Help! bright light for large cube

[wndrwmn846]

Good Morning-I really need some help. I have 20 centerpieces that are 20x20x16" cubes. They have 11x14"windows cut out from the 4 sides. Each window has a semi-transparent image in the window to make it look like a 4 sided TV. I now need to light the TV's from the inside. I purchased a river rock lantern from target (They no longer carry this item and I can not locate them anywhere!) which put out 85 lumens and was almost bright enough. The one problem was that the light was concentrated towards the middle. I am willing to go the diy/modified route I just don't know where to start. The ideal solution would light the images evenly and brightly for 6 hours and be cost effective. Thanks so much!

 

[LukeA]

What is your power source?

 

[wndrwmn846]

It would need to be battery powered.

 

[LukeA]

I figured that much. What battery are you planning to use?

 

[cheetokhan]

Good Morning-I really need some help. I have 20 centerpieces that are 20x20x16" cubes. They have 11x14"windows cut out from the 4 sides. Each window has a semi-transparent image in the window to make it look like a 4 sided TV. I now need to light the TV's from the inside. I purchased a river rock lantern from target (They no longer carry this item and I can not locate them anywhere!) which put out 85 lumens and was almost bright enough. The one problem was that the light was concentrated towards the middle. I am willing to go the diy/modified route I just don't know where to start. The ideal solution would light the images evenly and brightly for 6 hours and be cost effective. Thanks so much!

Lotsa room inside the cube? You might try battery powered fluorescent lanterns. Walmart has several to chose from.

 

[Amonra]

I would suggest a solid aluminum cube heatsink about 2 or 3 inches squared suspended from the ceiling of your cube. On each side of the alum cube with a corresponding image you would stick a Cree XR-E with no secondary optics and driven at 1 Watt each.
You would then have an even flood of at least 80 lumens going onto each image.

I made a little drawing to help:

To drive the led's you would need to wire them in a 2 series 2 parallel configuration through a 700mA buck driver into a 12V 3Ah Sealed Lead acid battery.

You can find led's here: http://www.cutter.com.au/proddetail.php?prod=cut651 ( in your case the P4 flux cold white ones should be plenty.
You can find the driver here: http://www.cutter.com.au/proddetail.php?prod=cut762

I suppose you could find the rest locally.

you would have to wire everything like this:

This setup should be ample bright and last for well over 6 hours

 

[Amonra]

sorry, I missed the cost effective part.
but i suppose with the SLA being rechargeable would make cost effective in the end right ?