Flir Lepton 3 for automotive use.

[Theo van Wessel]

Hi there,

Found this Google Groups on Flir Lepton 3 modules, because I'm busy brainstorming if this module can be used as a more affordable Flir PathfindIR alternative.
A local shop in drones and drone equipment sells the Flir Lepton 3 module as well as the Flytron "Drone Thermal" pcb with 12VDC input and PAL/NTSC output.
http://www.flytron.com/thermal-cameras/303-dronethermal-micro-uav-thermal-camera.html
I told them about my idea to use the Lepton 3 module and "Drone Thermal" pcb as an automotive thermal imager behind the grill of my car. But they told me that this module may not be suitable for this purpose. I can not understand, because this module is used on drones for long range thermal imaging from huge hights.

Some questions then:
1. Is the Flir Lepton 3 module realy not a good idea to use as thermal imager in a car, using the 7" TFT screen of a 2DIN head unit to see the picture?
2. When automotive use for the Lepton 3 is posible, even though the 160x120 pixels may be a bit low, will the image suffer from shocks when driving?
3. Is there a rugged and waterproof case available for the Lepton modules, or do people make their own from cheap action cams provided with IR lens?

[Marty Sullivan]

I don't see why you couldn't do this, as long as you aren't relying on it for life vs death. I think your biggest challenge is weather-proofing the Lepton. This is complicated by the fact that the lens cannot be obstructed by whatever method you encase it (saving the purchase of an expensive thermal lens). Also, a single droplet of water on the lens will obscure the entire scene, even if you somehow manage to weatherproof the rest of the Lepton and your microcontroller. 

[Theo van Wessel]

How should Flir solve this water droplet issue with their PathfindIR then?

Often I see that this camera is installed in the open, facing the weather.

[Marty Sullivan]

I'm not familiar with that product, but it looks like it has a special, much larger lens than the Lepton. In addition, it has a higher resolution and a good focal length. All of these things will reduce the impact of water on the lens much more than that of the Lepton. Water will still cause some trouble though, see this q/a:

http://www.flir.com/cvs/cores/knowledgebase/index.cfm?CFTREEITEMKEY=327&view=35844

[Theo van Wessel]

That's a clear explanation, because the bigger lens, higher resolution and in particular the focal length will reduce the influence of droplets.

In the mean time I found out, that if I should build a automotive camera with the Flir Lepton module, costs will come close to a complete Flir PathfindIR module.

The Lepton V3 with shutter, break-out board with PAL/NTSC out, custom made rugged/waterproof IP68 casing, and special thermal lens, will end in a high price.

Next to this a special lens heater will be needed to avoid moisture and ice, and this is a true hard issue regarding the temperature readings of the Lepton module.