I am interested in transparent materials (resins/glues) that are easy to apply, are fully submersible in salt water (20 - 30 cm depth), and have a refractive index (once hardened) as close to glass as possible. The cameras I need to waterproof weigh < 2 g and are similar in size to a smartphone camera. Thank you for any and all suggestions!
Hello Martha,
Will there be any feedthroughs for power or data to and from this intrepid cameras?
Optically clear resins are plentiful, and some have pleasingly glass-like refractive indexes:
Electrolube UR5640 comes to mind - I had to waterproof cameras and lidars for an aquatic robotic firm some years ago.
https://electrolube.com/product/ur5640-optically-clear-polyurethane-led-potting-compound/
Power and data are the problems. If you're potting the whole damned thing, that makes life a lot easier. I'd be inclined to have the forward-facing optics encased in a rigid resin, and then backfill the guts (power/data card) with a soft resin that you can excavate after its mission.
Something like dragonskin (theatrical makeup resin) or|
UR 5638:
https://www.macdermidalpha.com/sites/default/files/2022-09/UR5638-Encapsulation-Resins-EN-03Feb22-TB_0.pdf
What depths are you looking for these to work at?
Hi @James Garry, thank you so much for these ideas! Using two different resins definitely sounds like the way to go, and I'll check out your specific recommendations.
Yes, we will have power and data feedthroughs bundled together, leading to a Raspberry Pi or laptop. The wiring does need to remain quite flexible, as we want the animals to walk/swim freely around a large pool with the cameras on their backs. They will be at a depth of 20-30 cm at most (it's a shallow paddling pool).
'Morning Martha,
I should have added a little footnote - depending on the camera, another approach is to pot the camera but to leave the window/lens free.
Reason being, if you pot the lens as well, you've then got to;
a) cast a flat surface (not hard, but...)
b) account for the distortion of having a 1.45 index material - of differing thickness - infront of the lens.
I'd be inclined to pot the electronics, paint the epoxy up to the edge of the window/lens, and no further.
Might need some preparation of the lens/window - but that depends on the nature of the materials.
Can you share a pic/diagram of the camera itself?
- Badges
- Science topic