EEV 44-82 -1-A57
CCD name : Ara
Serial number :
9252-12-02
Type : Backside, Single layer AR Pixel size 15x15 µm
Number of photosensitive pixels 2048 x 4102 [HxV]
Number of
outputs : 2
Overall rating :
Test date : 15 Dec 2000
Clock mode: EEV 1p/225k/HG 512 Conversion Factor= 1.085e-/ADU ±0.004 for 23870.2ADU RMS noise = 5.05e- ±0.05 CCD temperature : -120Cº Window area is : X1= 92 X2= 2042 Y1= 9 Y2= 501 Bandwidth 5nm Wav. QE% PRNU rms% Phase= 320 46.3 ±1.3 4.33 7.491919 330 52 ±1.5 4.1 7.427392 340 54.7 ±1.1 3.99 7.394289 350 55.5 ±0.54 4 7.394152 360 57.1 ±0.56 3.99 7.398605 370 60.8 ±0.6 3.56 7.287704 380 68.4 ±0.68 2.55 6.953967 390 75.3 ±0.77 1.88 6.643621 400 78.8 ±0.8 1.51 6.414519 420 81.9 ±0.83 1.19 6.156016 440 83.1 ±0.83 1.08 6.044511 460 82.3 ±0.62 1.03 5.985608 480 81.6 ±0.82 0.957 5.901837 500 81.4 ±0.82 0.944 5.894609 520 81 ±0.81 0.913 5.863371 540 79.8 ±0.8 0.898 5.85503 560 78.4 ±0.78 0.898 5.866243 580 78.1 ±0.78 0.898 5.875317 600 76.8 ±0.76 0.913 5.903675 620 75.9 ±0.75 0.959 5.966185 640 74.6 ±0.73 1.05 6.067703 660 72.4 ±0.7 1.13 6.156096 680 70.4 ±0.67 1.24 6.246556 700 67.4 ±0.63 1.34 6.318153 720 64.8 ±0.6 1.64 6.509082 740 61.7 ±0.56 2 6.675812 760 57.9 ±0.52 2.11 6.749301 780 54.1 ±0.47 2.47 6.851029 800 48.9 ±0.42 2.33 6.84232 840 39.7 ±0.33 2.45 6.886485 900 25.8 ±0.21 3.09 7.141034 940 15.9 ±0.2 4.98 7.612813 1000 4.46 ±0.04 9.19 8.2019 1040 0.709 ±0.006 9.61 8.284498 1100 0.0799 ±0.0006 11.2 8.484301
Table 1: Measurement of the Quantum Efficiency.
Figure 1: Graphic representation of the QE.
Figure 2: Graphic representation of the PRNU.
In this section you can compare the QE we measured with the testbench and
QE Minimum specification
Typical QE
QE from Marconi
Figure 3: Comparison between the QE measured by ESO, the QE measured by Marconi,
ESO specification and minimum specification.
|
Comparison QE ESO / QE Marconi |
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|
Wavelength (nm) |
QE ESO (%) |
QE Marconi (%) |
Difference (Eso - Marc. %) |
Relative difference (Marconi as reference %) |
|
350 |
55.5 |
58.3 |
-2.8 |
-4.8 |
|
400 |
78.8 |
82.1 |
-3.3 |
-4 |
|
500 |
81.4 |
81.2 |
0.2 |
0.2 |
|
650 |
73.5 |
73.8 |
-0.3 |
-0.4 |
|
900 |
25.8 |
28.5 |
-2.7 |
-9.5 |
Table 2: Difference and relative difference between ESO measurement and Marconi.
Figure 4: Graphic representation of the difference and the relative difference.
For the flat field we use three wavelengths, 350nm, 600nm and 900nm. For each wavelength we make two images, high level (45000 ADU) and low level (1000 ADU).
350nm (UV), bandwidth 5nm |
600nm, bandwidth 5nm |
900nm, bandwidth 5nm |
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High level |
Low level |
High level |
Low level |
High level |
Low level |
Table 3: Flat field for three wavelengths.
The time exposure, for the long dark exposure, is 3600 seconds.
|
Bias |
Long exposure dark image |
|---|---|
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Table 4: Bias and dark.
Left Readout port
Clock mode: EEV 1p/50k/HG 512
Conversion Factor= 0.561e-/ADU ±0.002 for 26702.2ADU
RMS noise = 2.4e- ±0.2
Clock mode: 50kpx/4p/HG/512
Right readout port
Conversion Factor= 0.565e-/ADU ±0.003 for 26694.4ADU
RMS noise = 2.5e- ±0.2
Left Readout port
Clock mode: EEV 1p/225k/HG 512
Conversion Factor= 0.544e-/ADU ±0.002 for 26358.4ADU
RMS noise = 5.0e- ±0.3RMS non linearity (%) = 0.221661 Peak to peak non linearity (%)= 0.671232
Figure 5: Error of linearity
Figure 6: Residual non linearity.
Exposure time (s) = 3600 Dark current : 0.15 ± 0.02 e-/hour/pixel
Horizontal CTE = 0.999996 Vertical CTE = 0.9999994
In this section we expose the hot pixel, the dark pixel, the trap and the very large trap we found and how.
Contract: "A very bright pixel provides a signal of > 200000 e- / pixel / hour".
To determine these very bright pixel we add to the pixel all the values above it. If the result is upper to 200000 e- we have a very bright pixel.
Result: No very bright pixel detected.
A hot pixel provides a signal of > 60 e- / pixel / hour. To find them we use a median dark image. We take the median of the image and to find the hot point we add the mean in (e- / pixel / hour) plus the limit (60 e- / pixel / hour). All the pixel which have a value upper than this limits are considered as hot pixel. I repeat this manipulation with two other median filter to confirm the results
Result: 17 hot points.
On our images these points are to the coordinates:
|
Position |
Image |
Histogram around the hot pixel |
X= 1023; Y= 0210 X= 1026; Y= 0210 X= 1028; Y= 0210 X= 1030; Y= 0210 X= 1023; Y= 0211 X= 1024; Y= 0211 X= 1025; Y= 0211 X= 1026; Y= 0211 X= 1027; Y= 0211 X= 1028; Y= 0211 X= 1029; Y= 0211 X= 1030; Y= 0211 |
|
|
X= 0916; Y= 2444 |
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X= 1623; Y= 3510 X= 1624; Y= 3510 |
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X= 0140; Y= 3937 X= 0140; Y= 3938 |
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Table 5: Position and images of the hot pixels. The table values are in ADU. 60 e- = 110 ADU.
A dark pixel is one with 50% or less than the average output for uniform intensity light level, measured with a flat field level around 500 photo-electrons.
Result: No dark pixel detected.
A trap is defined as a pixel that captures more than 10 electrons, measured with a flat field level around 500 photo-electrons.
Result: Not available.
A very large trap is defined as a pixel that captures more than 10 000 electrons, measured with a flat field level around 90% of full well capability.
Result:
On our image (flat600.cpa) this point is to the coordinates:
|
Position |
Image |
Histogram around the very large trap |
|---|---|---|
X= 2010; Y= 1695 X= 2010; Y= 1693 |
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Table6: Position and images of the very large trap.
A bad column is 10 or more contiguous hot or dark pixels in a single column or a very bright pixel or a very large trap.
Result: The very large trap section permits us to determine one bad column to the coordinates X= 2011; Y= 1693.
On the dark image we have also a bright column that we consider as a bad column:
|
Position |
Image |
Histogram around the very large trap |
|---|---|---|
X= 0082; Y= 3585 |
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|
Table7: Position and image of bad columns.
Here is a summary of cosmetic defects:
|
|
Hot pixel |
Dark pixel |
Trap |
Very large trap |
Bad column |
|---|---|---|---|---|---|
|
ESO |
17 |
0 |
/ |
2 |
2 |
|
Marconi |
16 |
1 |
0 |
4 |
|
Table 8: Summary of cosmetic defects.
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