2022-12-25 12:31 PM
Hello,
I have a problem with VL53L3 sensor measurements. When sunlight hits the sensor, the measurement is distorted, and the measured distance becomes small. Are there any settings for the sensor to remove this glitch when the sun's rays hit?
Solved! Go to Solution.
2023-01-10 09:17 AM
Hello
This is explained by the fact that the photons the sensor emits are not marked in any way save that they are at 940nm. So there is a band pass optical filter on the Receive side to eliminate all the other photons.
But the sun emits a lot of 940nm light.
At the beginning of the range, we take a measure of the 940nm light. This is the Ambient that you can get after the range.
What we are looking for is that signal over ambient.
But if the Single Photon Avalanche Diode (SPAD) array is fully saturated by the sun, there is nothing we can do.
But generally at the closer distances, the target obscures some of the sunlight and we can get a range. Also direction is important. Sunlight passing at 90 degrees to the sensor and the target has less effect on the sensor.
All this taken together means that a sensor that can range to several meters indoors, will be limited to maybe a half meter in bright sunlight.
But the good news is that if there is a returned value, it will be right. The sunlight stops the ability of the sensor to work, but does not corrupt the answer if there is one.
If you want to reduce the glitches it is recommanded to increase the sampling period to decreases noise but it also reduces the effective max convergence time and increases power consumption.
Hope it helps,
Anne
2023-01-10 09:17 AM
Hello
This is explained by the fact that the photons the sensor emits are not marked in any way save that they are at 940nm. So there is a band pass optical filter on the Receive side to eliminate all the other photons.
But the sun emits a lot of 940nm light.
At the beginning of the range, we take a measure of the 940nm light. This is the Ambient that you can get after the range.
What we are looking for is that signal over ambient.
But if the Single Photon Avalanche Diode (SPAD) array is fully saturated by the sun, there is nothing we can do.
But generally at the closer distances, the target obscures some of the sunlight and we can get a range. Also direction is important. Sunlight passing at 90 degrees to the sensor and the target has less effect on the sensor.
All this taken together means that a sensor that can range to several meters indoors, will be limited to maybe a half meter in bright sunlight.
But the good news is that if there is a returned value, it will be right. The sunlight stops the ability of the sensor to work, but does not corrupt the answer if there is one.
If you want to reduce the glitches it is recommanded to increase the sampling period to decreases noise but it also reduces the effective max convergence time and increases power consumption.
Hope it helps,
Anne