Laser-Induced Plasma Measurements Using Nd:YAG Laser and Streak Camera: Timing Considerations

Abstract

We describe a streak camera system that is capable of both spatial and spectral measurements of laser-induced plasma. The system is based on a Hamamatsu C4334 streak camera and SpectraPro 2300i spectrograph. To improve the analysis of laser-induced plasma development, it is necessary to determine the timing of laser excitation in regard to the time scale on streak images. We present several methods to determine the laser signal timing on streak images—one uses the fast photodiode, and other techniques are based on the inclusion of the laser pulse directly on the streak image. A Nd:YAG laser (λ = 1064 nm, Quantel, Brilliant B) was employed as the excitation source. The problem of synchronization of the streak camera with the Q-switched Nd:YAG laser is also analyzed. A simple modification of the spectrograph enables easy switching between the spectral and spatial measurement modes.

Data of plasma velocity obtained from Streak image processing of laser-induced breakdown

“…The delay generator (Stanford Re-search Systems DG535) plays a significant role in the streak camera operation. Timing considerations regarding the laser pulse and streak camera synchronization are very important in our measurements Rabasovic et al (2012Rabasovic et al ( , 2019, so we added a photodiode and digital oscilloscope to our experimental setup, Fig. 1.…”

“…Our earlier research of optical emission of plasma was limited so far to analysis of time resolved optical emission spectra acquired by the streak camera Sevic et al (2011); Rabasovic et al (2012Rabasovic et al ( , 2014. To make our study more comprehensive we saw the need for measuring the spatial distribution of plasma optical emission Rabasovic et al (2019) and requirement for easy switching between the spectral and spatial measurement modes of our streak camera system soon became apparent to us. We performed a simple modification of our spectrograph that enables easy switching between the spectral and spatial measurement modes.…”

Study of CsI photocathode performance attenuation in x-ray streak cameras

“…The X-ray streak camera is an important diagnostic instrument to study the implosion dynamics and the implosion compression law in laser-driven inertial confinement fusion (ICF), and to obtain the image of the continuous temporal and spatial variations of the plasma radiation [1][2] . Through the acquisition of plasma radiation X-ray time, space and intensity distribution information, can diagnose the implosion compression process, get the target in the fusion of various basic parameters [3][4] . With the development of China's ICF research, the X-ray streak camera puts forward the time, space, energy spectrum precision diagnosis [5][6] .…”