Elaboration of a method to determine the surface shape of small elements using partial coherence illumination and digital holography

Aim of project
The scientific aim of the project was the elaboration of a method of measuring surface shape of microelements. For microelements of millimeter dimensions, the problem was solved using registration of the interferometric fringe pattern generated on the studied surface by the propagation of two planewaves. In case of microelement dimensions not greater than 0.5 mm, a determination of optical fi eld transmitted by this element has been proposed. Microlens has been chosen as microelements. For that purpose, a Mach-Zehnder interferometer was used. Two measurement methods are considered: (1) registration of fringe patterns for various positions of the microlens along the optical axis; (2) registration of one fringe pattern (treated as a hologram) for a chosen position of the microlens and the determination of the optical fi eld using a software program basing on diff raction. The registration of one fringe pattern allows only dynamic measurements. The proposed solution is innovative. The project combines theoretical considerations and measurements on a laboratory stand.

Expected results
The final result of the project will be the elaboration of a new method of measuring microelement shapes, a Ph.D. dissertation and an article published in Opto -Electronics Review.