Recent Developments in Optoelectronic and Spectroscopic Techniques at Queen’s University, Belfast

Abstract

Recent developments of the fixed gap, spherical mirror confocal Fabry-Perot interferometer for time resolved high resolution laser spectroscopy, including the measurement of spatial coherence, are described and illustrated with an interferogram of a pure single mode giant pulse ruby laser of 4 × 10⁸ mW/cm²/sr brightness. Applications of a new multiple-beam image tube framing camera, producing up to ten consecutive frames on a nanosecond time scale, are discussed together with limitations arising from photocathode saturation in single stage image tube streaking and framing cameras. Properties of dye lasers, including spectral narrowing to a single longitudinal cavity mode and mode locking, are reported, and a simple coaxial linear pinch flashtube pumped dye laser system is described. A direct measurement of an optical frequency Stark shift of the 7699-Å potassium resonance line has been obtained employing a ruby pumped dye laser as a background continuum source, and subpicosecond pulses from a Nd in glass relaxation oscillator have been measured.