METHOD AND APPARATUS FOR SELECTIVE BLANKING OF A LICENSE PLATE USING MULTIPLE LIGHT SENSORS

摘要

A blanking device generates a blanking signal to obscure signals on a license plate in response to a monitoring flash directed at the license plate. The device includes at least two sensors spaced apart to enable the device to differentiate between a monitoring flash from a device attempting to take an image of the license plate and other spurious signals.

主权项

1. A blanking device for selectively blanking symbols on a license plate of a motor vehicle in response to a monitoring flash from a device configured to take an image of the license plate, the blanking device comprising:
a first and a second light sensor arranged to detect incident light, said light sensors being spaced away from each other by a predetermined distance, said first and second sensors generating respective first and second signals; a signal analyzer receiving said first and second signals and being configured to differentiate said monitoring flash from other spurious light by detecting a delay between said first and second signals, and generating an output indicative of said monitoring flash; and a blanking flash generator coupled to said signal analyzer and generating a blanking flash at the license plate in response to said monitoring flash, said blanking flash obscuring symbols on the license plate to the device.