rotating red-blue-green wheel and then onto the DLP chip for reflection and imaging. After optical projection passes through the red, green and blue primary color filters, the three primary colors are projected through three LCD panels to form a composite projection image.
Clarity The pixel gap is small, the picture is clear, and there is no flicker. Large pixel gap, mosaic phenomenon, slight flicker.
Brightness High General
Contrast The total light efficiency is greater than 60% when the light filling amount is up to 90%. The maximum light fill level is about 70%, and the total light efficiency is greater than 30%.
Color reproduction High (Principle of Digital Imaging) general (limited by digital-to-analog conversion)
Grayscale High (1024 levels/10bit) The level is not rich enough
Color uniformity greater than 90% (color gamut compensation circuit to make the color consistent). There is no color gamut compensation circuit, which will cause increasingly serious chromatic aberration as the LCD panel ages.
Brightness uniformity greater than 95% (digital uniform transition compensation circuit makes the brightness in front of the screen more uniform). Without compensation circuit, there is "sun effect".
Performance The DLP chip is sealed in a sealed package, which is less affected by the environment, and has a service life of more than 20 years and high reliability. LCD liquid crystal materials are greatly affected by the environment and are unstable.
Lamp life  Use Philips original UHP long-life lamp, long life, DLP is generally suitable for long-term display. The lamp life is short, LCD is not suitable for continuous long-term work.
Service life The life of DLP chips is more than 100,000 hours. The life of the LCD panel is about 20,000 hours.
Degree of interference from external light DLP technology integrated box structure, free from external light interference. DLP technology integrated box structure, free from external light interference.

Post time: Mar-10-2022