According to the global wind energy council predicts that by 2030, global wind power will reach 2110 GW, accounting for 20% of total electricity supply. As a result, more efficient, reliable and longer life wind systems are needed. Relatively speaking, the wind motor fan belonging to vulnerable parts, often hundreds of thousands of euros in additional maintenance costs, therefore, the German Fraunhof Application Institute of solid state physics (IAF) a fan for the quality control of leaf material scanning detection device is developed. The device has three features: first, it can detect and identify defects in composite plastics. In the manufacture of fan blades, nearly one hundred layers of glass fibers are laminated in order, and the layers are bonded with epoxy resin. The difficulty of quality control is that the glass fiber layer should be kept smooth and smooth without any fluctuation before bonding. Infrared thermal imager can be used for large area surface inspection, and the device developed by IAF can be more accurate for deep detection, and can be used to detect the location of the ultrasound method is not applicable. Two is the cross section inspection precision reaches the millimeter level. The core of the material scanner is a high frequency radar operating at W and transmitting power at 85-100 GHz. The special software can process the transmitted and received signals as visual results, thus identifying the defects in the millimeter range of fan blade cross section, which is more accurate than the traditional method. The radar module uses InGaAs semiconductor technology, which is lightweight, compact, and has only the size of a cigarette box and can be measured over the internet. The future frequency range can also be extended to 260GHz, that is, to the H segment. Three is to reduce maintenance costs by shortening downtime. At present, it is mainly through expert percussion to judge whether the blade is damaged or not. With this automatic radar technique, the utility model can significantly reduce the downtime and save the expenses, and is especially suitable for the difficult and time-consuming marine wind power devices with manual maintenance. The radar scanner can also be used in the detection of new aircraft, such as Boeing 787 and Airbus A350, which employ lightweight composite materials. The technology will be on display at the 2017 Hannover industrial fair.