LED edge lighting

[Generic Eric]

Just brainstorming here, if I wanted to edge light a larger piece of plexi, say 70% of a 6'x3' sheet what type of LED and how many do I use?

Is it this kind?

[lilshawn]

i can't tell from the pictures since they are quite blurry where it counts. but they look like 3528's

SMD LED's are described as their size in MILLIMETERS DECIMAL'D. IE a 5mm x 5mm LED would be described as a "5050" or "5.0 x 5.0" wherein a 3.2mm x 1.6mm would be "3216" etc.

RGB led stips are often 5050's and are very good at edge lighting because they are much brighter than 3528's are when set up in an RGB situation.

[Generic Eric]

i can't tell from the pictures since they are quite blurry where it counts. but they look like 3528's

SMD LED's are described as their size in MILLIMETERS DECIMAL'D. IE a 5mm x 5mm LED would be described as a "5050" or "5.0 x 5.0" wherein a 3.2mm x 1.6mm would be "3216" etc.

RGB led stips are often 5050's and are very good at edge lighting because they are much brighter than 3528's are when set up in an RGB situation.

Shoot I should have just linked to the auction.  Have you done many edge lit projects?  I'd've keen to see some examples.  I'll check the auction tomorrow & make sure they are 5050s

[nitrogen_widget]

I just got a roll of 5050's from DX.com for $18 + a few bucks shipping.
I want to see if I can use them to replace a back-light in a 21" 4:3 LCD monitor.
It's an old monitor with a low resolution and parts are non-existent for it.

so if my backlight experiment fails I still have a strip of led lights to play with.

[Generic Eric]

Got a link?

[nitrogen_widget]

This is what I bought.

http://www.dx.com/p/5050-waterproof-72w-3000lm-6000k-300-5050-smd-led-white-light-strip-5m-dc-12v-287789#.U00MgFdD5hE

[Nephasth]

I use 5050s on the NephRings, they work great for edge lighting.

[Generic Eric]

I use 5050s on the NephRings, they work great for edge lighting.

Have you ever messed around with RGB?  Do you have any suggestions.  Specifically, I want to alternate colors.  See my led taito thread in project announcements

[SavannahLion]

I just got a roll of 5050's from DX.com for $18 + a few bucks shipping.
I want to see if I can use them to replace a back-light in a 21" 4:3 LCD monitor.
It's an old monitor with a low resolution and parts are non-existent for it.

so if my backlight experiment fails I still have a strip of led lights to play with.

It can be done. I have a 4:3 that's also slated to get the LED treatment. Unfortunately the inner shielding appears to be spotted welded together with tank armor. But I digress, here are a few articles on the topic using various techniques.

http://www.keithwakeham.com/lcd.htm
http://mycorner.no-ip.org/misc/ledback/index.html
http://filear.com/dnn/Home/tabid/41/EntryId/50/Repairing-broken-LCD-screen-backlight-with-LEDs.aspx
http://hackaday.com/2011/03/04/led-backlight-conversion-using-recycled-ccfl-inverter-parts/
http://blog.allgaiershops.com/2011/03/04/its-alive/

I can't advise you on the best way to proceed though. There are tons of articles in addition to the above attacking the problem from all angles. Enjoy.

[Nephasth]

I use 5050s on the NephRings, they work great for edge lighting.

Have you ever messed around with RGB?  Do you have any suggestions.

Yes. Suggestions as far as...?

[Generic Eric]

I use 5050s on the NephRings, they work great for edge lighting.

Have you ever messed around with RGB?  Do you have any suggestions.

Yes. Suggestions as far as...?

I just edited the post you quoted.  In a nut shell do you use rgb 5050s?  If so, do you have a good link?  Preferably some thing I could use withe the led wiz if that is what you are using.

[Nephasth]

These are basically what I use: http://www.ebay.com/itm/50-pcs-RGB-PLCC-6-5050-3-CHIPS-SMT-SMD-LED-Light-/230802137241?pt=LH_DefaultDomain_0&hash=item35bce12099

They require the use of resistors when wiring directly to a power supply or LED-Wiz, but resistors are not needed when wiring to a PACLED64. Very tiny solder points...

[nitrogen_widget]

I just got a roll of 5050's from DX.com for $18 + a few bucks shipping.
I want to see if I can use them to replace a back-light in a 21" 4:3 LCD monitor.
It's an old monitor with a low resolution and parts are non-existent for it.

so if my backlight experiment fails I still have a strip of led lights to play with.

It can be done. I have a 4:3 that's also slated to get the LED treatment. Unfortunately the inner shielding appears to be spotted welded together with tank armor. But I digress, here are a few articles on the topic using various techniques.

http://www.keithwakeham.com/lcd.htm
http://mycorner.no-ip.org/misc/ledback/index.html
http://filear.com/dnn/Home/tabid/41/EntryId/50/Repairing-broken-LCD-screen-backlight-with-LEDs.aspx
http://hackaday.com/2011/03/04/led-backlight-conversion-using-recycled-ccfl-inverter-parts/
http://blog.allgaiershops.com/2011/03/04/its-alive/

I can't advise you on the best way to proceed though. There are tons of articles in addition to the above attacking the problem from all angles. Enjoy.

Nice.
Thanks.
I actually have everything apart with full access to diffusion sheets & CC tubes.
My two biggest issues are... how many strips to use & can I tie into a source on the power supply that will turn the LED's off when it goes into sleep mode.

[SavannahLion]

You'll probably have to experiment to get it right on the number of LEDs. I don't see a lot of consistency in the number used in those projects other than the fact it took a couple of iterations to get it right.

Off the top of my head, there probably isn't a place directly off the power supply. I would still check but I wouldn't bank on it. I might look at the original lighting circuit for a low voltage signal or at the indicator lights for a source. You might find enough that a simple NPN transistor will do the trick. If that doesn't fly, you might be forced to build a small circuit using relays or solid state or resort to a small microcontroller like an AVR (Arduino) or PIC.