Index Matching CAT Scan

Computerized tomography (CT) scans are based on interesting X-ray physics, but due to their bulk, cost and safety, hands on experience with an X-ray based scanner is unrealistic for undergraduate students. This project details the development of a small, novel, safe and inexpensive CT scanner. The experimental set-up presented utilizes visible light, has short data acquisition time and operates on the same physics as it's X-ray counterpart. The apparatus employs microcontrolled stepper-motors, a laser and photo-diode to image a transparent material submerged in a matching index of refraction liquid. A simple back-projection algorithm results in a 2-D cross section of the object. Data can be collected and image reconstructed in under 15 minutes.