Model 247 Grazing Incidence Monochromator for High Resolution Scanning, Microchannel Plate (MCP) intensified, and CCD Array Spectroscopy Experimentation in the Soft X-ray and Extreme Ultraviolet Useful wavelength range 1 to 250-nm (1240 to 5eV) Rapid interchangeability with kinematically mounted gratings Angle of incidence variable from 82 to 88 degrees Wavelength scan and array detection from central image to 250-nm Interchangeable Entrance and exit slits Rowland circle accurate to +/- 4-microns Change of sources and/or detectors without breaking vacuum in main chamber

McPherson Model 247 grazing incidence spectrometer at work at UC Berkeley, Space Science Lab. Many McPherson grazing incidence instruments are used for astrophysics detector calibration and characterization.

Since 1953, McPherson Instruments has pioneered in the design and manufacture of vacuum ultraviolet instrumentation which permits researchers to work effectively in the wavelength region below 300-mn(4.1eV). Until the introduction of the McPherson Model 247 Grazing Incidence Monochromator/Spectrograph, a void existed in the availability of standard commercial instrumentation. Natural crystal X-ray spectrometers are effective from a fraction of an nm to approximately 1.5-nm. Normal incidence vacuum ultraviolet spectrometers are effective from approximately 30-nm through the visible. The Model 247 with its useful wavelength range of 1 to 250-nm closes the gap and provides a generous overlap with existing normal incidence monochromators.

The McPherson Model 247 Grazing Incidence Monochromator is the first universal instrument designed for work in the spectral regions from soft X-ray through the vacuum UV. It is designed on a modular concept. A complete monochromator/spectrograph system consists of a basic module, an optical support table, monochromator attachment, spectrograph attachment, MCP/PDA attachment, vacuum pumping system and a pumping control system. Either the monochromator MCP/PDA or spectrograph attachment may be purchased separately. The grazing incidence configuration for the concave grating is essential for the wavelength range from 1 to 100-nm (1240eV to 12eV).

MONOCHROMATOR MODE Utilizing the monochromator attachment, the Model 247 is an ideal instrument for studies such as ionization and dissociation, where photon energies from 5 to above 1240 electron volts are required. The stepper controlled scanning monochromator attachment covers the wavelength region from central image to 250-nm at the 88 degree angle of incidence with a 300 G/mm grating. The design of the Model 247 allows interchangeability of the entrance and exit slits. Special slits are available for insertion into the ionization chambers of mass spectrometers and special differential slits are available for specific research situations. For light source studies, the stationary slit is normally used as the entrance slit.

MICROCHANNEL PLATE and CCD array MODE For instant interception of 40mm focal plane, a separate traveling chamber that contains microchannel plate and photodiode array camera can be mounted on the Rowland Circle. MCP power supplies and photodiode array data systems with detection speeds up to 250 nanoseconds/pixel are available.

Specifications

Focal Length	2.2-meter, Grazing Incidence design Monochromator / Spectrometer
Grating Size	30 * 50-mm ruled area
f / No.	43
Angle between entrance and exit beams	176 to 150-degrees
Wavelength Reproducibility	0.005 nm (with 1200 G/mm grating)
Vacuum	o-ring seal version for 10^-6 torr, optional all metal sealed versions for 10^-9 torr
Focal Plane	40-mm or 25-mm on scanning carriage for full coverage
Wavelength Range	refer to grating of interest for range

Performance of the Model 247 with various gratings:

Grating (G/mm) (others available)	3600	2400	1200	600	300
Wavelength Range (nm) From <1 to	20.8	32	62.5	125	250
Blaze Angle	holographic	holographic	2deg 4min	1deg 30min	2deg 4min
Resolution (nm)	0.003	0.005	0.008	0.015	0.03
Dispersion (nm/mm)	.01 to 0.05	.011 to .08	.023 to .15	.037 to .30	.064 to .60

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McPherson Model 247M22 Grazing Incidence Spectrometer THE ANATOMY OF A UNIQUE DESIGN The new Model 247M22 is based on McPherson, Inc. and Minuteman Lab's experience of having designed and built hundreds Grazing Incidence Spectrometers. The Model 247M22 has unique features not available in any other design. All of these are included in recognition of newly emerging operating environments for analyzing grazing and semi grazing extreme ultraviolet and soft x-ray spectra. Two of these instruments are in use Max Planck Institute of Plasmaphysik

FEATURES
In vacuum adjustable 89-degree to 86-degree grazing incidence angle while direction of incident beam remains constant In vacuum translatable distance between grating and entrance slit on a straight line towards or away from grating, the same area or event on the same visual axis at all times! Slit can be encoder controlled.

Triple Grating Turret with in vacuum selectable and in vacuum adjustable focus Gratings of different types display considerable tolerance as to radius of curvature (focal distances).

Hinged and in vacuum adjustable Rowland Circle Accurate grazing angles and fine tuning of detector position and focus.

Traveling Micro Channel Plate Intensified detectors Closely adjacent or vertically overlapping intensifier designs insure wide wavelength and contiguous coverage. No lead screws or micro switches etc. in vacuum! Precision positioning via UHV feed throughs to state of the art stepper and encoder control.

Instrument operable in any attitude Remote control of slit width and MCP positions permit operation in inaccessible and hostile environments.

The grazing Model 247M22 can be fitted to the DOUBLE SPRED TOROIDAL MODEL 251D. A combined system of this type, equipped with fast detectors, can provide broad spectral ranges stemming from fast events as encountered in plasma fusion, etc. A unique tool and work horse with all parameters for specific applications can be provided to suit customers' experiments.