DESCRIPTION (Verbatim from the Applicant's Abstract): Due to the strong water absorption bands in the about 3micro spectral region, 3-micro laser radiation is extremely appropriate for surgical intervention, especially where only shallow cutting beam penetration (incision depth of the order of 20-30 micro) is needed. The aim of the proposal is to develop a novel 3-micro laser scalpel technology for stereotactic surgery using a technical approach that would go around the well-known problem of the 3-micro radiation delivery to internal organs. Out innovative approach is based on replacing the presently technically complicated fiber delivering of the operative3-micro radiation to the undergoing surgery organ by a well developed fiber delivering of the laser diode source radiation in the 0.9-1-micro region of spectrum with its subsequent down-conversion into a 3-micro laser radiation directly in a small surgical instrument tip. We will develop a miniature 30 hz repetition rate, 3mJ/pulse source of the 3-micro laser radiation, which is based on an activated dielectric single crystal pumped through a commercially available low-loss silica glass optical fiber by a commercial InGaAs diode bar stack. Based on mature laser diode pump source/fiber optics technologies, the proposed system in truly easily commercializable and will be then incorporated into a phase II fiber-tip laser scalpel for stereotactic surgery. PROPOSED COMMERCIAL APPLICATION: NOT AVAILABLE