The deuterium lamp is a specially developed lamp of end-on cylindrical geometry. Emission between 370 and 165nm is continuous, while below 165nm molecular lines predominate and can be emitted by the lamp only if a suitable window such as MgF2 or LiF2 is used. Featuring an emitting area of 1 mm diameter, F/7 is typical, operating current and voltage are 200mA at 70V. This is the only source which has found widespread popularity over this whole region, mainly because it is convenient to use and demonstrates excellent stability.
Until recently, sealing a magnesium fluoride window to glass or metal required the use of either epoxy adhesives or silver chloride, both of which contribute impurities to the spectra of sealed lamps. With the availability of glassblowing techniques for sealing magnesium fluoride windows to glass envelopes (Freeman et. al. 1977, Freeman and More 1978) the possibility of extending the useful range of the deuterium lamp down to 115nm has been exploited. The window is polished magnesium fluoride, cut with its optical axis perpendicular to its face. This type of seal enables the lamp to be used at temperatures up to 300 degrees Celsius.
Over time accumulation of contaminants on the outside surface of the window produces degradation. A small flow of pure argon can be used to buffer the outside surface of the window, with a differential pumping system between the lamp and the vacuum system. With this method there are no observable external window degradation effects. If degradation occurs it is possible to remove the absorbing film by polishing the window with a cotton wool pad soaked in a paste formed by mixing aluminum oxide (0. 05 m grain size) with distilled water.
This lamp is supplied complete with an in line power supply. Size 11 3/8"W x 6 3/8"H x 7 1/8"D.
Optional:
This source is an F/7 - if used in conjunction with optical systems exhibiting other aperture ratios, throughput and collection are not optimized. We have developed an accessory utilizing a grazing incidence first surface refocusing optic. This Model 615 focusing accessory is VUV or UHV compatible and concentrates the energy providing at considerable gain. Specify the F/No. you wish to match when ordering.