Improvements in Instruments for Determining Errors of Refraction in the Eye.
Year: 1894

page_text: Date of Application, 6th Jan., 1894
Complete Specification Left, 8th Oct., 1894-Accepted, 1st Dec. 1894
PROVISIONAL SPECIFICATION.
Improvements in Instruments for Determining Errors of Refraction
in the Eye.
I SAMUEL HARDY of 19 Charterhouse Street in the City of London Wholesale
Jeweller do hereby declare the nature of this invention a communication to me
from abroad by Alfred Clarke of 13 Hunter Street Sydney in the Colony of New
South Wales, Optician, to be as follows:-
The invention relates to improvements in instruments for determining errors of
refraction in the eye and has for its object to obtain a simple, inexpensive, and
efficient means of manipulating and combining certain lenses in the line of sight in
the manner necessary for the desired test.
The lenses employed in instruments of this character are ordinarily of two kinds
namely spherical and cylindrical and the present invention will for convenience be
described in connection with lenses of that character.
In carrying the invention into effect the spherical lenses are mounted-in the
manner commonly followed in instruments of a like nature-in a circle of apertures
arranged around a disc near to the periphery thereof the disc being fixed upon a
shaft or axis mounted with capability of revolution in a suitable bearing carried
by a standard or upright.
The standard is at its upper part constructed with lateral horizontal arms which
together with the standard form a T shape and the bearing for the shaft of the
spherical lens disc is formed in a boss located at the junction of the standard and
horizontal arms.
At the end of each horizontal arm is provided a circular aperture so arranged
that as the spherical lens disc is revolved the lens apertures therein will coincide
in succession with the circular apertures in the horizontal arms of the standard.
The horizontal arms form a rest or support against which the forehead of a
patient may be steadied with that eye whose refraction it is desired to determine
opposite the aperture in the corresponding horizontal arm so that upon the
spherical lens disc being revolved upon its axis the spherical leuses carried thereby
can be brought before the eye in rapid succession.
In order to carry and facilitate the manipulation of the cylindrical lenses the
following arrangement of parts is employed.
The lower end of the standard is enlarged to form a boss in which is formed a
orizontal bearing arranged at right angles or perpendicular to the horizontal
rms, and in this bearing is mounted with capability of revolution a shaft upon
which is fixed the lower end of a radius arm the parts being so arranged that the
pper end of this arm is adapted to traverse the spherical lens disc from side to
ide in either direction.
The upper end of this radius arm is provided with an apertured boss which
orms a bearing for the purpose hereinafter described and the radius arm may
hen required be temporarily fixed in such position that the centre of this bearing
o-incides with the centre of either of the apertures at the ends of the horizontal
rins of the standard.
The cylindrical lenses are mounted in apertures arranged in a circle around a
isc in a similar manner to that herein before describad ith respect to the

page_text: spherical lenses and this cylindrical lens disc is axially provided with a shaft
which is mounted in a corresponding bearing formed in a circular plate or disc
carrier so that the cylindrical lens disc can be revolved with relation to the disc
carrier.
Upon the front of the disc carrier and near to its circumference is formed an
aperture corresponding with one of the ring of apertures in the cylindrical lens
disc so that as the cylindrical lens disc is rotated over the disc carrier each
cylindrical lens in the circle will successively pass centrally before the aperture
of the disc carrier.
Upon the face of the disc carrier and surrounding the aperture is formed or fixed
an apertured boss the outer surface of which is turned to form a shaft which is
mounted in the bearing formed in the upper end of the radius arm hereinbefore
described.
By the peculiar arrangement of parts hereinbefore described the cylindrical lens
disc can be rotated so as to bring all the lenses in succession before the aperture
or boss of the disc carrier and by rotating the disc carrier with its boss as the
centre of rotation in the bearing at the upper end of the radius arm any cylindrical
disc of the circle which is before the aperture or boss of the disc carrier and
therefore before the eye of the patient will be revolved around its own axis.
The axis of this cylindrical lens which is before the eye can thus be inclined at
any angle without the employment of toothed gearing or other devices.
Furthermore if the cylindrical lenses are mounted in their disc in a uniform
position as regards the direction of their axes they will each assume the same
axial direction as they are successively brought by the rotation of their disc in
front of the aperture and boss of the disc carrier.
By these means any particular cylindrical lens can be placed in any axial
inclination and in combination with any particular spherical lens and opposite
the aperture in either horizontal arm of the standard.
Dated this 6th day of January 1894.
WHITE & WOODINGTON,
27, Southampton Buildings, London, Agents.
COMPLETE
SPECIFICATION.
Improvements in Instruments for Determining Errors of Refraction
in the Eye.
I SAMUEL HARDY of 19 Charterhouse Street in the City of London, Wholesale
Jeweller do hereby declare the nature of this invention a communication to me
from abroad by Alfred Clarke of 13 Hunter Street Sydney in the Colony of New
South Wales, Optician and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
The invention relates to improvements in instruments for determining errors of
refraction in the eye and has for its object to obtain a simple, inexpensive and
efficient means of manipulating and combining certain lenses in the line of sight in
the manner necessary for the desired test.
The lenses employed in instruments of this character are ordinarily of two kinds
namely spherical and cylindrical and the present invention will for convenience be
described in connection with lenses of that character.
In carrying the invention into effect the spherical lenses are mounted-in the
manner commonly followed in instruments of a like nature-nainely in a circle of
apertures arranged around a disc to the periphery thereof the disc being fixed
upon a shaft or axis mounted with capability of revolution in a suitable bearing
cirried by a standard or upright.

page_text: The standard is at its upper part constructed with lateral horizontal arms
which together with the standard form a T shape and the bearing for the shaft
of the spherical lens disc is formed in a boss located at the junction of the standard
and horizontal arms.
At the end of each horizontal arm is provided a circular aperture so arranged
that as the spherical lens disc is revolved the lens apertures therein will coincide
in succession with the circular apertures in the horizontal arms of the standard.
The horizontal arms form a rest or support against which the forehead of a
patient may be steadied with that eye whose refraction it is desired to determine
opposite the aperture in the corresponding horizontal arm so that upon the spherical
lens disc being revolved upon its axis the spherical lenses carried thereby can be
brought before the eye in rapid succession.
In order to carry and facilitate the manipulation of the cylindrical lenses the
following arrangement of parts is employed.
The lower end of the standard is enlarged to form a boss in which is formed a
horizontal bearing arranged at right angles or perpendicular to the horizontal arms
and in this bearing is mounted with capability of revolution, a shaft upon which
is fixed the lower end of a radius arm the patts being so arranged that the upper
end of this art is adapted to traverse the spherical lens disc from side to side in
either direction.
The upper end of this radius arm is provided with an apertured boss which
forms a bearing for the purpose hereinafter described and the radius arm may
when required be temporarily fixed in such position that the centre of this bearing
coincides with the centre of either of the apertures at the ends of the horizontal
arms of the standard.
The cylindrical lenses are mounted in apertures arranged in a circle around a
disc in a similar manner to that herein before described with respect to the
spherical lenses and this cylindrical lens disc is axially provided with a shaft which
is mounted in a corresponding bearing formed in a circular plate or disc carrier so
that the cylindrical lens disc can be revolved with relation to the disc carrier.
In the disc carrier and near to its circumference is formed an aperture
corresponding with one of the ring of apertures in the cylindrical lens disc so that
as the cylindrical lens disc is rotated over the disc carrier each cylindrical lens in
the circle will successively pass centrally before the aperture of the disc carrier.
Upon the face of the disc carrier and surrounding the aperture is formed or
fixed an apertured boss the outer surface of which is turned to form a shaft
which is mounted in the bearing formed in the upper end of the radius arm
hereinbefore described.
By the peculiar arrangement of parts hereinbefore described the cylindrical lens
disc can be rotated so as to bring all the lenses in succession before the aperture
or boss of the disc carrier and by rotating the disc carrier with its boss as the
centre of rotation in the bearing at the upper end of the radius arm any
cylindrical lens of the circle which is before the aperture or boss of the disc
carrier and therefore before the eye of the patient will be revolved around its
own axis.
The axis of the cylindrical lens which is before the eye can thus be inclined
at any angle without the employment of toothed gearing or other devices.
Furthermore if the cylindrical lenses are mounted in their disc in a uniform
position as regards the direction of their axes they will each assume the same axial
direction as they are successively brought by the rotation of their disc in front of
the aperture and boss of the disc carrier.
By these means any particular cylindrical lens can be placed in any axial
inclination and in combination with any particular spherical lens and opposite the
aperture in either horizontal arm of the standard.
And in order that the said invention may be more clearly understood and
readily carried into effect, I will proceed aided by the accompanying drawings
more fully to describe the same.

page_text: Figure 1 is a front elevation of an instrument constructed according to the
present invention.
Figure 2 is a side elevation thereof.
Figure 3 is a rear elevation thereof.
Figure 4 is a vertical transverse section taken on the line 1-1 of Figure 1.
Figure 4 is a horizontal section of part of the instrument.
Figure 5 is a rear elevation of the spherical lens disc separately.
Figure 6 is an edge view thereof.
Figure 7 is a front elevation of the cylindrical lens disc separately.
Figure 8 is an edge view thereof.
Figure 9 is a front elevation of the disc carrier, and
Figure 10 is an edge view thereof.
Figure 11 is a front elevation of a complete instrument embodying some slight
modifications, and drawn to a slightly increased scale.
Figure 12 is a side elevation thereof partly in section.
In the several figures like parts are indicated by similar letters of reference.
Referring to Figures 1 to 10 a represents the spherical lens disc which near to
the periphery thereof is provided with a circle of apertures a¹, in which are
mounted the spherical lenses, and this disc a is fixed upon a shaft or axis a
mounted with capability of revolution in a bearing 61* carried by a standard or
upright b.
The standard bis at its upper part constructed with lateral horizontal arms b
which together with the standard 6 form a T shape, and the bearing for the
shaft a² of the spherical lens disc a is formed in a boss b' located at the junction
of the standard 6 and horizontal arms b².
At the end of each horizontal arm & is provided a circular aperture * so
arranged that as the spherical lens disc a is revolved the lens apertures a' therein
will coincide in succession with the circular apertures 2* in the horizontal arms b
of the standard b.
The horizontal arms 62 form a rest or support against which the forehead of a
patient may be steadied, with that eye, whose refraction it is desired to determine
opposite the aperture 62* in the corresponding horizontal arm 6' so that upon the
spherical lens disc a being revolved upon its axis a³, the spherical lenses carried
thereby can be brought before the eye in rapid succession.
In order to carry and facilitate the manipulation of the cylindrical lenses, the
following arrangement of parts is employed.
The lower end of the standard b is enlarged to form a boss 63 in which is formed
a horizontal bore or bearing arranged at right angles or perpendicular to the
horizontal arms and in this bearing is mounted with capability of revolution a
shaft c¹ upon which is fixed the lower end of a radius arm c the parts being so
arranged that the upper end of the radius arm c is adapted to traverse the spherical
lens disc a from side to side in either direction.
The upper end of the radius arm c is provided with an apertured boss c which
forms a bearing for the purpose hereinafter described and the radius arm c may
when required by means of a pin c* entering a hole formed in the standard band
engaging one of two notches formed in the lower end of the radius arm c be
temporarily fixed in such position that the centre of the bearing in the boss c²
coincides with the centre of either of the apertures 6 at the ends of the horizontal
arms of the standard b.
The cylindrical lenses are mounted in apertures d'arranged in a circle around a
disc d in a similar manner to that herein before described with respect to the
spherical lenses, and this cylindrical lens disc d is axially provided with an
aperture threaded to receive the screwed end of a stud or shaft 2 which is
mounted in a bearing 2 formed in a circular plate or disc carrier e so that the
cylindrical lens disc d can be revolved with relation to the disc carrier e.

page_text: In the disc carrier e and near to its circumference is formed an aperture e¹
corresponding with one of the ring of apertures d' in the cylindrical lens disc d so
that as the cylindrical lens disc d is rotated over the disc carrier e each cylindrical
lens in the circle will successively pass centrally before the aperture e¹ of the disc
carrier e.
Upon the face of the disc carrier e and surrounding the aperture el is formed or
fixed an apertured boss the outer surface or circumference of which is turned to
form a shaft or axis which is mounted in the bearings formed in the boss c* at the
upper end of the radius arm c as hereinbefore described.
°
By the peculiar arrangement of parts hereinbefore described the cylindrical lens
disc d can be rotated so as to bring all the cylindrical lenses in succession before
the aperture e and apertured boss e¹ of the disc carrier e and by rotating the disc
carrier e with its boss elo as the centre of rotation in the bearing in the boss cat
the upper end of the radius arm c any cylindrical lens of the circle which is before
the aperture e¹ and boss e¹* of the disc carrier e and therefore before the eye
of the patient will be revolved around its own axis.
The axis of the cylindrical lens which is before the eye of the patient can thus
be inclined at any angle without the employment of toothed gearing or other
devices; furthermore if the cylindrical lenses are mounted in their disc din a
uniform position as regards the direction of their axes, they will each assume the
same axial direction as they are successively brought by the rotation of their disc d
in front of the aperture e¹ and boss e¹* of the disc carrier e.
The spherical lens disc a is provided with a circle of numbers identifying the
lenses carried in the apertures a¹ and the cylindrical lens disc d is similarly
provided with a circle of indications which latter are exposed in the desired
order at a notch or aperture 3 in the disc carrier e as shown more particularly at
Figure 1.
By these means any particular cylindrical lens of the apertures a' can be placed
in any axial inclination, and in combination with any particular spherical lens of
the apertures a¹ and opposite the aperture 62* in either horizontal arm b' of the
standard b.
In the example given at Figures 11 and 12 the device is identical in principle
with that hereinbefore described, but some of the details of construction are
slightly improved.
In this case the boss elo of the disc carrier e has fixed therewith by a key or
feather a collar e* which forms the shaft or axis revolving in the bearing in
the boss of the radius arm c and the face of the boss c of the radius arm c is
marked with a graduated scale whilst the face of the loose collar e* is marked
with two arrows by the aid of which the inclination of the axis of the cylindrical
lens before the eye at any moment can be ascertained, whilst in order to temporarily
fix the disc carrier e in the desired position a pin or detent c³ is fixed upon a
spring thumb lever c* and engages a circle of notches or recesses *** formed in the
collar e**.
The spherical lens disc a is also adapted to be temporarily locked in the desired
position by means of a spring bolt 6* carried by the standard b6 and engaging a
circle of indents or recesses a in the spherical lens disc a whilst a similar bolt e**
carried by the disc carrier e engages à corresponding circle of indents do in the
cylindrical lens disc d with the same object.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In an instrument of the character herein referred to the combination of a
Tshaped staud and a radius arm at its inner end pivotally mounted upon the stand
so that its outer end is adapted to be traversed from one extremity of the horizontal
limbs of the T to the other extremity thereof substantially as herein shown and
described and for the purpose stated.

page_text: 2. In an instrument of the character herein referred to the combination of a
disc mounted upon a stand with capability of rotation and carrying a circle of
lenses arranged around its circumference a radius arm at its inner end pivotally
mounted on the stand and at its outer end adapted to traverse the lens disc, a disc
carrier eccentrically mounted with capability of rotation upon the outer end of the
radius arm and a second lens disc concentrically mounted with capability of
rotation upon the disc carrier substantially as herein shown and described and for
the purpose stated.
3. In an instrument of the character herein referred to the combination of a
Tshaped stand provided with apertures at the ends of its horizontal limbs, a disc
mounted upon the stand with capability of rotations and carrying a circle of lenses
intersecting or corresponding with the apertures of horizontal limbs, a radius arm
at its inner end pivotally mounted in the stand and at its outer end formed with an
apertured boss adapted to traverse the lens disc from side to side so that in either
of its extreme positions its aperture will coincide with one of the apertures of the
horizontal limbs of the stand a disc carrier provided with an eccentrically disposed
apertured boss pivotally mounted in the apertured boss of the radius arm and a
second disc furnished with a circle of lenses and concentrically mounted with
capability of rotation upon the disc carrier in such manner that the circle of lenses
intersects or corresponds with the apertured boss of the radius arm substantially
as herein shown and described and for the purpose stated.
Dated this 8th day of October 1894.
WHITE & WOODINGTON,
27, Southampton Buildings, London, Agents.