Single sensor ring laser gyroscope

A method for fabricating a ring laser gyroscope which incorporates a single optical sensor, said method comprising:

• configuring the optical sensor to receive an optical fringe pattern and output two signals about ninety degrees out of phase from one another, where the signals are representative of an angle and the frequency of the signals is representative of a rate of turn sensed by the ring laser gyroscope;
• providing an amplification circuit to amplify the two signals;
• providing a squaring function configured to square each of the amplified signals;
• providing a bandpass filter configured to receive one of the squared signals, an output of the bandpass filter representative of a residual path length control modulation signal;
• and
• providing a summing circuit configured to add together the squared signals, an output of the summing circuit representative of a laser intensity monitor signal.

A method for fabricating a ring laser gyroscope which incorporates a single optical sensor, said method comprising:

• configuring the optical sensor to receive an optical fringe pattern and output two signals about ninety degrees out of phase from one another, where the signals are representative of an angle and the frequency of the signals is representative of a rate of turn sensed by the ring laser gyroscope;
• providing an amplification circuit to amplify the two signals;
• providing a bandpass filter configured to receive one of the amplified signals, an output of the bandpass filter representative of a residual path length control modulation signal;
• and
• providing a low pass filter configured to filter one of the amplified signals, an output of the low pass filter representative of a laser intensity monitor signal.

A ring laser gyroscope comprising:

• an optical sensor configured to receive a portion of the energy from a pair of counter-propagating laser beams in a fringe pattern, said optical sensor comprising dual photo diodes configured to output signals that are out of phase from one another by about one-half period;
• an amplification circuit configured to amplify and output the signals, where the signals are representative of an orientation and the frequency of the signals is representative of a rate of turn sensed by said ring laser gyroscope;
• a squaring circuit configured to square the outputs of said amplification circuit;
• a bandpass filter configured to receive one of the outputs of said squaring circuit, an output of said bandpass filter configured to be representative of a residual path length control modulation signal;
• and
• a summing circuit configured to add together outputs of said squaring circuit, an output of said summing circuit configured to be representative of a laser intensity monitor signal.

A ring laser gyroscope comprising:

• an optical sensor configured to receive a portion of the energy from a pair of counter-propagating laser beams in a fringe pattern, said optical sensor comprising dual photo diodes configured to output signals that are out of phase from one another by about one-half period;
• an amplification circuit configured to amplify and output the signals, where the signals are representative of an orientation and the frequency of the signals is representative of a rate of turn sensed by said ring laser gyroscope;
• a bandpass filter configured to receive one of the amplified signals, an output of said bandpass filter representative of a residual path length control modulation signal;
• and
• a low pass filter configured to receive one of the amplified signals, an output of said low pass filter configured to be representative of a laser intensity monitor signal.