Insight Media recently learned that LED backlight solution provider Global Lighting Technologies (GLT) (Brecksville, OH; www.glthome.com) is going to introduce a new family of LED light guides with plans to demonstrate a 24" LCD-TV with an LED backlight at SID ‘06 in June.

Steve Sechrist
Senior Analyst and Editor
of Projection Monthly &
Microdisplay Report

To understand the significance of this announcement, we have to go back to a presentation given last month at the Strategies in Light (SIL) Conference held in San Francisco. There, Seoul Semiconductor VP, Dr. Jae Jo Kim, listed low efficiency (high cost) as the number one obstacle to large LCD adoption of LED lighting particularly, the number of LEDs required to adequately replace today’s cold-cathode fluorescent lamps (CCFLs).

Enter GLT, a company that has primarily targeted the small-display and monitor market supporting sizes up to 15.4 inches - until now. We saw a prototype demonstrated at SID ‘05 that used only one to three white LEDs to illuminate an LCD panel.

The new system also uses half to one-third the number of LEDs required for conventional designs. GLT says it is working with a major manufacturer on this project, although it declines to say who at this point. Company representatives also say the technology can be scaled up to larger sizes. A 32-inch LCD-TV backlight is in the works, and even larger sizes are possible

GLT’s announcement of support for larger sizes - coupled with similar announcements from Diguang Electronics and Cree, Inc. - means we may begin to see a low-cost, LED-backlit LCD-TV much sooner than experts were predicting.

As an example, at last month’s SIL conference Kim predicted a low 0% LED backlight adoption rate for 21-inch LCDs and a 0.4% rate for 32-inch LCDs in 2006 as a result of the 4.9X and 3.3X cost advantage CCFLs have over LEDs in these sizes. At the current rate, according to Seoul Semi and Dr. Kim, it would take LEDs until 2008 just to hit a 38% replacement ratio; the tipping point that jumps 32-inch displays to 80% LED backlight penetration would come in 2009.

The efficiency threshold is much higher for CCFLs in the smaller 21-inch size, so Kim predicts only a 45% LED replacement ratio in that size by 2009.

But why all the fuss? Some key advantages of LED over traditional CCFL technology include expanded color gamut and long life, facts not lost on LCD-TV product designers hungry for any advantage over the rival plasma technology. Sony and Samsung both demonstrated very high-end LCDs using LED backlights at CES. While the image was "stunning," the sets were too expensive for Samsung’s blood, and Sony is only shipping in very limited quantities under the Qualia brand.

GLTs LED light guides are very compact, permitting thinner displays and unique applications ranging from electronic microdisplay viewfinders to small LCD panels for camera and camcorder monitors, mobile phone displays, PDA keypads, programmable touchscreens, instrumentation and automotive displays.

Suffice it to say that backlights fabricated with the new light guides offer integrators the promise of higher brightness, greater efficiency, reduced part count and lower cost. And it’s the lower cost that, if significant, can reshape the adoption curve of LED technology and bring some pretty impressive displays to market much sooner than we once thought possible.