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.
| Features | Benefits |
No need to open the sealed vacuum chamber | Ideal for monitoring sealed vacuum systems |
No electrical feedthroughs | Chamber remains sealed |
| Electromagnetic/Mechanical measurement | Does 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/readout | Electronics remain protected |
High intrinsic accuracy/reproducibility | No adjustments: Sufficient accuracy for most applications |
No electronics remain after measurement | Radiation, Corrosion and “outdoor” weather resistant |
One-button operation | No special training or specialist needed |
| Protection cap and magnet for storage | No breakage risk or damage of the ball's surface |
| Remote PC control | User friendly |
| Serviceable sensor | Quick and easy to clean and reassemble |
| Single connection to multiple units via RS-485 interface | Simultaneously monitors multiple vacuum chambers |