A Multimode Neuromorphic Vision Sensor With Improved Brightness Measurement Performance by Pulse Coding Method.

This paper proposes a multi-mode neuromorphic event-frame integrated vision sensor that enables event detection (ED) with simultaneous brightness measurement based on the pulse-width-modulation mechanism. The logarithmic voltage is directly taken as intensity information. Brightness measurement involves in-pixel voltage-to-pulse conversion and out-pixel pulse coding. The maximum event bandwidth is improved to 366 Meps by pipelining the time-prior arbiter along with the address-events grouping circuit. A wide intensity dynamic range of 105 dB can theoretically be achieved through logarithmic photoelectric conversion and pulse coding. Our sensor supports a 128× 64 frame-like image with an improved signal-to-noise ratio of 49 dB. The experimental results indicate that the log sensitivity of the optimized logarithmic photoreceptor was measured as 164mV/dec. The equivalent frame rate for both event and intensity reaches kilo fps, making it a promising candidate in high-speed wireless sensing applications.