Model 632 Deuterium Light Source with Magnesium Fluoride Window for 115 to 380-nm 30 watt, high energy output Easy operation Line operated power supply No flowing gas, coolant or pumps required Beam circular F/7 Fits directly on McPherson slit assemblies Calibrated Deuterium lamps also available

The Model 632 Deuterium lamp is a very popular light source for use with vacuum ultraviolet (VUV) monochromators. It is easy to use, and does not require flowing gas or water-cooling. Emission from 165 to 380-nm is continuous. Molecular emission lines dominate the spectrum below 165-nm. They are emitted through a Magnesium Fluoride window. The lamp has an end-on, cylindrical envelope. This allows maximum distance between the source plasma and window, and longer lamp life. Lamp life is rated at about 1000-hours and usually last considerably longer. The source has an emitting area of 1-mm diameter, and through the window, an aperture f/7 is typical.

Novel glassblowing techniques are used to seal Magnesium Fluoride windows to glass envelope. The window is polished magnesium fluoride, cut with its optical axis perpendicular to its face. This graded glass seal enables the lamp to be used at temperatures up to 300 degrees Celsius. The connection to the vacuum monochromator, or experiment, is made directly at the window.

Over time accumulation of contaminants on the outside surface of the window produces degradation. If degradation occurs it is possible to remove the absorbing film by polishing the window. Active methods can also be considered to slow or stop degradation. For example, a flow of gas and differential pumping can be used to protect the lamp window.

The McPherson Model 632 Deuterium lamp is available as a calibrated standard of spectral radiance. The calibrated Deuterium source is provided with a thorough documentation set describing the measurement set-up and parameters. The measured values are usually presented every 1-nm from 115 to 400-nm. On request, the measurements can also be made at selected, different spectral resolutions. An example calibrated plot and selected data points is provided here.

This lamp is supplied complete with a power supply and all required cables. The housing has an integral passive heat sink and fits directly to the slit assemblies of McPherson monochromators.

The Model 632 source has an f/7 output beam. When it is used with optical systems with different aperture ratios, throughput and collection are not optimized. McPherson developed the Model 615 reflective condenser as an efficient means to aperture (f/no.) match and best fill the optics in your vacuum ultraviolet monochromator, or other experimental system.

Vacuum ultraviolet (VUV) spectrum from the Model 632 Deuterium lamp with Magnesium Fluoride window measured with 200-mm focal length Model 234/302 Monochromator and scintillated photomultiplier Model 658.