I'm trying to figure out what this component is, circled in orange.

Electronic circuit showing component circled in orange

It's part of an evaporative humidifier (Canopy) and points through a plastic window to the water in the base. I'm guessing it's an optical component of some kind, but I've not seen one quite like it before, and it's labelled as an IC, which is throwing me off.

It appears to consist of two semi-circular disks connected together behind a window.

The large metal legs beside it dip into the water and I presume are used to detect if there is water present by measuring the resistance, so another sensor would seem redundant.

These are the components on the other side of the board, if it helps:

a picture of a circuit board

  • 1
    \$\begingroup\$ Looks an LED; if you can't see it in operation, it may still be IR. \$\endgroup\$
    – greybeard
    Commented Dec 20, 2022 at 18:49
  • 5
    \$\begingroup\$ Maybe a UVC LED to help prevent algae growth in the tank. \$\endgroup\$ Commented Dec 20, 2022 at 19:09
  • \$\begingroup\$ Maybe also add the text on the bottom. I think it’s a sensor. \$\endgroup\$
    – RemyHx
    Commented Dec 20, 2022 at 20:13
  • 2
    \$\begingroup\$ It's what Spehro said. Avoid eye and skin contact with the UV light from it. \$\endgroup\$
    – GodJihyo
    Commented Dec 20, 2022 at 20:14

1 Answer 1


I believe it's a UV-C LED that emits short wave ultraviolet light intended to prevent algae growth in the water tank.

UV-C is considered germicidal and can cause skin and eye damage, so you should avoid allowing the light to fall on any living part of your body.


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