The vacuum housing and window assembly above the base platform may take on many forms. Castle options are upward extensions of the sample housing which have been designed to accommodate various configurations and application requirements. Castles are designed to provide more room vertically for internal components or to allow external components close proximity to the sample such as for low working distance transmission or external magnets.

castle assemblies

The castle window assemblies may be based on a low profile (window-less) interface layer, onto which specialized housings may be mounted. Alternatively, the castle may be placed above a standard housing. Castle options are often used with the sample chamber extended from the Cryostation. This ensures adequate distance around the sample chamber for use with external equipment.

Standard castle options for the Cryostation 50-class are shown in the table below. Similar castle options also exist for the 100 & 200-class chambers. Please inquire for custom castle requests. 

  Cryostation 50-class Castle Options
Option Round Castle Rectangular Tall Castle Rectangular Tall Castle for Piezos High Numerical Aperture Castle Custom
          design depends on configuration needs
# Optical Ports 1 overhead 2 side, 1 overhead 2 side 2 side Varies
Beam Height n/a 178 mm 178 mm 177 mm Varies
Added Sample Space Height 96 mm 120 mm 114 mm 78 mm Varies
Application Superconducting magnet Low working distance for electromagnet Piezo nanopositioning Transmission Unique experimental requirements


The round castle was designed to integrate external superconducting magnets. There is vertical optical access to the sample. The major sample space components of the round castle option consist of (left to right) 1) the vacuum shroud components, 2) the radiation shield components, and 3) the sample support structure. This castle is shown with the optical gas feed through module installed.



The rectangular tall castle allows for low working distances in a narrow upper housing. As shown below, the module extends the sample space upward to allow close access from all sides of the sample. The module includes two low working distance windows in the horizontal axis, allowing transmission or reflection experiments, as well as a top down window for overhead viewing. The other two sides of the housing have no optical windows, allowing for a thinner housing. This housing allows magnet pole tips to be positioned around the sample with minimal spacing between the pole tips.



This is a special version of the tall rectangular castle that allows XYZ 101 series piezos in the castle itself. This is done to minimize the length of the sample mounting riser and thus minimize vibrations at the sample. See Piezo Positioning Options for more details.



The high numerical aperture castle option can be offered with several variations. Options include adding piezos and/or customizing the castle housing. The installation in the image below has a taller housing because xz piezos are included. The castle can also be offered without the piezos for a shorter housing.


The high NA castle can also be used to achieve closer working distances. The distance from outer window to outer window through the castle is 26.4mm based on 3mm window thickness. The included angle is 88 degrees for an NA of about 0.7, as shown below.

We have the capability to customize the castles for most applications. Please contact us to discuss your specific application requirements.