All About Lab Microscopes
Microscopes are a critical part of most laboratory environments. Having evolved steadily since the 16th century, these ubiquitous instruments have given us windows into universes and provided insight in ways that still surprise us today. Here, we’ll examine what makes microscopes, in their various forms, crucial to research, diagnosis, and other applications in the lab, the classroom, and beyond.
The History of Laboratory Microscopes
As we covered in our cell counters blog, early versions of lens-based microscopes appeared in the late 13th century as an extension of the burgeoning field of eyeglasses. Before that, dating back approximately 4000 years, the Greeks used water globes as magnifying glasses. However, in the 13th century, we began using lenses more widely.
In 1590, Zacharias Janssen and a partner, both lensmakers in the Netherlands, are often credited with crafting the first compound microscope that used more than one lens to increase magnification power. While better than a single lens, it only provided 10-20 times the magnification power.
In 1665, with the new world opening, Robert Hooke, an English physicist, used the compound microscope to examine the rectangular structures in a slice of cork. They reminded him of monastery rooms, known as cells, and so he pioneered the term in his book, Micrographia.
Improving Magnification
The simple microscope was improved in the mid to late 1600s when a Dutch inventor named Antoine van Leeuwenhoek found that by rounding the edge of a lens through hand grinding and polishing, you could increase the magnification by nearly 270x. Using this improved method to examine blood cells and spermatozoa, the use of microscopes to view biological structures helped advance the field of science.
Microscopes remained essentially unchanged for around 200 years after this, until the 1830s, when Joseph Jackson Lister and William Tulley developed a microscope that corrected two significant problems with magnification: image blurring and chromatic aberration. Once these problems were solved, the microscope made its way into an increasing number of laboratories, and cells became the focus of studies. The 20th century introduced the electron microscope, which utilizes electrons instead of light to produce images. This shift enabled significantly higher resolution. However, as different needs arose, additional improvements were made over the years, including more efficient condensers to focus the light, novel and improved light sources, and stronger lenses. Let’s look at various microscopes you may find in a lab today.
Types of Microscopes
Microscopes vary in complexity, from simple, hobbyist-purpose microscopes that are little more than a magnifying glass to highly complex fluorescent microscopes and electron microscopes that can see structures 1000x more detailed than a light microscope.
Compound Microscopes are the most common type, for good reason. They utilize multiple lenses to achieve high magnification and are widely used in biological research. Stereo Microscopes, also known as dissecting microscopes, feature two optical paths at slightly different angles to provide a 3D view of specimens. Inverted microscopes view an object from below, making them ideal for examining living samples in a petri dish rather than on a slide.
A high-powered microscope, known as a metallurgical microscope, can achieve magnifications of up to 200x to 500x to view opaque samples. This enhanced magnification enables users to detect micron-sized cracks in seemingly smooth surfaces, such as metal or paint, with greater precision. It allows industries to examine the structure of materials, including glass, polymers, ceramics, liquid crystals, and other substances.
Geologists and Chemists may opt for polarizing microscopes. Equipped with polarizing filters, these microscopes are used to observe materials that exhibit optical anisotropy, such as minerals and crystals.
Microscope Techniques and Other Microscopes
Phase Contrast Microscopes enhance the contrast of transparent specimens without the need for staining. This technique is beneficial for observing living cells and tissues, allowing researchers to see details such as cell structure and movement in their natural state.
Fluorescence Microscopes use dyes or proteins that emit light when excited by specific wavelengths. They are invaluable for studying cellular processes, molecular interactions, and protein localization. Fluorescence microscopy is widely used in cell biology, microbiology, and biochemistry. This dye-based imaging technique is also popular, utilizing specialized imaging systems.
Electron Microscopes
Transmission Electron Microscopes (TEM) offer extremely high magnification and resolution by passing electrons through a thin specimen. They are crucial in materials science and biology. Scanning Electron Microscopes (SEM) scan a specimen’s surface with a focused electron beam, providing detailed images of surface structures. Atomic Force Microscopes (AFM) use a probe to scan the surface of a sample at the atomic level, providing high-resolution topographical maps.
Manufacturers of Laboratory Microscopes
Nikon
Known for their high-quality optical systems, Nikon microscopes are used extensively in both research and clinical settings. Their range includes everything from basic compound microscopes to advanced digital imaging systems.
Olympus (Now Evident Scientific )
Olympus Microscopes offers a diverse selection of microscopes suited for various applications, including biological research, industrial inspection, and material science. Their innovations in optics and imaging technology are well-regarded.
Leica Microsystems
Leica is renowned for its precision and advanced imaging capabilities. Their microscopes are designed for a wide range of applications, from life sciences to industrial analysis, and they are known for their ergonomic design and user-friendly features.
Zeiss
Zeiss microscopes are celebrated for their superior optical quality and durability. They offer a range of solutions, from basic educational models to high-end research instruments.
Other name-brand companies, such as Fisher Scientific, Thermo, AMG, Laxco, and VWR, offer trinocular heads for digital cameras, Including Inverted and upright, compound, and stereo models. If you need it, there’s a microscope to fit it. The hard part is narrowing the field of options. Some are even modular and can be upgraded as research advances.
Conclusion
Laboratory microscopes have undergone significant evolution since their inception. From the early days of globes filled with water to simple lenses to today’s sophisticated electron and scanning probe microscopes, these instruments continue to be essential tools in scientific research and industry.
Over the years, we have carried a wide range of name-brand and style laboratory microscopes, featuring varying power levels and advanced options. Our many years of experience mean we know how to service and maintain microscopes that come through our doors, so you can be sure that what makes it to the website is ready to go when you are. If you don’t see what you need, let us know. We may have more in the future and can help you identify the most essential features for your lab. Contact us today to learn how we can assist you.
