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Spectral Coverage: approximate, use for reference purpose only
Use 68 x 84mm Grating: When operating at high wavelengths (high grating angles).
The 68 x 84 mm grating preserves the light collecting power (aperture Ratio)
Center Wavelength to High: Refers to the mechanical rotation capability (not the operating or optimum range) of a grating drive. Lower the central wavelength or select a grating that allows operation over your required wavelength region.
CCD Resolution (FWHM): Refers to the resolution available with the selected detector or image intensifier.