Optical System Design Of Ultraviolet LED Curing

UV LED is a new technology with the rise of LED,ultraviolet LED has the advantages of energy saving,environmental protection,long life,open or closed at any time,compared with the traditional light source those like high-pressure mercury lamp and metal halide lamp.Curing field is one of the main applications,such as printing,ink curing,UV and other industries,the traditional light source will be replace quickly with the UV LED technology matures.Currently,Most of the UV LED devices on the market using the LED rectangular array,each lamp is directly irradiated on the curing surface,which leads to the lamp of the spot formed and surrounding beads formed spot overlap,middle curing region of high light intensity,edge region low intensity.The energy utilization rate is low,the uniformity is poor,and the uniformity is serious when the working distance is slightly deviated from the fixed working distance,In this paper,in order to obtain the LED curing required rectangular beam,solve the problem of low light efficiency,poor uniformity and low radiation intensity is,UV curing optical LED system was designed.the core content of this paper is mainly the following two parts.First,an optical system for array UV-LED curing area-focusing is constructed,Based on the of geometrical optics and the Fresnel's law,the derivation of lens contour is completed,and the optimum resolution of lens array is calculated.The results show that the light is controlled effectively by lens,the irradiance intensity and irradiance uniformity of area-focusing is improved,while the structure of array is more compact.The uniformity is 95.3% and 98.6%,the irradiance intensity is 2.5 times and 6.4 times larger than Lambertian optical source array,when the half value of the light source is 27.5o and 15.5o respectively.Second,The Paper proposes a design of ultra violet LED curing line-focusing lens with combined lens and an optical system for spatial array UV-LED curing area-focusing is constructed,the simulations for optical system is constructed with the tracepro software.Experimental results show that the elongated rectangular spot obtained by single lens and its horizontal and vertical uniformity is 96.7and 98%,while the system's efficiency is 60%;The rectangular spot is obtained by area-focusing optical system,the optical efficiency is 66.46%,and its horizontal and vertical uniformity is 97% and 98.6%.