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Diopter adjustment
The adjustment of the eyepiece of an instrument
to provide accommodation for the eyesight
differences of individual observers.
Depth of Focus
The axial depth of the space on both sides of the
image plane within which the image is sharp. The
larger the N.A. of objective, the shallower the
depth of focus.
Field of View (F.O.V.)
That part of the image field, which is imaged on
the observer’s retina, and hence can be viewed
at any one time. The field of view number is now
one of the standard markings of the eyepiece.
Filter
Filters are optical elements that selectively
transmit light. It may absorb part of the spectrum,
or reduce overhaul intensity or transmit only
specific wavelengths.
Immersion Oil
Any liquid occupying the space between the
object and microscope objective. Such a liquid is
usually required by objectives of 3-mm focal
length or less.
Resolving Power
A measure of an optical system's ability to
produce an image which separates two points or
parallel lines on the object.
Resolution
The result of displaying fine details in an image
Total Magnification
The total magnification of a microscope is the
individual magnifying power of the objective
multiplied by that of the eyepiece.
Working Distance
This is the distance between the objective front
lens and the top of the cover glass when the
specimen is in focus. In most instances, the
working distance of an objective decreases as
magnification increases.
X–axis
The axis that is usually horizontal in a two-
dimensional coordinate system. In microscopy X-
axis of the specimen stages is considered that
which runs left to right.
Y–axis
The axis that is usually vertical in a two-
dimensional coordinate system. In microscopy Y-
axis of the specimen stages is considered that
which runs front to back.
