Srgb Adjustment Procedures - NEC MultiSync LCD2080UX -BKA Service Manual

3.7.4 sRGB Adjustment Procedures

The adjustment procedures shown below should be applied only if an accurate adjustment of sRGB
is called for.
There is no problem in actual use of equipment so long as the items 3.7.1 to 3.7.3 described above
are usually executed.
a. EEPROM (IC803) initialization
1) When a PWB is replaced with a maintenance PWB, the items 3.7.1 to 3.7.3 described above are
executed.
2) When the EEPROM (IC803) is replaced, the items 3.7.1 to 3.7.3 described above are executed.
3) In the service menu of "tab F," confirm that each EEPROM address is given by a value specified in
Table 1.
If any discrepancy is discovered, correct the address values. (In regard to the method of adjustment,
refer to Item 3, Service menu in Chapter 5, Circuit Descriptions.)
Caution: The adjustment signal should be used at a definition of 1600 x 1200, 60Hz.
b. White balance data initialization
1) In the service menu of "tab F," confirm that each EEPROM address is given by a value specified in
Table 2.
If any discrepancy is discovered, correct the address values. (In regard to the method of adjustment,
refer to Item 3, Service menu in Chapter 5, Circuit Descriptions.)
c. sRGB 51 parameter setting
1) In the service mode of "sRGB," confirm that each table is given as specified in Table 3.
If any discrepancy is discovered, correct the table values. (In regard to the method of adjustment, refer
to Item 3, Service menu in Chapter 5, Circuit Descriptions.)
d. White balance manual adjustment
1) Enter signals (all white, UXGA, 60Hz, 0.7Vpp) and execute [tab 3] → [AUTO CONTRAST] of the
service menu.
2) Select [RGB (AccuColor Control Systems)] of the service menu.
3) Select 1 (9300K).
4) Set the display of color temperature at 5000K with the use of the (+) or (-) keys.
5) Using the color analyzer CA110 (or equivalent), measure the color temperature. Confirm that the color
temperature is set at the xy value of 5000K as specified in Table 4.
6) Using the (+) or (-) keys, set the display of the color temperature at 5000K, 6500K, 7500K, 8500K, and
9600K, and confirm that each color temperature is set at the xy value as specified in Table 4.
7) If each xy value is found deviating from the value specified in Table 4, set the correct value again by
rewriting the white balance data of the EEPROM. The data modified with [tab F] of the service menu
can be reflected by the action of unit power supply OFF → ON.
Cautions: 1) About 30 minutes of heat run is required when measuring the values with a color analyzer.
2) During measurements, the panel surface should not be exposed to external light so long as
circumstances permit.
3) Some color analyzers are designed to permit the direct readout of color temperatures.
However, these devices are often incapable of displaying deviations from the black body
locus (mpcd). Checks and adjustments are required on the basis of the x-y coordinates.
4) The default values of the user menu are 8200K and 9300K. For the checks and adjustments,
however, this setting should be made at 8500K and 9600K.
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