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An optical system to perform the semiconductor laser myringotomy with the help of a video display and a pilot laser was designed and manufactured.First,the 650 nm laser output from a single emitter and the 810 nm laser emitted from a laser diode array were coupled into a fiber with a core diameter of 200 μm and a numerical aperture of 0.22 by using beam shaping and wavelength beam combination technologies.Then,an achromatic lens was used to collimate the dual wavelength laser output from the optical fiber and the other achromatic lens which could move along principal axis and consequently change the spot size was used to focus the dual wavelength laser to the eardrum.Meanwhile,laser and imaging lights were coupled as coaxial by using a hot mirror and the imaging components from markets.Moreover,the location of myringotomy could be piloted by red light on a computer monitor.According to the results of measurement,the laser power output from the system can be continuously adjusted from 0 to 13.3 W,and the spot size can also be adjusted between 1-3 mm.The system can decrease the operation time and the possibility of surgery side effect;moreover,the myringotomy for children needs not any anasthesia.In addition,the system has the virtues of low volume,light weighted and high wall-plug efficiencies compared with other candidates.

A hundred-watt level semiconductor laser air cooling system was analyzed by ANSYS finite element analysis software.The temperature distribution and air cooling system of this high-power semiconductor laser module were simulated and optimized.It provides the basis of the choice program for 100 W-class high-power semiconductor laser module air cooling technology,and the relative experiment has been verified.

As 808 nm single emitter diode lasers have low output powers,they are limited to pump neodymium-doped double-cladding fiber lasers in end pumping.In order to enhance the pumping efficiency of the fiber laser by using single emitters,a fiber coupled module with several single emitter diode lasers was developed.First,the fast axis and slow axis of each diode laser were collimated by a micro-lens.Then,the output beams of diode lasers were combined with reflecting prisms.Finally,a suit of optical system designed by ourselves was utilized to expand and focus the beam into a optical fiber.Experiments show that this approach can greatly increase the brightness of the module with fiber coupled LDs.Four LDs with continuou output power of 5 W are coupled in a 105 μm multimode optical fiber with a core diameter of 105 μm and a numerical aperture of 0.2 when the working current is 5.8 A,it can offer the fiber output power of 15.22 W,coupling efficiency of 74% and the brightness over 1.4 MW/cm2·sr.

A kind of beam shaping technique was presented to improve the beam quality of a semiconductor laser and to achieve the beam splitting,translating,and rearranging by a parallel plate glass stack.The experiment uses a 20-layer 808 nm semiconductor laser array designed by ourselves with the output power of 60 W per bar,19 light-emitting points of 1 μm×135 μm each and 30% filling factor to expand beam at a slow axis through a telescope system,and also uses a focusing lens to focus on both the slow axis and the fast one at the same time.Experiments show that the technique can achieve the 1 kW output power on the focal plane,focused spot of 1 mm×1 mm and coupling efficiency of 90%,which basically satisfies the needs of laser cladding and welding.