Patent ID: 7054125

Claim:
An X-ray protector for use with a CRT of a TV receiver, said X-ray protector comprising: a power supply circuit operable to supply electrical power to the CRT; a high-voltage detector operable to detect a voltage to be applied to the CRT; an input line; a controller, having an input port to which the input line inputs a detection signal based on the voltage detected by the high-voltage detector, operable to turn off the power supply circuit based on the detection signal; a resistor connected to said input line in series; and a short-circuit device operable, during testing of the X-ray protector, to short-circuit both ends of said resistor so as to raise the voltage of the detection signal; wherein said controller is operable to: turn off said power supply circuit when a voltage greater than or equal to a predetermined voltage is applied to the CRT, the predetermined voltage corresponding to a voltage that would cause the CRT to produce a permissible dose of X-rays; and test the X-ray protector by receiving, through the input port of the controller, the raised-voltage detection signal produced by said short-circuit device, without applying an excessive voltage, which is higher than a normally-applied voltage, to the CRT.