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Cool Technology Stuff

March 18, 2007

Dolby Laboratories (the high-tech audio company) is in the process of acquiring BrightSide Technologies (the high tech video company), in a move that may do for picture fidelity what Dolby did for audio fidelity.

BrightSide has developed a high dynamic range (HDR) image technology that when incorporated in an LCD monitor can produce a maximumn brightness ten times greater than any commercial display while also producing a black level ten times darker. The resulting luminance range is comparable to what we encounter in the real world, in increments too small to be detected by the human eye.

Imagine the summer sun shining on a white picket fence, and the shadows in a dark basement. Imagine the searing bright whiteness of a starship's ion drive set against the inky blackness of deep space.

BrightSide does this with LCD flat-panels by constructing a backlight using a dense array of either ultra-high brightness white or tri-color LEDs (light emitting diodes). The brightness of individual LEDs in this array is driven by the screen image, from full output to off. The backlight essentially becomes a low resolution monochrome display; a conventional high-resolution LCD front panel is sandwiched with the LED array to further modulate the brightness of each element in the image.

Conventional LCD TVs uses backlights that provide even light across the full area of the display, and of constant brightness from one moment to the next. If you make the backlight brighter to make the brightest parts of a scene more realistic, the darker areas will get brighter as well. So you compromise.

The crystals in each pixel twist to allow varying amounts of light to pass through the three colored sub-pixels to the viewer, but even when the crystals are in the full "off" position, they still allow a small amount of light to leak through. "Black" can never be truly black.

With a BrightSide display, there is no light to leak through the crystal in black areas of the scene, because the LEDs behind those areas are turned off. That means the LEDs can be turned up really bright when and where needed without affecting dark areas.

Brightside Technologies makes these displays for specialized scientific and other uses; the apparent intent is to further develop the technology for mass market consumer video displays. The BrightSide technology reportedly might also be adapted to front and rear projectors as well as flat-panels.

See www.brightsidetech.com for more info.

Texas Instruments has developed technology to drive solid-state LED arrays for DLP sets that will increase contrast ratios beyond 100,000:1. TI had a prototype on display at the Consumer Electronics Show in January that took advantage of special features built into a new 0.65" 1080p DLP chipset. (Samsung will use this chip in several 2007 products.)

Technical details on TI's approach were not available. In the past light source brightness has been controlled for the whole frame (dark scene or light scene averages), but I can imagine techniques whereby the luminance applied to smaller areas within a frame could be individually varied in DLP sets.

Texas Instruments has been bullish of late on the use of LED illumination in TVs using its DLP chips.

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Plasma TVs are showing more signs of either going Full-HD or going bust.

A report in the Asian TV trade press cited an analyst who expected that by the end of the year, 42" LCD and plasma flat-panels will be selling for the same price. The difference will be that the LCDs will be Full-HD (1920 x 1080) and the plasmas will not. The analyst expects that under those circumstances, consumers will choose the high-resolution LCD flat-panels.

The plasma market is expected to start dropping by 2009 while the LCD market will be increasing by double digits.

With companies like Sharp moving to 8th generation LCD plants optimized for efficiently producing larger (50" range) panels, that will be the next battle ground.

Philips has now announced that it will be phasing out its plasma sets, although still selling larger sets in the US for the time being.

Hitachi will introduce three new Full-HD (1920 x 1080) plasma models by the end of the year. These include 42", 50", and 60" sizes.

Hitachi will also have "1080" plasma sets with less-than-Full-HD resolution, to wit: 42" with 1024 x 1080 pixels and 50" (1280 x 1080).

Hitachi also markets Full-HD LCD flat-panel TVs.

Pioneer has just announced the introduction of a new 50" 1080p plasma set that can "deliver cinematic picture performance," as from Blu-ray Disc 1080p output. Full-HD.

The Pioneer PDP-5000EX will also input and display 1080/24p native movie signals, at a 72 Hz refresh rate. No 3:2 pulldown required. That's definitely good.

The set is targeted for professional use, major film studios and authoring houses. Translated, that means that it's scary expensive now but the technology will get cheaper in time.

What's under the hood?

The Deep Waffle Rib Structure makes each cell deeper to increase overall phosphor area for a brighter image. By casing each cell with horizontal ribs, light leakage is diminished from neighboring cells for sharper, more accurate images. A new T-shaped electrode prevents misfiring of individual cells despite the fact that each individual cell is half the size as previous generations.

The Crystal Layer sandwiched between the plasma glass and the individual light cells conducts energy more efficiently so each cell is charged and discharged at a faster rate, improving contrast and brightness while using less energy.

The PDP-5000EX will be available in the U.S. this spring with pricing TBA.