Crosswords wk 1 Flashcards
Ratio of output illumination to input x-ray exposure is the
conversion factor
I.I. must have ___ equivlant
2 mm lead
I.I. is this type of barrier
Primary
Measure of overall increase in illumination level of I.I
Brightness gain
Process of e- produced from light stimulation
Photoemission
Photocathode is composed of ____ & ____.
Cesium and antimony
Ability to identify differences in brightness is called ____
Contrast perception
Type of vision produced by rods
Scotopic
Input phosphor converts x-rays to ____
light
Ability to perceive fine detail
visual acuity
Type of operator switch used in fluoro
dead man switch
Viewing distance is optimal at ___ to ___”
12-15 “
____ must be at least 3 mm of Al equivlant
filtration
Phosphor made out of zinc cadmium sulfide
Outputphospor
As magnification increases, pt. dose __
increases
One of the most important actions an operator can take to reduce pt. dose
collimate
Composition of input phosphor
Cesium iodide
brightness gain can degrade up to ___ per year due to “Aging”
10 %
type of vision produced by cones
Photopic
Distortion resulting from concave input phosphor hitting a flat output phosphor
Pincushion
What is the most common camera tube that results in good resolution/ moderate image lag
Vidicon
Blurring of the image during camera movement, common in vidicon
Lag
Grainy appearance due to not enough x-ray photons hitting the I.I
Quantum mottle
Frames per second produced by video monitor
30
Focal length divided by the diameter of the lens
F-number
Beam splitting mirror allows ___ of light to go to tv camera
10 %
Pattern of 525 horizontal scan line
raster pattern
static high quality images obtained at over 100 mA
spot film
supplies electrons in camera tube via thermionic emission
electron gun
fall off of brightness at the periphery of the image
vegnetting
High resolution camera with less lag, but more quntum mottle
Plumbicon
Dose is 20-50 times higher than regular fluoro
Photospot
Generally accepted to have a value of .7
Kell factor
