Ordinary professional microscopes use optical lenses, which somewhat limits their functionality. Nevertheless, it is precisely such simple devices that are for the most part presented on the market for these devices. For more advanced purposes, professional electronic microscopes are available nowadays that use more advanced zoom technology and display the image on a computer screen.
The importance of this apparatus for modern science cannot be overestimated. With its help, many new bacteria, microorganisms, viruses were discovered, numerous physical laws were examined regarding the molecular and atomic aspects of the material world, etc.
Alternatives
Alternatives to optical devices that do not use visible light include scanning electron microscopy, transmission electron microscopy, and scanning probe.
Normal
An ordinary professional microscope uses a lens or a set of lenses to enlarge an object using only angular amplification, which gives the viewer a vertical virtual image. The use of a single convex lens or group of lenses can be found in simple devices such as magnifying glass, magnifiers and eyepieces for telescopes and professional laboratory microscopes.
Combined
This type of microscope uses one of the lenses (usually the third) next to the object to collect light around it. It focuses the real image inside the microscope. Then it is enlarged using a second lens or group of lenses (called an eyepiece), which gives the viewer the opportunity to see an inverted virtual version of the object. Using a combination of lens / eyepiece can significantly increase it. Professional biological microscopes of this kind often have interchangeable lenses that allow the user to quickly adjust magnification. The combination microscope also provides more advanced lighting settings, such as phase contrast.
Stereo
A stereo, stereoscopic or dissecting microscope is a variant of an optical microscope designed for observation at a low magnification of a sample, usually using light reflected from the surface of the object rather than transmitted through it. The device uses 2 separate optical paths with two lenses and eyepieces to provide slightly different viewing angles in the left and right eyes.
This arrangement provides three-dimensional visualization of the test sample. Stereomicroscopy covers macro photography for recording and studying solid samples with complex surface topography, where a three-dimensional representation is required for analysis of parts.
A stereomicroscope is often used to study the surfaces of solid samples or to carry out close work, such as dissection, microsurgery, watchmaking, manufacturing of printed circuit boards, as well as examining the surface of cracks, both in fractography and in forensic technology. Thus, they are widely used in the manufacturing industry or for the production, determination of the composition of raw materials and quality control. Stereomicroscopes are important tools in entomology.
A stereo microscope should not be confused with a composite analog equipped with dual eyepieces and a binoviver. In such a professional microscope, both eyes see the same image, and two eyepieces serve to provide greater viewing comfort. However, the image in such a device is no different from the visualization obtained using one monocular apparatus.
Comparative
A comparative microscope is a device used for side-by-side analysis. It consists of two microscopes connected by an optical bridge, as a result of which a window with a divided view opens, allowing you to simultaneously view two separate objects. This allows the observer not to rely on memory when comparing two objects under a conventional device. Such devices are found among professional medical microscopes.
An inverted microscope (inverted) is an apparatus with a light source and a capacitor at the top, above the "stage" located below, that is, samples are examined through the bottom of the laboratory container. It was invented in 1850 by J. Lawrence Smith, a professor at the University of Tulan (then it was called Louisiana College of Medicine).
Intermediate
An intermediate professional microscope is a tool for measuring in a horizontal plane with a resolution of usually about 0.01 mm. The accuracy is such that higher quality instruments have a measuring scale made by Invar to avoid incorrect reading due to thermal effects.
The device consists of a microscope mounted on two rails attached to a very rigid base. The position of the microscope can be changed significantly, by sliding along the rails, or minimally by turning the screw. The eyepiece is equipped with accurate crosshairs to fix the optimal position, which is then read from the vernier scale.
Some instruments, such as the English professional microscopes created in the 1960s, are also measured vertically. The purpose of the microscope is to target control marks with much greater accuracy than is possible with the naked eye. It is used in laboratories to measure the refractive index of liquids using geometric concepts of radiation optics.
It is also used to measure very short distances, such as the diameter of a capillary tube. This mechanical tool is now largely replaced by electronic and optical measuring devices, which are more accurate and cost significantly less to manufacture.
For travel (portable)
The travel microscope consists of a cast iron base with a Vee-top surface finish and is equipped with three adjusting screws. A metal trolley attached to a spring-loaded rod slides with an attached vernier and reading lens along an inlaid strip of a metal scale. The latter is divided into half a millimeter. All adjustments are made with a micrometer screw for accurate reading.
The microscope tube consists of 10x eyepieces and 15mm or 50mm or 75mm targets. A microscope with a mounting gear is mounted on a vertical slide, which also works with the attached vernier on a vertical scale.
The device is free to rotate in a vertical plane. The vertical guide beam is connected to the horizontal carriage of the microscope. For holding objects, a horizontal stage is provided at the base, made of a monolithic milk sheet (polycarbonate).
Petrographic
A petrographic microscope is a type of optics that is used in petrology and optical mineralogy to determine rocks and minerals in thin sections. The microscope is used in petrography, a branch of petrology that focuses on detailed rock descriptions. The method is called “polarized light microscopy” (PLM).
Depending on the required level of observation, petrological microscopes are produced from conventional field devices with similar basic capabilities. Widespread is the use of this professional soldering microscope.
Phase Contrast Microscopy
It is an optical microscopy method that converts phase shifts in light passing through a transparent sample to changes in image brightness. The phase shifts themselves are invisible, but become visible when they are shown as a change in brightness.
This process is often carried out using professional mounting microscopes. When light waves cross a space other than vacuum, interaction with the medium leads to a change in the amplitude and phase of the wave depending on the properties of the medium. Changes in the amplitude (brightness) occur due to scattering and absorption of light, which often depends on the wavelength and can lead to the appearance of colors. Photographic equipment and the human eye are sensitive only to a change in amplitude. Thus, without special devices, phase changes are invisible. However, such studies often contain important information.
Phase contrast microscopy is especially important in biology. It shows many cellular structures that are not visible with a simpler bright field microscope, as shown in the figure. These structures were previously visible to microscopists by staining, but this required additional preparation, which led to the destruction of cells.
A phase contrast microscope has allowed biologists to examine living cells and how they proliferate through their division. After its invention in the early 1930s, phase contrast microscopy proved to be such an advance in science that its inventor Fritz Zernike was awarded the Nobel Prize in Physics in 1953.
Fluorescent
A fluorescence microscope is an optical apparatus that uses fluorescence and phosphorescence instead or in addition to scattering, reflection, and attenuation or absorption to study the properties of organic or inorganic substances.
This type of optics applies to any microscope that uses fluorescence to generate an image, whether it is a simpler setup similar to an epifluorescence device, or a more sophisticated design, such as confocal, that uses optical separation for better resolution of the fluorescence image. These devices are often used as a replacement for professional digital microscopes.