Law of refraction for generalised confocal lenslet arrays

We derive the law of generalised refraction for generalised confocal lenslet arrays, which are arrays of misaligned telescopes. We have implemented this law of refraction in TIM, a custom open-source ray tracer.Comment: 4 pages, 3 figure

Lorentz-transformation and Galileo-transformation Windows

We define Lorentz-transformation windows as windows that change the direction of transmitted light rays like a Lorentz transformation. Similarly, Galileo-transformation windows change the direction of transmitted light rays like a Galileo transformation. This light-ray-direction change distorts the scene seen through such a window in the same way in which the scene would be distorted in a photo taken with a camera moving through the scene. Lorentz-transformation windows can also undo the distortion of the scene when moving at relativistic velocity relative to it. For small angles between the direction of the light rays and the direction of the velocity, Galileo-transformation windows can be realised with relatively simple telescope windows, which consist of arrays of identical micro-telescopes

Complex Imaging with Ray-rotating Windows

We study the imaging properties of windows that rotate the direction of transmitted light rays by a fixed angle around the window normal [A. C. Hamilton et al., J. Opt. A: Pure Appl. Opt. 11,085705 (2009)]. We previously found that such windows image between object and image positions with suitably defined complex longitudinal coordinates [J. Courtial et al., Opt. Lett. 37, 701 (2012)]. Here we extend this work to object and image positions in which any coordinate can be complex. This is possible by generalising our definition of what it means for alight ray to pass through a complex position: the vector from the real part of the position to the point on the ray that is closest to that real part of the position must equal the cross product of the imaginary part of the image position and the normalised light-ray-direction vector. In the paraxial limit, we derive the equivalent of the lens equation for planar and spherical ray-rotating windows. These results allow us to describe complex imaging in more general situations, involving combinations of lenses and inclined ray-rotating windows. We illustrate our results with ray-tracing simulations

Perfect imaging with planar interfaces

We describe the most general homogenous, planar, light-ray-direction-changing sheet that performs one-to-one imaging between object space and image space. This is a nontrivial special case (of the sheet being homogenous) of an earlier result [Opt. Commun. 282, 2480 (2009)]. Such a sheet can be realized, approximately, with generalized confocal lenslet arrays

Relativistic photography with a wide aperture

We discuss new effects related to relativistic aberration, which is the apparent distortion of objects moving at relativistic speeds relative to an idealized camera. Our analysis assumes that the camera lens is capable of stigmatic imaging of objects at rest with respect to the camera, and that each point on the shutter surface is transparent for one instant, but different points are not necessarily transparent synchronously. We pay special attention to the placement of the shutter. First, we find that a wide aperture requires the shutter to be placed in the detector plane to enable stigmatic images. Second, a Lorentz-transformation window [Proc. SPIE 9193, 91931K (2014) [CrossRef] ] can correct for relativistic distortion. We illustrate our results, which are significant for future spaceships, with raytracing simulations

Applications of single-pixel imaging

In this body of work, several single-pixel imaging applications are presented, based on structured light manipulation via a Digital Micromirror Device (DMD) and a single element photodetector (PD). This is commonly known as computational single-pixel imaging, and is achieved by using the measurements made by the PD to weight a series of projected structured light-fields. This indicates the strength of correlation between each light-field, and some object or scene placed in its propagation path. After many iterations the ensemble average of the weighted structured light-field converges to the object. Historically, computational single-pixel imaging has suffered from long image acquisition times and low resolution. Inhibiting the ability of physical systems from competing with conventional imaging in any form. Advances in computer and DMD technology have opened new avenues of research for this novel imaging technique. These advances have been utilised in this work by creating fast acquisition demonstrator systems, which have real world applications, such as multi-wavelength, polarisation, and long-range imaging. Several PDs were added to allow for simultaneous measurement of multiple images in the desired application. For multi-wavelength, RGB and white light illumination was spectrally filtered on three detectors to create full-colour images. While conversely the same multi-detector approach allowed for simultaneous measurement of orthogonal linear polarisation states essential to Stokes' parameter image reconstruction. Differential projection of the structured light-fields further allowed for the single-pixel camera to compensate from some sources of real world noise, such as background illumination. This work demonstrates an evolution of the single-pixel camera. From a system capable of only imaging simple, binary transmissive objects twice per hour and constrained to an optical bench, to a semi portable camera, capable of multiple frames per second 2D reconstructions of 3D scenes over a range of 20 kilometres. These improvements in capability cement the idea that the single-pixel camera is now a viable alternate imaging technology

TIM, a ray-tracing program for METATOY research and its dissemination

This program has been imported from the CPC Program Library held at Queen's University Belfast (1969-2018) Abstract TIM (The Interactive METATOY) is a ray-tracing program specifically tailored towards our research in METATOYs, which are optical components that appear to be able to create wave-optically forbidden light-ray fields. For this reason, TIM possesses features not found in other ray-tracing programs. TIM can either be used interactively or by modifying the openly available source code; in both cases, it can easily be run as an applet embedded in a web page. Here we describe the basic structure of ... Title of program: TIM Catalogue Id: AEKY_v1_0 Nature of problem Visualisation of scenes that include scene objects that create wave-optically forbidden light-ray fields. Versions of this program held in the CPC repository in Mendeley Data AEKY_v1_0; TIM; 10.1016/j.cpc.2011.11.011 AEKY_v2_0; TIM; 10.1016/j.cpc.2013.10.03