Patent ID: 11885879
Assignee: MITUTOYO CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. A measurement apparatus comprising:
a laser apparatus that has an optical cavity and outputs a frequency-modulated laser beam with a plurality of modes;
a branch that branches a first portion of the frequency-modulated laser beam output by the laser apparatus as a reference light and at least some of a remaining second portion of the frequency-modulated laser beam as a measurement light;
a beat signal generator that generates a beat signal by mixing the reference light and a reflected light that is reflected by radiating the measurement light onto an object;
first analyzer circuitry configured to analyze a first signal component corresponding to a difference in a propagation distance between the reference light and the measurement light on the basis of the beat signal;
second analyzer circuitry configured to analyze a second signal component corresponding to a cavity frequency of the optical cavity on the basis of the beat signal; and
calculation circuitry configured to calculate the difference in the propagation distance between the reference light and the measurement light based on analysis results of the first signal component and the second signal component.