Chameleon Laser A hands-free, single-box, ultrafast Ti:sapphire laser from Coherent Inc. in Santa Clara, Calif., the Chameleon provides femtosecond-pulse tuning from 720 to greater than 930 nm. Developed primarily for multiphoton excitation microscopy, this flexible laser oscillator also can be used for a wide range of ultrafast research applications, including time-resolved photoluminescence, nonlinear spectroscopy, fluorescence upconversion and quantum chemistry. It can excite fluorescent media such as green and yellow fluorescent proteins.Besides tuning over a range of more than 210 nm, the fully automated Chameleon provides more than 1 W of average power and features a sealed, maintenance-free design with a menu-driven interface. The laser also incorporates features such as the Power Pulse system for long-term stability. With this system, active pointing control works with a patent-pending dispersion-balanced tuning mechanism to ensure that output power and pulse width are automatically optimized across the full tuning range.The laser also has a patent-pending miniature air recirculator that allows tuning through atmospheric water vapor absorption lines above about 920 nm without the need for an external purge.