Abstract
With the advantages of low cost, small volume, low energy consumption, long service life and environment friendly, the application of UV-LED has attract widespread concern among academia and industry researchers, especially in the field of ink printing industry. However, how to get high power density in specific distance working plane is a technical problem need to be solved eagerly. This paper presents a design solution to reduce the Etendue of the lighting system and therefore obtain high power density. The design uses UV-LED array as the light source, and uses a freeform surface collimating lens array to collimate this light source. In order to improve the energy sufficiency of the system, multipoint fitting-based freeform surface lens design for UV-LED extended sources is proposed to design collimating free-form lens for UV-LED extended source in this work. The freeform surface collimating lens array is placed in front of the UV-LED extended sources array. And an aspherical lens is used in the optical path to focus the light beam. In the simulation, a light source module with the size of 9mm * 26mm has been designed, and obtained power density up to 8W/cm(2) in the specific working plane with the working-distance of 3cm. This design is expected to replace the existing mercury lamped-based UV light sources and solve the problem in the application of UV-LED ink printing field.