Project 136: Thermal Imager Project Update 13: TFT Screen

by PhoenixGames on Oct.02, 2015, under Inventions, Tutorials

I have wired up the Adafruit TFT Screen to my Thermal Imager project. I am pleasantly surprised at the quality of it, it is working very well.

I also took some pictures outside, but I could only display them on the screen since I haven’t implemented saving to an SD card yet.

Other than the SD card storage, the only remaining goals will be to add a status RGB LED to the project, and build the housing, as well as some debugging.

I don’t think I will be able to implement video, at least not at the moment. The screen takes quite a lot of time to refresh, and I am not sure if the Due would be powerful enough to handle even slow video.

I am still having an issue with taking thermal images reliably. I have had to modify my code to take a picture on start up, then print it to the serial port and the screen, and stop the program. This means that I have to press the reset button (restarting the Arduino) every time I want to take a picture. This is obviously not ideal, but when I tried to add a loop and a button, even using an interrupt, the lepton lost sync and stopped returning data. This is the only way that I can find so far to reliably generate images most of the time.

These are pictures of a glass of hot water. The first image has interpolation on, the second has it turned off. I actually think the image looks better with interpolation off, in this example at least.

These images were taken at least 75-100 meters away from my house. The image quality isn’t the best, since it is a picture I took with my mobile phone of the screen of the thermal imager, however, it is possible to see a reasonably clear outline of the house, and driveway, with a blue haze over it. This was taken in quite heavy fog, which is presumably what the haze is. I am looking forward to see what the high res image of this would look like on a computer screen, once I wire up the SD card, I will know.