Introduction F. J. Duarte Spectroscopic Applications of Tunable Optical Parametric Oscillators B. J. Orr, R. T. White, and Y. He Solid-State Dye Lasers Costela, I. Garcia-Moreno, and R. Sastre Tunable Lasers Based on Dye-Doped Polymer Gain Media Incorporating Homogeneous Distributions of Functional Nanoparticles F. J. Duarte and R. O. James Broadly Tunable External-Cavity Semiconductor Lasers F. J. Duarte Tunable Fiber Lasers T. M. Shay and F. J. Duarte Fiber Laser Overview and Medical Applications S. Popov Medical Applications of Dye Lasers Costela, I. Garcia-Moreno, and R. Sastre Biological Microscopy with Ultrashort Pulses J. L. Thomas and W. Rudolph Tunable, Monochromatic X-Rays: Medical and Non-Medical Applications F. E. Carroll Lithium Spectroscopy Using Tunable Diode Lasers E. Olivares Interferometric Imaging F. J. Duarte Multiple-Prism Arrays and Multiple-Prism Beam Expanders: Laser Optics and Scientific Applications F. J. Duarte Coherent Electrically-Excited Organic Semiconductors F. J. Duarte Appendix on Optical Quantities and Conversions of Units F. J. Duarte