|Commonly Used Phrases and Terms
two optical paths at the same angle. The compound microscope has two
systems of lenses for greater magnification. The objective lens
provides the primary magnification which is compounded (multiplied)
by the ocular lens (eyepiece). Images produced by compound
microscopes are two dimensional. This type of microscope is used to
study very small specimens and requires the specimens to be mounted
on a slide.
Designed with two
separate optical paths with two objectives and two eyepieces to
provide slightly different viewing angles to the left and right
eyes. In this way it produces a 3-D visualization of the sample
being examined. The zoom provides different magnification and
features an inversion system which allows the image to be viewed
normally and right side up. This type features a large stage for
closer viewing of the non-microscopic world like rocks, insects,
flowers, and dissection specimens and does not need to be mounted on
BARSKA’s digital microscopes are
state-of-the-art integration of high quality microscope and a
digital camera. Simply connect the microscope to the computer with
the USB cord to magnify the object and view them on your PC screen
and with option to save. Digital microscopes are great for
educational purposes because several people can view the specimen at
once, unlike a traditional microscope where one person can view at
magnification is calculated by multiplying the magnification of the
eyepiece by the magnification of the objective. 10x(eyepiece) x
4x(objective) = 40x Total Magnification
models allow the user to zoom or change magnification continuously
throughout the magnification range providing a low to high power
range. For example, a 7x-45x microscope has the ability to magnify
the object 7 to 45 times higher than an unaided eye.
WIDEFIELD EYEPIECE (WF)
An eyepiece with an achromatic doublet lens
designed in such a way that it does not have to be limited to
viewing only in its center, and the portion of the lens that allows
non-distorted viewing is larger than a normal lens. This appears to
the user as a bigger aperture or “hole” to look through. It
therefore has the advantage of being easier to use and more
forgiving of a user’s head movements. An eyepiece listed as
WF10X/18mm would indicate it has a widefield achromatic doublet
lens, 10x magnification and is 18mm in diameter
When using a binocular microscope with
interpupiliary adjustment, there is an adjustment for the distance
between the viewers’ eyes. A young child will have a small
interpupiliary distance (IPD) while an adult will have a larger one.
The eyepiece lenses will spread apart or get closer together to fit
refers to the upper part of the microscope that contains the
eyepiece tube and prisms.
Binocular has two
eyepieces, one for each
The third vertical
viewing port can be used with an eyepiece for a second person, such
as an instructor. Or can be used with an adapter for video or still
Transmitted and Oblique
Oblique lighting or top lighting shines
down and reflects off opaque or solid specimens. Transmitted
lighting or bottom lighting shines up through transparent objects.
Not all microscopes will have these types of illumination.
illumination is a simple and inexpensive lighting system that uses
light from an external source (in direct sunlight, lamp etc) and
reflects it upward to the condenser/specimen from a mirror located
below the stage.
illumination provides a cool bright light. Ideal when viewing slides
for long periods or studying live cellular specimens.
illumination provides the very brightest illumination, but tends to
give off heat.
Generally a five-hole disc placed under the
stage on a high power microscope. Each hole is a different diameter.
By rotating it, you can vary the amount of light passing through the
stage opening. This will help to properly illuminate the specimen
and increase contrast and resolution. The diaphragm is most useful
at the higher powers.
This is the distance between the specimen or
cover slip and the objective lens. On compound microscopes that use
slides, the stage is adjustable allowing the user to zoom in or out
of an image. On stereo microscope the stage is fixed.
This is the
rough focus knob on the microscope. You use it to move the objective
lenses toward or away from the specimen. Generally use the coarse
focus first to get close then adjust the fine focus knob for fine
This is the knob
used to fine tune the focus on the specimen. It is also used to
focus on various parts of the specimen.