Fundamentals of 3D Line Laser Profile Sensors
The 3D line laser profile sensor adopts the principle of laser triangulation. First, a laser beam is used to irradiate the surface of the object to be measured, and the reflected light forms a spot on the surface of the photosensitive element through the optical lens group.
As shown in the figure below, when the detected surface is too high, the measurement laser spot position will move to the right; on the contrary, if the detected surface is lower, the measurement laser spot position will move to the left. The 3D line laser profile sensor uses not a point laser light source, but a laser line, and the measuring light laser spot is also a line, so it is commonly called a line laser. Line lasers can also area scan to quickly form 3D contours.
The basic principle of the general laser displacement sensor is optical triangulation: the semiconductor laser ① is focused by the lens ② to the object to be measured ⑥. The reflected light is collected by the lens ③ and projected onto the CMOS array ④; the signal processor ⑤ calculates the position of the light spot on the array ④ through a trigonometric function to obtain the distance from the object.