1. A Time Error Correction Method Applied to High-Precision AER Asynchronous CMOS Image Sensor 李东盛

2. Introduction Low redundancy High time resolution No frame High DR Digital Time-domain Real-time visual sensory Intelligent Autonomous

3. Categories Light intensity change Tracking for high-speed particle Light intensity Video monitoring Color change Robotics vision EventAERProcess

4. Working principle of AER  Address Event Representation

5. Pixel structure  Two PDs  Three stages in CD  Reset control  EM

6. Pixel Array  Pixel → Row arbiter → Row address encoder → pixel → Column arbiter → Column address encoder → external → pixel  Because the time- stamping of the AER asynchronous image sensors is made in the external, so the time of making time-stamping is not the accurate time when the pixel generates pulse events.

7. The Arbiter

8. Time Error Analysis

9. T delay2

10. If the two events are in the different rows In Fig. 5T rowab T delay2 (a) (b) (c)

11. If the two events are in the same row In Fig 6 T colab T delay2 (a) (b) (c) (d)

12.  more than two pixels sending requests at the same time  When an event is being processed and some other events are waiting for being processed, another event occurs:

13. Time Error Analysis  Main factors  The complexity of the pixel array  The event rate  Processing speed of the external circuit  Error on image  The more the light intensity is, the worse the error on image is.

14. Correct method  Recording the time error from red to green can be achieved.

15. Pixel and pixel array with correction

17. Simulation in Matlab  All the simulation was based on the global reset mode.  Mainly based on an 8 × 8 pixel array.

18. Light intensity  Simulation condition:  All the pixels with the same input signal.  Speed: 100MHz

19. Collision events Number of collision events Without correctionWith correction Error range Average Error range Average 64 0.033%~7.933% 4.154%0. 033% 32 0.200%~4.100% 2.111%0~0.033%0. 017% 16 0.142%~2.062% 0.996%0~0.041%0.023%  Simulation condition:  Speed:100MHz  Light: 5000~10000Lux

20. Processing Speed  Simulation condition:  Light: 10000~11000Lux

21. Scale of the pixel array  Simulation condition:  Light: 3000~4000Lux  Speed: 100MHz

22. Simulation in Specture

23. Signals in CD unit

24. Simulation results for the array