Innovative measurement of parallelism for parallel transparent plate based on optical scanning holography by using a...

A potential method is proposed to measure the parallelism of parallel transparent plate with an advanced lower limit and a convenient process by optical scanning holography (OSH) using a random-phase pupil, which is largely distinct from traditional methods. As a new possible application of OSH, this promising method is demonstrated theoretically and numerical simulations are carried out on a 2  cm×2  cm parallel plate. Discussions are also made on the quality of reconstructed image as well as local mean square error (MSE), which are closely related with the parallelism of sample. These amounts may become the judgments of parallelism, while in most interference methods judgments are paces between two interference fringes. In addition, randomness of random-phase pupil also affects the quality of reconstructed image and local MSE. According to the simulation results, high parallelism usually brings about distinguishable reconstructed information and suppressed local MSE.