Chapter 5
5-16
The output of the CCD may not necessarily be even because of the following factors even if the density of the original is perfectly even:
(1) variation in the sensitivity of the individual pixels of the CCD
(2) difference in the degree of light passing through the center of the lens and through its edge
(3) difference in the intensity of light between the center and ends of the scanning lamp
(4) deterioration of the scanning lamp
The machine executes shading correction to make up for the variation in the output of the CCD.
Shading correction may be shading adjustment executed to determine a service mode target value or shading correction executed for every job.
5.3.6.6 Shading Adjustment
0015-4418
iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N
In shading adjustment, the machine measures the density of a white sheet of paper and the standard white plate, and stores the measurements in memory. The ma-
chine then computes these measurements for use as the target value for shading correction. Shading adjustment is executed at time of machine installation or scan-
ning lamp replacement, or when a change has occurred in the intensity of light over time.
Service Mode:
COPIER>FUNCTION>CCD>CCD-ADJ
5.3.6.7 Shading Correction
0015-4420
iR5065 / iR 5055 / iR5075 / iR5075N / iR5065N / iR5055N
The machine executes shading correction for every scan of an original.
The machine shines the light of the scanning lamp against the standard white plate, and measures the light reflected by the plate; it then uses the analog image
processing block of the CCD/AP PCB to turn the measurements into digital data, which will be sent to the shading correction circuit of the reader controller PCB
in the form of a shading coefficient.
In the shading correction circuit, the shading coefficient is compared against the target value stored in memory, and the machine uses the differences as the shading
correction value.
The shading correction value is used to make up for the variation among individual pixels of the CCD occurring at each scan, thus evening out the image density
level.
F-5-34
CCD output
Original density
Standard white plate
Characteristics before
correction
Target value
Measurement
Characteristics after
correction
White
Summary of Contents for iR5055
Page 1: ...Feb 29 2008 Service Manual iR5075 5065 5055 Series ...
Page 2: ......
Page 6: ......
Page 27: ...Contents 19 1 2 List of Solvents Oils 19 2 ...
Page 28: ...Contents ...
Page 29: ...Chapter 1 Introduction ...
Page 30: ......
Page 32: ......
Page 59: ...Chapter 2 Installation ...
Page 60: ......
Page 104: ...Chapter 2 2 42 F 2 156 2 1 ...
Page 105: ...Chapter 3 Basic Operation ...
Page 106: ......
Page 108: ......
Page 115: ...Chapter 4 Main Controller ...
Page 116: ......
Page 118: ......
Page 135: ...Chapter 5 Original Exposure System ...
Page 136: ......
Page 169: ...Chapter 6 Laser Exposure ...
Page 170: ......
Page 172: ......
Page 178: ......
Page 179: ...Chapter 7 Image Formation ...
Page 180: ......
Page 184: ......
Page 217: ...Chapter 8 Pickup Feeding System ...
Page 218: ......
Page 274: ......
Page 275: ...Chapter 9 Fixing System ...
Page 276: ......
Page 280: ......
Page 320: ......
Page 321: ...Chapter 10 External and Controls ...
Page 322: ......
Page 326: ......
Page 336: ...Chapter 10 10 10 F 10 7 2 Remove the check mark from SNMP Status Enabled ...
Page 337: ...Chapter 10 10 11 F 10 8 ...
Page 361: ...Chapter 11 MEAP ...
Page 362: ......
Page 364: ......
Page 409: ...Chapter 12 e maintenance imageWARE Remote ...
Page 410: ......
Page 412: ......
Page 421: ...Chapter 13 Maintenance and Inspection ...
Page 422: ......
Page 424: ......
Page 433: ...Chapter 14 Standards and Adjustments ...
Page 434: ......
Page 464: ......
Page 465: ...Chapter 15 Correcting Faulty Images ...
Page 466: ......
Page 468: ......
Page 496: ......
Page 497: ...Chapter 16 Self Diagnosis ...
Page 498: ......
Page 500: ......
Page 528: ......
Page 529: ...Chapter 17 Service Mode ...
Page 530: ......
Page 532: ......
Page 600: ......
Page 601: ...Chapter 18 Upgrading ...
Page 602: ......
Page 604: ......
Page 636: ...Chapter 18 18 32 F 18 59 2 Select the data to download F 18 60 3 Click Start ...
Page 638: ......
Page 639: ...Chapter 19 Service Tools ...
Page 640: ......
Page 642: ......
Page 645: ...Feb 29 2008 ...
Page 646: ......