In this paper a reading method of dial instruments using a camera instead of human eyes is presented. This method uses an industrial camera as the detector and a computer as its central processing unit. The graphic data of the dial plate is taken with the camera and is input through graphic card into the computer where it is calculated recognized and logic treated and finally gives out the readout value. This method is characterized by rapidity high accuraccy easy operation and relatively high level of intelligence and automation. Measuring systems bsaed on this principle have been successfully applied to the intelligent verification of dial indicators.