Dynamic range

Question 1

what is dynamic range?

Answer 1

a method of describing the extent to which a signal can vary and still maintain accuracy. “the number of available choices”.

Question 2

What are the units for dynamic range?

Answer 2

Db.
Is a relative measurement, ratio

Question 3

What is threshold?

Answer 3

Weak signals below the systems detection zone.

Question 4

What is saturation?

Answer 4

Strong signals above the detection zone.

Question 5

The dynamic range of information….

Answer 5

Decreases the more it is processed.

Question 6

What is the dynamic range for the transducer?

Answer 6

120 Db

Question 7

What is the dynamic range for the scan converter?

Answer 7

40 to 50 Db. Half that of the transducer

Question 8

What is the dynamic range for the archive?

Answer 8

10 to 30 Db. Has the most narrow dynamic range.

Question 9

What is compression?

Answer 9

Technique that reduces the dynamic range of a signal without introducing errors.

Question 10

True or False, the human eye has less dynamic range that the systems display?

Answer 10

True

Question 11

True or False, the sonographer can adjust compression?

Answer 11

True

Question 12

As you turn the compression knob to the left do you increase or decrease the dynamic range?

Answer 12

Decrease the dynamic range

Question 13

As you turn the compression knob to the right do you increase or decrease the dynamic range?

Answer 13

Increase the dynamic range.

Question 14

To find the dynamic range, with an uncompressed signal do you add or subtract?

Answer 14

add

Question 15

To find the dynamic range with a compressed signal do you add or subtract?

Answer 15

subtract

Question 16

An uncompressed signal has a dynamic range of 85 Db. The signal undergoes 30 Db of compression. What is the dynamic range of the compressed signals?

Answer 16

85 Db- 30 Db = 55 Db

Answer 55 Db

Question 17

After compression, a signal within the ultrasound system has a dynamic range of 70 Db. The orginial signal was compressed by 40 Db. What is the dynamic range of the original uncompressed signal?

Answer 17

70 Db + 40 Db = 110 Db

Answer 110 Db

Question 18

As the dynamic range increases you will see an increase in what?

Answer 18

Shades of gray.

Question 19

Fewer shades of gray will have what?

Answer 19

1. fewer choices
2. Bi-stable (black and White only)
3. narrow dynamic range
4. High contrast

Question 20

More shades of gray will have what?

Answer 20

1. More choices
2. Gray scale
3. Wide dynamic range
4. Low contrast

Question 21

What is the highest component of dynamic range?

Answer 21

The transducer

Question 22

What is the smallest component of dynamic range?

Answer 22

Archive

Question 23

What component is in the half way point of dynamic range?

Answer 23

The scan converter

Question 24

What are the 3 rules of compression?

Answer 24

1. The largest signal remains the largest.
2. The smallest signal remains the smallest
3. The range of signals is reduced

Question 25

Which display is limited to a single pair of brightness or display levels?

Answer 25

Bistable

Question 26

All of the following are consistent with an image containing black and white only with no shades of gray except.

Answer 26

Wide dynamic range