A novel, to our knowledge, method for the measurement of angular displacement for arbitrarily shaped objects is presented in which the angular displacement is perpendicular to the optical axis. The method is based on Fourier-transforming the scattered field from a single laser beam that illuminates the target. The angular distribution of the light field at the target is linearly mapped on a linear image sensor placed in the Fourier plane. Measuring this displacement facilitates the determination of the angular displacement of the target. It is demonstrated both theoretically and experimentally that the angular-displacement sensor is insensitive to object shape and target distance if the linear image sensor is placed in the Fourier plane. A straightforward procedure for positioning the image sensor in the Fourier plane is presented. Any transverse or longitudinal movement of the target will give rise to partial speckle decorrelation, but it will not affect the angular measurement. Furthermore, any change in the illuminating wavelength will not affect the angular measurements. Theoretically and experimentally it is shown that the method has a resolution of 0.3 mdeg ( approximately 5 murad) for small angular displacements, and methods for further improvement in resolution is discussed. No special surface treatment is required for surfaces giving rise to fully developed speckle. The effect of partially developed speckle is considered both theoretically and experimentally.

We have fabricated a novel optically addressed spatial light modulator by using bacteriorhodopsin immobilized in a polymer thin film. This incoherent-to-coherent converter is based on photoinduced anisotropy, as distinguished from previously reported devices based on photochroism in bacteriorhodopsin. This system is capable of a resolution of 114 lines/mm with a contrast ratio of 100:1.

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Reducing the complexity of opticalsystems emphasizes the need to increase the number of optical functions in as few modules as possible, making the system more compact and simple to operate. Optical functions such as light generation, frequency conversion, amplification, broadband transmission, wavelength filtering and interfacing to the outside environment typically needed separate, individual optical components to be chained together to comprise a system. However, with the advent of Photonic Crystal Fiber, many of these functions can be combined into multifunctional modules paving the way for simpler, turn‐key systems.

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