171 Flashcards
(16 cards)
What are the two types of signals in radiography?
Analog and Digital
Analog signals are continuous electronic signals, while digital signals are analog signals converted to numeric data.
How are analog radiographic images created?
X-ray energy is converted to light, affecting film and causing a chemical change
The film records the light waves exactly as they were in the pattern of tissue radiographed.
What is the process of digital conversion in radiographic imaging?
Electronic signals are sent to ADC; computer creates a digital data stream
The number array is converted to a visible image.
What are the components of digital radiographic imaging?
Digital receptor, CR or DR, electronic/computer processing
Radiation is detected and converted to an electronic signal, which is then converted to numeric data.
What is a matrix in digital imaging?
A series of boxes laid out in rows and columns
Each matrix box displays a numeric value.
What is a pixel in the context of digital images?
Individual matrix boxes, also known as picture elements
Pixels are the smallest units of a digital image.
How is matrix size determined?
By the total number of pixels in the matrix
It is calculated by multiplying the number of pixels in rows by the number in columns.
What does FOV stand for in digital imaging?
Field of view
FOV is determined by the size of the detector.
What happens to image quality when matrix size increases?
Image quality increases
A greater matrix size means more pixels and smaller pixels.
What is pixel pitch?
The spacing between pixels, measured from center to center
Smaller pixel pitch leads to better image resolution.
What does pixel bit depth determine?
The number of shades of gray displayed
It is influenced by the attenuation of x-rays passing through tissue.
What is the effect of higher bit depth on image quality?
It demonstrates more shades of gray and improves contrast resolution
More structures become visible.
What happens to pixel size when FOV decreases?
Pixel size decreases
This occurs when the matrix size is fixed.
True or False: Smaller pixels improve image quality.
True
Smaller pixels lead to better resolution.
What increases when pixel density increases?
Spatial resolution increases
More pixels in one area lead to better detail.
What does an increase in bit depth lead to?
More gray shades displayed and increased contrast resolution
This allows for better differentiation between similar tissues.
