Monochromator-spectrograph MSDDO1000


Double-dispersion monochromator-spectrograph MSDDO1000 series is designed around the modified Cherny-Turner configuration with the two-level arrangement of optical components to allow dispersion doubling.

With a relatively small size, the monochromator-spectrograph MSDDO1000 series ensures the high resolution typical of instruments with a focal length of 1000 mm.

Model MSDDO1002i and model MSDDO1004i  have astigmatism-corrected optics what makes these devices applicable in multi-channel spectroscopy.

Two pairs of automated gratings turret (model MSDDO1004 and model MSDDO1004i ) provides fast switching of gratings with high repeatability of the set wavelength.

In model MSDDO1001 and model MSDDO1001i a single pair of gratings position holder is used for easy manual switching of gratings.


Optical system

 Optical scheme

two-level arrangement, dispersion doubling

 Wavelength range

185 nm – 60 μm



 Focal length

1000 mm (2 x 500 mm)

 Scanning range (limited by grating rotation angle) 

0 – 1280 nm

 Stray light

1 х 10-8 (20 nm from laser line 632,8 nm)

 Flat field

28 х 10 mm


 Horizontal magnification 


 Vertical magnification  1.11 (for MSDDO1002i and MSDDO1004i)
 Vertical spatial resolution - minimal distance between the edges of two neighboring tracks (in multi-channel spectroscopy)

< 15 μm


 Motor type

micro stepper




0.18 arc seconds


± 1 step

 Max. speed 

10 000 steps/s


 Number of ports

2 input, 2 output

 Output port repeatability (automated mirror)

± 0.01 nm

 Switching time (input port)

4 s

 Switching time (output port)

4 s

Optic (for grating 1200 l/mm, wavelength 546 mm)

 Reciprocal dispersion

0.82 nm/mm


± 0.005 nm

 Spectral resolution
  • PMT

0.013 nm

  • digital cameras (12 µm pixel)

0.017 nm

 Wavelength accuracy

± 0.028 nm

 Average scanning step

0.0014 nm



80 х 70 х 10 mm


About the center of ruled grating surface

 Mounting 1. Automated turret for 2 pairs of gratings
2. Holder for 1 pair of manually changeable grating
 Automated turret for 2 pairs of gratings (MSDDO1004 model and MSDDO1004i model)
Grating repeatability:
  • wavelength

± 0.006 nm

  • vertical image

± 20 µm

 Holder for 1 manually changeable grating (models MSDD1002 and MSDD1002i)
Grating repeatability:
  • wavelength

± 0.05 nm

  • vertical image

± 75 µm



On-board CPU



 External interface



 Overall sizes (LхWхH)

556 х 324 х 340 mm


35 kg

All characteristics were measured for grating 1200 l/mm, slit width 15 µm, wavelength 546 nm.
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