anode angle and line focus principle

Question 1

what is the usual anode angle

Answer 1

between 16 and 20 degrees

Question 2

why is the anode angle imnportant

Answer 2

it allows the filament electrons to access the focal track of the anode unimpended

it allows the photons a free exit pathway

it allows image sharpness and heat production to be balanced

Question 3

what is the focal point

Answer 3

thr source of the xrays

Question 4

explain the line focus principle

Answer 4

due to the fact that the focal point is not a point source but much larger we get penumbra which are areas of unsharpness around our image.

so the focus spotneeds to be as small as possible to reduce image unsharpness
.

however tyhe focal spot needs to al;so be as large as possible to spread out the heat produced and we cannot have bothe

to combat this issue we use the anode angle which allows for a larger focal area to be used for heat spread while making it apper as if the xrays are coming from a smaller focal area.

Question 5

what is the anode heel effect

Answer 5

having an anode angle causes the anode heel effect

this is where the bema on the anode side has to pass through thicker tungsten than on the cathode side meaning the beam intesnity on the anode side is less intense.