In the competitive industry of optical data storage, larger disk capacities are constantly being sought. One way to increase the data density in an optical disk is to decrease the spot size of the reading and writing beam. Decreasing the spot size by conventional means is diffraction limited by the numerical aperture of available lens technologies and the wavelength of light used. Superresolution, or manipulation of the input beam profile, can be used to further decrease the size of the spot on the disk surface to below its classical diffraction limit. The current method of superresolution in optical memory m suffers from a low signal-to-noise ratio and only decreases the spot diameter by 80%. This method uses a shading band to perform spatial filtering on the fundamental Gaussian beam created by a collimated laser diode. An alternative method is suggested in this paper, which generates a superresolved spot by introducing a mask function into the Fourier plane of a Vertical Cavity Surface Emitting Laser (VCSEL) that exhibits a high-order Laguerre-Gaussian output mode. Theoretical results show a decrease in spot size by up to 47% in two dimensions.
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