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 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.)

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 our 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 Length	200-mm, modified Seya-Namioka design
Working Distance Between Slits	9-inches (229-mm)
Angle between Entrance and Exit Beams	64 or optionally 180-degrees
f / No.	4.5
Grating Size	40 x 45-mm
Wavelength Accuracy	+/-0.10 nm (with 1200 G/mm grating)
Wavelength Reproducibility	+/- 0.05 nm (with 1200 G/mm grating)
Focal Plane	25-mm maximum width, tipped at about 30-degrees
Wavelength Range	refer 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

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Focal Plane Arrays The Model 234/302 uses an aberration corrected grating which produces focal plane. It can be used with microchannel plate (MCP) or CCD detectors. The focal plane lies at an angle of about 30-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.

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.

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.