A review of active optical devices: I. Amplitude modulation

This article presents a review of active optical devices. We examine different technologies that can be used for active wavefront modulation in a large range of applications including displays, electronic paper and adaptive optics. We introduce this review by describing different light modulations that can be achieved, namely amplitude, phase or wavelength modulation. We then examine the different criteria used in order to assess the different technologies and we describe in detail each technology including the method of light modulation, its characteristics and its applications. This review is divided into two parts: the first one is devoted to amplitude modulation and the second to phase modulation. (topical review)