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The Multi-Spectral Imaging system is a new diagnostic that captures simultaneous spectrally filtered images from a common line of sight while maintaining a large étendue and high throughput. Imaging several atomic line intensities simultaneously may enable numerous measurement techniques. By making a novel modification of a polychromator layout, the MSI sequentially filters and focuses images onto commercial CMOS cameras while exhibiting minimal vignetting and aberrations. A four-wavelength system was initially installed and tested on Alcator C-Mod and subsequently moved to TCV. The images are absolutely calibrated and spatially registered enabling 2D mappings of atomic line ratios and absolute line intensities. The spectral transmission of the optical system was calibrated using an integrating sphere of known radiance. The images are inverted by cross-referencing points on TCV with a computer-aided design (CAD) model.

A multi-spectral line-polarization motional Stark effect (MSE-MSLP) diagnostic has been developed for the Alcator C-Mod tokamak wherein the Stokes vector is measured in multiple wavelength bands simultaneously on the same sightline to enable better polarized background subtraction. A ten-sightline, four wavelength MSE-MSLP detector system was designed, constructed, and qualified. This system consists of a high-throughput polychromator for each sightline designed to provide large étendue and precise spectral filtering in a cost-effective manner. Each polychromator utilizes four narrow bandpass interference filters and four custom large diameter avalanche photodiode detectors. Two filters collect light to the red and blue of the MSE emission spectrum while the remaining two filters collect the beam pi and sigma emission generated at the same viewing volume. The filter wavelengths are temperature tuned using custom ovens in an automated manner. All system functions are remote controllable and the system can be easily retrofitted to existing single-wavelength line-polarization MSE systems.