Imaging detectors for 10 to 150 keV photons have many uses in medical technology, including tumor imaging, SPECT, and radiography. Digital output is particularly useful since it allows image enhancement, analysis, transmission and storage. In Phase I we proposed a new technology that could capture images with 100 microm spatial resolution and 1 keV energy resolution or better. This capability would facilitate entirely new classes of medical diagnostic procedures, particularly for transgenic small animal imaging. Our Phase I work demonstrated the feasibility of this approach. In this Phase II effort, collaborating with Paul Luke at LBNL, we will construct 1 cm thick crossed-strip HPGe detectors having 10 x 10 strips, each 2 mm x 20 mm. We will develop cooled FET preamplifiers having low noise and large bandwidth properties specifically required by this approach. We will also develop analog filtering electronics to condition the detector's novel signals and employ digital pulse processing electronics to acquire these signals at rates up to 10/6 cps. Finally, we will devise procedures to test the detector's linearity and develop processing algorithms to perfect this quality. Phase II will conclude with a working and tested prototype. Phase III will entail primarily production engineering efforts.
As an energy resolved digital detector with 100 microm spatial resolution, the proposed detector technology could find many medical applications, including SPECT, energy resolved angiography for small mammals, bone densitometry on rodent bones, and small, hand-held gamma cameras. Non-medical applications would include non-destructive testing, astrophysical gamma imaging, nuclear cleanup uses, and x-ray diffraction detectors.
