Kats Final Chapter 10 pt1

The use of high-mAs, low-kVp and of slower image receptors reduces______ .

Fast image receptors have___ noise and low spatial resolution and low contrast resolution. 1)no Noise
2)Low Noise
3)High Noise

Fast image receptors have High noise and____ spatial resolution and low contrast resolution.
1)no spatial resolution 

2)Low spatial resolution 

3)High spatial resolution 

Radiographic noise has four components:

·        
The principal source of radiographic noise is 

Distribution of phosphor crystals in an intensifying screen is called 

Radiographic noise produced by the random interaction of x-rays with an intensifying screen. This effect is more noticeable when very high rare Earth systems are used at a high kVp.  this is called

Lower noise results in a better radiographic image because it improves contrast resolution.  
true or false

The Ability to image small objects that have high subject contrast is called.....

Spatial resolution improves as screen blur 1)decreases
2)Increases
3)No Change,

the ability to distinguish anatomical structures of similar subject contrast such as liver–spleen and gray matter–white matter.is

 refers to the ability to visualize recorded detail when image contrast and optical density (OD) are optimized.  

Degree of sharpness of structural lines on a radiograph. 

the random fluctuation in the OD of the image.

Sensitivity is the ability of the CCD to detect and respond to very____  levels of visible light 

________ is the ability of the CCD to respond to a wide range of light intensity, from very dim to very bright. 

The CCD has Lower sensitivity for radiation and a much wider dynamic range than screen-film image receptors. 
True or False

CsI/CCD is an indirect DR process by which x-rays are converted first to light and then to electric signal.  .
True or False

The percentage of the pixel face that is sensitive to x-rays is the ______. 

The fill factor is approximately___%; therefore, ___% of the x-ray beam does not contribute to the image.  

_________ in DR is pixel limited. 

a-____ is a direct DR process by which x-rays are converted to electric signal.  

special optics that can keep beam size shape and speed independent of the beam position

moves laser beam rapidly back and fourth across the screen to stimulate sequentaily  each point along the scar line

the _____ are used to collect as much of the emitted light from the screen and channel with minimal loss to the photo-detector where it is converted into a electrical image

the____ plays a crucial role in keeping the   stimulated light from entering the photo detector and swamping the desired image signal 

the___ converts the emited light photons into an electrical signal that can be processed into a digital image

______ refers to a continuously varying quantity; a digital system uses only two values that vary discretely through coding.  .