Parallel Flat Crystal
Parallel flat crystal is used to verify the flatness of the measuring surface of micrometers, lever calipers and micrometer calipers and the parallelism of two relative measurements.
Parallel flat crystal is based on the principle of light wave interference, and uses the interference fringes that appear between the plane of the flat crystal and the measured surface of the test piece to measure the degree of error of the measured surface. Generally composed of 4 flat crystals with different thicknesses, or one can be used alone. Parallel flat crystals have high-precision planarity and parallelism.
