Optical measuring system for inner surface dimensions of deep hole

As the requirement of the inner surface dimensions test precision of the deep-holed work pieces is very high, but either the resolving power or the efficiency of the measuring methods is low at present. So the optical measuring system for the inner surface dimensions of the deep hole is researched. The system is made up of a ring laser generator, a diffusing taper reflector, a gathering taper reflector and a CCD camera. When the ring laser emitted by the ring laser generator is projected onto the taper reflector, it is reflected to the inner surface of the deep hole and a ring facula is formed there. The shape of the facula reflects the profile of the inner surface of the deep hole. Then it is reflected by the diffusing taper reflector and forms an image on the CCD camera. With this image, the inner surface dimensions can be measured. The experiments prove that the system can measure the profile dimensions of the inner surface effectively and ensure high test precision. The precision can be advanced more if the error factors are ameliorated and the methods to compensate the errors are adopted.