Vacuum Compatible Spectroscopy Accessories

A small collection of accessories we've found useful in assembling systems for spectroscopy in the vacuum regime.

vacuum compatible adjustable slit with ISO NW100K flanges

Adjustable Precision Slit Assembly VUV

Precision bilaterally adjustable entrance slit, micrometer variable width from 0.01 to 3mm. Slit height is variable and may be adjusted from 2 to 20mm when at atmosphere. Has 1/8” NPT accessory port too! Optional built in isolation valve available, inquire. This accessory is o-ring sealed and suitable for vacuum to 10E-6 torr. Port connections are ISO NW100K.

vacuum compatible optical chopper

Optical Chopper Assembly VUV

Clean vacuum chopper assembly with stainless steel housing. It features a 4-slot reflective blade driven by a magnetically coupled transmission. With the provided controller maximum chopping frequency is about 100Hz. The chopper housing provides three beam path ports, one straight through and the other deviating 90 degrees (reflected.) This accessory is routinely used in systems like the vacuum spectrophotometer VUVaS when a correction or feedback signal is required. Vacuum operation in to the 10E-6 torr range. Port connections are ISO NW40KF. Available in all metal sealed UHV version, please inquire.

vacuum compatible polarizer rotator and mount

Polarizer Mount & Rotator VUV

Vacuum polarizer mount allows the user to insert and retract polarizers from the optical axis while under vacuum. The polarizer may also be rotated through more than 90 degrees while under vacuum. Angle readout indicates actual position of the polarizer. Available complete with a Rochon type polarizer, constructed of Magnesium Fluoride and working at wavelengths longer than 120 nanometers. This accessory is o-ring sealed and suitable for vacuum to 10E-6 torr. Flange connections to beam line are ISO NW40KF.

vacuum compatible grating predisperser

Grating Predisperser VUV

To address user needs for coarse dispersion, pre wavelength selection in the vacuum ultraviolet range we conceived this grating predisperser. It is useful in applications requiring low stray light or separation of intense nearby energy from less intense signal of interest. The incidence angle help maintain reasonable optical performance even though this unit most often works with coarse gratings. Vacuum slits are not included but are available as accessories. Some users with simple requirements may use the vacuum compatible grating predisperser as a low performance monochromator or "grating drive" for DIY instrumentation. This accessory is o-ring sealed and suitable for vacuum to 10E-6 torr.

vacuum differential pumping accessory

Differential Pumping Section VUV Data Sheet »

Model DP100 is a high vacuum pump port with a removable conductance limiting aperture. It may be used as a differential pumping section or as a more conventional pumping or gauging tee, gas inlet, electrical feed through, etc. Used as a differential pumping section, the Model DP100 can provide a transition between areas with different vacuum pressure. With a conductance limiting aperture, it creates a transition area between the source’s relatively high pressure and a vacuum spectrometer, or experimental chamber, at lower pressure.

vacuum compatible tip/tilt source alignment accessory

Source Alignment Accessory VUV

The alignment accessory is useful in many applications. For example, in many applications it is important to align, determine field of view, and calibrate spectrometers and detection system. This can be challenging under vacuum conditions. The alignment accessory can also help set optimal light collection from vacuum sources (Deuterium or Hollow Cathode) with respect to emitted source energy. This accessory allows to freely float a source point at the spectrometer's entrance aperture. This enables interception of sections of a hollow cathode plasma, for instance, or, spatial confirmation of peak plasma emission. Useful for any UHV or standard vacuum spectrometer system with 2.75-inch metal sealed flanges or when repeated venting to atmospheric pressure would be required during source alignment. Vacuum operation in to the 10E-10 torr range.

six strut mechanical mounting accessory

Strut Support System Data Sheet »

This strut based mounting system minimizes vibration, and allows easy and precise position adjustment of a wide variety of hardware. It can even work inside high vacuum or ultra-high vacuum (UHV) systems. The six struts provide very solid (seismically adequate) support. When sub millimeter alignment is required, the six-strut system is a proven way of rigidly supporting instruments and fixtures with precise adjustability.

Also read Rigid, Adjustable Support via Six Struts a write up closely adapted from "Rigid, adjustable support of aligned elements via six struts" by W. Thur, R. DeMarco, B. Baldock, K. Rex, Lawrence Berkeley National Laboratory (1997), US-DOE #DE-AC03-76SF00098. There are many ways of adjustable mounting position sensitive hardware. Jack screw and shimming is often troublesome, a drain on manpower and time. Multiple precision stages with capacity for heavy items are very expensive. LBNL’s synchrotron storage ring ALS relies on a simple and cost effective "six-strut" mechanical support system. It meets seismic requirements, minimizes vibration, and allows easy and precise alignment of a wide variety of hardware...