VISION THERAPY STARTER SYSTEM (GOOD STARTER KIT) Provides a Large Selection of Products Useful in Testing and Training the Most Common Vision Training Problems
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Stereoscopic Vision, Stereoscope, Selection of Stereo Pair and Its Orientation
International Journal of Science and Research (IJSR) ISSN (Online): 2319-7064 Impact Factor (2012): 3.358 Stereoscopic Vision, Stereoscope, Selection of Stereo Pair and Its Orientation Sunita Devi Research Associate, Haryana Space Application Centre (HARSAC), Department of Science & Technology, Government of Haryana, CCS HAU Campus, Hisar – 125 004, India , Abstract: Stereoscope is to deflect normally converging lines of sight, so that each eye views a different image. For deriving maximum benefit from photographs they are normally studied stereoscopically. Instruments in use today for three dimensional studies of aerial photographs. If instead of looking at the original scene, we observe photos of that scene taken from two different viewpoints, we can under suitable conditions, obtain a three dimensional impression from the two dimensional photos. This impression may be very similar to the impression given by the original scene, but in practice this is rarely so. A pair of photograph taken from two cameras station but covering some common area constitutes and stereoscopic pair which when viewed in a certain manner gives an impression as if a three dimensional model of the common area is being seen. Keywords: Remote Sensing (RS), Aerial Photograph, Pocket or Lens Stereoscope, Mirror Stereoscope. Stereopair, Stere. pair’s orientation 1. Introduction characteristics. Two eyes must see two images, which are only slightly different in angle of view, orientation, colour, A stereoscope is a device for viewing a stereoscopic pair of brightness, shape and size. (Figure: 1) Human eyes, fixed on separate images, depicting left-eye and right-eye views of same object provide two points of observation which are the same scene, as a single three-dimensional image. -
Scalable Multi-View Stereo Camera Array for Real World Real-Time Image Capture and Three-Dimensional Displays
Scalable Multi-view Stereo Camera Array for Real World Real-Time Image Capture and Three-Dimensional Displays Samuel L. Hill B.S. Imaging and Photographic Technology Rochester Institute of Technology, 2000 M.S. Optical Sciences University of Arizona, 2002 Submitted to the Program in Media Arts and Sciences, School of Architecture and Planning in Partial Fulfillment of the Requirements for the Degree of Master of Science in Media Arts and Sciences at the Massachusetts Institute of Technology June 2004 © 2004 Massachusetts Institute of Technology. All Rights Reserved. Signature of Author:<_- Samuel L. Hill Program irlg edia Arts and Sciences May 2004 Certified by: / Dr. V. Michael Bove Jr. Principal Research Scientist Program in Media Arts and Sciences ZA Thesis Supervisor Accepted by: Andrew Lippman Chairperson Department Committee on Graduate Students MASSACHUSETTS INSTITUTE OF TECHNOLOGY Program in Media Arts and Sciences JUN 172 ROTCH LIBRARIES Scalable Multi-view Stereo Camera Array for Real World Real-Time Image Capture and Three-Dimensional Displays Samuel L. Hill Submitted to the Program in Media Arts and Sciences School of Architecture and Planning on May 7, 2004 in Partial Fulfillment of the Requirements for the Degree of Master of Science in Media Arts and Sciences Abstract The number of three-dimensional displays available is escalating and yet the capturing devices for multiple view content are focused on either single camera precision rigs that are limited to stationary objects or the use of synthetically created animations. In this work we will use the existence of inexpensive digital CMOS cameras to explore a multi- image capture paradigm and the gathering of real world real-time data of active and static scenes. -
CS 534: Computer Vision Stereo Imaging Outlines
CS 534 A. Elgammal Rutgers University CS 534: Computer Vision Stereo Imaging Ahmed Elgammal Dept of Computer Science Rutgers University CS 534 – Stereo Imaging - 1 Outlines • Depth Cues • Simple Stereo Geometry • Epipolar Geometry • Stereo correspondence problem • Algorithms CS 534 – Stereo Imaging - 2 1 CS 534 A. Elgammal Rutgers University Recovering the World From Images We know: • 2D Images are projections of 3D world. • A given image point is the projection of any world point on the line of sight • So how can we recover depth information CS 534 – Stereo Imaging - 3 Why to recover depth ? • Recover 3D structure, reconstruct 3D scene model, many computer graphics applications • Visual Robot Navigation • Aerial reconnaissance • Medical applications The Stanford Cart, H. Moravec, 1979. The INRIA Mobile Robot, 1990. CS 534 – Stereo Imaging - 4 2 CS 534 A. Elgammal Rutgers University CS 534 – Stereo Imaging - 5 CS 534 – Stereo Imaging - 6 3 CS 534 A. Elgammal Rutgers University Motion parallax CS 534 – Stereo Imaging - 7 Depth Cues • Monocular Cues – Occlusion – Interposition – Relative height: the object closer to the horizon is perceived as farther away, and the object further from the horizon is perceived as closer. – Familiar size: when an object is familiar to us, our brain compares the perceived size of the object to this expected size and thus acquires information about the distance of the object. – Texture Gradient: all surfaces have a texture, and as the surface goes into the distance, it becomes smoother and finer. – Shadows – Perspective – Focus • Motion Parallax (also Monocular) • Binocular Cues • In computer vision: large research on shape-from-X (should be called depth from X) CS 534 – Stereo Imaging - 8 4 CS 534 A. -
Pediatric Ophthalmology/Strabismus 2017-2019
Academy MOC Essentials® Practicing Ophthalmologists Curriculum 2017–2019 Pediatric Ophthalmology/Strabismus *** Pediatric Ophthalmology/Strabismus 2 © AAO 2017-2019 Practicing Ophthalmologists Curriculum Disclaimer and Limitation of Liability As a service to its members and American Board of Ophthalmology (ABO) diplomates, the American Academy of Ophthalmology has developed the Practicing Ophthalmologists Curriculum (POC) as a tool for members to prepare for the Maintenance of Certification (MOC) -related examinations. The Academy provides this material for educational purposes only. The POC should not be deemed inclusive of all proper methods of care or exclusive of other methods of care reasonably directed at obtaining the best results. The physician must make the ultimate judgment about the propriety of the care of a particular patient in light of all the circumstances presented by that patient. The Academy specifically disclaims any and all liability for injury or other damages of any kind, from negligence or otherwise, for any and all claims that may arise out of the use of any information contained herein. References to certain drugs, instruments, and other products in the POC are made for illustrative purposes only and are not intended to constitute an endorsement of such. Such material may include information on applications that are not considered community standard, that reflect indications not included in approved FDA labeling, or that are approved for use only in restricted research settings. The FDA has stated that it is the responsibility of the physician to determine the FDA status of each drug or device he or she wishes to use, and to use them with appropriate patient consent in compliance with applicable law. -
Stereopsis and Stereoblindness
Exp. Brain Res. 10, 380-388 (1970) Stereopsis and Stereoblindness WHITMAN RICHARDS Department of Psychology, Massachusetts Institute of Technology, Cambridge (USA) Received December 20, 1969 Summary. Psychophysical tests reveal three classes of wide-field disparity detectors in man, responding respectively to crossed (near), uncrossed (far), and zero disparities. The probability of lacking one of these classes of detectors is about 30% which means that 2.7% of the population possess no wide-field stereopsis in one hemisphere. This small percentage corresponds to the probability of squint among adults, suggesting that fusional mechanisms might be disrupted when stereopsis is absent in one hemisphere. Key Words: Stereopsis -- Squint -- Depth perception -- Visual perception Stereopsis was discovered in 1838, when Wheatstone invented the stereoscope. By presenting separate images to each eye, a three dimensional impression could be obtained from two pictures that differed only in the relative horizontal disparities of the components of the picture. Because the impression of depth from the two combined disparate images is unique and clearly not present when viewing each picture alone, the disparity cue to distance is presumably processed and interpreted by the visual system (Ogle, 1962). This conjecture by the psychophysicists has received recent support from microelectrode recordings, which show that a sizeable portion of the binocular units in the visual cortex of the cat are sensitive to horizontal disparities (Barlow et al., 1967; Pettigrew et al., 1968a). Thus, as expected, there in fact appears to be a physiological basis for stereopsis that involves the analysis of spatially disparate retinal signals from each eye. Without such an analysing mechanism, man would be unable to detect horizontal binocular disparities and would be "stereoblind". -
Algorithms for Single Image Random Dot Stereograms
Displaying 3D Images: Algorithms for Single Image Random Dot Stereograms Harold W. Thimbleby,† Stuart Inglis,‡ and Ian H. Witten§* Abstract This paper describes how to generate a single image which, when viewed in the appropriate way, appears to the brain as a 3D scene. The image is a stereogram composed of seemingly random dots. A new, simple and symmetric algorithm for generating such images from a solid model is given, along with the design parameters and their influence on the display. The algorithm improves on previously-described ones in several ways: it is symmetric and hence free from directional (right-to-left or left-to-right) bias, it corrects a slight distortion in the rendering of depth, it removes hidden parts of surfaces, and it also eliminates a type of artifact that we call an “echo”. Random dot stereograms have one remaining problem: difficulty of initial viewing. If a computer screen rather than paper is used for output, the problem can be ameliorated by shimmering, or time-multiplexing of pixel values. We also describe a simple computational technique for determining what is present in a stereogram so that, if viewing is difficult, one can ascertain what to look for. Keywords: Single image random dot stereograms, SIRDS, autostereograms, stereoscopic pictures, optical illusions † Department of Psychology, University of Stirling, Stirling, Scotland. Phone (+44) 786–467679; fax 786–467641; email [email protected] ‡ Department of Computer Science, University of Waikato, Hamilton, New Zealand. Phone (+64 7) 856–2889; fax 838–4155; email [email protected]. § Department of Computer Science, University of Waikato, Hamilton, New Zealand. -
Stereoscopic Therapy: Fun Or Remedy?
STEREOSCOPIC THERAPY: FUN OR REMEDY? SARA RAPOSO Abstract (INDEPENDENT SCHOLAR , PORTUGAL ) Once the material of playful gatherings, stereoscop ic photographs of cities, the moon, landscapes and fashion scenes are now cherished collectors’ items that keep on inspiring new generations of enthusiasts. Nevertheless, for a stereoblind observer, a stereoscopic photograph will merely be two similar images placed side by side. The perspective created by stereoscop ic fusion can only be experienced by those who have binocular vision, or stereopsis. There are several caus es of a lack of stereopsis. They include eye disorders such as strabismus with double vision. Interestingly, stereoscopy can be used as a therapy for that con dition. This paper approaches this kind of therapy through the exploration of North American collections of stereoscopic charts that were used for diagnosis and training purposes until recently. Keywords. binocular vision; strabismus; amblyopia; ste- reoscopic therapy; optometry. 48 1. Binocular vision and stone (18021875), which “seem to have access to the visual system at the same stereopsis escaped the attention of every philos time and form a unitary visual impres opher and artist” allowed the invention sion. According to the suppression the Vision and the process of forming im of a “simple instrument” (Wheatstone, ory, both similar and dissimilar images ages, is an issue that has challenged 1838): the stereoscope. Using pictures from the two eyes engage in alternat the most curious minds from the time of as a tool for his study (Figure 1) and in ing suppression at a low level of visual Aristotle and Euclid to the present day. -
Binocular Vision
Published by Jitendar P Vij Jaypee Brothers Medical Publishers (P) Ltd Corporate Office 4838/24 Ansari Road, Daryaganj, New Delhi -110002, India, Phone: +91-11-43574357. Fax: +91-11-43574314 Registered Office B-3 EMCA House. 23'23B Ansari Road, Daryaganj. New Delhi -110 002, India Phones: +91-11-23272143, +91-11-23272703, +91-11-23282021 +91-11-23245672, Rel: +91-11-32558559, Fax: +91-11-23276490, +91-11-23245683 e-mail: [email protected], Website: www.jaypeebro1hers.com O ffices in India • Ahmedabad. Phone: Rel: +91 -79-32988717, e-mail: [email protected] • Bengaluru, Phone: Rel: +91-80-32714073. e-mail: [email protected] • Chennai, Phone: Rel: +91-44-32972089, e-mail: [email protected] • Hyderabad, Phone: Rel:+91 -40-32940929. e-mail: [email protected] • Kochi, Phone: +91 -484-2395740, e-mail: [email protected] • Kolkata, Phone: +91-33-22276415, e-mail: [email protected] • Lucknow. Phone: +91 -522-3040554. e-mail: [email protected] • Mumbai, Phone: Rel: +91-22-32926896, e-mail: [email protected] • Nagpur. Phone: Rel: +91-712-3245220, e-mail: [email protected] Overseas Offices • North America Office, USA, Ph: 001-636-6279734, e-mail: [email protected], [email protected] • Central America Office, Panama City, Panama, Ph: 001-507-317-0160. e-mail: [email protected] Website: www.jphmedical.com • Europe Office, UK, Ph: +44 (0)2031708910, e-mail: [email protected] Surgical Techniques in Ophthalmology (Strabismus Surgery) ©2010, Jaypee Brothers Medical Publishers (P) Ltd. All rights reserved. No part of this publication should be reproduced, stored in a retrieval system, or transmitted in any form or by any means: electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the editors and the publisher. -
Does Occlusion Therapy Improve Control in Non-Diplopic Patients with Intermittent Exotropia?
Does Occlusion Therapy Improve Control in Non-Diplopic Patients with Intermittent Exotropia? by Lina Sulaiman Alkahmous Submitted in partial fulfilment of the requirements for the degree of Master of Science at Dalhousie University Halifax, Nova Scotia November 2011 © Copyright by Lina Sulaiman Alkahmous, 2011 DALHOUSIE UNIVERSITY CLINICAL VISION SCIENCE PROGRAM The undersigned hereby certify that they have read and recommend to the Faculty of Graduate Studies for acceptance a thesis entitled “Does Occlusion Therapy Improve Control in Non-Diplopic Patients with Intermittent Exotropia?” by Lina Sulaiman Alkahmous in partial fulfilment of the requirements for the degree of Master of Science. Dated: November 17, 2011 Supervisors: _________________________________ _________________________________ Readers: _________________________________ _________________________________ _________________________________ ii DALHOUSIE UNIVERSITY DATE: November 17, 2011 AUTHOR: Lina Sulaiman Alkahmous TITLE: Does Occlusion Therapy Improve Control in Non-Diplopic Patients with Intermittent Exotropia? DEPARTMENT OR SCHOOL: Clinical Vision Science Program DEGREE: MSc CONVOCATION: May YEAR: 2012 Permission is herewith granted to Dalhousie University to circulate and to have copied for non-commercial purposes, at its discretion, the above title upon the request of individuals or institutions. I understand that my thesis will be electronically available to the public. The author reserves other publication rights, and neither the thesis nor extensive extracts from -
Chromostereo.Pdf
ChromoStereoscopic Rendering for Trichromatic Displays Le¨ıla Schemali1;2 Elmar Eisemann3 1Telecom ParisTech CNRS LTCI 2XtremViz 3Delft University of Technology Figure 1: ChromaDepth R glasses act like a prism that disperses incoming light and induces a differing depth perception for different light wavelengths. As most displays are limited to mixing three primaries (RGB), the depth effect can be significantly reduced, when using the usual mapping of depth to hue. Our red to white to blue mapping and shading cues achieve a significant improvement. Abstract The chromostereopsis phenomenom leads to a differing depth per- ception of different color hues, e.g., red is perceived slightly in front of blue. In chromostereoscopic rendering 2D images are produced that encode depth in color. While the natural chromostereopsis of our human visual system is rather low, it can be enhanced via ChromaDepth R glasses, which induce chromatic aberrations in one Figure 2: Chromostereopsis can be due to: (a) longitunal chro- eye by refracting light of different wavelengths differently, hereby matic aberration, focus of blue shifts forward with respect to red, offsetting the projected position slightly in one eye. Although, it or (b) transverse chromatic aberration, blue shifts further toward might seem natural to map depth linearly to hue, which was also the the nasal part of the retina than red. (c) Shift in position leads to a basis of previous solutions, we demonstrate that such a mapping re- depth impression. duces the stereoscopic effect when using standard trichromatic dis- plays or printing systems. We propose an algorithm, which enables an improved stereoscopic experience with reduced artifacts. -
Binocular Vision
BINOCULAR VISION Rahul Bhola, MD Pediatric Ophthalmology Fellow The University of Iowa Department of Ophthalmology & Visual Sciences posted Jan. 18, 2006, updated Jan. 23, 2006 Binocular vision is one of the hallmarks of the human race that has bestowed on it the supremacy in the hierarchy of the animal kingdom. It is an asset with normal alignment of the two eyes, but becomes a liability when the alignment is lost. Binocular Single Vision may be defined as the state of simultaneous vision, which is achieved by the coordinated use of both eyes, so that separate and slightly dissimilar images arising in each eye are appreciated as a single image by the process of fusion. Thus binocular vision implies fusion, the blending of sight from the two eyes to form a single percept. Binocular Single Vision can be: 1. Normal – Binocular Single vision can be classified as normal when it is bifoveal and there is no manifest deviation. 2. Anomalous - Binocular Single vision is anomalous when the images of the fixated object are projected from the fovea of one eye and an extrafoveal area of the other eye i.e. when the visual direction of the retinal elements has changed. A small manifest strabismus is therefore always present in anomalous Binocular Single vision. Normal Binocular Single vision requires: 1. Clear Visual Axis leading to a reasonably clear vision in both eyes 2. The ability of the retino-cortical elements to function in association with each other to promote the fusion of two slightly dissimilar images i.e. Sensory fusion. 3. The precise co-ordination of the two eyes for all direction of gazes, so that corresponding retino-cortical element are placed in a position to deal with two images i.e. -
Student V.T. Manual
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CommonKnowledge Pacific University CommonKnowledge College of Optometry Theses, Dissertations and Capstone Projects 1982 Student V.T. manual Craig Cutler Pacific University Colleen Schubach Pacific University Recommended Citation Cutler, Craig and Schubach, Colleen, "Student V.T. manual" (1982). College of Optometry. 630. https://commons.pacificu.edu/opt/630 This Thesis is brought to you for free and open access by the Theses, Dissertations and Capstone Projects at CommonKnowledge. It has been accepted for inclusion in College of Optometry by an authorized administrator of CommonKnowledge. For more information, please contact [email protected]. Student V.T. manual Abstract Student V.T. manual Degree Type Thesis Degree Name Master of Science in Vision Science Committee Chair Rocky Kaplan Subject Categories Optometry This thesis is available at CommonKnowledge: https://commons.pacificu.edu/opt/630 Copyright and terms of use If you have downloaded this document directly from the web or from CommonKnowledge, see the “Rights” section on the previous page for the terms of use. If you have received this document through an interlibrary loan/document delivery service, the following terms of use apply: Copyright in this work is held by the author(s). You may download or print any portion of this document for personal use only, or for any use that is allowed by fair use (Title 17, §107 U.S.C.). Except for personal or fair use, you or your borrowing library may not reproduce, remix, republish, post, transmit, or distribute this document, or any portion thereof, without the permission of the copyright owner.