Key Technology Research On UV Curing Source With LED Array

UV curing becomes the most extensive radiation curing technology these days. This technology has been one of the main emphases in surface processing research all over the world, for what a great number of novel UV materials appear with excellent quality. In spite of that, the development of UV curing sources which affects the curing effect as UV materials is relatively slow, and serious shortcomings of several common UV curing sources have arisen in the industry application: high-pressure mercury lamp has many disadvantages such as high-pressure driven, cooling instrument needed, large power dissipation, uneven UV radiation, poor controllability, low curing efficiency, and heavy metal pollution; microwave UV source is high cost and its light structure as high-pressure mercury lamp limits the application; a kind of point source with UV LED has many adaptive characteristics although its radiation area doesn't meet some common demands. This thesis surveys the application condition of common UV curing sources and conducts an exploratory design on UV curing source with LED array, which will offer even, stable UV radiation and good controllability. A UV source system with 3*3 LED array is realized to verify the feasibility of the design.In the drive part, multipath controllable constant current source based on AT89S52 is adopted, so each branch current can be controlled independently by the keys in two modes, which give attention to several UV materials and different base figures with coarse adjustment and fine adjustment; Optical design combines single LED's collimation system and LED spatial structure. LEDs assigned on the arc board compose the spatial structure, in which the radiation of LEDs on same arc line converges at the axis and a facula is available for curing. Radiation area and intensity are controlled by changing the number and drive current of LEDs. Different from other UV sources, optical power density on the curing object can be adjusted easily and flexibly, which make curing for 3D object come true.On basis of design, the thesis conducts a series of experiments to verify the method using a system with 3*3 LED array, containing precision and stability of drive part and controllability and uniformity of the UV source. The results prove that drive part and optical system meet the design demand, and this UV source shows good stability, uniformity and controllability.