An apparatus and system includes a radiation generation device for generating radiation and a radiation detection device. A first radiation channel is optically-coupled on a first end to the radiation generation device and configured to direct the radiation generated by the radiation generation device to a second end of the first radiation channel. A second radiation channel is optically-coupled on a first end to the radiation detection device and configured to direct radiation from a second end of the second radiation channel to the radiation detection device. An optical switch is configured to selectively interrupt the transmission of radiation from the second end of the first radiation channel to the second end of the second radiation channel.