Unit 8 - Spacial Resolution & Detail

________ is the degree of geometric sharpness of the structural lines recorded on an image
- Definition
- Sharpness
- Resolution

_______ is a term applied to a digital image recorded as:
- The ability of an imaging system to accurately display objects in 2 dimensions

Recorded Detail Vs. Visibility of Detail

- ________ is a geometric property that is not affected by the photographic properties of IR exposure & contrast

Assessing Recorded Detail
- The recorded detail of an image can be assessed visually by evaluating the _____ of the anatomical structural lines.
— Any image by size and/or shape will have ____ recorded detail 
Recorded detail can also be assessed by using a resolution tool

The spatial resolution of a digital imaging system is dependent on:
____
____
____

Spacial resolution measures for digital imaging systems:
______
______
______
______

Point Spread Function
- Expresses the ____ of an image
- Determined by complex mathematical measurement of an image produced by a single point
- Relates to _____ or blur

Spacial Frequency
- Relates the number of ___ ___ in a given length
- Determined by measuring the distance between pairs of lines from one another & then expressing them as cycles per unit of length (c/mm or c/cm)

High frequency signal = _____ spacial resolution
Low frequency signal = ______ spacial resolution

Modular Transfer Function (MTF)
____ measures the accuracy of an image compared to the original object on a scale of __ to __.

- Determined by mathematically calculating the % of object contrast recorded.
—— MTF of __ = imaging system produces an image that appears exactly as the object
—— MTF of __= no signal nor image

______
- refers to background information received by the IR
- If significantly less than the amount of information coming from the IR, computer processing algorithms filter it out
- Rising noise levels degrade the image
—— ____ Noise - insufficient amount of photons reaching the IR results in blotchy or mottled image.

Factors that Affect Recorded Detail
- Controlling factors
____
____
____

____: distinct, sharp area seen within the center of an image

____: blurry, unsnarl area seen at the periphery (edges) of an image - negatively affects recorded detail

The size of the focal spot is controlled by the ____________

As focal spot size is increased, penumbra ____ & detail ____
As focal spot size is decreased, penumbra ____ & detail _____

The relationship between SID & detail is ___:
— As SID is increased, penumbra/size distortion (magnification) ____ & detail ____