Optical voltage probe

An optical voltage probe comprising:

• an optical modulator having at least two modulation electrodes, the optical modulator being configured to modulate an intensity of an incident light depending on a voltage between the two modulation electrodes and output the incident light which is modulated;
• an input optical fiber that is connected with the optical modulator;
• an output optical fiber that is connected with the optical modulator;
• two contact terminal attachment portions to which two contact terminals can be detachably attached and contacted, the two contact terminals being connected with the two modulation electrodes and configured to be in contact with the points to be measured;
• and
• a package that houses the optical modulator, a part of the input optical fiber and a part of the output optical fiber, wherein
• the two contact terminal attachment portions are installed inner than a position of a surface of the package,
• a voltage signal induced between the two modulation electrodes via the two contact terminal is converted into an optical intensity modulation signal by the optical modulator and the optical intensity modulation signal is outputted through the output optical fiber so that the voltage signal induced between the two modulation electrodes is measured based on the optical intensity modulation signal, and
• when an electric wave having a measurement frequency is applied while the two contact terminal attachment portions are opened, the package exhibits a shielding effect of attenuating the electric wave by 15 dB or more compared to an output signal intensity measured without providing the package.

An optical voltage probe comprising:

• an optical modulator having at least two modulation electrodes, the optical modulator being configured to modulate an intensity of an incident light depending on a voltage between the two modulation electrodes and output the incident light which is modulated;
• an input optical fiber that is connected with the optical modulator;
• an output optical fiber that is connected with the optical modulator;
• two contact terminals or two contact terminal attachment portions to which the two contact terminals can be detachably attached and contacted, the two contact terminals being connected with the two modulation electrodes and configured to be in contact with points to be measured;
• a package that houses the optical modulator, a part of the input optical fiber and a part of the output optical fiber, wherein
• a voltage signal induced between the two modulation electrodes via the two contact terminals is converted into an optical intensity modulation signal by the optical modulator and the optical intensity modulation signal is outputted through the output optical fiber so that the voltage signal induced between the two modulation electrodes is measured based on the optical intensity modulation signal,
• the package includes an electric wave absorber for reducing a reflection of an electromagnetic wave arrived from an outside of the package and reflected by the package, and
• when an electric wave having a measurement frequency is applied while the two contact terminals or the two contact terminal attachment portions are opened, the package exhibits a shielding effect of attenuating the electric wave by 15 dB or more compared to an output signal intensity measured without providing the package.