Microscopes are one of the most basic, foundational building blocks of the scientific process. The ability to zoom in on viruses and bacteria has played a hugely pivotal role in advancing chemistry, medicine, and other scientific domains across the past century and into today. The history of microscopes would take up an entire article, which is why, in this article, we’re going to focus on more of the structural components and practical applications of these ingenious devices. In particular, we will take a look at at the many different types of microscopes.
First, however, we want to introduce you to the work we do and why we do it. Here at Optical Mechanics, we provide some of the best optical equipment on the international market today. We’re highly invested in education, have an all-star staff of the best experts in the field, and aim to be the top retailer of optical equipment, emphasizing being an excellent resource for all our customers.
Now that you’re a bit more familiar with why we’re here let’s go into the different types of microscopes. We’ll include simple and compound (remember high school chemistry?), electron, and stereo microscopes. We’ll also talk about specialty microscopes, which include fluorescence, confocal, and scanning probe microscopes. We describe them in further detail below, along with the applications of microscopes, their functionalities, and, as appropriate, their basic anatomies.
A simple microscope uses a single lens. Pretty simple, right? The lenses are convex, which means that they curve outward. These lenses have a small focal length, meaning they can only zoom in so far.
The various parts of the microscope are best diagrammed but can be summarized as the eyepiece – where you view all of your specimens – at the top; the nosepiece, which holds the two objectives (the actual magnifiers); the specimen stage and aperture diaphragm, where you place the material you’re studying; the body, which refers to the essential structural components which hold the microscope parts together; and finally, the base, which is self-explanatory.
So, what are the functions of simple microscopes? Well, watchmakers and jewelers use them frequently, for one. They use simple microscopes to zoom in on the smallest pieces of their watch material or jewelry. Most middle and high schools use simple microscopes. Dermatologists look at skin samples using simple microscopes as well. This list is certainly not exhaustive, but these are the primary applications of these microscopes.
Simply put, a compound microscope has multiple lenses, an objective lens, and ocular lenses, and some compound microscopes have multiple other lenses on top of these basic two.
There are some similarities between the simple and compound parts, but there are also key differences. The compound microscope has more detail and more overall components. To zoom in and out at varying degrees of granularity, you have the fine adjustment knob and coarse adjustment knob. The inclination joint is near the base, which connects the body to the base. Compound microscopes also have mirror bases that reflect the image up to the lenses for increased visual precision. The nosepiece in compound microscopes rotates, unlike its simple counterpart. While the objective and the specimen stage are the same, compound microscopes have a condenser below the stage.
So, what are the compound microscope applications and functionalities? Well, they differ from simple ones regarding the material being studied. For instance, compound microscopes are used to study very granular levels of viruses and bacteria. You would also find a compound microscope in a forensics lab, and metallurgists (metal workers) use compound microscopes.
Electron microscopes are vastly different from the two we described above. In these, the source of the beams is actually accelerated electrons. These microscopes’ high resolutions are measured in nanometers, one of the smallest measurement units. Two subtypes of electron microscopes exist: the transmission electron microscope (TEM) and the scanning electron microscope (SEM). To familiarize yourself with the anatomy and basic structure of both types of microscopes, it’s best to look at a diagram.
So, what are electron microscope scanning applications, and what are the electron microscope transmitting applications? They both have QC (quality control) uses in industrial settings. Both are also used to study crystals and metals, but at a much finer level than simple or compound microscopes. With SEMs specifically, materials scientists use them for research, QC, and failure analysis. With TEMs, biological scientists use them particularly to study thin specimens such as cells and tissues.
While all the abovementioned microscopes operate in 2D, stereo microscopes offer a 3D image of various samples. Also known as a dissecting microscope, it has two eyepieces for two separate lenses, so each eye has two optical paths.
So what are some useful applications for dissecting microscopes? They’re primarily used for 3D material, such as historical coins and other artifacts. You can also find stereo or dissecting microscopes in microsurgeries, which require a focused, 3D look at surgical sites in real time. Scientists also study crystals with stereo microscopes, with more applications than simple or compound microscopes alone.
Scanning Probe Microscope
A scanning probe microscope is the most granular microscope, studying materials at nanoscale levels. What does this mean? Scientists here study biological and chemical processes such as reaction time or behavior, and these microscopes are conducive to this kind of tiny, real-time activity.
A fluorescence microscope is basically an enhanced version of a conventional light microscope. They use a higher-intensity light source to activate any given sample. This high-intensity beam is used with a lower-energy light beam with a longer wavelength. These two processes coincide to produce a brilliantly illuminated and magnified sample.
The light source for confocal microscopes is a laser, so it has an incredibly intense and highly concentrated beam of light. They isolate a plane of a thick sample by “slicing into it” via a laser beam and using natively-fluorescent molecules in that plane while shutting down all non-fluorescent material.
1. What is the difference between a compound microscope and a stereo microscope?
It’s easy to confuse these two types of microscopes. Why? They both have two lenses, so they are both technically compound microscopes. There are some significant differences between these two types, however. For one, a compound microscope is still only primarily used for viruses and bacteria at high levels of focus. Stereo, or dissecting microscopes, on the other hand, are the only types of microscopes out there that are used for 3D purposes. Some of their primary applications include microsurgeries and the analysis of coins or other artifacts.
2. What is the highest magnification of an electron scanning microscope?
SEMs cover a vast range of magnifications and can magnify as high as 1,000,000x, the original size of the sample.
This article was a deep dive into the different types of microscopes available on the market. We examined simple, compound, electron (including subtypes scanning and transmission), stereo, fluorescence, and confocal microscopes. Within each type, we went through basic anatomy where feasible, described the microscopes and what they did, and covered practical applications for each type.
At Optical Mechanics, we emphasize being the best resource, both educationally and equipment-wise, for these different microscopes. We hope you are primed with more education, knowledge, and passion for scientific inquiry. We will take it from there!