SGM stands for spherical grating monochromator, an optical instrument used to select a narrow band of wavelengths from a broadband light source. It uses a single spherical diffraction grating that both disperses and focuses the light, eliminating the need for separate collimating and focusing mirrors. This design is highly efficient for extreme ultraviolet and soft X-ray beamlines where minimizing optical reflections is critical to maintaining beam intensity.
Heard on the job
We need to realign the SGM to get better throughput on the extreme UV beamline.
Insider tip
Because the grating acts as both the dispersive element and the focusing optic, SGMs are notoriously sensitive to alignment errors in the pitch and roll axes.