Light modulator using total internal reflection at an interface with a tunable conductive layer

US10197793B2 · kind B2 · utility

Assignee

• The Chinese University of Hong Kong · CN

Inventors

• Xudong Liu · Yongcheng, CN
• Zefeng Chen · Shantou, CN
• Edward Philip John Parrott · Kowloon, CN
• Benjamin Ung · Evandale, AU
• Jianbin Xu · Beijing, CN
• Emma MacPherson · Hong Kong, CN

Key dates

• Filing date: May 8, 2017
• Grant date: Feb 5, 2019
• Expiry date: May 8, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01Q15/0006
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A light modulator (e.g., for terahertz radiation) may be constructed using a prism in which light undergoes total internal reflection (TIR) at one surface. A tunable conductive layer is disposed on the TIR surface. The tunable conductive layer can have a conductivity that is dynamically controllable, e.g., by applying a voltage across the tunable conductive layer or by optically pumping the tunable conductive layer. The tunable conductive layer can absorb a portion of the reflected light beam, attenuating the beam, with the attenuation being a function of the electrical conductivity of the tunable conductive layer. The phase of the reflected light beam can also be altered as a function of electrical conductivity of the tunable conductive layer.