BACKGROUND Small animal imaging has recently been the subject of increasing interest and specific imaging devices in particular for positron emission tomography (PET) have been developed. To bypass limitations arising from high acquisition costs and dependence on an in-house cyclotron unit inevitably associated with PET, a conventional gamma camera has been equipped with a pinhole collimator an...

Pinhole SPECT for small animal has become a routine procedure in many applications of molecular biology and pharmaceutical development. There is an increasing demand in the whole body imaging of lab animals. A simple and direct solution is to scan the object along a helical trajectory, similar to a helical CT scan. The corresponding acquisition time can be greatly reduced, while the over-lappin...

The Crossed-Slits (X-Slits) camera is defined by two nonintersecting slits, which replace the pinhole in the common perspective camera. Each point in space is projected to the image plane by a ray which passes through the point and the two slits. The X-Slits projection model includes the pushbroom camera as a special case. In addition, it describes a certain class of panoramic images, which are...

STT-MRAM mass production is around the corner as major foundries worldwide invest heavily on its commercialization. To ensure high-quality products, effective yet cost-efficient test solutions are of great importance. This article presents a systematic device-aware defect and fault modeling framework for to derive accurate models which reflect physical defects appropriately, thereafter optimal ...

We report on a novel diagnostics instrument for in-situ imaging and measurements of X-ray beam parameters in real-time. The instrument is based on the robust and simple idea of a pinhole camera that collects the weakly scattered radiation from a thin sheet of a low-Z material placed in the X-ray beam at an acute angle. We demonstrate how by recording the scattered radiation with an appropriate ...

We identify and study two types of “accidental” images that can be formed in scenes. The first is an accidental pinhole camera image. The second class of accidental images are “inverse” pinhole camera images, formed by subtracting an image with a small occluder present from a reference image without the occluder. Both types of accidental cameras happen in a variety of different situations. For ...

The majority of computer vision applications assumes that the camera adheres to the pinhole camera model. However, most optical systems will introduce undesirable effects. By far, the most evident of these effects is radial lensing, which is particularly noticeable in fish-eye camera systems, where the effect is relatively extreme. Several authors have developed models of fish-eye lenses that c...

In this paper we use a simple, active-camera model to estimate the time-to-contact (TTC) of a moving object. We estimate TTC by enforcing a \uniform scale" constraint on the moving object. By actively adjusting the focal length of the pinhole model, the projected object maintains a xed image scale regardless of its motion. These adjustments on the ideal pinhole focal length are translated into ...

An improved tomographic algorithm in the scheme of Tikhonov-Phillips regularisation method, has been employed for multi-pixel bolometric measurements in order to get as much information as possible while keeping the assumptions to a minimum. The effects of finite detector size have been taken into account with a full three dimensional treatment of the detector geometry. The application of tomog...

Coherent diffraction microscopy requires a well-defined illumination wave such as a plane wave on a specimen. Experimentally, a small pinhole or a focused beam is often used to reduce the illumination area but they unavoidably distort the waves. The distortion of the illumination wave causes artifacts in the phase retrieval of oversampled diffraction patterns. Using computer simulations, we sea...