Analytical design of an Offner imaging spectrometer

• Published in: Optics express Vol. 14; no. 20; pp. 9156 - 9168
• Main Authors: Prieto-Blanco, X, Montero-Orille, C, Couce, B, de la Fuente, R
• Format: Journal Article
• Language: English
• Published: United States 02.10.2006
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/oe.14.009156

We present the analytical design of an imaging spectrometer based on the three-concentric-mirror (Offner) configuration. The approach presented allows for the rapid design of this class of system. Likewise, high-optical-quality spectrometers are obtained without the use of aberration-corrected gratings, even for high speeds. Our approach is based on the calculation of both the meridional and the sagittal images of an off-axis object point. Thus, the meridional and sagittal curves are obtained in the whole spectral range. Making these curves tangent to each other for a given wavelength results in a significant decrease in astigmatism, which is the dominant residual aberration.RMS spot radii less than 5 mm are obtained for speeds as high as f/2.5 and a wavelength range of 0.4-1.0 microm. A design example is presented using a free interactive optical design tool.