System design of time-of-flight range camera for car park assist and backup application

Abstract

External sensing applications in automobiles are enabled by Microsystems that can sense and analyze 3D environment. In this paper, we describe the system design of a time-of-flight (TOF) 3D range camera for parking assist and backup application. The camera operates based on measuring the time delay of modulated infrared light from an active emitter, using a single detector chip fabricated on standard CMOS process. The system analysis approach involves a step-by-step process that maps the application requirements to a series of camera design decisions producing the specification for a camera solution that is optimized for size, cost, power and application performance. The analysis process uses the empirical and theoretical performance properties of a 3D TOF sensor and the camera optics. It defines the profile of an optimal light source that delivers the necessary depth resolution for the given volume of interest in the application.