Page 1 of 1

LED Backlight

Posted: Thu Dec 01, 2005 4:42 am
by JPKNHTP
-JPKNHTP

Re: LED Backlight

Posted: Thu Dec 01, 2005 6:42 am
by rshayes
Most LCD displays use a plastic "light pipe" to transfer the light from a cold cathode fluorescent tube to the back of the display. The light pipe is basically a sheet of plastic with the light injected through one or two edges. Since your LEDs are already concentrating the light into a small area, it should be possible to use a light pipe to distribute the light uniformly across the display area without modifying the LEDs.

By definition, the brightness of the backlit display will be lower. You are basically taking the same amount of light and spreading it over a much larger area.

Re: LED Backlight

Posted: Thu Dec 01, 2005 8:26 am
by JPKNHTP
-JPKNHTP

Re: LED Backlight

Posted: Thu Dec 01, 2005 8:34 am
by Chris Smith
Optics can spread the LED over a large area. The hard part is finding microscope or telescope eye piece lens to disassemble that is surplus or for sale at the right price. Childrens toy telescopes are the best place to start.

A 8MM eye piece lens out of a telescope or microscope is just a tiny bit larger than the led, so space isnt the issue, and it should throw a large beam [still circular] depending on its placment.