Seeing a Three- Dimensional World

Jie Ju Lin

Outline

• Introduction• Major sources of depth

information• Binocular and Monocular• Static cues • Sensation and perception

Introduction

Major sources of depth information

Depth information

Oculamotor Visual

Accommodation( 水晶體 )

Convergence( 聚集角度 )

monocularBinocular( 視網膜 )

Static Motion parallex

(Adapt from Randolph al., 2006)

Binocular and Monocular

• Binocular

Seeing with two eyes.

The retinal disparity between these imagines provides a depth cue.

(Stereoscopic display)

• Monocular

Seeing with one eyes

static cues

• Interposition:

(partial occlusion)

Refers to the appearance of one object is partially covered by another.

If one object practically covered by other,

the fully exposed one is perceived as nearer

• The circle appears to line behind the rectangle ,which appears to lie behind the triangle.

static cues

• Shading and Light

When objects are lighted from one direction, they normally have shadow that offer some cure about the objects’ orientation relative to us.

The surface of an object nearest the light source is generally the brightest.

static cues

• Liner Perspective

Liner perceptive involve systematically decreasing the size of more distant elements and the space separating them.

when we see two converging line, we

assume that they are two parallel lines receding in depth .

static cues

• Relative size:

(familiar size)

If objects are known to be the same true size, those subtending a smaller visual image on the retina (the retina imagine) are assumed to be farther away.

static cues

• Textural gradients

Most surfaces textured, and when the plane of a texture is oriented toward the line if sight, the grain will grow finer at greater distance.

static cues

• Aerial perspective:

(clearness)

Is due to the effect of very small particles in atmosphere on light.

more distant objects often tend to be hazier and less clearly defined.

Sensation and perception

Distal Stimulus

3D

Proximal

Stimulus

2D

Perception3D

Sensation and perception

Interposition

Aerial perspective

Textural gradients

Relative size

Shading and Light

Liner Perspective

Sensation and perception

Sensation Perception

Noun Meaningless mental qualities

Meaningful understanding of world/self

verb Physical process

Logical process

(Adapt from Goldstein, 2007)

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