X-RAY GENERATOR CIRCUIT DIAGRAM , PRODUCTION OF X-RAYS AND INTRACTION OF X-RAY WITH MATTER. THIS PRESENTATION CONSISTS LOT OF ANIMATIONS YOU WOULD LOVE TO WATCHING IT. JUST DOWNLOAD AND ENJOY

1. ELECTRIC CIRCUIT DIAGRAM OF
X-RAY GENERATOR , PRODUCTION OF X-RAYS and
interaction of x-rays with matter
FAYAZ AHMAD KHAWAJA
RADIOGRAPHER

2. OBJECTIVES
2. Working mechanism of x-ray circuit
1. Basic components of x-ray circuit
3. The exposure timer and automatic expose timer
4. The production of x-rays
5. Interaction of x-rays with matter

3. X-RAY GENERATOR
• An x-ray generator is a device that supplies electric power to
the x-ray tube.
• Most radiology departments have 3 phase power available
in range of 203V to 230V.
• MISNOMER:
• Permits operator to control Kv , mAs and exposure time

4. XRAY TUBE REQUIRES ELECTRIC ENERGY FOR TWO PURPOSE
• To boil the electrons from the filament.
• To accelerate these electrons from cathode to anode.
• X-RAY GENERATOR HAVE CIRCUIT FOR THESE TASKS
AND THESE ARE:-
1. High voltage circuit
2. Filament circuit and
3. Timer circuit for regulating the length of x-ray exposure.

6. WHAT IS CIRCUIT?
• Interconnection between some electric elements is called circuit.
its components are Battery, Wire, Resistor, Capacitor etc.

7. ELECTRIC CURRENT
An electric current is a flow of charged particles, such as electrons or ions,
moving through an electrical conductor or space.
TYPES
ALTERNATING CURRENT
DIRECT CURRENT
Alternating current (AC)
is an electric current
which periodically
reverses direction and
changes its magnitude
continuously with time.
Direct current is one-
directional flow of
electric charge. an
electrochemical cell is
a prime example of DC
power.

8. Magnetic flux is a measurement of the
total magnetic field which passes
through a given area or number of
magnetic lines passing through a
given closed surface
MAGNETIC FLUX
MAGNETIC FIELD
Magnetic field is the region around a
magnetic material or a moving electric
charge within which the force of
magnetism acts.
MAGNETIC FIELD
MAGNETIC FLUX

9. ELECTROMAGNETIC INDUCTION
• Change in magnetic flux in a conductor induces voltage in an near by conductor.
• AC current produces an alternating magnetic field.

10. If suppose the current in the primary
coil changes continuously, then the
induced magnetic field of the primary
coil produces a changing current in the
secondary coil.
ELECTROMAGNATIC INDUCTION
MUTUAL INDUCTION
There are two types of induction process:
SELF INDUCTION
Self inductance is defined as the induction of
a voltage in a current-carrying wire when the
current in the wire itself is changing
SELF INDUCTION

11. Voltage is the pressure from an electrical circuit's power source that pushes
charged electrons (current) through a conducting loop, enabling them to do work
such as illuminating a light. In brief, voltage = pressure, and it is measured in
volts (V).
VOLTAGE

12. TRANSFORMER
TRANSFORMER USES ELECTROMAGNATIC INDUCTIONTOVARYTHEVOLTAGE
• The basic transformer consists of an
iron core , a primary winding circuit and
secondary winding circuit.
• An AC current flowing through the
primary winding produces a changing
magnetic field,
• which permeates the core and
induces an alternating voltage on
secondary coil.

14. TYPES OFTRANSFORMER
There are three types of transformers used in x-ray circuit
1. AUTOMATICTRANSFORMER: Allows the selection
of input voltage to step –up and step-down
transformers. [Incoming voltage 230V,60hz ac]
2. STEP UP TRANSFORMER: provide high voltage to
x-ray tube.[electron acceleration requires b/w
40000 and 150000 volts]
3. STEP DOWNTRANSFORMER : provides high current
to the x-ray tube filament.The incoming line
voltage drops to 5V to 15V and amperage
increases to 3A to 5 A.[Filament heating requires
10V]
Note: Automatic transformer is used
to allows fluctuations in the mains input
voltage to be corrected before the current
is fed to the high tension transformer .

15. CONTD……………
• In a step up transformer the voltage is increased
but the amperage must decrease to keep the
power constant (transformer law i.e. Vs/Vp = Ip/Is
=Np/Ns).
• Step up transformer has a ratio of 1:1000[Np/Ns].
• Converts voltage to kilo voltage.
• Conversely step down transformer will decrease
voltage from the primary coil to the secondary
coil, with a corresponding increase in amperage.

16. AUTOTRANSFORMER
• Voltage supplied to x-ray room is connected
to a x-ray generator through autotransformer.
• Functions:
1. Supplies voltage for x-ray tube filament.
2. Provides voltage for primary coil for
high voltage transformer.
3. Provide a convenient location for Kvp
meter.
• Consist of a single winding wound on a laminated
closed core.
• Works on the principle of self induction
• Self induction: Self-induction is the ability of an inductor
in a circuit to generate inductive reactance, which
opposes a change in the circuit current. when an ac
source voltage rises, and the magnetic flux expands
around the circuit conductors, an opposing voltage, or
counter-voltage, is induced in the circuit.
• THUSWITH AVERY LIMITING
RANGEAUTOTRANSFORMER
CAN ACT AS STEP UP AND STEP
DOWNTRANSFORMER.

17. Thermionic emission (archaically known as the Edison effect) is the flow
of charged particles called thermions from a charged metal or a charged
metal oxide surface, caused by thermal vibrational energy overcoming the
electrostatic forces holding electrons to the surface.
THERMIONIC EMISSION

18. FILAMENT CIRCUIT
• Cathode is heated by current by step
down transformer or low voltage supply.
• Out put is controlled by Ma selector.
• Increasing ma = More heating to cathode
= Increasing temperature =Increased
thermionic emission.
• Two levels of heating of cathode
1. standby heating
2. during exposure heating

19. DIODE: An electric device in which electric
current flows only in one direction.
RECTIFICATION : The conversion of alternating
current (ac) to direct current (dc).
HALF WAVE RECTIFICATION: A half wave rectifier
is defined as a type of rectifier that allows only
one-half cycle of an AC voltage waveform to pass
while blocking the other half cycle.
FULL WAVE RECTIFICATION: A rectifier that
converts the complete cycle of alternating current
into pulsating DC

20. BRIDGE RECTIFIER CIRCUIT
(USED IN XRAY GENERATOR WITH HTT)
The bridge rectifier is a type of full-wave rectifier that uses four or
more diodes in a bridge circuit configuration to convert alternating
(AC) current to a pulsating direct (DC) current.

21. TIMER CIRCUIT
• Control the duration of x-ray exposure.
• Terminates after the present time has elapsed or when
the receptor have received specific level of exposure.
• Operator controls switches and timer turns radiation
on and off.
• TYPES :
1. MANUAL TIMER.
2. ELECTRONIC TIMER
3. AUTOMATIC EXPOSURE CONTROLE(AEC)
Manual and Electronic timer is subjected to human
error. the exposure time is selected on the basis of
thickness and density of part under examination, if
the estimation is incorrect there is improper
radiographic exposure.

22. EARTHING IN XRAY GENERATOR
• Earthing also known as grounding is an essential safety
measure in electrical circuits including x-ray generator
circuit.
• The purpose of Earthing is to provide low resistant path for
the flow of electric current in the event of fault or accidental
contact with high voltage components.
• This helps to protect both the equipment and individuals
from electric shock and potential damage.
• The specific components that are connected to Earthing may
vary depending on the design and manufacturer of the x-ray
generator, but the following are common components that
are often grounded.
(I) X-ray tube housing.
(II) High voltage power supply .
(III) Control unit and user interface.
(IV) Chassis and casing
(V) Collimator and Accessories.
(VI) Exposure switch and safety system.
•

24. X-RAYTUBE

25. ATOMIC STRUCTURE
An atom is the smallest particle characterizing an element.
The present concept of atomic structure is bhor’s model.
The fundamental particles of an atom are proton, neutron and
electron.
Atom consist of central core called nucleus, which is
positively charged.
Nucleus consist of proton & neutron,.
Proton is positively charged and neutron has no charge.
The electrons are negatively charged particle revolving
around in different orbits.

26. BINDING ENERGY AND ELECTRON ENERGY
 BINDING ENERGY
• The energy required to remove an electron from its
orbit.
• Binding energy of inner shell electrons are more
than the outer shell electrons
 ELECTRON ENERGY
• The electron energy is the energy of the particular
electron of an atom.
• Electron energy of outer shell electrons is more than
the inner shell electrons.

27. PRODUCTION OF X-RAYS
• X-rays are produced by energy conversion when fast moving electrons from filament of x-ray
tube interact with the tungsten anode (target).
• Based on the phenomenon of energy conversion , the x-rays are classified into two types:
1. Characteristic Radiation.
2. Bremsstrahlung Radiation.
IN MANY LANGUAGES, X-RADIATION IS REFERRED TO AS
RÖNTGEN RADIATION, AFTER THE GERMAN SCIENTIST
WILHELM CONRAD RÖNTGEN, WHO DISCOVERED IT ON
NOVEMBER 8, 1895. HE NAMED IT X-RADIATION TO SIGNIFY
AN UNKNOWN TYPE OF RADIATION.

28. CHARACTERISTIC RADIATION
• When an accelerated electron having little more or equal
binding energy than the orbital electron of an atom.
• It ejects an electron from the orbit of an atom.
• The atom become ion and unstable.
• The unstable atom try to become stable as soon as
possible.
• To stable the atom electron move from outer shell to
inner shell.
• While moving from outer shell to inner void shell electron
losses its energy in the form of x-radiation(electron energy of
outer shell electron is more than inner shell electron)
• The energy of the x-ray photon is depend upon the
characteristic of the target material we are using.
• Name characteristic come from the fact that the binding
energy of particular shell of an atom is unique for a specific
element.

29. Bremsstrahlung radiation is also called white radiation.
 When an accelerated electron passes nearer the nucleus of
an atom.
 Electrons have negative charge, nucleus of the atom have
positive charge.
 There will be the electro motive force between incoming
electrons and nucleus of an atom.
 The electron is attracted towards the nucleus.
 Due to the attraction the electrons get decelerated and
change their direction.
 Due to deceleration the electron losses its kinetic energy as
a x-ray photon.
The amount of energy lost by incoming electron is depend
upon :
i) How nearer they pass through the nucleus.
ii) The energy of incoming electron
BREMSSTRAHLUNG RADIATION

30. INTERACTION OF X-RAYS WITH MATTER
ATTENUATION : Is the reduction
of intensity of beam as it passes
through medium.
ABSORPTION : Is transfer of
energy from radiation to the
medium.
SCATTERING: Is the change in
the direction of the photon with
or without loss of energy by the
photon

31. INTERACTION OF X-RAYSWITH MATTER
Three possible fates awaits each x-ray
photon while interacting with matter
• Penetration : penetrate section of matter
without interaction.
• Absorption : interact with matter and
completely absorbed by depositing its
energy.
• Scattering: interact and can be scattered
and deflected from its original direction
and deposit part of its energy. No longer
carries useful information because their
direction is random and responsible for
noise in the x-ray image.

32. ABSORPTION AND SCATTERING
There are five different process by which
x-ray may be absorbed or scattered as
they pass through the medium. first three
play a role in diagnostic radiology or
nuclear medicine
1. COHERENT SCATTERING
2. PHOTOELECTRIC EFFECT
3. COMPTON SCATTERING
4. PAIR PRODUCTION
5. PHOTO DISINTEGRATION

33. COHERENT SCATTERING
• Referred by variety of names : Thomson, Rayleigh, classical
and un-modified scattering.
• Name coherent is given to those interactions in which x-ray
photon under go change in direction with out change in wave
length.
• When energy of incident photon(< 10 kev) is less than the
binding energy of strongly bound orbital electron , it may occur.
 In Thomson effect energy of incident photon is absorbed
temporarily by an orbital electron and release after some
time with same wave length but in different direction.
 the same thing occurs in Rayleigh effect but the energy of
incident photon is temporarily absorbed by electron cloud
around the whole atom.
THOMSON
RAYLEIGH SCATTERING

34. PHOTOELECTRIC EFFECT
• The photoelectric effect occurs when an
incident photon has an energy equal to or
greater than binding energy of an electron in
an atom.
• Photon can ionise the atom by ejecting
electron.
• Photon gives all its energy to the atom.
• Vacant site fulfilled by jumping inward from
next shell farther away from nucleus,
accompanied by emission of characteristic
radiation in the form of second photon.

35. COMPTON SCATTERING
• Interaction occurs between photon and
outer shell electron which have negligible
binding energy.
• Electron is ejected from the atom and
photon is scattered with some reduced
energy.
• Scattered radiations from this interaction
is called Compton scatter and ejected
electron as recoil electron.

36. PAIR PRODUCTION
• Don't occur in diagnostic radiology.
• The high energy photon interacts with
nucleus of an atom.
• Photon disappears.
• Its energy is converted into matter in the
form of two particles.
• One is electron and other is positron
(positron : matter with mass as an electron but with +ve charge)
• Cannot take place with photon energy less than
1.02mev.

37. PHOTO DISINTEGRATION
• Occurs with energy more than 10mev.
• Part of nucleus of atom is ejected by a
higher energy photon (excess incident
photon causes instability in nucleus of an
atom thus resulting emission )
• The ejected portion may be neutron , a
proton , an alpha particle or a cluster of
particles.
• The photon must have sufficient energy to
overcome nucleus binding energy of the
order of 7-15 Mev.

38. INTERACTION OF X-RAY RADIATION WITH SOFT TISSUES
XRAY PHOTON ENERGY
RANGE
SITE OF INTRACTION X-RAY PHOTON TYPICAL
INTERACTION
BY PRODUCT OF
INTERACTION
ENERGY DIRECTION
1TO 50 kVp ANATOM UNCHANGED SLIGHTLY
CHANGED
COHERENT SCATTERING NONE
INNER SHELL ELECTRON
USUALLY K OR L
FULLY
ABSORBED
NOT
APPLICABLE
PHOTOELECTRIC
ABSORBTION
PHOTOELECTRON
60TO 90 kVp OUTER SHELL
ELECTRON
REDUCED CHANGED COMPTON SCATTERING COMPTON SCATTERED
ELECTRONAND CS PHOTON
Above 90 kVp
Up to 1.02 MeV
OUT SHELL ELECTRON REDUCED CHANGED COMPTON SCATTERING COMPTON SCATTERED
ELECTRONAND CS PHOTON

39. CONCLUSION
• This presentation has shed light on the fundamental principles behind one of the most critical
imaging technologies in medicine. Understanding circuit diagram is crucial for safe and
efficient generation of x-rays.
• As a radiation worker in medicine understanding the topics covered under this presentation
can offer several benefits . Here are some of the key advantages:
 Safe operation
 Optimising image quality.
 Radiation protection.
 Minimising patient dose.
 Troubleshooting and maintenance.
 Quality assurance
 Artefact recognition.
 Continuous education and research.
 Compliance with regulation
 Effective communication

40. THANKYOU SIR