Design, Construction Of Home-built Hollow Copper Cathode Laser & Evaluation of its Usage to Produce Polymers

Abstract

This work presents a new experimental design and construction of a home- made hollow copper cathode discharge laser. A simple constructed power supply is used to provide the discharge tube (Laser Head) with short pulsed current for the purpose of the electrical discharge. The constructed laser is in the visible range, 510.8nm, and operated in a pulsed mode. The energy per pulse is 1.76 mJ, with a pulsed repetition rate of 0.671 KHz. Performance investigations were carried on the electrical characteristics of the hollow copper cathode discharge tube and the results were consistent with the theoretical aspects. An emission spectrometer was used to record the spectrum of the radiation beam emitted from the hollow cathode. Spectral lines were observed in the visible region. The transition line 510.8 nm was isolated through a green filter. It was observed that the intensity of this line is increased with the increasing of current, which gives evidence that this transition is a laser line. The constructed laser was used to irradiate some monomers so as to produce polymer in order to detect the efficiency of this laser in such applications. Samples of monomer was irradiated with the laser for different exposure times, and prepared for spectroscopic measurements. The spectra of the samples, with different irradiation times were collected using infrared spectrometer. The results were compared with other literature, where the source of irradiation is a He- Ne laser (1 mW power, 632.8 nm wavelength). The results shows an obvious advantage of this laser in such application and its efficiency of producing polymer in a short time compared with that of the helium - neon laser