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Патент USA US2124457

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July 19, 1938.
A. Am. JR., ET AL
2,124,457
TESTING EYES
Filed Oct. 25, 1934
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Patented July 119, 1938
v 2,124,451
UNITED STATES
PATENT OFFICE 1 .
2,124,457
7
TESTING EYES
Adelbert Ames, Jr., and Gordon H. Gliddon, Han
over, N. H., assignors to Trustees oi.’ Dartmouth
College, Hanover, N. H., a corporation of New
- Hampshire
Application October 25, 1934, Serial No. 749,948
5 Claims. (Cl. 88-20)
The present invention deals with lens sets
for the correcting or evaluating, especially for
testing purposes of so-called eikonic defects of
the eyes, or aniseikonia, which involve binocular
6 vision as a?ected by discrepancies of the ocular
images, the latter term being used to describe
the impression formed in the higher brain cen
ters through the vision of one eye. It is deter
mined not only by the properties of the dioptric
image that is formed in the retina of the eye,
but also by the modi?cations imposed upon that
image by the anatomical properties and physio
logical processes by which this image is carried
to the higher brain centers. .
15
Such lens sets are of particular importance
for use in connection with instruments dealt with
in our Letters Patent No. 1,944,871 of January 30,
1934 entitled “Clinical optical mensuration method
and instrument” and in Letters Patent No. 1,
20 954,399 of April 10, 1934 to Adelbert Ames, Jr.
entitled “Eye testing instrument and method”,
and in copending applications Serial Nos. 618,
200 ?led June 20, 1932 and 706,523 ?led Janu
ary 13, 1934.
allowed for when dealing with the eikonic con
ditions of a‘ patient.
Any investigation of eikonic conditions must
take into account the facts that they may vary
with varying visual distances, and that they
involve not only overall di?erences in the size
of the ocular‘ images but also so-called shape
differences the most important ones of which
are symmetric to a so-called eikonic' meridian.
Hence, the investigator should have at his dis
posal means for changing the size or shape, or
both, of ocular images by known degrees con
veniently stepped, and either the light vergence
should notbe changed, or changed to a prede
termined degree that can be easily taken into
account.
When ?rst dealing with the investigation ‘of
eikonic phenomena, we used two sets of lenses,
one for near vision (at approximately 2.5 di
opters of 40 cm.) and another one for distant
vision (at approximately 0.165 diopter or 6 m.,
which distance isv for practical purposes equiva
lent to in?nity), each set comprising a series
of spherical ‘lenses producing, at the distance
Certain terms used in the above mentioned " for which it was to be used, overall magni?cations
disclosures and in the present speci?cation and at convenient steps of approximately 25% angu N)
claims have the following meaning. “Eikonic” lar magni?cation without change of vergence,
is the term used to describe the. conditions which and another series with similar characteristics
have to do with the size and shape of the cou
30 lar image's. “Iseikonic" is that condition in which
the sizeand shape of the ocular images are
equal. “Aniseikonia” is that condition in which
the size or shape, or both, of the ocular images
are unequal. It can be divided in two types;
35 one involving overall di?‘erence, in which one
image is larger than the other in all meridians,
and another one involving meridional differences
in which one image is larger than the other in
one meridian.
40
As explained in these disclosures, tests on such
instruments comprise the measurement and com
but having cylindrical surfaces effecting meridi- onal magni?cation.
By vergence we mean the '
amount to which the light rays coming from an
object point are either diverged or converged
when entering the eye.
However, we found it rather disadvantageous
to.use two sets of lenses for the‘ two test dis
tances, mainly because of the necessary frequent,
and sometimes confusing, changes from one set
to the other. Also, the large number of lenses
renders such a trial set for eikonic tests expen
sive and bulky.
>
'
-
-
40
To overcome these and related drawbacks is
the purpose of the present invention, some of
whose objects are therefore the testing of eyes
pensation of eikonic defects with the aid of lenses
which change the» size of the ocular images,
preferably without affecting the vergence of the for 'eikonic conditions at di?‘erent visual dis- .
45 image bearing rays or, in other words, without
.tances with a single set of trial lenses, and to
optical power in the commonly used meaning of provide trial lens sets suited for testing such
that term. If such lenses, for some reason, are
not pure magni?cation lenses, they should at
least have a known power. that can be conven
60 ientlycompensated while testing, or otherwise
conditions at various distances.
‘
~
»
‘
These and other aspects and objects of our
invention will be apparent from the following
explanation describing two illustrative embodi
50
2
2,124,407
ments thereof exemplifying its genus. The de
and of the following tables being given in Fig. 5.
scription refers to drawings in which:
where R’, and R, are the radii of the surfaces of
'
Fig. 1 is a schematical drawing explaining the
a lens, and d is its thickness. ‘
terminology of the description;
TABLI I
Fig. 2_is a diagramjshowing the principle
the invention generally:
-
_
I Figs. 3 and 4 are similar diagrams giving the
data of two practical embodiments of the in
~
"
W No‘ ~
Mint
'
mm
at
‘in
mm.
n m
I
mm.
B m
0.1551)
vention;
Pindiopterl
D
mm.
_ 0.1641)
2.5D
10
Fig. 5 is a section through an individual of
10
a lens set according to the invention; and 7
Fig. 6 is a diagrammatic representation of the
compensation of residual magni?cation.
According to the invention, we use a lens set
15 whose individual lenses have at different prede
termined visual ,distances predetermined mag
ni?cations in convenient steps and, at these dis
tances, predetermined powers, which may be
zero or other values especially selected, accord
20 ing to our invention, to facilitate the evaluation
and correction of eikonic defects with the aid
1 ............. ..
0. 25
1. 21
215. 00
215. 13
0. 006
—0.'00t
0. 50
0. 75
' 1. 00
1. 25
1. 50
1. 75
1. 22
1. (ll
1. 39
95. (I)
53. 15
51. 44
94. 80
52. 89
51. 0D
0. 011
0. 018
0. 024
l. 68
1. 97
2. m
2. 55
2. 83
3. 11
3. 39
3.55
4. 18
4. 70
5. 18
5. 66
40. m
48. B5
48. 05
49. 54
48. 35
47. 45
0. 030
0. 035
0. 041
-'0. 011'
—0- 011
—0. 02!
—0. 029 ~
-0. (B5
—0 040
47. 43
45. Q3
46. 34
45. 98
45.55
44. 80
44. 27
43. 47
42. 90
46. 77
46. 21
45. 53
45. 11
44.60
43. 71
43. 04
42. 10
4].. 40
0. 048
0. 053
0. m0
0. m6
0.572
0. 084
0. 0%
0. 11B
0. 121
-0 045
--o 052
—0 068
—0 (B4
--0 m0
*0. 082
-0. 094
—0. 1m 20
-—0. 118
2. 00
2. 25
2. 50
2. 75
3.“)
3. 50
4. 00
4. 50
5. 00
of the speci?ed magni?cation properties of the
lenses.
As herein used, the terms power and magni?
25 cation are de?ned as follows, referring to Fig. 1:
If N is a point of reference, as for example the
nodal point of an eye, 0 an object, I the image of
0 produced by optical element L, a the object
distance, b the image distance, a the angle sub
30 tended at N by rays coming from the object and
p the corresponding image angle, the power P
can be expressed by
1
,
85
.
1
8
V
and the angular magni?cation
M by M=§
or in percent,
40
The above given general principle of our in
vention may be better understood by referring
to Fig. 2, which indicates, in a system of Cartesian
45 coordinates, the relations of object distance (that
is the visual distance of the test), magni?cation
and power of each lens of a series. The dis
tances are plotted in cm as abscissas, and mag
The same values for the ?rst six individuals
numbered one to six are indicated in Fig. 3 with
corresponding lens numbers used as superscripts 25
for M and P, whereby it should be noted that
the lines connecting the M and P values of any
individual for distances 1', 3, (these letters being
correspondingly applied as subscripts of M and
P) and t do not necessarily furnish correspond 80
ing values for other distances but are mainly
drawn in order to facilitate the understanding.
of the construction of the set by correlating the
data of each individual lens thereof.
The powers at 40 and 600 cm. vary so little from 35
the zero value at 74 cm., that they may be neg
lected except in some of the lenses of higher
magni?cation, above about 2%.
These lenses have been calculated by conven
tional and error ray tracing methods, ‘which 40
are familiar to anyone skilled in the art of de
signing lenses (as indicated in our Patent No.
1,933,578 of November 7, 1933) and are therefore
not repeated herein. All lenses of this example
are calculated for a distance of 23 mms. from the 45
nodal point to the front lens surface.
As mentioned before, sets for both overall and
' ni?cation M and power P as ordinates, in percent
meridional magni?cation should be provided.
The lenses of the overall magnit?cation set have
50 and diopters respectively. Thus, the individual
lenses of a set according to our invention, if, for
example, they are to be used at distances 1) and
of the corresponding meridional magni?cation
set are ground with cylindrical surfaces with the
w, (assuming for the sake of simplicity that there
are only three lens individuals, A, B, and C) have
55 at these distances predetermined magni?cations
Me, Mé’ M5’ M2! M9!’ Mel
and selected powers
60
P6. P5, P5, P3. P9. P5
the above data in every meridian, whereas those 50
curves given in Table I in one meridian and
plano clurves in the meridian perpendicular
thereto.
When these meridional size lenses are used for
tests at 40 cm. visual distance, they produce a
certain magni?cation in the zero curvature me
ridian perpendicular to the meridian having the
speci?ed magni?cation, which magni?cation may 60
The relation of magni?cations and powers of
the lens individuals should be chosen to suit prac
be referred to as “residual” and can not always a
tical requirements at hand, and two examples of
it can be compensated by placing before the other
lens sets according ‘to our invention, which we
65 have found especially suitable for the tests above
referred to, will now be given.
In the example graphically shown in Fig. 3, the
magni?cations are graded in similar steps of
0.25%, from zero to 5%.
The powers are so cal
70 culated that all lens individuals have zero power
at an intermediate distance t of approximately
74 cm. (1.35 D), which results at r=40 cm. (read
ing distance) and at s=600 cm. (practically equiv
alent to in?nite) in powers of values given in the
75 following Table I, the terminology of this table
be neglected. We have found, however, that
eye an auxiliary lens which has the residual mag
ni?cation in a meridian placed parallel to the
zero curvature meridian of the main lens, and
zero magni?cation in the meridian perpendicular
thereto. This arrangement is shown in Fig. 6,- ‘
where a meridional size defect of 0.75 of the right
eye is indicated as corrected by a lens No. 3 which, 70
however, has a residual magni?cation in the
meridian perpendicular to the corrected merid
ian. This residual magni?cation is compensated
by means of a No. 1 lens before the left eye, which
lens has a compensating magni?cation in the me
75
0,124,401
ridian of the residual magni?cation and no mag
ni?cation in the meridian perpendicular thereto.
It is not necessary to have an auxiliary com
pensating lens for each lens of the meridional
sets, but one auxiliary lens can be used for a
group of meridional test lenses.‘ Table II below
Tun: III
Overall magni?cation‘ '1
gives the characteristics of an auxiliary set suit-
able for use with the trial set of Table I.
Lens No.
If desired, the power of the lenses of higher
magni?cation can be compensated with'an aux-
Min
Min
P
Ii
33;
a’;
25% $111.
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enses
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$13,920,, - dinmm, R‘mmm
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compensated.
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1.331
332.313
00 03. 53
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1.50 -0.00
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3.30
.
1.50
22"
10.50
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2.00 -0.10 2.35
30.55
2.15-
2.50
2.334
332.313
330.203
4.111
332.313 330.203
5.113
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-
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513.15
2”
11.51
2.25
330.203
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2.25
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10
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.
the powers listed. in Table I‘,1 preferably only for
15
.
13min
‘
iliary lens set comprising lens individuals having
m" ‘mes ‘m N“ 1”“;
. '...
0.50
‘
35"
35.11
6.50
-0.11-
2.34
40.21
30.20
-0.12
3.35
43.24
42.12
-
-
31-91
35-96
30-"
34-46
--
-
2%
"3'18 3'23
‘12° 4-
20
330.203
25
so iii
TABLI: IV
Meridional lenses
Lens No.
45
M in %.d m 155;":
0.25
3.51
533.13
0.50
0.15
305.13 v306.38
232.44 233.00
1.00
1.25
1.50
4.23
4.30
2.53
3.23
3.31
- 1.15
2.00
2.25
2.50
2.15
3.00
3.50
4.00
It will ‘now be evident that a lens set of this
our invention is preferable.
65
This second example, graphically indicated in
-0.020 ax 0lmag___ 0.25s
0.250
—0.03C axoimag---0.040 ax oimag-..
0.31s
0.310
0.370
0.020
00.33
01.05
01.20
-0.050 ax oimag--.
—-0.06Caxoimag___
-0.010 axoimag__.
0.253
0.253
0.313
0.150
1.000
1.120
4.52
00.00
01.40
-0.030 axoimag.--
0.31s
1.310
2.41
3.10
3.10
4.43
2.44
3.34
5.25
41.66
41.03
52.51
50.40
23.00
31.01
45.41
42.47
43.11
53.10
51.04
23.33
30.10
41.10
—0.090 axoimag___
4.100511011111111...
-0.110 ax oimag...
—-0.12Caxo(mag-__
-0.130 ax olmag___
-0.150 8}! ofmag--_0.130 ax ol‘mag__-
0.255
0.25s
0.31s
0.31s
0.253
0.310
0.503
1.500
1.150
1.310
2.120
2.250
2.020 40
3.000
ing designed for a distance of 40 mms. from nodal
point to front lens surface, and the meridional
lenses for a corresponding distance of 45 mms.
When this set is employed, the clinician can
use its individuals for tests at the visual distance
of 600 cm. without consideration of any power
e?ect. When performing near'vision tests, he
takes into account even power values which may
be listed in a table or marked on the lens handles.
No compensating lenses are necessary with the
meridional lenses when used for distance vision,
whereas for near vision, a residual magni?cation
may be compensated as explained above for the
?rst example.
-
affected by dioptric power effects, the ocular im
spectively: '
60
It should be understood that the present dis
closure is for the purpose of illustration only
and that this invention includes all modi?cations
and equivalents which fall within the scope of
tances, but where the magni?cations for both dis
set of this type are given below in Tables III and
IV, for spherical and cylindrical lens sets, re
35
ventional methods, the spherical individuals be
the appended claims.
We claim:
zero for one distance and for the other distance
stepped in even steps. The characteristics of a
30
00.00
00.00
00.00
Fig. 4 in a manner ‘quite similar to that used in
Fig. 3, is a lens set where each lens is not de?ned
as producing equal magni?cations at two dis
70 tances may vary in even steps, with the powers
76
534.22
1
These lens data have also been obtained by con
type can well be used for evaluating magni?ca
tions at two different distances, it being com
paratively simple to take into account ‘the powers
for magni?cations higher than approximately
2%, which magni?cations do not occur very fre
quently, and to compensate meridional lenses as
explained above. It will be understood that
these power values and the auxiliary magni?ca
tion lenses can be easily listed in simple tables
for ready reference or indicated on the handles
of the respective individuals.
If, however, itis less desirable to have the same
magni?cation at the two distances, but prefer
60 able to simplify the accounting for power and to
have no residual magni?cation in the meridional
set for one distance, the following embodiment of
Dioptrie properties at 2.5D
-
l. A set of lenses for testing, substantially un
age size properties of eyes for two object dis- -
tances, one for near and one for distant vision,
by placing before the respective eyes trial lenses
in holders substantially determining the distances
of said lenses from the respective eye, comprising
a series of principal trial lens elements each hav
ing a thickness, and surfaces with curvatures in 75
4-
2,124,457
one meridian to produce a lens eifecting' in said ‘having a thickness, and surfaces with curvatures
meridian at said distances certain magni?cations in one meridian to, produce a lens effecting in
and for certain object distances certain dloptric said meridian at said distances certain magni?
powers, the elements of said series having for cations‘and for certain object distances certain
_,said two object distances, respectively, magni?
dioptric powers, the elements of said series hav
cations stepped in certain prescription magni?
ing for said two object distances magni?cation
cation values, having for at least one or said two
'10
object distances comparatively small dioptric
powers stepped in certain prescription power
values, and all elements having for a certain ob
ject distance zero, dioptric power, and a series of
auxiliary trial power lens elements each having
values equal for each element but stepped for
different elements in certain prescription mag:
nl?cation values, having for at least one of said
two object distances comparatively small diop 10
tric' powers stepped in certain prescription power
values, and all elements having for a certain ob
a thickness and surfaces with curvatures in one v ject distance zero dioptric power; and a series of
meridian to produce a lens effecting for one of auxiliary trial power lens elements each having
said two object distances a dioptric power sub
a thickness and surfaces‘ with curvatures in one
stantially equal and opposite to the power of a meridian to produce a lens effecting for one oi’
corresponding element of said principal series,
said di?erent object distances a dioptric power
whereby an auxiliary element is to be placed in '
substantially equal and opposite to the power of
said holders in alignment with a principal ele
a corresponding element of said principal series,
whereby an auxiliary element is to be placed in 20
said holders in alignment with a principal ele
ment of equal but opposite power.
ment of equal but opposite power.
'
2. A set of lenses for testing, substantially un
affected by dioptric power effects, the ocular im
age size properties of eyes for two object dis- '
4. A set of lenses for testing, substantially un
tances, one for near and one for distant vision,
affected by dioptric power effects, the ocular
image size properties of eyes ‘for two object dis
by placing before the respective eyes trial lenses
in holders substantially determining the distances _ tances, one for near and one for distant vision, by
of said lenses from the respective eye, compris
ing a series of principal trial lens elements each
placing before the respective eyes trial lenses in
holders substantially determining the distances
having a thickness, and surfaces with curvatures , of said lenses from the respective eye, compris
in one meridian and with different curvatures in ing a series of trial lens element each having a, 30
a meridian normal thereto, to produce a cylindri
cal lens effecting in said ?rst meridian at said
distances certain magni?cations and for certain
object distances certain dioptric powers, the ele
ments of said series having in said ?rst meridian
for said two object distances magni?cations
stepped in certain prescription magni?cation
thickness, and surfaces with curvatures in one
meridian to produce a lens effecting in said me
ridian at said distances certain magni?cations,
and for certain object distances certain dioptric
powers, the elements of said series having for said
two object‘distances magni?cations stepped in
certain prescription magni?cation values, and
having for one of said object distances zero diop
values, and all elements having in said ?rst merid
n
ian for a certain object distance zero dioptric tric power. '
5. A set of lenses for testing, substantially un 40
power, and effecting for at least one of said two
object distances in said second meridian zero affected by dioptric power effects, the ocular im
power and certain residual magni?cations; and age size properties of eyes for two object dis
a series of auxiliary trial lens elements each hav »tances, one for near and one for distant vision, by
placing before the respective eyes ‘trial lenses in
ing a thickness and surfaces having in two nor
mal meridians curvatures to produce a cylindrical holders substantially determining the distances of
lens e?ecting in one meridian a magni?cation, , said lenses from the respective eye, comprising a
substantially equal to said residual magni?cation series of trial lens elements each having a thick
of a corresponding element of said principal se
ries, and having in the other meridian substan
tially
zero magni?cation, whereby any one princi
50
. pal element is to be used before one eye with an
auxiliary lens of equal residual magni?cation be
fore the other eye.
-_
3. A set of lenses for testing, substantially un
affected by dioptric power eifects, the ocular im
age size- properties of eyes for two object dis
tances, one for near and one for distant vision,
by placing before the respective eyes trial lenses
in holders substantially determining the distances
of said lenses from the respective eye, compris
ing a series of principal trial lens elements each
ness, and surfaces'with curvatures in one merid
ian to produce a lens effecting in said meridian
at said distances certain magni?cations, and for
certain object distances certain dioptric powers,
the elements of said series having for said two
object distances magni?cations stepped in certain
prescription magni?cation values, having for one
of said two object distances zero dioptric power,
and for the other of said two object distances
dioptric powers stepped in certain prescription
power values.
ADELBERT AMES, JR.
GORDON H. GLIDDON.
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