X-ray tube target interaction pt 4 (Xray process )

What happens when the rotor or prep button is activated on the x-ray tube?

It begins preparing the tube for exposure by heating the filament and spinning the anode.

What happens on the cathode side during tube preparation (Step 1)?

The filament current heats up the filament.

What happens on the cathode side during tube preparation (Step 2)?

The heat boils electrons off the filament through thermionic emission.

What happens on the cathode side during tube preparation (Step 3)?

The electrons gather in a cloud around the filament, forming the space charge.

What happens on the cathode side during tube preparation (Step 4)?

The negatively charged focusing cup keeps the electron cloud tightly focused together.

What is the space charge effect?

The limit on the number of electrons that can be emitted from the filament because of repulsion from the electron cloud.

What happens on the anode side during tube preparation?

The rotating target begins to spin rapidly, quickly reaching top speed.

What is the purpose of spinning the anode before exposure?

To allow for heat dissipation and prepare for the incoming electron stream.

What happens when the exposure (exposure button) is initiated?

The high voltage is applied, causing electrons to move rapidly from the cathode to the anode.

What happens on the cathode side during x-ray exposure (Step 1)?

A high negative charge strongly repels the electrons.

What happens on the cathode side during x-ray exposure (Step 2)?

The electrons accelerate across the tube toward the anode, forming the tube current.

What happens on the anode side during x-ray exposure (Step 1)?

A high positive charge attracts the electrons in the tube current.

What happens on the anode side during x-ray exposure (Step 2)?

The high-speed electrons strike the anode target.

What happens when the electrons strike the anode target?

Their kinetic energy is converted into x-rays and heat.

What percentage of energy is converted into x-rays during exposure?

Approximately 1% of the electron energy is converted into x-rays; the rest becomes heat.

What is the purpose of the tube current?

It represents the flow of electrons from cathode to anode during exposure.

Why must the anode rotate at high speed during exposure?

To distribute the heat over a larger area and prevent damage to the target.

What are the two main products of x-ray exposure?

X-rays and heat.