Appearance tester for electron parts is furnished with super hard guide for the purpose to form electron parts orderly ques to one direction. The guide is made of super hard material which arranges more than 10,000 parts per minute, scraping to form orderly ques toward one direction. Consequently, guide bitterly wears and requires frequent maintenance. If guide maintenance is ignored and if alignment arranged parts form lose their formation, smooth proceeding of the parts will be disturbed and it may lead to production line stop or become the cause of defective parts yielding.

As the material of guide of appearance tester, if super-high abrasion resistant DLC (Diamond Like Carbon) is coated to guide, the trouble can be prevented caused by the shape change of the guide by scraping. DLC is mainly made of carbon which is hard coat with the superior characteristic of being non-pollutant and of smoothness. If DLC is coated to super-high hard guide, it makes it possible to add characteristic of having high hardness and smoothness without losing surface roughness. If adapt this characteristic, durability of super-hardness becomes longer and can reduce maintenance cost without operation stop caused by guide shape change.