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Light Microscope
The optical microscope, also referred to as a light microscope, is a type of microscope that commonly uses visible spectrum, visible light and a system of lens (optics), 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 optical resolution, resolution and sample contrast (vision), contrast. The object is placed on a stage and may be directly viewed through one or two eyepieces on the microscope. In high-power microscopes, both eyepieces typically show the same image, but with a stereo microscope, slightly different images are used to create a 3-D effect. A camera is typically used to capture the image (micrograph). The sample can be lit in a variety of ways. Transparent objects can be lit from below and solid objects can be lit with light coming through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scientists Are Working In The Lab
A scientist is a person who researches to advance knowledge in an area of the natural sciences. In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engaged in the philosophical study of nature called natural philosophy, a precursor of natural science. Though Thales ( 624–545 BC) was arguably the first scientist for describing how cosmic events may be seen as natural, not necessarily caused by gods,Frank N. Magill''The Ancient World: Dictionary of World Biography'', Volume 1 Routledge, 2003 it was not until the 19th century that the term ''scientist'' came into regular use after it was coined by the theologian, philosopher, and historian of science William Whewell in 1833. History The roles of "scientists", and their predecessors before the emergence of modern scientific disciplines, have evolved considerably over time. Scientists of different eras (and before them, natural philosophers, mathematicians, natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microscope Simple Diagram
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. There are many types of microscopes, and they may be grouped in different ways. One way is to describe the method an instrument uses to interact with a sample and produce images, either by sending a beam of light or electrons through a sample in its optical path, by detecting photon emissions from a sample, or by scanning across and a short distance from the surface of a sample using a probe. The most common microscope (and the first to be invented) is the optical microscope, which uses lenses to refract visible light that passed through a thinly sectioned sample to produce an observable image. Other major types of microscopes are the fluorescence microscope, electron microscope (both the transm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereo Microscope
The stereo, stereoscopic or dissecting microscope is an optical microscope variant designed for low magnification observation of a sample, typically using light reflected from the surface of an object rather than transmitted through it. The instrument uses two separate optical paths with two objectives and eyepieces to provide slightly different viewing angles to the left and right eyes. This arrangement produces a stereoscopy, three-dimensional visualization of the sample being examined."Introduction to Stereomicroscopy" by Paul E. Nothnagle, William Chambers, and Michael W. Davidson, ''Nikon MicroscopyU''. Stereomicroscopy overlaps macrophotography for recording and examining solid samples with complex surface topography, where a three-dimensional view is needed for analyzing the deta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Contrast
Phase-contrast imaging is a method of imaging that has a range of different applications. It measures differences in the refractive index of different materials to differentiate between structures under analysis. In conventional light microscopy, phase contrast can be employed to distinguish between structures of similar transparency, and to examine crystals on the basis of their double refraction. This has uses in biological, medical and geological science. In X-ray tomography, the same physical principles can be used to increase image contrast by highlighting small details of differing refractive index within structures that are otherwise uniform. In transmission electron microscopy (TEM), phase contrast enables very high resolution (HR) imaging, making it possible to distinguish features a few Angstrom apart (at this point highest resolution is 40 pm). Atomic physics Phase-contrast imaging is commonly used in atomic physics to describe a range of techniques for dispersively i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near Point
In visual perception, the near point is the closest point at which an object can be placed and still form a focused image on the retina, within the eye's accommodation range. The other limit to the eye's accommodation range is the far point. A normal eye is considered to have a near point at about for a thirty year old. The near point is highly age dependent (see accommodation). A person with hyperopia or presbyopia would have a near point that is farther than normal. Sometimes, near point is given in diopters (see ), which refers to the inverse of the distance. For example a normal eye would have a near point of \frac = 9\ \text. Vision correction A person with hyperopia has a near point that is further away than the typical near point for someone their age, and hence the person is unable to bring an object at the typical near point distance into sharp focus. A corrective lens can be used to correct hyperopia by imaging an object at the typical near point distance onto a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angular Size
The angular diameter, angular size, apparent diameter, or apparent size is an angular separation (in units of angle) describing how large a sphere or circle appears from a given point of view. In the vision sciences, it is called the '' visual angle'', and in optics, it is the '' angular aperture'' (of a lens). The angular diameter can alternatively be thought of as the angular displacement through which an eye or camera must rotate to look from one side of an apparent circle to the opposite side. A person can resolve with their naked eyes diameters down to about 1 arcminute (approximately 0.017° or 0.0003 radians). This corresponds to 0.3 m at a 1 km distance, or to perceiving Venus as a disk under optimal conditions. Formulation The angular diameter of a circle whose plane is perpendicular to the displacement vector between the point of view and the center of said circle can be calculated using the formula :\delta = 2\arctan \left(\frac\right), in which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Real Image
{{citations needed, date=June 2019 In optics, an ''image'' is defined as the collection of focus points of light rays coming from an object. A real image is the collection of focus points actually made by converging/diverging rays, while a virtual image is the collection of focus points made by extensions of diverging or converging rays. In other words, a real image is an image which is located in the plane of convergence for the light rays that originate from a given object. Examples of real images include the image produced on a detector in the rear of a camera, and the image produced on an eyeball retina (the camera and eye focus light through an internal convex lens). In ray diagrams (such as the images on the right), real rays of light are always represented by full, solid lines; perceived or extrapolated rays of light are represented by dashed lines. A real image occurs at points where rays actually converge, whereas a virtual image occurs at points that rays appe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compound Microscope Geometric Optics
Compound may refer to: Architecture and built environments * Compound (enclosure) Compound, when applied to a human habitat, refers to a cluster of buildings in an enclosure, having a shared or associated purpose, such as the houses of an extended family (e.g. the Kennedy Compound for the Kennedy family). The enclosure may ..., a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive structures * Compound (migrant labour), a hostel for migrant workers such as those historically connected with mines in South Africa * The Compound, an area of Palm Bay, Florida, US * Komboni or compound, a type of slum in Zambia Government and law * Composition (fine), a legal procedure in use after the English Civil War ** Committee for Compounding with Delinquents, an English Civil War institution that allowed Parliament to compound the estates of Royalists * Compounding treason, an offence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telescope
A telescope is a device used to observe distant objects by their emission, Absorption (electromagnetic radiation), absorption, or Reflection (physics), reflection of electromagnetic radiation. Originally, it was an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects – an optical telescope. Nowadays, the word "telescope" is defined as a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Loupe
A loupe ( ) is a simple, small magnification device used to see small details more closely. They generally have higher magnification than a magnifying glass, and are designed to be held or worn close to the eye. A loupe does not have an attached handle, and its focusing lens(es) are contained in an opaque cylinder or cone. On some loupes this cylinder folds into an enclosing housing that protects the lenses when not in use. Optics Three basic types of loupes exist: * Simple lenses, generally used for low-magnification designs because of high optical aberration. * Compound lenses, generally used for higher magnifications to control optical aberration. * Prismatic, multiple lenses with prisms. Uses Loupes are used in many professions where magnification enables precision work to be done with greater efficiency and ease. Examples include surgery, dentistry, ophthalmology, the jewelry trade, gemology, questioned document examination, and watchmaking. Loupes are also somet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnifying Glass
A magnifying glass is a convex lens—usually mounted in a frame with a handle—that is used to produce a magnified image of an object. A magnifying glass can also be used to focus light, such as to concentrate the Sun's radiation to create a hot spot at the focus for fire starting. Evidence of magnifying glasses exists from antiquity. The magnifying glass is an icon of detective fiction, particularly that of Sherlock Holmes. An alternative to a magnifying glass is a sheet magnifier, which comprises many very narrow concentric ring-shaped lenses, such that the combination acts as a single lens but is much thinner. Use The convex lens of a magnifying glass can be used to produce a magnified image An image or picture is a visual representation. An image can be Two-dimensional space, two-dimensional, such as a drawing, painting, or photograph, or Three-dimensional space, three-dimensional, such as a carving or sculpture. Images may be di ... of an object. A magnify ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virtual Image
In optics, the ''image'' of an object is defined as the collection of Focus (optics), focus points of Ray (optics), light rays coming from the object. A ''real image'' is the collection of focus points made by Vergence (optics), converging rays, while a virtual image is the collection of focus points made by backward extensions of Beam divergence, diverging rays. In other words, a virtual image is found by tracing real rays that emerge from an optical device (lens, mirror, or some combination) backward to perceived or apparent origins of ray divergences. There is a concept ''virtual object'' that is similarly defined; an object is virtual when forward extensions of rays converge toward it. This is observed in ray tracing for a multi-lenses system or a diverging lens. For the diverging lens, forward extension of converging rays toward the lens will meet the converging point, so the point is a virtual object. For a (refracting) lens, the real image of an object is formed on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
