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An adaptive simulated annealing optimization algorithm is used to derive laser rate equation and waveguiding models with which the best design for a diode-pumped fiber-coupled, Yb:Er glass waveguide laser can be determined. Material parameters that correspond to commercially available laser-glass and diode-pump sources are used in this study. Given a continuous-wave 300-mW pump at 977 nm, approximately 48 mW of power at 1540 nm can be coupled into the LP(01) mode of an optical fiber. Fabrication and alignment tolerance analyses are presented.

We investigated an Er(3+)/Yb(3+) codoped silicate glass as a host material for waveguide lasers operating near 1.5 microm. Spectroscopic properties of the glass are reported. Waveguide lasers were fabricated by K(+)-ion exchange from a nitrate melt. The waveguides support a single transverse mode at 1.5 microm. An investigation of the laser performance as a function of the Yb:Er ratio was performed, indicating an optimal ratio of approximately 5:1. Slope efficiencies of as great as 6.5% and output powers as high as 19.6 mW at 1.54 microm were realized. The experimental results are compared with a waveguide laser model that is used to extract the Er(3+) upconversion coefficients and the Yb(3+)-Er(3+) cross-relaxation coefficients. The results indicate the possibility of obtaining high-performance waveguide lasers from a durable silicate host glass.

A study of gradient-index eyepieces was conducted. The general performance of homogeneous eyepieces having two and three elements was examined. Axial gradients were introduced into the eyepieces in an attempt to increase the half-fields of view to 25 degrees and extend the eye reliefs to 12 mm. The homogeneous eyepieces examined were of the Huygenian, Ramsden, and Kellner configurations. These eyepieces were scaled to the specifications of f/13, 21.4-mm focal length, and magnifying power of 10X. These classic systems were optimized to produce two- and three-element homogeneous eyepieces to determine how homogeneous systems could perform with the extended eye relief and larger field of view. Axial gradient eyepieces having two and three elements were designed to the same specifications. The balance of third-order aberrations, color, and distortion was maintained or improved compared to the homogeneous systems.. The additional degrees of freedom associated with the gradient made it possible to extend the eye relief and increase the field of view of these eyepieces.

A new instrument for measuring the evolution of index profiles during diffusion in hot (500 degrees C) glass is presented. This instrument, called the oven interferometer, has a spatial resolution of 10 microm at 0.6471 microm and a phase resolution of lambda/50. The development of index profiles with both time-dependent and constant boundary conditions is shown.

A two-element gradient-index photographic objective was designed. It operates at f/2 and has a focal length of 50 mm. The half-field of view is 21.8 degrees . The design is compared to the six-element new double Gauss photographic objective and performs well in comparison.