Parts of a Microscope with Functions and Labeled Diagram

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What is Microscope?

• In science labs, microscopes are tools used to view tiny objects, such cells and microbes, by producing a magnified contrasted image. 
• Each lens used for magnifying in a microscope has its own distinct capability of magnifying. The focal strength of the lens will decide how much the specimen is magnified.
• They are able to function because they were built with unique parts that allow them to reach high magnification levels. When animal and plant cells look at minute bacterial cells, for instance, they are able to perceive very small specimens and discern their structural distinctions.  
• Light, dark-field, phase contrast, electron, fluorescence, and other types of microscopes are among the several kinds of microscopes.

Structural parts of a microscope and their functions

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

1. Head: The head is a metal tube that is cylindrical in shape. It attaches to the nose piece at one end and contains the eyepiece lens at the other.  Another name for it is an eyepiece tube or body tube.  It joins the objective and eyepiece lenses.  Inside this tube, the light from the objectives will curve.  They are movable in binocular microscopes, allowing the observer to modify the eyepiece for optimal visibility.
2. Arm- is the component that joins the microscope's base to the head and the eyepiece tube to the base. It serves as both a support for the microscope's head and a carrying aid. Some top-notch microscopes have an articulated arm with many joints, which gives the microscopic head more movement for improved viewing.
3. Base- Supporting the entire microscope structure, the base is the lowest component. It gives the microscope stability. The base is equipped with electrical wiring systems, light switches, and illumination.

Optical parts of a microscope and their functions -

A specimen on a slide is viewed, magnified, and imaged using the optical components of the microscope. These components consist of:

1. The eyepiece - also known as the ocular lens, is the component that is closest to the observer's eye. They can be found at the microscope's top. The specimen is viewed in this section. The most popular ocular lenses are 10X or 15X magnification, while these lenses are available in a range of magnification powers from 5X to 30X. For the second time, they enlarge the picture.
2. The eyepiece holder -  is called the eyepiece tube. It holds the eyepiece slightly above the lens of the objective. The eyepiece tube of some microscopes, like binoculars, is flexible and may be turned for optimal visibility at different distances. Monocular microscopes don't have any flexibility.
3. Diopter Adjustment - This control knob, which is unique to the binocular microscope, allows you to adjust the focus on one eyepiece. It is employed to compensate for and correct for any visual impairments between the viewer's two eyes.
4. Nose piece - The circular, moveable nose piece is where all of the objective lenses are kept. Another name for it is the rotating turret. It sits just above the stage and is attached to the body tube. The magnification may be adjusted by rotating it either clockwise or counterclockwise. A change in the objective lens causes the magnification to alter. 
5. Object lenses - 
1. The lens nearest to the specimen is the objective lens. The nosepiece is fitted with these. Three to four objective lenses with varying magnifications—4X, 10X, 40X, and 100X—are included in a typical microscope. 
2. The light transmitted from the specimen is first received by the objective lenses, which then magnify the image for the first time. 
3. The objective lenses come in various diameters and are color-coded. The lens's power determines its size and hue. 
4. The longest lens will eventually have the maximum power, while the tiniest lens has the lowest power. The 40X and 100X high power lenses may be pushed inward, making them retractable. 
5. Oil immersion objective lenses are used in the majority of optical microscopes with magnifications of 100X or more.
6. Adjustment Knobs - The control knobs used to focus the microscope on the specimen are called adjustment knobs. There are two varieties of these knobs:
1. Fine Adjustment Knob: For fine adjustment, utilize the Fine Adjustment Knob. It is a smaller knob that is used to slowly raise or lower the stage. Every time the fine adjustment knob is turned, the stage moves a very tiny bit. It is employed to make the image sharper. It is primarily utilized while seeing at extreme magnification.
2. Coarse Adjustment Knob: When utilizing low power magnification, the image is focused using the coarse adjustment knob. It is a bigger knob that is used to quickly raise or lower the stage. A coarse adjustment knob is used to quickly raise or lower the stage.
7. Stage - The area where the specimen is positioned for viewing is called the stage. The specimen slides are held in place by stage clips. The most popular kind of stage is the mechanical stage, which enables control over the slides by allowing them to be moved by the stage's mechanical knobs rather than by hand.
8. Stage Control Knobs: These are the control knobs that move the stage in a mechanical manner. There are two knobs: one for forward and backward motion and another for left and right motion. The slide will move inside the field of view as a result.
9. Aperture - The microscope stage's aperture is a hole that allows light from the source to be transmitted to the stage.
10. Microscopic illuminator - Its an example of a light source is a tiny illuminator. A mirror that reflects light from an outside source onto the sample is utilized in certain compound microscopes. Different low-voltage electric bulbs are employed as a continuous light source in other optical microscopes. Tin-halide lamps, mercury vapor lamps, tungsten-halogen lamps, 75-150W xenon lamps, and others are often used illuminators. The selection of bulb types is determined by the wavelength and intensity requirements for illumination.
11. Condenser - This tiny part is actually super important for getting those really clear, sharp images, especially when you're pushing the magnification past 400X. Think of it this way: the stronger your condenser, the sharper everything will look. And if you're checking out some of the fancier microscopes, you'll often find they've got an Abbe condenser built in, which lets you zoom in incredibly close, sometimes even up to 1000X!
12. The Diaphragm (or "Iris") - You know, the diaphragm—sometimes called the iris—is a really important part of the microscope, typically found right under the stage. Its main job? To control exactly how much light hits your specimen. It's totally adjustable, so you can tweak both the brightness of the light and the size of the light beam shining on your sample. On some of the fancier, high-quality microscopes, the diaphragm actually comes paired with an Abbe condenser. When they work together, they do an even better job of controlling both the focus and intensity of the light reaching your specimen.
13. Condenser Focus Knob - Then there's the condenser focus knob. This is simply the knob you use to move the entire condenser up or down. Why do that? Well, it helps you fine-tune the focus of the light onto your specimen, which is crucial for getting a clear view.
14. Abbe Condenser - Now, the Abbe condenser is something special, usually found on those higher-end microscopes. What makes it stand out is that it's designed to be movable, which is key for achieving really high magnifications—we're talking well above 400X! These top-notch microscopes typically have a higher numerical aperture than their objective lenses, allowing for even better resolution.
15. The Rack Stop - This little safety feature, the rack stop, is super important! It essentially controls how high the microscope's stage can go. This prevents the objective lens from crashing into the specimen slide, which could easily damage your sample or even the lens itself. So, in short, it makes sure the slide doesn't come up too far and hit the objective lens.
16. Light Switch - Pretty straightforward, the light switch is exactly what it sounds like – an electrical control. You just flip it to turn the illuminator (the light source) on or off. Simple as that!
17. Brightness Adjustment - The brightness adjustment system is what lets you control how intense the light is. It works by regulating the voltage sent to the light bulb, which in turn brightens or dims the light hitting your specimen.

How Do Microscopes Operate?

• A thin specimen with a slide is put on the microscope's stage in a standard light microscope.
• A light beam is directed towards the specimen using the condenser.  The objective lens captures the light that was transmitted from the specimen.  The transmitted rays disperse as they go through the objectives, creating the impression that they originate from the larger objects. 
• The eyepiece lens is then the focus of the light.  The pre-magnified image from the objectives is further magnified by this lens. 
• At last, a significantly magnified image is seen.