A novel design for the precise measurement of surface variation based on volume holography is proposed. The volume hologram is a spatial filter, which records the index grating corresponding to the interference fringes by a plane wave and a divergent spherical wave. In the measuring process, a point source attached to a probe is used to read the hologram. A precise measurement can be achieved because the horizontal displacement of the point source is very sensitive to the hologram. This sensitivity is higher than that of a holographic confocal microscopy based on the longitudinal displacement.
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering
- Atomic and Molecular Physics, and Optics