Model 234/302 Vacuum Ultraviolet Monochromator / Spectrograph
Model 234/302 Vacuum Ultraviolet Monochromator
  • Aberration Corrected Optical System
  • Ultraviolet Spectral Camera with CCD or MCP
  • High throughput, f/4.5
  • Optional - Multiple Port Versions
  • Optional - Ultra High Vacuum Versions
  • Compact - Rugged - Lightweight - Low cost
The Model 234/302 is a compact, multiple purpose vacuum ultraviolet (VUV) monochromator. It's size (13" x 13" x 10") and low weight (25 pounds) allow this instrument to be fixed to a vacuum plasma physics experiment or to a larger instrument as a predisperser or variable filter. It is available as a VUV scanning monochromator or as a spectrometer / vacuum ultraviolet spectral camera (spectrograph) with microchannel plate or CCD detectors. Multi port flexibility even allow it to be set up as a both simultaneously, scanning monochromator and spectral camera.

The Model 234/302 optical design is based on the Seya-Namioka, simple grating rotation changes the output wavelength. To make use of special grating technologies a 64-degree included angle is used. A 1200g/mm type IV aberration corrected concave grating is used for optimum performance. A variety of diffraction gratings are available for the instrument ranging from 2400 to 300g/mm. The grating rotation is controlled by Model 789A-3 digital stepping drive.

A compact, lightweight design allows users to mount this instrument directly to experimental chambers. By design, the slit assemblies can support the weight of the entire instrument. Model 234/302 is popular for use in systems due to its compact design, high throughput and resolution.

Multiple Ports The Model 234/302 can be supplied with an additional entrance or exit port. Vacuum selectable mirrors are available and useful on systems where two detectors are used.

PDF format Data Sheet for: Model 234/302 Monochromator : Model 234/302 Double : Model 234/302 CCD Spectrograph

Specifications

McPherson Model 234/302 200-mm focal length f/4.5 Monochromator
Focal Length200-mm, modified Seya-Namioka design
Working Distance Between Slits9-inches (229-mm)
Angle between Entrance and Exit Beams64 or optionally 180-degrees
f / No.4.5
Grating Size40 x 45-mm
Wavelength Accuracy+/-0.10 nm (with 1200 G/mm grating)
Wavelength Reproducibility+/- 0.05 nm (with 1200 G/mm grating)
Focal Plane25-mm maximum width, tipped at about 30-degrees
Wavelength Rangerefer to grating of interest for range


Performance of the Model 234/302 with various gratings:
Grating (G/mm) (others available) 2400 1800 1200 600 300
Wavelength Range from about 30-nm to 275-nm 365-nm 550-nm 1,100-um 2,200-um
Resolution (nm) at 313.1-nm 0.06 0.08 0.1 0.2 0.3
Dispersion (nm/mm) 2 3 4 8 16


Modes of Operation
CCD detection / Focal Plane Arrays The Model 234/302 uses aberration corrected gratings that produce a focal plane. It can be used with microchannel plate (MCP) or direct-detection CCD detectors. The focal plane lies at an angle of about 25-degrees from the normal. Contact us to learn how easy it is to set up a deep or vacuum ultraviolet spectral camera. The Model 234/302 offers a clean, contaminant free finish permitting rapid pump down and insuring a clean operating environment.

The VUVaS 1000 arrangement, shown at right, is used for deep UV and vacuum ultraviolet quality control in crystal growing, thin film / filter measurement, detector response / light source testing. Similar vacuum monochromator systems are used to excite phosphors and other luminescent or phosphorescent materials, etc. This instrument also finds use in applications like fusion plasma dignostics and high harmonic generation experiments (HHG.)
Model 234/302 based system, VUVaS 1000

Ultra High Vacuum (UHV) & Contaminant Free The 234/302 is available in clean, all metal sealed versions offering vacuum pressures to 10^-10 torr. Residual Gas Analyzer (RGA) certified before shipment, these ultra high vacuum units offer the lowest contamination levels.

Double Dispersion & Low Stray Light The Model 234/302 is available as a double monochromator. Mechanically linked versions are built for best grating tracking. Existing units can be combined and operated with independent scanning drives. Double monochromators have been built in vacuum (to 10^-6 torr) and ultra high vacuum (all metal sealed) 10^-10 torr versions.


Most of our instruments are used in research. We try to collect the publications of authors which used our instruments in order to provide ideas of applications to our customers. Bellow are few of them: