A Geometric Model of the 3D Human Eye and Its Optical Simulation

2012 ◽  
pp. 227-262
Keyword(s):  
Geometric Model ◽  
Optical Simulation ◽  
Human Eye

scholarly journals Constructing a Computer Model of the Human Eye Based on Tissue Slice Images

2010 ◽  
Vol 2010 ◽  
pp. 1-10 ◽  
Author(s):  
Peishan Dai ◽  
Boliang Wang ◽  
Chunbo Bao ◽  
Ying Ju
Keyword(s):  
Computer Model ◽  
Geometric Model ◽  
Three Dimensional ◽  
Tissue Slice ◽  
Central Axis ◽  
Virtual Surgery ◽  
Three Dimensional Model ◽  
Human Eye ◽  
Eye Tissues

Computer simulation of the biomechanical and biological heat transfer in ophthalmology greatly relies on having a reliable computer model of the human eye. This paper proposes a novel method on the construction of a geometric model of the human eye based on tissue slice images. Slice images were obtained from an in vitro Chinese human eye through an embryo specimen processing methods. A level set algorithm was used to extract contour points of eye tissues while a principle component analysis was used to detect the central axis of the image. The two-dimensional contour was rotated around the central axis to obtain a three-dimensional model of the human eye. Refined geometric models of the cornea, sclera, iris, lens, vitreous, and other eye tissues were then constructed with their position and ratio relationships kept intact. A preliminary study of eye tissue deformation in eye virtual surgery was simulated by a mass-spring model based on the computer models developed.

Super Wide Field of View Head Mounted Display Using Catadioptrical Optics

2006 ◽  
Vol 15 (5) ◽  
pp. 588-598 ◽  
Author(s):  
Hajime Nagahara ◽  
Yasushi Yagi ◽  
Masahiko Yachida
Keyword(s):  
Mixed Reality ◽  
Peripheral Vision ◽  
Field Of View ◽  
Optical Simulation ◽  
Wide Field ◽  
Stereoscopic Images ◽  
Human Eye ◽  
Head Mounted Display ◽  
Head Mounted Displays ◽  
Wide Fov

Many virtual reality, mixed reality, and telepresence applications use head mounted displays (HMD). HMD systems are portable and can display stereoscopic images. However, the field of view (FOV) of commercial HMD systems is too narrow for conveying the feeling of immersion. The horizontal FOV is typically around 60°, significantly narrower than that of the human eye. In this paper, we propose new display optics for a super wide FOV head mounted display. The proposed optics consists of an ellipsoidal and a hyperboloidal mirror that will display distortionless images by using the characteristics of the mirrors, even if the image has a large FOV. We constructed a prototype HMD system with a 180° horizontal × 60° vertical FOV that includes the peripheral vision of the human eye. The FOV has a 60° × 60° overlap area that can display stereoscopic images. We estimated the resolution, focus, and aberration of the prototype in an optical simulation and experimentally confirmed that the prototype displays distortionless wide FOV images.

A New System For Optomanual Semiautomatic Quantitative Image Analysis

1977 ◽  
Vol 35 ◽  
pp. 210-211
Author(s):  
H.P. Rohr
Keyword(s):  
Image Analysis ◽  
Volume Density ◽  
List Type ◽  
Distribution Analysis ◽  
Type Number ◽  
Point Counting ◽  
Human Eye ◽  
Quantitative Image ◽  
Point Density ◽  
Electronic Counting

Today, in image analysis the broadest possible rationalization and economization have become desirable. Basically, there are two approaches for image analysis: The image analysis through the so-called scanning methods which are usually performed without the human eye and the systems of optical semiautomatic analysis completely relying on the human eye.The new MOP AM 01 opto-manual system (fig.) represents one of the very promising approaches in this field. The instrument consists of an electronic counting and storing unit, which incorporates a microprocessor and a keyboard for choice of measuring parameters, well designed for easy use.Using the MOP AM 01 there are three possibilities of image analysis:the manual point counting,the opto-manual point counting andthe measurement of absolute areas and/or length (size distribution analysis included).To determine a point density for the calculation of the corresponding volume density the intercepts lying within the structure are scanned with the light pen.

The Human Eye and the Photographic Camera

1913 ◽  
Vol 76 (1960supp) ◽  
pp. 51-51
Author(s):  
A. Gleichen
Keyword(s):  
Human Eye ◽  
Photographic Camera

ALGEBRA OF PREDICATES AND RELATED GEOMETRIC MODELS CREATION IN REGARDS OF UNIFIED STATE EXAM IN INFORMATICS (RUSSIAN EGE)

2019 ◽  
pp. 40-47
Author(s):  
E. A. Mironchik
Keyword(s):  
Geometric Model ◽  
Main Idea ◽  
Formal Logic ◽  
High Complexity ◽  
Geometric Models ◽  
Complexity Problem ◽  
Logical Expression ◽  
State Examination

The article discusses the method of solving the task 18 on the Unified State Examination in Informatics (Russian EGE). The main idea of the method is to write the conditions of the problem utilizing the language of formal logic, using elementary predicates. According to the laws of logic the resulting complex logical expression would be transformed into an expression, according to which a geometric model is supposed to be constructed which allows to obtain an answer. The described algorithm does allow high complexity problem to be converted into a simple one.

Reabilitação estética de incisivo central superior severamente escurecido

2020 ◽  
Vol 12 (45) ◽  
pp. 91-96
Author(s):  
Washington José Batista das Neves ◽  
João Paulo Alves da Silva Aguiar ◽  
Jamile Menezes de Souza ◽  
Evandro Augusto Feitosa de Lima Amorim ◽  
Marlus da Silva Pedrosa ◽  
...  
Keyword(s):  
Clinical Case ◽  
Tooth Whitening ◽  
Human Eye ◽  
Self Confidence ◽  
The Face ◽  
Natural Dentition ◽  
Dental Whitening

Dental unit darkening is the cause of aesthetic complaint by the patient, mainly because it is easily noticed by the human eye. Tooth whitening and ceramic veneers allow aesthetic rehabilitation in a pattern of visual equality to the natural dentition, by restoring teeth color and shape symmetry, bringing to the face a harmonious impact that is reflected in the entire set that composes it. By recovering teeth healthy appearance, this association of procedures restores people’s self-confidence. This study reports a clinical case of an esthetic management for darkened tooth 21, describing the sequence of techniques association of dental whitening and ceramic veneer to achieve aesthetics balance, showing the advantages and limitations of these procedures.

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