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A curved mirror is a mirror with a curved reflecting surface. The surface may be either convex (bulging outward) or concave (recessed inward). Most curved mirrors have surfaces that are shaped like part of a sphere, but other shapes are sometimes used in optical devices. The most common non-spherical type are parabolic reflectors, found in ...
Mouth mirror. A mouth mirror or dentist's mirror is an instrument used in dentistry. The head of the mirror is usually round, and the most common sizes used are No. 4 (⌀ 18 mm) and No. 5 (⌀ 20 mm). [1] A No. 2 is sometimes used when a smaller mirror is needed, such as when working on back teeth with a dental dam in place.
A head mirror is a simple diagnostic device, stereotypically worn by physicians, but less so in recent decades as they have become somewhat obsolete. [1] A head mirror is mostly used for examination of the ear, nose and throat (ENT). It comprises a circular concave mirror, with a small hole in the middle, and is attached to a headband.
Katz extractor. to remove nasal foreign body. Bull's eye lamp. source of light; exiting lens is convex and produces a divergent beam of light. Speculum. to dilate orifices and to see inside. •Thudichum's nasal speculum. -do-; short blades ( uses: anterior rhinoscopy - to see the Little's area, ant-inferior part of nasal septum, anterior part ...
The dentist or dental auxiliary use dental mirrors to view a mirror image of the teeth in locations of the mouth where visibility is difficult or impossible. They also are used for reflecting light onto desired surfaces, and for retraction of soft tissues to improve access or vision. Pig tail dental explorer
Elevator (dental) Elevators (also known as luxators) are instruments used in dental extractions. They may be used to loosen teeth prior to forceps extraction, to remove roots or impacted teeth, when teeth are compromised and susceptible to fracture or when they are malpositioned and cannot be reached with forceps. [1]
A convex secondary mirror is placed just to the side of the light entering the telescope, and positioned afocally so as to send parallel light on to the tertiary. The concave tertiary mirror is positioned exactly twice as far to the side of the entering beam as was the convex secondary, and its own radius of curvature distant from the secondary.
The focal length is positive for a concave mirror, and negative for a convex mirror. In the sign convention used in optical design, a concave mirror has negative radius of curvature, so =, where R is the radius of curvature of the mirror's surface. See Radius of curvature (optics) for more information on the sign convention for radius of ...