Focusing lens ω photoelectric detector photoelectric conversion polyhedral rotating mirror reflector receiver data processing system in Figure 2 laser scanning diameter measurement principle The picture shows to ensure measurement precision and reliability, optical scanning measurement system must meet the following three basic requirements: Laser The beam should be perpendicular to the radiation measured surface; beam surface of uniform linear scanning movement; (3) scan time must be measured very accurately. In reality, the scanning speed is not constant but varies with the angular displacement of the scanning rotating mirror changes, so will have a principle error. In summary, we can see, this method has its advantages were measured using a CCD. The selection of green laser pointer is based on the actual needs and real requirements.
But also unable to overcome its own shortcomings. Look at the use of laser scanning to measure the diameter of the method, such as scanning speed of less than uniform and principle error, but we can use different algorithms to reduce this part of the error. After the comparison, I decided to adopt the principle of laser scanning to measure diameter. The design idea of laser diameter measurement system device mainly by high-performance scanning optical system, mechanical structure and signal receiver  with the data processing system. The overall system block diagram shown in Figure 3. The design is principally engaged in the hardware circuit design, signal receiving and data processing systems and software architecture design and data algorithm approach -4 -. The customer can even use green laser pointer express his love to someone and so on.
Laser scanning workpiece shaping circuit amplifier pulse laser scanning receiver sub-circuit microcontroller sound and light shows the block diagram of the data signal oscillator 3 system. Program design based on the composition of the various parts of Figure 3 shows the total block diagram of the laser scanning system, and I, respectively from hardware, software and data processing part of the design. The following is made on the part of the design described. Part I: Hardware Design Hardware circuit design of the main amplifier circuit [9,10], the shaping circuit, crystal oscillator circuit and microcontroller circuits  of four parts, each part of its role as follows: 1) amplifier: the receiver to convert optical signals into electrical signals, and signal amplification. Especially the star green laser pointer is the very practical tool for the customer.