I came across this interesting project. The guy decided to make a UV PCB exposure box made of UV light LEDs. The main reason why he used LED was the power dissipation and compactness. Assuming that one UV tube would take about 6W while one UV LED would take about (20mAx3.2V=64mW). Most of that energy UV tubes dissipate as heat energy.
So he took:
54 x UV LEDs of 400nm (6000 – 7000 mcd) – 100 units in Ebay costed 12€;
18 x 68ohms resistors 1/4W – 0,36 €;
1 connector – 0.50€;
1 electrolytic condenser of 2200uF – 30v;
1 Eurocard Plate 100×160 about 5 € ;
A 12V power supply powers the plate of LEDs. LEDs’ radiation angle is 20º, so they took about 8cm heigh box that light could cover the whole PCB area when distances between LEDs are 18mm.
Download circuit and PCB from original site.
Were you able to expose the PCB properly? I mean did it do good job?
What about the intensity variation in LEDS? Let me know what results you found?
However, I miss some practical information that I would consider to be quite important, such as:
– what is the mean wavelength of the UV LEDs used? Is it in the 450-480 nm range, 380-400 nm or anythoing else?
– what is approximately the exposure time?
– is the exposure uniform accross the whole area? With this kind of geometry I would expect that there should be “lighter” spots above the center of each square formed by four adajcent LEDs. (I would expect a more uniform pattern if the LEDs were placed in a hexagonal grid)
Sorry, it is 400 nm, written in the article. I think it was a sort of UV blindness – maybe from the photos 🙂
Please could you tell me where I can obtain a PCB in order to construct the UV LED PCB lightbox project….?
Circuit and PCB
Thank you for your answer, but I meant a PCB that was already produced or was the intention for constructors to produce their own from the art work ?
i’m making one with a plastic storage box, the type you see on walls in shops. would it actually work better to put the LEDs hexagonaly?
thanks very much
james waples (13)
I think there is nothing wrong to put LEDS hexagonal or in other shape. Main thing is to keep light uniform as possible for smooth exposure. I don’t if this would give better results as this also depends on distance from PCB to LEDs, exposure time. You should give a try 🙂
the links for pcb and circuit are not working from were can i find them?
what box can i use and what are the required dimentions?
Thanks in Advance
Links are fixed now. Thanks.
I made this proyect myself bu I struggled finding a proper box for it. Finally I come across a 1.6L plastic box from http://www.reallyusefulboxes.com/.
The PCB fits nicely and the dimensions are just perfect for it.
If anybody wants to have a look at the finished proyect I took some pictures and uploaded them to http://freespace.virgin.net/big.jesus/index.html
All the merit goes to the original authors at RaDiKalDeSiG.
I want to make a PCB exposing Box using from UV LED’S.
there for can we use Normal Whitte LED’s to do it?
Please reply answer to my question..
I have a small new UV PCB light box to sell (London UK)
How much is it?
How to ship to sri lanka from UK? by the way i want to know other one question..
Normal copper clad board can we use to uv exposing? If not have a special copper clad board to do it?
Is the light box still available?
I was made from this site uv box http://www.qubbeks.puslapiai.lt/readarticle.php?article_id=25 but it dont using UV LEDs. Exposing time are about only 6min.