Presentation of the DLP technology

DLP™ is a digital projection technology that is capable of providing you with a loyal picture. To be more precise, this technology is based on four essential components:

• Light source (a high powered lamp)
• Chromatic coil
• Projection lens
• And a DMD (Digital Micromirror Device).

    

A DMD chip with a microscopic view of its mirrors

The DLP™ function works with a mono chip that is used mostly for the installation of personal Home cinema installations.

The high powered lamp is often white and passes through the chromatic coil. This segments the light (blue, red and green) before reflecting it onto the DMD chip. The DMD (Digital Micromirror Device) is a semi-conductor that encompasses up to two million microscopic mirrors, fixed in rows and columns on miniscule backing plates, which are then fixed to electronic circuits. These can be moved thousands of times a second, with these micro-mirrors being activated/disabled by an electronic digital signal (converted from the video signal), which are moved either in the direction of the light or away from it towards the projection lens.

    

The micro-mirror schematic plans which make up a DMD chip

The system schema of the DLP™ mono-chip projection system

This allows you to create, via the lens, a bright or dark pixel onto the projection surface (performing for example white on the screen, the micro-mirror will reflect the lamp light onto the projection surface. The black obtained will then not reflect the light), with a pixel being equivalent to a micro mirror. In this way, to offer a HD resolution of 720p (1280x720), the DMD component will need to integrate 921 600 micro-mirrors. If they have the higher number of 2 073 600 micro-mirrors you will be able to reach a HD resolution of 1080p (1920x1080).

This photo illustrates an ant’s leg over the top of the DMD chips micro-mirrors
Allowing you to better realise their size, this is in the order of a micron.

When a micro-mirror is activated, this allows you to generate up to 1024 levels of clear grey. In the converse case, up to 1020 levels of dark grey can be generated. Each mirror will only reflect the blue, red and green light to show the pixel. This is a complex system which is similar to the eye linking to the retina, where the colours are naturally mixed to obtain their nuances. A mono-chip DMD system allows you to create up to 16.7 million colours.