(Left) Illustration of the source of parallax errors in pinhole gamma camera. (Right) Laser pixelated scintillator for use with pinhole SPECT camera with the pixels focused towards the pinhole in order to minimize parallax errors.
RMD has developed a technique for laser pixelation of scintillator to fabricate structured scintillators for specific imaging applications. For example, the spatial resolution in small animal pinhole SPECT cameras is limited by parallax errors in the scintillator, particularly towards the edge of the field of view. We can overcome these errors using a focused cut scintillator.
Scanning electron microscope micrographs of an RMD injected-capillary plastic scintillator.
Scintillator injection techniques enable us to inject scintillator materials (such as CsI-based, NaI-based and plastic scintillators) into fine capillary arrays for high resolution, high efficiency gamma-ray imaging and neutron detection.
The capillaries may be parallel, with uniform diameter, or may be focused on a point or region in space in front of or behind the scintillator structure, with uniform or varying diameter. This structure eliminates optical crosstalk between neighboring pixels, thereby resulting in high spatial resolution, regardless of sensor thickness. Capillary diameters may vary from 25 microns to over 2 mm, depending on the resolution requirement and the material to be injected. This process is suitable for alkali halide and plastic scintillators.