Laboratory Device For Demonstrating Medical Imaging In The Classroom

In this paper, we describe the details of the experimental setup developed with the objective of demonstrating the principles of tomography using visible light. Most tomographic methods use invisible forms of radiation (e.g., x-rays or ultrasound) and therefore it is not very instructive to see them in operation. The proposed setup consists of a translucent object illuminated by a simple white-light source and imaged with the digital camera at different angles. Collimation is provided by using a readily available telecentric lens to perform the imaging. This eliminates the need for a collimated light source, which can increase the cost of the system, and which usually involves hazardous sources such as lasers or laser diodes. By using visible light, students can observe the whole process directly. The students can control the image acquisition parameters and observe the reconstruction process on a computer. In this paper we focus on providing detailed design information so that the experimental setup can be reproduced by interested educators. A separate paper [3] discusses the educational issues relating to the proposed experiment including assessment results.