Microscopes are a part of everyday life for many of us. You can find these tools in schools, hospitals, or even at home for simple entertainment.
The microscopic world has proven to contain some of the most beautiful things Nature has for us, after all. But did you know there are nearly a dozen different types of microscopes out there, each with their own special uses?
Read on to learn about some of the many ways we can view the microscopic world.
Types of Microscopes
1. Compound Microscope
By far the most popular kind of microscope, the compound microscope uses two lenses to achieve up to 1000x or 2000x magnification. Specimens are backlit and may be viewed using either a monocular or binocular eyepiece.
You can find compound microscopes in one form of another in homes, science labs, and even hospitals. Oddly enough, it was the work of Robert Hooke using one of the first compound microscopes that inspired the invention of the simple microscope.
2. Confocal Microscope
Providing higher resolution than a compound microscope, a confocal microscope allows for 2D or 3D images of the subject matter. A slide containing a dyed sample is inserted into the microscope. The sample is then scanned using a laser light and, with the aid of a dichromatic mirror, appears on a computer monitor.
As laser light penetrates deeper than regular light, the user can get either a highly detailed look at opaque objects as far as the laser can penetrate, or the interiors of more translucent objects. This type of microscope is useful in cell biology, as well as various medical applications.
3. Fluorescence Microscope
A high-energy, short wavelength light is used for this microscope, exciting the electrons of certain molecules. These electrons shift into a higher orbit briefly. When they settle back, they emit a low energy, low wavelength (visible) light.
The amount of spatial resolution is limited, but the microscope is powerful enough to detect the presence of a single molecule. While fluorescence was first described in 1852 by Sir George G. Stokes, its almost essential use in biology and biomedical science wasn’t explored until the 1930s.
4. Scanning Electron Microscope (SEM)
An electron microscope uses electrons instead of light, allowing for incredible resolution. Scanning electron microscopes are used exclusively to view the surface of an object.
The object must be dehydrated, then lightly coated in a highly conductive material such as gold or palladium. A beam of focused electrons is bounced off of the specimen in a manner similar to sonar.
The resulting data is translated into a black and white image on a computer screen at a resolution chosen by the user. These microscopes have a wide range of scientific uses in both physical and medical science.
5. Scanning Probe Microscope
This optical microscope uses a physical probe to examine the sample. The scan is done using a raster (line by line) method. As a result, the scans can take some time but produce high-quality computer images.
These have a more limited magnification than electron microscopes but do not require a vacuum. Another great advantage is that the sample can be stimulated and the reactions or response may be observed, as well as the specimin’s properties.
In use since 1986, scanning probe microscopes are not only valued in the fields of biology and chemistry, but also physics.
6. Simple Microscope
As the name implies, this is the most basic type of microscope. It was created in the 17th century by Antony van Leeuwenhoek and involves a single convex lens and specimen holder.
Capable of magnifying 200x to 300x. This form of microscope is rarely used today.
7. Stereo Microscope
Sometimes referred to as a dissecting microscope, this type overcomes the need for slides, allowing the user to study opaque objects. While the magnification is only 300x, users can view and even manipulate 3D objects.
Stereo microscopes are used not only for biological and medical science, but can often be found in electronic fields such as circuit making. The tool works by having two optical paths set up at different angles, allowing for a detailed surface view of even living or inanimate objects.
8. Transmission Electron Microscope (TEM)
The counterpart to the SEM, a transmission microscope uses ultra-thin samples prepared on a slide. Once coated in a high conductivity material, the sample slide is scanned in a vacuum.
This allows the electrons to pass through the object with the beam being reflected by the denser parts. As a result, the black and white image allows for a high degree of magnification and resolution.
These microscopes are useful in a wide range of fields, from physical and biological science to forensics. It is also extremely useful in the development of nanotechnology and metallurgical analysis.
9. UV Microscope
Using ultraviolet light produced by a mercury arc or xenon burner, UV microscopes are able to get twice the resolution of visible light microscopes. Images are either photographed or scanned using a digital sensor to avoid harming the observer’s eyes.
10. X-Ray Microscope
Used in the observation of living cells, X-ray microscopes use electromagnetic radiation to create highly detailed images. This type of microscope is popular in both biological research and metallurgy.