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P/N 56910COA
Reference
Glossary
Binary
Permitting two possibilities; for example, 0 or 1, ON or
OFF, black or white.
Bit
The smallest unit of computer memory.
A bit is either ON or OFF. The sensor captures an 8-bit
image. Each 8-bit pixel can display one of 256 shades
of gray. When the sensor converts the gray-scale
(8-bit) image to binary (1-bit) format, each pixel
displays as either black or white.
Depth of field
The area before and beyond the optimal point of
focus. More depth of field accommodates lens-to-
object variance (movement). Less depth of field
reduces background distraction.
Exposure time (Exposure)
The length of time the pixel array is exposed to light
during an image capture, specified in milliseconds
(ms).
FAIL
The judgment results are not acceptable based on
judgment criteria as taught.
Field of view (FOV)
The image area captured within the pixel array.
Focal length
The distance between the rear nodal point of a lens
and the focal plane, specified in millimeters. For
example, an 8 mm lens has a focal length of 8 mm,
and a 12 mm lens has a focal length of 12 mm (25
mm is approximately 1"). A shorter focal length
provides a wider field of view and less depth of field.
Gray scale
A range of shades from pure white to pure black.
Gray-scale thresholds
Two adjustable values between 0 (black) and 255
(white) representing two shades of gray within a 256-
level gray-scale.
The sensor judges each pixel as black or white
according to where its value falls in relation to the
upper threshold (highest number) and lower threshold
(lowest number).
Judgment
The process the sensor uses to determine the
outcome (PASS, FAIL, Fail High, or Fail Low) of the
image capture by comparing the pixel count of the
image to reference values.
Mask
A defined area within the ROI that is ignored during
judgment.
PASS
The judgment results are acceptable based on
judgment criteria as taught.
Pixel
The smallest “picture element” of an image for which
the sensor determines an average brightness value.
Each pixel within the sensor’s array is a discrete
photosensitive cell that can collect and hold a photo
charge.
Pixel array (Array)
The area on the sensor that captures the image – a
512 x 384 pixel grid.
Region of interest (ROI)
A defined area of the captured image within the pixel
array that is judged. The image outside of an ROI is
ignored.
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