Patent ID: 8431898
Filing Date: 2013-04-30
Classification: G02B

Abstract:
1. An infrared cut filter removable (ICR) module control apparatus comprising: a power supply; a first resistor; a photoresistor comprising a first terminal connected to the power supply through the first resistor, and a grounded second terminal; a central processing unit (CPU); first to sixth electronic switches, wherein a node between the first resistor and the photoresistor is connected to the second to fourth electronic switches and the CPU through the first electronic switch, the second electronic switch is connected to the fifth and sixth electronic switches; an ICR module comprising a first input terminal and a second input terminal, wherein the ICR module is switched between a normal light filter mode and an infrared filter mode by changing a voltage difference between the first and second input terminals, a node between the third and fourth electronic switches is connected to the first input terminal, a node between the fifth and sixth electronic switches is connected to the second input terminal; and a comparator comprising a non-inverting terminal connected to the first input terminal of the ICR module, an inverting terminal connected to the second input terminal of the ICR module, and an output terminal; wherein the CPU is connected to the output terminal of the comparator and the first electronic switch, the first electronic switch is switched by the change of the resistance of the photoresistor, then controls the states of the second to sixth electronic switches to switch the voltage difference between the first and second input terminals of the ICR module, the CPU compares a first signal from the first electronic switch and a second signal from the comparator to determine whether the ICR module is switched to a correct mode; and wherein the first and second electronic switches are npn transistors, the third and fifth electronic switches are p-channel metal-oxide semiconductor transistors, the fourth and sixth electronic switches are n-channel metal-oxide semiconductor transistors, the node between the first resistor and the photoresistor is connected to the base of the first electronic switch through a second resistor, the emitter of the first electronic switch is grounded, the collector of the first electronic switch is connected to the power supply through a third resistor, connected to the base of the second electronic switch through a fourth resistor, connected to the gates of the third and fourth electronic switches, and connected to the CPU; the emitter of the second electronic switch is grounded, the collector of the second electronic switch is connected to the power supply through a sixth resistor and connected to the gates of the fifth and sixth electronic switches, the drains of the third and fifth electronic switches are connected to the power supply, the sources of the third and fifth electronic switches are respectively connected to the drains of the fourth and sixth electronic switches, the sources of the fourth and sixth electronic switches are grounded.