Confocal microscopy is an imaging technique used to increase micrograph contrast and/or to reconstruct three-dimensional images by using a spatial pinhole to eliminate out-of-focus light or flare in specimens that are thicker than the focal plane. This technique has been gaining popularity in the scientific and industrial communities. Typical applications include life sciences and semiconductor inspection. A micrograph is a photograph or similar image taken through a microscope or similar device to show a magnified image of an item. ... This article or section is in need of attention from an expert on the subject. ... Reconstruct, or reconstruction could mean : To rebuild, usually a building The process of creating a three dimensional object from images. ... Photograph of NASA lunar lander containing lens flare. ... The focal plane of a lens is a plane that is perpendicular to the axis of the lens and passes through its focus. ... Biology studies the variety of life (clockwise from top-left) E. coli, tree fern, gazelle, Goliath beetle Biology is the science of life (from the Greek words bios = life and logos = word). ... A semiconductor is a solid whose electrical conductivity can be controlled over a wide range, either permanently or dynamically. ...

Basic concept

The principle of confocal imaging was patented by Marvin Minsky in 1961. In a conventional (i.e., wide-field) fluorescence microscope, the entire specimen is flooded in light from a light source. Due to the conservation of light intensity transportation, all parts of specimen throughout the optical path will be excited and the fluorescence detected by a photodetector or a camera. In contrast, a confocal microscope uses point illumination and a pinhole in an optically conjugate plane in front of the detector to eliminate out-of-focus information. Only the light within the focal plane can be detected, so the image quality is much better than that of wide-field images. As only one point is illuminated at a time in confocal microscopy, 2D or 3D imaging requires scanning over a regular raster (i.e. a rectangular pattern of parallel scanning lines) in the specimen. The thickness of the focal plane is defined mostly by the square of the numerical aperture of the objective lens, and also by the optical properties of the specimen and the ambient index of refraction. Marvin Lee Minsky (born August 9, 1927), sometimes affectionately known as Old Man Minsky, is an American cognitive scientist in the field of artificial intelligence (AI), co-founder of MITs AI laboratory, and author of several texts on AI and philosophy. ... In biology, specimen is an individual animal or a plant or a microorganism that is used as a representative to study the properties of the whole population of that species. ... In physics, intensity is a measure of the time-averaged energy flux. ... Photosensors or photodetectors appear in several varieties: Photoresistors or Light Dependant Resistors (LDR) which change resistance when illuminated Photovoltaic cells or solar cells which produce a voltage and supply an electric current when illuminated Photodiodes which can operate in photovoltaic mode or photoconductive mode Phototubes containing a photocathode which emits... Large format camera lens. ... Numerical aperture is a technical term of multiple uses: Numerical aperture of optical telecommunication fiber Numerical aperture in microscopy This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... An objective lens is the lens in a microscope, telescope, camera or other optical instrument, that receives the first light rays from the object being observed. ...

Category

Three types of confocal microscopes are commercially available: Confocal laser scanning microscopes, spinning-disk (Nipkow disk) confocal microscopes and Programmable Array Microscopes (PAM). Generally speaking, confocal laser scanning microscopy yields better image quality but the imaging frame rate is very slow (less than 3 frames/second); spinning-disk confocal microscopes can achieve video rate imaging---desired for dynamic observations. Confocal laser scanning microscopy (CLSM or LSCM) is a valuable tool for obtaining high resolution images and 3-D reconstructions. ... A Nipkow disk is a mechanical, geometrically operating image scanning device (by itself, it performs neither image acquisition or reproduction), invented by Paul Gottlieb Nipkow, which was primarily used as a fundamental component in mechanical television. ... Frame rate, or frame frequency, is the measurement of how quickly an imaging device produces unique consecutive images called frames. ...

External links

• Nikon's MicroscopyU --- very comprehensive introduction to Confocal Microscopy.
• Emory’s Physics Department --- a very comprehensive introduction to confocal microscopy and fluorescence
• The Science Creative Quarterly's overview of confocal microscopy - high res images also available.
• Programmable Array Microscope -