In this paper, we present a suite of novel speckle based displacement sensors. A laser beam illuminates the optically rough object and the light scattered off the object is collected and processed by various optical elements and, finally, the speckle pattern is detected. A new theoretical tool has been developed in which the speckle dynamics at the detector plane is described for an arbitrary complex optical system simply by means of the ABCD ray-transfer matrix elements for the optical system. Armed with the general theoretical tool, this paper discusses the correlation between object displacement and the speckle dynamics observed at the detector. In particular, the general theoretical tool allows trade-of analyses that are very important for industrial applications. As an example, all the sensors presented here are designed such that they are independent on variations in object distance. A new method is introduced in which rapid prototype optical sensors can be realized with standard optical elements. This facilitates a way of rapid realization of very compact optical sensors.
Optimal construction of stereograms requires accordance between recording conditions of the 2 dimensional recording and the subsequent holographic master recording.
In recording of different stereograms for use in mass productions it is appropriate to be capable of changing the recording conditions. This can be achieved by approximating the optimal holographic recording. The approximation is accomplished by use of different recording principles in the 2 dimensional and the holographic recording. As a result image aberrations occur in the stereograms.
For evaluating the magnitude of image aberrations a computer program was developed. The program simulates the image aberrations observed as a result of different viewing angles and distances in respect to the final holographic stereogram.