Parts and Functions of a Light Microscope (Part II)

A primitive microscope was invented in 1590 inlens power. So, if you couple a 10x eyepiece lens
Middelburg, Netherlands, by the eyeglass makerswith a 40x objective lens, the total magnification is
Hans Lippershey, Zacharias Jansen and his fatherof 10 x 40 = 400 times.
Hans Jansen. Further, Galileo Galilei improved the4. Stage clips: hold the slide in place.
instrument by using a set of aligned lenses and called5. Stage: it is a flat platform that supports the slide
it "occhiolino", what means "little eye". In 1625,being analyzed.
Giovanni Faber named Galileo Galilei's "occhiolino" as a6. Diaphragm: it controls the intensity and size of the
compound microscope and this name remains untilcone light projected on the specimen. As a rule of
today.thumb, the more transparent the specimen, less light
The optical microscope, the most common type ofis required.
microscope, contains several parts with specific7. Light source: it projects light upwards through the
functions. Observe the picture and find theirdiaphragm, slide and lenses.
functions.8. Base: supports the microscope.
1. Eyepiece: contains the ocular lens, which provides a9. Condenser lens: it helps to focus the light onto the
magnification power of 10x to 15x, usually. This issample analyzed. They are particularly helpful when
where you look through.coupled with the highest objective lens.
2. Nosepiece: holds the objective lenses and can be10. Arm: supports the microscope when carried.
rotated easily to change magnification.11. Coarse adjustment knob: when the knob is
3. Objective lenses: usually, there are three or fourturned, the stage moves up or down, in order to
objective lenses on a microscope, consisting of 4x,coarse adjust the focus.
10x, 40x and 100x magnification powers. In order to12. Fine adjustment knob: used fine adjust the focus.
obtain the total magnification of an image, you needVisit my blog for the next article: theory and
to multiply the eyepiece lens power by the objectiveapplication of light microscopy.