13 October 1986 A One-Megapixel Image Acquisition And Processing System For Solar Oscillation Studies
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As part of the development of a Solar Oscillations Imager (SOI) Experiment for the pro-posed NASA/ESA Solar and Heliospheric Observatory (SOHO) mission a one-megapixel image acquisition and processing system has recently been installed at the Mt. Wilson Observa-tory. This system combines a high-speed CCD camera similar in design to that developed at JPL for the Solar Optical Telescope (SOT) program with a floating-point array processor and a large capacity disk storage subsystem. The CCD camera employs a 1024 x 1024 pixel virtual phase chip manufactured by Texas Instruments. The read-out rate of the camera is approximately 800,000 pixels per second, which means that the entire megapixel array can be read out in slightly more than one second. The JPL-designed camera is interfaced via a custom-design input/output port to a CSPI Mini-MAP floating-point array processor. This array processor currently contains 9 megabytes of memory and hence it can hold two 32-bit floating-point megapixel images at one time in addition to one 8-bit fixed-point image buffer. The array processor is employed to integrate several successive exposures from the CCD camera and to difference selected pairs of these integrated images. The processor can then normalize and calibrate the difference images in real time prior to outputting final images to disk memory at a rate of one calibrated difference picture every minute. The array processor can currently transfer these output images to two 704-megabyte disk drives, which provide sufficient storage capacity to hold one full day's worth (12 hours) of difference images. The stored images can then be archived on tape at 6250 BPI. The entire system is currently employed to record and difference narrowband images of the sun. In this way we can measure the Doppler velocities of the entire visible solar hemisphere once each minute at a spatial resolution of 2 arcseconds. We will describe this system here and show a sample of the images it produces.
© (1986) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Edward J. Rhodes, Edward J. Rhodes, Thomas K. Bursch, Thomas K. Bursch, Roger K. Ulrich, Roger K. Ulrich, Steven Tomczyk, Steven Tomczyk, } "A One-Megapixel Image Acquisition And Processing System For Solar Oscillation Studies", Proc. SPIE 0627, Instrumentation in Astronomy VI, (13 October 1986); doi: 10.1117/12.968098; https://doi.org/10.1117/12.968098


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