The laser displacement sensor has actually been introduced in previous issues, so why do we need to introduce it again this time? Because recently we met a customer who was asking us which sensor Lanbao has that can detect the thickness and flatness of the object surface. We I also learned that this customer was engaged in gluing, which is to apply a layer of glue to the surface of transparent objects, just like the common mobile phone films in daily life. I believe everyone is familiar with mobile phone film, but that thin film is not simple. There is actually a thin layer of glue on its adhesive surface, and it is through this thin layer of glue that the mobile phone film is adhered to the mobile phone screen. You can imagine what will happen if the layer of glue on the mobile phone film is applied unevenly. In order to solve this similar problem, this customer came to Lanbao and asked us to solve this problem for him. We introduced the new PTM laser displacement sensor to him in detail.

Our laser displacement sensor emits a laser beam at a certain angle based on a laser diode emitter. When it encounters an object, the beam will be reflected back. The laser spots on the light targets at different distances will be imaged at different positions on the CMOS detector. According to the position of the light spots on the CMOS, the distance from the light target to the sensor can be inferred. As shown in the figure below: It is known that the angle between the emission direction of the laser transmitting module and the optical axis of the receiving module is a, the distance from the center of the transmitting module to the center of the receiving module is x, and the focal length of the receiving module lens is f. According to the relative light spot on the CMOS detector The offset L from the reference point can be used to calculate the distance D between the light target and the sensor.

Through such a working principle and the highest resolution of 0.1um and the highest repeatability of ±0.5um, the thickness and flatness of the object surface can be well detected, and the measurement range of our displacement sensor is 10mm-200mm; Moreover, our displacement sensors are intelligent, sturdy, and convenient, and have surpassed other types of laser displacement sensors.