Baffle
Deflector plates create electric fields that deflect electrons or other charged particles. A pair of plates is used to which an electrical voltage is applied. The particles are deflected during their movement in the space between the plates by receiving an impulse transverse to their direction of flight through electrostatic attraction during this time .
Deflection system of a Braun tube
Two pairs of plates arranged one behind the other orthogonally around the electron beam form the electrostatic deflection system of a Braun tube .
Deflection plates are used in oscilloscope tubes (Braun tubes) and Vidicon television cameras because the speed of the electrons and the deflection angle are low. With electrostatic deflection, very rapid changes in the deflection angle, i.e. H. achieve very high bandwidths of up to several GHz (see Tektronix SCD5000, 7104 and 7250 (6 GHz bandwidth)).
With picture tubes (tube monitors , tube television sets ), however, deflection coils (electromagnetic deflection systems) must be used because of the higher electron speed and the higher deflection angle . The deflection speeds are lower here; the rate of change of the magnetic fields is limited, the image and line frequency can only be in a certain range (15–30 kHz, depending on the resolution).
Electrostatic distraction in printers
Certain inkjet printers produce a continuous jet of droplets containing electrically charged ink droplets that are scanned horizontally across the paper. A pair of baffles direct droplets into a receptacle as needed while voltage is applied. By switching the voltage on and off, writing on the paper can then be prevented or enabled.
The principle of xerography ( copier ) and laser printers are also based on electrostatic attraction, but no deflection plates are required.