This paper proposes and demonstrates novel types of vision chips that utilize pulse trains for image processing. Two types of chips were designed using 1.2 µm double-metal double-poly CMOS process; one is based on a pulse width modulation (PWM) and the other is based on a pulse frequency modulation (PFM). In both chips the interaction between the pixels… (More)
This paper describes a retinal prosthetic device using a pulse frequency modulation (PFM) based photosensor with a standard CMOS technology and its modification to stimulate retinal cells effectively. A 32x32-pixel PFM photosensor array chip have been fabricated using 0.6 μm CMOS technology and demonstrated the improved functions.