Abstract: There is provided a conversion system for use with commercially available laser devices for medical applications where laser light at a predetermined wavelength is converted for simultaneous coaxial application of laser light at a plurality of predetermined medically useable wavelengths. The conversion system includes focusing structure for focusing laser radiation at predetermined pump wavelength into a conversion medium. The conversion medium is prepared for efficient conversion of a portion of the radiation at the input pump wavelength to a signal wavelength, wherein, in one preferred application, either the pump or signal wavelength is in a range of between about 2.7 and about 3.25 microns. The system further includes structure for coaxially transmitting laser radiation at the resulting plurality of wavelengths from the conversion system for simultaneous use.