780nm compatible sensor for outdoor use

Using Arduino Sensors
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Hey all.

I have modified a broken GBB airsoft gun I have to work as a laser shooter instead of a BB shooter.

I have a 650nm red dot focused laser module running down through the fake plastic barrel jacket, and a simple 12mm LDR positioned behind a 3d printed box enclosure that has a white-ish piece of 2mm thick diffused panel about 4" in diameter in front of the LDR as my target box. The diffused panel allows the LDR to detect the red dot splash no matter where it hits on that panel.

Works great for indoor games, but now I want to try it out doors.

The current red dot laser won't work due to the sunlight, so I thought of using an IR laser instead.

I can get a cheap enough 780nm IR from ebay or Ali that I can swap out and fit into the plastic barrel easily enough, but I have a feeling the current LDR set-up isn't going to work outdoors with a 780nm.

Any suggestions?

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Lots of IR in sunlight!

The solution is to use modulated beams and receivers (usually around 38 kHz, as with IR remotes). LDRs are too slow to detect those signals.

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Had a feeling the LDRs would be a no go.

What am I looking for as an alternative?

Is something like a TCRT5000 or KY022 a possibility? Or even a small ESP32 style camera that is looking for the IR splash something?

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You might look into what people use for laser tag outdoors. There are DIY articles.

camera that is looking for the IR splash

Most cameras have IR filters, for color balance.

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Just found this DIY guide.

Looks interesting. When I googled the IR range of the mentioned TEPT5600 phototransistor, it states 570nm. That got me thinking that maybe I can swap that out for a version more suited to 780nm etc. I also wonder if they'll also work behind a wider diameter diffuser panel like the type I'm currently using. No harm in trying. Worth a punt.

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