Photometric Quantities
What is the science of the response of the human eye to light?
Photometry
What type of state of matter is a liquid crystal?
A state between a liquid and a solid
Preprocessing is done...
Automatically
Postprocessing is done...
Manually
PACS stands for
Picture archiving and communication system
What is the basic photometric unit?
Lumen
The number of pixels
Define preprocessing
The ability to manipulate the image before its displayed
Define postprocessing
Anything that can be done to the digital image after it is acquired by the imaging system
How are image file sizes determined?
Matrix size and grayscale bit depth
Which law describes the luminous intensity of a digital display device?
Cosine Law
Define aperature ratio
The portion of the pixel face that is available to transmit light
How is flatfielding accomplished?
Through automatic calibration images called offset images and gain images
Pixel shift
What are the four principal components of PACS?
Image acquisition, display, network, storage
Which law describes the decrease in luminous intensity when the distance from the source of light increases?
Inverse Square Law
What is visible light emitted by a diode when electrically stimulated?
Electroluminescence
What is a similar artifact to ghosting in DR?
Image lag
Describe annotation
The process of adding text to an image
What is the individual device in a network of computers that are connected to one another?
Clients
How is a digital display monitor best viewed?
Straight on
What improves with the use of higher megapixel digtial display devices?
Spatial resolution
How are pixel defects corrected?
Signal interpolation
What is it called when you change image contrast by amplifying changes in anatomy or disease to digitally eliminate certain structures to see others clearly?
Subtraction
DICOM stands for
Digital Imaging and Communications in Medicine