Image Receptors Flashcards
What type of x-rays use direct film image production?
intra oral
what is direct film image production?
x-rays act directly on silver halide crystals in film emulsion
what type of x-rays use indirect film image production?
extra-oral
what is indirect film?
light from intensifying screens act on silver halide crystals in film emulsion
what are the 2 types of digital image production?
solid state
PSP
What type of sensors produce solid state digital images?
CCD or CMOS
What type of digital image production is tolerated better?
PSP
What is a phosphor plate?
storage plate that converts existing film based imaging system to a digital format that can be integrated into a computer or network system
what part of the phosphor plate is exposed to x-ray photons and scanned by the red laser?
phosphor layer
what produces a latent image?
x-ray energy stored in the electrons of the phosphor crystals (trapped signal)
in PSP, what is released as blue light?
stored energy
in PSP, what converts light to a digital signal?
ACD
In PSP, what represents the shades of grey which form the image on the monitor?
numerical value assigned to each pixel according to the intensity of detected light
how is the image on the phosphor plate erased?
exposing the phosphor to bright light - releases any remaining trapped energy in the phosphor electrons
what is the phosphor coating on the phosphor plate?
barium fluoride
What is CCD?
Charged-coupled device
what is CCD used for?
digital radiography for the indirect conversion of x-ray photons into an electric charge
what gives off light in CCD?
X-rays hit the scintillator layer within the sensor
what makes up pixels of an CCD image?
light hits the photosensitive cells within a very thin piece of silicon
in CCD what is converted into an electrical signal?
the charge electrons within each pixel being released
what is converted to produce an image in CCD?
ELECTRICAL SIGNAL
What differs CCD to CMOS?
CCD - pixels connected to form lines of pixels
CMOS - individual pixels
what is exposure?
the amount of x-rays to produce an image
what is PACS?
picture archiving and communication system
what are 0, 1, 2 PSP sizes used for?
periapical and bitewings
what are 0, 1 PSP sizes used for?
periapical anterior mouth of adult and all regions for children
what is 2 PSP size used for?
posterior mouth of adults
what is size 4 PSP used for?
occlusal