Abstract: An isolated voltage probe includes: a conductor including a positive lead, a negative lead, and a resistance via which the positive lead and the negative lead are connected to each other; a magnetic sensor for measuring a magnetic field in a non-contact manner, the magnetic field being generated by a current flowing through the conductor; and a coaxial cable for transmitting a signal that is based on an output supplied from the magnetic sensor.

Abstract: An electronic device includes a display unit, and an operation unit. The electronic device has a lock function of locking operation functions on the operation unit such that the operation functions are temporarily inoperable. At least one of the operation functions is set to be selectively operable even in a lock state.

Abstract: An optical pulse tester includes: an OTDR measurer configured to execute an OTDR function of measuring a time distribution of a power of return light of an optical pulse input to an optical fiber; a display configured to display an OTDR measurement screen indicating information on execution of the OTDR function; and a controller configured to control the OTDR measurer and the display. The controller displays, on the OTDR measurement screen, a menu for allowing an operating person to call an auxiliary function for measurement of the optical fiber, and displays, on the OTDR measurement screen, a sub-screen indicating information on execution of the auxiliary function called by the operating person.

Abstract: An optical device includes: a diffraction grating; a depolarization plate containing a birefringent material to eliminate polarization dependency of the diffraction grating; and an optical corrector configured to optically correct diffraction angle deviation of diffracted light due to diffraction at the diffraction grating. The optical corrector may be configured to bend back the diffracted light diffracted by the diffraction grating to re-emit the light to the diffraction grating.

Abstract: An optical pulse tester includes: an OTDR measurer configured to execute an OTDR function of measuring a time distribution of a power of return light of an optical pulse input to an optical fiber; a display configured to display an OTDR measurement screen indicating information on execution of the OTDR function; and a controller configured to control the OTDR measurer and the display. The controller displays, on the OTDR measurement screen, a menu for allowing an operating person to call an auxiliary function for measurement of the optical fiber, and displays, on the OTDR measurement screen, a sub-screen indicating information on execution of the auxiliary function called by the operating person.

Abstract: An optical wavelength meter includes: an interferometer; a reference optical source unit with a laser configured to oscillate in a multi-longitudinal mode; and a signal processor configured to calculate a wavelength of a input beam with reference to interference fringe information of reference beam and interference fringe information of the input beam obtained from the interferometer.

Abstract: A charging circuit for charging a rechargeable battery, the charging circuit includes: a switching element connected to a power supply; a pulse width controller configured to control open and close of the switching element; and a MOSFET arranged between the switching element and the rechargeable battery. The charging circuit may further include a thermistor connected between a gate and a source of the MOSFET.

Abstract: An optical measuring apparatus includes a measuring device configured to measure, by a shot unit, data in a predetermined wavelength range, a controller configured to analyze the measured data, a storage storing the measured data of a plurality of shots and the analysis results of the measured data, and a display configured to display the analysis results and waveform data based on the measured data on a single display screen.

Abstract: An optical wavelength meter includes: an interferometer; a reference optical source unit with a laser configured to oscillate in a multi-longitudinal mode; and a signal processor configured to calculate a wavelength of a input beam with reference to interference fringe information of reference beam and interference fringe information of the input beam obtained from the interferometer.