the glenn a. fry lecture treating with spectacle lenses: a novel idea!? "what has been is what...
TRANSCRIPT
The Glenn A. Fry Lecture
Treating with Spectacle Lenses:A Novel Idea!?
"What has been is what will be, and what has been done is what will be done;there is nothing new under the sun.”
Ecclesiastes 1:9
Eli Peli, MSc, OD, FAAO
The Schepens Eye Research Institute Harvard Medical School
My First Refraction
• At the Haifa Zoo (1975)
– Helping Jake Sivak
• The Mongoose refused to be fitted with any type of spectaclesfor day or night use
My Second Refraction Customer
• Helping Mogi Gur and Jake Sivak
• Determine refraction by listening to sounds of neural activity in the cortex, monitored with intracellular electrodes, while changing lenses 13
lever and eye occluder signal
neuronal discharge
Eye
pos
ition
spike timing, AP waveforms, eye position
Cur
sor
mov
ing
with
eye
spik
e tim
ing,
eye
pos
ition
Water pump control
Stimuli generation
Wat
er p
ipe
and
spoo
n
12
5
9
14
15
6
3
7
10
16
17
8
4
12
11
There must be easier ways to refract!
Are there more ways to use thespectacle lenses?
Yes. With Multiplexing!
Multiplexing for Low Vision• Providing peripheral (wide field-of-view)
together with central (high resolution) vision
in ways that make them
perceptually separable and useful
– Many different forms of multiplexing -
• Spatial (superposition), Temporal (alternating),
Biocular, or Spectral (colors)
– Maintaining free head & eye movements
Peripheral Prisms for Hemianopia
• Expands upper and lowerfields by about 20 degHigh power prisms (40)
• All positions of gaze affected
• Biocular multiplexing
• Prismatic color fringes mark eye of origin
• Spectral Multiplexing
Left Hemianopia
Instantaneous View with Left Hemianopia
Field expansion for homonymous hemianopia by optically induced peripheral exotropia. Opt. & Vis.Sci 77;453-464
View withthe Peripheral Prisms
Effect Demonstrated with Perimetry
B
WithoutPrisms
Perimetrywith Peripheral Prisms
B
WithoutPrisms
WithPrisms
Cosmetically Acceptable Dangerous?
MultiOptical, Sweden
Peripheral Prisms Spectacles
Peripheral Prisms SpectaclesNew more attractive, safer designs
Chadwick Optical
Solar Glare• Need to block peripheral
field
• Sunglasses and tinted visors-not dark enough
• Opaque visor-fixed
• Hand position is adjustable
Headlight Glare at Night
Coming from a limited section of peripheral field
Multiplexing Glare Control Lenses
• Block peripheral view
• Top strip for solar glare• Left strip for headlight glare
• Fine adjustments with head position are simple, accurate, and intuitive
Lens Tint
Clip-On
Patent Search
US 5,428,409
US 4,338,003
US 5,252,997
US 4,828,380
US 3,199,296
All for Night Glare All static - no movement
Traffic Lights at Night
Difficult for drivers with color deficiencywith low visionor both
Unilight® LED traffic lights
As seen in Fort Hood, TX & Cheyenne, WY
As seen in Scottsdale AZ
No position clue
No shape clue
Multiplexing Spectaclesfor Red-Green Color Deficiency
• When traffic-light is noted,slight head tilt brings itinto the red-tined zone
• Red light shines through
• Green light is blocked
Successful application of Temporal Multiplexing Bioptic Telescope
• Wide field through the carrier lens
• Occasional head tilt togain high resolution
• Limitations– Ring scotoma, Cosmesis, Social eye contact
45 degree field
In-the-Lens Telescope
View from above
t
Lens thickness, t, limits width of field
Galilean Telescope
Completely embedded in the lens
t
Mirrors Only Design
Looking Through the Carrier
Looking Through the Telescope
Wider Field-of-View
In-the Lens Keplerian Telescope
t
t
Front View Side View
Lens thickness, t, limits height of field
SimulVision-Spatial Multiplexing
Conclusion• Multiplexing offers a new way of thinking
about low vision devices – Electronics or optics
• Multiplexing is useful in other applications
• Cosmetic considerations are critical to the success of any spectacle born device – We are all vain
“…vanity of vanities; all is vanity”Ecclesiastes 1:2
Thank You!
Supported generously by NIH grants
Solar Glare
Adaptation withPeripheral Prisms
After few weeks of adaptationPresumed
QuickTime™ and aPhoto - JPEG decompressor
are needed to see this picture.
In-the-Lens Galilean Telescope
Multiplexing Glare Control Lenses
• Block peripheral view
• Top stripe for solar glare• Left stripe for headlight glare
• Fine adjustments with head position are simple, intuitive, and accurate
Disclosure
• I have financial interest in a number of the devices I’ll be talking about.
• I am a consultant to some of the companies
• I have patent applications pending regarding some of the others