MS257 1/4 m Monochromator and Imaging Spectrograph from Newport

The MS257™ is a completely automated, efficient 1/4 m instrument, with enough versatility to satisfy most spectroscopy applications. It is an F/3.9 instrument with a focal length of 257.4 mm, usable as a monochromator or true flat field imaging spectrograph. Stray light is negligible, and there is no re-entrant spectra. The MS257 has 2 output ports, 1 input port (with optional accessory can support 2 inputs), and supports 4 gratings. USB and RS232 are standard. GPIB (IEEE488) communication is available using an external USB to GPIB converter sold separately.


  • 1/4 m monochromator or imaging spectrograph configurations
  • 4 grating turret with automatic grating switching
  • Two flat field output ports with automatic port switching
  • Negligible stray light and no re-entrant spectra
  • USB and RS-232 Communication
  • RS-232 can be configured with optional IEEE-488 (GPIB)

High Efficiency

The low F/number of 3.9 (a numerical aperture of 0.128) combined with slits of up to 5 mm wide x 20 mm high, gives an efficient throughput. The dispersion is similar to that of our other 1/4 m monochromators, and twice that of our 1/8 m systems. The mirrors and gratings in MS257 were designed to further enhance throughput. Each of the optics is uses an aluminum and a magnesium fluoride coating which improves their UV efficiency. (Contact a Sales Engineer for gold coated optics.) The 77708 Multiple Grating Turret allows you to choose up to four gratings to cover your wavelength range.