Back in the day before i found out about diy audio, I was doing some research on LEDs as a light source, and came acreoss the Luxeon leds. At the time though i dismissed using leds becuse i figuered you needed a 49,000 lumin mh lamp, but as i found with my research from above, high power leds should work fine if i modify them into the backlight correctly. If you are going to go the same rout as me, that would be great. At least we will be able to chat with each other on ideas. Another idea is to increase the volgage to the current backlight, and i may be able the get a little more light out of it before it blows. I can also try in put two more of those into the backlight (* I know this can be done, becuse the current backlight only extends on two corders of the unit *), since they are a pretty standard type of light (if you have ever taken apart a backlight). This may be enough to make the picture brighter (it is still a good picture without any modifications to the light). For now i'm am considering LED's. This time though as you probably read above, I am going to use the 4" lcd (and yes every one i know i will not get super high resolution, but i do not want a 40 foot screen) and the projector lens... forget what it is called, from suprlus shed. I belive that one was made for flat panel, so i will get a better picture than with the delta IV.
oh yea, about the flood light led aray, i think thats a little too much bang for your buck for what i am doing. All i need to do is "implant the leds into the backlight to make the picture brighter... easier said then done... but i will do it... Anyway, do have any thoughts? Oh and if you have your lens, even if the lcd is too big, try fireing it up like i did and project using the lcds backlight... you may be (slightly) supprised...
mustafa, when you used just the backlight did u make any modifications to the LCD at all? (besides turning it)
I like your thoughts about modifying the backlight. 🙂 I know on the backlight for a broken laptop screen I ripped apart a couple days ago (just to see what it was all about), there was a cold cathode illuminating a piece of diffusing plastic, and it then reflected everything into the LCD panel... are you suggesting we do something like replace the cold cathode with an array of individual super-bright LED's? If that's the case, we might be okay there. 🙂 I like the way you think. 🙂 Maybe Vince would sell us his 50 super-bright LED's at a discounted price if he wasn't going to use them anymore after his last failed attempt at using them.
--Clint
--Clint
That lens you're buying from Surplus Shed... is that the same size as the Delta IV? If so, I might be able to use it for my 5.7" LCD.
That ids exactaly what i plan to do... replace the cathode with leds... I am worried about hot spots though... hmmm. The surpluss shed lens is smaller than the delta IV, that is why i am going to use a 4" lcd with it.
I'm considering using the big 7" magnifying lens from Surplus Shed (I think it's around $30... kindof expensive but might be worth it). It has I *think* a 22" focal length, so I could put the big magnifying lens right up on the LCD, then put the projection lens about 6 inches away or so (guestimate... I didn't bother to calc this out) to shrink the 5.7" image down to around 4" to feed it into the projection lens... would I need to get a concave lens with a 22" focal length to re-parallel the light, or do you think it would okay to go into the projection lens like that?
--Clint
--Clint
HELP HELP!!!
Hi there. Well, I got two 6000 lumes halogen floodlights from Regent Lights. They were only $8.00 each. They are 300 watt. One seems to generate ALOT of heat. Imagin two of them. I'm not sure how many fans I need. Thats not my question though....
Now, I'm still not getting a good picture. I havent been using a frenzel lenz, should I? Also, I actually angled one of the lights about 4 inces directly through the LCD and into the Delta lens and it generated a brighter picture but not quite viewable for watching anything. Is this because the box is bigger than the light? What I mean is do I basically need a metal cone to go around the light and shrink down a little to the LCD screen leaving absolutely no room for air? Like a cone?
Also, If I need to use two lights can anyone gimme a discription how to angle them? Should it be kinda like a triangle with the LCDd being one side and the two lights angle to form a triangle? there would be no actual direct light shooting in the lens then would there be? Can anyone help, thanks!
Hi there. Well, I got two 6000 lumes halogen floodlights from Regent Lights. They were only $8.00 each. They are 300 watt. One seems to generate ALOT of heat. Imagin two of them. I'm not sure how many fans I need. Thats not my question though....
Now, I'm still not getting a good picture. I havent been using a frenzel lenz, should I? Also, I actually angled one of the lights about 4 inces directly through the LCD and into the Delta lens and it generated a brighter picture but not quite viewable for watching anything. Is this because the box is bigger than the light? What I mean is do I basically need a metal cone to go around the light and shrink down a little to the LCD screen leaving absolutely no room for air? Like a cone?
Also, If I need to use two lights can anyone gimme a discription how to angle them? Should it be kinda like a triangle with the LCDd being one side and the two lights angle to form a triangle? there would be no actual direct light shooting in the lens then would there be? Can anyone help, thanks!
Note by moderator: NEVER DO THIS. Apart from being highly illegal, it is incredibly dangerous. Again, unless you have a serious death wish, DO NOT under any circumstances do as is described in the above post. [/B]
What is so illegal and bad about this Mr. Moderator?
-verbose
Re: HELP HELP!!!
I have no clue what to tell you becuse i do not use halogen. They are too hot even if they were 8 bucks. I paid $60 for my fuorex loas, and they run very cool, and very white.
erroljanusz said:
I have no clue what to tell you becuse i do not use halogen. They are too hot even if they were 8 bucks. I paid $60 for my fuorex loas, and they run very cool, and very white.
Hmmm...
Verbose, could yo do me a favor, and tell me what the exact part number, brand, size lumes watts of those light oyu bought. I'm gonna try to get thughs exact ones...i don't think the home deopt by me has the ones your talking about because thats what I though I could get. I think these are way to hot....Let me know, thanks.
Verbose, could yo do me a favor, and tell me what the exact part number, brand, size lumes watts of those light oyu bought. I'm gonna try to get thughs exact ones...i don't think the home deopt by me has the ones your talking about because thats what I though I could get. I think these are way to hot....Let me know, thanks.
If you have paypal, i would sell you my two loas for 55 bucks including shipping. I still have the boxes and all the parts for them. I no longer need them for my next projector project. They are just like new. I do not think I used them more than 2 hours.
I like this idea
Verbose and HanClito,
Do me a favor,
I would like to combine your ideas into using a 10 inch TFT screen.
Please advise. Thanks.
Verbose and HanClito,
Do me a favor,
I would like to combine your ideas into using a 10 inch TFT screen.
Please advise. Thanks.
That would not be very cost effective with leds, and there is no projection lens that i know of that will project a 10" + screen.
Sweet!
I think it's great that you want to try this Harvey!
I'm still interested in seeing how this all might work, and I think it would be great to do it with a laptop screen (I'm assuming that's where the 10 inch TFT comes from).
Here's what I've been thinking of so far....
Basically just replace the CCFT with an array of high-output LED's (possibly LED emitters, not sure how much light you would need to get a projection image).
The advantage of using an existing backlight setup is that you've got a really high-effeciency diffuser and polarizing mirror setup so that you don't lose more light than you have to.
I think it has real promise -- I'm just waiting for my LCD to get in before I can try this.
This is all the information I've gathered so far, and I *think* this picture basically represents what I hope to accomplish.
Keep imagining, and keep pushing through! I still think we can make a good LED projector, we just need to find out how. 🙂
--Clint
I think it's great that you want to try this Harvey!
I'm still interested in seeing how this all might work, and I think it would be great to do it with a laptop screen (I'm assuming that's where the 10 inch TFT comes from).
Here's what I've been thinking of so far....
Basically just replace the CCFT with an array of high-output LED's (possibly LED emitters, not sure how much light you would need to get a projection image).
The advantage of using an existing backlight setup is that you've got a really high-effeciency diffuser and polarizing mirror setup so that you don't lose more light than you have to.
I think it has real promise -- I'm just waiting for my LCD to get in before I can try this.
This is all the information I've gathered so far, and I *think* this picture basically represents what I hope to accomplish.
Keep imagining, and keep pushing through! I still think we can make a good LED projector, we just need to find out how. 🙂
--Clint
Attachments
Light
Hi everyone I'm new here been reading all options on lights
found a few on the net, Thought this light might work
a little expensive, but might be worth a try.
any comments are welcome
thanks
http://www.naturallighting.com/fixtures_worklights/worklights.cfm
Hi everyone I'm new here been reading all options on lights
found a few on the net, Thought this light might work
a little expensive, but might be worth a try.
any comments are welcome
thanks
http://www.naturallighting.com/fixtures_worklights/worklights.cfm
Attachments
verbose mustafa said:
Okay, lemme' address both issues at hand here. First off, cost effectiveness (and just normal lighting effectiveness) with LED's.
Going off of that website you gave me Verbose, I found that you can buy their brightest white LED's (10,000 mcd) for $1.68 (1-9), $1.52 (10-49), and $1.36 (50-99).
Those LED's are 5 mm in diameter, so assuming that we butt them right up against each other and we have a space of roughly 8 inches (guessed side-length of 10-inch diagonal screen), that means we can fit 8 * 2.54 * 10 / 5 = 40.64 ~ 40 LED's across the bottom of the laptop LCD. That gives us a combined candle power of 40 * 10,000 = 400,000 mcd -- not bad. The question comes as to whether or not 400 candles is that much brighter than a bright LCD cold cathode flourescent backlight tube. If it's on the order of 3x or more brighter, then we might be able to project a decent picture off of it. I held a delta II lens up to a laptop screen today, and projected a decent image (albeit partial) onto a screen several feet away, in a dark room. If we can seriously brighten that backlight, we might have some viable projection opportunities here. 🙂
Note that we're NOT trying to make a 1000 lumen light source here to replace the CCFT. The optics and the polarizing mirrors and such inside an existing laptop backlight are incredibly effecient. We just need to brighten the light source. There's an excellent powerpoint presentation that explains LCD backlights here. Here's an alternate link if you prefer the www.whiteedc.com/paneltest/slide_show.ppt+lumens+ccft&hl=en&ie=UTF-8]Google HTML version[/URL] of the powerpoint. It really helped me understand backlighting, and just how effecient those optics are.
Anyway, on with the business at hand. For the moment, let's assume that 400,000 mcd is feasible as far as brightness is concerned. Financially, 40 LED's puts us in the $1.52 per LED price range, so that means our lamp array would cost $60.80... a little on the expensive side but if it means I get to use a laptop LCD with slight modification, I might be game for that. 🙂
Now as far as projecting a 10" LCD panel, I think it's a fairly simple process that just involves getting a fresnel lens with a positive focal length (convex) as big as your panel, and then a concave lens with a corresponding negative focal length that's as big as your projection lens. Here's an older drawing I made for my proposed setup so that I could use a 5.7" LCD panel through a 4 1/2" projection lens.
Keep the imagination wheels turning boys. 🙂 There's a way through, just lean on the problem until you find it.
--Clint
"It's not broke, it's just lacking duct-tape"
Attachments
Re: Light
Hanclinto, i just want to say great job keeping this thread on topic and hawkknite: I have no clue why you are talking about halogen bulbs in this thread? I do not want to be the forum troll sort of speak, but please try to post related topics. I will tell you those lights will probably be the worst investment you ever made. For about 115 bucks, you can buy a compleate 39,000 lumin Metal Halide setup. And for $60 for can get a 12,000 lumin fluorux setup, but it will make virtually no heat. So please, read the forums and find the info you need, and if you want to make a modified backlight projector, please feel free to post.
hawkknite said:Hi everyone I'm new here been reading all options on lights
found a few on the net, Thought this light might work
a little expensive, but might be worth a try.
any comments are welcome
thanks
http://www.naturallighting.com/fixtures_worklights/worklights.cfm
Hanclinto, i just want to say great job keeping this thread on topic and hawkknite: I have no clue why you are talking about halogen bulbs in this thread? I do not want to be the forum troll sort of speak, but please try to post related topics. I will tell you those lights will probably be the worst investment you ever made. For about 115 bucks, you can buy a compleate 39,000 lumin Metal Halide setup. And for $60 for can get a 12,000 lumin fluorux setup, but it will make virtually no heat. So please, read the forums and find the info you need, and if you want to make a modified backlight projector, please feel free to post.
Just a quick update...
Here's an interesting page that shows how they're doing LED backlights. It has some really good diagrams, and makes me wonder if the light dissapation patterns are that drastically different from a normal CCFT to a row of LED's. http://www.rohm.com/products/shortform/18led/led4.html
The diagrams on that page are really useful imho.
--Clint
Here's an interesting page that shows how they're doing LED backlights. It has some really good diagrams, and makes me wonder if the light dissapation patterns are that drastically different from a normal CCFT to a row of LED's. http://www.rohm.com/products/shortform/18led/led4.html
The diagrams on that page are really useful imho.
--Clint
- Status
- Not open for further replies.