An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a higher resolving power than light microscopes and can reveal the structure of smaller objects. A scanning transmission electron microscope has achieved better than 50 pm resolution in annular dark-field imaging mode and magnifications of up to about 10,000,000× whereas most light microscopes are limited by diffraction to about 200 nm resolution and useful magnifications below 2000×.
Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures visible without a microscope. Although one may divide microscopic anatomy into organology, the study of organs, histology, the study of tissues, and cytology, the study of cells, modern usage places all of these topics under the field of histology. In medicine, histopathology is the branch of histology that includes the microscopic identification and study of diseased tissue. In the field of paleontology, the term paleohistology refers to the histology of fossil organisms.
Microscopy is the technical field of using microscopes to view objects and areas of objects that cannot be seen with the naked eye. There are three well-known branches of microscopy: optical, electron, and scanning probe microscopy, along with the emerging field of X-ray microscopy.
A microscope is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisible to the eye unless aided by a microscope.
A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the surface topography and composition of the sample. The electron beam is scanned in a raster scan pattern, and the position of the beam is combined with the intensity of the detected signal to produce an image. In the most common SEM mode, secondary electrons emitted by atoms excited by the electron beam are detected using a secondary electron detector. The number of secondary electrons that can be detected, and thus the signal intensity, depends, among other things, on specimen topography. Some SEMs can achieve resolutions better than 1 nanometer.
The optical microscope, also referred to as a light microscope, is a type of microscope that commonly uses visible light and a system of lenses to generate magnified images of small objects. Optical microscopes are the oldest design of microscope and were possibly invented in their present compound form in the 17th century. Basic optical microscopes can be very simple, although many complex designs aim to improve resolution and sample contrast.
Transmission electron microscopy (TEM) is a microscopy technique in which a beam of electrons is transmitted through a specimen to form an image. The specimen is most often an ultrathin section less than 100 nm thick or a suspension on a grid. An image is formed from the interaction of the electrons with the sample as the beam is transmitted through the specimen. The image is then magnified and focused onto an imaging device, such as a fluorescent screen, a layer of photographic film, or a sensor such as a scintillator attached to a charge-coupled device.
An X-ray microscope uses electromagnetic radiation in the soft X-ray band to produce magnified images of objects. Since X-rays penetrate most objects, there is no need to specially prepare them for X-ray microscopy observations.
A fluorescence microscope is an optical microscope that uses fluorescence instead of, or in addition to, scattering, reflection, and attenuation or absorption, to study the properties of organic or inorganic substances. "Fluorescence microscope" refers to any microscope that uses fluorescence to generate an image, whether it is a more simple set up like an epifluorescence microscope or a more complicated design such as a confocal microscope, which uses optical sectioning to get better resolution of the fluorescence image.
A micrograph or photomicrograph is a photograph or digital image taken through a microscope or similar device to show a magnified image of an object. This is opposed to a macrograph or photomacrograph, an image which is also taken on a microscope but is only slightly magnified, usually less than 10 times. Micrography is the practice or art of using microscopes to make photographs.
Characterization, when used in materials science, refers to the broad and general process by which a material's structure and properties are probed and measured. It is a fundamental process in the field of materials science, without which no scientific understanding of engineering materials could be ascertained. The scope of the term often differs; some definitions limit the term's use to techniques which study the microscopic structure and properties of materials, while others use the term to refer to any materials analysis process including macroscopic techniques such as mechanical testing, thermal analysis and density calculation. The scale of the structures observed in materials characterization ranges from angstroms, such as in the imaging of individual atoms and chemical bonds, up to centimeters, such as in the imaging of coarse grain structures in metals.
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 is generally dark.
The McCrone Research Institute is a not-for-profit educational and research organization for microscopy located in Chicago, Illinois. It was founded by Dr. Walter C. McCrone in 1960. With more than 30,000 enrollments since its incorporation, it is the largest private, independent, nonprofit microscopy and microanalysis institution in the United States dedicated solely to the teaching of microscopists. McCrone Research Institute maintains over one hundred polarized light and various other light microscopes in addition to electron microscopes, spectrometers, and scientific digital imaging systems for use in any of its over 50 intensive one-week courses offered each year.
The optical properties of all liquid and solid materials change as a function of the wavelength of light used to measure them. This change as a function of wavelength is called the dispersion of the optical properties. The graph created by plotting the optical property of interest by the wavelength at which it is measured is called a dispersion curve.
Maximilian Haider is an Austrian physicist.
Holographic interference microscopy (HIM) is holographic interferometry applied for microscopy for visualization of phase micro-objects. Phase micro-objects are invisible because they do not change intensity of light, they insert only invisible phase shifts. The holographic interference microscopy distinguishes itself from other microscopy methods by using a hologram and the interference for converting invisible phase shifts into intensity changes.
Dame Pratibha Laxman Gai-Boyes is a British microscopist and Professor and Chair of Electron Microscopy and former Director at The York JEOL Nanocentre, Departments of Chemistry and Physics, University of York. She created the atomic-resolution environmental transmission electron microscope (ETEM) and is an outspoken advocate for women with careers in science.
The American Microscopical Society (AMS) is a society of biologists dedicated to promoting the use of microscopy.
The Micro-Satellite à traînée Compensée pour l'Observation du Principe d'Equivalence (MICROSCOPE) is a 300-kilogram (660 lb) class minisatellite operated by CNES to test the universality of free fall with a precision to the order of 10−15, 100 times more precise than can be achieved on Earth. It was launched on 25 April 2016 alongside Sentinel-1B and other small satellites, and was decommissioned around 18 October 2018 after completion of its science objectives.
Scanning microscopy may refer to:
