VRS Series Viewport Shutters

Precision-engineered rotary-actuated shutter assemblies designed to protect vacuum system viewports from deposition and contamination during processing. These 90° shutter swing units mount behind “zero height” viewports and provide reliable shielding of the viewport window while allowing quick, positive actuation and locking.

Viewport shutters are used to shield the internal surface of a viewport from coating materials and particulate deposition during vacuum processing, helping to preserve viewport clarity and extend service life. Thermionics’ VRS Series shutters are built for ultra-high vacuum (UHV) performance, robust operation, and flexible integration into vacuum systems.

Key Features

  • Rotary-actuated shutter with 90° swing for full open/close operation behind standard vacuum viewports.
  • FRMC-133-25 rotary feedthrough included — positive mechanical control with no stray magnetic fields and excellent vacuum integrity.
  • All-metal sealed construction with stainless-steel ball bearings for long-term UHV performance.
  • Integrated position lock to secure the shutter open or closed.
  • Shutter cover plate protects >80% of standard viewport area, minimizing deposition on glass.
  • Mounts between chamber and viewport, isolating the viewport from deposition sources.

Typical Applications

  • Shielding viewports during thin film deposition, coating, and sputtering processes.
  • Protecting optical sight glasses in vacuum chambers to maintain visibility and reduce cleaning cycles.

Materials & Performance

  • Body / shutter material: Stainless steel (CF compatible).
  • Vacuum capability: UHV performance when properly installed.
  • Actuation: Rotary feedthrough driven — no pneumatics required in the standard configuration.