-W ilhelm Conrad Roentgen-1895 -E lectrical discharges in a vacuum tube -C aused a phosphoric screen to fluoresce -F ormed an image of bone -F irst x-ray.

-Wilhelm Conrad Roentgen-1895

-Electrical discharges in a vacuum tube

-Caused a phosphoric screen to fluoresce

-Formed an image of bone

-First x-ray photograph of wife’s hand/ring

One year later British doctors were already using x-ray imaging.

Prolonged exposure to x-rays caused tissue burns.

Wounds were abnormal- took time before appearing.

-The energy of a light-wave is carried by packets called

photons

-The energy of a photon depends on the light’s

wavelength

-Smaller wavelengths have larger energies

1 eV = 1.602x10-19 Joules

Need 56,000,000,000, 000,000,000,000 eV to

cook an egg.

Photon energies are usually given in units of electron

volts (eV)

X-ray tube consists of the following major parts1- Filament: made from tungsten wire which is heated

electrically at a potential difference of 8 to 12 V to a high temperature so that electrons ‘boiled off’ from its surface. These electrons form the tube beam.

The filament is located within a negatively charged nickel cathode which is shaped so that a precise beam geometry is obtained.

2- Cathode: this houses the filament and is manufactured from nickel . The filament is located within a cup having sharp contoured edges which electrostatically focus the electron beam.

The cathode cup is independently supplied with a high negative voltage

3- Anode: is manufacture from tungsten (high melting metal). Dental units and small mobile X-ray units use stationary or fixed anode design. The most efficient design however uses a rotating-disk anode which enables higher X-ray output owing to more effective cooling.

X-ray Image

Two Forks,

Ball pin,

and teeth brush in

the intestine