A fluorescence image detection system that can visualize the COIL hot mixing
flow field by taking images of the fluorescence of active I2 with a high speed camera
was set up. Based on the captured flow field image, O2(a1Δ)/I2 mixing quality was
evaluated quantitively by an exclusive image processing program. With this method,
the hot supersonic mixing flow field in COIL which uses parallel stream supersonic
mixing nozzles with a set of trip tabs was investigated. Meanwhile the effectiveness
of the trip tabs was demonstrated.
The light deflector is one of the key components in laser scanning and imaging system, such as rotating holographic gratings, galvanometric mirrors, acoustooptical scanners and rotating polygonal scanners, etc. Of these scanning elements the most commonly used scanner is rotating polygonal scanner. This paper will first briefly discuss the operating principle of rotating polygon and two different polygon scanning configurations: a post-objective scanning scheme and a so-called pre-objective scanning scheme using flat-field scan lens (f-theta scan lens). The emphases will be put on the analysis of the relationship between scanning error and some important error factors of polygon used in the pre-objective scanning scheme. A set of formulae are developed to calculate the tolerance of polygonal reflecting surface, divided angle, the degree of malalignment between reflect surface and the axis of rotation and rotating speed error etc. It provides a reliable foundation for the constitution of the tolerance polygon and rotating speed.