The Microscope

The History

• Many people experimented with making microscopes

• Was the microscope originally made by accident? (Most people were creating telescopes)

• The first microscope was 6 feet long!!!

• The Greeks & Romans used “lenses” to magnify objects over 1000 years ago.

The History• Hans and Zacharias Janssen of Holland in

the 1590’s created the “first” compound microscope

• Anthony van Leeuwenhoek and Robert Hooke made improvements by working on the lenses

Anthony van Leeuwenhoek1632-1723

Robert Hooke 1635-1703

Hooke Microscope

The History

Zacharias Jansen1588-1631

The “First” Microscope

How a Microscope Works

Convex Lenses arecurved glass used to make microscopes(and glasses etc.)

Convex Lenses bendlight and focus it inone spot.

How a Microscope WorksOcular Lens(Magnifies Image)

Objective Lens(Gathers Light, Magnifies And Focuses Image Inside Body Tube)Body Tube

(Image Focuses)

•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).

The Parts of a Microscope

Body Tube

Nose Piece

ObjectiveLenses

Stage Clips

Diaphragm

Light Source

Ocular Lens

Arm

Stage

Coarse Adj.

Fine Adjustment

Base

Skip to Magnification Section

Body Tube

• The body tube holds the objective lenses and the ocular lens at the proper distance

Diagram

Nose Piece

• The Nose Piece holds the objective lenses and can be turned to increase the magnification

Diagram

Objective Lenses

• The Objective Lenses increase magnification (usually from 10x to 40x)

Diagram

Stage Clips

• These 2 clips hold the slide/specimen in place on the stage.

Diagram

Diaphragm

• The Diaphragm controls the amount of light on the slide/specimen

Turn to let more light in or tomake dimmer.

Diagram

Light Source

• 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

Diagram

Ocular Lens/Eyepiece

• Magnifies the specimen image

Diagram

Arm

• Used to support the microscope when carried. Holds the body tube, nose piece and objective lenses

Diagram

Stage

• Supports the slide/specimen

Diagram

Coarse Adjustment Knob

• Moves the stage up and down (quickly) for focusing your image

Diagram

Fine Adjustment Knob

• This knob moves the stage SLIGHTLY to sharpen the image

Diagram

Base

• Supports the microscope

Diagram

Magnification

• To determine your magnification…you just multiply the ocular lens by the objective lens

• Ocular 10x Objective 40x:10 x 40 = 400

Objective Lens have their magnificationwritten on them.

Ocular lenses usually magnifies by 10x

So the object is 400 times “larger”

Caring for a Microscope

• 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• always carry the microscope holding the arm

with one hand and supporting the base with the other hand.

• Do not touch the lens with your fingers.• Always focus with the low power objective.

• Never lower the coarse adjustment knob when looking through the eyepiece lens

• do not use the coarse adjustment when the high power objective is in place.

• slightly bend the microscope towards you. Do not overbend the microscope.

Carry a Microscope Correctly

Using a Microscope• Start on the lowest magnification• Don’t use the coarse adjustment knob on high

magnification…you’ll break the slide!!!• Place slide on stage and lock clips• Adjust light source (if it’s a mirror…don’t stand in front

of it!)• Use fine adjustment to focus

LABORATORY SAFETY

• Personal safety

always ask permission to the laboratory incharge/teacher before performing the activities.

always wear googles.

never run or play in the laboratory

room.

know the fire alarm,first aid kit,telephone area,where the ff.are kept.

SAFETY IN HANDLING PLANTS

• Use caution

• do not eat or taste any unfamiliar plants

• if you are allergy with pollen, inform the teacher and do not work with eat.

• wear your mask .gloves and googles

SAFETY IN HANDLING ANIMALS

• Handle the animals with care.if you are bitten or scratched by animals inform your teacher.

• do not use wild animals in the activity.

• Use gloves while handling the animals.

SAFETY IN USING FLAMMABLE AND HOT

CHEMICALS• Turn off heat sources when not in use.• When heating substance in test

tubes,keep it away from yourself and others.

• Use proper procedure• To avoid burns,do not handle heated

glassware directly,use test tubes holder.

GLASSWARE SAFETY

• CHECK GLASSWARE FOR CRACKS

• FOLLOW YOUR TEACHER’S INSTRUCTION

• CLEAN GLASSWARE AND DRY THEM.

SAFETY HANDLING CHEMICALS

• Never dispose any solid or liquids chemicals in the sink.

• Use proper container for chemicals

• Never handle chemical with bare hands

• Keep your hands away from your face when working with chemicals

• Never taste chemicals into your mouth

• Always clean up spills immediately

THANK YOU

Jalil C. Antecristo,RN,MAN