COMPOUND MICROSCOPE

INTRODUCTION

Compound microscopy is an important tool in many sectors, including science, research, medical diagnostics, medicine, engineering, and education.  A compound microscope is built using a mix of lenses and other optical components.Let us go through the concept, lens combination, operating, and magnifying power of the lenses.

CONSTRUCTION

Eyepiece, body tube,objective lenses,stage,condenser,and diaphragm are the most critical components of a compound microscope.

Eyepieces (or) ocular lenses

Eyepiece lenses are to be fastened to the top section of the long vertical body tube, or simply placed near the viewer’s eye and looked through. These lenses are used to magnify the picture produced by the objective lens. Normally, the eyepiece lenses are 10X and 15X. 

Body tube

The body tube connects the eyepiece and the objective lenses.The body tube maintains the optimum distance and alignment of the lenses.

Objective lenses

The primary lenses responsible for magnifying the specimens are objective lenses.Compound microscopes with multiple objective lenses generally have magnification capabilities of 4X, 10X, 40X, and 100X.These objective lenses are attached to the bottom end of the body tube and are generally rotatable. They are usually situated close to the object being seen.

Stage

The object to be enlarged is put on a platform known as the stage.It often has a hole or aperture through which light can travel to illuminate the specimen. The stage may additionally include a mechanical stage for moving the slide or specimen.

Condenser

A condenser is a lens that concentrates light on the item or specimen being observed. 

Diaphragm

It is adjustable and controls the quantity of light that enters the microscope.

There are two lenses  combined in a compound microscope which allows much higher magnification. The compound microscope consists of a long cylindrical tube in which one end of the tube has an objective lens (small aperture and small focal length)  and the other end has an eyepiece lens (the aperture and the focal length are somewhat larger than the objective lens).

Objective lens which focuses a real image of the object,the image is further magnified by the  eyepiece which gives the viewer an image  that is virtual, magnified and inverted concerning the object(AB).

COMPOUND MICROSCOPE-TO GET ENLARGED IMAGE

COMPOUND MICROSCOPE – WORKING

The object (AB) which is to be magnified is placed between the F and 2F of  the objective lens(close to F) in order to get an image (A’B’) of real,inverted and magnified, that is beyond 2F on the other side of the objective lens. (see the image).

The image A’B’ produced by the objective lens acts as an object for the second lens (eyepiece) .The eyepiece  is adjusted so that the object( image of objective lens) lies between  the principal focus and the optic center of the eyepiece lens. (see the second right side image, simple microscope principle).

The image yielded by the eyepiece (A »B »)  is virtual, magnified and inverted concerning the object (AB).

COMPOUND MICROSCPE – MAGNIFYING POWER

SIMPLE MICROSCOPE PRINCIPLE

EYEPIECE ACTS AS A SIMPLE MICROSCOPE :

CONCLUSION

Scientists and researchers have discovered discoveries, solved problems, and improved numerous fields of knowledge using the compound microscope.It has contributed significantly to our understanding of the natural world. The compound microscope will most likely evolve and grow more complex as technology advances. Have you ever looked at enlarged pictures of cells and tissues using a compound microscope?

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