The invention belongs to the technical field of dispersion
confocal displacement measurement, wherein the detection of the inner surface
topography information of a hole sample can be rapidly achievedby using a self-rotating
light beam deflection technology and combining a dispersion
confocal displacement measurement technology. According to the method, a
light beam deflection mechanism is used for deflecting a measurement
light beam emitted by a dispersion objective lens by a certain angle and focusing the measurement light beam on the inner surface of a hole sample, a
confocal spectrum detection
system is used for spatially filtering the light beam reflected by the hole sample and detecting the spectral information of the light beam, the displacement information of the inner surface ofthe hole sample in the
optical axis direction of the measurement light beam is obtained by
processing the detected spectral information, and the
optical axis of the measurement light beam rotates around the
optical axis of the dispersion objective lens to be focused at different positions of the inner surface of the hole sample by rotating the light beam deflection mechanism, so that the displacement information of different positions of the inner surface of the hole sample in the optical axis direction of the measurement light beam is obtained. According to the invention, the light beam deflection technology and the dispersion confocal measurement technology are combined, so that the inner surface
topography information of the hole sample can be directly measured, and a new idea is provided for detection of the inner surface size error, the shape error, the
position error and the defect information of the hole sample.