Abstract
A high-luminosity-light-collection system for highly spatial detection of chemiluminescence of radical species in flames has been developed. The system, multi-color integrated Cassegrain receiving optics (MICRO) is based upon a Cassegrain-type configuration, which implies that it employs only reflective components (in combination with an optical fiber for light collection). It provides therefore spherical- free and chromatic-aberration-free detection, which is of importance for high-spatial-resolution measurements and for the simultaneous monitoring of signals in different wavelength regions from a given spatial volume. The effective light-collection volume has been estimated to be only 1.6 mm×0.2 mm×0.2 mm by ray-tracing techniques, which is more than three orders of magnitude smaller than that provided by a corresponding simple single-lens system and comparable to that of laser-based techniques, e.g. Doppler velocimetry. The system is also easily aligned since the active probe volume can be visualized by sending in visible light through the system in the reverse direction.
