MICROSCOPE

From Big Medical Encyclopedia

MICROSCOPE — the optical device for obtaining the enlarged images of objects or details of their structure, not visible with the naked eye; is among the most widespread devices used in biology and medicine.

The historical information

Ability of systems from two lenses to enlarge the image of objects was known to the masters producing points (see). Opticians-handicraftsmen of the Netherlands and Sowing knew about such properties of semi-spherical and convexo-plane lenses. Italy in 16 century. There are data that approximately in 1590 the M device was constructed by Z. Jansen in the Netherlands.

At first there were» simple M. consisting of one lens (see. Magnifying glass ), and then more difficult M. having except a lens, and an eyepiece were designed.

Bystry distribution and M.'s improvement began after G. Galilei, improving the telescope designed by it, began to use it as a peculiar M (1609 — 1610), changing distance between a lens and an eyepiece.

Later, in 1624, having achieved production of more short-focus lenses, G. Galilei considerably reduced dimensions of the microscope.

In 1625 the member Roman «To academy sharp-sighted» («Academia dei lincei») I. Faber offered the term «microscope».

The first progress connected using M. in scientific biol, researches was reached by R. Hooke, to-ry the first described a plant cell (apprx. 1665).

A. Levenguk by means of M. found and sketched spermatozoa, various protozoa, a detail of a structure of a bone tissue (1673 — 1677).

In 1668 B]. Divini, having attached a field lens to an eyepiece, created an eyepiece of modern type; in 1673 Gavely entered a micrometer screw, and Gertel suggested to place a mirror under a stage of microscope. Thus, M. began to mount from those main details, to-rye are a part modern biol. M.

At the beginning of 18 century M. appeared in Russia; here Z. Euler for the first time developed methods of calculation of optical nodes of a microscope.

In 18 and 19 centuries M. continued to be improved. In 1827 Amichi (G. Century of Amici) for the first time applied an immersion objective in M.

At the end of 18 — the beginning of 19 century the design was offered and achromatic lenses for M. are dismissed thanks to what their optical qualities considerably improved, and the increase in objects provided with such M. increased from 500 to 1000 times.

In 1850 the English optician Sorbi (N. S. of Sorby) designed the first microscope for observation of objects in the polarized light.

In 1872 — 1873. To ABBA (E. Abbe) developed the theory of formation of images of not self-shining objects which became classical in M. Works English optics of J. Sirks (1893) laid the foundation for interferential microscopy.

In 1903 Zhigmondi and H. Siedentopf created an ultramicroscope, in 1911 Sagnac (M. of Sagnac) the first dual-beam interferential M. was described, in 1935 3 dwarf Arctic birch (F. Zernicke) suggested to use a method of phase contrast for observation in M. of the transparent, poorly scattering light objects. In the middle of 20 century the supermicroscope was invented, in 1953 the Finnish physiologist A.Wilska invented anoptralny M.

The big contribution to development of problems of theoretical and applied optics, improvement of optical systems M. and the microscopic equipment were brought by M. V. Lomonosov, I. P. Kulibin, L. I. Mandelstam, D. S. Rozhdestvensky, A. A. Lebedev, S. I. Vavilov, V. P. Linnik, D. D. Maksutov, etc.

Device of a biological microscope

Fig. 1. Outward of a biological microscope: 1 — the horseshoe basis (a support, a leg, or a boot); 2 — macroscrews of a tube; 3 — a tubusoderzhatel; 4 — eyepieces; 5 — binocular adjustment; 6 — a head for fastening of the revolver with a landing nest for change of tubes; 7 — the screw of fastening of binocular adjustment; 8 — the revolver on «sled»; 9 — lenses; 10 — a subject little table; 11 — a lamb of longitudinal motion of a preparatovoditel; 12 — a lamb of the cross movement of a preparatovoditel; 13 — the aplanatic condenser of direct and side lighting; 14 — the tsentrirovochny screw of a subject little table; 15 — a screw head, the subject little table fixing an upper part; 16 — a bracket of the condenser; 17 — the microscrew of a tube; 18 — a mirror; 19 — a box with the micromechanism.

Biological M. (fig. 1) fastens on a massive support (basis) most often having the horseshoe form. The basis is supplied with a bracket, in which there is a box of the micromechanism of thin setup of a tube of M. Besides, the box of the micromechanism has a guide for a bracket of the condenser. From above the rotating centered little table is attached to a box of the micromechanism by means of a special bracket. The arc-shaped tubusoderzhatel in the lower part is supplied with the macroscrew with two lambs serving for the rough movement of a tube. An upper part of a tubusoderzhatel is supplied from below with a head for fastening of the revolver with nests for lenses, and from above — a special landing nest for fastening of replaceable tubes: binocular adjustment for visual examinations and a monocular straight observation tube for photography.

The subject little table of M. has the device for movement of the considered drug in the directions, perpendicular each other. Counting of movement of drug in this or that direction can be made on scales with the nonius with an accuracy of 0,1 mm.

Fig. 2. The elementary optical diagram of a biological microscope with the lighter: 1 — an eye of the observer; 2 — an eyepiece; 3 — the considered object (drug); 3 — the turned image of an object formed by an eyepiece virtual from which beams, passing through optical systems of an eye of the observer, create the valid image of an object on a retina of an eye; 3" — the turned and enlarged valid image of an object; 4 — a lens; 5 — the condenser concentrating a beam of light on an object, reflected from a mirror; 6 — an aperture diaphragm; 7 — a mirror; 8 — a field diaphragm; 9 — a lens collector of the lighter; 10 — a light source; 11 — a slide plate on which have the considered object; D — distance of the best vision; shooters showed a path of rays in optical system of a microscope.

Elementary optical diagram biol. The m is given in the figure 2.

Fig. 3. The aplanatic two-lens condenser of direct and side lighting with an aperture (svetosily) 1,4 (A) and the replaceable one-lens condenser with an aperture of 0,4 (B): 1 — a rychazhok an iris diaphragm; 2 — the rotating branch pipe of the condenser; 3 — lenses in a metal frame; 4 — the rotating platform an iris diaphragm; 5 — the screw of shift an iris diaphragm for receiving slanting lighting; 6 — the light filter in a frame.

The rays of light reflected by a mirror gather the condenser. The condenser (fig. 3) consists of several lenses which are built in in the metal frame fixed by the screw in a sleeve of a bracket of the condenser and represents a high-aperture short-focus lens. Svetosila (aperture) of the condenser depends on number of lenses. Depending on methods of observation apply different types of condensers: condensers of a light and dark field; the condensers creating slanting lighting (at an angle to an optical axis M.); condensers for a research on a method of phase contrast, etc. The condenser of a dark field for a transmitted light provides illumination of drug with a hollow cone of light with a big corner; the condenser for a reflected light represents ring-shaped mirror or mirror and lens system around a lens, a so-called epikondensor.

Between a mirror and the condenser the iris diaphragm (iris diaphragm) differently called aperture since extent of its disclosure regulates an aperture of the condenser of edge is located shall be always slightly lower than an aperture of the applied lens. The diaphragm in the condenser can be located also between its separate lenses.

The basic optical element M. is the lens. It gives the valid turned and enlarged image of a body of interest. Lenses represent system of mutually centered lenses; the lens, closest to an object, is called frontal. The valid image of an object given by it suffers from a row aberrations (see), inherent to each simple lens, to-rye are eliminated with overlying correctional lenses. The majority of these lenses is very difficult: they are made of different grades of glass or even other optical materials (e.g., fluorite). Lenses on extent of correction of aberrations are divided into several groups. The simplest are achromatic lenses, their chromatic aberration is corrected for two lengths of waves and only small residual coloring of the image (aura) remains. A little smaller chromatic aberrations have semi-apochromatic, or fluorite, systems: their chromatic aberration is corrected for three lengths of waves. Planakhromatichesky and planapokhromatichesky systems eliminate curvature of the image (i.e. give a flat image field) and chromatic aberrations. Each lens is characterized by own increase, focal length, a numerical aperture and nek-ry other constants inherent to it. Own increase depends on front focal length of a lens, in size to-rogo lenses averages (focal length of 5 — 12 mm) at weak (focal length of 12 — 25 mm) and the weakest share on strong (with focal length of 1,5 — 3 mm), srednesilny (with focal length of 3,5 mm) (focal length more than 25 mm).

The numerical aperture of lenses (and condensers) is defined by the work Sin of a half of an otverstny corner, under the Crimea an object «sees» the center of a frontal lens of a lens (its «pupil») and the front of a lens of the condenser, on index of refraction of the environment concluded between these optical systems. If the air alternating with a plate of a slide plate on Krom is this Wednesday an object lies, then the numerical aperture cannot be higher than 0,95 since the index of refraction of air is equal to 1. To raise a numerical aperture, the lens is immersed (immergirut) in water, glycerin or immersion oil, i.e. on such Wednesday, index of refraction a cut higher than 1. Such lenses call immersion. Lenses M. for studying of objects in a transmitted light are counted on use of cover glasses, lenses for researches in incident light allow to consider an object without cover glass.

Fig. 4. The diagrammatic representation of an eyepiece of Huygens (I) and the path of rays in it forming the image (II): 1,9 — a field lens; 2,6 — a diaphragm; 3 — a frame of an eyepiece; 4,8 — an eye lens; 5 — the main optical axis; 7 — an output pupil; 10 — primary image; H and H' — datum planes.
Fig. 5. The diagrammatic representation of an eyepiece of Ramsden (I) and the path of rays in it forming the image (II): 1 — a frame of an eyepiece; 2,5 — a diaphragm; 3,6 — a field lens; 4,7 — an eye lens; 8 — an output pupil. The combination of field and eye lenses in Ramsden's eyepiece gives approximately the same path of rays, as well as one eye lens of an eyepiece of Huygens.

The image, a cut gives a lens, consider through the optical system called by an eyepiece. The image in an eyepiece — increased imaginary. Increase in eyepieces is usually specified on their frame, e.g. 5kh, 10kh, 15kh, etc. Eyepieces can be divided into two basic groups: normal, with a usual field of vision, and wide-angle. From various systems of eyepieces Huygens's eyepiece and Ramsden's eyepiece are the most widespread. The eyepiece of Huygens (fig. 4) which consists of two convexo-plane lenses turned by the convex party to a lens is applied during the work with achromatic and planakhromatichesky lenses at small increases. Ramsden's (fig. 5) eyepiece consists also of two convexo-plane lenses, but turned by the convex parties to each other. This eyepiece can be used also in quality magnifying glasses (see).

For correction (compensation) of residual chromatic aberrations of a lens so-called compensating oculars serve; the strongest of them give increase by 20 times.

Compensating oculars consist of a combination of the stuck together and single lenses which are picked up in such a way that their chromatic mistake to back residual chromatism of an apochromatic lens and therefore compensating residual chromatism of a lens. Photoeyepieces and projective eyepieces serve for design of the image on a film or the screen. In nek-ry cases in M. instead of eyepieces apply so-called gomala — the optical systems correcting curvature of the image of apochromatic lenses and intended for design of the image and photography. Apply to measurement of the sizes of the studied microscopic objects eyepiece micrometer (see).

Microscope lamps

can be the Light source for M. the most various lamps: filament lamps, quartz-mercury, etc.

During the work with powerful light sources from overheating or drying use heat-protective filters (the all-glass or filled with liquid translucent plates) absorbing light rays of not used lengths of waves to protection of drugs (e.g., beams of the long-wave site of a range) and an invisible heat. At a research of drug in a transmitted light the light source is located under an object, at a research in a reflected light — over an object or sideways from it. In nek-ry, hl. obr. research, M., e.g. MBI-6, MBI-15, etc., special lighters are a part of a design of M. V other cases the lighters of various brands who are let out by the industry apply. From them the transformers stabilizing tension given on a lamp, and rheostats for regulation of heat of a lamp have Nek-rye.

The simplest on the device is the lighter of OS-14. It is applied at observation of microobjects in a transmitted light in the light field. The lighter of OI-19 has more intensive light source and is used for observations in light and dark fields, method of phase contrast and so forth, and also for microphotography in the light field. The lighter of OI-25 is intended for observations in a transmitted light. It is established directly under the condenser instead of a mirror. This lighter often use during the work with portable models M. The lighter of OI-9M apply hl. obr. during the work in a transmitted light with polarizing M.; the lighter of OI-24 use during the work with biological and polarizing M. It is intended for photography of microobjects and has a set of light filters. The luminescent lighter of the SI-18 apply to work with biol., luminescent and other M. In it the mercury-quartz lamp allowing to work with the light of the UF-part of a range as which is passing, and reflected is a light source.

The optical scheme and the principle of action of a microscope

Creation of the image in M. can be explained from the point of view of geometrical optics. Rays of light from a light source through a mirror and the condenser get on an object. The lens builds the valid image of an object. This image is considered through an eyepiece. Total magnification of M. (D) is defined as performing scalingup of a lens (β) on angular increase in an eyepiece ( ok ): = β*Г ok  ; β = Δ/f' about , where Δ — distance between back focus of a lens and front focus of an eyepiece, a f' about — focal length of a lens. Increase in an eyepiece of ok = 250/f' ok , where 250 — distance from an eye to the image in mm, f' ok — focal length of an eyepiece. Increase in lenses usually makes from 6,3 to 100, and eyepieces — from 7 to 15. Total magnification of M. is in limits 44-1500; it can be counted by multiplication of the sizes characterizing increase in an eyepiece and lens. It is technically feasible to create M., lenses and eyepieces to-rykh will give the total magnification considerably exceeding 1500. However usually it is inexpedient. The essential contribution to creation of the image to M. is made by the phenomena of diffraction and an interference of light. Each small point of the lit object, according to Huygens's theory, itself becomes as if the center of the new light wave extending in all directions. All arising waves at the same time interfere, forming interference spectrums, at the same time there are dark and light sites (minima and maxima). According to the theory to ABBA the image in M. turns out similar to an object only if all rather intensive maxima get to a lens. The less maxima participate in creation of the image of an object, the less image is similar to an object.

Types of microscopes

biological M.'s Krom distinguish stereoscopic, contact, darkfield, phase and contrast, interferential, ultra-violet, infrared, polarizing, luminescent, x-ray, scanning, television, holographic, comparascopes and other types of M. Nek-rye from them, napr, phase and contrast and luminescent, can be created if necessary on the basis of a usual biol. M by means of the corresponding prefixes.

Stereomicroscope represents, as a matter of fact, two M. combined by a uniform design in such a way that the left and right eyes see an object under different corners. It gives the stereoscopic effect facilitating a research of many three-dimensional objects. This M. is widely applied in various spheres of medicobiological researches. It is especially necessary during the carrying out micromanipulations during observation (biol, researches, microsurgeries, etc.). Convenience of orientation in sight of M. is created by inclusion in its optical scheme of prisms, to-rye play a role of the turning systems: the image in such stereoscopic M. direct, but not turned.

Stereoscopic M. have, as a rule, small increase, no more than by 120 times. The released M. can be divided into two groups: M with two lenses (BM-56, etc.) and M. with one lens (MBS-1, MB of S-2, MBS-3, etc.). Binocular M. of BM-56 is the simplest of stereoscopic M. and consists of two independent optical systems, each of to-rykh gives the separate image.

Fig. 6. MBS-1 stereomicroscope: 1 — a mirror, 2 — the lighter, 3 — eyepieces of a nozzle, 4 — the microscrew, 5 — the macroscrew, 6 — a support, 7 — the power supply.

Stereoscopic M. works with MBS-1 in the passing and reflected light (fig. 6). Stereoscopic M. The MB of S-2 has a universal support, to-ry allows to work with objects of the big sizes. Stereoscopic M. MBS-3 differs from previous in an optical design, in a cut the spherochromatic aberration is substantially reduced, curvature of the image is corrected.

Exist also special binocular nalobny M. intended for microsurgeries (see. Microsurgery , Micrurgy ), and operative microscope (see).

Comparascopes consist of two structurally integrated usual M. with uniform ocular system. In such M. in two half of a field of vision images of two objects are visible at once that gives the chance to compare them on color, to structure, distribution of elements etc. M. of this kind apply at comparative study of any objects normal and pathologies, an intravital state and after fixing or coloring by various methods. M of comparison are used also in forensic medicine.

Contact microscope, used for intravital studying various biol, structures, differs from other M. in existence of special contact lenses, to-rye represent modified immersion objectives. To them originally pasted the lamina of glass and created direct contact with a surface of a body of interest. In 1963 A. P. Grammatin offered and calculated the lenses intended especially for contact microscopy. Focusing in contact M. is carried out by special optical system since the lens is not movably pressed to an object. In fluorescent contact M. the studied site of an object is lit with short-wave beams through a contact lens by means of the opak-illuminator with an interferential beam splitter.

Dark-field microscope, used in work on a method of a dark field (see. Dark field method ), allows to observe images of the transparent, not absorbing light objects which are not seen during the lighting by a method of the light field. Such objects often are biol. objects. In darkfield M. light from the lighter and a mirror goes to drug the special condenser, the so-called condenser of a dark field. After escaping of the condenser the main part of rays of light which did not change the direction during the passing through transparent drug forms a bunch in the form of a hollow cone, to-ry does not get to the lens which is in this cone. The image in darkfield M. is created only by a small part of the beams disseminated by microparticles of drug in this hollow cone and passed through a lens. Darkfield M. apply at mikrurgichesky operations on separate cells, during the studying of the mechanism of reparation process, registration of various condition of cellular elements, etc. By method of a dark field method it is also possible to investigate objects, the sizes to-rykh much less resolving power of light M. (see. Ultramicroscope ).

Phase-contrast microscope and its version — anoptralny M. serve for obtaining images of the transparent and colourless objects which are not seen at observation by a method of the light field. Usually these objects cannot be painted since coloring perniciously affects their structure, localization of chemical connections in cellular organellas, etc. (see. Phase-contrast microscopy ). This method is widely applied in microbiology. In clinical diagnostic laboratories it is used for a research of urine, unstable fabrics (e.g., at diagnosis of malignant tumors), nek-ry fixed gistol. drugs (cm. Histologic methods of a research).

Fig. 7. The optical scheme of the phase-contrast microscope with the lighter: 1 — the lighter; 2 — an aperture diaphragm; 3 — the condenser; 4 — a body of interest; 4' — the image of a body of interest; 5 — a lens; 6 — a phase plate on which surface there is a ring ledge or a ring flute, a so-called phase ring (continuous shooters showed the course of usual beams, dotted — blinded).

In phase and contrast M. (fig. 7) in front focus of the condenser establish an aperture diaphragm, an opening the cut has the form of a ring. The image constructed by it is formed near back focus of a lens, and in the same place establish a phase plate. It can be established and out of focus a lens (often phase ring is applied directly on a surface of one of lenses of a lens), but rays of light from the lighter, passing through an object, shall pass completely through a phase ring, a cut considerably weakens them and changes their phase to a quarter of wavelength. Beams, even a little rejected (disseminated) in drug, do not get to a phase ring and do not undergo shift of a phase. Taking into account phase shift of rays of light in material of drug the difference of phases between the rejected and not rejected beams amplifies; as a result of an interference of light in the plane of the image beams strengthen or weaken each other, giving the contrast image of structure of drug.

The industry releases various phase and contrast devices to M. The phase and contrast KF-4 device consists of the condenser and a set of lenses. It can be applied with biol., polarizing, luminescent and other M. The phase and contrast KF-5 device differs from KF-4 in the fact that phase plates on its lenses are put in the form of two rings, picture contrast is also slightly higher. The phase and contrast MFA-2 device differs from KF-4 in the size of phase rings and way of their drawing.

Anoptralny The m is phase and contrast M.'s kind and allows to investigate low-contrast live objects (protozoa, bacteria, viruses), but gives more contrast image, than the ordinary phase-contrast microscope. Undesirable at anoptralny M.'s use it is possible to consider emergence in nek-ry cases of auras around the image of objects. The industry the set for anoptralny microscopy of KAF-2, etc. is issued.

Interference microscope fazovokontrastny M. is intended for the solution of the same tasks, as, however between them there are also essential distinctions. In interferential M. it is possible to observe sites of objects not only with big, but also with small gradients of index of refraction or thickness, i.e. it is possible to study details of transparent objects irrespective of their form and the sizes, and not just their contours, as in phase and contrast M.

Fig. 8. Schematic diagram of one of ways of implementation of interferential contrast: 1 — the condenser; 2 — a diaphragm; 3 — an object; 4 — a lens; 5 — the compensator. Shooters showed the direction of the course of a light ray, and and and’ — birefringent plates, the first of them splits an initial light ray on two beams, and the second connects them. One of beams, passing through an object 3, is late on a phase (gets a difference of the course in comparison with the second beam), the size of this delay is measured by the compensator 5.

The principle which is the cornerstone of interferential M.'s design consists that each beam entering M. forks: one of the received beams goes through an observed particle of an object, and another — by it on the same or additional optical branch of M. (fig. 8). In an ocular part of such M. both beams connect again and interfere among themselves.

Fig. 9. The microphoto of an erythrocyte of the person in monochromatic light with the wavelength of 0,546 microns. The bend of an interference band reproduces thickness of an erythrocyte in scale.

Interferential M. is suitable for studying of living and unstable tissues, it allows to perform measurements by means of various devices, on the basis to-rykh it is possible to calculate, e.g., the mass of nonvolatile solid of vegetable: or a zooblast, concentration, the sizes of an object, content of proteins in the live and fixed objects, etc. (fig. 9).

The industry releases a large number of various interferential M. intended for biol., medical, metallurgical and other surveys. Interferential biol, the microscope of MBIN-4 intended for a research of samples in a transmitted light by an interferential method can be an example. It allows to measure also differences of the course - beams, arising at their passing through various sites of an object.

The method of interferential contrast is often combined with other microscopic techniques, e.g. with observation of objects in the polarized light, in UF-light, etc. that allows to determine, e.g., content nucleinic to - t in the general dry mass of an object.

Ultra-violet and infrared microscopes are intended for a research of objects in ultra-violet (UF) and infrared (IK) beams. These M. are supplied with cameras, fluorescent screens or electron-optical converters for fixing of the image. Resolving power of UF-microscopes is much higher, than resolving power of usual M. since their extreme permission depending on wavelength, below. Wavelength of light used in UF-microscopy, 400 — 250 nanometers whereas the wavelength of visible light of 700 — 400 nanometers. However the main advantage of UF-microscopes is that particles of many substances, transparent in visible light, strongly absorb the Uv-radiation of certain lengths of waves and, therefore, are easily distinguishable in UF-images. Characteristic absorption spectrums in the UF-spectral range a number of the substances which are contained in vegetable and zooblasts possesses. Such substances are proteins, purine bases, the pirimidinovy bases, aromatic amino acids, nek-ry lipids, vitamins, thyroxine and other biologically active compounds.

Fig. 10. Ultra-violet microscope of MUF-6: 1 — the power supply, 2 — a support, 3 — an eyepiece, 4 — a lens, 5 — a subject little table.

The research UF-microscope of MUF-6 (fig. 10) is intended for biol, researches in the passing and reflected light. He allows to carry out photography of objects, and also photographic registration of optical density and absorption spectrums of sites of a sample during the lighting by their monochromatic light.

The microphotometric ultra-violet MUF-5 installation is intended for a research biol, objects in a transmitted light. On it it is possible to make automatic recording of absorption spectrums, by means of the scanning subject little table to write down changes of optical density along the chosen direction in the necessary spectral interval, to photograph fluorescence of objects.

Fig. 11. Infrared microscope of MIK-1: 1 — the power supply, 2 — a subject little table with a preparatovoditel, 3 — the revolver with lenses, 4 — binocular adjustment, 5 — a support, 6 — the lighter.

Observation of objects by means of an infrared microscope also demands transformation of the image, invisible to an eye, in seen by its photography or by means of the electron-optical converter. The infrared microscope, e.g. MIK-1 (fig. 11), allows to study internal structure of objects, opaque to visible light (e.g., it is evil., paleontol., antropol, drugs and so forth). The infrared microscope of MIK-4 released by the industry allows to consider objects by the light of with a length of waves from 750 to 1200 nanometers, including and in the polarized light.

Polarizing microscope allows to observe bodies of interest in the polarized light and serves for studying of drugs, optical properties to-rykh are heterogeneous, i.e. so-called anisotropic objects (see. Anisotropy ). Such objects are mio-also neurofibrilla, collagenic fibers, etc. Light radiated by the lighter in such M.'s system is passed through a polarizer; polarization (see), reported at the same time to light, changes at the subsequent its passing through drug (or reflection from it). It gives the chance to allocate various elements in drug and their orientation in space that is especially important during the studying medico-biol. objects. In polarizing M. researches can be made both in passing, and in a reflected light. Polarizing M.' nodes are intended for precision quantitative measurements: eyepieces have cross hairs, micrometric scales, etc.; the rotating subject little table has a goniometric limb.

Sometimes polarizing microscopes supply with «Fedorov's little table» for installation of objects under various corners to an optical axis of the device.

In biology and medicine by means of polarizing M. control high quality of food stuffs, investigate tsitol, and gistol, drugs, structure of connecting fabric, bones and teeth.

Fig. 12. Universal MIN-8 polarizing microscope: 1 — the condenser, 2 — a subject little table, 3 — a preparatovoditel, 4 — a lens, 5 — an eyepiece, 6 — a support, 7 — the lighter, 8 — macro - and microscrews

The industry releases polarizing M. of different function. Such M.'s example is the universal MIN-8 polarizing microscope (fig. 12), to-ry has necessary equipment and additional accessories to other polarizing researches, except microscopic. The best foreign devices of this kind are universal microscopes of Ortolyuks-Paul of Leytts (Germany) and Paul of Opton.

Luminescent microscope. Luminescent M.' device is based on nek-ry physical. - chemical laws of a luminescence (see. Luminescent microscopy ). High sensitivity of luminescent M. is used in mikrobiol., immunol., tsitol, and biophysical researches.

The luminescent microscope of ML-3 released by the industry is intended for observation and photography of objects in the light of their visible fluorescence in a reflected light. The luminescent microscope of ML-2 differs from ML-3 in a possibility of observation of objects in a transmitted light. The luminescent devices used more often together with usual M. contain the lighter with a mercury lamp, a set of light filters and the so-called opak-illuminator for illumination of drugs from above. In combination with usual luminescent M. use photometric adjustment of FMEL-1, edges serves for quantitative measurement of intensity of visible fluorescence. Mikroflyuorimetr MLI-1 is applied to a research of ultra-violet and visible fluorescence in a reflected light. The device allows to perform quantitative measurements of fluorescence, photography, measurement of ranges of fluorescence, initiation of fluorescence.

X-ray microscope it is intended for a research of an object in X-ray. Focusing of beams in x-ray M. has the features: for this purpose in them the curved mirror planes are used. In x-ray M. there are also microfocal source of x-ray emission and detectors of the image: films or elekttronno-optical converters. X-ray M. of this type have a number of the shortcomings connected with structural imperfections of monocrystals and difficulties of exact processing of mirrors in view of what they were not widely used.

Projective, or «shadow», x-ray M.' principle is based on a method of a projection in the dispersing bunch of beams from a point supermicrofocal source of X-ray. Such M. have also cameras for a microobject and the chart recorder. Linear permission of M. of this type to 0,1 microns.

X-ray M. apply at a research of objects, various sites to-rykh selectively absorb X-ray, and also the objects opaque to other beams. Nek-ry models of x-ray M. are equipped with converters of x-ray emission in visible and television devices.

The scanning microscope allows to carry out consecutive survey of an object in each point or its images the photo-electric converter with measurement of intensity of the light which passed through an object or reflected from it. Scanning of an object comes down to consecutive measurement of coefficient of a transmission or reflection of rays of light from an object in each its point and to its transformation to an electric signal. The type of characteristics of the microstructures received as a result of processing of video signals is defined algorithms (see), entered into the corresponding computers; thus, the scanning M. represents a combination actually of M. and the information scanning system. It is a component of a design of analyzers and counters of particles, the television M. scanning and the integrating microphotometers etc. The scanning M. use in microbiology, cytology, genetics, histology, physiology and other fields of biology and medicine.

Use of the scanning M. or designs is perspective, to-rykh they are a part, in the diagnostic purposes, for studying of a structure and structure of fabrics, including and blood, identification in them age and patol, changes, detection of atypical cells in cuts of fabrics, etc. In experimental medicine the scanning M. apply for the purpose of control of growth and development of fabrics and cells in cultures, etc.

The industry releases the scanners executed in the form of nozzles to a light microscope.

Systems of scanning can be television and mechanical. Television apply generally to the analysis of geometrical and statistical characteristics and classification of microobjects. Mechanical are more universal and exact. They allow to work in the set spectral interval of UF-spectral ranges and are often applied to photometric measurements.

Television microscope structurally combines M. with the television equipment. Television M. work according to the scheme of a microprojection: the image of an object will be transformed to consecutive electric signals, to-rye then reproduce this image in the increased scale on the screen of a kinescope. Depending on a way of illumination of the studied object television M. subdivide into two types: M with the transferring tube and M. with the running spot.

Television M. with the transferring tube represents a simple combination of optical M. and television channel. The image given M. is projected on the screen of a kinescope. At the same time the image of signals can be observed also on the big screen even at small illumination of the object.

In television M. with the running spot use optical scanning of an object a moving ray of light.

Television devices often use in combination with fazovokontrastny M. Etim the greatest picture contrast is reached. High brightness of images in television M. allows to use them for carrying out photo and filmings of both motionless, and moving objects. Television M. can be used and as the remote device, i.e. the television receiver can be established at considerable distance from M. that it is especially important at a research of objects, the proximity to the Crimea is dangerous to the observer (e.g., radioactive). In a television microscope studying of objects in UF-and IK-beams is possible; it is used also as the television microspectrophotometer. During the use of additional electronic systems obtaining the color image is possible. On the basis of television M. automatic counters of microparticles are created (see. Avtoanalizatora ). The image in this case will be transformed by special calculating devices to a series of electric signals that allows simply and with high speed to make calculation of number of various particles in drug (erythrocytes and leukocytes in blood, bacterial clumps, particles of aerosols in air, crystals and grains in minerals, etc.), and also the whole complex of another dimensions.

The industry releases television M. of various types. Ultra-violet television M. amer. Nyyutroniks Riserch are represented by the television microspectrophotometer. It gives the three-colored image of an object corresponding to three chosen lengths of waves UF-parts of a range. Such M. allows to perform absorbing measurements.

Quantitative television M. «KTM» of English firm «Metalz Riserch» gives the chance to measure separately elements of the image with different illumination within six steps of intensity, to determine percent of the space occupied nek-dig a component of structure, to define a median number of particles for calculation of their average size, to estimate particle distribution on groups of fineness.

Holographic microscope serves as a hologram technique, i.e. the method of obtaining the volume image of an object based on an interference of waves for creation of images of objects (see. Holography ). The hologram allows to receive the image, a cut is result of registration not only amplitudes (as in the photo), but also phases of the light waves disseminated by an object. In holographic M. the laser beam is a source of waves (see. Laser ). During the use of pulse laser sources obtaining holograms of moving objects is possible. The constructive combination of holographic devices to usual M. allows to have an object vertically that is necessary at a research, e.g., of cellular suspensions. The hologram turns out from the image created by a lens. The recovered hologram reproduces the image, a cut observe through an eyepiece of M. Use of a hologram technique is perspective for studying of transparent (phase) objects; it can also be used for obtaining images of the microobjects containing slowly moving areas in a static environment (blood circulation, absorption of air traps in capillaries etc.). Holographic M. found application in a krioskopiya for studying of various cells normal and during the freezing (e.g., overseeing by processes of intracellular crystallization). In holographic M. obtaining permission apprx. 1 micron, and also black-and-white and color holograms is possible.

Holographic devices find more and more broad application as autoanalyzers of microparticles. Recognition of microparticles with use of this method accelerates in tens of thousands of times. Search of an object is conducted at the same time according to all hologram. For management of work and processing of results holographic installations connect to the COMPUTER.

See also Microscopic methods of a research .



Bibliography: Lordly I. Ya., Polyakov N. I. and Yakubenas V. A. Contact microscopy, M., 1976, bibliogr.; Bernstein A. S., Dzhokhad-z of e Sh. P. and Perova N. I. Photo-electric measuring microscopes, M., 1976, bibliogr.; Voronin V. V. Bases of the theory of a microscope, Tbilisi, 1965; M and y with t r about in L. E. Devices and tools of historical value, Microscopes, M., 1974; The Machine analysis of microscopic objects, under the editorship of G. M. Frank, M., 1968; V. A. Sirs and And N the Dr. of e e in L. N. Optik of microscopes, L., 1976, bibliogr.: The scanning equipment in a research of cell populations, cells, organoids and macromolecules, under the editorship of G. M. Frank, Pushchino - on - Oka, 1973; G.'s E.i Starlings other. Microscopes, L., 1969, bibliogr.; Fedin L. A. Microscopes, belongings to them and magnifying glasses, M., 1961, bibliogr.; Seamy side. M, etc. Some questions of use of holography in medicobiological researches, Medical tekhn., No. 1, page 30, 1976, bibliogr.


Yu. V. Agibalov, N. G. Budkovskaya, A. B. Tsypin.

Яндекс.Метрика