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We describe the development of an optical and an X-ray streak camera with picosecond time resolution. The entire peripheral electronics and testing systems have been developed indigenously. Both the streak cameras provide ~ 15 ram/1 ns streak rate with a sweep voltage of ~ 1 kV amplitude and rise time of 1 ns. The time and spatial resolution of the optical streak camera have been found to be ~ 17 ps and 100 #m respectively. The sweep pulse generator developed for this purpose provides a step pulse of rise time ~< 1 ns and amplitude ~ 2 kV. The laser diode used for testing the optical streak camera provides multiple pulsation when the pump current is increased beyond a critical threshold.

A compact low-power long-life sealed-off cw CO2 laser has been developed by incorporating a catalyst-coated outer jacket that helps to regenerate CO2 from the dissociation products formed during discharge. Maintaining the catalyst at an optimized temperature prevented CO2 adsorption in its bulk and resulted in the required level of CO oxidation activity. The laser system has been operated during the day for the past five months at a constant output level of about 4 W. The gas analysis performed at different catalyst temperatures suggests that although the presence of CO in large amounts is detrimental, an optimum concentration of carbon monoxide supports the CO2 laser operation.

A simple and reliable technique to temporally shorten a multinanosecond Nd:glass laser pulse to less than nanosecond duration at the second harmonic wavelength is described in this article. Using this technique a short probe pulse synchronized with the main laser was generated for optical probing of laser-produced plasmas. Experiments reported were conducted with a Nd:glass laser of wavelength 1.06 pm and of 20 ns duration to yield a temporally shortened pulse of duration less than a nanosecond at a wavelength of 0.53 pm. This technique would be particularly useful and give better results for shorter wavelength lasers (UV and VUV) for which the conventional techniques of pulse slicing are sophisticated as well as add to the expense and complexity of the laser system.

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