Talk:Backlight

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[edit] LED

I have a question about LED backlighting for LCDs, which I was very excited to hear about, since the color wavelengths could be more closely matched and presumably more efficient.

However, one of the ways I thought it might work is different than what is being done now, and I was wondering if there was any talk of doing this other way?

I had thought maybe the LCD would be MONOCRHOME, and that each color of LED would fire out of phase. So instead of 60 Hz, you'd have 180 Hz, with red, green and then blue LEDs each taking turns.

The advantage would be a high resolution picture and more efficient use of light energy.

So 1/180th of a second the mono LCD displays the image for the red color channel, and then all the red LEDs fire.

Then 1/180th of a second later, the LCD does the green image and the green LEDs fire, etc.

My friend suggested that this would not be fast enough, and that you would be a "rainbow effect", similar to the artifact caused by early color wheels in DLP sets.

I think that "rainbow effect" was fixed by varying the borders on the color wheel in DLP sets, and I wondered if a similar workaround of LED firing patterns could fix it in LCD/LED displays?

Of course another idea would be to run the whole thing at 360 Hz. So for each 1/60th of a second video frame, you'd get the sequence twice, r g b r g b. The only problem there, I realize, is the refresh rates of LCD panels. But I think they are getting close to 5 ms now.

So anyway, has anybody talked about this scheme, and is there a name for it?

Talk pages are for discussing the article. They are not forums for general discussion. 216.69.219.3 08:36, 15 October 2007 (UTC)

[edit] Laptop

What kind of backlight was usual for laptop computers of the 1990s, and what kind for modern cellphones? Jim.henderson (talk) 14:52, 15 April 2008 (UTC)