Comments on: LED LCD backlight replacement

By: Mac

Mac — Fri, 16 Sep 2011 13:12:51 +0000

Will LED’s operate safely when connected in series?

By: Thomas E. Reed

Thomas E. Reed — Thu, 11 Oct 2007 19:46:04 +0000

Where is the article? The link is gone. If someone has it, could it be posted to the site as a PDF or something?

By: Roy

Roy — Fri, 27 Jul 2007 11:35:35 +0000

i just want to ask something about backlight. some camera fones has a built-in flash, and for some the flash is just a bright backlight. i own a nokia 5700 and it has one. may i know if the 5700′s camera flash replaceable, but not with another backlight but an infrared emitting diode (hsdl-4220 to be exact)? i want to take pictures in total darkness with my fone. please tell me if it’s possible and if so, how to do it and what should i need (tools, IR ed, resistors, etc). please help!

By: Martin D

Martin D — Mon, 14 May 2007 12:08:23 +0000

Dear Friends,

please help me with the following problem. I saw most of the sites postes here, and I don’t have experience or proper training in electronics.
I want to replace the fluorescent tubes with leds on 19 inch monitor (AG Neovo KB-19), but I don’t know how to make it work with the tubes disconected, because the electronics of the monitor turns it off when the tubes are disconected or when it can’t light one of them, I think. Seeing all of your work, I imagine that there is a way to eliminate them…
Are you so kind to indincate me a simple way to achieve this, on the adress mpclarice@yahoo.com.
Thank you, Martin.

By: newb

newb — Sun, 18 Feb 2007 12:54:04 +0000

umm…. im trying to do the same thing with my old lcd monitor, but mine has two sets of fluorescent tubes. It says they run on 3kV, so it there some way to integrate the LED’s into the monitor, without having to create a seperate board for the LED’s and running it with a seperate power supply

By: john

john — Wed, 31 Jan 2007 19:54:25 +0000

I did a backlight upgrade using 1w luxeon high brite led's... I was able to get this screen to be 100% sunlight visable, but it had to be liquid cooled....

check it out here:

http://www.mp3car.com/vbulletin/showthread.php?t=43743

By: PatulaWiFi

PatulaWiFi — Thu, 11 Jan 2007 08:09:24 +0000

I did this to a LCD monitor back in september 06, I use 27 UltraBright LED's on each side (54 in total) and a 5V external AC adapter directly as a power source, it works fine

until today it still works ok, none of the LEDs burn yet :)

Here's my version of this hack:

http://arribasanjuan.com/webs/patulawifi/electronica/lcdleds/index.htm

By: NFNNLN

NFNNLN — Thu, 11 Jan 2007 07:39:49 +0000

"LG raises the bar by ditching the fluorescent backlights from most LCDs and using a matrix of light-emitting diodes. In addition to way deeper color, the LEDs give Samsung that ability to selectively darken or brighten the backlight in different parts of the screen. This yields a contrast ratio of 100,000 to 1, they say."

An LED matrix is the way to go!

By: japroach

japroach — Thu, 11 Jan 2007 00:43:53 +0000

Interesting.. I would actually avoid the superbrights as it would result in much less uniform lighting (assuming less were used to compensate for their higher output). They might also require heatsinking.

Best would probably be a huge strip of surface mount LEDs, say 50 or more per side :).

And it looks like cold cathodes are a fair bit more efficient than an LED atm.. so we wont see any decrease in power usage.

By: Fragged

Fragged — Wed, 10 Jan 2007 22:48:36 +0000

Nice, just when I was looking at doing something like this to an old laptop LCD...

I wish there was more documentation, but seeing as i've already dissasembled the laptop without any photo's or documenting any of it it I cant really complain :)

One question, do I _NEED_ an inverter to replace it with LED's, is there any way out of it?

By: kasmoie

kasmoie — Wed, 10 Jan 2007 18:15:12 +0000

chchceck it outt!

http://led.linear1.org/led.wiz

By: dioxide

dioxide — Wed, 10 Jan 2007 08:37:02 +0000

any of you know if you can use acrylic cement on leds? that would be fantastic, as that type of cement actually melts the two parts together. ive only use it with plexiglass, but if the plastic of the led is compatible, it would seem like flattening the dome and melding the led directly to the difuser would be the most efficient way of passing all the light. no idea whether it will make big hotspots though. maybe ill try it, make a small backlit wet-erase board or something.

By: TJ

TJ — Wed, 10 Jan 2007 08:11:59 +0000

Not to be an ass, but we already have seen this done on a Jornada.

http://www.hackaday.com/2006/05/23/ccfl-backlight-replaced-with-white-leds/

By: neg

neg — Wed, 10 Jan 2007 07:07:16 +0000

where did the contest entries go? i liked those…

–neg

By: Jim

Jim — Wed, 10 Jan 2007 05:31:25 +0000

as #5 said, when the leds burn out, it will force the current through less pathways, increasing the current through each. (this phenomena can be seen with some old-school christmas tree lights wired in parallel). A solution to the runoff caused by too much current as well as a solution to his note that current will flow unevenly is to use one current limiting resistor for each LED, with the resistor, LED segments in parallel. This solution is a bit more wiring and a tiny bit more expensive, but it is much more versatile and immune to runoff.