I am planning to play around with different IR LEDs and sensors. Basically I want to emit different IR wave lengths through different samples (lets say a banana or any object) and measure on the other side the absorption with an appropriate sensor.
There are a lot of ~940nm IR LEDs commercially available and IR sensors like the popular TSL235R sensor (it's very cheap) that detects any light in the range of 300-1000nm. This is a good start, but I am actually looking for LEDs and sensors that can emit/detect in the range of 5-10 µm (mid-IR). I was not able to find any good LED/sensor pair that works at this range. So I am asking you guys if you know about any other cheap LEDs/sensors that I can test. Thanks.