Real-time holography

Abstract

As part of our coherent optics course for senior level undergraduates, our students complete a laboratory in which they are trained in laser safety and set up a complete holographic system. The students perform all phases of the setup from aligning pinholes for spatial filters to ensuring the correct illumination levels for plate exposure. The students are then required to investigate some aspect of holography. The topic may be of their own choosing or can be selected from a list of topics provided by the instructor. In this paper we will describe the contribution of various student groups to the analysis of vibrating objects with or without static deformation using real-time holography. Three years ago we started this project by asking two very simple questions; first, 'why are there twice as many fringes in time-average holography?'; and second, 'can the fringe contrast for real-time holography be enhanced?' In the course of this research, we 'discovered' quite a few things which were already well known, and a few things that are not. But in the course of this work, all of the authors, faculty and students, enhanced our understanding of holography and its applications.