Introduction to Microscope Microscope is an optical instrument composed of one lens or several lenses, which indicates that mankind has entered the atomic age. It is mainly used to enlarge tiny objects to be visible to human naked eyes. Microscope can be divided into optical microscope and electron microscope: optical microscope was first created by Zhan Sen and his son in Holland in 1590. At present, the optical microscope can enlarge the object by 1600 times, and the lowest resolution reaches 1/2 wavelength. The length of mechanical cylinder of microscope in China is generally 160 mm, among which Levin Hooke and Dutch nationals have made great contributions to the development of microscope and microbiology.
Process microscope is one of the greatest inventions in the 20th century. Before it was invented, human's concept of the world around him was limited to what the naked eye could see, or through holding a lens.
Microscope shows a brand-new world in human vision. For the first time, people saw hundreds of new kinds of tiny animals and plants, and all the internal structures from human body to plant fibers. Microscopes also help scientists discover new species and help doctors treat diseases.
The earliest microscope was made in Holland at the end of16th century. The inventor is the Dutch optician Yas Zhan Sen or another Dutch scientist, hensley Percy. They made a simple microscope with two lenses, but they didn't make any important observations with these instruments.
Later, two people began to use microscopes in science. The first is the Italian scientist Galileo. He described the compound eyes of insects for the first time after observing them through a microscope. The second is the Dutch linen dealer Levin Hooke (1632-1723), who taught himself to grind lenses. For the first time, he described many tiny plants and animals invisible to the naked eye.
193 1 year, Ernst ruska invented an electron microscope, which completely changed biology. This enables scientists to observe objects as small as a millionth of a millimeter. 1986 won the Nobel Prize.
Microscope classification microscopes can be divided into polarizing microscope, optical microscope, electron microscope and digital microscope according to microscope principle.
Micrometer polarizer
Polarizingmicroscope is a kind of microscope used to study the so-called transparent and opaque anisotropic materials, which has important applications in geology and other science and engineering majors. Under the polarizing microscope, all substances with birefringence can be clearly distinguished. Of course, these substances can also be observed by dyeing, but some can't, and a polarizing microscope must be used. Reflective polarization microscope is an essential instrument to study and identify birefringent substances by using the polarization characteristics of light, which can be used for users to observe single polarization, orthogonal polarization and cone-shaped light.
optical microscope
Usually consists of optical part, lighting part and mechanical part. There is no doubt that the optical part is the most critical, consisting of eyepiece and objective lens. As early as 1590, glasses manufacturers in the Netherlands and Italy have made magnifying instruments similar to microscopes. There are many kinds of optical microscopes, mainly including bright-field microscope (ordinary optical microscope), dark-field microscope, fluorescence microscope, phase contrast microscope, laser scanning focusing microscope, polarizing microscope, differential interference difference microscope, inverted microscope and so on.
electron microscope
The electron microscope has similar basic structural characteristics to the optical microscope, but it has much higher magnification and resolution than the optical microscope. It uses electron flow as a new light source to image objects. Since ruska invented the first transmission electron microscope in 1938, many other types of electron microscopes have been developed besides the continuous improvement of transmission electron microscope itself. Such as scanning electron microscope, analytical electron microscope, ultra-high pressure electron microscope, etc. Combined with various electron microscope sample preparation techniques, we can study the structure of samples or the relationship between structure and function in many aspects. Microscopes are used to observe images of tiny objects. It is often used in biology, medicine and observation of tiny particles. An electron microscope can magnify an object 2 million times.
Desktop microscope, mainly refers to traditional microscope, is pure optical magnification, with high magnification and good imaging quality, but it is generally large and inconvenient to move, and is mostly used in laboratories, which is not convenient for going out or on-site detection.
Portable microscope
Portable microscope is mainly an extension of digital microscope and video microscope series developed in recent years. Different from the traditional optical amplification, hand-held microscopes are all digital amplification, and generally pursue portability, compactness, exquisiteness and portability; Moreover, some hand-held microscopes have their own screens, which can be imaged independently from the computer host, which is convenient to operate, and can also integrate some digital functions, such as supporting photography, video recording, or image comparison measurement.
Digital liquid crystal microscope was first developed and produced by Bo Company. This microscope retains the clarity of optical microscope, and integrates the powerful expansion of digital microscope, the intuitive display of video microscope and the simplicity and convenience of portable microscope.
Scanning tunneling microscope
Scanning tunneling microscope, also known as scanning tunneling microscope and tunneling scanning microscope, is an instrument that uses the tunneling effect in quantum theory to detect the surface structure of substances. It was invented in 198 1 by G Ning Bin and H Basil in the Zurich laboratory of IBM in Zurich, Switzerland, so the two inventors shared the 1986 Nobel Prize in Physics with Ernst ruska.
As a scanning probe microscope tool, scanning tunneling microscope allows scientists to observe and locate a single atom, and it has higher resolution than similar atomic force microscopes. In addition, scanning tunneling microscope (STM) can accurately manipulate atoms with probe tips at low temperature (4K), so it is not only an important measuring tool but also a processing tool in nanotechnology.
STM makes it possible for human beings to observe the arrangement of single atoms on the surface of matter and the physical and chemical properties related to the surface electronic behavior for the first time. It has great significance and broad application prospects in the research of surface science, material science, life science and other fields, and is recognized by the international scientific community as one of the top ten scientific and technological achievements in the world in the 1980s.
Development history
As early as the first century BC, people have found that when observing tiny objects through spherical transparent objects, the images can be enlarged. Later, I gradually realized that the surface energy of spherical glass magnifies the image of an object.
In 1590, ZJansen (Zhan Sen) in the Netherlands and Italian glasses manufacturers have built magnifying instruments similar to microscopes.
16 1 1 year, Kepler: The manufacturing method of compound microscope was put forward.
In 1665, robert Hooke: The origin of the word "cell" was obtained by Hooke observing micropores in cork tissue with a compound microscope.
1674, AVLeeuwenhoek (Levin Hook): protozoology's report was published, and nine years later he became the first person to discover the existence of "bacteria".
1833, Brown: Observe violets under a microscope, and then publish his detailed discussion on the nucleus.
1838, SchliedenandSchwann (Schleiden and Wang Shi): Both of them advocate the principle of cytology, and their main idea is that nucleated cells are the basic elements of all animal and plant tissues and functions.
1857, Kolliker: Mitochondria were found in muscle cells.
1876, Abbe: Analyze the diffraction effect of the image when it is imaged in the microscope, and try to design the most ideal microscope.
18
1979, Flrmming (Fleming): It was found that when an animal cell is undergoing mitosis, its chromosome activity is clearly visible.
188 1, Retziue (Ruizu): The report of animal organization has come out, which no one in the world can surpass. However, 20 years later, a group of histologists led by Cahal developed the microscopic staining observation method, which laid the foundation for the future microscopic anatomy.
1882, Koch (Kirk): Staining microbial tissues with benzene dye, from which he found cholera and mycobacterium tuberculosis. In the next 20 years, other bacteriologists, such as Kleber and Pasteur (Klebel and Pasteur), confirmed the causes of many diseases by examining the staining drugs under the microscope.
Zeiss (1886): It broke the theoretical limit of general visible light, and his invention-Abbey Type and a series of lenses opened up a new world for microscopists to interpret images.
1898, Gorky: The first microscopist to find Golgi apparatus in bacteria. He used silver nitrate to dye cells, which made a big step in the study of human cells.
1924, Lacassagne: He and his experimental partner * * * developed radiography together, that is, using radioactive polonium to explore biological specimens.
1930, lebedev: The first interference microscope was designed and matched. In addition, zernike invented the phase difference microscope in 1932, and the phase difference observer developed by them expanded the traditional optical microscope, enabling biologists to observe various details on stained living cells.
194 1 year, Coons: antibody was added with fluorescent dye to detect cell antigen.
1952, Nomarski: the optical system of interference phase difference was invented. This invention is not only patented, but also named after the inventor himself.
198 1 year, allenandinou(Allen and Ainu): The images in the principle of optical microscope have been enhanced and compared, and the development is close to perfection.
From 65438 to 0988, confocal (yoke focus) scanning microscope was widely used in the market.
Digital microscope
Digital microscope is a high-tech product that combines elite optical microscope technology, advanced photoelectric conversion technology and LCD screen technology perfectly. Therefore, we can observe the reproduction on the display from the traditional ordinary binocular to study the microscopic field, thus improving the work efficiency.