I think I get the concept of a machine sending pulses of light, the light bouncing back to a sensor and measuring that time delay (for speedometers and such). But how does it work with non reflective surfaces? How can the light speed be measured with tiny distances and short travel times? Or do I have it wrong and they’re really just cameras that only measure incoming light?
In: 8
Most of them use passive infra-red sensors. Read about them here (https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor/how-pirs-work
Latest Answers