Transcript presentation_5mins

Interactive Display for Estimating
Eye Refractive Errors and
Accommodation Range
Vitor Pamplona, Manuel Oliveira, Ankit Mohan, Ramesh Raskar
{pamplona,manuelmo}@mit.edu, {ankit,raskar}@media.mit.edu
Eye Refractive Errors in Countries
800 million to 2.3 billion
individuals worldwide present
some kind of refractive problems
(myopia, hyperopia, astigmatism, presbyopia)
World Health Organization Reports
Access to Medical Eye Care
in the 3rd World
World Health Organization Reports
Complex and expensive devices
Light wave
Simplest Solution
Corneal Topographer
Optical Refractor
Wavefront Aberrometer
Results: Wavefront
Aberrations
Snellen Chart
Standard Prescription
Spherical: 0.5 diopters
Cylindrical: -1.0 diopters
Astigmatism Axis: 10°
Extra Info.
Estimated Prescription
Accommodation Range: -5.07 diopters
Sharp Focus Range: from 18cm to 2m
-0.5
-1.0
10°
Test Setup
Microlens
Array
LCD Display
Overall
Precision: 0.16D
Minification
Relay Optics
3600 DPI
Head Mounted Display Setup
Overall
Precision: 0.28D
Vuzix VR 920
1800 DPI
Microlens Array
Cellphone Setup
Overall
Precision: 0.71D
Controls
Pinhole Array
Viewmaster Setup
Overall
Precision: 0.5D
Sliding Masks
Pinhole Array
Health Screening Tools
Blood Oxygenation
Blood Pressure
Visual Accommodation
Body Temperature
Blood Glucose
Spherocylindrical Lens Measurement
User Study
Interactive Display for Estimating
Eye Refractive Errors and
Accommodation Range
Vitor Pamplona, Manuel Oliveira, Ankit Mohan, Ramesh Raskar
{pamplona,manuelmo}@mit.edu, {ankit,raskar}@media.mit.edu
Absolute Error
Interactive Method
Accommodation Range
Farthest Focal Point
Nearest Focal Point
(myopia, hyperopia, astigmatism)
(presbyopia)
Refractive Errors
AND Accommodation Range
Accommodation Range
Normal Vision
Wavefront aberrometers,
Auto refractometers,
Snellen-like Eye charts
Require inducing
accommodation
Myopia
Hyperopia
Presbyopia
Infinity
30cm
Close-range eye charts,
Mechanical motion
devices
Our Method
Objective
Induced Focal
Range Capability
From Near to
Infinity
Subjective
Our Device
and Interactive Method
Eye Chart
Tests
Auto
Refractometer
Spatially Resolved
Refractometer
Lens/Corneal
Topography
At Infinity Only
Spherical
Task-based
Astigmatism
Wavefront
Aberrometer
High Order
Aberrations
Surgery-based
Interactive Method
Display
As view from a normal person
Spherical: 0 diopters
Vuzix’s Head
Mounted
Display
9mm by 6.5mm
640x480 px
1800 DPI
Background
Human Eye
Cornea
~40 diopters
Crystallin Lens:
~10-20 diopters
(Accomodation)
Human Eye
Normal Vision
Infinity
Subject
can focus
at infinity
Human Eye
Accommodation Range
Normal Vision
Infinity
30cm
Normal Vision
30cm
Accomodation:
Increase optical power
Subject
can focus
close
Human Eye
Accommodation Range
Normal Vision
Infinity
30cm
Myopia
High-curvature cornea
Increased refractive power
Relaxed crystallin
Infinity
Subject
cannot
focus
at far
distances
Human Eye
Accommodation Range
Normal Vision
Myopia
Infinity
30cm
Myopia
High-curvature cornea
Increased refractive power
Little or no
accomodation
Subject
can focus
close
Human Eye
Accommodation Range
Normal Vision
Myopia
Infinity
30cm
Myopia Correction
Relaxed Crystallin
Infinity
Subject
can focus
at infinity
Divergent Lens
Human Eye
Accommodation Range
Normal Vision
Corrected Myopia
Myopia
Infinity
30cm
Hyperopia
Planar cornea
Decreased refractive power
Subject accommodates to
compensate for flat cornea
Infinity
Subject
can focus
at infinity
Human Eye
Accommodation Range
Normal Vision
Myopia
Hyperopia
Infinity
30cm
Hyperopia
Planar cornea
Decreased refractive power
Insuficient accommodation
for near vision
Subject
cannot focus
close
Human Eye
Accommodation Range
Normal Vision
Myopia
Hyperopia
Infinity
30cm
Hyperopia Correction
Infinity
Convergent Lens
Accommodation Range
Normal Vision
Myopia
Corrected
Hyperopia
Hyperopia
Infinity
30cm
Now, subject
can focus
at infinity
without
accommodation
Human Eye
Presbyopia
Loss of accommodation
power over years
Insufficient
accommodation
Subject
cannot
focus
close
Human Eye
Accommodation Range
Normal Vision
Myopia
Hyperopia
Presbyopia
Infinity
30cm
Presbyopia Correction
Even with reduced
accommodation, subject
can focus close
Human Eye
Accommodation Range
Glass
Normal Vision
(no optical power)
Myopia
Near
Correction
Hyperopia
Corrected
Presbyopia
Presbyopia
Infinity
30cm
Astigmatism
Different eye meridians
focus at different depths
Point
Blurred
vision
Human Eye
Astigmatism Correction
Lens with 2 main refractive power axes
Oriented 90 degrees from each other
Spherical Refractive Power Axis
Spherical Axis
(Counter-clockwise,
from horizontal line)
Cylindrical Refractive Power Axis
Presbyopia
Loss of Accomodation
power over years
Infinity
Subject can
focus
at infinity
Human Eye
Accomodation Range
Normal Vision
Myopia
Hyperopia
Infinity
30cm
Corneal Deformations
Corneal Deformated
Infinity
Subject can
focus at
Infinity but
with artifacts
Human Eye
30cm
Subject can
focus close
but with
artifacts
Human Eye
Normal Vision
Microlens Array
Focal Length
Cellphone
Subject’s View
Bad Farsightedness
Microlens Array
Focal Length
Cellphone
Subject’s View
Correcting Bad Farsightedness
Microlens Array
Focal Length
Cellphone
Subject’s View
Correcting Bad Farsightedness
Microlens Array
D
C = f(D)
D
Focal Length
Cellphone
Subject’s View