The story begins with my sitting in my home office getting ready to write an illustrative article on how the "green" aspects (read that environmental) of LED versus CCFL in LCD backlighting will ultimately share center stage along with improved performance and in comes a note from a friend telling me about a new screen technology that will "knock my socks off". Never one to pass up an opportunity to have my socks knocked off, I began to do a little digging into this new technology and here is what I have found.

Alan Brawn
Insight Media Consultant

The inventor of this new screen technology is Luminoz Inc., a manufacturer of projection screens and other optical materials now based in Japan. Luminoz is a venture company originally established in the United States in 1999. The headquarters is moved to Tokyo in 2002. The current main shareholders of the company include Globis Capital Partners, Works Capital Inc., Mitsui & Co. Ltd. and The Dow Chemical Co. They claim to have developed a screen that can reduce the depth of a rear projection TV to about 12 cm! Not since the days of InFocus and their slim rear screen designs has a quantum leap in the thickness or more correctly thinness of RPTV come to the forefront. Now before we go any further, I have not seen the screen technology and will wait to pass judgment but here is what we know at this point.

From a technology and design perspective, there are several apparent breakthroughs in their design including the elimination of the need for a large, expensive and sometimes cumbersome mirror that is necessary in the existing RPTVs. In addition, the current 2 ply Fresnel and lenticular screen "sandwich" can be replaced with a screen consisting of a single sheet. The company says "The sheet has a single-piece structure that integrates three layers: the layer called the "curve lens," the "black block layer" and the diffusion layer. The curve lens has functions equivalent to those of mirror and Fresnel lens, the black block layer can serve as black stripes and the diffusion layer can act in place of a lenticular lens."

Luminoz further explains, "In a rear projection TV employing this screen, a light projected from just below the screen is totally reflected by the curve lens so that the reflected light is collected on transparent portions of the black block layer. Then, the light goes through the diffusion layer to be displayed on the screen. To reduce the thickness of a rear projection TV, the light source must be placed closer to the screen." In this design, Luminoz says they project the light from directly below the screen by the employment of the curve lens. In this way they eliminate the large mirror and reduce the thickness of the RPTV to as thin at 12 cm.

The company also claims a substantial increase in contrast with the new design. Luminoz says, "The increased performance is accomplished because the light subjected to total reflection on the curve lens is once condensed on the front face of the screen and by using the transparent portions of the black block layer as the light collection portions, the area of the black portion can be increased in the black block layer, resulting in a higher contrast ratio on the screen. "

Accordingly Luminoz explains, "The black contrast ratio, which is about 70% in the existing screens, can be increased to about 90% because the gap between the transparent portions (pitch of black portions) is so minimal. The black block layer is transparent at the time of production, but it is blackened by the irradiation of a special light."

In visiting their uniquely designed web site www.luminoz.com you will see that they have done what appears to be a good deal of R&D work in the area of plastics and polymer films for every niche of the display industry. In this case, Luminoz used its proprietary polymer sheets that are capable of diffusing light in different directions for the diffusion layer. This layer provides a similar function equivalent to that of a lenticular lens in a traditional RPTV design. The new sheet "is composed of two kinds of polymers with different refractive indices regularly aligned in a vertical direction. In this way, the phases are displaced with respect to each other by birefringence, thereby enhancing the diffusion. "

Press reports tell us that Luminoz is planning to commercialize the new screen technology for use in 65-inch or larger rear projection TVs sometime in 2008. In addition, the company expects that the product is also applicable to backlight units of large size LCD panels. As noted earlier, I have not seen the technology in action but if they perform as claimed, it will be interesting to see the impact on the display market. We have seen flat panel prices decline and recently stabilize but pundits tell us we are in for another round of price drops as we near the end of the year. With new developments such as this it will be interesting to see if the RPTV market becomes energized once again for those folks who want the 60 inch and greater flat panel displays but cannot afford the high prices and will settle for a little more thickness than plasma of LCD provide. Only the proof of performance will tell us whether Luminoz has a winner on their hands or not. Stay tuned for more.

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