Embed Size (px)
DESCRIPTION
Perceptual versus Cultural. Architecture for visual thinking. Intro to Human Visual System and Displays. Fundamental Optics Fovea The ultimate Display. Human Visual Field. Visual Angle. 1 diopter: a lens that focuses at 1 meter. 45d. ~15d. Acuities. Vernier super acuity (10 sec). - PowerPoint PPT Presentation
Citation preview
Perceptual versus Cultural
a
AB
C
D
Architecture for visual thinking
a
AB
C
D
Intro to Human Visual System and Displays
Fundamental Optics Fovea The ultimate Display
Human Visual Field
aa
100
80
60
LEFT RIGHT
40
20
Visual Angle
dr
h
1 diopter: a lens that focuses at 1 meter.
45d
~15d
Acuities
Vernier super acuity (10 sec)
Grating acuityTwo Point acuity (0.5 min)
Human Spatial Acuity
Cutoff at 50 cycles/deg.
Receptors: 20 sec of arc Pooled over larger and larger areas 100 million receptors 1 million fibers to brain A screen may have 30 pixels/cm – need
about 4 times as much. VR displays have 5 pixels/cm
Anti aliasing
Input pattern
Output pattern
Pixel matrix
Temporal Aliasing
Human Flicker fusion 50 Hz Temporal aliasing occurs with moving
targets Must compute motion blur to fix the
problem
Acuity Distribution
aaa
10 30 50103050
Distance from Fovea (deg.)
100
80
60
40
20
Brain Pixels
Brain pixels=retinal ganglion cell receptive fields
Tartufieri
Field size = 0.006(e+1.0) - AndersonCharacters = 0.046e - Anstis
Ganglion cells
Brain pixel distribution
Ideally get information into every brain pixel
aaa
10 30 50103050
Distance from Fovea (deg.)
100
80
60
40
20
Pixels and Brain Pixels
aaa
10 30 50103050
Distance from Fovea (deg.)
100
80
60
40
20
0.2 BP
1 bp
Small Screen
0.8 BP
Big Screen
1280x1024 simulated
Monitor
0
100
200
300
400
500
600
700
0 50 100 150 200
Display Width (cm)
Bra
in P
ixel
s
Total BP
BP Stimulated
CAVE
A conventional monitor covers <45% of our brain pixels
Percent of Brain Pixels Uniquely Stimulated in region covered by the display
0
10
20
30
40
50
60
70
80
90
100
0 50 100 150 200
Display Width (cm)
Per
cen
t st
imu
late
d
Display
Parafovea
Monitor Cave
How efficiently can we use each display?
It will take approximately 2.5x as long to fixate targets at the edge of the big screen
Head movements accompany eye movements > 25 deg.
Scale matters
Parafovea
Ultimate Display
a
High resolutionbinocular insert (25x19)
Left eyebackground(82.5x66.7)
Right eyebackground(82.5x66.7)
Binocular overlap
University of Illinois
100mpixel display
Data walls (near immersion) Stereo, no head tracking, wide screen
CAVE Head tracking – stereo-one user Light scattering problems Interaction problems
Depth of Field
1/3 diopter detectable focus: standard pupil
50 cm 43cm 60cm 1 m 75cm 1.5m 2m 1.2m 6.0m 3m 1.5m infinity
1 1 1 = +
f1 f2 f3
Ultimate Display
Use an eye tracker tomeasure direction of gaze
Ascertain distance toobject
Change focal length oflens so that fixated virtualobject is at correct focal distance
Screen
Compute graphics imagery so thatobjects at different focal distancesappear out of focusAttempt to determine
fixated object
Ultimate Display
Augmented Reality
Virtual imagery
Real-world imagery
Computer Display
Issues
Depth of focus Occlusion Registration
Augmented reality (Feiner)
Add text+images to real world See through glasses Very sensitive to head tracking
Augmented Reality Binoculars
Uses a video camera
Or Beam splitter.
Why don’t we use HUDs more?
Text Television
Why don’t we use HUDs more?
Text Television
Monocular binocular Screen width Blocking the real world Eyeglasses
Immersadesk Stereo, Head tracking*
Ultra Hi-Resolution Wheatstone Stereoscope
