Incident light angle detection technique using polarization pixels

In this paper we present the design and analysis of a CMOS image sensor pixel capable of detecting the angle of incident light. Determining the angle is of paramount importance in reconstructing the 3D information of the imaged scene. These pixels achieve this by including polarization gratings on top of the photodiodes in each pixel. Three different pixels, each with different grating orientation produce enough information to determine the local incidence angle. Because of the symmetric nature of the response for positive and negative angles, another set of pixels, called the linear quadrature pixel cluster has been included to break the symmetry and provide greater angle resolution.We present the simulation results as well as the design, which is targeted towards GlobalFoundries 65 nm CMOS mixed-signal process.