Screen Characteristics pt 3

Question 1

What are Extrinsic speed factors?

Answer 1

outside influence

Question 2

What are the characteristics of Extrinsic speed factors?

Answer 2

1. Temperature
2. Kilovoltage

Question 3

What is the effect of temperature?

Answer 3

As temperature increases, screen speed decreases

Question 4

What is the effect of Kilovoltage in regards to calcium tungstate?

Answer 4

• speed is not affected by kV
• it remains the same regardless of kV applied

Question 5

What is the effect of Kilovoltage in regard to Rare earth?

Answer 5

phosphors react slow with low kV and faster with higher kV

Question 6

What is the advantage of Resolution?

Answer 6

patient dose is decreased by employing lower exposure factors

Question 7

What is the disadvantage of Resolution?

Answer 7

as screen speed is increased, resolution decreases

Question 8

How is resolution measured?

Answer 8

line pairs per millimeter (LP/mm) utilizing a resolution test pattern (either a bar or star type)

Question 9

Each line and the spaces between them will clearly separate. When they _________, this is the system’s limitation and is defined by its ____________.

Answer 9

• converge
• line pairs per millimeter (LP/mm)