*** 9760821 Vujkovic-Cvijin This Small Business Innovation Research (SBIR) Phase I project will develop a mid-infrared (2-5.5 micron) diode-based laser source for atmospheric spectroscopy and remote sensing, which operates without cryogenic cooling. The instrument is based on the frequency conversion of near infrared radiation of III-V diode lasers further in the infrared. A novel approach to increase the output power is described. In Phase I the instrument will be tested with increased frequency conversion. During Phase II an optimized source would be built, and a working prototype prepared for production. The miniature, narrowband laser source operating at room temperature in the mid-infrared region will be used a primarily as the radiation source for optical trace gas sensors. Sensors based on this source will be commercially applicable in medical diagnostics, industrial process control, and environmental monitoring. ***