The correct answer is: A. Primary emission
A storage oscilloscope is a type of oscilloscope that can store a waveform on its screen for a period of time. This allows the user to view the waveform in detail, even if it is too fast to be seen with the naked eye.
Storage oscilloscopes work on the principle of primary emission. This means that they use a cathode ray tube (CRT) to generate an electron beam. The electron beam is then deflected by an electric field to create an image on the screen.
The image on the screen is stored by a layer of phosphorescent material. This material glows when it is hit by an electron beam. The longer the electron beam hits the material, the brighter the glow.
This allows the user to view the waveform for a period of time, even after the electron beam has been turned off.
The other options are incorrect because they do not describe the principle on which storage oscilloscopes work.
- B. Deflection is the process of bending an electron beam. This is done by applying an electric field to the electron beam.
- C. Secondary emission is the emission of electrons from a surface when it is hit by an electron beam.
- D. Diffusion is the movement of particles from an area of high concentration to an area of low concentration.