Functionality of the curvature CCD

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  • 80 integration areas
  • High quantum efficiency (peak greater 80 %)
  • Very short exposure times (250 µs) with "long" integration times (1 to 20 ms, 2 to 40 cyclesof a 2 kHz membrane)
  • Abitlity to switch between half-cycle integrations within 10 µs
  • Ability to store half-cycle frames on-chip while integrating other half-cycle frames
  • Read out of all pixels within 250 µs
  • Use of superpixels i.e. bin on-chip to loosen alignment tolerances
  • Use of multiple read out ports to have slower read out rates and lower read out noise
 CCID 35
CCD image (0 s exposure) in unbinned mode
CCD image in unbinned mode (dark frame) This image shows a dark frame of the CCID-35 in unbinned mode.

Per read out port 20 image and 4 overscan pixels are read out in the vertical direction and 200 image pixels and 10 overscan pixels in the horizontal direction.

Note that the serial registers are in horizontal direction in this image.
CCD image in unbinned mode showing the 60 fiber spots
CCD image in unbinned mode (60 fiber spots) This image shows an exposure frame of the CCID-35 in unbinned mode showing the 60 fiber spots.

Per read out port 20 image and 4 overscan pixels are read out in the vertical direction and 200 image pixels and 10 overscan pixels in the horizontal direction.

Note that the serial registers are in horizontal direction in this image.
CCD image in unbinned mode showing photons stored in the storage pixels   SA   and   SB
CCD image in unbinned mode with storage pixels This image shows an CCID-35 image with charge collected during extrafocal and intrafocal periods of 10 cycles and stored in storage pixels   SA   and   SB.

Note that this requires charge movement up and down in vertical direction.

Note that the serial registers are in horizontal direction in this image.
CCD image in 20 x 20 binned mode showing photons stored in the storage pixels   SA   and   SB
CCD image in 20 x 20 binned mode with storage pixels This image shows an CCID-35 image in curvature mode (20 x 20 binning). Charge is colleced during extrafocal and intrafocal periods of 10 cycles and stored in storage pixels   SA   and   SB   and then read out.

Each superpixel reflects one subaperture in this mode. However for better visualisation parallels are overscanned by two superpixels.

Note that this requires charge movement up and down in vertical direction.

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Last update:   Jan 27, 2003
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