Design, Fabrication and Measurement of Color Gratings

• Main Authors: WeiKo Wang, 王唯科
• Other Authors: MaoHong Lu
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/08704755588732269540

碩士 === 國立交通大學 === 光電工程所 === 89 === Both the gratings and filters are commonly used for separating light in the optics, but the efficiency of filters for separating light is generally not good. So the system with the filter needs more power of light in order to have enough light intensity. In this thesis we designed a color-grating, instead of the filter, to separate light. With the color-grating we can increase the efficiency to 80%. Since the line-width of the grating is same order of magnitude as the wavelength of light, instead of the simple scale diffraction theory, we have to use the rigorous coupled-wave theory (RCWT) for calculation of the grating efficiency. So an optimization program by the RCWT is made for determining the structure parameters of gratings and environment parameters, such as line-width, the depth, incident angle …etc. The line-width of our gratings is so small that we made them with E-beam lithography techniques. Finally, I would discuss and analyze the difference between the measurements and the calculations.