Better insight into microscopes

What is microscope? A device with which we can see objects that are too small to be seen with the naked eye. It is typically used in science labs or classrooms to visualize all kinds of small objects such as cell, microorganisms, tissue structures, materials, etc. Microscopes magnify images and add contrast to images. To make this possible, microscopes are made up of lenses, each lens having its own magnifications and focusing capability. Microscope is a combination of two words: “micro” meaning small or tiny, and the word “scope” meaning seeing or observing. Microscopes have many main fields of application, mainly scientific fields such as microbiology, cell biology, human physiology and medicine or reproductive medicine. Of course, it has many more areas of application that this, just like forensic science, agriculture, semiconductor, nanotechnology, where the development of nanomaterials like carbon nanotubes cannot advance without electron microscopes.

There are many types of microscopes, although most people think of them as a complex model from the laboratory department. These tools are used by researchers, technicians, and students every day, according to their need or depending on their resources. Because some copies are capable of higher resolution against magnification, or vica versa. There can also be a huge difference between their costs.

Simple microscopes are the first, they were created by Anton van Leeuwenhoek in the 17^th century, his solution was a convex lens, which he combined a simple holder, it was essentially a magnifying glass, because it enables 200-300 times magnification. It was simple, but Leeuwenhoek was able to collect information about biological samples, including differences in the shape of red blood cells. It is not really used nowadays, as compound microscopes appeared with the introduction of the second lens.

Compound microscopes with two lenses offer better magnification because the second lens magnifies the image. These are already bright, which means that the pattern is illuminated from below. Compound microscopes can be monocular and binocular. The devices already supply 1000 times magnification, which is certainly considered high, but the resolution remains low. The high magnification allows users to get a close look at objects that are too small to be seem with the naked eyes. In most cases, the pattern is small and have some degree of transparency. Because compound microscopes are useful but relatively inexpensive, they can be used anywhere from research laboratories to high school biology classrooms without any problems.

The next microscope, the stereo microscope, or the dissecting microscope, which can magnify up to 300 times. These microscopes are used when objects are too opaque for binocular microscopes or too large for compound microscopes, as they do not require slide preparation. Although its magnification is relatively low, it is still useful. They can provide close 3D images of the surface textures of objects, as well as allowing users to manipulate objects while viewing them. These microscopes are also used in biological and medical applications, as well as in the electronics
industry, such as watchmakers.

Unlike the stereo microscope, the confocal microscope no longer uses light to create image, but laser light to scan stained samples. The samples are prepared on a slide, then with the help of a dichromatic mirror, the device creates an enlarged image on the computer screen. Furthermore, operators can create 3D images by stitching together multiple scans. Like compound microscopes, they are capable of high magnification, but in contrast, their resolution is much better. It is used in cell biology and medical applications.

Our next subject is the scanning electron microscope, or SEM for short, which uses electrons instead of light to create images. The samples are scanned in or near a vacuum, so they must be specially prepared, so they are first dehydrated and then coated with a thin layer of a conductive material like gold. After the item is prepares, it is then places in a chamber, the SEM produced a 3D black and white image on a computer screen. SEMs, which ensure proper control of the degree of magnification, are used by physical, biological, and medical researchers to examine a wide range of samples ranging from insect to bones.

Similar to scanning electron microscopes, the transmission electron microscopes, or TEM for short, also uses electron to produce magnified images and is scanned in a vacuum, so they must be specially preparing. However, unlike SEM, TEM uses slide preparation to obtain 2D samples, making it much more suitable for viewing objects with some degree transparency. It offers a high degree of resolution and magnification, making it useful in biological and physical sciences, as well as in metallurgy, nanotechnology, and forensic analysis.

Today, microscopy is essential in medicine, for making new cell discoveries, and the types of microscopes can be classified based on the physical principles used for imaging.

For more information check the link below:

https://sciencing.com/difference-glass-compound-light-microscope-8611655.html

Information researched by Dezső Sándor