Many friends often don’t know some concepts when buying optical screening machines and other visual inspection equipment, which leads to dissatisfaction with the optical screening machines they bought. Here, the engineer editor of Maixunwei Vision Company will explain in detail and in-depth doubts. these questions

First of all, let’s talk about the pass rate of the optical screening machine, which is the yield rate: if 10,000 pieces are supplied this time, if these 10,000 pieces are undisputed good products, such as measuring the length, the length is within 10MM~20MM. It is a good product. The size of these 10,000 materials is 15MM, and the pass rate and yield rate can reach 100%. If the actual length of the 10,000 materials is 10.001MM, although it is also a good product, the qualification rate will become relatively low. , Why is it so? From several perspectives, we all know that the optical screening machine would rather kill by mistake than miss it. Assuming that the detection accuracy resolution of the optical screening machine is 0.01MM, this will lead to some 10.001MM materials as defective products. Of course When we process parts, we generally do not make the accuracy of the workpiece just near the lower limit.

When many friends order optical screening machines, especially users who do defect detection, they often unilaterally require the yield or pass rate to be above 90%. In fact, the manufacturers of optical screening machines can do it sometimes, and sometimes they do it again. No, what factors do it depend on? Let me give you another example. If the difference between defective products and good products is obvious, 100 quality inspectors can point out the defective or good products without hesitation. In this case, the pass rate of the optical screening machine can be achieved. It will be very high. If some of the 100 people think it is good and some others think it is defective, it will take a long time to distinguish the workpiece. In this case, the pass rate of the optical screening machine cannot be guaranteed. In summary , Users and friends must ensure that the pass rate of optical screening machine manufacturers must reach 90% or more. This requires a premise that all the materials tested must have obvious differences between good and defective products.