Abstract: A sound pressure metrology instrument determines sound pressure from index of refraction and includes: a light source that produces source light; the optical cavity that: receives an acoustic field from the sound source; receives the source light from the light source; produces acoustic-modified light from the source light; and communicates the acoustic-modified light to the photodetector; the photodetector that receives the acoustic-modified light from the optical cavity, produces an acoustic-modified signal from the acoustic-modified light, and communicates the acoustic-modified signal to the analyzer module; the analyzer module in electrical communication with the photodetector and that receives the acoustic-modified signal from the photodetector and determines the sound pressure of the acoustic field produced by the sound source from the modulations in the index of refraction of the acoustic medium inside the optical cavity encoded in the acoustic-modified light.

Abstract: A calibration apparatus for calibrating a laser Doppler vibrometer includes: a frequency shifter stage that: receives, from the laser Doppler vibrometer, primary laser light; produces frequency shifted light; communicates the frequency shifted light to a reflector; receives frequency shifted light reflected by the reflector; produces secondary light; and communicates the secondary light to the laser Doppler vibrometer, such that the laser Doppler vibrometer receives the secondary light from the frequency shifter stage and produces a synthetic velocity shift from the secondary light; and the reflector that receives and reflects the frequency shifted light back to the frequency shifter stage.

Abstract: A calibration apparatus for calibrating a laser Doppler vibrometer includes: a frequency shifter stage that: receives, from the laser Doppler vibrometer, primary laser light; produces frequency shifted light; communicates the frequency shifted light to a reflector; receives frequency shifted light reflected by the reflector; produces secondary light; and communicates the secondary light to the laser Doppler vibrometer, such that the laser Doppler vibrometer receives the secondary light from the frequency shifter stage and produces a synthetic velocity shift from the secondary light; and the reflector that receives and reflects the frequency shifted light back to the frequency shifter stage.