Beam quality

Advances in laser technology now allow for solid-state lasers of high beam quality. These beams may be projected from a much smaller auxiliary telescope, which negates the need for optical switching and completely eliminates any main telescope fluorescence. Solid-state YAG lasers are the most common type of lasers commercially available. These lasers use a crystal as the lasing... 

The first fluorescence correlation spectroscopy experiments were carried out several decades ago,62 64 but the general use of the technique was made possible with the introduction of lasers with high beam quality and long-term temporal stability, low noise detectors, and high-quality microscope objectives with high numeric apertures.58,63 The most common set-up is using a confocal inverted epi-fluorescence... 

Of the four nonlinear crystal types investigated in this paper (figure 20), bulk KNbOs was superior in terms of generated blue average power (11.8 mW) and generated beam quality. KNbOs is also less susceptible to the observed saturation and subsequent decrease in SHG efficiency observed in both waveguide crystals. 

Morgado et al., The Effects of Proton Beam Quality on the Production of Gamma Rays For Nuclear Resonance Absorption in Nitrogen, in Substance Detection Systems, G.L. Harding, R. C. Lanza, and L.J. Myers, Editors, Proceedings SPIE 2092, (1994) 503. 

X13 This was an instrument of similar optical design to XI1, but lacking the variable wavelength facility. In terms of beam quality it had similar advantages and limitations to XI1. The camera was used to introduce a triangular monochrometer (Lemonnier et al., 1978) in place of the old rectangular design. For a detailed desciption see Hendrix et al. (1979). 

We expect direct mass measurements to form an important component of the exotic-nuclei program at TASCC. Indeed, we already hope to upgrade our facilities through a proposal made in collaboration with the University of Manitoba to build a high-transmission mass spectrometer, which could accept beam from the ISOL directly without reionization, again making use of the ISOL s excellent beam quality. This could improve the precision of measurements to a level rivalling that now possible with stable isotopes. 

The surface accuracy of commercial mirrors is typically A/5-A/15 at 633 nm, which corresponds to A-3A wavelengths in the XUV/SXR regime. Therefore, the focused intensity together with the focusability is limited by the quality of the curved mirrors. In spite of this situation high-order harmonics can be focused down to a micrometer spot size because of the good beam quality and spatial coherence [14-16]. 

Recent advances in solid-state laser systems offer several potential improvements. In particular, tunable optical parametric amplifiers provide tunable pulses with excellent synchronization and beam quality. However, most reported systems produce pulses of <100 fs. Pulses this short are not needed to measure vibrational dephasing in most systems, and they unnecessarily exacerbate the problems of self-focusing and excitation of overtone transitions. A solid-state system optimized for longer pulses has... 

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