Help
Options
Question
what are the layers of the IP in CR
click to flip
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't know
Question
what is the purpose of the backing
Remaining cards (31)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
diagnostic systems
| Question | Answer |
|---|---|
| what are the layers of the IP in CR | *backing *base *anti halo/reflective *phosphor *protective |
| what is the purpose of the backing | *mounted to the back of cassette *prevents handling artifacts *contains barcode *prevents static energy |
| what is the purpose of the base layer | support |
| what is the purpose of the anti halo/reflective layer | *prevents laser light from bouncing back and causing fog or noise *allows reflected light to be emitted to phosphor *anti-halo is blue *reflective is white |
| what is the purpose of the phosphor layer | *acquires latent image *site of f centers |
| what is the purpose of the protective layer | *tubeside *prevents handling artifacts *allows cleaning |
| what is S:N ratio | the ratio of useful informatin vs noise or unuseful information |
| what is contrast | density differences |
| what is the relationship between S:N ratio and contrast | direct |
| window level | controls brightness -direct relationship |
| window width | contrast(gray scale)(visibility of detail) -inverse relationship |
| what determines the maximum spatial resolution for a given sampling frequency by IRD | nyquest frequency |
| spatial resolution | the sharpness of structural edges recorded in the image |
| exposure latitude | range of exposures which produces optimal image with appropriate dose *since range is wider with digital radiography this can lead to dose creep |
| dynamic range | range of exposures that may be captured by a detector |
| bit depth | controls number of shades of gray that can be visualized -formula=2 to the nth(n=number of bits) |
| equalization | software function designed to even the brightness (density). light areas are made darker and dark areas lighter *good for tube placement in chest imaging |
| edge enhancement | *artificial increase in contrast at edge of structures *diamond view is the siemens term *also called high pass filtering(convolution) |
| smoothing | *software function to reduce the appearance of noise but causes loss of fine detail *also call low pass filtering(convolution) |
| stitching | *software that allows RT to place images together if too long for IR *scoliosis pt's *long bone measurement |
| what types of DR scintilators can we use today | *cesium iodide(indirect)(CCD) *godolinium oxysulfide(indirect)(CCD or TFT) |
| minimum response time | length of exposure required to produce an image |
| variable resistor(mA selector) | rheostat |
| measures electric potential(parallel circuit) | voltmeter |
| measures electric current(series circuit) | ammeter |
| transformer | increases or decreases voltage by fixed amount (AC only) |
| deadman switch | shuts off as let as you let off switch |
| anything that a radiographer will be touching is on the _____________ side of the circuit | primary(low voltage) |
| select mAs, unit starts at highest mA and shortest time. mA drops off during exposure with appropriate time changes. Used to get shortes time for mAs | falling load |
| kVp selector | autotransformer |
| conversion of AC to DC to apply to tube | rectification |
| where are rectifiers found | between secondary coil of step up transformer and tube so that current will flow in one direction from filament to anode |
Created by:
bigad1982
Popular Radiology sets