Broadband Achromatic Reflective Metalens

• Main Authors: Shen-Hung Lu, 呂昇鴻
• Other Authors: 管傑雄
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/3nxgh4

碩士 === 國立臺灣大學 === 電子工程學研究所 === 105 === Conventional achromatic lens is made of many materials with different refractive index. It’s heavy and bulky. Recently, subwavelength structure can control the light phenomenon and phase which is called metamaterial. To compare with conventional lens, it’s light and thin. In this article, we made a broadband achromatic reflective metalens(BAML). We chose the material Au-SiO2-Au to be our sandwich-like structure because gold is high reflective material in the near infrared region(1200nm-1680nm). Then we present an optimized formula of phase compensation. With CST simulation, we define a new structure operated in the region which phase changes linearly. The structure called integrated-resonant structure is the unit element of BAML. The device is expected to focus the incident light with different wavelength on the the same focal length. If we successfully realize the concept, we can solve the problem of conventional lenses.