When viewing through a compound microscope, our eyes should be positioned not on the eyepiece, but a short distance away from it for best viewing . why ? How much should be that short distance between the eye and eyepiece?

Explanation

The image of the objective in the eye-piece is known as eye-ring.. All the rays from the object refracted by objective go through the eye-ring. Therefore, it is an ideal position for our eyes for viewing. If we place our eyes too close to the eye-piece, we shall not collect much of the light and also reduce our field of view. if we position our eyes on the eyering and the area of the pupil of our eye is greater or equal to the area of the eye-ring , our eyes will collect all the refracted by the objective. The precise location of the eyeing naturally depends on the separation between the objective and the eye-piece. When you view through a microscope by placing your eyes on one end. the ideal distance between the eyes and eye-piece is usually built-in the desing of the instrument.