The two main things that make a light microscope different from an electron microscope are the source of light and the type of lens.
Source of illumination: This is the part of a microscope that makes the object or specimen easy to see and makes it brighter.
Lens: It is used in a microscope, which can be different depending on the type, and its main job is to make the image bigger.
In the light microscope, the image is made by a direct source of light waves. In the electron microscope, the image is made by a beam of sped-up electrons. In a light microscope, the lens is made of glass and has an eyepiece, an objective lens, and a condenser lens. The electron microscope uses the electromagnetic lens, which is a combination of the condenser lens, the objective lens, and the projector lens. Here, we’ll talk about the main differences between the light microscope and the electron microscope and show you a chart that shows how they compare.
What is a Microscope?
A microscope is a piece of equipment with a set of lenses that lets us see an object or specimen in a bigger size. Without a microscope, we wouldn’t be able to look at both the inside and outside of the specimen. This tool lets us do that.
The word “microscope” comes from the words “micro,” which means “minute things,” and “scope,” which means “to look at.” So, the microscope is a tool that lets us look at or see microorganisms that are too small to be seen with the naked eye. Microscopy is the study of living things with the help of a microscope.
What Is A Light Microscope?
A compound microscope is another name for a light microscope. The optical microscope lets you see a small object through clear glasses and a projection screen by shining light on it.
The device is often used to look at microorganisms in school, college, and university labs. It has many parts that each do something different.
Objective lenses are a common part of a light microscope. The eyepiece, diaphragm, light source, mirror, condenser, resolving nose piece, stage clips, tube, objective, coarse focus, and fine focus.
The optical microscope is simple and easy to use, which is good news. But compared to the electron microscope, the power of resolution is usually low.
Some common types of compound microscopes on the market right now are the ultraviolet microscope, the bright field microscope, the confocal microscope, the darkfield microscope, the differential interference contrast microscope, the phase contrast microscope, and the fluorescence microscope.
Diagram of a Light Microscope
It has a number of components, such as:
- Eyepiece lens. It is closest to the observer’s eye. It contains one or more lenses. The picture is amplified by the objective lens and the eyepiece before being observed by the observer. Its main job is to change the objective lens’s created actual intermediate expanded image into an enlarged virtual image.
- Lens tube. Its length, which might vary depending on the type of microscope, is roughly 160 mm and it contains the eyepiece.
Objective revolver. It carries numerous objective lenses with variable magnifying power or capacity. Depending on the desired level of specimen magnification, one can spin or rotate this.
- Objective lens. The lens closest to the specimen or object collects light rays, amplifies the image by reflecting them to the numerical aperture, and then provides a clear view of the object.
- Clip. It keeps the glass slide with the specimen sample within.
- Microscope stage. It offers a surface area so that the object slide can be moved to the desired location or in accordance with the area of the specimen that the user wants to examine or see.
- Condenser. For proper visibility, it projects back to the specimen the light that strikes it and collects it.
- Fine and coarse focus. By changing the microscope stage, both of these control the separation between the object and the objective. After the fact, both fine and coarse focus can be changed to alter the image’s sharpness.
- Diaphragm. By preventing the image from overshining, it controls the diameter of the light.
- Light source. The light microscope uses LEDs that resemble light bulbs for this.
- Stand or body. It holds every part of the microscope.
- Base. It helps keep the microscope stable.
Types of Light (compound) Microscope
- Differential Interference Contrast Microscope.
- Confocal Microscope.
- Bright Field Microscope.
- Dark Field Microscope.
- Ultraviolet Microscope.
- Phase Contrast Microscope.
- Fluorescence Microscope.
Advantages of a Light Microscope
- Very inexpensive
- Appropriate for both living and dead specimens
- The color of objects remains as it was originally
- The picture is clearly visible.
- There is no need for a high power voltage.
- Magnification has no impact.
Disadvantages of a Light Microscope
- Low magnification power and rotation
- The preparation of the specimen is challenging.
- Does not give specific details about an atom
- The path of a light beam is not always straight.
- Not the best for tiny organisms
What Is An Electron Microscope?
In contrast to a light microscope, which uses visible light to see microscopic things, an electron microscope uses electrons. The tool is frequently used by scientists to examine an object’s finer characteristics.
When compared to a light microscope, an electron microscope has a higher level of resolution power. This is one of the factors contributing to their appeal.
Focused ion beams, scanning transmission electron microscopes, scanning electron microscopes, transmission electron microscopes, and electron microscope are a few of the common types of electron microscopes.
Due to its high power resolution capability, an organelle’s features can be seen under an electron microscope. Compared to visible light, the wavelength of the electrons is short.
Diagram of an Electron Microscope
It consists of the following elements:
- Electron gun. It makes the beam of sped-up electrons by heating the tungsten filament to between 100 and 1000 kV.
- Condenser lens. There are two magnetic condenser lenses that focus the light on the sample.
- Objective lens. Magnetic objective lenses focus the electron on an object and create the first real intermediate image that is up to 2000 times bigger than the original.
- Projector lens. It makes the real intermediate even bigger, up to or more than 240,000 times bigger.
- Viewing screen. A zinc sulphate fluorescent screen or a photographic plate is used to see the image on an electron microscope.
- Camera. It’s the charged coupled device, and it’s under the screen where you view things.
- Specimen holder. The sample is kept in a thin layer of carbon or collodion, which is held in place by a metal grid.
Types of Electron Microscope
- Scanning Transmission Electron Microscope.
- Scanning Electron Microscope (SEM).
- Focused Ion Beam and Electron Microscope.
- Transmission Electron Microscope (TEM).
Advantages of an Electron Microscope
- Possesses the best rotating power.
- Magnification is 10,000 times greater.
- Give a 3D illustration
- provide you greater clarity because of shorter wavelengths
- Give specific details about a specimen.
Disadvantages of an Electron Microscope
- provide photographs in black and white only
- arduous specimen preparation
- Very difficult to operate
- Too pricy to purchase
- appropriate for dead specimens
- vulnerable to radiation leaks
Key Differences Between Light Microscope and Electron Microscope
- One distinguishing feature between a light and an electron microscope is that the former employs a light source and the latter an electron beam.
- Low magnification and resolving powers of 1000X and 0.2m, respectively, are displayed by the light microscope. An electronic microscope, on the other hand, has a high magnification and resolution power of 10,000X and 0.001mm.
Through the light microscope’s eyepiece, the object is clearly apparent. The electron microscope, in contrast, uses a fluorescent screen to observe the item in greater detail.
- Due to its complicated architecture, an electron microscope takes more power and technical expertise to operate, whereas a light microscope needs less power and is simpler to use.
- A light microscope lacks the vacuum system, tungsten filament, cooling system, and radiation leakage that are found in an electron microscope.
- In contrast to the electron microscope, sample preparation is simple in a light microscope.
- In a light microscope, thick specimens up to 5 m can be seen clearly, but an electron microscope can only see thin specimens up to 0.1 m.
- Chemical dyes are applied to the specimens to stain them, which produces colored specimens and adds contrast to the microscopic image. In contrast, a specimen in an electron microscope is covered with heavy metals that draw the electron beam, producing a specimen that is black and white.
- There are four main types of light microscopes: bright field, dark field, phase contrast, and fluorescent field. There are three different types of electronics microscopes: TEM (Transmission Electron Microscope), SEM (Scanning Electron Microscope), and STEM (Scanning Transmission Electron Microscope).
Similarities between Light and Electron Microscope
- Both are employed for seeing tiny items that are invisible to the eye.
- Both call for staining the specimens to prepare them.
- Both are applied in research.
- Both are applicable to microphotography.
- Both adhere to Abbes law.
Although both types of microscopes are significant and have advantages and disadvantages, today’s scientists primarily use electron microscopes in research labs to study organisms in detail, while light microscopes are more commonly used in classrooms, colleges, and pathology labs to view organisms that can be seen clearly through them.
Even before the invention of the microscope, scientists were able to explain diseases like tuberculosis, typhoid, dysentery, measles, and others as well as their origins and treatments.