Physics Lab Equipment

LEEI-21 Electron Beam Demonstrator

LEEI-21 Electron Beam Demonstrator


  • Ideal apparatus for demo

  • Low price

  • Easy to use


This electron beam demonstrator uses a gas-filled cathode-ray tube for electrostatically controlled beam deflection. When the electrodes in the tube are supplied with voltage, a beam of electrons emitted from the cathode is visible due to the illumination of the ionized inert gas impacted by the electrons. This apparatus can be used to demonstrate the following:


1. Hot electron emission phenomenon

2. Rectilinear path of accelerated electrons in the absence of an external electric or magnetic field

3. Deflection of an electron beam within an electric field

4. Lorentz force exerted on an electron beam within a magnetic field


We also supply an advanced model (LEAI-47) for quantitative measurement of electron beam movement in electric and magnetic fields, and for the determination of the e/m ratio of an electron.

Parts and Specifications

Voltage of acceleration electrode0 ~200 V continuously adjustable
Voltage of deflection plate0 ~40 V continuously adjustable
Voltage polarity: positive upper-plate, off, positive lower-plate
Power consumptionApproximately 8 W
Dimensions210 mm × 140 mm × 210 mm
WeightApproximately 1.5 kg
Copyright © Lambda Scientific Systems, Inc. 2010-2019. All rights reserved.