Optical sensor

An optical sensor comprising an optical unit and a signal processing unit, wherein

• said optical unit has on an optical axis;
• a first polarizer which is arranged at a light input side,
• a second polarizer which is arranged at a light output side, the polarization direction of which is substantially parallel or perpendicular to that of said first polarizer,
• a first light wave phase modulator which are arranged between the first and second polarizers, for phase-modulating light wave according to a value which is obtained by time-integrating a physical dimension to be measured,
• a second light wave phase modulator which are arranged between the first and second polarizers, for phase-modulating light wave according to a control modulation physical dimension which has higher frequency of that of the physical dimension to be measured, and
• said first and second light wave phase modulators being arranged in a manner that directions of light wave phase modulation in said modulators are parallel or perpendicular to each other, and
• said signal processing unit has;
• an O/E converter which converts intensity of light of said optical unit into an electric signal,
• a phase shifter which shifts a phase of said control modulation physical dimension applied to said second light wave phase modulator by .pi..times.n.+-..pi./2 radians (n:
• an integer),
• an adder which adds an output of said O/E converter to an output of said phase shifter, and
• a demodulator which demodulates an output of said adder.

An optical sensor comprising an optical unit and a signal processing unit, wherein

• said optical unit has on an optical axis;
• a first polarizer which is arranged at a light input side,
• a second polarizer which is arranged at a light output side, the polarization direction of which is substantially parallel or perpendicular to that of said first polarizer,
• a first light wave phase modulator which are arranged between the first and second polarizers, for phase-modulating light wave according to physical dimension to be measured,
• a second light wave phase modulator which are arranged between the first and second polarizers, for phase-modulating light wave according to a control modulation physical dimension which has higher frequency of that of the physical dimension to be measured, and
• said first and second light wave phase modulators being arranged in a manner that directions of light wave phase modulation in said modulators are parallel or perpendicular to each other, and
• said signal processing unit has;
• an O/E converter which converts intensity of light of said optical unit into an electric signal,
• a phase shifter which shifts a phase of said control modulation physical dimension applied to said second light wave phase modulator by .pi..times.n+.pi./2 radians (n:
• an integer),
• an adder which adds an output of said O/E converter to an output of said phase shifter, and
• a demodulator which demodulates an output of said adder, and
• wherein
• said sensor further comprises:
• an oscillator which is powered by a current flowing through an electric wire to be measured and oscillates a signal for obtaining said control modulation physical dimension;
• and
• a potential divider which divides a voltage between a ground and said electric wire to be measured for obtaining said physical dimension to be measured, and
• said sensor further comprises:
• an auxiliary unit which gets a current to be measured of an electric wire to be measured for obtaining said physical dimension to be measured,
• and further
• said physical dimension to be measured is a voltage and a current of an electric wire to be measured, thereby to simultaneously measure said voltage and said current.