5 W yellow-orange compact semiconductor laser for the treatment of vascular lesions

ObjectiveThe availability of compact and reliable yellow-orange (575-595 nm) lasers is essential in the treatment of cutaneous vascular lesions, such as port wine stains. Optically pumped semiconductor lasers have emerged as an attractive alternative to solid-state and dye lasers due to their compactness, cost, reliability and wavelength coverage. They are able to produce high power yellow-orange light via frequency doubling in continuous wave as well as in microsecond pulses. The main objective of this study is to develop a 5 W yellow-orange optically pumped semiconductor laser and experimentally evaluate its efficiency in the treatment of cutaneous vascular lesions. Study Design & MethodsThe optically pumped semiconductor laser, also known as VECSEL (vertical external-cavity surface-emitting laser) consists of a semiconductor gain mirror and typically two highly reflective external mirrors, which form the V-shaped external cavity. The laser is designed to emit light around 1180 nm, which is converted to the yellow-orange spectral range via intra-cavity frequency doubling using a nonlinear crystal. The yellow-orange output is coupled to a fiber from which it can be delivered to a targeted area. ResultsWe have developed a yellow-orange laser producing 5 W of laser light around 590 nm for the treatment of vascular lesions. Millisecond pulses can be generated by utilizing a handheld scanning device. ConclusionVECSELs offer a reliable and compact light source for the treatment of cutaneous vascular lesions. Other prospective medical applications for VECSELs include microscopy, PDT and ophthalmology.