photodiode-based distance sensor

Thread Starter

andreastrinna

Joined May 11, 2024
1
Hi, i'm now facing a problem with some wierd project i have to do in college. i'm building a distance detector using just a photodiore as my only sensor. the problem is my photodiode is giving me output that are extremely variable, and they often variate on their own even if nothing changes in the surrounding. do y'all have an idea of what can be the problem?
i'm using a classical fotoconductive configuration with the cathode at 5V and a 10k resistance to the ground
 

Sumama2263

Joined Jun 10, 2024
4
Instead of using only photodiode use an IR sensor which has a photodiode embedded in it. Simple IR sensor isn't gonna work here as it only gives 1's and 0's and will not give range of voltages. I would recommend IR sensor like this one.
 

MrAl

Joined Jun 17, 2014
11,734
Hi, i'm now facing a problem with some wierd project i have to do in college. i'm building a distance detector using just a photodiore as my only sensor. the problem is my photodiode is giving me output that are extremely variable, and they often variate on their own even if nothing changes in the surrounding. do y'all have an idea of what can be the problem?
i'm using a classical fotoconductive configuration with the cathode at 5V and a 10k resistance to the ground
You may have to filter out 60Hz or 50Hz noise that would come from ambient lighting in the room. It will actually be 120Hz or 100Hz though. Fluorescent lamps cause problems and so do incandescent bulbs. We don't see much change in the light output but it does change due to the line frequency sinusoidal waveform. It's enough to bother light detectors of various kinds.
 
Top