'A' Level Medical Option Questions - X-Rays
Q8.
The figure below shows the design of an X-ray image intensifier. The main components are labelled A to D.

Name each component and state its purpose in the process of image intensification.
A: scintillator crystal(s)/fluorescent screen 
It converts X-ray photons into light photons 
B: photocathode 
Incident light energy on the photocathose releases electrons.
The number of electrons released is proportional to the X-ray intensity 
C: anodes 
They increase the kinetic energy of the electrons by accelerating them towards their positive charge.
The are also positioned to focus the electrons to form an image 
D: fluorescent screen
This converts the kinetic energy of the incident electrons into light photons 
(Total 8 marks)