Because PC, desktop computer and many keyboards need to be strictly tested, for keyboards that do not meet the accuracy range, they often affect the user's hand feel to a great extent, thus affecting sales. Because the detection of keyboards needs to detect their smoothness, so the use of 3D detection to meet user's needs. Please.
Detection requirements: detect the surface roughness of chocolate keyboard, the accuracy is 0.1mm
Inspection Principle - 3D laser triangulation
Laser reflection occurs on the surface of the object. At another angle, laser reflection or scattered light is focused by imaging system. The position of the spot produced by laser irradiation on the measured object changes, and the angle of light reflection also changes. Optical system is used to collect light. The spot is imaged on a CCD or PSD position sensor. The incident and reflected light form a triangle (as shown in the figure below). The coordinates of all points of the current scanning line are calculated from the images captured in the CCD. The 3D contour image is formed by combining all the points in the scanning process.
1. The Z-axis accuracy is related to the smoothness and reflectivity of the keyboard surface. Taking the Lingyue Ins15MR-7528SS series of Dell Computer as an example, the detection range is shown in the right figure. The Z-axis (height) accuracy can reach 0.05mm.
2. Y axis detection, taking 12cm wide case as an example, the accuracy is 0.06mm
3. The accuracy of X-axis detection is related to the detection speed. Under the condition of accuracy of 0.1 mm, the maximum speed can reach 500 mm/s (30 m/min).