Along with the development of four-wheel positioning technology, a variety of high-tech four-wheel rode out, many manufacturers to catch up with the trend of the market, will be many low-end products as high-tech products, in order to trick customers. Common way of four-wheel testing on the market at present basically has: laser, PSD, CCD and 3 d. To ensure the customer can buy a real performance excellence four-wheel, will now laser, PSD, CCD, and are there advantages to using 3 d product, analysis is as follows:

Laser:

Laser is a new type of light source, it is as the light source is applied to four-wheel measurement system, due to the laser output is based on a vertical straight line, thus determines the range of the laser beam of products is relatively narrow, without compensation and artificial calculation thrust line, the measuring accuracy is low, slow speed detection. Because of the light spot and the relationship between the scale, there is human error, and laser is vulnerable to interference, so do with laser light source is applied to four-wheel is not ideal.