N. A. Novoselov

Experimental and computer investigations of slab waveguide rf-excited CO2 laser

Results of investigations of a slab waveguide rf-excited carbon-dioxide laser are presented. Laser output power of range 200 W and efficiency about 10% in a beam with near-diffraction- limit divergence has been achieved. In the repetitive-rate mode, the pulsed power was more than twice as much as the average one in the cw mode. After beam shaping telescope, the total beam divergence of 2 - 3 mrad at the 0.8 power level has been obtained. A codes package of computer simulation of cw slab rf-excited diffusion-cooled carbon-dioxide laser was created. Comparison of calculated and experimental data has been fulfilled.

High-power high-optical-quality rf-excited slab CO2 lasers

For the various pumping rates and for the various heights of the gap were calculated the average value of the small- signal gain and its profile across the gap. For the high power slab CO2-lasers, RF-excited at 40.68 MHz, were analyzed the ranges of their geometry parameters vibration, providing for the possibility of diffraction limited performance. In theory and in experiment was shown the possibility to select the basic waveguide mode of radiation.

Slab waveguide high-power pulsed rf-excited CO2 laser

Slab RF-excited pulsed CO2-laser with the pumping frequency F equals 152 MHz, pulse duration in the range of 20 divided by 50 microsecond(s) , and pulse repetition rate f up to 100 Hz has been investigated. Output power, temporal shape of laser pulses, laser beam divergence were measured at the pumping power up to 400 W/cm3. Pulsed output power was varied in the range of 2 divided by 5 kW. The package of numerical simulation codes of pulse-repetition mode of slab CO2 laser was created. It is shown that the maximum input power is significantly increased by the change of excitation frequency from 80 up to 150 MHz. The measured and numerical data are compared.

Repetitively pulsed slab waveguide rf-excited CO2 laser

Research and development of pulsed-repetitively slab rf- excited carbon-dioxide laser is presented. The experiments were carried out for two modes operation: meander mode (duty factor delta equals 50%) and pulse repetition mode at delta equals 12.5%. The range of 240 divided by 4000 Hz of pulse repetition frequency was used. Pulse power about 400 W for meander mode and up to 700 W for the second mode have been obtained. Input power, radiation pulse shape and output beam divergence were measured.

Slab waveguide rf-excited CO2 laser for material processing

Results of investigations of output power and beam divergence for a slab waveguide rf-excited carbon-dioxide laser are presented. Laser output of range 200 W and efficiency about 10% in a beam with near-diffraction-limit divergence has been achieved. In the repetitive-rate mode, the pulsed power was more than twice as much as the average one in the cw mode. After beam shaping telescope, the total beam divergence of 2-3 mrad at the 0.8 power level has been obtained.

Complex studies of formation and transportation of high-power CO2 laser radiation along a horizontal atmospheric path

In the present paper, theoretical and experimental studies of formation and transportation of radiation of a high-power repetitive pulsed CO2 laser in the optical system and along the 0.5 km horizontal atmospheric path have been performed. As is shown, the use of a light- guide, cooled metallic optics and adaptive system in the telescope provides efficient delivery of the high-power radiation.

New approach to the formation of the basic waveguide radiation mode in a high-power slab-type CO2 laser

The paper presents a new approach for radiation mode formation, based on the proper choice of the discharge electrodes shape and the distance from the resonators mirrors to the butt-end of electrodes. In theory and in experiment was shown the possibility to select the basic waveguide mode of radiation. For 2.5 KW slab CO2 laser, excited at 40,68MHz, was obtained the near diffraction-limited divergence.

RF-excited slab CO 2 laser with intracavity mode selection

The paper presents the new concept for radiation mode selection, based on the spatial filter system, which disposed on the electrode surface of slab CO2 laser. The results of the computer simulation and the experiment are discussed.

Experimental study of small-signal gain and laser beam parameters in high-power pulse-repetitive rf-excited slab CO2 lasers

The paper presents the results of measuring of the small-signal gain in the active medium of the high-power pulserepetitive RF-excited slab C02-laser. The measurements were carried out for the pumping pulse durations in the range 20.50 Ls and pulse repetition rates 100.500 Hz. The maximal specific energy, delivered to the active medium, was 430 W/cm3. In the experiment were measured the average output power of radiation, pulse energy and power and the output beam divergence.

Compact rf-self-excited slab CO2 laser

The compact sealed-off RF-self-excited slab CO2 laser has been developed. The average output power in pulse- repetitive mode of operation is controlled in the range of 20 - 200 W. The maximum pulsed power exceeds 400 W. The divergence of laser radiation is close to diffraction limit. The weight of the laser-head and RF-power supply is in total 40 kg.