Chapter 6 CCD/CMOS UPDATED
ACTUAL Exam Questions and CORRECT
Answers
charge-coupled devices (CCDS) - CORRECT ANSWER - The oldest indirect conversion
digital radiography systems used ________ to acquire the digital image.
scintillation/ lenses or fiber - CORRECT ANSWER - In a CCD system, x-ray photons
interact with a ______ material and the signal is transmitted by _____ or _____ optics to the
CCD.
size/ light to electrical charge - CORRECT ANSWER - During the transmission process,
the lenses reduce the ____ of the projected visible light image and transfer the image to one or
more small capacitors that convert ______ to _______.
analog-to-digital converter (ADC) - CORRECT ANSWER - This charge is stored in a
sequential pattern and released line by line and sent to an ___________.
photosensitive receptor - CORRECT ANSWER - A ___________ and electronics
embedded into a substrate material in a silicon chip make up a CCD.
Incident light - CORRECT ANSWER - _________ from a scintillator strikes the detector
and electron/hole pairs are produced in the silicon.
light - CORRECT ANSWER - The number of electron/hole pairs is related to the amount
of ______ that is absorbed.
electrostatic forces - CORRECT ANSWER - The electrons are held by _______ in the
array until the charge is read out to from the image.
, polysilicon layer, silicon dioxide layer, silicon substrate - CORRECT ANSWER - The chip
is made up of a ______ layer, _____ layer, and a _____.
polysilicon - CORRECT ANSWER - The _______ layer is coated with a photosensitive
material and contains electronic gates.
silicon dioxide/ silicon substrate - CORRECT ANSWER - The _______ layer is an
insulator and the _____ contains the charge storage area.
detector element (del) - CORRECT ANSWER - Each pixel or _______ contains three
electrodes that hold the electrons in a electrical potential wall.
voltage gates/ electrons - CORRECT ANSWER - The dels are formed by _______ that, at
readout, are opened and closed like gates to allow the flow of _____.
readout row/ "bucket brigade scheme" - CORRECT ANSWER - To collect the charge on
the silicon chips, the voltage sign is changed on the electrodes within each del, moving the
electrons by rows down the columns until the _______ is reached. This is known as what?
amplifier - CORRECT ANSWER - Once the readout row is reached, the data are sent
sequentially to the sense _____ and are then digitized.
electrons - CORRECT ANSWER - There can be issues with overfill in the dels, which
causes excessive _____ to spill out of the del into an adjacent del.
"blooming" - CORRECT ANSWER - This is handled by building overflow drains into the
array to reduce or prevent this "_____" effect.
5 cm x 5 cm - CORRECT ANSWER - Because of high cost of a CCD chip, it is not
practical to manufacture CCD chips any larger than _______.
ACTUAL Exam Questions and CORRECT
Answers
charge-coupled devices (CCDS) - CORRECT ANSWER - The oldest indirect conversion
digital radiography systems used ________ to acquire the digital image.
scintillation/ lenses or fiber - CORRECT ANSWER - In a CCD system, x-ray photons
interact with a ______ material and the signal is transmitted by _____ or _____ optics to the
CCD.
size/ light to electrical charge - CORRECT ANSWER - During the transmission process,
the lenses reduce the ____ of the projected visible light image and transfer the image to one or
more small capacitors that convert ______ to _______.
analog-to-digital converter (ADC) - CORRECT ANSWER - This charge is stored in a
sequential pattern and released line by line and sent to an ___________.
photosensitive receptor - CORRECT ANSWER - A ___________ and electronics
embedded into a substrate material in a silicon chip make up a CCD.
Incident light - CORRECT ANSWER - _________ from a scintillator strikes the detector
and electron/hole pairs are produced in the silicon.
light - CORRECT ANSWER - The number of electron/hole pairs is related to the amount
of ______ that is absorbed.
electrostatic forces - CORRECT ANSWER - The electrons are held by _______ in the
array until the charge is read out to from the image.
, polysilicon layer, silicon dioxide layer, silicon substrate - CORRECT ANSWER - The chip
is made up of a ______ layer, _____ layer, and a _____.
polysilicon - CORRECT ANSWER - The _______ layer is coated with a photosensitive
material and contains electronic gates.
silicon dioxide/ silicon substrate - CORRECT ANSWER - The _______ layer is an
insulator and the _____ contains the charge storage area.
detector element (del) - CORRECT ANSWER - Each pixel or _______ contains three
electrodes that hold the electrons in a electrical potential wall.
voltage gates/ electrons - CORRECT ANSWER - The dels are formed by _______ that, at
readout, are opened and closed like gates to allow the flow of _____.
readout row/ "bucket brigade scheme" - CORRECT ANSWER - To collect the charge on
the silicon chips, the voltage sign is changed on the electrodes within each del, moving the
electrons by rows down the columns until the _______ is reached. This is known as what?
amplifier - CORRECT ANSWER - Once the readout row is reached, the data are sent
sequentially to the sense _____ and are then digitized.
electrons - CORRECT ANSWER - There can be issues with overfill in the dels, which
causes excessive _____ to spill out of the del into an adjacent del.
"blooming" - CORRECT ANSWER - This is handled by building overflow drains into the
array to reduce or prevent this "_____" effect.
5 cm x 5 cm - CORRECT ANSWER - Because of high cost of a CCD chip, it is not
practical to manufacture CCD chips any larger than _______.
