Parts of a Microscope and Their Functions

The microscope is a scientific instrument that has a long and fascinating history. It is a device that uses lenses to magnify objects, allowing us to see them in greater detail.

The earliest known microscope was developed in the late 16th century by Dutch scientist Antonie van Leeuwenhoek. He used a single lens to create a simple microscope that was able to magnify objects up to about 200 times their actual size. Van Leeuwenhoek’s microscope was used to study a variety of small objects, including tiny organisms such as bacteria and protozoa.

In the 17th and 18th centuries, several other scientists and inventors developed more advanced microscopes that used compound lenses to achieve even greater magnifications. These microscopes were used to study a wide range of objects, including plants, minerals, and insects.

In the 19th and 20th centuries, the development of the electron microscope revolutionized the field of microscopy. These microscopes use a beam of electrons instead of light to produce an image of an object, allowing for even higher magnifications and greater resolution. Today, microscopes are used in a wide range of scientific and medical fields, including biology, medicine, and materials science.

What are Microscopes? – Definition of Microscope

• A microscope is a laboratory optical instrument, which is used to examine or study or see objects that are too small to be seen by the naked eye.
• There are present different types of microscopes, such as; light microscopes, Electron microscopes, Scanning probe microscopes, Fluorescence microscopes, Super-resolution microscopes, and  X-ray microscopes.
• Microscopes are creat an image of the sample or specimen and then send it as a beam of light or electrons to its optical path, or by scanning across, and a short distance from the surface of a sample using a probe. 
• In the laboratory, Microscopes are used to visualize minute objects, for example; plant cell, animal cell, bacteria, fungi, etc.
• All microscopes of high grade have achromatic, parcentered, parfocal lenses.
• Microscopes consist of different types and numbers of magnifying lenses.
• A Microscopes are made up of two parts, the holding part which supports the microscopes and its components, and the optical part which is used for magnification and viewing of the specimen images.
• They contain 2 systems of lenses, one is eyepiece and the other is one or more objective lenses.

Type of Microscopes

There are present mainly 3 types of Microscopes. They are classified based on their working principle and uses.

1. Optical Microscopes: Optical Microscope Also Known as Light Microscope. There are present two types of optical Microscope such as;
   • Simple microscope
   • Compound microscope (Contain two sets of lenses)
2. Electron microscopes: There are two main types of electron microscope;
   • The Transmission Electron Microscope (TEM)
   • The Scanning Electron Microscope (SEM)
3. Scanning probe microscopes

Except for these three types, there are also present other types of microscopes such as X-ray microscopes, ultrasonic microscopes, etc.

*Modern microscopes are equipped with digital cameras, which can take pictures of the specimens. These pictures are then displayed on a monitor.

General Working Principle of Microscopes

In a microscope, light rays first passed through the specimen and then is transmitted through two sets of lenses, the objective, which is nearest to the specimen, and the eyepiece, which is further away from the specimen.  

The magnified image of the specimen is first produced by the objective. This is known as the primary image. The eyepiece then magnifies the primary image into the final one that is seen by the observer.  The total magnification obtainable by the microscopes is the product of the magnification of the objective and that of the eyepiece.  Examples are given below:

Objective magnification	Eyepiece magnification	Total magnification
10X	10X	100X
40X	10X	400X
100X	10X	1000X

Applications of Microscopes

Microscopes are used in a wide range of scientific and medical fields, including biology, medicine, materials science, and nanotechnology. Here are a few examples of how microscopes are used in these fields:

1. Biology: Microscopes are essential tools in biology and are used to study cells, tissues, and microorganisms. They are also used to study the internal structure of plants and animals, and to examine tissues and cells for signs of disease or damage.
   • To study protein interaction or protein conformation.
   • To Study the membrane dynamics.
   • To study the concentration of calcium ion and pH changes.
   • To Determine the shape of cells and intercellular structure.
   • To determine the localization of specific proteins.
   • To Study the Dynamics of protein.
   • To study the iron concentration.
   • Microscopes also used in forensic laboratories.
   • Used in counting of blood cells.
2. Medicine: Microscopes are used in medicine to examine tissues and cells for diagnostic purposes. They are also used in research to study the causes and effects of diseases, and to develop new treatments.
3. Materials science: Microscopes are used in materials science to study the structure and properties of materials at the micro and nanoscale. This includes the study of metals, ceramics, polymers, and other materials.
4. Nanotechnology: Microscopes are essential tools in the field of nanotechnology, which involves the study and manipulation of materials at the atomic and molecular level. Scanning probe microscopes and electron microscopes are commonly used to study the properties of nanomaterials.

Overall, microscopes play a vital role in many scientific and medical fields, allowing us to study and understand the world around us at a level of detail that would be otherwise impossible.

The microscope parts are divided into two main categories,  such as;

1. Structural parts of microscope 
2. Optical parts of microscope 

Structural parts of a microscope	Microscope Part’s Function
Head	The head portion or body tube of microscope connects the eyepiece to the objective lenses.
Arm	The arm Supports the head or body tube and connects it to the base of the microscopes.
Base	The bottom portion of Microscopes on which the arm portion is standing. It holds all the essential components.

Structural parts of a microscope and their functions

The structural parts of microscope provide supports and connecting all the components of microscope. There are present three important structural parts of microscope such as;

1. Head

• It is located at the upper portion of microscope. The head portion of microscope is also known as the Body tube.

Function of Head

• The head portion or body tube of microscope connects the eyepiece to the objective lenses.

2. Arm

• In a microscope, the arm is the part of the microscope that connects the eyepiece tube to the base. It is typically made of metal or plastic and is used to support the weight of the microscope.
• The arm is an important part of a microscope and is used to provide stability and support to the microscope. It is usually designed to be strong and durable, able to withstand the weight of the microscope and the forces exerted on it during use.
• The arm is typically located on the side of the microscope and is used to support the weight of the eyepiece tube, objective lens, and stage. It is usually adjustable, allowing the user to change the position of the eyepiece tube and the stage as needed.
• Overall, the arm is an essential part of a microscope and is used to provide stability and support to the microscope.
• It refers to the holding portion of a microscope, which is used to carry the microscopes.
• Few high-quality microscopes contain an articulated arm with more than one joint allowing more movement of the microscopic head for better viewing.

Function of Arm

• The arm Supports the head or body tube and connects it to the base of the microscopes.

3. Base

• In a microscope, the base is the bottom part of the microscope that provides support and stability to the entire instrument. It is typically made of metal or plastic and is used to hold the microscope in place while it is being used.
• The base is an important part of a microscope and is used to provide a stable foundation for the microscope. It is typically designed to be heavy and sturdy, able to withstand the weight of the microscope and the forces exerted on it during use.
• The base is usually equipped with a series of adjustment knobs, such as the coarse focus knob and the fine focus knob, which are used to fine-tune the focus of the image. It is also equipped with a stage, which is a platform on which the specimen is placed for viewing, and a light source, which is used to illuminate the specimen.
• Overall, the base is an essential part of a microscope and is used to provide support and stability to the entire instrument.

Function of Base

• The Base portion provides support to the microscope.

Optical parts of a microscope and their functions

Optical parts of a microscope	Function
Eyepiece	Help the viewer to see the magnified specimen. Helps to magnify the image of specimens. It corrects the defects of the objective.
Eyepiece tube	connects the eyepiece and ocular lens to the objective lenses
Nosepiece	It holds 2 -3 objective lense.
Microscope Objective lenses	Helps to increase the magnification levels of specimen image. Together the light rays coming from any point of the objects. To unite the light at a point of the image.
The Adjustment knobs	A coarse adjustment knob is used to focus the microscope. It is always used first, and it is used only with the low power objective. The fine adjustment knob is used to focus the microscope. It is used with the high­ power objective to bring the specimen into better focus
Stage	The test specimen is placed over it for viewing.
Stage clips	It holds the specimen slides in place.
Aperture	Through Aperture the base (transmitted) light reaches the stage.
Microscopic illuminator	light sources for Microscope.
Condenser	The condenser helps to collect and focus the light from the illuminator on to the specimen.
Diaphragm	Diaphragm is used to vary the intensity and size of the cone of light that is projected upward into the slide.

The optical part of the Microscope plays an important role to magnify the object. It consists of the following components;

1. Eyepiece

In a microscope, the eyepiece is a lens that is used to magnify the image produced by the objective lens. It is located above the stage and is used to view the specimen through the microscope.

The eyepiece is typically equipped with a focusing mechanism that allows the user to fine-tune the focus of the image. It is also equipped with a diopter adjustment, which allows the user to adjust the eyepiece to their eyesight.

There are several different types of eyepieces that are used in microscopes, including wide-field eyepieces and high-power eyepieces. Wide-field eyepieces have a wider field of view and are well-suited for viewing larger specimens or for scanning a wide area. High-power eyepieces have a higher magnification and are better suited for viewing smaller specimens or for studying fine details.

Overall, the eyepiece is an important part of a microscope and is used to magnify the image produced by the objective lens, allowing the user to view the specimen in detail.

• Eyepiece consists of two lenses, the ocular(The first one, near the eye) and eyepiece (The last one, away from the eye).
• This part of microscope is also known as ocular.
• Eyepiece is located at the top of the microscope.
• The magnifying power of an ocular lens varies from 5x to 30x, but normally 10X or 15X magnifying power is used.
• To get the total magnification level, multiply the magnification of the objective used (ex: 10X eyepiece * 40X objective = 400X total magnification).

Types of Eyepiece:

Several types of ocular are employed depending upon the kind of objective located on the microscope those most commonly used are;

1. Huygenian: In this type of eyepiece to simple Plano-convex lenses are employed the convex surfaces of both lenses face downward oculars in this group are spoken as negative eyepiece
2. Hyperplane: Oculars of this type are referred to as hyperplane Planoscopic, periplane, etc. They may be employed with the high power achromatic, Fluorite, and apochromatic objectives without introducing chromatic aberrations in the image.
3. Compensating: Ocular of this type consists of achromatic triplet combination of lens. These eye-piece are more perfectly corrected than are those of huygenion and hyperplane types.

Functions of Eyepiece

• Help the viewer to see the magnified specimen.
• Helps to magnify the image of specimens.
• It corrects the defects of the objective.

2. Eyepiece tube

• In a microscope, the eyepiece tube is the part of the microscope that holds the eyepieces. It is located above the stage and is used to magnify the image produced by the objective lens.
• The eyepiece tube is typically equipped with one or two eyepieces, which are lenses that magnify the image produced by the objective lens. The eyepieces are adjustable, allowing the user to fine-tune the focus of the image and to adjust the eyepiece to their eyesight.
• The eyepiece tube is an important part of a microscope and is used to magnify the image produced by the objective lens. It is typically made of metal or plastic and is designed to be easy to use and to hold the eyepieces securely in place.
• Overall, the eyepiece tube is an essential part of a microscope and is used to magnify the image produced by the objective lens.

Functions of Eyepiece tube

• connects the eyepiece and ocular lens to the objective lenses 

3. Nosepiece

• In a microscope, the nosepiece is a rotating turret that holds the objective lenses. It is located above the stage and is used to select the objective lens that will be used to view the specimen.
• The nosepiece typically has several objective lenses of different magnifications, which can be rotated into place as needed. The user selects the desired objective lens by rotating the nosepiece until the desired lens is aligned with the eyepieces.
• The nosepiece is an important part of a microscope and is used to switch between different objective lenses as needed. It is typically made of metal or plastic and is designed to be easy to rotate and to hold the objective lenses securely in place.
• Overall, the nosepiece is an essential part of a microscope and is used to select the objective lens that will be used to view the specimen.
• It is also known as a revolving turret.

Functions of Nosepiece

• It holds 2 -3  objective lense.

4. Microscope Objective lenses

• Objective lenses are located below the Nosepiece.
• Usually, you can find 3 or 4 objective lenses on a microscope.
• Commonly there are present 4 types of objective lenses with different magnification power such as 4X, 10X, 40X, and 100X. 
• If we use a 4x Objective lens with a 10x eyepiece (most common), then the total magnification power will be 40x(4×10), In similarly way  the total magnification power of other lenses will be 100x(10×10), 400x(40×10), and 1000x(100×10).
• There are three kinds of objective lenses 4X (scanning objective) 10X (Low power objective lens). 40X (High power objective lens). 100X (Oil immersion objective lens).
• When the microscope is put away after use, the scanning objective or the 4x objective should be locked into place in the rotating nose piece. The stage should be in the middle, and the objectives should be rolled up and away from the stage.

Types of Objective lenses:

There are three types of objective lens;

• Achromatic: The achroma are the simplest in construction and the least expensive.  The control of oberrations becomes more difficult when the power is increased.
• Fluorite: This is also called semi apochromatic aberrations are largely eliminated by the use of flurite objectives.
• Apochromatic: This is the costly objective lens with respect to other lenses and it has the power to correct aggeration highly perfect.

Functions of Objective lenses

• Helps to increase the magnification levels of specimen image.
• Together the light rays coming from any point of the objects.
•  To unite the light at a point of the image.

5. The Adjustment knobs

• In a microscope, the adjustment knobs are used to fine-tune the focus of the image and to position the specimen in the focal plane of the objective lens. There are typically two adjustment knobs on a microscope: the coarse focus knob and the fine focus knob.
• The coarse focus knob is used to make large, rough adjustments to the focus of the image. It is typically located on the side of the microscope and is used to move the objective lens up and down.
• The fine focus knob is used to make smaller, more precise adjustments to the focus of the image. It is usually located on the top of the microscope and is used in conjunction with the coarse focus knob to achieve a clear and sharply focused image.
• Overall, the adjustment knobs are an important part of a microscope and are used to fine-tune the focus of the image and to position the specimen in the focal plane of the objective lens.

Functions of Adjustment knobs

• The first dial used to bring a specimen into focus is the Coarse focus knob.
• The second dial used to bring a specimen into focus is the fine focus knob.

Note: The fine adjustment knob is utilised for all focusing when using high-power lenses and to bring the specimen into sharp focus when using low power.

What is Working Distance? The working distance of an objective is the distance between the front surface of the lens and the cover glass or specimen surface when both are in sharp focus.

6. Stage

• In a microscope, the stage is a platform on which the specimen is placed for viewing. It is typically located below the objective lens and is used to support the specimen and hold it in place while it is being viewed.
• The stage is an important part of a microscope and is used to position the specimen in the focal plane of the objective lens. It is typically adjustable, allowing the user to move the specimen horizontally and vertically to align it with the objective lens.
• The stage is typically made of metal or glass and is often coated with a smooth, non-reflective surface to reduce glare and improve the contrast of the image. It is usually equipped with stage clips, which are used to hold the specimen in place, and a stage aperture, which is an adjustable opening that controls the amount of light that passes through the specimen.
• Overall, the stage is an essential part of a microscope and is used to position and hold the specimen in place while it is being viewed.
• Most of the microscope contains a mechanical stage, which has two knobs to control the slide.
• One knob moves the slide left and right, the other moves it forward and backward.

Functions of Stage

• The test specimen is placed over it for viewing.

7. Stage clips

• In a microscope, the stage clips are small clips that are used to hold the specimen in place on the stage. They are typically located on the sides or corners of the stage and are used to secure the specimen while it is being viewed.
• Stage clips are typically made of metal or plastic and are adjustable, allowing them to hold specimens of different sizes and shapes. They are an essential part of a microscope and are used to keep the specimen stationary, which is important for achieving a clear and focused image.
• There are several different types of stage clips, including spring-loaded clips, thumbscrew clips, and lever-controlled clips. Each type has its own unique design and is best suited for specific applications.
• Overall, stage clips are a useful and important part of a microscope, allowing the user to securely hold the specimen in place while it is being viewed.

Types of Stage clips used in Microscope

There are several different types of stage clips that are used in microscopes, each with its own unique design and best suited for specific applications. Here are a few common types of stage clips:

1. Spring-loaded clips: These clips are designed to hold the specimen in place using a spring-loaded mechanism. They are easy to use and can hold a variety of different sizes and shapes of specimens.
2. Thumbscrew clips: These clips are tightened or loosened using a thumbscrew, allowing them to hold the specimen in place with a secure grip. They are often used for larger or heavier specimens.
3. Lever-controlled clips: These clips are adjusted using a lever, which allows the user to easily hold the specimen in place with a secure grip. They are often used for smaller or more delicate specimens.
4. Magnetic clips: These clips use a magnet to hold the specimen in place. They are often used for thin or transparent specimens and are less likely to damage the specimen than other types of clips.

Overall, the type of stage clip used in a microscope depends on the size and type of specimen being viewed, as well as the specific requirements of the application.

Functions of Stage clips

• It holds the specimen slides in place. 

8. Aperture

• It is a hole in stage, which is located below the objective lense.
• In a microscope, the aperture is an adjustable opening that controls the amount of light that passes through the condenser and illuminates the specimen being viewed. It is typically located below the stage, between the light source and the condenser, and consists of a series of overlapping metal or glass blades that can be adjusted to allow more or less light to pass through.
• The aperture is controlled by a lever or knob on the microscope, and can be adjusted to control the brightness and contrast of the image being viewed. It is an important part of a microscope and is used in conjunction with the diaphragm (also known as the iris) to control the illumination of the specimen.
• In addition to controlling the amount of light entering the microscope, the aperture can also be used to focus the light on the specimen. This is especially useful for specimens that are thin or transparent, as it can help to improve the contrast and resolution of the image.
• Overall, the aperture is an important part of a microscope and is used to control the illumination of the specimen, as well as to improve the contrast and resolution of the image.

Functions of Stage clips

• Through Aperture the base (transmitted) light reaches the stage.

9. Microscopic illuminator or Built-In Light Source

• A microscopic illuminator is a device that provides light to a microscope. It is typically located below the stage and is used to illuminate the specimen being viewed. The light is directed through the specimen and into the objective lens, which magnifies the image and projects it onto the eyepieces or a camera.
• There are several different types of microscopic illuminators, including halogen lamps, LED lamps, and fluorescent lamps. Each type has its own unique characteristics and is best suited for specific applications.
• Halogen lamps are a common type of illuminator that produce a bright, white light. They are relatively inexpensive and have a long lifespan, but they can generate a significant amount of heat.
• LED lamps are a newer type of illuminator that are becoming increasingly popular. They are more energy efficient than halogen lamps and produce less heat, but they may not be as bright.
• Fluorescent lamps are another type of illuminator that are often used in microscopes. They produce a diffuse, even light that is well-suited for viewing thin specimens or for studying fluorescently labeled samples.
• Overall, the type of illuminator used in a microscope depends on the specific application and the requirements of the specimen being viewed.
• Optical Microscopes contain an internal light source or Built-In Light Source known as an illuminator.
• This light source illuminates specimens for viewing under a microscope.
• There are three principal varieties of optical microscopes:
  1. Transmitted light microscope – Illuminates the item with transmitted light.
  2. Reflected light microscope – Illuminates the item using reflected light
  3. Epi-lit microscope – The object is illuminated by epi-illumination.

• When an additional light source is utilized to illuminate the sample, this is known as epi-illumination.
• When using transmitted light, the light is gathered by the objective lens after passing through the object.
• When using reflected light, the light is focused on the objective lens after bouncing off the object’s surface.
• With epi-illuminated microscopy, the light is directed perpendicular to the sample from above.

Functions of Microscopic illuminator or  Built-In Light Source

• Microscopic illuminators or built-in light source function as light sources for Microscope. it captures light from an external source of a low voltage of about 100v.

10. Condenser

• A condenser may be defined as a series of lenses for illuminating with transmitted light an object to be studied on the stage of the microscope.
• Additionally, you’ll need a microscope with an Abbe condenser to get the best clarity at high levels of magnification settings.
• Condenser is located under the stage next to the diaphragm of the microscope.
• They have a high magnification of 400X and above. 
• Condensers with high magnification  power can produce a high quality image.
• For 1000x resolution, a reasonably sophisticated microscope with an Abbe condenser is required. (More sophisticated microscopes include an Abbe condenser with a high magnification of roughly 1000X.)

Types of Condenser:

 condenser used two methods of illumination;

1. Bright field illumination: There are present Three Types of condenser which used in bright field  illumination;
2. Abbe condenser: The Abbe condenser utilizes only two lenses. It is not corrected for spherical and chromatic aberration
3. Achromatic condenser: These condensers are designed to correct for chromatic aberration, which is the distortion of an image due to the refraction of light through different lenses. They are often used in general-purpose microscopes and are well-suited for viewing most types of specimens.
4. Plan achromatic condensers: These condensers are similar to achromatic condensers, but they are designed to provide a wider field of view and are better suited for viewing large or flat specimens.
5. Variable Focus Condensor: The variable focus condenser is a two lenses system in which the upper lens is fixed and the lower element focussable.
6. Plan fluorite condensers: These condensers are made of a special type of glass called fluorite, which has a low dispersion and is highly resistant to chromatic aberration. They are often used in high-resolution microscopes and are well-suited for viewing thin or transparent specimens.
7. Phase contrast condensers: These condensers are used in phase contrast microscopes, which are specialized microscopes that are used to study transparent or unstained specimens. They use a special technique to enhance the contrast of the image and make it easier to see fine details.

Darkfield illumination

There are present Three Types of condenser which are used in dark field illumination;

1. Abbe Condenser: It may be employed either by inserting a dark field stop below the condenser or by unscrewing the top part of condenser
2. Paraboloid Condenser: The paraboloid condenser is designed to be used with high power oil immersion objectives and an intense source of light
3. Cardioid Condenser: The cardioid condenser is specially designed to be used for the examination of colloidal solution or suspension.

Functions of Condenser

• Condenser helps to collect and focus the light from the illuminator on to the specimen.

11. Diaphragm

• Diaphragm also known as iris.
• High quality microscopes contain an Abbe condenser with an iris diaphragm. Combined, they control both the focus and quantity of light applied to the specimen.
• In a microscope, the diaphragm (also known as the iris) is a mechanism that controls the amount of light that enters the objective lens and illuminates the specimen being viewed. It consists of a series of overlapping metal or glass blades that can be adjusted to allow more or less light to pass through.
• The diaphragm is usually located below the stage, between the light source and the objective lens. It is controlled by a lever or knob on the microscope, and can be adjusted to control the brightness and contrast of the image being viewed.
• In addition to controlling the amount of light entering the microscope, the diaphragm can also be used to focus the light on the specimen. This is especially useful for specimens that are thin or transparent, as it can help to improve the contrast and resolution of the image.
• Overall, the diaphragm is an important part of a microscope and is used to control the illumination of the specimen, as well as to improve the contrast and resolution of the image.
• Iris is utilised to expand or contract the condenser aperture. Iris is approximately two-thirds closed for 10X objective, slightly open for 40X objective, and totally open for 100X target. The lamp brightness control, not the iris, should be used to lessen the intensity of the illumination. If the condenser aperture is too narrow, there will be a loss of image detail (resolution).

Functions of Diaphragm

• Diaphragm is used to vary the intensity and size of the cone of light that is projected upward into the slide. 

12. Condenser focus knob

• In a microscope, the condenser focus knob is a mechanism that adjusts the focus of the light from the illuminator onto the specimen being viewed. The condenser is a lens system located below the stage that focuses the light onto the specimen. The focus knob is used to adjust the position of the condenser lens, which in turn adjusts the focus of the light.
• The condenser focus knob is typically located on the side of the microscope, near the base. It is used in conjunction with the fine focus knob, which adjusts the focus of the objective lens, to achieve a clear and sharply focused image of the specimen.
• The condenser focus knob is an important part of a microscope and is used to fine-tune the focus of the light onto the specimen. It is especially important when viewing thin or transparent specimens, as it can help to improve the contrast and resolution of the image.

Functions of Condenser focus knob

• It moves the condenser up or down thus controlling the focus of light on the specimen.

13. The rack stop

• It is located over the stage.
• The rack stop is a mechanism on a microscope that limits the range of motion of the focus knob. It is a small metal pin or stop that is located on the base of the microscope, near the focus knob.
• The rack stop is used to prevent the objective lens from moving too far down and coming into contact with the specimen. If the objective lens comes into contact with the specimen, it can damage the specimen or the lens itself. The rack stop prevents this by limiting the range of motion of the focus knob.
• To use the rack stop, the user simply sets the focus knob to the desired position and then pushes the rack stop into place. This locks the focus knob in place and prevents it from being moved too far down. The rack stop can be released by pressing a button or lever, allowing the focus knob to be adjusted again.
• Overall, the rack stop is a useful feature on a microscope that helps to protect the specimen and the objective lens from damage. It is particularly useful when working with delicate specimens or when making fine focus adjustments.

Functions of The rack stop

• It regulates the distance between the stages. This prevents the objective lens from being too close to the specimen slide, which could cause damage. It prevents the specimen slide’s height from hitting the objective lens.

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Abbe Condenser

• It is a type of Condenser with high resolution, approximately 400x or above.
• Abbe condenser is only found in high-quality microscopes.
• These types of condensers can produce a sharp or clear image with high resolution.

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The parts of the microscope and their roles are summarised in the table below.

Part of microscope	Function
Objective lens	Magnifies the image of the specimen
Eyepiece	Magnifies the image produced by the objective lens
Eyepiece tube	Holds the eyepiece and allows it to be adjusted
Arm	Connects the eyepiece tube to the base and supports the weight of the microscope
Base	Provides support and stability to the entire microscope
Stage	Platform on which the specimen is placed for viewing
Stage clips	Hold the specimen in place on the stage
Light source	Illuminates the specimen
Condenser	Focuses the light onto the specimen
Aperture	Controls the amount of light that passes through the specimen
Diaphragm	Controls the amount of light that enters the objective lens
Coarse focus knob	Makes large, rough adjustments to the focus of the image
Fine focus knob	Makes smaller, more precise adjustments to the focus of the image
Rack stop	Limits the range of motion of the focus knob to prevent the objective lens from coming into contact with the specimen
Nosepiece	Holds the objective lenses and allows them to be rotated into place

Parts of a Electron Microscope

An electron microscope is a type of microscope that uses a beam of electrons to produce high-resolution images of samples. Here are some of the main parts of an electron microscope:

1. Electron gun: This is the source of the electron beam that is used to illuminate the specimen. It typically consists of a cathode, which emits electrons, and an anode, which accelerates the electrons to a high energy level.
2. Objective lens: This lens system focuses the electron beam onto the specimen and magnifies the image. It is usually made of a series of electromagnetic lenses that are capable of focusing the electrons to a very small spot size.
3. Specimen stage: This is the platform on which the specimen is placed for viewing. It is typically equipped with a range of mechanical and electrical controls that allow the specimen to be moved and positioned as needed.
4. Condenser lenses: These lenses focus the electron beam onto the specimen and are used to control the size and intensity of the beam.
5. Column: This is the main part of the electron microscope and houses the electron gun, objective lens, and other components. It is typically made of metal and is designed to be vacuum-sealed to prevent contamination of the sample.
6. Detector: This device is used to detect the electrons that are scattered by the specimen and to produce an image of the sample. There are several different types of detectors that are used in electron microscopes, including scintillators, CCD cameras, and photomultiplier tubes.

Overall, these are some of the main parts of an electron microscope. Each of these components plays an important role in producing high-resolution images of the sample being studied.

Parts of a scanning Electron Microscope

A scanning electron microscope (SEM) is a type of electron microscope that produces high-resolution images of samples by scanning a beam of electrons across the surface of the specimen. Here are some of the main parts of a scanning electron microscope:

1. Electron gun: This is the source of the electron beam that is used to illuminate the specimen. It typically consists of a cathode, which emits electrons, and an anode, which accelerates the electrons to a high energy level.
2. Specimen stage: This is the platform on which the specimen is placed for viewing. It is typically equipped with a range of mechanical and electrical controls that allow the specimen to be moved and positioned as needed.
3. Column: This is the main part of the electron microscope and houses the electron gun, objective lens, and other components. It is typically made of metal and is designed to be vacuum-sealed to prevent contamination of the sample.
4. Scanning coils: These electromagnets are used to deflect the electron beam and scan it across the surface of the specimen.
5. Detector: This device is used to detect the electrons that are scattered by the specimen and to produce an image of the sample. There are several different types of detectors that are used in electron microscopes, including scintillators, CCD cameras, and photomultiplier tubes.
6. Image processing system: This is a computer system that is used to analyze the data collected by the detector and to produce a high-resolution image of the specimen.

Overall, these are some of the main parts of a scanning electron microscope. Each of these components plays an important role in producing high-resolution images of the sample being studied.

Microscope Terms

This is a list of the most common terms used in microscopy.

• Abbe Condenser: A lens that is made to fit under the stage and usually moves up and down. The size of the light beam coming into the lens system is controlled by an iris that can be moved. By changing the size of this iris and moving the lens closer to or farther from the stage, you can change the size and centre of the cone of light that goes through the specimen. Abbe condensers are useful when the magnification is higher than 400X and the numerical aperture of the condenser lens is the same as or greater than the numerical aperture of the objective lens.
• Achromatic Lens: A lens that helps fix the way light gets messed up when it goes through a prism or another lens. Since different colours of light bend at different angles, an achromatic lens is made of different types of glass with different indices of refraction. So, the colours are better aligned, but not as well as they would be with a plan or semi-plan objective lens. Most microscopes have achromatic lenses, but plan or semi-plan lenses are used for more precise tasks.
• Arm: The part of a microscope that connects the eyepiece tube to the base.
• Articulated Arm: An articulated arm is part of a boom microscope stand. It has one or more joints that allow the microscope head to move in more ways, giving you a wider range of viewing options.
• Base: Usually, a microscope has a head or body and a base. The base is what holds everything up.
• Binocular Microscope: A microscope with a head that has two eyepiece lenses is called a binocular microscope. Binocular is usually used to describe high-power or compound microscopes with two eyepieces that look through a single objective lens. A stereo or low power microscope may also have two eyepieces, but since each eyepiece looks through a different objective lens, the specimen appears in stereo (3-Dimensional). So that we can tell them apart from monocular and trinocular microscopes, we put both kinds of binocular microscopes in the same category.
• Body: The upper part of a microscope, which includes the eyepieces and objectives, is called the body. It is also sometimes called the “head.” Most modern microscopes are modular, which means that you can use the same body with different bases and bases with the same body.
• Boom Stand (Universal Boom Stand): A base for a microscope that has an adjustable arm or “boom” and lets the body be positioned in different ways. Used in commercial applications that involve inspection.
• Calibration: Calibration is the math used to figure out how far something really is when using a reticle.
• Camera adapter: An adapter kit that lets a camera connect to a microscope’s trinocular port (23mm or 30mm port diameter). The camera is attached to a step ring (or T-Mount) and then to an adapter for cameras.
• Clamp Base: A clamp that replaces the traditional base at the bottom of a boom microscope and lets the pole be clamped to the side of a work bench or table.
• C-Mount: This is an adapter for attaching a lens to a camera. It has a standard thread. It fits into a port for three eyes. The mechanical standard is a 1 diameter, 32 TPI (threads per inch), male on the lens and female on the camera. The optical standard is that the image reaches the focal plane 17.5mm past the edge of the lens mounting threads.
• Coarse Focus: This is the knob on the side of the microscope that raises and lowers the objective lens. It works with the fine focus setting.
• Coaxial focus: Coaxial focus is a system for focusing where the knobs for coarse and fine focus are both on the same axis. Most of the time, the larger knob on the outside is the coarse focus, and vice versa. On some coaxial systems, the fine adjustment is calibrated, which makes it possible to record different measurements.
• Comparison Microscope: A microscope that lets you look at two different things at the same time. The microscope has two sets of lenses, but only one set of eyepieces. It is often used in forensic science because of this.
• Compound Microscope: This word was once used to describe a microscope with more than one objective lens. Now, most people think of a compound microscope as a high-power microscope with more than one objective lens with different magnifications that can be switched between. See low power stereo.
• Condenser: A condenser is a lens that focuses light on a sample and makes the resolution better. Compound microscopes are the only ones that have parts in or below the stage.
• Contrast Plate: Only found on stereo microscopes, it has a black side and a white side. Based on your specimen, you can use either side.
• Cover Slip: A thin, square piece of glass or plastic that goes over the specimen on a microscope slide. It makes liquid samples flat and helps focus on a single plane.
• Darkfield Microscopy: Darkfield microscopy is a way to make specimens that haven’t been stained stand out more. It works by lighting up the sample with light that won’t be caught by the objective lens and, therefore, won’t be part of the image. This makes the classic look of a dark background (almost black) with bright objects on it.
• Darkfield Plate: A circular iris that sits on the base of the microscope above the light source and reflects the light horizontally to the specimen to create lateral lighting.
• Digital microscope: A microscope that has a digital camera built in and can send images directly to a computer, TV, or printer.
• DIN: which stands for “Deutsches Institut für Normung” or “German Institute for Standardization,” is an international organisation that sets the “standard” for a wide range of technologies. “DIN standard” microscope objective lenses have an attachment thread with a 20mm diameter and are usually interchangeable between manufacturers.
• Dissecting Microscope: A dissecting microscope is a stereo microscope used in the lab. The terms are often used interchangeably.
• Doublet Lens: A doublet lens is one that has two separate lenses “welded” together. Used to improve colour performance in widefield eyepieces.
• Dual–View: Dual-View is a type of monocular microscope with a second viewing port on the side. Teachers use this phrase a lot. It can also be used for things like photography.
• Electron microscope: A type of microscope that creates an image of the target using electrons instead of light. It can magnify or see details much better than a regular light microscope—up to two million times better. This lets it see smaller objects and details.
• Eyepiece: The eyepiece is the lens closest to your eye. It is also called an ocular. When you multiply the magnification of the eyepiece by the magnification of the objective lens, you get the total magnification of a microscope.
• Eyepiece Tube: The tube that holds the lens of the eyepiece.
• Fine Focus: A knob used with the coarse focus to fine-tune the focus of a specimen.
• Field of View: The size of the circle of light that can be seen through a microscope.
• Focus: Focus is the ability to make an image clear, which is usually done by moving the eyepiece tubes or the stage.
• Gem/Jeweler’s Microscope: Jeweler’s A stereo microscope made for looking at gems and jewellery. It usually has an inclined pole, a powerful zoom, a darkfield plate, and strong, variable lighting.
• Head: This is the upper part of the microscope that has the eyepiece tubes and prisms. It is often called the “body.”
• Illumination System: The light source on a light microscope, which is usually placed under the stage unless the microscope is inverted.
• Immersion Oil: Immersion Oil is a special oil that is used with the 100X objective to focus the light and make the image clearer. On the cover slip, a drop of oil is put, and the objective is moved down until it touches the oil. Immersion oil comes in two main types: Type A and Type B. Type B is thicker.
• Interpupillary Distance: The space between the two eyepieces, which can usually be changed to fit each user.
• Inverted Microscope: A type of microscope where the light source is above the stage and the lenses are below it. Used to look at larger things, usually in containers.
• Iris Diaphragm: The diaphragm is found under the stage of high-power microscopes. It is usually a five-holed disc with different sizes for each hole. It is used to change how much light comes through the stage opening and helps adjust the contrast and resolution of a specimen. It helps especially at higher powers.
• Jeweler’s Clip: A special clip that attaches to the stage and is made to hold precious stones and jewellery so they are easier to see.
• Koehler illumination: Koehler illumination is a way to light up a room. It is named after the person who came up with it, August Koehler. It is also called “double diaphragm illumination” because the light is controlled by both a field diaphragm and an aperture iris diaphragm. If the light path is set up right, the field can be evenly lit, the image can be bright without glare, and the specimen will heat up as little as possible.
• Light Microscopes: Light microscopes are any kind of microscope that uses a light source to make an image of the specimen. This includes almost all compound and stereo microscopes.
• Magnification: A microscope’s main purpose is to make something look bigger. The microscope’s total magnification is found by multiplying the magnification power of the eyepiece lens by the magnification power of the objective lens.
• Mechanical Stage:  A flat mechanism that sits on top of the stage and lets the viewer move a specimen small distances. This is hard to do at higher magnifications without a mechanical stage. Most mechanical stages have an X-axis and a Y-axis so that the person watching can see how far the slide has moved.
• Monocular Microscope: A compound microscope with only one eyepiece is called a monocular microscope.
• Nosepiece: The part at the top of a compound microscope that holds the objective lens is called the nosepiece. A rotating nosepiece or turret is another name for it.
• Numerical Aperture: Numerical Aperture (N.A.) is a way to measure the diameter of the opening in relation to the focal length of a lens and, in turn, the ability of a microscope to see details. N.A. is equal to the index of refraction of the medium in which the object is placed multiplied by the sine of the angle made with the axis by the most oblique ray entering the instrument, with the resolving power increasing as the product increases.
• Objective Lens: The lens closest to the object that receives the light rays from the object first and forms the image in the eyepiece’s focal plane.
• Oil Immersion Lens: An objective lens of 100X or more that is made to work with a drop of immersion oil.
• Parcentered: When the objective is changed, the image of the specimen stays in the middle. Most compound microscopes are centred in the middle.
• Parfocal: When using a parfocal microscope, the image of the specimen stays in focus even when you change the objectives. Most compound microscopes are parfocal.
• Phase Contrast: Phase Contrast is a way to improve contrast that Frits Zernike came up with in 1953 and for which he won the Nobel Prize in Physics. The method changes the phase wavelength of the light, which makes the light reflected by the specimen look dark against a light background. It is useful for looking at things like living tissue cells that are clear.
• Plan Lens: The plan lens is the best objective lens. It “flattens” the image of the specimen and makes the image much clearer and sharper.
• Portable Microscope: A microscope that can be used in the field and doesn’t need to be plugged in. Usually has an LED light source that can be charged so that it can be used in the field where there is no 110/220V electricity.
• Pointer: A piece of high-tensile wire that fits in the eyepiece and lets a viewer point to a certain part of a specimen.
• Pole Stand: A pole stand is a stand for a microscope that has a base and a single vertical pole (or post). Most of the time, the body can move up and down and around the pole.
• Rack and Pinion Focusing Mechanism: A metal rack and pinion are used to focus and move mechanical stages in better microscopes.
• Rack Stop: A safety feature that keeps the objective lens from hitting the stage and damaging the specimen or slide by accident.
• Resolution: Resolution is a lens’s ability to pick out small details in the things it is looking at.
• Reticle: A small glass circle with precise measurements etched into it by a laser. This circle is placed in the eyepiece so that real measurements of the specimen can be taken.
• Revolving Nosepiece: A nosepiece with more than one purpose that spins so that the viewer can choose, usually from one of four different purposes.
• Ring Light: An extra light source that can be attached to a microscope and gives off a ring of light to improve the lighting. Ring lights are usually used on boom microscopes. They can be LED, fluorescent, halogen, or fibre optic.
• Semi-Planned Goals: Make an image clearer and sharper than with a chromatic lens by “flattening” the image of the specimen in part.
• Siedentopf Head: A type of head where the distance between the eyes is changed by twisting the eyepieces in a vertical arc, similar to how binoculars work.
• Slide: A flat, rectangular piece of glass that can hold a sample.
• Slip Clutch: A mechanical device on the focusing knob that lets the knob “slip” if the viewer keeps turning it past its range of motion. Keeps the focusing system from getting broken.
• Stage: The platform where slides and other things are put to be looked at.
• Stage Clips: Stage clips are clips that are attached to the stage and hold the slide in place.
• Stand: This is the part of a stereo or low power microscope that connects the body to the base.
• Stereo Microscope: A stereo microscope is a low-power microscope or dissecting microscope with a separate eyepiece and objective lens for each eye. These separate optical channels let the specimen be seen in stereo or three dimensions. Look at the Compound Microscope.
• Sub-Stage: Parts of the microscope below the stage, such as the light system, are called the “sub-stage.”
• T-Mount: T-Mount is a standard adapter that allows 35mm cameras to be attached to microscopes. Often called a step-ring.
• Tension Adjustment: An adjustment made to the focusing mechanism at the factory to make it both easy to focus and tight enough so that the stage doesn’t move while focusing.
• Turret: Turret is a rotating mechanism, like a nosepiece, condenser, etc.
• Widefield Eyepiece: A better eyepiece lens with a larger diameter that lets you see more and makes it easier to use.

Parts of a Microscope and Their Functions ppt

Parts of a Microscope and Their Functions Video

Parts of a Microscope Worksheet

1. parts of a compound microscope Worksheet

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2. Dissecting microscope (Stereo microscope) Worksheet

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3. Inverted Microscope Worksheet

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FAQ

Q. list the parts of a microscope and what they do. or parts of a microscope and what they do

There are several parts of a microscope, and each has a specific function:

1. Base: The base is the lower part of the microscope that supports the rest of the instrument. It often has a built-in light source or a holder for a lamp.
2. Stage: The stage is a platform that holds the sample being viewed. It is typically located just above the base and is adjustable so that the sample can be positioned in the field of view.
3. Objective lenses: The objective lenses are located at the bottom of the microscope and are used to focus the image of the sample. There are typically several objective lenses of different magnifications available, and they can be rotated into place as needed.
4. Revolving nosepiece: The revolving nosepiece is a turntable that holds the objective lenses and allows them to be rotated into position.
5. Eyepiece: The eyepiece is the lens through which the user views the image of the sample. It is located at the top of the microscope and is often adjustable to accommodate users with different visual acuities.
6. Arm: The arm is the long, horizontal part of the microscope that connects the base to the eyepiece.
7. Fine focus knob: The fine focus knob is used to make small adjustments to the focus of the image. It is typically located near the eyepiece and is used in conjunction with the coarse focus knob.
8. Coarse focus knob: The coarse focus knob is used to make larger adjustments to the focus of the image. It is typically located near the base of the microscope and is used in conjunction with the fine focus knob.
9. Illumination system: The illumination system is the source of light that is used to illuminate the sample being viewed. It may be a lamp, LED, or other type of light source.
10. Condenser: The condenser is a lens or system of lenses that is used to focus the light from the illumination system onto the sample. It is typically located below the stage and is adjustable to vary the intensity of the light.
11. Diaphragm: The diaphragm is an adjustable opening that controls the amount of light that is allowed to pass through the condenser and onto the sample. It is used to fine-tune the illumination of the sample.
12. Iris diaphragm: The iris diaphragm is a circular opening that is used to control the amount of light that is allowed to pass through the condenser. It is similar to the diaphragm but is typically used on more advanced microscopes.

Reference

• https://www.amscope.com/microscope-parts-and-functions
• https://sciencing.com/parts-microscope-uses-7431114.html
• https://www.pobschools.org/cms/lib/NY01001456/Centricity/Domain/349/TheMicroscope-howtouse.pdf
• https://www.microscopeworld.com/t-parts.aspx
• https://www.microscope.com/compound-microscope-parts
• https://www.microscopemaster.com/parts-of-a-compound-microscope.html
• https://microscope-microscope.org/microscope-info/microscope-parts/
• https://en.wikipedia.org/wiki/Microscope
• https://www.keyence.com/ss/products/microscope/bz-x/study/principle/structure.jsp