Patent ID: 7424177

Claim:
A voltage measurement system sensing and displaying an electrical signal from a device under test comprising: a measurement instrument processing and displaying the electrical signal from the device under test; a variable attenuation signal acquisition probing system coupled to the measurement instrument and sensing the electrical signal from the device under test using electro-optic detection comprising: an optical transmitter generating a variable polarized, tunable, coherent optical signal; an optical receiver generating an output electrical signal coupled to the measurement instrument; circuitry for controlling the optical power level and wavelength of the tunable, coherent optical signal from the optical transmitter and the gain of the output electrical signal from the optical receiver; an optical cavity having optically reflective material disposed on opposing surfaces of an electro-optic material with the tunable, coherent optical signal propagating through at least one of the optically reflective materials and within the electro-optic material; first and second electrically conductive electrodes receiving the electrical signal from the device under test with each of the first and second electrically conductive electrodes having an apertures formed in at least a portion of the electro-optic material generally parallel to the received optical signal propagating within the electro-optic material and electrically conductive material disposed within each of the first and second apertures; an optical transmission system optically coupled to the optical transmitter, optical receiver and one of the optically reflective materials of the optical cavity providing the optical signal from the optical transmitter to the optical cavity and providing a modulated optical signal to the optical receiver representing the electrical signal from the device under test derived from the device under test electrical signal creating an electro-magnetic field distribution in the electro-optic material that overlaps the optical path of the optical signal propagating in the electro-optic material and varies the index of refraction of the electro-optic material in the optical path; and a variable polarizer receiving the tunable, coherent optical signal and varying the polarization state of tunable, coherent optical signal to vary the magnitude of the output electrical signal of the optical receiver.