3: The Photoreceptor Mosaic

Slides:

Advertisements

Similar presentations

VISION IN CICHLIDS Optical quality and visual perception in Cichlidae (Pisces)

Advertisements

Fourier Theory in Seismic Processing

LIGHT AND THE RETINAL IMAGE: KEY POINTS Light travels in (more or less) straight lines: the pinhole camera’s inverted image Enlarging the pinhole leads.

What is vision Aristotle - vision is knowing what is where by looking.

Perceptual Systems. Readings, Class 1: Wolfe Ch 1,2 Kandell et al Chapters 26 Sources: Wolfe, J, Kluender, K, Levi, D. et al Sensation & Perception 2012.

Visual Acuity Adler’s Physiology of the Eye 11th Ed.

Color Perception Combined rod + cone response yields both color and brightness perception Cell responses vary with illumination conditions: –low light.

Sensation and Perception Prof David Irwin Lecture for Psych 103.

Midterm 1 was returned in this class -mean was “a little to low” - for future, Moodle will have an Open Discussion Forum for this class to catalyze engagement.

Sep 16, 2005CS477: Analog and Digital Communications1 LTI Systems, Probability Analog and Digital Communications Autumn

Multiple Choice Yes/No and True/False and Matching Study the lecture notes, textbook My office hours are after class (NOTE: I won’t talk about the test.

Sep 15, 2005CS477: Analog and Digital Communications1 Modulation and Sampling Analog and Digital Communications Autumn

Unrelated vs. Related Color Unrelated color: color perceived to belong to an area in isolation (CIE 17.4) Related color: color perceived to belong to.

The Human Eye and Vision 2 (Processing The Image)

1 Digitisation Conversion of a continuous electrical signal to a digitally sampled signal Analog-to-Digital Converter (ADC) Sampling rate/frequency, e.g.

Ch 31 Sensation & Perception Ch. 3: Vision © Takashi Yamauchi (Dept. of Psychology, Texas A&M University) Main topics –convergence –Inhibition, lateral.

The visual system Lecture 1: Structure of the eye

RGB Models human visual system? Gives an absolute color description? Models color similarity? Linear model? Convenient for color displays?

Major transformations of the light signal in the retina: 1.Temporal filtering – visual response slower than input signal. 2. Spatial filtering – local.

Optics and the Eye. The Visible Spectrum Some similarities between the eye and a camera.

Fourier Theory in Seismic Processing (From Liner and Ikelle and Amundsen) Temporal aliasing Spatial aliasing.

Chapter 2: Introduction to the Physiology of Perception.

ECE 472/572 – Digital Image Processing Lecture 2 – Elements of Visual Perception and Image Formation 08/25/11.

Foveal cones are about 2.4 μm in diameter (0.7 min of arc) Peripheral cones are about 5.8 μm in diameter (1.7 min of arc)

© 2011 The McGraw-Hill Companies, Inc. Instructor name Class Title, Term/Semester, Year Institution Introductory Psychology Concepts Vision.

Visual structure & Blind spot. Question 1 What do these devices have in common?

A Photon Accurate Model Of The Human Eye Michael F. Deering.

© by Yu Hen Hu 1 Human Visual System. © by Yu Hen Hu 2 Understanding HVS, Why? l Image is to be SEEN! l Perceptual Based Image Processing.

Austin Roorda, Ph.D. University of Houston College of Optometry

Updating the Standard Spatial Observer for contrast detection Summary Watson and Ahumada (2005) constructed a Standard Spatial Observer (SSO) model for.

산업경영공학과 IMEN 315 인간공학 4. Visual Sensory Systems THE STIMULUS: LIGHT  the visual stimuli as a wave of electromagnetic energy (fig 4.1a)fig 4.1a  visible.

Ch 31 Sensation & Perception Ch. 3: Vision © Takashi Yamauchi (Dept. of Psychology, Texas A&M University) Main topics –convergence –Inhibition, lateral.

1. What is Vision ? VISION “A process that produces form images of the external world, a description which is useful to the viewer and not cluttered.

ICS 61 – Light, Color, and the Mind. Light Thank you, Mr. Newton.

The primate visual systemHelmuth Radrich, The primate visual system 1.Structure of the eye 2.Neural responses to light 3.Brightness perception.

Sensation vs. Perception Sensation: a process by which our sensory receptors and nervous system receive and represent stimulus energy Sensation: a process.

RECEPTORS IN ANIMALS RICHARD LLOPIS GARCIA Adapted by MH A2 BIOLOGY.

Visual Acuity Adler’s Physiology of the Eye 11th Ed. Chapter 33 - by Dennis Levi

Neuroscience Cellular and molecular neuroscience Neuroanatomy Systems neuroscience.

Psychology 210 Lecture 4 Kevin R Smith. Vision Sensory System –The eye –Exactly what we sense from our environment Perceptual System –The brain –How we.

1 Human information processing: Chapters 4-9 n Computer as a metaphor for human performance n Misses role of emotion and distributed cognition ReceptorsPerception.

Visual System II: Retinal Processing. Adequate Stimulus: A stimulus of a quality and of sufficient intensity to excite a sensory receptor. Adequate Stimulus.

Sensory Processes First Hour - How does perception depend on

Structure of the lens The fibrous nature of the lens is evident in low- magnification scanning Lens fibers (micrograph 2) are mature cells that have lost.

Vision Review: Miscellaneous Course web page: October 8, 2002.

Why isn’t vision perfect? An exercise in psychoanatomy.

Electromagnetic Waves

Psychology 100:12 Chapter 5 Sensation & Perception Part III.

Neural locus of color afterimages Qasim Zaidi, Robert Ennis, Ding Cao, Barry Lee.

1B50 – Visual System Daniel J Hulme. Errata Phylogenetic – genetic history of the species Ontogenetic – experience of the individual It was Kepler who.

How the eye sees 1.Properties of light 2.The anatomy of the eye 3.The cells that transmit light information from the retina to the brain 4.Visual pigments.

Seeing READING ASSIGNMENT Discussion of Gregory’s Article on Visual Illusions – Tues Feb 17 Available in your course pack.

Understanding Psychophysics: Spatial Frequency & Contrast

DO NOW. VisionVision Our most dominating sense. Visual Capture.

E.2.1. Outline the diversity of stimuli that can be detected by human sensory receptors. Receptors detected the changes in both internal and external.

Convert Angles in Degrees to Degree and Minutes and vice versa.

Human Visual System.

Journal of Vision. 2011;11(13):27. doi: / Figure Legend:

Data Processing As a science major, you will all eventually have to deal with data. All data has noise Devices do not give useful measurements; must convert.

Vision Seeing is Believing.

Wednesday, 19 September Organisms respond to changes in their internal and external environments Eye Receptors • identify the pigments.

The Eye as a Camera Michael A. Sandberg, Ph.D.

E2 Perception of Stimuli

Human Perception 7: Pattern Sensitivity.

Human Perception 4: Wavelenght Encoding.

Light and the Electromagnetic Spectrum

David J Calkins, Peter Sterling Neuron

Data Processing Chapter 3

Quadratic model fitting to foveal measurements.

Presentation transcript:

3: The Photoreceptor Mosaic Human Perception 3: The Photoreceptor Mosaic

The Photoreceptor Types Spatial Distribution of Receptors 3.2

The Photoreceptor Types Spatial Distribution of Receptors 3.3

The Photoreceptor Types Schematics 3.4

The Photoreceptor Types Receptor drawings 3.5

The Photoreceptor Types Cone wavelength absorptions 3.6

The Photoreceptor Types Curcio et al, 1990 3.7

The S-cone Mosaic Psychophysical estimation of S-cone mosaic: Williams, Macleod and Hayhoe experiments, 1981 3.8

The S-cone Mosaic A biological estimate of the S-code spatial mosaic, DeMonasterio et al, 1985, just outside the fovea 3.9

The S-cone Mosaic: Near Periphery A biological estimate of the S-code spatial mosaic, near periphery 3.10

Calculating the Viewing Angle tan(φ)=0.0025mm/17mm=0.000147 i.e. 0.0084 degrees or 0.5 minutes or 30 seconds 3.11

Sampling and Aliasing Aliasing of signals results when sampled values are the same but in-between values are not 3.12

Sampling and Aliasing Harmonic undersampled all = 1:16; n = all/16; freq = 15; f = cos(2*pi*freq*n); plot(n,f,'b-o’);hold on all = 1:256; n = all/256; plot(n,f,'r-') 3.13

Sampling and Aliasing Harmonic oddly sampled clf all = 1:16; n = all/16; freq = 11.2; f = cos(2*pi*freq*n); plot(n,f,'b-o') hold on all = 1:256; n = all/256; freq = 15; plot(n,f,'r-') 3.14

Sampling and Aliasing F = N/2 cos(2π(N/2+f) i/N)= cos(2π(N/2-f)i/N ) Square-wave (two dimensional) aliasing Nyquist frequency F = N/2 cos(2π(N/2+f) i/N)= cos(2π(N/2-f)i/N ) 3.15

The L- and M-Cone Mosaic Perceived aliasing patterns Consistent with Nyquist frequency of 60cpd 3.16

The L- and M-Cone Mosaic Foveal mosaic no S-cones nor rods 3.17

The L- and M-Cone Mosaic Cone receptor mosaic, Roorda and Williams, 1999 all three type of cones visible, L(red), M(green), S(blue) 3.18