KAI−04070
TEST DEFINITIONS
Test Regions of Interest
Overclocking
The test system timing is configured such that the sensor
is overclocked in both the vertical and horizontal directions.
See Figure 22 for a pictorial representation of the regions of
interest.
Image Area ROI: Pixel (1, 1) to Pixel (2080, 2080)
Active Area ROI: Pixel (17, 17) to Pixel (2064, 2064)
Center ROI:
Pixel (991, 991) to Pixel (1090, 1090)
Only the Active Area ROI pixels are used for performance
and defect tests.
16 Dark Rows
16 Buffer Rows
2048 × 2048
Active Pixels
Pixel
17,
17
Pixel
1, 1
16 Buffer Rows
16 Dark Rows
VOUTa
Figure 22. Regions of Interest
Tests
Dark Field Global Non-Uniformity
are found. The dark field global uniformity is then calculated
as the maximum signal found minus the minimum signal
level found.
This test is performed under dark field conditions.
The sensor is partitioned into 256 sub regions of interest,
each of which is 128 by 128 pixels in size. The average signal
level of each of the 256 sub regions of interest is calculated.
The signal level of each of the sub regions of interest is
calculated using the following formula:
Global Non-Uniformity
This test is performed with the imager illuminated to
a level such that the output is at 70% of saturation
(approximately 924 mV). Prior to this test being performed
the substrate voltage has been set such that the charge
capacity of the sensor is 1,320 mV. Global non-uniformity
is defined as
Signal of ROI[i] + (ROI Average in Counts *
* Horizontal Overclock Average in Counts) @
@ mV per Count
Active Area Standard Deviation
Global Non−Uniformity + 100 @ ǒ
Ǔ
Units : mVpp (millivolts Peak to Peak)
Active Area Signal
Units : % rms
Active Area Signal = Active Area Average − Dark Column Average
where i = 1 to 256. During this calculation on the 256 sub
regions of interest, the maximum and minimum signal levels
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