People normally do this by scanning a 10mW 832nm laser with a mirror, according to Dan Gelbart in https://www.youtube.com/watch?v=0MtRxX0crjU. The lecture is 77 minutes, covering nonlinear junction detectors, digital calipers, the US-embassy bug in Russia, laser microphones bounced off windows, and geometric errors from material relaxation. The bit about camera detectors is close to the end. Works for eyeballs too.
Lensless sensors (for example, using compressed sensing, or Hadamard shadow masks) can presumably defeat this, but also, watching from far enough away should defeat it. Hard to do that inside a pervert's AirBNB, though.
kragen
Until someone develops hidden cameras with AI that will be auto turned on couple of hours later after detecting presence at that time a scan was already performed and nothing was found.....
carlostkd
If this worked with IR, and so non visible, it might be even more useful.
Great idea though.
fidotron
Can't a thermal camera can do this? It should be able to detect any difference in ambient temp, even a few degrees, and a CMOS sensor gets warm, not to mention any wireless transmitters, power sources, and ICs. Turn off everything in the room and walk around with a ~$100 ali express handheld thermal camera.
Eisenstein
I wonder if it works with smart glasses.
brunoborges
Cool, but we need that for microphones.
throwaway81523
Yeah I don’t think this will be effective, cameras can be put in certain angles that it can see with being seen, or how police do it, entirely behind clothes or similar fabric where it can see through and identify but not seen even if you’re looking straight at it.
comments (7)
Lensless sensors (for example, using compressed sensing, or Hadamard shadow masks) can presumably defeat this, but also, watching from far enough away should defeat it. Hard to do that inside a pervert's AirBNB, though.
kragen
carlostkd
Great idea though.
fidotron
Eisenstein
brunoborges
throwaway81523
tamimio