2013 R&D 100 Winner
Princeton Instruments' IsoPlane SCT-320 SpectrographImaging spectrographs are optical instruments used to disperse and sharply focus light in the plane of dispersion, typically the horizontal or tangential plane of the instrument, onto a focal plane array detector. Modern commercial spectrographs typically combine one or more curved optical elements, whether reflective mirrors or refractive lenses, which collimate light to and focus dispersed light from a dispersive element onto a focal plane array detector.

Princeton InstrumentsIsoPlane SCT-320 Spectrograph eliminates the primary aberrations present in traditional imaging spectrographs. As a result, more photons end up in spectral peaks, increasing the effective signal-to-noise ratio (SNR). Traditional Czerny-Turner imaging spectrographs are subject to imaging aberrations such as coma, astigmatism and spherical aberration. Coma limits the spectral resolution of a spectrograph at most wavelengths, as it can be eliminated at only a single grating angle. The IsoPlane SCT-320 reduces coma, preserving spectral resolution at all wavelengths. It also removes astigmatism. This means that many more fibers in a bundle can be resolved, eliminating crosstalk in multichannel spectroscopy. Other notable features are the large f/4.6 aperture, a motorized triple-grating turret and an ultrastable mechanical design.

Czerny-Turner imaging spectrograph

Princeton Instruments

Development Team

Princeton Instruments' IsoPlane development team members (l-r): Llyod Wentzell, Dina Fagundes-Newcombe, William Asher, Paulo Goulart, Jason McClure, Michael Case.


The IsoPlane SCT-320 spectrograph Development Team from Princeton Instruments
Jason McClure, Principal Developer
William Asher
Michael Case
Robert Fancy
Paulo Goulart
Robert Jarratt
Lloyd Wentzell