Using the Lumen for UV and IR LEDs

I’m interested in adding UV and IR lights to the BlueROV. I was thinking of finding a suitable LED (UV and IR versions) that can replace the Lumen LED and that can work with Lumen’s PCB. Has anyone here tried something like this before? Another option is using just the Lumen body and installing UV LED + driver. Thanks.

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Hi Oded! I designed a UV version of the Lumen a couple of years ago. It uses four smaller LEDs in parallel. It was designed for this LED but there are a lot in this form factor:

Below are the design files in Eagle (original and UV version) and you could replace the LED PCB on a Lumen quite easily. The important thing to remember is that the Lumen is a constant current driver set to run up to 2 amps. The LEDs have to be able to handle 2 amps total or they could burn out. You could adjust the firmware to reduce current or send a limited signal range.


Hey Rusty,
That’s great! thanks so much for that info. We’ll check it out and let you know how it worked out.

I tried this a couple of years ago and, while I cannot comment on IR, the UV conversion was unsuccessful. The main problem is the Lumen lens is acrylic which is UV impermeable, there are versions of acrylic which are UV transmitting (UVT) but this doesn’t seem to be a feature of the Lumen lens.

Secondly, UV LED’s require a lot more power to produce a similar output to visible light LED’s, in essence, either more LED’s or bigger, higher current LED’s. As a by-product of this, you end up generating a lot of heat.

The project I was working on was a crack detection camera. To deal with the heat problem I mounted the LED’s on an aluminium PCB, in the end, I chose some LED’s which simply wouldn’t work (for long!) at full power on an FR4 PCB.

The next issue was EMI coming from the LED’s and driver circuit which interfered with the camera electronics. To get round this, I had to design a dual channel, low-EMI driver from scratch. Dual Channel because the spec called for visible light too.

UV light doesn’t go very far underwater so don’t plan on lighting up a large area. The camera was designed to work at 100mm from its subject so, in my case, everything worked fine.

Finally, people seem to be astonishingly relaxed about things they can’t see - especially UV, so…


Two of the LED ring PCB’s and the the dual channel driver. I forgot the scale ruler in the pic but for reference, the LED rings have a 74mm OD.

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Thanks @Sarawak_ROV for the info, I wasn’t aware about the fact that acrylic is blocking UV, that’s an important point. We didn’t have the chance to dig into that yet but will do hopefully soon and share our results.
And thanks for the safety tip too!

On this point, it’s also worth noting that water itself will quite strongly absorb both UV and IR light:

Source: Wikipedia - Electromagnetic absorption by water

I’m keen to see how your testing goes :slight_smile:

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