How Does an Automotive Rain-Sensing Wiper Work?

[MacFinn]

Currently, the two most widely used mainstream sensors are optical sensors and capacitive sensors. Below is the working principle of automotive rain-sensing wipers: 1. When the sensor detects rainwater falling on the windshield, it sends a command to the wiper to start working, and the rainwater on the front windshield is cleared. 2. The wiper is commanded to start working, and the rainwater on the front windshield is cleared. Here is additional information: 1. Optical sensors operate based on the principle of light refraction. An optical sensor contains a light-emitting diode that emits a conical beam of light, which passes through the front windshield. When the windshield is dry and free of rainwater, almost all the light is reflected back to an optical sensor. When it rains, rainwater accumulates on the windshield, causing some of the light to deviate. This results in a change in the total amount of light received by the sensor, thereby detecting the presence of rainwater. 2. The larger the area of reflected light that the optical sensor can receive, the more detailed the information obtained. Optical sensors are highly precise and can even accurately determine the number of raindrops falling on the sensing area.