Frequency response test for thermal imaging sensor

I am testing the frequency response of the TPS334 IR sensor. My very crude tests agree with the datasheet, which means that the image scan time will be very long for high contrast images. Many low-cost microbolometer-based thermal imaging cameras have 80x80 sensors (6400 pixels). At a 10Hz pixel clock (-3dB sensitivity from datasheet), the frame scan time would be 640 seconds, or nearly 11 minutes. Yikes! At 100Hz, the sensor would only produce an output level of %10 of its DC capability, and still require just over a minute to scan the whole frame. Obviously, this will not be a "live video" system, but might still produce some interesting still image thermographs.

I am working on other methods of sensing long-wave IR too. More later.

Extech IR250 infrared thermometer disassembly and plans for thermal imaging

One of my ongoing projects is to develop a low-cost thermal imaging camera. In this video, I take apart an Extech IR250 infrared thermometer with the intention of grabbing an analog or digital signal so that I can record temperature measurements while using a scanning or image processing device to select portions of the scene being examined. Unfortunately, it looks like the analog circuitry is completely sealed inside a custom IC that is hidden under a blob of potting material. I'll remove the IR sensor from the board and build my own analog amplification and digitization hardware.






Common digital output IR thermometer sensor:
http://www.melexis.com/Infrared-Thermometer-Sensors/Infrared-Thermometer-Sensors/MLX90614-615.aspx

TPS334 sensor datasheet:
http://www.datasheetcatalog.org/datasheet/perkinelmer/TPS334.pdf

Analog Devices app note regarding thermopile sensors:
http://www.analog.com/en/all-operational-amplifiers-op-amps/operational-amplifiers-op-amps/products/technical-articles/using_thermopile_sensor_in_ir_digital_thermometers/resources/fca.html


Servo pan/tilt IR imaging scanner project:
http://www.cheap-thermocam.tk/

Redshift thermal imaging:
http://redshiftsystems.com/site