Speed ??speed sensor is measured and the measured object can be transformed into a sensor output signal. Speed ??sensor including measuring line speed sensors and measuring the revolution speed sensor. With the development of technology, the traditional measurement devices can not meet the needs of the status quo, has gradually been eliminated, and laser speed sensor has been widely used, is of great significance in the production process, by connecting it to the computer can be automated test substance, intelligent measurement and control. This is now measuring technology and computer technology combined with the product.