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Comment by dTal | Hacker News Reader

Nice build, but the night vision goggles I've always wanted use either light amplification (like in Jurassic Park) or thermal imaging. You're not likely to build those for $100, but that's why this seemed an interesting click. Infrared LEDs plus a near infrared camera is rather humdrum (it's built into my laptop for instance) and can be built for far less than $100, albeit with a bit less polish.

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You can get a FLIR Lepton 3 thermal sensor for about $150-180 used, typically in the form of an older FLIR One 2nd Gen iOS/Android dongle (eBay).

160x120 resolution isn't great (320x240 is generally the "good enough for casual night imaging" resolution), but those are the best you can do before stepping up to a minimum of $500+ per image sensor (seek compact pro).

Here's an image set of a cat walking around a fenced-in deck next to a tree: https://imgur.com/a/WmuQ1lA

If you look carefully in one image, you can see the heat from the paw prints remaining visible as a line in the grass. You can't see the actual prints at that resolution, but the sensor is absolutely good enough to see trails like that, especially indoors with footprints.

And in terms of intensifier tubes, you can do reasonably well picking up one of the Gen 1 monoculars sold all over the place, somewhere around $150-200 per eye, though you have to be careful as some of them are better than others.

Yeah if you've ever used proper thermal cameras, "not great" is an understatement. Plus I assume they are limited to 9 FPS which sucks.

Someone really needs to challenge FLIR's monopoly.

The Lepton modules you can buy are limited to 9fps, yes. They do seem to make some that are higher frame rate, but they aren't advertised anywhere.

FLIR and other companies like Seek[1] are selling 15/30fps imagers that are not much more expensive, though not in modules for DIY use.

The Seek Compact Pro[2][3] does a pretty good job for the ~$500 price tag

[1] https://support.thermal.com/hc/en-us/articles/208377803-What...

[2] https://www.youtube.com/watch?v=Rgyr-4u06FU

[3] https://www.youtube.com/watch?v=ybDpuFecruM

In case anyone was looking for it, the parts list was in the comments. The optics are a $25 module made specifically for the Raspberry Pi.

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    Headset: "Yuneec SkyView FPV HDMI Headset For Use With HDMI Compatible Devices" ... Currently $69.99. Price was $39.99 when I bought it. https://www.amazon.com/dp/B01K37O1BS/ref=cm_sw_r_cp_apa_2W3ABb2582724

    Camera/LEDs: "Raspberry Pi Zero Camera Fisheye Wide Angle 5MP 1080p Night Vision Camera Module for Raspberry Pi Zero W" https://www.amazon.com/dp/B074DY544H/ref=cm_sw_r_cp_apa_X43ABb4075B84 $24.99

    Micro-HDMI male to Mini-HDMI male cable (I couldn't find this exact cable in a short length so I used a mini to mini 6 inch cable with a micro to mini adapter)

    raspberry pi zero

    Micro sd card

    on/off switch (I cut the raspi USB cable and ran it through the switch

    power pack (the one I used contained two 18650 lithium Ion batteries and a circuit board. I disassembled the unit and mounted the circuit board with the charging port facing through the HDMI port of the headset)

Agreed. The "night vision goggles" I've always wanted are a) a thermal imaging camera, and b) whatever it is the military means when they say "night vision goggles".

The military night vision systems are based on "image intensifier" tubes. Interesting thing about them is that they are still based on all-analog vacuum tube technology. Considering that, it is pretty amazing how well they work in practical sense.

The up- and downside of night vision (vs thermal vision) is that you are amplifying visible light, so what you see is mostly similar to what you would see with unaided in brighter ambient light.

> Interesting thing about them is that they are still based on all-analog vacuum tube technology.

Yep, as I understand it, at least the 2nd Gen tubes have a surface that turns incoming photons into electrons, then those electrons bounce around inside tiny "micro channels" with a high voltage applied to them, which causes more electrons to bounce down the tube. And then they hit a phosphor screen and turn back into photons.

It's really quite clever.

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