September 3, 2009

By Gary Reber

Digital Projection International (DPI), an Emmy® Award-winning manufacturer of high-performance projection systems, announced a major enhancement to select TITAN and LIGHTNING 1080p, sx+ and WUXGA models with the latest lens mount micro and updated firmware. Intelligent lens memory, or ILM, allows each projector to store specific lens zoom, shift, and focus values to specific preset positions. The ILM feature is easy to implement and even easier for end users to recall.

To initiate the lens memory, you must first calibrate the zoom and shift functions. This allows the electronics to “learn” the zoom, focus and shift range for the specific lens installed in the projector. Once the lens calibration is complete, up to 10 specific lens positions can be stored in preset locations. When the user selects one of those presets (either by remote or RS232), or a source associated with a preset, the mount will reposition the lens to the previously defined zoom, shift, and focus settings. The ILM landing accuracy is superb, averaging within two pixels over repeated cycles.

Although application possibilities are numerous for a projector with intelligent lens focus, zoom, and shift capabilities, the majority of requests are raised by Home Cinema integrators. High definition video is distributed on standard def and Blue Ray DVD’s in a variety of aspect ratios. Currently, the most common way to optimize a home theater for the display of varying aspect ratio content is to use a fixed height screen with a 2.35 native aspect ratio and movable side masking that can reduce that aspect ratio, along with a projector equipped with an anamorphic lens. If the video being presented is a 16X9 (1.78) aspect ratio, that video fills the projector’s 1080p (or 720p) DMD(s), and the 2.35 screen is masked to produce a 1.78 aspect ratio screen. If the video is 2.35, the projector’s video processing is used to vertically stretch the image to “fill in” the horizontal black bars.

The anamorphic lens is then placed in the light path to horizontally stretch the image, resulting in a geometrically correct 2.35 image that uses the full native resolution the projector offers. While the anamorphic approach delivers maximum projector resolution and lumens for 2.35:1 content, it also adds video processing, rectangular pixels, reduced contrast ratio, and a lot of additional hardware, optics, and costs. Also, since the anamorphic solution only provides a fixed 1.33 horizontal stretch, it cannot fully accommodate intermediate aspect ratios such as 2.40, 2.30 or 2.25.

With the benefit of ILM, the projector, within the limitations of the zoom range of the lens, can actually zoom in to fill a full 1.78 screen, and zoom out (increasing the overall width of the projected image) to fill the unmasked 2.35 screen. Although this does result in 30% larger pixels on the screen surface, by employing ILM, no anamorphic lens is needed. This simplifies the installation, reduces the total system cost, eliminates the need for the additional video processing and the associated artifacts, assures that maximum contrast is maintained and optical distortion is minimized. Since DPI’s ILM functionality allows for up to 10 specific presets, in addition to 1.78 and 2.35, additional lens position presets can be assigned to support 2.40, 2.30, 1.85 or even 1.33 aspect ratios.

Digital Projection International offers an extraordinary array of over 40 single-chip projectors, as well as over 30 powerful 3-chip DLP® displays. The company will be showing their entire range of efficient Home Entertainment projection displays at CEDIA ‘09, booth #519, from September 10-13, 2009.

Tags: - equipment - - Digital Projection International (DPI) - - Titan - - Lightning - - 1080p projectors - - intelligent lens memory (ILM) - - sx+ - - WUXGA -