Red-ray computed tomography with high spatial resolutions

Abstract

To image blood vessels, we performed fundamental experiments of a red-ray computed tomography (RRCT) scanner using 650-nm-laser and high-sensitivity-photodiode (PD) modules. The line laser beam is irradiated to an object, and the photons penetrating through the object are detected using the PD module through a 1.0-mm-diameter graphite pinhole and a 0.7-mm-diameter 5-mm-length graphite collimator for the PD. The spatial resolutions were primarily determined by the collimator diameter for the PD and were approximately 0.7×0.7 mm2. RRCT was performed by repeating the reciprocating translations and rotations of the object, and the ray-sampling-translation and rotation steps were 0.1 mm and 0.5°, respectively. The image contrast was regulated using the digital amplifier, and the visible diameter of object was 0.5mm.