Uniformly redundant arrays (URA) have autocorrelation functions with perfectly flat sidelobes. The URA combines the high-transmission characteristics of the random array with the flat sidelobe advantage of the nonredundant pinhole arrays. A general expression for the signal-to-noise ratio (SNR) has been developed for the URA as a function of the type of object being imaged and the design parame...

We show that it is possible to find and characterise optical vortices in a speckle pattern using a multi-pinhole interferometer. This measurement does not require an interferometric setup, providing great experimental ease. In addition, a multi-pinhole interferometer can be made arbitrarily large and can therefore be adjusted to the expected speckle size. We present experimental results confirm...

This paper describes an efficient method of generating a model-based system matrix using Monte Carlo simulation for incorporation into reconstruction algorithms for pinhole SPECT imaging and reconstructions. The method is able to model the imaging geometry for pinhole collimators and the detector depth of interaction effect accurately and efficiently, and has demonstrated improvement in the qua...

ception, and cognitive courses, as well as introductory courses, and can implement the demonstration in lecture or in a laboratory assignment in which students manipulate the lens and screen themselves. Instructors may even assign the construction of a classroom-sized or traditional-sized pinhole camera as a class project. Regardless of how instructors choose to use it, we conclude that the pin...

BACKGROUND A prototype anthropomorphic head and neck phantom has been designed to simulate the adult head and neck anatomy including some internal organs and tissues of interest, such as thyroid gland and sentinel lymph nodes (SLNs). The design of the head and neck phantom includes an inner jig holding the simulated SLNs and thyroid gland. The thyroid gland structure was manufactured using thre...

A very important property of the usual pinhole model for camera projection is that 3D lines in the scene are projected to 2D lines. Unfortunately, wide-angle lenses (specially low-cost lenses) may introduce a strong barrel distortion, which makes the usual pinhole model fail. Lens distortion models try to correct such distortion. In reference 1., we propose an algebraic approach to the estimati...