Document #OPM/1300, Revision B
CONFIDENTIAL
© 2013 Copyright VTS Medical Systems, LLC
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Glossary
Backlight Brightness:
The intensity of light emitted from the LCD Display. This control is similar to the
effect of changing the light behind a stained glass window. As the illumination is increased the overall light
output of the image is increased. The proper adjustment takes into consideration the ambient light in the
room. For a brightly lit room, the brightness of the display may be increased to improve the visibility of the
image. In a dimly lit room, the brightness may be decreased to reduce the impact on the eye.
Color Saturation:
Saturation refers to the purity of any particular color component (Red, Green or Blue).
For example, 100% Red saturation is 100% Red, 0% Green and 0% Blue. No saturation means all the color
percentages are equal. Changes in saturation will change the emphasis of the selected color component.
Contrast:
Contrast is the differentiation between variations of similar colors. Typically contrast is set by
adjusting for best color differentiation between light yellow and white.
Digital Brightness
: This adjustment changes the color of the pixels in the image so they appear brighter.
Adjusting this brightness control may give a more noticeable result than adjusting the backlight brightness.
Frequency:
This adjustment is seldom necessary, but if there is a problem with the frequency of the
monitor pixel clock that it cannot exactly match the clock signal from the camera, an adjustment may be
required. The symptom of a frequency adjustment problem is the appearance of vertical bands in the
image. Adjustment to the frequency setting will help eliminate these artifacts.
Gain (Red, Green, Blue):
Increases in the gain of a color multiplies the proportion of that color in the image
by a factor. The actual amount of additional color is relative to the original level of that color in the image.
Using the two colors mentioned in the Bias description above, if we vary the Gain of the Red by 10% we add
10% of the original color to the original color proportion to get the new color.
Original Color Proportions
Gain Increase
New Color Proportions
Red = 20%
10%
Red = 20% + 0.1 x 20% = 22%
Green = 70%
0%
Green = 70%
Blue = 40%
0%
Blue = 40%
Color Number 2 Proportions
Gain Increase
New Color Proportions
Red = 60%
10%
Red = 60% + 0.1 x 60% = 66%
Green = 40%
0%
Green = 40%
Blue = 30%
0%
Blue = 30%
Notice that the increase in the color proportion of the Red is greater for greater original color proportions of
Red. Lighter reds are increased a lesser amount than darker reds as gain is increased.
Noise Reduction:
Uses a per-pixel motion adaptive algorithm to remove noise from the image while
leaving the image content, motion and detail intact. It also blocks artifacts.
Offset (Red, Green, Blue):
Increasing the offset of a color increases the proportion of that color in the
background of the image.
The level of the selected color is varied equally for all proportions. For example:
Color Number 1 Proportions
Offset Increase
New Color Proportions
Red = 20%
5%
Red = 20% + 5% = 25%
Green = 70%
0%
Green = 70%
Blue = 40%
0%
Blue = 40%
Color Number 2 Proportions
Offset Increase
New Color Proportions
Red = 60%
5%
Red = 60% + 5% = 65%
Green = 40%
0%
Green = 40%
Blue = 30%
0%
Blue = 30%
