What Are Parts Of Microscope And Their Function?

A microscope is used to magnify small objects. Microscopes are often used in scientific or educational settings to observe objects and living organisms that wouldn’t be visible to the naked eye. It is important to learn about the different parts of a microscope to understand how these devices work to get the maximum out of this essential scientific instrument.

Can you name all the different parts of a microscope? Knowing how to properly label microscope parts is important and Here is everything you need to know about the parts of a microscope and their function.   

Parts of Microscope and their Function

Why You Need To Know About Microscope Parts?

Learning about microscope parts provides you with a frame of reference. You can use the correct terms to communicate with other scientists or students.

This is crucial when giving instructions. If you are an instructor, you should take the time to teach students about the different parts of a microscope so you can give detailed instructions on how to prepare a microscope and use it safely.

Knowing the correct terms for the different parts of a microscope will also help you troubleshoot problems. You will be able to look up information on a specific part you are encountering issues with and figure out how to rectify the issue.

For Example, if you want to find the total magnification of the field on which you are looking right now so need to know the magnification of the objective lens and eyepiece. However, before that, you need to spot which one is the objective lens and which one is the eyepiece.

16  Common Parts of Microscope

If you’re new to microscopes and are not familiar with the parts of the microscope it can be quite intimidating to get started. Once you have an understanding of the parts of the microscope it will be much easier to navigate around and begin observing your specimen, which is the fun part!

For Batter Understanding, we divide these parts into two different categories based on their faction.

1) Structural Parts

  1. Head (Body)
  2. Arm
  3. Base

2) Optical Parts

  1. Eyepiece
  2. Eyepiece tube
  3. Objective lenses
  4. Revolving Nosepiece (Turret)
  5. Rack stop
  6. Coarse adjustment knobs
  7. Fine adjustment knobs
  8. Stage
  9. Stage clips
  10. Aperture
  11. Illuminator
  12. Condenser
  13. Diaphragm
Microscope parts lablled diagram

1) Structural Parts

The three basic, structural components of a compound microscope are the head, base, and arm.

  • Head/Body houses the optical parts in the upper part of the microscope
  • Base of the microscope supports the microscope and houses the illuminator
  • Arm connects to the base and supports the microscope head. It is also used to carry the microscope. Some high-quality microscopes have an articulated arm with more than one joint allowing more movement of the microscopic head for better viewing.

When carrying a compound microscope always take care to lift it by both the arm and base, simultaneously.

2) Optical Parts

The microscope optical train typically consists of an illuminator (including the light source and collector lens), a substage condenser, specimen, objective, eyepiece. The optical parts of the microscope are used to view, magnify, and produce an image from a specimen placed on a slide. These parts include:

1) Eyepiece:

An eyepiece, or ocular lens, is a type of lens that is attached to a variety of optical devices such as telescopes and microscopes. It is so named because it is usually the lens that is closest to the eye when someone looks through the device.  Put simply, this is where you put your eye to see the image.

The eyepiece magnifies the primary image produced by the objective; the eye can then use the full resolution capability of the objective so that it can be seen by the human eye.

2) Eyepiece tube:

Eyepiece Tube holds the eyepieces in place above the objective lens. It is the bridge between the eyepiece and the objective lens.  Binocular microscope heads typically incorporate a diopter adjustment ring that allows for the possible inconsistencies of our eyesight in one or both eyes.

3) Objective lenses:

The objective lens of a microscope is the one at the bottom near the sample. These are the major lenses used for specimen visualization. They have a magnification power of 40x-100X.

At its simplest, it is a very high-powered magnifying glass, with a very short focal length. This is brought very close to the specimen being examined so that the light from the specimen comes to a focus inside the microscope tube.

4) Revolving Nosepiece or Turret:

The microscope nosepiece, also known as the revolving turret, sits below the head of the microscope and locks the objective lens into position over the stage aperture by rotating in either direction.

Revolving Nosepiece is the part of the microscope that holds two or more objective lenses and can be rotated to easily change power (magnification). Objective Lenses: Usually you will find 3 or 4 objective lenses on a microscope. They almost always consist of 4x, 10x, 40x and 100x powers.

5) Rack stop:

The rack stop is a small screw that is mounted next to the stage. You shouldn’t have to adjust the rack stop of your microscope. The default setting will prevent you from getting the stage too close to the objective lenses.

This is an adjustment that determines how close the objective lens can get to the slide. It is set at the factory and keeps students from cranking the high-power objective lens down into the slide and breaking things.

6) Coarse adjustment knobs:

The coarse adjustment knob located on the arm of the microscope moves the stage up and down to bring the specimen into focus. The gearing mechanism of the adjustment produces a large vertical movement of the stage with only a partial revolution of the knob.

The coarse adjustment knob should only be used with the lowest power objective lens. Once it is in focus, you will only need to use the fine focus. Using the coarse focus with higher lenses may result in crashing the lens into the slide.

7) Fine adjustment knobs:

Fine adjustment knobs in contrast to the coarse adjustment knobs are going to move the stage much slower and give you much more control over the movement up or down of the stage.

Fine adjustment knobs are used for focusing finer details of a specimen being viewed. Objectives like low power and high power objectives are used with a fine Adjustment knob for a clearer image in higher resolution.

8) Stage:

All microscopes are designed to include a stage where the specimen (usually mounted onto a glass slide) is placed for observation. Stages are often equipped with a mechanical device that holds the specimen slide in place and can smoothly translate the slide back and forth as well as from side to side.

9) Stage Clips:

Stage clips hold the slide in place. If you have the true stage clips, they work just like clips. They are forced down by a spring and you just lift the clip and put the slide underneath. The clip will keep the slide in place.

If you have a mechanical stage, the clips act more like a vice where you adjust the clips to clamp the slide in place. You can then turn the knobs of the mechanical stage to move the slide to the desired position.

10) Aperture:

The aperture is the hole in the center of the microscope stage where light makes its way to the stage. Numerical aperture is related but it is more of a concept related to the angle of the cone of light that shines through the stage than a component part of the microscope.

11) Illuminator:

Illuminator built into the base of most microscopes. The purpose of the illuminator is to provide even, high-intensity light at the place of the field aperture so that light can travel through the condenser to the specimen.

The illuminator as you can probably derive from the name is the light source of the microscope. Most microscopes have a built-in 110 volt steady light source that shines up through the microscope stage aperture.

Although most microscopes have a built-in illuminator that generates the light, there are some old-school microscopes that have a mirror as an illuminator and reflect light coming from an external light source up through the microscope stage to illuminate the specimen.

12) Condenser:

A condenser is used to collect and focus the light from the illuminator onto the specimen. It is located under the stage often in conjunction with an iris diaphragm. Iris Diaphragm controls the amount of light reaching the specimen. It is located above the condenser and below the stage.

It serves to gather wavefronts from the microscope light source and concentrate them into a cone of light that illuminates the specimen with uniform intensity over the entire view field.

13) Iris Diaphragm:

Iris Diaphragm controls the amount of light reaching the specimen. It is located above the condenser and below the stage. Most high-quality microscopes include an Abbe condenser with an iris diaphragm. Combined, they control both the focus and quantity of light applied to the specimen.

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