Transcript PowerPoint

Circa 1000AD – The first vision aid was invented
(inventor unknown) called a reading stone. It
was a glass sphere that magnified when laid on
top of reading materials.
Circa 1284 - Italian, Salvino D'Armate is credited
with inventing the first wearable eye glasses.
1590 – Two Dutch eye glass makers, Zaccharias
Janssen and son Hans Janssen experimented
with multiple lenses placed in a tube. The
Janssens observed that viewed objects in front
of the tube appeared greatly enlarged, creating
both the forerunner of the compound
microscope and the telescope.
A Dutch spectacle-maker
associated with the invention
of the first optical telescope
while trying to find a way to
make magnification even
greater, to help people with
seriously poor eyesight.
Jansen is sometimes also
credited for inventing the
first truly compound
An English natural
philosopher and architect.
 When Hooke viewed a thin
cutting of cork he discovered
empty spaces contained by
walls, and termed them
pores, or cells. The term cells
stuck and Hooke gained
credit for discovering the
building blocks of all life.
Dutch microscopist who
was the first to observe
bacteria and protozoa.
1932 – Frits Zernike invented the phase-contrast
microscope that allowed for the study of colorless
and transparent biological materials for which he
won the Nobel Prize in Physics in 1953.
 1931 – Ernst Ruska co-invented the electron
microscope for which he won the Nobel Prize in
Physics in 1986. Electron microscopes make it
possible to view objects as small as the diameter of
an atom.
 1981 – Gerd Binnig and Heinrich Rohrer invented
the scanning tunneling microscope that gives threedimensional images of objects down to the atomic
level. Binnig and Rohrer won the Nobel Prize in
Physics in 1986. The powerful scanning tunneling
microscope is the strongest microscope to date.
The body tube holds the objective lenses
and the ocular lens at the proper distance
The Nose Piece holds the objective lenses
and can be turned to increase the
The Objective Lenses increase magnification
(usually from 10x to 40x)
These 2 clips hold the slide/specimen in place
on the stage.
The Diaphragm controls the amount of light
on the slide/specimen
Turn to let more light in or to
make dimmer.
Projects light upwards through the
diaphragm, the specimen and the lenses
Some have lights, others have mirrors where
you must move the mirror to reflect light
Magnifies the specimen image
Used to support the microscope when
carried. Holds the body tube, nose piece and
objective lenses
Supports the slide/specimen
Moves the stage up and down (quickly) for
focusing your image
This knob moves the stage SLIGHTLY to
sharpen the image
Supports the microscope
Body Tube
Revolving Nose Piece
Low Power Objective Lens
Medium Power Objective
High Power Objective
Stage Clips
Light Source
Eye Piece
Coarse Adjustment
Fine Adjustment
To determine your magnification…you just
multiply the ocular lens by the objective lens
Ocular 10x Objective 40x:10 x 40 = 400
So the object is 400 times “larger”
Objective Lens have
their magnification
written on them.
Ocular lenses usually magnifies by 10x
Stage at
Lowest Point
Diaphragm at
Convex Lenses are
curved glass used to
make microscopes
(and glasses etc.)
Convex Lenses bend
light and focus it in
one spot.
Ocular Lens
(Magnifies Image)
Body Tube
(Image Focuses)
Objective Lens
(Gathers Light,
And Focuses Image
Inside Body Tube)
•Bending Light: The objective (bottom) convex lens
magnifies and focuses (bends) the image inside the body
tube and the ocular convex (top) lens of a microscope
magnifies it (again).
1) Always carry the microscope with two hands…one on the arm and the
other on the base.
2) Remove the cover and neatly fold. Place in a safe spot on your desk.
3) Clean the eyepiece with lens paper. Never use paper towel or tissue.
4) Turn on the light source.
5) Check to make sure the lowest power objective is in place. Make sure the
revolving nosepiece “clicks” into place.
6) Lower the stage to its lowest position using the coarse adjustment.
7) Check to see that the diaphragm is set on the highest setting (5) or open
all the way. It is best to start with all the light possible and reduce if
1) Prepare your slide and fasten it to the stage using the stage clips. Never pull up
hard on the clips…they are spring loaded and will break easily.
2) Make sure the specimen (what you want to look at) is directly over the hole in the
stage where the light comes through.
3) Look through the eyepiece and raise the stage using the coarse (big) adjustment
until your specimen comes into focus. If it isn’t perfectly clear, then raise or lower
the stage ever so slightly until it is. (If you are wearing eyeglasses…you may want
to remove them.)
4) Once the object is in focus, move the slide appropriately to view the exact part of
the specimen you want. Make sure the arrow (pointer) is surrounded by what
you want to see in the next highest power.
5) Without touching coarse or fine adjustment, switch the revolving nosepiece so
the medium-power objective “clicks” into place.
6) Follow steps 3 and 4 again for focusing in medium power.
7) Finally, without touching coarse or fine adjustment, turn the nosepiece so the high-power
objective “clicks” into place. NEVER touch the coarse adjustment anymore!!!!! Don’t
touch anything and look through your eyepiece. (These microscopes are “par-focal” which
means if it is focused in medium power, then it should be focused in the highest power.)
8) If the specimen appears to be “fuzzy” or out of focus, then ever so slightly turn the fine
adjustment away from you first…if that doesn’t work…then turn it slightly towards your
body. NEVER make a full turn or spin the fine adjustment…this ruins the calibration
and is completely unnecessary!
**It is important to keep in mind that the specimens you are looking at are three dimensional
and the fine focus actually helps you to focus “through” the layers of what you are looking
at. You will be frustrated at first but your skills will improve with time. Practice patience!
9) Draw what is required by the teacher or lab. Make sure you label all the necessary parts and
include the name of what you are drawing and the total magnification power.
1) Make sure the lowest power objective is clicked into
2) Lower the stage to the lowest setting using the coarse
3) Remove the slide from the stage. (If you haven’t done
steps 1 and 2…you could damage the microscope or slide!)
4) Turn off the light source and put the cover back on.
5) Clean up the slides as the teacher directs…listen for
specific directions regarding cleaning up the specimens…it
is not the same for each lab.
Clean only with a soft cloth/tissue
Make sure it’s on a flat surface
Don’t bang it
Carry it with 2 HANDS…one on the arm and
the other on the base
Parts of the Microscope SONG