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Патент USA US2124229

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July 19, 1938.
c. 5. FERREE ET AL
2,124,229
* CENTRAL VISION SCOTOMETER
Filed March 28, 1935‘
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CLARENCE ERROL FERREE
GERTRUDE
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RAND FERREE ‘
INVENTORS
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By’ 3414. mm '
ATTORNEY .
2,124,229
Patented July 19, 1938
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UNITED jsirAT-Eis PATENT ' pence,
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21,124,229"
" “CENTRAL VISION SOOTOMETER
. \ClareneeErrol Ferrce- and~Gertrude Rand Ferree,
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1Baltimore,.Md.
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-_ "nppliqa?tnimmh 2s, 1935;,»seriarm. 13,430 '
‘(i-Claims.
(o1. ss_20) '
The present ‘invention‘relates‘to-eye testing “tro‘ho‘f ‘intensity. ‘The'front plate 1‘5 ‘of'thei‘test
and"*more ‘particularly to 'a method -‘ and appara
tus v‘for {testing ‘for central scotomas:
The mapping, andeven the "detection of ‘small
*‘c'entral'scotomas,‘is-one of theou'tstanding ‘prob
‘lems of‘ sco‘to'me'try;
=Heretofore' "such defects
"were'ifound 'ma'in‘ly' ‘by " a "process Lof elimination
and the results “were ‘often uncertain ‘and ‘inac
curate. ‘Long and‘careiul ‘tests-‘with ‘a "tangent
‘screen, Haitz chart -'or the"»1ike’ ‘sometimes ~fail
‘entirely to revealthe'presence of small 'centra‘l
object [2, ‘the "lamp ‘ houses '1 It and ‘the support AH
‘are gpaintedfa ‘neutral gray.- ‘ '
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2' _
' The vfront plate 1‘5‘i's'fo'rmed with a ‘central ‘cir
\cularaperture Hi and four-radially disposed ‘slots
‘I’! extending‘outwardly 'from ‘said “aperture.
A
preferably White ‘disk 18 .h'aving‘ia circular aper
ture "T9 ‘is carried-by 'theplate‘i 5-‘back of-the‘ aper~
'ture [Bf-with theapertures'ilf? and -I>9Jconcentri'c. H
‘The resultant ‘form of a combination circle "and “10
‘broken cross 'forms'tanreffective control of ?xa
‘ scotoma's. Up to ithe‘presentitime there‘has‘been
Etion even though *a'e’central‘scot'oma is present.
no test for accurately and rapidly detecting the
‘IIn‘m‘aKing ‘the ‘examination the "patient is in
structed to ‘look at'the center‘ of ‘the circle'at the
*presence of a‘i‘centralf'sc‘otoma and ffor making
a rough —‘determination~of‘its size. '
'_
point of interse‘ction'o'f the "radial ‘lines and-p'the at
‘device serves to guide, and control '?'x‘ationlbyes
a‘One ‘of the objects of the present "invention ‘is
‘to ‘provide "a *‘methotb'an‘d apparatus ‘for ‘testing
‘for ‘central scotomas. 'Another "object is ‘ltoipro
tablis‘h‘ing “well “marked "lines of direction ‘which
vide -‘a vmethod ‘and apparatus ' for‘vma‘king ‘a quick
"Mounted upon the ‘support l’lv'to ‘the ‘rear of
intersect at ‘the'center of the ‘test ~v'?eld.
'
‘the‘p'l'ate l5 ande'disk i8 'is"‘a' bracket 2'0 upon 20
examination >for1‘central’scotoma and» a ‘rough "de
‘whicha‘disk 21 ‘is rotatably mounted. This ‘disk
termination -*of its size. Another-object¢is~t0!pro
vide ‘a ‘method and apparatus "for 5'-eye testing in ‘21'iis"divided=into=three sectors ‘~22 , £23 "and >24~each
which the stimulus 1fro-ma krestricted portion-“of ‘provided with three ‘apertures 25, 426 and 42-1
a test ?eld is changed without the formation of adapted "tofbe ‘moved selectively into alignment
.25 an ‘afterJimageJ IA‘ further Iobjeeti’ii-s ;to provide iwith’i'the apertures i'I'B-an-d i=9. Inone embodi
a'method and apparatus if'or i-eye-ites‘tinigrin ‘which ment “of this ‘invention the‘ size‘ of ithese Papertures
the ico’lor stimulus 'lfr'om-‘a restricted‘ portion “of are such lthatilthey ‘subten'd anglesat 'the' eye in
‘ :a test l?e'ld :ischanged iwithout ac'hanging the the ‘ratio 1:224 ‘in each sector. -"The disk 921 is
brightness lstimulus from '-said portion“ ‘These formed with nine- shallow "cups, not shown, ‘one
for each ‘aper-turaand the bracket ‘20 is ‘provided
and 1 other ‘objects and advantages ‘reside in “cer
with *a ‘spring pressed iba‘ll, *not'rs'hown, {for ‘en
tain novel ;features :of 1combination land arrange
ment iofi'pa'rts fand-lproicesses-ias will hereinafter gagem'ent ‘with said cups so as -to stop ‘the “disk '
be more :fully ‘set forthdeand»ipointedreutiin #‘the tll’lr-whenlone off'its apertures is‘in'alig'nment ‘with .
to c
appended'claims.
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‘the apertures-‘l6 and-(ISL.
"
sReferringito:tliesdrawing:
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a.
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Fig. 1 is a perspective view of an apparatustem;
vbodying $0111‘ .iinventiom.
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Fig; 2 is :a JfI‘OIIt elevation . of the ‘test ‘object.
Fig. 13 :is :a :horizontal ‘section {through the 5test
object.
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Fig. 4. is'a front J'elevatiom of the ~~aperture disk.
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Fig. 5?is'aifrontielevation ofrtheicolo-rdisk. ~
J'Anta‘pparatus=embodyingithisiinvention is illus
tratedin thee-drawing wherein if!) indicates a base
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Also rotatably ‘mounted ‘upon vithe bracket 120;:
‘to the rear‘ of the disk 2I1is‘anether’disk128 which
'is'dividedinto-eight (‘equal sectors. ' Therdis'k T8
is formed with eight shallow cups, not shown,
one‘lfor eachsecton-andthe bracket 20 is provided
with asecond‘spring pressed ball, not shown?or
engagement with-‘the'cups on dis'kl2'8 to s'top‘the
-’dis’k,when ‘one *of 1the sectors is in alignment
\withitheapertures “I’Gfand ‘I9 and» an apertures-‘in '
"disk >21.
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‘
($5
'- .upon ‘which is earri’edla‘ support 41 'ha-vin‘ga‘tes't
‘ The ei’ghtequaI sectors of the -‘ disk ‘ 28' are >=sur
object ll2iat v“one iend randian eyepiece i'I3l-at the
faced with especially prepared paints‘ and pig
other.‘ Theeyepiece k3 is zprovidediwithia pupil
.lar-y aperture of fa>size iiound‘s'to ‘,be‘ of ioptimum
ment papers in the "following 1 order: black (co
service ‘in eliminating:errorszofcrefraotion and in
ef?cient of reflection'781per cent); :gray "of ;the
igi-vingza >high ‘acuity. .‘llw‘o .vlamp. houses :14, .also
carried 'by the support 3-H ,:contain;lampsjforwsuit
approximate brightness of the ‘green ’ of ‘(the 150
ably illuminating :the-test-object 422. I The :lamp
‘houses M‘ are carefully =1ight¢proo§edkand 5are
provided with etched daylight ‘(?lters ‘for:;co1or
correction and mithneutrah?lters .iforrgress coon
e?icient of reflection 3.5‘ percent) ;' ‘white '(co
Heidelberg papers (coef?cient of re?ection 28.6
‘per cent); 1the .green of the Heidelberg ‘papers;
gray of the approximate brightness of the blue
of the :Heidelberg papers ‘(coeflicient of re?ection
.7.6;per cent) ;ithe blue .of theHei-delbeltggpapers; t5.5
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2,124,229
gray of the approximate brightness of the red
of the Heidelberg papers (coe?icient of re?ection
7.6 per cent), and the red of the Heidelberg pa
pers. The grays are approximately of the bright
ness of the colors when viewed through the small
aperture usedin the eyepiece. The disk 28 is
(4) To present at will, as the substitute for any
stimulus a neutral surface of the brightness of
the surrounding ?eld to serve as a blank for an
objective check on the correctness of the judg
ment.
In the operation and use of this apparatus, and
arranged in the manner described, so that when
the practice of this method, the patient looks
it is rotated the form and color stimuli selected
through the eyepiece I3 and ?xes his vision on
for the examination will be presented in a given
prescribed order, each preceded by its correct
preexposure. That is, the white, green, blue and
the center of the test object. By moving the disk
red sectors serve as stimuli; the grays, respec
tively, of the brightness of the green, blue and
red stimuli as preexposures for these stimuli;
15 and the black as a preexposure for the white
stimulus. As the grays are approximately of the
28, the color of the center of the test object can
be ‘changed without changing the brightness or
,_the brightness of the center of the test object
can be changed Without the introduction of
Thus,~when there is a central scotoma for
. color.
either color or form or both, either the color 15
change or the brightness change or both will be
imperceptible. The apertures 25, 26 and 21 give
scotoma for color, the stimulus tends to disap _ a rough determination of the size of the scotoma.
pear completely and the background to be seen
It will be apparent that by the use of the stimuli
as uniformly gray.
and 'preexposures named, any disturbing effects
The three, sectors 22, 23 and 24 of the disk 2|
of simultaneous or successive contrast will be
are surfaced with gray of the approximate bright
avoided. . In the use of the black and the white
ness of red and blue of the Heidelberg papers sectors, the after image ‘of the white will be black
(coe?icient of re?ection 7.6 percent) ; gray of the and vice versa so that it will not detract from the
brightness of the green of the Heidelberg papers succeeding stimulus. In the case of the colors
(coefficient of reflection 28.6. percent), and black with their preexposures, the brightness of the
,(cce?icient of re?ection 3.5 per cent) respectively. color and its preexposure are the same and the
The diameters of the three apertures 25, 26 and neutral gray preexposure does not cause an after
21 in each sector are such that the angles sub
image changing either the hue or saturation of
tended at the eye are 0.25, 0.5 and 1.0 degree re
the color. Thus the stimulus may be changed
spectively, thus giving stimuli which fall within either as to color or form without the preexposure
the ,fovea of the eye. The front vplate I5, the affecting the characteristics of the succeeding
lamp houses l4 and the support II are surfaced stimulus.
'
with the darker of the two grays used, the co
From the foregoing it will be apparent that we
ef?cient of reflection being 7.6 per cent.
are able to attain the objects of our invention
The purpose of the disk 28 is to provide a con
and provide a method and. apparatus for making
veniently operable device for the presentation of a quick examination for central scotoma and a
the color and form stimuli selected for the rough approximation of its size. The speci?c de
‘examination, the preexposures needed for these tails of construction set forth are by way of
stimuli and the blank surfaces for an objective illustration and not by Way of limitation. Various
check on the judgment. The disk 21 provides a modi?cationscan, of course, be made without
background on which the stimulus is to be viewed departing from the spirit of our invention or the
and the control of the brightness of the more im
scope of the appended claims.
mediately surrounding ?eld, and contains the
We claim:
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apertures 25, 26 and 21 needed for the gradation
1. In an apparatus of the character described,
of the size of the stimulus. The stationary front a test object comprising an apertured plate of
plate provides control of the brightness of the neutral gray shade, means for guiding ?xation
more remote surrounding ?eld and contains the toward the aperture in said plate, a second plate
device for the control of ?xation.
movably mounted behind said ?rst plate, a
same brightness as the colors, when there is a
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25
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By means of these devices it is possible:
(1) To present foveal stimuli of a great variety
of visibilities,.colo-r and form, e. g.-, red, blue‘or
green on a gray of the brightness of the color;
white on a background of black, gray of the
brightness of‘ red and blue, or gray of the bright
ness of green; gray of the brightness of green on
20
25
.30
.35
40
colored section on said second, plate, a neutral
gray section on said second plate, said gray sec
tion giving the same brightness stimulus assaid
colored section, and means for moving said
second plate to selectively bring either section
into alignment with the aperture in said aper
tured plate.
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a backgrounduof black or gray of the brightness
of red and blue, and gray of the brightness of
ired and blue ona background of black, or of gray
‘of the brightness of green. Stimuli of a great
‘variety of visibilities, color and form are thus
made available and there is provided for each
colored stimulus a background of the brightness
2. In an apparatus of the character described,
a test object‘comprising an apertured plate of‘
neutral gray shade, means for directing ?xation
toward the aperture in said plate, a second plate 60
movably mounted behind said ?rst plate, a
colored section on said second plate, a neutral
of the color, and for each form stimulus,ya back
tion giving the same brightness stimulus ‘as said
colored section, means for moving said second 65
plate to selectively bring either section into align
ment with the aperture in said apertured plate,
an eyepiece in alignment with said aperture, and
means for illuminating said test object.
3. An apparatus of the character described
comprising‘a support, a plate of a neutral shade
having a certain brightness and having a plu
ground of black or of grays of the brightness of
the
colors.
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(2) To provide for each colored stimulus a pre
exposure of the brightness of the ,color,_and for
each form stimulus, a preexposure of the bright
ness of the background, the sector serving as
preexposure, for convenience of operation, being
made to precede, in the order of rotation. of the
disk, the sector that serves as a stimulus.
(3) To present each stimulus in three sizes sub
tending at the eye angles of 0.25, 0.5‘ and 1 degree.
gray section on said second plate, said gray sec
rality of apertures of different sizes movably
mounted on said support, a second plate movably
mountedon said support, said second plate hav
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2,124,229
ing a colored portion of the same brightness as
said ?rst plate and a neutral portion of the same
teristics free from any change due to an after
brightness as said colored portion, means for se
6. An apparatus for testing central sco
toma comprising an apertured plate, a ?xation
object on said plate for directing the eye of a
patient toward said aperture, means for support
lectively moving said second plate so as to bring
one or the other of said portions into a selected
position means for selectively moving said ?rst
1 plate so as to bring any one of said apertures into
alignment with said position, and means for di
recting the eye of a patient toward said position.
4. In an apparatus of the character described,
10
a ?rst neutral gray plate having an aperture
therein, means for guiding ?xation toward the
center of said aperture, two plates movably
mounted in overlapping relation at the rear of
said ?rst plate, the front one of said two plates
being of neutral gray and having a series of ap
ertures of di?erent size concentric with the aper
ture in said ?rst plate, means for moving said
front-one of said two plates to place one of said
20 apertures in alignment with the aperture in said
?rst plate, said rear one of said two plates hav
ing a colored section and a gray section giving
the same brightness stimulus as said colored sec
tion, and means for selectively moving said rear
25 one of said two plates to bring one or the other
of said sections into alignment with said aper
tures.
5. An apparatus for testing central scotoma
comprising a neutral background, a ?xation ob
30 ject for directing the eye of a patient toward a
point in said background, a preexposure object,
' means for supporting said object at said point, a
test object, means for substituting said test object
for said preexposure object at said aperture, the
35 visual characteristics of said test object being so
related to those of the preexposure object that
the testobject appears in its true visual charac
image of the preexposure object.
ing a neutral plate at said aperture, said neutral
plate having an aperture concentric with the ap
erture of the ?rst-named plate, a preexposure ob
ject, means for supporting said preexposure ob 10
ject at the aperture of said neutral plate, a test
object having visual characteristics so related to
the visual characteristics of the preexposure ob
ject that the test object will appear in its true
visual characteristics unaffected by any after 15
image of the preexposure object, and means for
substituting the test object for the preexposure '
object.
7. An apparatus for testing central scotoma
comprising an apertured plate, a ?xation object 20
on said plate for directing the eye of a patient
toward said aperture, means for supporting a
neutral plate at said aperture, said neutral plate
having an aperture concentric with the aperture
of the ?rst-named plate, a preexposure object 25
having the same neutral brightness as said neu
tral plate, means for supporting said preexposure
‘object at the aperture of said neutral plate, a
test object having visual characteristics so re
lated to the visual characteristics of the preex 30
posure object that the test object will appear in
its true visual characteristics unaffected by any
after image of the preexposure object, and means
for substituting the test object for the preexpo
sure object.
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CLARENCE ERROL FERREE. ‘
GER'I’RUDE RAND FERREE.
35
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