UNDER THE HOOD
While filmmaking was transformed by digital editing, digital f/x, and digicams, film projection remained virtually unchanged: White light shined through colored celluloid to illuminate a screen.
Texas Instruments' Digital Light Processing system dispenses with film altogether; the only element between the light source and the screen are the DLP's thousands of microscopic mirrors. The key component of the $185,000 Hughes-JVC projector used at select screenings of The Phantom Menace and Toy Story 2, and now of consumer devices such as the $6,999 InFocus LP330 Dragonfly portable, TI's system uses a DLP data-formatting chip to control the digital micromirrors, building the image pixel by pixel, switching off and on thousands of times per second to project an exceptionally bright, crisp image. Here's how the Dragonfly makes your home video multiplex-ready:
DATA FLOW
1 The video signal enters the projector through a) a VGA jack, b) a composite video jack, or c) an SVHS jack.
2 An NTSC/PAL/SCAM decoder chip converts an SVHS or composite video signal into pre-RGB image data, digitizes it, then sends it to the Buzzard chip (4).
3 An analog-to-digital converter chip translates RGB image data that comes through the VGA jack into 0s and 1s understood by the Buzzard.
4 InFocus' proprietary Buzzard chip scales the incoming image size to that of XGA (1,024 x 768 pixels), the projector's display mode.
5 64 megs of frame memory act as a buffer for TI's DLP chip.
The Xilinx memory controller chip to its right acts as traffic cop.
6 TI's DLP data-formatting chip toggles the mirrors at the correct moment and in the proper sequence.
7 The Motorola ColdFire processor holds the operating system that controls all aspects of the data flow.
LIGHT PATH
A A mercury arc lamp produces 120 watts of intensely focused white light.
B The color wheel holds three filters. When the red filter is in the light path, the mirrors corresponding to reddish pixels are switched on. Green light and then blue light are added to complete the image. The wheel spins at 7,000 rpm, rotating through the colors every 8 milliseconds - about twice for every frame of video.
C The proprietary InFocus prism, specially engineered for low distortion, deflects the light so it hits the surface of the Digital Micromirror Device (D). Once the DMD modulates the light, the image is reflected back down into the prism and shot through the projection lens, E.
D Manufactured with the same lithographic process used to make silicon chips, the Digital Micromirror Device holds 786,432 microscopic mirrors on its surface. Each mirror, independently actuated by electrostatic energy, corresponds to one pixel and can switch on and off up to 50,000 times a second. The brighter a pixel, the more often its mirror switches on.
Undo: Texas Instruments' Digital Light Projection is not a component in the JVC ILA-12K projector; each was used in separate showings of The Phantom Menace.
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