The use of metal atom active media allows to convert optical signals with the transferring of the adjusted contrast. Due to the opportunities of metal vapor active media it makes possible to increase the intensity of the signal in the narrow spectral range. As a result, the signal-to-noise ratio can be dramatically increased. It makes possible to build active optical systems for high speed imaging of processes which are hidden by high intensive radiation. In the systems is available the image active filtration due to induced transition on metal atoms. Active optical systems with metal vapor brightness amplifiers (which is called Laser monitor), have shown the high efficiency for reducing the background radiation effect on the observing processes in the real-time mode. Moreover, the use of different active media makes it possible to change the spectral contest of the input signal with the increasing of the intensity. In the work the result of the research such systems are presented. The method of transformation IR images to VIS images is discussed. The work presents the results of the using of different active optical systems for high speed imaging.
The intensive development of beam, plasma, discharge and laser technologies makes non-destructive testing methods and devices based on passive and active optical systems. There is an active optical system, which is called a laser monitor. The using of this system makes it possible to form images of test objects and processes suitable for analysis even under background radiation, however, the imaging distance does not exceed 3.3 m. The bistatic scheme of the laser monitor is designed to expand the capabilities of imaging using active media on metal vapors. This paper shows the operation features of the bistatic laser monitor as well as the parameters of the formed images. One of the issue is to compare the amplification of image brightness in an optical converter due to the different laser monitor scheme modification.
The paper presents the results of the experimental study of a copper bromide vapor active medium operation in the amplified spontaneous emission (ASE) mode with the pulse repetition frequency (PRF) up to 200 kHz. The oscillograms of the active medium radiation pulse at various frequencies in a generator (lasing) mode, single-pass amplification mode and ASE are presented. The possibility to use active media on self-terminating transitions as brightness amplifiers at PRFs higher than 100 kHz has been shown.
This work describes an experimental study of obtaining the amplified spontaneous emission (ASE) on sodium D-lines using nonresonance broadband optical pumping. ASE is observed at transitions D2 and D1 line: 589 nm (32 P3/2 – 32 S1/2) and 589.6 nm (32 P1/2 – 32 S1/2). The active medium was pumped by the dye laser with FWHM of 5 nm, maximum radiation in the range 584.5-586.5 nm, and pulse energy above 2 mJ. The working temperature of the active medium was 260 °С, initial pressure of buffer gas-helium was 300 torr (operating pressure - 500 torr). A change in the absorption spectra at D lines at different temperatures of the active medium and buffer gas pressures was observed
Investigation of the energy characteristics of copper, manganese, lead halide vapor lasers with inner reactor and small active volume 90 cm3 was made. The optimal operating pulse repetition rates, temperatures, and buffer gas pressure for gas discharge tubes with internal and external electrodes are determined. Under identical pump conditions, such systems are not inferior in their characteristics to standard metal halide vapor lasers. It is shown that the use of a zeolite halogen generator provides lifetime laser operation.
The paper presents the history of active optical systems development from a laser projection microscope to a laser monitor. The examples of object visualization and diagnostics of high speed processes hidden by the intense background radiation are discussed. These are the processes of laser-surface interaction, self-propagating high-temperature synthesis (SHS), the corona discharge in the air, the nanoparticle production process using a high-power fiber laser, and etc. The results obtained by different research groups suggest that high-speed metal vapor brightness amplifiers and active optical systems based on them need further research, development and novel applications.