A 0.5° Error 10 mW CMOS Image Sensor-Based Gaze Estimation Processor

A CMOS image sensor (CIS)-based gaze estimation processor (GEP) is proposed for the next-generation user interface (UI) of the smart glasses. It integrates a functional CIS, a RISC, and an ellipse fitting engine (EFE) on a single chip to reduce the power consumption. The functional CIS includes mixed-signal preprocessing circuits, pupil edge detection circuit (PEDC), and glint corner detection circuit (GCDC). Logarithmic processing element (LPE) is adopted in EFE to reduce the power consumption further. As a result, PEDC/GCDC and LPE can reduce the overall power consumption by 55.2% and 14.1%, respectively. Implemented in 65 nm CMOS technology, the 11.29 mm
²
chip consumes 10 mW power at 30 fps real-time operation, and 0.5° error is achieved in experiments.