We present a three-dimensional (3D) tracker for a clinical ophthalmic spectral domain optical coherence tomography (SD-OCT) system that combines depth-tracking with lateral tracking, providing a stabilized reference frame for 3D data recording and post acquisition analysis. The depth-tracking system is implemented through a real-time dynamic feedback mechanism to compensate for motion artifact ...

In this Paper a micro display for an intraocular vision aid (IOVA) projecting an image of the environment onto the retina is presented. The display comprises an image of an array made out of single LED pixels. It is connected to a CMOS driver circuit using flip-chip technique. Since micro lenses have to be integrated into the substrate material for proper image projection onto the retina the ge...

We propose a multimode retina integrating image sensing, normalization, smoothing, differentiation and visual feature extraction by incorporating: 1) a histogram equalization function onto the sensor focal plane, which normalizes the image signal at the same dynamic range under different illumination conditions and results a constant signal amplitude facilitating the post processing; 2) a capac...

With the use of adaptive optics (AO), high-resolution microscopic imaging of living human retina in the single cell level has been achieved. In an adaptive optics confocal scanning laser ophthalmoscope (AOSLO) system, with a small field size (about 1 degree, 280 μm), the motion of the eye severely affects the stabilization of the real-time video images and results in significant distortions of ...

Although biological cells are mostly transparent, they are phase objects that differ in shape and refractive index. Any image that is projected through layers of randomly oriented cells will normally be distorted by refraction, reflection, and scattering. Counterintuitively, the retina of the vertebrate eye is inverted with respect to its optical function and light must pass through several tis...

Retinal prosthesis offers a potential treatment for individuals suffering from photoreceptor degeneration diseases. Establishing biological retinal models and simulating how the biological retina convert incoming light signal into spike trains that can be properly decoded by the brain is a key issue. Some retinal models have been presented, ranking from structural models inspired by the layered...

OBJECTIVE To investigate the cause of the gray appearance of the detached retina. METHODS The effects of ex vivo bovine retinas and Scotch (3M, Minneapolis, Minn) tape on light scattering were predicted based on mathematical modeling and examined empirically on an optical bench. Images were collected with a CCD [charged-coupling device] camera connected to a microcomputer with an image grabbe...

PURPOSE To test the hypothesis that a novel phase-contrast optical coherence tomography (OCT) system can image retinal and choroidal vessels in the living mouse. METHODS A high-speed spectral domain optical coherence tomography (SDOCT) system, which measures the reflections for the entire depth of the retina at once with each axial scan (A-scan), was developed for mouse retinal imaging. Acqui...

Modularity is the main characteristic of the biological systems and especially of the brain 2]. For example , Vision can be described as the interactions of diierent processing systems 1]. Physiologists relate two pathways from the retina. The rst conveys information from the retina to the cortical areas, where specialized areas analyse the visual data (e.g., colour vision, motion detection, ob...