Bongofish
December 08, 2019, 07:27:20 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: You can attach photos hosted by the forum rather than using an external image hosting site, this means they will stay forever and not disappear after a year or two.
 
   Home   Help Search Login Register  
Pages: [1]
  Print  
Author Topic: EL Backlighting??  (Read 3327 times)
lamaface
New Poster
*
Posts: 4


View Profile
« on: November 13, 2010, 11:36:53 AM »

Has anyone ever tried or considered Electroluminescent back lighting for LCDs?
I remember this method of lighting (commonly used in dashboards) from years ago so I went looking around and found someone on eBay that sells them.
It would run cool and on DC power.

EL Panel Sheet Pad Back Light
Store name: ELOEM
http://stores.ebay.com.au/eloem

My first impression is they would not be bright enough for backlighting. Any thoughts?


 Smiley
Logged
Drewid
Administrator
Hero Member
*****
Posts: 2290


wielder of electric crayons


View Profile
« Reply #1 on: November 13, 2010, 12:05:25 PM »

There is a make of monitor that uses EL film (Momo I think). The films have been getting brighter recently.

Good stuff:
There is a German company that makes a film that goes up  to 750 cd/m2, which is very good, You have to take a big chunk of brightness off for the darkening effect of the lcd panel, but even halving that would be comparable with a recent monitor.
Brightness can be adjusted, (70% brightness can double the lifetime from 5000 hours to 10000 hours).
It comes in kit form in international paper sizes so you can get A5 A4 A3 A2 without needing a custom order.
Has no UV emission. Some LCD panels can fade with long term exposure to UV, that's what one of the plastic sheets is between panel and backlight, a UV blocker.
Very low power, runs on an inverter at an insane voltage, but minimal current.
Low heat.

The downside:
The brightness fades gradually over its lifetime, (lifetime is considered to be how long the brightness takes to halve).
Can be expensive.
not sure how the inverter might affect jitter, but IIRC one build has used a Momo monitor successfully.

http://www.laser-star.de/produkte/diffus/light_film.htm

Logged

Games work site:  Drewnorthcott.co.uk
Personal site: Bongofish.co.uk
lamaface
New Poster
*
Posts: 4


View Profile
« Reply #2 on: November 13, 2010, 01:02:46 PM »

Thanks Drewid,


So it is possible now! I was worried also about the colour temp of the white (7000K) but it's all on the German site.
Looks promising but on the other hand it is probably too expensive and the Chinese stuff would certainly be inferior.
At least you have given me a starting point for brightness and colour temp comparisons with the Chinese product. I will ask them and see if they have their specs available.
Assuming they are correct/realistic, it just might be worth it. One of my concerns is dissipating heat from an enclosure which this could solve.
I'll also look a bit more for another supplier closer to me!

Cheers!  Grin
Logged
Drewid
Administrator
Hero Member
*****
Posts: 2290


wielder of electric crayons


View Profile
« Reply #3 on: November 13, 2010, 02:11:11 PM »

It's worth looking at specs.  It may well be that the German stuff is manufacturered in China, If that is the case than the Chinese stuff could be made on the same production line. 

The Chinese don't have copyright and don't care much about patents (which can be got around anyhow).  If a western manufacturer starts sending stuff there to be made then as often as not they'll find themselves facing competition from cheaper knock-offs of their own goods after a year or two.   
Hanvon make tablets identical to Wacom in spec even down to express keys.
Logged

Games work site:  Drewnorthcott.co.uk
Personal site: Bongofish.co.uk
lamaface
New Poster
*
Posts: 4


View Profile
« Reply #4 on: November 13, 2010, 03:30:16 PM »


Well it's a good point on the German EL. Frankly, I have no sympathy for a manufacturer that thinks it's a good idea to go to China, they are setup to copy everything and anything. They have even sold artificial eggs to supermarkets made out of industrial chemicals. But that's another story.

Back On Topic;
There's actually a few on eBay but they state 80 - 100 cd/m^2 , no where near the German stuff of 300+. No wonder it's cheap.
I couldn't find "Momo" LCDs you were referring to.

More looking is required.
Logged
Tymnus
New Poster
*
Posts: 23


View Profile
« Reply #5 on: May 29, 2011, 01:14:24 AM »

Any luck with this? Did you ever locate a supplier and give it a try? I am intrigued by the idea of using EL back lighting also. Would love any helpful tips...

Thanks!
Logged
Pages: [1]
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!