In intersatellite optical communications(IOC),a pointing-acquisition-tracking(PAT) subsystem with high angular error detection frequency is a matter of a great importance for the assurance of the stability of laser link and the quality of communication.To satisfy the need of high speed PAT angular error detection devices,a new detection device based on binary optics element(BOE) and an improved facular centroid algorithm adopted in this device are presented.After incident optical beam is focused and shapod by a BOE,two dimensional angular detection can be accomplished by an one dimensional linear scan CCD.The simulation results have shown an angular detection frequency of tens of kHz,an angular detection error of 2.84% and a BOE efficiency of 83.9%.Compared with the traditional angular detection device based on surface scan CCD,the algorithm complexity is decreased from O(N~2) to O(N) and the hardware complexity can also be highly simplified in this new device.