Describe the construction and working of compound microscope.

Explanation

Construction:
i. Compound microscope consists of two convex lenses called objective (0) and eyepiece (E).
ii. The objective has smaller aperture and smaller focal length as compared to eyepiece.
iii. The two lenses are placed coaxial inside a hollow metallic tube such that the distance between them can be changed.
Working:
i. Any object, which is to be magnified, is placed in front of objective lens.
ii. The image formed by the objective lens acts as an object for the eyepiece as shown in figure.

iii. The image formed by objective is real, inverted and formed at a distance within the focal length of eyepiece.
iv. Hence, the eyepiece forms a virtual, inverted and highly magnified image of the object.
v. As a combined effect of two lenses, higher magnification is obtained in compound microscope. This is used to observe minute object or minute living organisms.