A microscope (from the Greek: μικρός, mikrós, "small" and σκοπεῖν, skopeîn, "to look" or "see") is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. The science of investigating small objects using such an instrument is called microscopy. The term microscopic means minute or very small, not visible with the eye unless aided by a microscope.
History
Microscopes trace their history back almost 1200 years with Abbas Ibn Firnas's corrective lenses,[1] and it was Ibn al-Haytham's Book of Optics — written between 1011 and 1021 — that laid the foundation for optical research on the magnifying glass. Also, a device called the reading stone by an unknown inventor (thought to be Ibn Firnas) magnified text when laid on top of reading materials.[2]
The first true microscope was made around 1595 in Middelburg, The Netherlands.[3] Three different eyeglass makers have been given credit for the invention: Hans Lippershey (who also developed the first real telescope); Hans Janssen; and his son, Zacharias. The coining of the name "microscope" has been credited to Giovanni Faber, who gave that name to Galileo Galilei's compound microscope in 1625.[4] (Galileo had called it the "occhiolino" or "little eye".)
The most common type of microscope—and the first to be invented—is the optical microscope. This is an optical instrument containing one or more lenses that produce an enlarged image of an object placed in the focal plane of the lens(es). There are, however, many other microscope designs.
The first true microscope was made around 1595 in Middelburg, The Netherlands.[3] Three different eyeglass makers have been given credit for the invention: Hans Lippershey (who also developed the first real telescope); Hans Janssen; and his son, Zacharias. The coining of the name "microscope" has been credited to Giovanni Faber, who gave that name to Galileo Galilei's compound microscope in 1625.[4] (Galileo had called it the "occhiolino" or "little eye".)
The most common type of microscope—and the first to be invented—is the optical microscope. This is an optical instrument containing one or more lenses that produce an enlarged image of an object placed in the focal plane of the lens(es). There are, however, many other microscope designs.
Types
Several types of microscops
Several types of microscopes
"Microscopes" can largely be separated into three classes: optical theory microscopes (Light microscope), electron microscopes (e.g.,TEM), and scanning probe microscopes (SPM).
Optical theory microscopes are microscopes which function through the optical theory of lenses in order to magnify the image generated by the passage of a wave through the sample. The waves used are either electromagnetic (in optical microscopes) or electron beams (in electron microscopes). The types are the Compound Light, Stereo, and the electron microscope.
[edit] Optical microscopes
Main article: Optical microscope
Optical microscopes, through their use of visible wavelengths of light, are the simplest and hence most widely used type of microscope.
Optical microscopes typically use refractive glass and occasionally of plastic or 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 nanometers. Specialized techniques (e.g., scanning confocal microscopy) may exceed this magnification but the resolution is diffraction limited. Using shorter wavelengths of light, such as the ultraviolet, is one way to improve the spatial resolution of the microscope as are techniques such as Near-field scanning optical microscope.
A stereo microscope is often used for lower-power magnification on large subjects.
Various wavelengths of light, including those beyond the visible range, are sometimes used for special purposes. Ultraviolet light is used to enable the resolution of smaller features as well as to image samples that are transparent to the eye. Near infrared light is used to image 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 emission from objects for viewing by eye or with sensitive cameras.
phase contrast microscope:Phase contrast microscopy is an optical microscopy illumination technique 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 staining to view the slide. This microscope made it possible to study the cell cycle.The Digital microscope appeared a few years ago, using optics and a charge-coupled device (CCD) camera to output a digital image to a monitor. This technology invented by Hirox offers a much higher depth of field and working distance as well as increased flexibility of inspection for large sized objects (NDT, skin, paintings) in a broad range of applications.
[edit] Electron Microscopes
Main article: Electron microscope
Three major variants of electron microscopes exist:
Scanning electron microscope (SEM): looks at the surface of bulk objects by scanning the surface with a fine electron beam and measuring reflection. May also be used for spectroscopy.
Transmission electron microscope (TEM): passes electrons completely through the sample, analogous to basic optical microscopy. 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 Tunneling Microscope (STM): is a powerful technique for viewing surfaces at the atomic level.
The SEM, TEM, STM are included in the scanning probe microscopy.
[edit] Established types of scanning probe microscopy
AFM, atomic force microscopy
Contact AFM
Non-contact AFM
Dynamic contact AFM
Tapping AFM
BEEM, ballistic electron emission microscopy
EFM, electrostatic force microscope
ESTM electrochemical scanning tunneling microscope
FMM, force modulation microscopy
KPFM, kelvin probe force microscopy
MFM, magnetic force microscopy
MRFM, magnetic resonance force microscopy
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/microscopy
SAP, scanning atom probe [5]
SECM, scanning electrochemical microscopy
SCM, scanning capacitance microscopy
SGM, scanning gate microscopy
SICM, scanning ion-conductance microscopy
SPSM spin polarized scanning tunneling microscopy
SThM, scanning thermal microscopy[2]
STM, scanning tunneling microscopy
SVM, scanning voltage microscopy
SHPM, scanning Hall probe microscopy
SSM, Scanning SQUID microscope
Of these techniques AFM and STM are the most commonly used followed by MFM and SNOM/NSOM.
[edit] Other microscopes
Scanning acoustic microscopes use sound waves to measure variations in acoustic impedance. Similar to Sonar in principle, they are used for such jobs as detecting defects in the subsurfaces of materials including those found in integrated circuits.
[edit] See also
Different microscopes
Wikimedia Commons has media related to: Microscopes
Acronyms in microscopy
Angular resolution
Bright field microscopy
Condensed Matter Physics
Confocal microscopy
Dark field microscopy
Digital microscope
Electron Microscope
Fluorescence interference contrast microscopy
Fluorescence microscope
Microscope image processing
Microscopy
Optical Microscope
Intel Play
Phase contrast microscopy
Microscope slide
Telescope
Timeline of microscope technology
X-ray microscope
Microscopy laboratory in: A Study Guide to the Science of Botany at Wikibooks
Laser capture microdissection
[edit] References
^ Ajram, K. (1992). The miracle of Islamic science. Knowledge House Publishers. pp. Appendix B. ISBN 0-911119-43-4.
^ [1] Timeline - History of Microscopes
^ Microscopes: Time Line
^ Stephen Jay Gould(2000). The Lying Stones of Marrakech, ch.2 "The Sharp-Eyed Lynx, Outfoxed by Nature". London: Jonathon Cape. ISBN 0224050443
^ Morita, Seizo. Roadmap of Scanning Probe Microscopy. 3 January 2007
Several types of microscops
Several types of microscopes
"Microscopes" can largely be separated into three classes: optical theory microscopes (Light microscope), electron microscopes (e.g.,TEM), and scanning probe microscopes (SPM).
Optical theory microscopes are microscopes which function through the optical theory of lenses in order to magnify the image generated by the passage of a wave through the sample. The waves used are either electromagnetic (in optical microscopes) or electron beams (in electron microscopes). The types are the Compound Light, Stereo, and the electron microscope.
[edit] Optical microscopes
Main article: Optical microscope
Optical microscopes, through their use of visible wavelengths of light, are the simplest and hence most widely used type of microscope.
Optical microscopes typically use refractive glass and occasionally of plastic or 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 nanometers. Specialized techniques (e.g., scanning confocal microscopy) may exceed this magnification but the resolution is diffraction limited. Using shorter wavelengths of light, such as the ultraviolet, is one way to improve the spatial resolution of the microscope as are techniques such as Near-field scanning optical microscope.
A stereo microscope is often used for lower-power magnification on large subjects.
Various wavelengths of light, including those beyond the visible range, are sometimes used for special purposes. Ultraviolet light is used to enable the resolution of smaller features as well as to image samples that are transparent to the eye. Near infrared light is used to image 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 emission from objects for viewing by eye or with sensitive cameras.
phase contrast microscope:Phase contrast microscopy is an optical microscopy illumination technique 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 staining to view the slide. This microscope made it possible to study the cell cycle.The Digital microscope appeared a few years ago, using optics and a charge-coupled device (CCD) camera to output a digital image to a monitor. This technology invented by Hirox offers a much higher depth of field and working distance as well as increased flexibility of inspection for large sized objects (NDT, skin, paintings) in a broad range of applications.
[edit] Electron Microscopes
Main article: Electron microscope
Three major variants of electron microscopes exist:
Scanning electron microscope (SEM): looks at the surface of bulk objects by scanning the surface with a fine electron beam and measuring reflection. May also be used for spectroscopy.
Transmission electron microscope (TEM): passes electrons completely through the sample, analogous to basic optical microscopy. 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 Tunneling Microscope (STM): is a powerful technique for viewing surfaces at the atomic level.
The SEM, TEM, STM are included in the scanning probe microscopy.
[edit] Established types of scanning probe microscopy
AFM, atomic force microscopy
Contact AFM
Non-contact AFM
Dynamic contact AFM
Tapping AFM
BEEM, ballistic electron emission microscopy
EFM, electrostatic force microscope
ESTM electrochemical scanning tunneling microscope
FMM, force modulation microscopy
KPFM, kelvin probe force microscopy
MFM, magnetic force microscopy
MRFM, magnetic resonance force microscopy
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/microscopy
SAP, scanning atom probe [5]
SECM, scanning electrochemical microscopy
SCM, scanning capacitance microscopy
SGM, scanning gate microscopy
SICM, scanning ion-conductance microscopy
SPSM spin polarized scanning tunneling microscopy
SThM, scanning thermal microscopy[2]
STM, scanning tunneling microscopy
SVM, scanning voltage microscopy
SHPM, scanning Hall probe microscopy
SSM, Scanning SQUID microscope
Of these techniques AFM and STM are the most commonly used followed by MFM and SNOM/NSOM.
[edit] Other microscopes
Scanning acoustic microscopes use sound waves to measure variations in acoustic impedance. Similar to Sonar in principle, they are used for such jobs as detecting defects in the subsurfaces of materials including those found in integrated circuits.
[edit] See also
Different microscopes
Wikimedia Commons has media related to: Microscopes
Acronyms in microscopy
Angular resolution
Bright field microscopy
Condensed Matter Physics
Confocal microscopy
Dark field microscopy
Digital microscope
Electron Microscope
Fluorescence interference contrast microscopy
Fluorescence microscope
Microscope image processing
Microscopy
Optical Microscope
Intel Play
Phase contrast microscopy
Microscope slide
Telescope
Timeline of microscope technology
X-ray microscope
Microscopy laboratory in: A Study Guide to the Science of Botany at Wikibooks
Laser capture microdissection
[edit] References
^ Ajram, K. (1992). The miracle of Islamic science. Knowledge House Publishers. pp. Appendix B. ISBN 0-911119-43-4.
^ [1] Timeline - History of Microscopes
^ Microscopes: Time Line
^ Stephen Jay Gould(2000). The Lying Stones of Marrakech, ch.2 "The Sharp-Eyed Lynx, Outfoxed by Nature". London: Jonathon Cape. ISBN 0224050443
^ Morita, Seizo. Roadmap of Scanning Probe Microscopy. 3 January 2007
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