| BAD | biological aerosol detection; British Association of Dermatologists |
|---|---|
| BCW | biological and chemical warfare |
| BDS | Bachelor of Dental Surgery; biological detection system; Blessed Dementia Scale |
| BEAR | biological effects of atomic radiation |
| BEI | back-scattered electron imaging; biological exposure indexes; butanol-extractable iodine |
| comparator microscope | <instrument> A device constructed with one or more microscope's having micrometer eyepieces used to measure dimensional changes during setting or temperature changes. (05 Mar 2000) |
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| compound microscope | <instrument> A microscope (an optical instrument that augments the power of the eye to see small objects) which consists of two microscopes in series, the first serving as the ocular lens (close to the eye) and the second serving as the objective lens (close to the object to be viewed). Credit for creating the compound microscope goes usually to the Dutch spectaclemakers Hans and Zacharias Janssen who in 1590 invented an instrument that could be used as either a microscope or telescope. The compound microscope has evolved into the dominant type of optical microscope today. (12 Dec 1998) |
| confocal microscope | <instrument> A microscope that allows the observer to visualise objects in a single plane of focus, thereby creating a sharper image (usually the objects are fluorescent molecules); a refinement of this microscope uses optical sectioning and a computer to record serial sections. This permits three-dimensional reconstruction. (05 Mar 2000) |
| polarising microscope | <instrument> A microscope equipped with a polarising filter below and above the specimen which forms an image by the influence of specimen birefringence on polarised light; the polarising direction of the two filters is typically adjustable which, together with a graduated rotating stage, permits measurement of the angular value of different refractive indices in either biological or chemical specimens. (05 Mar 2000) |
| polarized light microscope | <instrument, microscopy> A microscopical polarizcope, i.e., a compound microscope which is equipped with two polars and a Bertrand lens, chemists and mineralogists are the principal users. (05 Aug 1998) |
| scanning electron microscope | <instrument> An electron microscope in which the image is formed by a beam synchronised with an electron probe scanning the object. The intensity of the image forming beam is proportional to the scattering or secondary emission of the specimen where the probe strikes it (05 Aug 1998) |
| X-ray microscope | <instrument> A microscope in which images are obtained by using X-rays as an energy source that are recorded on a very fine-grained film, or the image is enlarged by projection; if film is used, it may be examined with the light microscope at fairly high magnifications. (05 Mar 2000) |
| simple microscope | <instrument> A microscope that has a single magnifying lens. (05 Mar 2000) |
| slit microscope | <instrument, microscopy> A term applied to particles less than 0.1 ~m in diameter, hence too small to be truly resolved by the light micro- scope. Under the ultramicroscope they look like stars in the sky. Their differences in size are merely indicated by differences in brightness. (05 Aug 1998) |
| stereoscopic microscope | <instrument> A microscope having double eyepieces and objectives and thus independent light paths, giving a three-dimensional image. (05 Mar 2000) |
| stroboscopic microscope | <instrument> A microscope that has a light source that flashes at a constant rate so that an analysis of the motility of an object may be made; it may be used for high speed or low speed (time-lapse) cinephotomicrography. (05 Mar 2000) |
| dark-field microscope | <instrument> A microscope that has a special condenser and objective with a diaphragm or stop that scatters light from the object observed, with the result that the object appears bright on a dark background. (05 Mar 2000) |
| surgical microscope | <instrument> A binocular microscope used to obtain good visualization of fine structures in the operating field; in the standing type of microscope, a motorised zoom lens system operated by hand or foot controls provides an adjustable working distance; in headborne models, interchangeable oculars provide the magnification needed. Synonym: operating microscope. (05 Mar 2000) |
| infrared microscope | <instrument> A microscope that is equipped with infrared transmitting optics and that measures the infrared absorption of minute samples with the aid of photoelectric cells; images may be observed with image converters or television. (05 Mar 2000) |
| interference microscope | <instrument> A specially constructed microscope in which the entering light is split into two beams which pass through the specimen and are recombined in the image plane where the interference effects make the transparent (invisible) refractile object details become visible as intensity differences; permits measurements of light retardation, index of refraction, and thickness and mass of specimen; it is useful in the examination of living or unstained cells. (05 Mar 2000) |