Equipment Operation and Quality Control 1.2 Imaging equipment

The total brightness gain of an image intensifier is the product of

1. flux gain


2. minification gain


3. focusing gain

A
 
1 only 


B
 
2 only 


C
 
1 and 2 only 


D
 
1 and 3 only

The output phosphor is only a fraction of the size of the input phosphor, and this decrease in image size represents brightness gain, termed _______

The ratio of the number of x-ray photons at the input phosphor compared to the number light photons at the output phosphor is termed ______

Total brightness gain is equal to the product of _____ gain and ___ gain

Which of the following combinations would pose the least hazard to a particular anode?



A
 
0.6-mm focal spot, 75 kVp, 30 mAs 


B
 
0.6-mm focal spot, 85 kVp, 15 mAs 


C
 
1.2-mm focal spot, 75 kVp, 30 mAs 


D
 
1.2-mm focal spot, 85 kVp, 15 mAs

Light-sensitive AEC devices are known as



A
 
phototimers 


B
 
ionization chambers 


C
 
sensors 


D
 
backup timers

If a high-voltage transformer has 100 primary turns and 50,000 secondary turns and is supplied by 220 V and 100 A, what are the secondary voltage and current?



A
 
200 A and 110 V 


B
 
200 mA and 110 kVp 


C
 
20 A and 100 V 


D
 
20 mA and 100 kVp

Total brightness gain is equal to the product of _____ gain and flux gain

Which of the following combinations would deliver the least amount of heat to the anode of a three-phase, 12-pulse x-ray unit?



A
 
400 mA, 0.12 s, 90 kVp 


B
 
300 mA, ½ s, 70 kVp 


C
 
500 mA, 1/30 s, 85 kVp 


D
 
700 mA, 0.06 s, 120 kVp

The device that receives the remnant beam, converts it into light, and then increases the brightness of that light is the



A
 
charge-coupled device (CCD) 


B
 
spot-film camera 


C
 
image intensifier 


D
 
television monitor

Which of the following is a type of television camera tube that converts a visible image on the output phosphor of the image intensifier into an electronic signal?



A
 
Ionization chamber 


B
 
Vidicon 


C
 
Charge-coupled device 


D
 
Cathode ray tube

 Ionization chambers (A) are found in an automatic exposure control (_____) system.

As the x-ray tube filament ages, it becomes progressively thinner because of evaporation. The vaporized tungsten is frequently deposited on the window of the glass envelope. This may

1.	act as an additional filter.
2.	reduce tube output.
3.	result in arcing and tube puncture.

A
 
1 only 


B
 
1 and 2 only 


C
 
2 and 3 only 


D
 
1, 2, and 3

The movement of the IP through the transport system of a CR reader is referred to as the:



A
 
Slow-scan direction 


B
 
Charge-coupled direction 


C
 
Nyquist direction 


D
 
Fast-scan direction

This light moves back and forth very rapidly to scan the PSP transversely, in a raster pattern, and this movement of the laser beam across the PSP is therefore called the _____direction 

Deposition of vaporized tungsten on the inner surface of the x-ray tube glass window

1. acts as additional filtration


2. results in increased tube output


3. results in anode pitting

A
 
1 only 


B
 
1 and 2 only 


C
 
2 and 3 only 


D
 
1, 2, and 3

Which of the x-ray circuit devices shown in Figure 6–5 operates on the principle of self-induction?







A
 
Number 1 


B
 
Number 3 


C
 
Number 5 


D
 
Number 7

The image intensifier's input phosphor differs from the output phosphor in that the input phosphor



A
 
is much larger than the output phosphor 


B
 
emits electrons, whereas the output phosphor emits light photons 


C
 
absorbs electrons, whereas the output phosphor absorbs light photons 


D
 
is a fixed size, and the size of the output phosphor can vary

It receives the remnant radiation emerging from the patient and converts it into a fluorescent light image

The fluorescent light image strikes the ______ and is converted to an electron image, which is focused by the electrostatic lenses to the small output phosphor.

Which of the following can record up to twelve images per second during conventional fluoroscopy?



A
 
Cassette-loaded spot film 


B
 
Flat panel image receptor 


C
 
Photospot camera film 


D
 
Direct exposure film

The following are disadvantages of a capacitor-discharge mobile unit, except:



A
 
The mAs increases during the exposure, called “mAs creep” 


B
 
The capacitor may continue to discharge after the exposure 


C
 
The actual kilovoltage achieved during an exposure is significantly lower than the set kVp 


D
 
At lower kVp settings, the capacitors discharge more slowly and, therefore, a considerable residual kV may exist after the desired exposure time

Which of the following techniques is used to evaluate the dynamics of a part?



A
 
Fluoroscopy 


B
 
Stereoscopy 


C
 
Tomography 


D
 
Phototiming

Using a multifield image intensifier tube, which of the following input phosphor diameters will provide the greatest magnification?



A
 
35 cm 


B
 
25 cm 


C
 
17 cm 


D
 
12 cm

A device contained within many CR readers that functions to convert light energy released by the PSP into electrical energy, is called a:



A
 
Transilluminator 


B
 
Photomultiplier tube 


C
 
Light gate 


D
 
Penetrometer

:
In fluoroscopy, the automatic brightness control is used to adjust the



A
 
kVp and mA 


B
 
backup timer 


C
 
milliamperage (mA) and time 


D
 
kilovoltage (kV) and time