Model 218 Spectrometer

Model 218, 0.3 Meter, Plane Grating Scanning Monochromator, aluminum mirrors (U.S. Pat. 3409374), effective aperture f/5.3, consisting of a vacuum tight aluminum housing, focusing mirror and mount, collimating mirror and mount. Bilaterally adjustable entrance and exit slit assemblies. "Snap-In" grating holder (U.S. Pat. 3433557) to accept 50 mm. x 50 mm. gratings. All optics have high reflectance aluminum coating. MgF₂ overcoat is suggested for use in the vacuum ultraviolet. Wavelength counter accurate to ±l Å Completely assembled and factory adjusted.

Specifications

Focal Length	0.30 meter
Angle Between Entrance and Exit Beams	44 degrees
f / No.	5.3
Wavelength Range	105 mm to 60 um
Wavelength Accuracy	+/- 0.1 nm (with 1200 G/mm grating)
Wavelength Reproducibility	+/- 0.005 nm (with 1200 G/mm grating)
Grating Ruled Area	50 mm x 50 mm
Camera Attachment Accepts	35 mm film cut 16 mm long

Performance

Grating (G/mm) (others available)	2400	1200	600	300	150	75	50	20
Wavelength Range from 105 nm to	500 nm	1.0 um	2.0 um	4.0 um	8.0 um	16.0 um	24.0 um	60.0 um
First Order Littrow Blaze	150 nm	150 nm	150 nm	1.0 um	2.0 um	8.0 um	18.0 um	45.0 um
	300 nm	200 nm	300 nm	2.0 um	6.0 um	12.0 um
		300 nm	500 nm	3.0 um
		500 nm	1.0 um
		750 nm	1.6 um
Resolution (nm) at 313.3nm	0.03	0.06	0.12	0.24	0.48	0.96	1.44	3.6
Dispersion (nm/mm)	1.3	2.6	5.3	10.6	21.2	42.4	63.6	159
Wavelength Range at Focal Plane (nm)	20	40	80	160	320	640	960	2400

McPherson, Inc.