Silicone keyboard is one of the computer input devices. It is characterized by translucent, soft and deformable material, and the surface features are not on the same plane. How to completely and clearly capture the edge contours of the product surface features is the primary consideration in the inspection project.

Due to the special material of the silicone keyboard, the light will transmit light on the product. It is difficult to take a clear picture of the edge of the raised feature with a fixed-focus industrial lens, and the high-precision measurement requirements cannot be achieved. The telecentric industrial lens only receives parallel light, so the light refracted through the silica gel will not interfere with the imaging, and the measurement requirements can be well completed.

The key part of the silicone keyboard is raised, and the features of the product are not on the same plane and have a certain distance. Using a fixed-focus industrial lens, the front and rear raised features cannot be clearly focused at the same time, and cannot be completed at one time. The telecentric industrial lens has a large depth of field, and can focus clearly on different convex features in the front and rear of the sample at the same time, completing image acquisition at one time.

Since the raised features of the keyboard are not at the same object distance, when using a fixed-focus industrial lens to capture images, the magnification is different within a field of view, and the proportional relationship is inconsistent, so the measurement cannot be guaranteed to be the same accuracy. The telecentric industrial lens will not have different optical magnifications due to different object distances, so even if the characteristic object distances are different, the proportional relationship during measurement is constant and unique, which can ensure consistent measurement accuracy.

The Pomeas telecentric industrial lens has low distortion rate and large depth of field, which can well solve the problems of light transmission in the detection of silicone keyboards. And it also has good performance in glass bottle defect detection, reflective metal parts detection, precision parts size measurement and other projects.