Patent ID: 9423238
Filing Date: 2016-08-23
CPC Classification: A61B,G01B

Claim Text:
1. An optical measurement apparatus comprising: a light source configured to emit a laser beam; at least one first optical splitter configured to split the laser beam into a reference beam and an other beam; at least one second optical splitter configured to split the other beam into a signal beam and a control beam; an objective lens configured to focus the signal beam onto a target to be measured and irradiate the target to be measured with the signal beam; a first actuator configured to move a focus position of the signal beam; a second actuator configured to control an amount of defocus of the control beam; a optical phase modulator configured to control a phase difference between the control beam and the signal beam, wherein the at least one second optical splitter is further configured to combine a signal beam reflected or scattered by the target to be measured with the control beam to generate a controlled signal beam; interference optics configured to combine the controlled signal beam with the reference beam to generate a plurality of interference beams with different phases; a photodetector configured to detect the interference beams; a controller configured to control the first actuator, the second actuator, and the optical phase modulator.