Optical mark reader (referred to as OMR) is a special computer input device that can quickly identify the content of information scrawled on the card, and pass in the computer processing. Its basic principle is that light emitted by light emitting devices in the information card information bits, such as the information bit is partly blacked out light is absorbed and reflected light is weak, otherwise the reflected light to strong, from the corresponding receiving tube will strength of different optical signals to electrical signal transfer, and then the A / D conversion, digital filtering, pattern recognition card information after the completion of character recognition. 
 OMR data processing applications and combine to become a complete fast data processing system. With OMR technology continues to improve and OMR application the depth of the development, OMR areas get more and more recognition and praise. Up to now, OMR has been widely used in education, health, finance, labor, personnel, civil affairs, organization, justice, energy, telecommunications, transportation, and many other fields, has become the first choice for large data-processing equipment.