An electron beam generated by a hot cathode and accelerated to an anode is the physical principle (thermionic emission) that is widely used for a large number of fundamental electronic functions. Depending on how the effect is modulated, an electron beam can be used to generate preliminary x-ray radiation (x-ray tube), sputter material (e beam evaporation), can itself be generated by photons (Photon Multiplier), get to resonance in Magnetrons (Microwave Cyclotron) or even used for imaging (electron microscope).

As electrons would interfere and lose their energy quickly at atmospheric pressure, vacuum conditions are needed to generate a defined flow of electrons (electron beam), typically by hot cathodes that emit electrons and an electromagnetic field that accelerates and guides the beam….

In manufacturing and R&D the SRG can be used to measure the pressure conditions precisely even after the glass cylinder is closed, again using a glass sensor tube that can be removed and disposed of after production.

No need to open the sealed vacuum chamberIdeal for monitoring sealed vacuum systems
Easy to connect to port
No electrical feedthroughsChamber remains sealed
Electromagnetic/Mechanical measurementDoes not affect pressure or gas composition
Insensitive to vacuum process and temperature conditions
All-metal Sensor (in metal or glass tube)Contactless measurement provides long-term stability
High accuracy direct vacuum measurement
No component to fail or replace
Cost effective Sensor concept
Glass sensor tube maybe removed and be disposed of before shipment
Removeable Sensor head/readoutElectronics remain protected
Measurement and mounting on demand
One head for multiple sensors
Heads are universal, fit all sensors
High intrinsic accuracy/reproducibilityNo adjustments: Sufficient accuracy for most applications
Long term stability for years
No electronics remain after measurementRadiation, Corrosion and “outdoor” weather resistant
One-button operationNo special training or specialist needed
Protection cap and magnet for storageNo breakage risk or damage of the ball's surface
Remote PC controlUser friendly
Serviceable sensorQuick and easy to clean and reassemble
Single connection to multiple units via RS-485 interfaceSimultaneously monitors multiple vacuum chambers