Presentation about microscopes

1. Microscopes
(Timeline)

2. Dephinition
1. An optical instrument that uses a lens or a combination of lenses to produce
magnified images of small objects, especially of objects too small to be seen
by the unaided eye.
2. An instrument, such as an electron microscope, that uses electronic,acoustic,
or other processes to magnify objects.
3. A device that produces a magnified image of objects too small to be seenwith
the naked eye. Such objects are thus called “microscopic.”

3. Dephinition
The microscope is widely used in medicine and biology.
Common microscopesuse lenses; others, such as electron
microscopes, scan an object withelectrons, x-rays, and other
radiation besides ordinary visible light.
is an instrument with lenses which is used to make really small objects
look bigger by magnifying them.
The tool used by scientists to look at really small bacteria that they need
to magnify is an example of a microscope.

4. Timeline of microscope
(Microscopes in order)

5. First microscope
2nd Century BC - Claudius Ptolemy
described a stick appearing to bend
in a pool of water, and accurately
recorded the angles to within half a
degree.
1st Century - Romans were
experimenting with glass and found
objects appeared larger when viewed

6. Second microscope
12th Century - Salvino D'Armate from Italy made
the first eye glass, providing the wearer with an
element of magnification to one eye.

7. Third microscope
1590 - Two Dutch spectacle makers, Zacharias
Jansen and his father Hans started experimenting
by mounting two lenses in a tube, the first
compound microscope.

8. Fourth microscope
1609 - Galileo Galilei develops a
compound microscope with a convex
and a concave lens.

9. Fifth microscope
1665 - Robert Hooke's book called
Micrographia officially documented a
wide range of observations through the
microscope.

10. Sixth microscope
1674 - Anton van Leeuwenhoek used
his knowledge of grinding lenses to
achieve greater magnification which he
utilised to make a microscope, enabling
detailed observations to be made of
bacteria.

11. Parts of a modern
microscope

12. Parts of a
microscope
Eyepiece Lens: the lens at the top that you look through.
They are usually 10X orTube: Connects the eyepiece to
the objective lenses
Arm: Supports the tube and connects it to the base
Base: The bottom of the microscope, used for support
15X power.

13. Parts of a
microscope
Illuminator: A steady light source (110 volts) used in place
of a mirror. If your microscope has a mirror, it is used to
reflect light from an external light source up through the
bottom of the stage.
Stage: The flat platform where you place your slides.
Stage clips hold the slides in place. If your microscope has
a mechanical stage, you will be able to move the slide
around by turning two knobs. One moves it left and right,
the other moves it up and down.
Revolving Nosepiece or Turret: This is the part that
holds two or more objective lenses and can be rotated to
easily change power.

14. Parts of a
microscope
Objective Lenses: Usually you will find 3 or 4 objective
lenses on a microscope. They almost always consist of
4X, 10X, 40X and 100X powers.
Rack Stop: This is an adjustment that determines how
close the objective lens can get to the slide.
Condenser Lens: The purpose of the condenser lens is
to focus the light onto the specimen.
Diaphragm or Iris: Many microscopes have a rotating
disk under the stage.