Low-index embedded waveguide lenses in GaAs substrates

An integrated optical lens structure which embeds a low-index waveguide lens region in a high-index host waveguide is discussed. The lens has been realized on a GaAs/GaAlAs waveguide using an embedded low-index lens structure of glass/SiO/sub 2/. At an f-number of 2 and a wavelength of 1.152 mu m, the focal spot size is 2.8 mu m. The throughput efficiency is 45% and the angular field of view is 10 degrees .<
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