Synchronization and Power Unit Controller for CO2 Laser Cable Marking System

In this paper, we describe the design of the synchronization and power unit controller (SPUC) for CO2 laser cable marking system inline-processing. It is mainly composed of a synchronization and modulation control circuits. Power control of output laser beam is achieved by pulse width modulation (PWM). The synchronization between the CO2 laser, the rotating mask disk and the pivoting mirror is performed by a Lab VIEW based program and National Instruments (NI).

Numerical investigation of the influence of wavefront distortion on the laser near-field characteristics

The effect of the initial phase distortion of the laser on near-field transmission characteristics in free space is investigated both numerically and theoretically. It is demonstrated and proposed that the near-field modulation and fluence contrast of the output laser beam are changing with the increase of both spatial low- and high-frequency wavefront distortion. The simulation results show that in order to ensure the beam quality in propagation, the Fresnel number should be controlled not <50 generally and the wavefront distortion should also be minimized by controlling both low- and high-frequency phase coefficient not larger than 0.6.

Thermische Resonatoreffekte in organischen Farbstofflasern / Thermal Resonator Effects in Oiganis Dye Lasers

Thermal resonator effects are studied in laser pumped organic dye lasers with the longitudinal pumping arrangement. If the distribution of the pump light is a Gaussion, a diverging lens is induced by the thermal gradient in the dye solution. This thermal lens was compensated by using a suitable resonator set-up with an adjustable telescope. Divergence and bandwidth of the tunable laser were reduced considerably by using the proper compensation. If the angular position of the pump beam is shifted, the axes of laser resonator and thermal lens are different, causing beam deflection and wavelength shifting of the output laser beam. Therefore, high stability and mode purity of the pump laser is important to get a well defined output laser beam.