Sensitivity to disk vibration and large component number, which complicates assembly and optical alignment, are the drawbacks of traditional optical pickup systems. Here, a numerical method of designing a dual-wavelength diffractive objective lens with high numerical aperture for generating arbitrarily discrete, diffractionless beams with extended depth of focus is presented. Simulation and experimental results show that the optimized design provides better resolution, longer depth of focus and higher diffractive efficiency.
View Article and Find Full Text PDFA color-separation system that angularly positions color LEDs to produce color separation and a lens array to focus this light onto the pixels is proposed. The LED rays from different incident angles are mapped into corresponding sub-pixel positions to efficiently display color image, which can be used to replace the absorbing color filter in the conventional liquid crystal layer. In this paper, the prototype backlight has been designed, fabricated and characterized.
View Article and Find Full Text PDFA diffractive grating is promising for color separation to effectively replace conventional absorptive dye color filter in liquid crystal displays. In this paper, we demonstrated a color separation module consisting of an aspheric-lenticular lens array and a blazed grating to substitute for the dye color filter. Each component was designed to match the recent fabrication ability of our roll-to-roll imprinting.
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