What Is DLP ?

Digital Light Processing (DLP) is a trademark owned by Texas Instruments, representing a technology used in some TVs and video projectors. It was originally developed in 1987 by Dr. Larry Hornbeck of Texas Instruments.

DLP is used in DLP front projectors (small standalone projection units) and DLP rear projection television.

DLP, along with LCD and LCoS, are the current display technologies behind rear-projection television, having supplanted CRT rear projectors. These rear-projection technologies compete against LCD and plasma flat panel displays in the HDTV market.

DLP is also one of the leading technologies used in digital cinema projection.

In March 2008, TI announced the initial production of the DPP1500 chipset, which are micro projectors to be used in mobile devices. Availability for final products would show up in the market early 2009.

Digital Micromirror Device (DMD)

In DLP projectors, the image is created by microscopically small mirrors laid out in a matrix on a semiconductor chip, known as a Digital Micromirror Device (DMD). Each mirror represents one or more pixels in the projected image. The number of mirrors corresponds to the resolution of the projected image (often half as many mirrors as the advertised resolution due to wobulation). 800×600, 1024×768, 1280×720, and 1920×1080 (HDTV) matrices are some common DMD sizes. These mirrors can be repositioned rapidly to reflect light either through the lens or on to a heat sink (called a light dump in Barco terminology).

Rapidly toggling the mirror between these two orientations (essentially on and off) produces grayscales, controlled by the ratio of on time to off time.

Applications and Configurations

1-CHIP DLP PROJECTION SYSTEM
Televisions, home theater systems and business projectors using DLP® technology rely on a single chip configuration like the one described above.

White light passes through a color filter, causing red, green, blue and even additional primary colors such as yellow cyan, magenta and more to be shone in sequence on the surface of the DLP® chip. The switching of the mirrors, and the proportion of time they are ‘on’ or ‘off’ is coordinated according to the color shining on them. Then the sequential colors blend to create a full-color image you see on the screen.

3-CHIP DLP PROJECTION SYSTEM
DLP® technology-enabled projectors for vey high image quality or very high brightness applications such as cinema and large venue displays rely on a 3-chip configuration to produce stunning images, whether moving or still.

In a 3-chip system, the white light generated by the lamp passes through a prism that divides it into red, green and blue. Each DLP® chip is dedicated to one of these three colors; the colored light that the micromirrors reflect is then combined and passed through the projection lens to form an image.

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