Design, Construction and Characterization of Sealed Tube Medium Power CO2 Laser System

Abstract

A low-cost medium-power carbon dioxide (CO2) laser system is designed, constructed, and characterized to produce coherent, monochromatic laser radiation in the infrared region. The laser cavity is simulated and designed by using ZEMAX optic studio. A switch-mode high-tension pump source is designed and constructed using a flyback transformer and simulated using NI Multisim to study the voltage behavior at different node points. A prototype cooling system/chiller is designed and built using thermo-electric coolers (TEC) to remove the excess heat produced during laser action. Various parameters, such as pumping mechanism, chiller stability, efficiency, output power, and current at different applied voltages, are studied. The chiller efficiency at different output powers of the laser is analyzed, which clearly shows that the chiller’s cooling rate is good enough to compensate for the heat generated by the laser system. The center wavelength of the carbon dioxide laser is 10.6 μm with an FWHM of 1.2 nm simulated in the ZEMAX optic studio. The output beam penetration through salt rock (NaCl), wood, and acrylic sheet (PMMA) at various output powers is analyzed to measure the penetration depth rate of the CO2 laser.

Microcontroller-Based Thermoelectrically Stabilized Laser Diode System

“…The maximum output power of the laser system is around 7.4 mW at a current of approximately 30 mA, as shown in Figure 3(a). If more current is applied to increase the output power, the laser diode crystal gets damaged permanently by current overflow (Naeem et al, 2022a). The graph (Figure 3(b)) shows the variation in the output power and temperature of the laser diode over time when it is operated at some fixed applied current for an extended period with only air cooling.…”

“…The data plotted in Figure 6(a) are recorded when the laser diode was operational to analyze the cooling system efficiency and check that the cooling system is efficient enough to extract the heat and reduce the temperature. The cooling system is efficient enough to control the temperature of the laser diode; as it can be seen from the graph, the microcontroller-based cooling system brings down the temperature of the laser diode from 23°C to the set temperature of 14°C in less than 4 minutes (Naeem et al, 2022a).…”