QA 6

adv of CRT

wider viewing angle

LCD adv

less energy, less heat, better luminance, & greater res

AMOLED adv

Activates pixels 1000x faster than LCD, higher res (more pixels)

Wide viewing angle, doesn't need LED backlighting

test pattern for daily monitor test

SMPTE test pattern

what can SMPTE test for

contrast, res, luminance, distortion

what to LF in geo distortion

Open test pattern & check for geo distortion

what to LF in resolution

lettering/numbers checked for clarity (determines resolving capabilities)

luminance is assessed by

evaling 5% & 95% on test pattern

daily monitor tests

geo distortion, res, luminance, general appearance

monthly monitor tests

Geometric distortions

Display reflection

Luminance response

Luminance spatial & angular dependencies

Display resolution

Display noise

Veiling glare

Display chromaticity

who recommends monthly monitor tests

AAPM

what test pattern for geometric distortions

TG18QC

what test pattern for display reflection

TG18AD Test Pattern

What is luminance response

determines if monitor displays same luminance lvl visualized using the test pattern

what test pattern for luminance response

TG18CT

what is spatial luminance

eval non-uniformity of luminance that stems from design of display monitor

what candela specifications for spat luminance

250 candela

angular luminance def

how viewing angle affects display luminance (assessed for appropriate viewing angles)

What test pattern is used for display resolution

TG18QC & TG18CX pattern

what is veiling glare

light that scatters inside display monitor

what test pattern is used for veiling glare

TG18GV test pattern

what is display chromaticity

determines if display of a color monitor (or gray) is uniform

what test pattern is used for Display chromaticity

TG18UN80 test pattern

how often is fluoro testing done

acceptance, every 6 months, maintenance

tests that eval normal fluoro functions also eval

spat res, contrast, uniformity, linearity, rad exp, artifacts

what are the components of a fluoro phantom

- Step wedge that simulates subject density differences

- Pieces of bone

- Resolution patterns in middle layers for spat res

- Tubes filled w iodinated contrast & epoxy to sim contrast-filled blood vessels

what is spat uniformity (fluoro)

measure subtracted image from phantom; measures amount of distortion in image

what is Low contrast assessment (fluoro)

digital subtraction at 70 kVp using phantom w/ & w/o hollow tubes simming BV

what reading do you take from low contrast assessment (fluoro)

Reading from smallest tube is compared to vendor's specifications in last test

what does Contrast linearity measure

measures avg pixel value for tubes that sim contrast filled BV

how is rad exp measured

measured in entrance skin exp, between grid & image intensifier, & as scatter

where is entrance exp measured

between phantom & table (taken UNDERNEATH phantom)

how to assess artifact eval

digital subtraction w/ nothing to subtract used to eval artifacts (blank image)

how to take spat res measurement

Spat res patterns embedded in digital fluoro phantom to indicate spat res

test pattern for noise

G18AFC test pattern