Translator Disclaimer
2 October 2000 Optical design for an infrared imaging multi-object spectrometer (IRMOS)
Author Affiliations +
The optical design for an Infrared Multiple Object Spectrometer (IRMOS) intended for Astronomical research is presented. To accomplish spectroscopy of multiple objects simultaneous, IRMOS utilizes a Micro- Mirror array (MMA) as an electronically controlled slit device. This approach makes object selection simple and offers great versatility for performing spectral analysis on many objects within a field location. Furthermore, it allows a field location to be imaged without spectra prior to object selection. The optical design of IRMOS has two distinct stages. The first stage reduces an f/15 incoming beam to f/4.5, with a tilted focal plane located at the MMA (the MMA removes some of the tilt of the focal plane, since the micro-mirrors tilt individually). The second stage consists of the spectrometer, capable of resolutions of 300, 1000, and 3000 in the astronomical J, H and K bands. This stage transforms the tilted focal plane into a collimated pupil on a grating, and then re-images onto a HAWAII detector. When used with the Kitt Peak National Observatory 4 meter telescope, a plate scale of approximately equals 0.2 arcseconds per pixel is realized at both the MMA and the detector. A total of 6 mirrors are used, two flat fold mirrors, two off-axis concave aspheres, one off-axis convex asphere, and one off-axis concave biconic mirror. The selection of a biconic surface in this design helped reduce the overall size of the instrument by reducing the size and number of necessary mirrors, simplifying alignment.
© (2000) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Robert S. Winsor, John W. MacKenty, Massimo Stiavelli, Matthew A. Greenhouse, John Eric Mentzell, Raymond G. Ohl IV, and Richard F. Green "Optical design for an infrared imaging multi-object spectrometer (IRMOS)", Proc. SPIE 4092, Novel Optical Systems Design and Optimization III, (2 October 2000);


Back to Top