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Light microscopy is a great hobby to get into if you are interested in learning more about the world around you.
Compared to some other microscopes on the market, light microscopes are some of the most accessible instruments.
Not only is it easy to find light microscopes, but they are some of the most affordable models out there.
While getting into electron microscopy is almost impossible as a hobby, you can easily make a hobby out of light microscopy.
If you are interested in buying your own simple or compound light microscope, this guide will be for you.
We will cover what a light microscope is and how it works. Furthermore, find out what you can see with light microscopes and learn how to use one.
This guide will cover everything you need to know about light microscopy, whether you want to pick it up as a hobby or even a career.
Let’s dive into it.
What Is a Light Microscope
A light microscope is an optical instrument that uses light to magnify an object.
The instrument uses multiple glass lenses and a beam of light to illuminate the specimen and magnify it. You can view the specimen by looking through the eyepiece lens.
Light microscopes are usually tabletop instruments that are not as heavy compared to other, more complex microscopes.
You can typically find a light microscope in school classrooms or university laboratories.
Researchers use light microscopes to study various small objects such as cells, organelles such as the mitochondria, and most kinds of bacteria.
However, light microscopes have limitations. You will not be able to see proteins, viruses, small bacteria, macromolecules, or atoms.
In general, most light microscopes have a maximum magnification of around 1000x.
In contrast, some other microscopes, such as an electron microscope, can magnify an object up to 1,000,000x.
There are a few different types of light microscopes, which we will discuss further in-depth down below.
First of all, the instrument can either have a monocular or binocular head (it will either have one or two eyepieces).
There are about six main kinds of light microscopes called the simple light microscope, compound light microscope, phase-contrast, ultraviolet, fluorescence, and confocal microscope.
How Do Light Microscopes Work
Light microscopes may look like complex machines when in reality, these instruments produce a magnified image in only a few basic steps.
- The microscope sends light through a path and transforms it into a tight beam. Before anything else, the microscope needs to form a straight beam of light. The machine does this by sending light from the illuminator through a lens/path of lenses.
- The beam of light passes through the specimen. Once the microscope converts the light into a tight beam, the light illuminates the specimen, passes through it, and creates an image.
- The microscope sends the image through a series of lenses to magnify it. Only after the light passes through the specimen can it be magnified. The microscope sends the image through either one or two lenses, depending on the model, and produces the final image.
- The final image is sent to the eyepiece. After the microscope magnifies the image, it finally reaches the eyepiece lens for the user to see.
While each model may differ a bit, these are the four main steps that occur in almost every light microscope.
What Can You See With Light Microscopes
You can see a lot with light microscopes. Some models can support magnification levels of up to 1000x.
While this magnification power may pale in comparison to other kinds of microscopes, you will be surprised by how much you can still see with a light microscope.
Some specimens and objects you can study with a light microscope include bacteria, organelles, chromosomes, blood, protists, and thick tissue sections.
You can also observe things such as plant cells, pond water, insects, and other specimens similar in size.
While you won’t be able to see atoms, molecules, or viruses, there are many different things you can observe. Simply take a walk outside and find things to study, such as a piece of grass or a feather.
The great thing about light microscopes is that it is easy to prepare your own slides with whatever you want to observe close-up.
How To Use a Light Microscope
While there are a few different kinds of light microscopes, you only need to know one basic set of steps to become familiar with the instrument.
This section will cover how to use a light microscope in nine easy steps.
While these steps may differ slightly between one microscope and another, the basic steps should be relatively similar.
- Connect the light microscope to a power source. First things first, connect the machine to a power source. If you are using a light microscope that does not have a powered bulb but a mirror instead, make sure to position it in an area with a good amount of light.
- Make sure to set the lens as the lowest powered objective lens. If you are using a microscope with multiple lenses, maneuver the nosepiece to use the lowest power objective lens.
- Prepare your slide and mount the specimen on the stage. Carefully prepare your slide, cover the slide with a coverslip and mount it on the stage.
- Make sure to position the slide properly and securely. Make sure that the specimen is positioned in the center and directly underneath the objective lens. Once it is in position, use the metal clips to secure it into place.
- Look through the eyepiece and focus the specimen. Use the coarse adjustment knob and fiddle with it a bit until the specimen is as clear as possible. Make sure that the objective lens does not hit the specimen during this process.
- Adjust the amount of light. Once the specimen is in focus, use the condenser to increase the amount of light shining on your specimen.
- Adjust the fine adjustment knob. After adjusting the light, you will use the fine adjustment knob to tweak the focus of the image a bit more. Adjust the focus until you see the clearest image possible.
- Observe your specimen on the lowest objective lens. Now that you have adjusted everything take some time and observe your specimen.
- Re-examine the specimen on higher power lenses. Once you finish examining the specimen using the low power objective lens, switch to a higher power lens. You will need to readjust the light and focus each time you switch lenses.
Types of Light Microscopes
Now that we know how light microscopes work let’s look at all of the different types of light microscopes.
This section will review simple and compound light microscopes, as well as phase-contrast, ultraviolet, fluorescence, and confocal microscopes.
Simple Light Microscope
The most basic type of light microscope is the simple microscope. These models only have one lens compared to multiple sets of lenses that other microscopes have.
For this reason, simple microscopes cannot support a high magnification power.
Furthermore, while some simple microscopes use a powered light, some models don’t come with a light. In these cases, you will need to use natural light to illuminate the specimen.
Compound Light Microscopes
Unlike the simple microscope, compound microscopes have two lenses, including an eyepiece lens and an objective lens.
These models also typically have a powered lightbulb that illuminates the specimen from underneath.
Compound light microscopes can handle higher magnification powers than simple microscopes can.
These models will have a maximum power of 1000x. However, the resolution is quite low.
Phase-Contrast Microscopes
Phase-contrast microscopes are another type of light microscope. These models use powered light, condenser lenses, and phase-contrast objective lenses to produce images with high contrast.
When using phase-contrast microscopes, the specimen will look darker or lighter than its background, making it easy to see.
Ultraviolet Microscopes
These models utilize UV technology to produce higher-quality images with high resolution and magnification power.
The main components of these microscopes consist of UV light, optics, and cameras.
Fluorescence Microscopes
Fluorescence microscopes are less common to find since they are very costly.
These models utilize high-intensity light and fluorophore (a type of fluorescent substance) to illuminate the specimen.
The microscope’s light source will send fluorophores onto the specimen, causing it to produce longer wavelengths.
The longer wavelengths are how the microscope produces an image of the specimen.
Confocal Microscopes
Confocal microscopes have a few similar characteristics that fluorescence microscopes do since it uses fluorescents as well.
These models produce high-quality images with high resolution and magnification.
The instrument emits a laser onto the specimens and then collects data. The microscope then produces an image from the information it gathered with the laser.
Why Are Light Microscopes Used
While light microscopes may not have as many features and power as other models on the market, there are a few good reasons why these kinds of microscopes are still popular today.
Price
The first reason why people use light microscopes is because of the price. Unlike other microscopes, which can cost thousands of dollars, there are plenty of high-quality light microscope models for under $1000.
This factor is the main reason why you can find these kinds of microscopes in schools, universities, and just about any research laboratory.
While these models are not the highest-quality, they can still do a lot for the price.
Size
Another main benefit of light microscopes is their size. A typical light microscope you will find will be a desktop microscope.
While they may be a bit heavy, a high school student could easily move the machine around the classroom (carefully, of course).
Ease of Use
Light microscopes are also very easy to use. A student only needs a bit of instruction to figure the machine out.
This is what makes them great for the classroom, universities, and research labs.
Unlike other microscopes, you don’t need to take special training to use light microscopes.
For Studying a Variety of Specimens
Even though light microscopes are not the most powerful tool out there, you can still use them to study a large variety of specimens.
Combined with its positive attributes like the low price, size, and ease of use, it is easy to see why these instruments are so popular.
One of the main things that researchers use light microscopes for is to study living cells.
Scientists will also use these models for observing bacteria and organelles such as the nucleus and chloroplasts of the cell.
Maintenance
Even though light microscopes are on the lower end of the price range, they are still very expensive and complex machines.
To upkeep the machine and prevent damage, you will need to know how to properly maintain it. Let’s look at a few tips on how to do this.
- Handle with care. Hold the microscope by the arm and base when carrying it, and always use a travel case when traveling.
- Store properly. Store the microscope in a dry and well-ventilated area and always put a dust cover over it.
- Service the microscope every 200 hours of use. To prevent costly repairs, make sure to have a professional service your microscope about every three years or after 200 hours of use.
- Clean the instrument with the proper materials. Always use lens cleaning wipes and lens cleaning solution to clean the microscope.
- Always have the user’s manual on hand. There will be times when you will have to make some adjustments to your microscope. Refer to the user’s manual to avoid damaging the machine.
Conclusion
We hope that this guide has helped you learn everything you need to know about light microscopes.
A light microscope is an optical instrument that uses light to produce a magnified image of an object.
Whether it is with natural light or artificial light, the microscope uses a series and lenses and a light source to illuminate the specimen.
You can see a variety of specimens up close with light microscopes. Scientists use these machines to observe living cells, insects, chromosomes, bacteria, blood organelles, and other objects.
Using a light microscope is not too complicated. The basic steps involve plugging it in, setting the objective lens, preparing and mounting your slide, and adjusting the light and fine adjustment knob.
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