| 摘要 |
An apparatus for medical diagnosis and/or therapy includes an electromagnetic obstacle sensor in order to prevent collisions with, for example a patient to be examined. The sensor is constructed so as to include a radiation transmitter and a radiation receiver in the form of capacitive electrodes 16 and 18, respectively, whereto electronic circuits 26 and 28 for signal processing are connected. In order to enable the electrodes 16 and 18 and the electronic circuits 26 and 28 to be checked for correct operation, a test electrode 14 is connected between the transmitter electrode 16 and the detection electrode 18, which test electrode can be connected, if desired, to a point 32 of fixed voltage via a controllable switch 34. The presence of an obstacle is thus simulated. The output signal of the electronic circuits 26 and 28 can be checked to determine whether this output signal corresponds to the situation in which an obstacle is present. |
