Transcript The Microscope

The Microscope
2014 - 6th Grade Science
Microscope
A microscope is an instrument for viewing
objects that are too small to be seen easily
by the naked eye.
 Micro - means very small.
 Scope - is a device to look at something.
 Uses more than one lens - the image
magnified by one lens can be further
magnified by another.
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Molecular Expressions Photo Gallery
How to Make a Simple Microscope
Get 2 magnifying glasses and a sheet of
printed paper.
 Hold one magnifying glass a short distance
above the paper. The image will look a bit
larger.
 Place the second magnifying glass between
your eye and the first magnifying glass.
 Move the second glass up or down until the
print comes into sharp focus.
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Types of Microscopes
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Compound Microscope
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Containing two or more lenses
Uses light to magnify
High magnification/Low resolution
Most commonly used microscope
$150 - $1,500
Transmission Electron Microscope
(TEM)
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Used to study parts inside cells
Uses electron beams used to magnify
High magnification/High resolution
$50,000
Examples of Magnification
Microscope Lenses
Lens
– Piece of clear material
that has been shaped to
cause light rays to pass
through it to meet or
spread out
 Concave Lens
– A lens that is curved
inward
 Convex Lens
– A lens that is curved
outward
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Microscope Terms
Magnify
– To make an object look bigger
 Reflect
– To throw back light rays that strike a
surface
 Refraction
– The bending of light rays as they pass
through one substance to another
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1. Eyepiece

Where you look
into the
microscope.
2. Body Tube

Light passes from
the objective lens
to the eyepiece.
3. Rotating Nosepiece

The objective
lenses are
mounted in this
part.
4. Objective Lenses

2 or 3 mounted on
the nose piece.
Each one
magnifies a
different power.
5. Arm

This part supports
the entire upper
portion of the
microscope.
6. Coarse Adjustment Knob Focus

This part allows
you to move the
upper portion of
the microscope.
7. Fine Adjustment Knob Focus

Once the object
that you would
like to view comes
into focus; you
use this to fine
tune the image.
8. Slide
A thin piece of glass
where you place a
specimen.
9. Stage

The flat place
under the
objective lens
where you place a
slide for viewing.
10. Stage Clips

These two things
keep the slide
from moving
around on the
stage.
11. Aperture

The opening in the
stage that allows light
through.
12. Diaphragm

This disk under
the stage controls
the amount of
light that passes
through the
aperture.
13. Mirror or Light Source

This provides light
so that it is easier
to see the object
that you are
viewing.
14. Base
Supports the
microscope and is
used to carry it.
 Bottom part of the
microscope.

15. Legs
The mirror or lamp is
located between
these.
 Bottom part of the
microscope.
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Using the Microscope
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When carrying a microscope, grasp the arm with
one hand and put your other hand under the
base. You will NOT move the microscopes in the
lab.
Start by adjusting the nosepiece to the lowest
power objective tube (the shortest one)
Make sure your slide is on the stage.
Looking through the eyepiece, slowly adjust the
coarse adjustment knob until the specimen
comes into focus
Make sure the lens does not hit the slide
Slowly adjust the fine adjustment knob until the
specimen comes into focus
What’s my power?
To calculate the power of magnification, multiply the
power of the eyepiece ocular lens by the power of
the objective lens.
The eyepiece lens usually
has a power of 10 x
10 x 40 = 400
What happens as the power
of magnification increases?
We can see better details with
higher the powers of
magnification, but we cannot
see as much of the image.