Article

WITHDRAWN: Ultra-high speed burst-mode imager for multi-frame radiography

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Abstract

A 720×720 pixel hybrid-CMOS imager was fabricated by Rockwell Scientific (now Teledyne Imaging Sensors). Several cameras have been in operation for 5 years, in a variety of static and dynamic experiments, at the 800MeV proton radiography (pRAD) facility at the LANSCE accelerator. The cameras can operate with a per-pulse adjustable inter-frame time of 250ns to 2s, and with an exposure/integration-time as short as 150ns. With 80ms total readout time, the imager can be externally synchronized to 0.1–5Hz, 50-ns wide proton beam pulses, and record 1000-frame radiographic movies of 5-to-30min duration. The effectiveness and dependence of the global electronic shutter on the pixelated Si photo-sensor bias voltage is discussed. The spatial resolution dependence of the full imaging system on various monolithic and structured scintillators is presented. We also present features of a new-generation 10-frame, 1024×1024 pixel, 50-ns exposure, 12-bit dynamic range imager, which is now in the design phase.

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... As we demonstrate below, these features lead to far better performance than flash x-rays for thick object flash radiography. A radiograph (Kwiatkowski et al 2010) of the FTO made with a 40 ns long-pulse of 10 11 24 GeV/c protons provided by the alternating gradient accelerator (AGS) at Brookhaven National Laboratory is shown in figure 6. This can be compared with the data x-ray shown in figure 5. ...
... A 720 × 720 pixel hybrid complementary-symmetry metal-oxide-semiconductor (CMOS) imager has been developed to provide higher quantum efficiency by eliminating the photocathode stage in the diode gate in the previous imager (Kwiatkowski et al 2010). These cameras are each capable of storing three frames of data in on-chip capacitive storage. ...
... A new camera under development will provide 10 frames per camera, 1100 × 1100 pixels, a factor of two shorter minimum inter frame time and gate width, and a factor of 3 lower electronic noise (Kwiatkowski et al 2010). This new camera system promises more flexibility in the timing format, lower noise, and more frames. ...
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