Compound Microscope

Compound Microscope:

For higher magnification, a microscope can be used, which in its simplest form consists of two converging lenses-one of very short focal length called objective and the other of a longer focal length called eyepiece.

The object distance is so adjusted that the image formed by the objective is placed between the eyepiece lens and its focal point, due to which a virtual magnified image is formed by the eyepiece.

Magnification = (magnification of objective) × (magnification of eyepiece)

m = mo × m

Where , mo = magnification by objective

me = magnification by the eye piece

$\displaystyle m_e = (1 + \frac{D}{f_e} )$

and , $\displaystyle m_o = -\frac{v_o}{u_o}$

Hence , $\displaystyle m = -\frac{v_o}{u_o} (1 + \frac{D}{f_e})$