Versatile Fiber Optic Backlights Can Handle Membrane Switches With Irregular Geometries

Strongsville, OH, June 2006 - UniGlo® patented fiber optic backlighting technology from Lumitex® can be designed to provide bright, uniform, low-power, low-cost backlighting for membrane switch OEMs who require irregular geometries.

Traditional membrane switches have been rectangular in shape, but some OEMs have been designing membrane switches with other, more unusual shapes to help differentiate their products in the marketplace.

"What we're starting to see is OEMs who realize the versatility of UniGlo® to meet designs that require something other than a rectangular shape," said Walter Schulz, Applications Engineer, Fiber Optic Lighting, at Lumitex. "UniGlo® backlighting can give them the brightness, uniformity, durability and low power consumption they're looking for in the shape of an oval, or a rectangular panel with a curved die cut shape at the end, or other custom shapes."

Applications include HVAC controls for commercial refrigeration, programmable thermostats that can ramp up and down, hot tubs and spas, medical devices, and dozens of others in a range of industries.

In operation, UniGlo® fiber optic panels are positioned between the overlay and the circuit board/metal dome assembly. The fiber optic tail is routed, around any obstacles if necessary, to the LED, which is soldered into an appropriate space on the circuit board.

Since UniGlo's fiber optic technology is well positioned to take advantage of ongoing advances in LEDs, the panels can backlight a large area with one LED light source (up to 4" x 6") and, since they are so thin (0.013"), they don't interfere with the tactile feel of the switch when the dome is depressed.

With brightness as high as 75 Ft-L, they can provide a clearly readable display in dimly lit areas. Power consumption is low (2-4 VDC, 5-30 mA for a single-LED backlight), the panels generate no heat, EMI or ESD, and they are impervious to moisture, humidity and heat. Fiber optic panels have been tested to over 5 million actuations and provide backlight lifetimes up to 100,000 hours (depending on the LED light source used).

"Another advantage to OEMs is that the flexibility of UniGlo® technology allows prototypes to be available in 1-4 weeks," noted Schulz. "Tooling costs are low, keeping the overall cost of the backlight assembly very moderate compared to other technologies."

Cost for UniGlo® panels ranges from $0.70 for a panel with a 0.40" x 4" viewing area and no LED in quantities of 100,000, to $4.00 for a panel with a 1.35" x 3.50" viewing area and one white LED in quantities of 5,000. For details, contact Lumitex with your application.

For more information on Lumitex's UniGlo® membrane switch backlighting, contact Lumitex Inc., 8443 Dow Circle, Strongsville, OH 44136. Tel: 1-800-969-5483; 440-243-8401;
Fax: 440-243-8402; E-Mail: Web:

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