High spatial resolution and high contrast resolution require_____ noise and slow image receptors. .
1) low
2)high
low
Higher______ density reduces the contrast of the radiographic image.
fog
What term is used to define the proper quantity for expressing image intensification.
conversion factor
a thin metal layer of cesium and antimony
The photocathode
In fluoroscopy, what provides better spatail resolution, better contrast resolution but at a higher patient dose.
magnification mode
Why is pulse progressive fluoroscopy necessary in digital fluoroscopy?
a. digital fluoroscopy is opereated in radiographic mode
b. to prevent thermal over loading
c. to reduce patient dose
a and b only
b and c only
c only
a and c
a,b,and c
a b c
The light intensity produced at the output phosphor compared to the light produced at the input phosphor is
increased by 50 to 75 times
On the television monitor, a bright spot is the result of
a. a brighter fluorescence of the phosphor due to a greater number of electrons leaving the electron gun
b. an increased video signal strength from the camera tube
c. an increased intensity of light reaching the camera tube from the output phosphor of the image intensifier
a
a and b
c
a, b and c
a b c
The output phosphor is
B)
what is a
anode
what is B
electrostatic Lenses
what is C
input phosphor
what is D
photocathode
Conversion from remnant x-ray photons to light photons occurs @ __________ ?
C
Where is the electron beam focused?
B
Where are photo-electrons converted to visible light
A
As it pertains to digital radiography_______________ releases photo-electrons when struck by light photons and _________ releases light when struck by photo-electrons.
A)photocathode
input phosphor
B)photocathode
output phosphor
C)input phosphor
output phosophr
D)output phoshor
input phoshor
B
The ability to digitally record a small object, its accuracy and clarity is the definition of which of the following?
B)
A decrease in the SNR will result in all of the following except:
D)
All are advantages of television image monitoring of fluoroscopy except:
B)
All of the following are advantages of flat panel image receptors except:
A)
How is the television image formed during fluoroscopy?
C)
Which component of the digital fluoroscopy system converts the acquired electrical signals into a recognizable digital form for the display device?
D)
Which portion of the image intensifier tube receives the remnant radiation from the patient?
D)
Which term is defined as the ratio of the number of light photons at the output phosphor to the number of x-rays at the input phosphor?
D)
Automatic brightness control is designed to compenstate for changes in
C)
When the maginification mode is operated
B)
What camera tube is most often used
C)
During digital fluoroscpy, the image receptor is the
C)
The sensitive input surface of the television camear tube is smaller than the output phosphor of the image intensifer tube.
True or False
what is a