The Microscope

The Microscope Proper Care and Use

Microscopes are an important part of the physician’s office. They are instrumental for diagnosing such things as urinary tract infections, and yeast and bacterial infections. It is imperative that you understand how to operate and care for this expensive piece of equipment.

Let’s review some of the parts. Arm or Limb (used for carrying)

Cord hanger

Coarse focus (lets you bring specimen into rough view)

Fine focus (lets you bring specimen into clear view)

On/Off Switch (turns on light, controls brightness)

Ocular Lens (Eyepiece) In this case Binocular (2)

Objectives (there are four)

Aperture (hole in stage that allows light through)

Stage (specimen slide is placed here)

Light source Base

A Few More Parts Turret or revolving nosepiece (lets you rotate to whichever objective you want)

Diaphragm Iris diaphragm lever (increases or decreases the aperture to alter light)

Condenser adjustment knob (moves diaphragm up and down to adjust light)

And a Few More Stage clips (to hold the slide in place)

Stage adjustment (to move the stage left/right, forward/backward)

Powers Low or 4x = 40x magnification Medium or 10x = 100x magnification High or 40x = 400x magnification Oil-Immersion or 100x = 1000x magnification

Objectives

Adjust the oculars to fit your eyes Use both hands to adjust

Some microscope accessories. Glass slide covers. These cover the specimen on your slide. Glass slides. The specimen to be analyzed is placed on these. Immersion oil, used with the oil immersion lens. Lens paper is used to clean the eyepiece and objectives. It can be used alone or with a cleaning solution made for microscopes.

Getting started. Glove up!

Switch on the light. Rotate the nosepiece to the lowest power.

Prepare your specimen on a slide, cover it with a glass cover. Place it on the stage and hold it in place with the stage clips.

Use the coarse focus to bring the stage and objective lens closer together, but without touching the slide.

You can use the stage adjustments to scan the slide (right to left, top to bottom) so the specimen is directly under your objective lens.

Once your specimen is in view, STOP. Now use the fine focus to adjust the specimen so it is in clear focus.

Once your specimen is in focus, you can adjust the diaphragm to find the best lighting. lighting

This knob

Moves the diaphragm

Next, you can rotate the nosepiece to the medium power. You should probably only have to use the fine focus at this point to bring your specimen into clear view. You may also adjust the light again.

Repeat this process with the highest power.

If you need to use the oil-immersion lens, place 1 to 2 drops of oil on top of your cover slide. This is the small glass that covers your specimen.

Rotate the 100x objective lens into position.

Slowly move the stage up until the lens makes contact with the oil. Yes, it will actually touch the oil. Refocus with the coarse and fine focus. You will be able to see additional detail with this lens. When finished, clean the lens with lens paper and cleaning solution.

Let’s test what you have just learned. Starting with 1, try to recall the name for the part indicated. Click the mouse to reveal the correct answer. Work your way around to 9. _________1 Arm

5____________ Oculars 6______________ Turret/Nosepiece Objectives 7__________

Coarse/Fine Focus _____________2 Stage 8___________ On/Off Switch ____________3 ________4 Base

Light Source 9____________

A few more to try

Aperture diaphragm adjustment ___________10

Stage adjustment 13___________

Diaphragm __________11

Stage Clip __________12

Aperture 14____________

Putting the microscope away.

Turn off the light. Clean the microscope and surrounding work area.

Next Make sure the stage is centered on the microscope before storing it. You don’t want any overhang that can be damaged when transporting. Rotate the nosepiece so the lowest objective is in place. Use the coarse adjustment to move the stage into the lowest position.

Wind the cord and secure it, so it does not drag on the ground.

Always carry the microscope with one hand on the arm and one under the base.

Always cover the microscope when it is not in use. This will protect it from dust and debris.

Thank you.

Produced by

Yakima Valley Community College Allied Health Technology Programs Summer 2007