Multiwavelength laser for illumination of photo-dynamic therapy drugs

An apparatus and method are provided for converting a pump laser beam having a first wavelength to an output beam of a second wavelength. The wavelength conversion device includes a solid medium impregnated with dye laser which is rotated at a speed which is slow enough to allow the dye material to lase and fast enough to reduce thermally induced optical aberrations and triplet state absorption. The medium and method provide a variety of output laser wavelengths suitable for treating diseases of the eye. In the preferred embodiment, the medium has the dimensions of a standard compact disk.