Question

1. If the field size under a 100x magnification is 0.1 mm in diameter, what would it be under a 40x magnification? Show the calculation.  

2. How about a field size of 0.12 mm under a 10x magnification, what would the field size in mm be under a 400x magnification? Show the calculation.  

Answer 1

1. Field size = Eyepiece field number /M(ob)

M(ob) -Objective lens magnification.

Thus ,Field size (low magnification) X Magnification (low) = Field size (high magnification) X Magnification (high)

Field size (low magnification in mm) X 40 =  0.1mm X 100

  Field size (low magnification in mm) = 0.1 X100 / 40 = 0.25

2.Field size (low magnification) X Magnification (low) = Field size (high magnification) X Magnification (high)

0.12 X 10 = Field size (high magnification) X 400

Field size (high magnification) = 0.12 X10 /400 = 0.003