Term
aperature diaphragm
cones and cylinders
variable aperature collimator (PBL) |
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Definition
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Term
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Definition
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Term
simplest type of all BLDs
commonly used at head units |
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Definition
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Term
| disadvantage of aperature diaphragm |
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Definition
| fixed opening that leaves an unexposed border on each edge of radiograph |
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Term
useful beam in in circular shape
widely used in dental radiography
difficult to align |
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Definition
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Term
| most common BLD and most efficient |
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Definition
| Variable aperature collimator |
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Term
| Variable aperature collimator must be accurate to within ___% of SID |
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Definition
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Term
| the filtration afforded by glass envelope, oil, and glass window |
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Definition
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Term
| inherent filtration is usually ___ |
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Definition
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Term
| a thin sheet of aluminum placed between protective tube housing and external housing AND mirror inside the collimator |
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Definition
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Term
| added filtration equals ___ |
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Definition
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Term
| added filtration results in ___ energy, ___ penetrability, and ___ quality beam |
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Definition
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Term
| methods used to avoid repeat radiographs |
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Definition
proper technique
proper positioning
appropriate marker
correct patient identification |
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Term
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Definition
good patient instructions
fast film/screen combo
immobilization
shorter exposure times |
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