MICROPARA LABORATORY: Parts of Microscope

Eyepiece Lens

The top lens that you look through.

Eyepiece Lens

Usually 10X or 15X power.

Tube

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.

Illuminator

A steady light source used in place of a mirror.

Illuminator

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

Flat platform where slides are placed.

Stage

Stage clips hold slides in place.

Stage

Mechanical stage allows movement of the slide left-right or up-down by turning two knobs.

Revolving Nosepiece (Turret)

Holds two or more objective lenses and can be rotated to easily change power.

Rack Stop

Prevents the objective lens from getting too close to the slide.

Rack Stop

Factory set to avoid breaking the slide.

Rack Stop

Can be adjusted for thin slides if focusing is difficult at high power.

Rack Stop

This is an adjustment that determines how close the objective lens can get to the slide.

Rack Stop

It is set at the factory and keeps students from cranking the high power objective lens down into the slide and breaking things.

Rack Stop

You would only need to adjust this if you were using very thin slides and you weren't able to focus on the specimen at high power.

Condenser Lens

Focuses light onto the specimen.

Condenser Lens

Most useful at high powers (400X and above).

Condenser Lens

Microscopes with in-stage condenser lenses provide sharper images than those without.

Diaphragm (Iris Arm)

Rotating disk under the stage with different-sized holes.

Diaphragm (Iris Arm)

Controls intensity & size of light cone projected onto the slide.

Diaphragm (Iris Arm)

No fixed setting—adjust based on:

Diaphragm (Iris Arm)

Transparency of the specimen

Diaphragm (Iris Arm)

Degree of contrast needed

Diaphragm (Iris Arm)

Objective lens in use