Patent ID: 6803858
Filing Date: 2004-10-12
Classification: B60Q

Abstract:
A vehicle alert system that is mounted in a vehicle comprising:a first photoresistor connected to a first power supply voltage; a second photoresistor connected to the first photoresistor and connected to a second power supply voltage; an operational amplifier having a first input, a second input and an output, wherein the first input is connected to a node that connects the first photoresistor to the second photoresistor, the second input is connected to a resistor, and the output is coupled to an alarm circuit element: and a fresnel lens mounted adjacent to the first photoresistor and the second photoresistor; wherein the resistor has a value of resistance such that selective changes in ambient light detected by the first photoresistor and the second photoresistor cause the operational amplifier to activate the alarm circuit element to generate an alarm.