Objective and field diameter?

Question

Assume that a 10X objective has a field diameter of 1.0mm. What would be the estimated field diameter of a 50X objective, in MICROmeters?

I would appreciate any help...thanks :)

Answer 1

Hi,
The field of view is approximately inversely proportional to the objective magnification. So, we can write this:
Ph/Pl =Fl/Fh (Where Fh = field of high magnification and Fl is the low magnification.)

50/10 =1/ Fh
50 Fh =10
Fh = 1/5 mm
= 0.2 mm
= 200 micrometers
(To get micrometers from millimeters, multiply by 1000.)
Incidentally, this is only approximate and if I remember correctly usually overestimates the field size. In actual practice, the size might be more like 180 micrometers.

Hope this helps.
FE