Note: Descriptions are shown in the official language in which they were submitted.
84-FP-8403
LO~ VISION EYE GLASSES
FIELD OF THE INVENTION
This invention relates to improved eye glasses
for use by people with macular (retinal) degeneration,
optic nerve damage or similar low vision problems, to
5 - the lens assemblies, per se, used in such eye glasses;
and to the method of improving the vi~ion oE a user of
such eye glasses and lenses.
DESCRIPTION OF THE PRIOR ART
Various types of apparatus have been devised for
people with vision problems. The most common of such
apparatus are eye glas~es for focusing light rays of
an object being viewed onto the macular retinal
membrane on the rear of the eyeball. Inadequate
ocusing is not uncommon and in general is caused by
the improper ocusing by the cornea and lens of the
eyeball. When the cornea and lens do not function to
properly bend or refract the incoming, image-bearing
light rays, such light rays are not properly focused
upon the macular retinal membrane and, as a result~
the optic nerves cannot convey the proper information
to the brain to effect proper vision. Many such
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problems are cau~ed by non spherical eyeballs
Mechanical lenses can normally correct this type of
vision problem. Such mechan:ical lenses may take the
form of contact lenses, eye gla.sses or the like and
have been in common usage for many years.
When, however, faul~y vision is caused either by
the degeneration of the whole or part of the macular
retinal membrane on the back or interior face of the
eyeball, or by the deterioration of the optic nerve
which would normally carry the images from the macular
retinal membrane to the hrain, standard lenses are
generally insufficient to restore proper vision to the
patient so afflicted.
Various commercial devices for overcoming low
vision problems have received limited commercial
acceptance. One of these devices is the Finebloom
System. The Finebloom System is constructed of tube-
type devices consisting of mirrors that attach to a
conventional pair of eye glasses. This apparatus
allowY a patient using such system to focus on objects
at one particular distance. The mirrors of the tubes
intensify the focused light to allow the degenerated
macular retinal membrane, or degenerated part thereof,
or the deteriorated optic nerve to function again to
thereby restore some vision. Different tubes must be
utilized for focusing at different distances.
Additionally, such a system restricts the user to
properly pinpoint or tunnel vision.
Another low vision aid is the Opticon System.
This system consists of diverging contact lenses of a
negative power used in optical cooperation with
additional conventional converging lenses of positive
power. The positive lenses must ~e moved toward or
84-FP-8403
3 --
away from the contact lenRes and eyes of the user to
focus in a manner ~imllar to a telescope. Patients
utilizing ~uch a system have ~ w~aer field of vision
than they would experi~nce with the Finebloom System,
but ~agnification become~ a problem vertex distance,
or di~tance from the contact lens of negative power to
the front of the forward lens of positive power,
creates a telescopic image much larger than normal
size. This results in a depth perception problem for
the user. Objects being viewed thus appear much
closer than they really are. Further, as a practical
matter, a great percentage of users of systems of this
type are older and encounter problems applying and
removing their contact lenses.
Various prior art disclosures describe lens
arrangements in combinations which have limited
structural similarities to the lens arrangement of the
present invention. The original telescope by Galileo,
for example, utilized negative power lens close to the
eye of the user in optical combination with a positive
power lens supported by a tube at fi~ed distance from
the negative lens. Most telescopes now provide for
relative displacement between lenses to enable
focusing at different distances. Furthermore,
telescopes are designed for magnifying rather than for
achieving the effective one-to-one focusing which is
the objective for normal eye glass use.
Other lens arrangements which utilize combined
lenses of positive and/or negative characteristics are
found in U.S. Patent Numbers 2,474,837 to Glancy and
3,511,558 to Uberhagen. These disclosures are
directed to apparatus for use as magnifiers as in
telescopes or cameras, a totally different function
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84-FP-8403
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than the present inven~ion which seek~ to retain a
one~to-one imaging with increased illumination over a
range of distances for correcting low vision problems.
Even though structural similarities may exist between
the present inVention and these prior art devices,
their structural dissimilarities preclude their use
for the purposes of the present invention.
Additionally, other prior art disclosures which
describe lens arrangements for eye glasses can be
found in U.S. Patent Numbers 968,69~ to Rohr,
2,092,789 to Tillyer ~,702,218 to Manhire: and
3,877~978 to Tolar. In all of these prior art
di~closures, the len~ assemblies are directed to
combinations of lense~ of varying shapes and powers to
correct the problems a patient may have in focusing
light rays onto the macular retinal membrane as caused
by an improperly functioning cornea and ]ens rather
than focusing at a particular selected area of the
retina. None of the prior art arrangements of lenses
provides for light intensifying capability to help
patients who have low vision problems as caused by
macular degeneration, optic nerve damage or the like.
In most cases, these prior art patents describe lens
arrangements which combine their positive and/or
negative lenses together into a single lens. They
therefore function as a single lens solely for the
purpose of improving the focusing capabilities of the
patient. Further, as discussed above, even though
structural similarities may exist between the presen~
invention and these prior art devices, their
structural dissimilarities preclude their use for the
purposes of the present invention.
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Although many lense~3 and o~her optical devices in
various combinatiorl~ h~ve ~een propo~ed in t~he past
for overcoming a wide range of opti.cal problems, none
teaches the pre~ent inventive use of eye glasqes
having lenses of po~itive and negatlve powers,
separated by a fixed air space and incorporating a
prism for their purposes, objective~ and advantages of
overcoming macular degeneration, optic nerve damage
and similar low vision problems. The present
invention overcomes the problems of the prior art ana
achieves its objectives and advantage~ with a minimum
number of functioning part~ and at a minimum cost.
The pre~ent invention also eliminates both the need
for a patient to endure tunnel or pinpoint vision and
eliminate~ the need for a patient to wear a bulky
apparatus or one which would require constant
readjustment for focu~ing. These objectives and
advantages should be construed to be merely
illustrative of some of the more prominent features
and applications of the present invention. Many other
beneficial results can be attained by applying the
disclosed invention in a different manner or modifying
the invention within the scope of the disclosure.
Accordingly, other objects and advantages, as well as
a fuller understanding of the invention, may be had by
referring to summary of the invention and the detailed
description describing the preferred embodiments of
the invention in addition to the ~cope of the
invention as defined by the claims taken in
conjunction with the accompanying drawingsO
4 ~ ~
84-FP-8403
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SUMMARY OF THE INVENTION
The present invention is defined by the appended
claims with specific embodiments Rhown in the attached
drawings. For the purposes of summarizing the
invention, the invention may be incorporated into eye
glasses for projecting light rays at essentially one-
to-one magnification~ comp~ising a fir~t lens of
positive optical characteristics, a second lens of
negative optical characteristics incorporating a prism
and means to secure the first lens and second lens
with respect to each other. A ~pace is formed between
the lenses at lea~t in their central regions. The
first lens has at least one convex surface and,
preferably, two concave surfaces. The space between
the lenses is between about 1.2 millimeters and about
1.5 millimeters. The first lens has an edge thickness
of between about 0.5 millimeters and about 1.5
millimeters, The side o the first lens which is
closer to the second lens has a convex surface with a
curvature of between about 2.13 diopter and about 4~76
diopter. The second lens has a center thickness of
between about 1~2 millimeters and about 1.6
millimeters. The side of the second lens which is
closer to the first lens has a concave surface with a
curvature of between about 4.29 diopter and about 6.72
diopter. In an alternate embodiment of the invention,
a bifocal lens is formed as part of ~he first lens.
The present invention also includes improved
glasse~ for use by people with low vision problems
such as macular degeneration, optic nerve damage or
the like. The lmproved glasses comprise a lens
assembly having a magnifying lens for converging
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84-FP-84V3
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received llght and a reducing lenq for diverging
received light and a frame for supporting the lens
assembly at a predetermined ai~tance from an eye of a
user and for ~upporting the lenses in a predetermined
orientation with re~pect to each other with the lenses
defining a space therebetween along the optical axes
of the lenses. The space between the lenses is
between about 1.2 millimeter~ and about 5.0
millimeter~. The edge of the magnifying len~ hac a
thicknes~ of between about 0.5 millimeters and about
1.5 millimeters. The size of the magnifying lens
which iB adjacent to the space has a convex surface
with a curvature of between about 2.13 diopter and
about 4.76 diopter. The reducing len~ has a central
thickness of between about 1.2 millimeters and about
1.6 millimeters. The side of the reducing lens
adjacent to the space has a concave surface with a
curvature of between about 4.29 diopter and about 6.72
diopter. In an alternate form of the invention, the
glasse~ may further include a bifocal lens formed as
part of the magnifying len~.
The present invention may also be considered as
comprising eye glasses for improving the vision of
people with macular degeneration, optic nerve damage
or similar low ~ision problems. Such eye glasses
include two lens assemblies. Each assembly has a
magnifying lens with two convex surfaces and an edge
thickness of between about 0.5 millimeters and about
1.5 millimeters. Each assembly also has a reducing
lens with two concave surface and a central thickness
of between about 1.2 millimeters and about 1.6
millimeters. The lenses of each assembly are aligned
along their optical axes. Such eye glasses also
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84-FP-8403
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include a frame for supporting each lens of each
assembly at a predetermined distance from an eye of a
user and for ~upporting the lenses of an a~embly in a
predetermined orienta~ion with respect to each other~
5 The lense~ of each as~embly define an air 5pace of at
least between about 1.2 mil:Limeters and about 5.0
millimeters therebetween along their optical axes.
For each assembly, the side of the magnifying len~
which is adjacent to the space ha~ a surface with a
convex curvature of between about 2.13 diopter and
about 4.76 diopter. For each assembly, the side of
the reducing lens adjacent to the space has a surface
with a concave curvature of between 4.29 diopter and
6.7~ diopter.
The present invention also includes the method of
improving the vision of a patient suffering from a low
vision problem such as macular degeneration, optic
nerve damage or the like. The method comprises the
steps of converging, through a first lens, image
bearing light rays from an object being viewed and
projecting such converged light rays toward the eye of
such patient. The method also includes the steps of
diverging, through a second lens, the projected light
rays and projecting such diverged light rays at a
predetermined location within the eye of such patient.
The method further includes directing additional
ambient light onto the retina for improving the image
sensitivity thereof. Lastly, the method includes the
step of angularly positioning the first lens with
respect to the second lens so as to selectively focus
an image onto a person's retina, the second lens being
~aintained at a predetermined distance fro~ the eye of
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84-FP-8403
_ g _
such patient regardLe8~ of the distance to the object
being viewed.
The foregoing has outlined rather broadly the
more pertinent and important features of the present
invention in order that the detailed description of
the invention that follows may be better understood so
that the present contribution to the art can be more
fully appreciated. Additional features of the
invention will be describe~ hereinafter which form the
subject of the claim~ of the in~ention. It should be
apprec~ated by those skilled in the art that the
conception and the specific embodiments disclosed
herein may be readily utilized as a ba~is for
modifying or designing other structures for carrying
out the same purposes of the invention. It should be
realized by those skilled in the art that such
equivalent constructions do not depart from the spirit
and scope of the invention as set forth in the
appended claims.
BRIEF DESCRIPTION OF THE DRAW_NG
For a more complete understanding of the nature,
objects and advantages of the present invent;on,
reference ~hould be had to the following detailed
description taken in conjunction with the accompanying
drawings in which:
FIG. 1 i5 a top view of a lens frame assembly for
utilizing the lenses of the present invention;
FIG~ ~ is a rear view of the lens frame assembly
of FIG. l;
84-FP-8403
FIG. 3 is a bottom view of the lens frame
as~embly of FIG. 1 showing the hinging action of the
assembly;
FIG. 4 is a cro3s-sectional view of one form of
the inventive lens assembly; and
FIG. 5 is a planar view of an inventive convex
lens forming a part of the present invention.
DETAILED DESCRIPTIQN OF TE~E INVENTION
FIGS. 1, 2 and 3 illu~trate one form of eye glass
frame as3embly 10 for supporting the inventive lens
a~semblies and for improving the vision of patients
suffering from low vision problems such as macular
degeneration, optic nerve damage or the like. The
frame assembly includes a standard lens support frame
or rim 12 for rigidly holding a magnification lens in
proper orientation with respect to an eye of a user of
such eye glasses. The rim 12 is preferably plastic so
as to have low weight while providing massive support.
The interior surface of rim 12 is provided with a
groove in a manner well known in the art formed as an
inset ledge adapted to receive the edges of a lens for
maintaining it in a desired position. The frame
assembly also includes elongated side stems 14 and 16
terminating in downturned arms for positioning behind
the ears of a user ~or securing the glasses on the
head of the user so as to hold the frames and,
consequently, the lens asqemblies, in proper
orientation with respect to the eyes of a user.
Hinges 18 and 20 are preferably provided at the
forward ends of the stems adjacent the rims to permit
84-FP-8403
the folding of the parts of the eye glasses into a
compact arrangement when not in use. A bridge 22
couples two len~ openings 24 and 26 across the nose of
a user. In such manner, the optical axes of a lens
held in the frame as~embly 10 normally coincides with
the optical axes of the eyeballs of a user so that: the
objects being viewed are usually aligned in a
predetermined orientation for proper vision.
The frame assemb]y 10 al~o includes an inner
frame 28 for holding a second pair of lenses in a
predetermined position with respect to the lenses held
in frame 12. The frame 28 is also of a type well
known in the art and preferably comprise~ a wire frame
having low ma~s 80 that the combined size of frames 12
and 18 is maintained relatively small. As can be seen
in the view of FIG. 1, frame 1~ i~ hinged to frame 28
by hinge~ 30 and 32 which allows the frame 12 to pivot
as much as five millimeters with respect to frame 28.
FIG. 3 shows the pivoted frames. As will becomes
apparent from the discussion to follow, one of the
innovative features of this system is the combination
of a pri~m efEect into the inventive lenses so that
the viewed image may be focused onto a particular area
of a retina. In some patients, eng., diabetic
patients, that portion of a retina which is responsive
to light may vary from day-to-day. By providing a
slight adjustment of the relative positions of the
frame 12 and 28, the position of the focused image may
be varied. So long a~ the optical centers of the
lenses are not affected, the image will not
deteriorate. The inner frame 28 also includes nose
piece~ 34 and 36 for supporting the frame assembly 10
on the nose of a user in the well known manner.
84-FP-8403
- 12 -
One form of lens assembly is shown in the cross-
sectional view of FIG. 4. The first or outer lens 38,
that lens most distance from the eye 40 of the user,
i8 of a positive power or positive optical
characteristic~ and function~ as an enlarging lens for
the optical ~ystem~ Such a lens will function to
converge light rays received from an object 42 being
viewed. In the preferred embodiment of the invention,
this lens is formed with two convex surfaces, one at
its front or outer side 44 and one at its back or
inner side 46. Normally, for a positive lens, at
least one surface of the lens must be convex. This
lens is Of sufficient size to effect its appropriate
imaging function with its edge thickness being between
about 0.5 millimeters and about 1.5 millimeters. Its
inner side 46, that side closer to the eye of a user,
preferably has a convex surface with a curvature of
between about 2.13 diopter and about 4.76 diopter. A
diopter is a unit of measurement of the refractive
power of a lens e~ual to the reciprocal of its focal
length measured in meters.
The second lens 48 of each optical system i8 of a
ne~ative power or negative optical characteristics and
functions to reduce the image being viewed by
diverging received ligh~ rays. This lens is
preferably formed with two concave surfaces, one at
its front or outer side 52 and one at its back or
inner side 54. ThiB lens preferably is of slightly
larger diameter than len~ 38 and has a center
thickness of between about 1.2 millimeters and about
1.6 ~illimeters. The curvature of the first or outer
side 52 of the second lens 48 preferably is between
4.29 diopter and 6.72 diopter.
84-FP-8403
The various lense~ of the optical asse~blie~ are
preferably for~ed of gla~s or plastic of commercial
lens quality and performance characteri~tic~. Such
materials are well known in the art, readily available
in the market place and are fully described in the
published literature.
The space 50 between the lense~ along their
optlcal axes 62 i~ normally between about 1.2
millimeters and 1.5 millimeters. The image-bearing
light rays from an object being viewed are converged
by the first lens 38, pass through the space 50, and
are then diverged by pas~age through the second lens
48. The lens assembly, i.e., lenses 38 and 48, is
designed and configured so as to produce an
essentially one-to-one magnification which is
preferred for eye glass usage. The space between the
lenses 38 and 40 can be varied by the hinged frame
assembly. In the bifocal area, the lenses can be
moved to be as much as 7.5 millimeters apart. This
additional separation can provide additional
magnification in the bifocal area.
While the above description i8 principally
directed to the lens as~embly or system including
certain lenses and a space between them to improve the
low vision problems of a user, the invention should
also be construed as including the eye glass frames in
combination with the lens assemblies for supporting
two such assemblies with the lenses of each assembly
in proper orientation with respect to each other and
also in proper orientation with respect to the eyes of
a user.
FIG. 4 also illustrates, added to the first lens
38, preferably on its outer or front surface 58, a
9tl'~
84-FP-8403
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bifocal lens 54. The bifocal lens is d2signed ~oeffect a proper prescription and is located or
disposed at the bottom of the Eront of the irst lens
adjacent the front of the rim. It constitutes a minor
extent of the lens ~urface. This bifocal lens
functions in a normal fa~hion as a standard bifocal
lens permitting a uqer to read at close distances by
viewing through the major extent ~f the lenses.
Bifocals, as well a~ their method~ of fabrication and
use, are well known in the art. In addition to the
normal bifocal function, eye glasses with bifocal
lenses constructed in accordance with the present
invention provide the image intensification functions
for people with low vision problems as described
herein above.
Referring to FIG~ S, there is shown a front view
of the inner lens 48 of ~he present invention. The
outer line 74 represent~ the beginning edge of the
outer concave surface 52. The inner line 76
represents the beginning edge of the inner concave
surface 54. The po~itions of the lines 76 and 74 have
been exaggerated for clarity. The relative difference
in diameter of the outer and inner concave surfaces 52
and 54 defines a prism or circular refractive
interface 78 which is actually a reflection of the
surface 80 (see FIG. 4). The prism surface 78
enhances the light gathering ability of lens 48 and
brightens images directed to the eye. By shifting the
relative position of the surfaces 52 and 54 and
varying the relative size, the image can be focused on
areas of the retinal membrane 70 which are active or
undamaged, i.e., the optical center of the lens 48 can
be shifted to change to focal area on the eye.
84-FP-8403
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Preferably, the diameter of the inner concave surface54 i~ maintained constant while the diameter of the
outer concave surface 52 may be varied as required.
Typically, the surface 54 will have a aiameter of 35
millimeter~ while the diameter of ~urface 52 may vary
between 38 and 50 millimeters. va~iation of one
millimeter in the size of the defined prism ~urface
will shift the image by five degrees angularly with
respect to the optical axis of the lenses. From the
above, it will be appreclated that the len~ system
provides two ~eparate and distinct functions. The
first function is to direct an image onto an optically
respon~ive portion of a user's retina. The second
function is to act as a light gatherer to intensify
the amount of light directed toward the retina. It is
believed that the light gathering function may be of
more significance than the image directing function.
For example, in some tests for visual acuity in which
the patient i8 placed in a darkened room and directed
to observe an image on a screen, it has been found
that very little improved vision could b0 measured.
However, the same patient in a well lighted room
experienced a significant improvement in visual
acuity. This light gathering function i8 believed due
to the prism surface 78 which can be shown to be
effective in directing light toward the retina. Note
that it is not believed that the prism surface 78
redirects the viewed image but only that it increases
the amount of light entering the eye and therefore
makes the eye more sensitive to image information.
It i5 also noted that the prism ring or circular
refractive interface 78 may have different widths and
the angle of the surface 80 may vary as well as a
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~ 16 -
functlon of the diameter and rad-ius of curvature of the outer
concave sur:Eace 52 in re:Lation to the diameter and radius of
curvature of the inner concave surface 54~ As the angle of
surface 80 varies, the angle at ~hicl light is reflected toward
the optical center of the lens ~8 will vary along with the amount
of light (i].lumination) projected onto the retina. Other
variations such as lens material, concentricity of the outer
radius of curvature i.n relation to the inner radius of curvature
will also affect tl1e focal area of light refracted by the prism
ring. Each of these elements may be controlled in order to
direct illumination onto the most functional parts of the retina.
In fitting lenses of a system constructed in accordance
with the present invention, a standard first or magnifying lens
38, as well as a standard second or diverging lens 48, are
designed to the imaging needs of the user. A detailed
description of apparatus and method for selecting lenses is given
in app].icant's U.S. Patent No. 4,850,690, issued July 25, 1989.
The first lens can be moved forward and backward during the
fitti.ng process to effectively focus the image to the needs of
2() the patient in a manner similar to a zoom lens on a camera. When
the image being viewed is being focused to a particular patient's
needs and objects can be viewed clearly, thi.s information is used
to prepare a lens assembly. By computing the distance from the
first lens 38 to the second lens 48, times the power of the first
lens, with correct power and lens curvature, both lenses can be
secured with respect to each other to form the final lens system
or can be positioned in a frame
.. , ,i
~L3~
84-FP 8403
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assembly such as that shown in FIGS. 1-3. It is
understood ~hat for ~ome conditions tha~ the optical
axes of the patient's lenses may have to be slightly
offset from the optical axis of the eye of the patient
for proper fitting. Such may occur when the light
responsive portion of a patient's retina i8 off the
opti~al axis of the eye.
In addition to the apparatu~ a~ described above,
the present invention also includes the method of
improving the vision of a patient who is suffering
from low vision problems such as macular degeneration,
optic nerve damage or the like. The method not only
includes the steps of focusing the image being viewed,
but also includes the step of intensifying the focused
light on the macular retinal membrane which will
effectively restore vision to a user. The method
first includes the step of converging the image-
bearing light rays as they are projected from the
ob~ect 42 being viewed by the use of a positive power
lenq 38 tending to magnify the image. This lens will
also project the converged light rays tvward the eye
of the patient, the viewer. Prior to the passage of
the light rays to the eye 40 of the user, the
projected light ray~ pa~s through an air space 50 and
a second lens 48.
At the second lens 48, the received light rays
are diverged through the negative power of the second
lens 48 and such light rays are then focused onto
light responsive portions of the user's retina.
Additionally, the second lens 48 incorporates a prism
surface 78 which functions to increase the light
gathering ability of the lens system and to direct
additional light onto the user's retina. This method
84-~P-8403
- ~8 -
also include~ the step of maintaining the po~itive andnegative lense~ at a ixed ~pace from each other with
an appropriate air qpace therebetween by being held in
double frame assembly lO. The method also include~
the step of maintaining each of the lenses at a fixed
predetermined distance from the eye 40 of the user of
the apparatu~ regardles~ of the distance to the object
42 being viewed.
The present di~closure include~ that information
contained in the appended claims as well as that in
the foregoing description. Although the invention has
been described in its preferred forms or embodiments
with a certain degree of particularity, it is
understood that the present disclosure of the
preferred form~ has been made only by way of example
and that numerou8 change~ in the details of
construction, fabrication and u~e, including the
combination and arrangement of part~ and steps, may be
resorted to without departing from the spirit and
scope of the invention.
