Design of optical system for diode laser myringotomy

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.