Three dimensional optical interconnection technology for neural networks

Three dimensional (3D) optical technologies based on the free space propagation offer potential advantages to the massively parallel systems over electronics from the view point of information transfer and direct image processing abilities. The purpose of this paper is to survey some aspects of the 3D optics for the optical implementation of neural networks. The state-of-art of the optical array devices, the optical architectures, examples of the optical neural networks are described.