The hydrogenated amorphous silicon active hollow four quadrant orientation detector for application to neural network image sensors

The fundamental way to improve the processing speed of pattern recognition is to implement the data processing function by hardware circuits. A simple integrated device by combining hollow four quadrant orientation detector (hollow FOQUOD) with an amorphous silicon thin film transistor as a switch element has been successfully fabricated. This device is called active hollow FOQUOD. The hollow FOQUOD detector can extract the edge position and its orientation from an object image with a precision of 5° which is consistent with the theoretical simulation. It is demonstrated that the thin film transistor can indeed switch the hollow FOQUOD detector on and off and avoid the crosstalk problem when used in a 3×3 two-dimensional array