Microscope

Microscope

Overview
A microscope is an instrument
Laboratory equipment
Laboratory equipment refers to the various tools and equipment used by scientists working in a laboratory. These include tools such as Bunsen burners, and microscopes as well as speciality equipment such as operant conditioning chambers, spectrophotometers and calorimeters...

 used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy
Microscopy
Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye...

. Microscopic
Microscopic
The microscopic scale is the scale of size or length used to describe objects smaller than those that can easily be seen by the naked eye and which require a lens or microscope to see them clearly.-History:...

 means invisible to the eye unless aided by a microscope.

There are many types of microscopes, the most common and first to be invented is the optical microscope
Optical microscope
The optical microscope, often referred to as the "light microscope", is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest design of microscope and were possibly designed in their present compound form in the...

 which uses light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 to image the sample. Other major types of microscopes are the electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

 microscope (both the transmission electron microscope and the scanning electron microscope
Scanning electron microscope
A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...

) and the various types of scanning probe microscope.


The first microscope to be developed was the optical microscope, although the original inventor is not easy to identify.
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Encyclopedia
A microscope is an instrument
Laboratory equipment
Laboratory equipment refers to the various tools and equipment used by scientists working in a laboratory. These include tools such as Bunsen burners, and microscopes as well as speciality equipment such as operant conditioning chambers, spectrophotometers and calorimeters...

 used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy
Microscopy
Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye...

. Microscopic
Microscopic
The microscopic scale is the scale of size or length used to describe objects smaller than those that can easily be seen by the naked eye and which require a lens or microscope to see them clearly.-History:...

 means invisible to the eye unless aided by a microscope.

There are many types of microscopes, the most common and first to be invented is the optical microscope
Optical microscope
The optical microscope, often referred to as the "light microscope", is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest design of microscope and were possibly designed in their present compound form in the...

 which uses light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 to image the sample. Other major types of microscopes are the electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

 microscope (both the transmission electron microscope and the scanning electron microscope
Scanning electron microscope
A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...

) and the various types of scanning probe microscope.

History



The first microscope to be developed was the optical microscope, although the original inventor is not easy to identify. An early microscope was made in 1590 in Middelburg
Middelburg
Middelburg is a municipality and a city in the south-western Netherlands and the capital of the province of Zeeland. It is situated in the Midden-Zeeland region. It has a population of about 48,000.- History of Middelburg :...

, Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

. Two eyeglass
Glasses
Glasses, also known as eyeglasses , spectacles or simply specs , are frames bearing lenses worn in front of the eyes. They are normally used for vision correction or eye protection. Safety glasses are a kind of eye protection against flying debris or against visible and near visible light or...

 makers are variously given credit: Hans Lippershey
Hans Lippershey
Hans Lippershey , also known as Johann Lippershey or Lipperhey, was a German-Dutch lensmaker commonly associated with the invention of the telescope, although it is unclear if he was the first to build one.-Biography:...

 (who developed an early telescope
Telescope
A telescope is an instrument that aids in the observation of remote objects by collecting electromagnetic radiation . The first known practical telescopes were invented in the Netherlands at the beginning of the 1600s , using glass lenses...

) and Zacharias Janssen. Giovanni Faber
Giovanni Faber
Giovanni Faber was a German papal doctor, botanist and art collector, originally from Bamberg in Bavaria, who lived in Rome from 1598. He was curator of the Vatican botanical garden, a member and the secretary of the Accademia dei Lincei. He acted throughout his career as a political broker...

 coined the name microscope for Galileo Galilei
Galileo Galilei
Galileo Galilei , was an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations and support for Copernicanism...

's compound microscope in 1625 (Galileo had called it the "occhiolino" or "little eye").

The rise of modern light microscopy



The first detailed account of the interior construction of living tissue based on the use of a microscope did not appear until 1644, in Giambattista Odierna's L'occhio della mosca, or The Fly's Eye.

It was not until the 1660s and 1670s that the microscope was used extensively for research in Italy, Holland and England. Marcelo Malpighi in Italy began the analysis of biological structures beginning with the lungs. Robert Hooke
Robert Hooke
Robert Hooke FRS was an English natural philosopher, architect and polymath.His adult life comprised three distinct periods: as a scientific inquirer lacking money; achieving great wealth and standing through his reputation for hard work and scrupulous honesty following the great fire of 1666, but...

's Micrographia
Micrographia
Micrographia is a historic book by Robert Hooke, detailing the then thirty year-old Hooke's observations through various lenses. Published in September 1665, the first major publication of the Royal Society, it was the first scientific best-seller, inspiring a wide public interest in the new...

had a huge impact, largely because of its impressive illustrations. The greatest contribution came from Antoni van Leeuwenhoek who discovered red blood cells and spermatozoa and helped popularise microscopy as a technique. On 9 October 1676, Leeuwenhoek reported the discovery of micro-organisms.

In 1893 August Köhler
August Köhler
August Karl Johann Valentin Köhler was a German professor and early staff member of Carl Zeiss AG in Jena, Germany. He is best known for his development of the microscopy technique of Köhler illumination, an important principle in optimizing microscopic resolution power by evenly illuminating the...

 developed a key technique for sample illumination, Köhler illumination
Köhler illumination
Köhler illumination is a method of specimen illumination used for transmitted and reflected light optical microscopy. Köhler illumination acts to generate an extremely even illumination of the sample and ensures that an image of the illumination source is not visible in the resulting image...

, which is central to modern light microscopy. This method of sample illumination gives rise to extremely even lighting and overcomes many limitations of older techniques of sample illumination. Further developments in sample illumination came from Fritz Zernike in 1953 and George Nomarski 1955 for their development of phase contrast and differential interference contrast illumination which allow imaging of transparent samples.

Electron microscopy


In the early 1900s a significant alternative to light microscopy was developed, using electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

s rather than light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 to generate the image. Ernst Ruska
Ernst Ruska
Ernst August Friedrich Ruska was a German physicist who won the Nobel Prize in Physics in 1986 for his work in electron optics, including the design of the first electron microscope.Ruska was born in Heidelberg...

 started development of the first electron microscope in 1931 which was the transmission electron microscope (TEM). The transmission electron microscope works on the same principle as an optical microscope but uses electrons in the place of light and electromagnets in the place of glass lenses. Use of electrons instead of light allows a much higher resolution.

Development of the transmission electron microscope was quickly followed in 1935 by the development of the scanning electron microscope
Scanning electron microscope
A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...

 by Max Knoll
Max Knoll
Max Knoll was a German electrical engineer.Knoll was born in Wiesbaden and studied in Munich and at the Technical University of Berlin, where he obtained his doctorate in the Institute for High Voltage Technology...

.

Electron microscopes quickly became popular following the Second World War. Ernst Ruska, working at Siemens
Siemens
Siemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...

 developed the first commercial transmission electron microscope and major scientific conferences on electron microscopy started being held in the 1950s. In 1965 the first commercial scanning electron microscope was developed by Professor Sir Charles Oatley
Charles Oatley
Sir Charles William Oatley OBE, FRS FREng was Professor of Electrical Engineering, University of Cambridge, 1960–1971, and developer of one of the first commercial scanning electron microscopes....

 and his postgraduate student Gary Stewart and marketed by the Cambridge Instrument Company as the "Stereoscan".

Scanning probe microscopy



The 1980s saw the development of the first scanning probe microscopes. The first was the scanning tunneling microscope
Scanning tunneling microscope
A scanning tunneling microscope is an instrument for imaging surfaces at the atomic level. Its development in 1981 earned its inventors, Gerd Binnig and Heinrich Rohrer , the Nobel Prize in Physics in 1986. For an STM, good resolution is considered to be 0.1 nm lateral resolution and...

 in 1981, developed by Gerd Binnig and Heinrich Rohrer. This was closely followed in 1986 with Gerd Binnig, Quate, and Gerber's invention of the atomic force microscope
Atomic force microscope
Atomic force microscopy or scanning force microscopy is a very high-resolution type of scanning probe microscopy, with demonstrated resolution on the order of fractions of a nanometer, more than 1000 times better than the optical diffraction limit...

.

Fluorescence and light microscopy



The most recent developments in light microscope largely centre on the rise of fluorescence microscopy
Fluorescence microscope
A fluorescence microscope is an optical microscope used to study properties of organic or inorganic substances using the phenomena of fluorescence and phosphorescence instead of, or in addition to, reflection and absorption...

 in biology
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...

. During the last decades of the 20th century, particularly in the post-genomic
Genome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....

 era, many techniques for fluorescent labeling of cellular
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....

 structures were developed. The main groups of techniques are small chemical staining of cellular structures, for example DAPI
DAPI
DAPI or 4',6-diamidino-2-phenylindole is a fluorescent stain that binds strongly to A-T rich regions in DNA. It is used extensively in fluorescence microscopy...

 to label DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...

, use of antibodies conjugated to fluorescent reporters, see
immunofluorescence
Immunofluorescence
Immunofluorescence is a technique used for light microscopy with a fluorescence microscope and is used primarily on biological samples. This technique uses the specificity of antibodies to their antigen to target fluorescent dyes to specific biomolecule targets within a cell, and therefore allows...

, and fluorescent proteins, such as green fluorescent protein
Green fluorescent protein
The green fluorescent protein is a protein composed of 238 amino acid residues that exhibits bright green fluorescence when exposed to blue light. Although many other marine organisms have similar green fluorescent proteins, GFP traditionally refers to the protein first isolated from the...

. These techniques use these different fluorophores for analysis of cell structure at a molecular level in both live and fixed samples.

The rise of fluorescence microscopy drove the development of a major modern microscope design, the confocal microscope. The principle was patented in 1957 by Marvin Minsky
Marvin Minsky
Marvin Lee Minsky is an American cognitive scientist in the field of artificial intelligence , co-founder of Massachusetts Institute of Technology's AI laboratory, and author of several texts on AI and philosophy.-Biography:...

, although laser
Laser
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...

 technology limited practical application of the technique. It was not until 1978 when Thomas
Thomas Cremer
Thomas Cremer , is a German professor of human genetics and anthropology with a main research focus on molecular cytogenetics and 3D/4D analyses of nuclear structure studied by confocal microscopy and live cell imaging...

 and Christoph Cremer
Christoph Cremer
Christoph Cremer is a German physicist and professor at the Ruprecht-Karls-University Heidelberg, who has successfully overcome the conventional limit of resolution that applies to light based investigations by a range of different methods Christoph Cremer (born in Freiburg im Breisgau, Germany)...

 developed the first practical confocal laser scanning microscope and the technique rapidly gained popularity through the 1980s.
Much current research (in the early 21st century) on optical microscope techniques is focused on development of superresolution analysis of fluorescently labeled samples. Structured illumination can improve resolution by around two to four times and techniques like stimulated Emission Depletion microscopy are approaching the resolution of electron microscopes.

Types



Microscopes can be separated into several different classes. One grouping is based on what interacts with the sample to generate the image, i.e., light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...

 (optical microscopes), electrons (electron microscopes) or a probe (scanning probe microscopes). Alternatively microscopes can be classed on whether they analyse the sample via a scanning point (confocal optical microscopes, scanning electron microscopes and scanning probe microscopes) or analyze the sample all at once (wide field optical microscope and transmission electron microscopes).

The wide field optical microscope and transmission electron microscope use the theory of lenses (optics
Optics
Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light...

 for light microscopes and electromagnet
Electromagnet
An electromagnet is a type of magnet in which the magnetic field is produced by the flow of electric current. The magnetic field disappears when the current is turned off...

 lenses for electron microscopes) in order to magnify the image generated by the passage of a wave
Wave
In physics, a wave is a disturbance that travels through space and time, accompanied by the transfer of energy.Waves travel and the wave motion transfers energy from one point to another, often with no permanent displacement of the particles of the medium—that is, with little or no associated mass...

 through the sample, or reflected by the sample. The waves used are electromagnetic (in optical microscope
Optical microscope
The optical microscope, often referred to as the "light microscope", is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest design of microscope and were possibly designed in their present compound form in the...

s) or electron
Electron
The electron is a subatomic particle with a negative elementary electric charge. It has no known components or substructure; in other words, it is generally thought to be an elementary particle. An electron has a mass that is approximately 1/1836 that of the proton...

 beams (in electron microscopes). Resolution
Optical resolution
Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.An imaging system may have many individual components including a lens and recording and display components...

 in these microscopes is limited by the wavelength of the radiation used to image the sample, shorter wavelengths allow a higher resolution.

Scanning optical and electron microscopes, like the confocal microscope and scanning electron microscope, use lenses to focus a spot of light/electrons onto the sample then analyze the reflected and/or transmitted waves. The point is then scanned over the sample to analyze a rectangular region. Magnification of the image is achieved by displaying the data from scanning a small sample area on a large screen. These microscopes have the same resolution limit as wide field optical and electron microscopes.

Scanning probe microscopes also analyze a single point in the sample and then scan the probe over a rectangular sample region to build up an image. As these microscopes do not use electromagnetic or electron radiation for imaging they are not subject to the same resolution limit as the optical and electron microscopes described above.

Optical



The most common type of microscope—and the first invented—is the optical microscope
Optical microscope
The optical microscope, often referred to as the "light microscope", is a type of microscope which uses visible light and a system of lenses to magnify images of small samples. Optical microscopes are the oldest design of microscope and were possibly designed in their present compound form in the...

. This is an optical
Optics
Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light...

 instrument
Measuring instrument
In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item...

 containing one or more lenses
Lens (optics)
A lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element...

 producing an enlarged image of a sample placed in the focal plane. Optical microscopes have refractive
Refraction
Refraction is the change in direction of a wave due to a change in its speed. It is essentially a surface phenomenon . The phenomenon is mainly in governance to the law of conservation of energy. The proper explanation would be that due to change of medium, the phase velocity of the wave is changed...

 glass and occasionally of plastic or quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

, to focus light into the eye or another light detector. Mirror-based optical microscopes operate in the same manner. Typical magnification of a light microscope, assuming visible range light, is up to 1500x with a theoretical resolution limit of around 0.2 micrometres or 200 nanometres. Specialized techniques (e.g., scanning confocal microscopy
Confocal laser scanning microscopy
Confocal laser scanning microscopy is a technique for obtaining high-resolution optical images with depth selectivity. The key feature of confocal microscopy is its ability to acquire in-focus images from selected depths, a process known as optical sectioning...

, Vertico SMI
Vertico SMI
Vertico-SMI is currently the fastest light microscope for the 3D analysis of complete cells in the nanometer range. It is based on two technologies developed in 1996, SMI and SPDM...

) may exceed this magnification but the resolution is diffraction
Diffraction
Diffraction refers to various phenomena which occur when a wave encounters an obstacle. Italian scientist Francesco Maria Grimaldi coined the word "diffraction" and was the first to record accurate observations of the phenomenon in 1665...

 limited. The use of shorter wavelengths of light, such as the ultraviolet, is one way to improve the spatial resolution of the optical microscope, as are devices such as the near-field scanning optical microscope
Near-field scanning optical microscope
Near-field scanning optical microscopy is a microscopic technique for nanostructure investigation that breaks the far field resolution limit by exploiting the properties of evanescent waves. This is done by placing the detector very close to the specimen surface...

.
Sarfus
Sarfus
Sarfus is an optical quantitative imaging technique based on the association of:*an upright or inverted optical microscope in crossed polarization configuration and*specific supporting plates - called surfs - on which the sample to observe is deposited....

, a recent optical technique increases the sensitivity of standard optical microscope to a point it becomes possible to directly visualize nanometric films (down to 0.3 nanometre) and isolated nano-objects (down to 2 nm-diameter). The technique is based on the use of non-reflecting substrates for cross-polarized reflected light microscopy.
Ultraviolet
Ultraviolet
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than X-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...

 light enables the resolution of microscopic features, as well as to image samples that are transparent to the eye. Near infrared light images circuitry embedded in bonded silicon devices, as silicon is transparent in this region. Many wavelengths of light, ranging from the ultraviolet to the visible are used to excite fluorescence
Fluorescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength. It is a form of luminescence. In most cases, emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation...

 emission from objects for viewing by eye or with sensitive cameras.

Phase contrast microscopy is an optical microscopy illumination
Lighting
Lighting or illumination is the deliberate application of light to achieve some practical or aesthetic effect. Lighting includes the use of both artificial light sources such as lamps and light fixtures, as well as natural illumination by capturing daylight...

 technique in which small phase shifts in the light passing through a transparent specimen are converted into amplitude
Amplitude
Amplitude is the magnitude of change in the oscillating variable with each oscillation within an oscillating system. For example, sound waves in air are oscillations in atmospheric pressure and their amplitudes are proportional to the change in pressure during one oscillation...

 or contrast
Contrast (vision)
Contrast is the difference in visual properties that makes an object distinguishable from other objects and the background. In visual perception of the real world, contrast is determined by the difference in the color and brightness of the object and other objects within the same field of view...

 changes in the image.
A phase contrast microscope does not require staining to view the slide. This microscope made it possible to study the cell cycle
Cell cycle
The cell cycle, or cell-division cycle, is the series of events that takes place in a cell leading to its division and duplication . In cells without a nucleus , the cell cycle occurs via a process termed binary fission...

.

The traditional optical microscope has recently been modified into a digital microscope
Digital microscope
A digital microscope is a variation of a traditional optical microscope that uses optics and a charge-coupled device camera to output a digital image to a monitor, sometimes by means of software running on a computer. A digital microscope differs from an optical microscope in that there is no...

, where, instead of directly viewing the object, a charge-coupled device
Charge-coupled device
A charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...

 (CCD) is used to record the image, which is then displayed on a computer monitor.

Electron



Three major variants of electron microscopes exist:
  • Scanning electron microscope
    Scanning electron microscope
    A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...

     (SEM
    Scanning electron microscope
    A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...

    ): looks at the surface of bulk objects by scanning the surface with a fine electron beam. See also environmental scanning electron microscope (ESEM).
  • Transmission electron microscope (TEM
    Transmission electron microscopy
    Transmission electron microscopy is a microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it passes through...

    ): passes electrons through the sample, analogous to basic optical microscopy
    Bright field microscopy
    Bright field microscopy is the simplest of all the optical microscopy illumination techniques. Sample illumination is transmitted white light and contrast in the sample is caused by absorbance of some of the transmitted light in dense areas of the sample...

    . This requires careful sample preparation, since electrons are scattered so strongly by most materials.This is a scientific device that allows people to see objects that could normally not be seen by the naked or unaided eye.

Scanning probe

  • AFM, atomic force microscopy
  • BEEM, ballistic electron emission microscopy
    Ballistic electron emission microscopy
    Ballistic electron emission microscopy or BEEM is a technique for studying ballistic electron transport through a variety of materials and material interfaces. BEEM is a three terminal scanning tunneling microscopy technique that was invented in 1988 at the Jet Propulsion Laboratory in Pasadena...

  • EFM, electrostatic force microscope
    Electrostatic force microscope
    Electrostatic force microscopy is a type of dynamic non-contact atomic force microscopy where the electrostatic force is probed. . This force arises due to the attraction or repulsion of separated charges. It is a long-ranged force and can be detected 100 nm from the sample...

  • ESTM electrochemical scanning tunneling microscope
    Electrochemical scanning tunneling microscope
    The electrochemical scanning tunneling microscope, or ESTM, was invented in 1988 by Kingo Itaya in Japan. With ESTM, the structures of surfaces and electrochemical reactions in solid-liquid interfaces can be observed at atomic or molecular scales....

  • FMM, force modulation microscopy
  • KPFM, kelvin probe force microscopy
    Kelvin probe force microscope
    Kelvin probe force microscopy , also known as surface potential microscopy, is a noncontact variant of atomic force microscopy that was invented in 1991. With KPFM, the work function of surfaces can be observed at atomic or molecular scales...

  • MFM, magnetic force microscopy
  • MRFM, magnetic resonance force microscopy
    Magnetic Resonance Force Microscopy
    Magnetic resonance force microscopy is an imaging technique that acquires magnetic resonance images at nanometer scales, and possibly at atomic scales in the future. MRFM is potentially able to observe protein structures which cannot be seen using X-ray crystallography and protein nuclear...

  • NSOM, near-field scanning optical microscopy (or SNOM, scanning near-field optical microscopy)
  • PFM, piezo force microscopy
  • PSTM, photon scanning tunneling microscopy
  • PTMS, photothermal microspectroscopy
    Photothermal microspectroscopy
    Photothermal microspectroscopy , alternatively known as photothermal temperature fluctuation , is derived from two parent instrumental techniques: infrared spectroscopy and atomic force microscopy...

    /microscopy
  • SAP, scanning atom probe
  • SCM, scanning capacitance microscopy
    Scanning capacitance microscopy
    Scanning capacitance microscopy is a variety of scanning probe microscopy in which a narrow probe electrode is held just above the surface of a sample and scanned across the sample...

  • SECM, scanning electrochemical microscopy
  • SEM, scanning electron microscopy
  • SGM, scanning gate microscopy
    Scanning gate microscopy
    Scanning gate microscopy is a scanning probe microscopy technique with an electrically conductive tip used as a movable gate that couples capacitively to the sample and probes electrical transport on the nanometer scale. Typical samples are mesoscopic devices, often based on semiconductor...

  • SICM, scanning ion-conductance microscopy
    Scanning ion-conductance microscopy
    The scanning ion-conductance microscope consists of an electrically charged glass micro- or nanopipette probe filled with electrolyte lowered toward the surface of the sample in an oppositely charged bath of electrolyte...

  • SPSM spin polarized scanning tunneling microscopy
    Spin polarized scanning tunneling microscopy
    Spin polarized scanning tunneling microscopy is a specialized application of scanning tunneling microscopy that can provide detailed information of magnetic phenomena on the single-atom scale additional to the atomic topology gained with STM...

  • SThM, scanning thermal microscopy
    Scanning thermal microscopy
    Scanning thermal microscopy is a type of scanning probe microscopy that maps the local temperature and thermal conductivity of an interface. The probe in a scanning thermal microscope is sensitive to local temperatures - providing a nanoscale thermometer...

    /annurev.matsci.29.1.505]
  • STM, scanning tunneling microscopy
  • SVM, scanning voltage microscopy
    Scanning voltage microscopy
    Scanning voltage microscopy -- sometimes also called nanopotentiometry -- is a scientific experimental technique based on atomic force microscopy. A conductive probe, usually only a few nanometers wide at the tip, is placed in full contact with an operational electronic or optoelectronic sample...

  • SHPM, scanning Hall probe microscopy
  • SSM, Scanning SQUID microscope
    Scanning SQUID microscope
    A Scanning SQUID Microscope is a sensitive near-field imaging system for the measurement of weak magnetic fields by moving a Superconducting Quantum Interference Device across an area. The microscope can map out buried current-carrying wires by measuring the magnetic fields produced by the...



Of these techniques AFM and STM are the most commonly used.

Other


Scanning acoustic microscope
Scanning acoustic microscope
A Scanning Acoustic Microscope is a device which uses focused sound to investigate, measure, or image an object . It is commonly used in failure analysis and non-destructive evaluation. It also has applications in biological and medical research...

s use sound waves to measure variations in acoustic impedance. Similar to Sonar
Sonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...

 in principle, they are used for such jobs as detecting defects in the subsurfaces of materials including those found in integrated circuits.

See also

  • Bright field microscopy
    Bright field microscopy
    Bright field microscopy is the simplest of all the optical microscopy illumination techniques. Sample illumination is transmitted white light and contrast in the sample is caused by absorbance of some of the transmitted light in dense areas of the sample...

  • Confocal microscopy
    Confocal microscopy
    Confocal microscopy is an optical imaging technique used to increase optical resolution and contrast of a micrograph by using point illumination and a spatial pinhole to eliminate out-of-focus light in specimens that are thicker than the focal plane. It enables the reconstruction of...

  • Dark field microscopy
    Dark field microscopy
    Dark field microscopy describes microscopy methods, in both light and electron microscopy, which exclude the unscattered beam from the image. As a result, the field around the specimen Dark field microscopy (dark ground microscopy) describes microscopy methods, in both light and electron...

  • Digital microscope
    Digital microscope
    A digital microscope is a variation of a traditional optical microscope that uses optics and a charge-coupled device camera to output a digital image to a monitor, sometimes by means of software running on a computer. A digital microscope differs from an optical microscope in that there is no...

  • Fluorescence interference contrast microscopy
    Fluorescence interference contrast microscopy
    Fluorescence interference contrast microscopy is a microscopic technique developed to achieve z-resolution on the nanometer scale.FLIC occurs whenever fluorescent objects are in the vicinity of a reflecting surface...

  • Fluorescence microscope
    Fluorescence microscope
    A fluorescence microscope is an optical microscope used to study properties of organic or inorganic substances using the phenomena of fluorescence and phosphorescence instead of, or in addition to, reflection and absorption...

  • Laser capture microdissection
    Laser capture microdissection
    Laser capture microdissection , also called Microdissection, Laser MicroDissection , or Laser-assisted microdissection is a method for isolating specific cells of interest from microscopic regions of tissue/cells/organisms....

  • Microscope image processing
    Microscope image processing
    Microscope image processing is a broad term that covers the use of digital image processing techniques to process, analyze and present images obtained from a microscope. Such processing is now commonplace in a number of diverse fields such as medicine, biological research, cancer research, drug...

  • Microscope slide
    Microscope slide
    A microscope slide is a thin flat piece of glass, typically 75 by 25 mm and about 1 mm thick, used to hold objects for examination under a microscope. Typically the object is placed or secured on the slide, and then both are inserted together in the microscope for viewing...

  • Microscopy
    Microscopy
    Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye...

  • Microscopy laboratory in: A Study Guide to the Science of Botany at Wikibooks
  • Phase contrast microscopy
    Phase contrast microscopy
    Phase contrast microscopy is an optical microscopy illumination technique of great importance to biologists in which small phase shifts in the light passing through a transparent specimen are converted into amplitude or contrast changes in the image.A phase contrast microscope does not require...

  • Timeline of microscope technology
    Timeline of microscope technology
    Timeline of microscope technology* 1590 - Dutch spectacle-makers Hans Jansen and his son Zacharias Jansen, claimed by later writers to have invented a compound microscope....

  • X-ray microscope
    X-ray microscope
    An X-ray microscope uses electromagnetic radiation in the soft X-ray band to produce images of very small objects.Unlike visible light, X-rays do not reflect or refract easily, and they are invisible to the human eye. Therefore the basic process of an X-ray microscope is to expose film or use a...


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