Is there a formula for the distance an infrared sensor "senses"? I'm making a Raspberry Pi-based infrared sensor for a school research project. Here's the link for the infrared sensor that is attached to the Raspberry Pi. At the moment, I don't have much quantitative data, and I need more.
My idea was to figure out the distance that the infrared sensor is "seeing" the passing object from. For context, the infrared sensor is remaining stationary, while the passing object is moving side to side and back and forth.
I looked into this topic, and I found a website that said you can use a formula to determine the distance in centimeters that the infrared sensor is detecting the object from.
However, when I looked more into this online, I couldn't find any other source mentioning this formula. Maybe I didn't look far enough?
If any more information is needed, I'd be happy to give whatever you guys need. Please note that I have barely any physics experience, and that the majority of the project is based in computer science.
Thank you!
 A: The part that you think you need:

Radar energy expands during both the signal transmission and the reflected return, so the inverse square for both paths means that the radar will receive energy according to the inverse fourth power of the range

https://en.m.wikipedia.org/wiki/Inverse-square_law
Also need to account for object's IR reflectivity. >0.95 for metals, for other materials could take about 0.5.
Need to account for object's size. Bigger it is, more light will be returned.
And some constant that you will need to find in experiments, to figure out how intensity of the light translates towards intensity of the signal on sensor.
So, something like this:
distance = (constant * size * reflectance) ^ 0.25
Part that you actually need:
Sensor you showed doesnt even output signal strength. Just on\off, so it cant measure distance.
And because of reflectivity, size and even angle the object is turned, all change the returned signal, such sensor type cant be used for even approx distance detection.
And its not even a single sensor, its a camera sort of thing, with several pixels, two in this case. And measuring 4th power from data from several pixels is just not going to be useful. And you cant even hack it to get the raw data anyway, and this pixel array just makes it all more complicated.
And 'distance' setting is just an intensity setting in this case, you cant detect distance by changing that turning resistor either. It will just change how big of an object it detects at which distance. Big ang close or small and far.
If you want to finish the project in under a year, pick a sensor that provides the data you want to receive. Hacking a sensor to get the data that it doesnt output is no easy task. And mention of Arduino implies you want a quick result.
