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Chapter7Glossary
Chapter 7 Glossary
Clock
The analog signal input monitor needs to reproduce a clock of the same frequency as the dot clock of the
graphics system in use, when the analog signal is converted to a digital signal for image display. This is
called clock adjustment. If the clock pulse is not set correctly, some vertical bars appear on the screen.
DDC/CI (Display Data Channel/Command Interface)
VESA provides the standardization for the interactive communication of the setting information, etc.
between a PC and the monitor.
DVI (Digital Visual Interface)
DVI is a digital interface standard. DVI allows direct transmission of the PC’s digital data without loss.
This adopts the TMDS transmission system and DVI connectors. There are two types of DVI connectors.
One is a DVI-D connector for digital signal input only. The other is a DVI-I connector for both digital and
analog signal inputs.
DVI DMPM (DVI Digital Monitor Power Management)
DVI DMPM is a digital interface power saving function. The “Monitor ON (operating mode)” and “Active
Off (power saving mode)” are indispensable for DVI DMPM as the monitor’s power mode.
Gain
This is used to adjust each color parameter for red, green and blue. An LCD monitor displays the color by
the light passing through the panel color filter. Red, green and blue are the three primary colors. All the
colors on the screen are displayed by combining these three colors. The color tone can be changed by
adjusting the light intensity (volume) passing through each color’s filter.
Gamma
Generally, the monitor brightness varies nonlinearly with the input signal level, which is called “Gamma
Characteristic”. A small gamma value produces a low-contrast image, while a large gamma value produces a
highcontrast image.
HDCP (High-bandwidth Digital Content Protection)
Digital signal coding system developed to copy-protect the digital contents, such as video, music, etc.
This helps to transmit the digital contents safely by coding the digital contents sent via the DVI or HDMI
connector on the output side and decoding them on the input side.
Any digital contents cannot be reproduced if both of the equipments on the output and input sides are not
applicable to HDCP system.
Phase
Phase means the sampling timing to convert the analog input signal to a digital signal. Phase adjustment is
made to adjust the timing. It is recommended that phase adjustment be made after the clock is adjusted
correctly.
