Hello,
I am using a Garmin LIDAR-Lite v4 LED. I noticed that between a black bag and a white sheet placed flat against it, the measured distance can vary by about 10%, even though the actual distance to the object has not changed.
Is this normal sensor behavior? Can the type of target (material, texture, or color) influence the distance measurement?
For these tests, I used the example code provided by SparkFun.
Regards
Yes, yes…material type influences reflectance and the sensor works by measuring the amount of laser light reflected across “x” time…you could calibrate it for a gray color between, or normalize against the value differences you see
I could be wrong, but i don’t believe this sensor can detect an object placed directly on it. The light from the laser needs to come out of one side of the sensor, bounce off the object and go into the other side. With the object pressing against the sensor you’re not giving the laser a chance to reflect off the object.
Hi, yes, this is normal behavior for the Garmin LIDAR-Lite v4 and most optical distance sensors. The readings depend on how much light is reflected back, so the target’s color, material, texture, and surface finish all matter. Dark or absorbent surfaces like a black bag reflect less light than a white sheet, which can lead to weaker signals and noticeable variation in distance. You may find this related PCBWay project useful as a reference for LiDAR integration: ESP32-Based Wireless Smartwatch | LiDAR and WiFi Scanning - Share Project - PCBWay. For better consistency, try averaging multiple readings or adjusting the sensor’s acquisition and filtering settings.
Sounds like you have done just two tests: black bag +/- white cover.
It would be a good idea to repeat the test with a few different materials, with different surfaces, checking for measurement variation.