Improvements in or connected with Sight-testing Apparatus.
Year: 1895

page_text: Date of Application, 4th Oct., 1895
Complete Specification Left, 6th July, 1896-Accepted, 8th Aug., 1896
PROVISIONAL SPECIFICATION.
Improvements in or connected with Sight-testing Apparatus.
I, BRUCE GREEN, of Nos. 65, and 66, Chancery Lane, in the County of
London, Gentleman, do hereby declare the nature of this invention to be as
follows:-
:-
This invention relates to improvements in or connected with sight-testing
apparatus, and has for its object to obtain a simple form of apparatus, by the aid of
which a person may test his sight in respect of an object such as printing arranged
within the apparatus at a fixed distance or alternatively may view some distant
building or other object for the same purpose.
In carrying the invention into effect, a box or case is employed which may be
rectangular in form, and within this box or case and transversely thereof are
arranged four supporting rollers, two being in a vertical plane or nearly so at the
front of the case, and two at the rear thereof.
These rollers are mounted with capability of revolving upon suitable axes and
are rectangular in shape in cross section, whilst the axis of one of them projects
through the side of the box or case, and is provided with a milled button by the
aid of which it may be turned at the times desired.
Around these supporting rollers is arranged an endless belt of plates which may
be of metal and are each of the same area as one of the flats or sides of the
supporting rollers and in each of these plates are mounted a pair of lenses, each
pair being of different power whilst in the front of the box or case are arranged
two eye-pieces so that by rotating the milled button the endless belt of lenses may
be traversed so as to bring each pair of lenses in succession into alignment with
the eye-pieces and the operator is thus enabled to view the printed numbers or
other test which is exhibited upon a tablet at the rear of the box or case but
within the endless belt, and thereby test his sight in respect of each power of each
of the lenses carried by the endless belt.
In order to display the test number, the tablet is formed with an aperture therein
and the plates which pass around the same have each marked upon the inner or
reverse side thereof a printed number arranged so that each number in turn is
exhibited through the aperture in the tablet and the test numbers are so arranged
that each number exhibited corresponds with and indicates the power of the
particular pair of lenses at that time coincident with the eye-pieces and in the line
of sight.
In order to afford a test for long distance, one side of the box is provided with a
glass window, whilst near to the tablet upon which the printed test is mounted is
provided a mirror or sheet of looking glass, which is arranged at such an angle as
to receive through the glass window or side of the box or case the image of a
building or other distant object and enable the same to be viewed by the operator
looking through the eye-pieces, so that by varying the position of the box or case
in order to reflect in the looking glass or mirror different objects located at
different distances from the apparatus, the operator may thoroughly test the
condition of his sight.
In some cases, it is desirable to test each eye independently, and, for this
purpose, each one of a pair of lenses is mounted in a separate endless belt of plates
supported upon a separate set of rollers independently mounted and in this case

page_text: one roller of each belt is provided with a milled buttou or like means for
actuating the belt, whilst a separate test number is marked upon the rear
side of each plate and the object tablet is provided with two corresponding
apertures.
Dated this 4th day of October 1895.
improvements in or connected with Sight-testing Apparatus.
I, BRUCE GREEN, of Nos. 65, and 66, Chancery Lane, in the County of
London, Gentleman, do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
My said invention relates to improvements in or connected with sight-testing
apparatus, and has for its object to obtain a simple form of apparatus, by the
aid of which a person may test his sight in respect of an object such as printing
arranged within the apparatus at a fixed distance or alternatively may view some
distant building or other object for the same purpose.
In carrying the invention into effect, a box or case is employed which may be
rectangular in form, and within this box or case and transversely thereof are
arranged four supporting rollers, two being in a vertical plane or nearly so at
the front of the case; and two at the rear thereof.
These. rollers are mounted with capability of revolving upon suitable axes and
are rectangular in shape in cross section, whilst the axis of one of them projects
through the side of the box or case, and is provided with a milled button by the
aid of which it may be turned at the times desired.
Around these supporting rollers is arranged an endless belt of plates which may
be of metal and are each of the same area as one of the flats or sides of the
supporting rollers and in each of these plates are mounted a pair of lenses, each
pair being of different power whilst in the front of the box or case are arranged
two eye-pieces so that by rotating the milled button the endless belt of lenses may
be traversed so as to bring each pair of lenses in succession into alignment with
the eye-pieces and the operator is thus enabled to view the printed numbers or
other test which is exhibited upon a tablet at the rear of the box or case but
within the endless belt, and thereby test his sight in respect of each power of each
of the lenses carried by the endless belt.
In order to display the test number, the tablet is formed with an aperture therein
and the plates which pass around the same have each marked upon the inner or
reverse side thereof a printed number arranged so that each number in turn is
exhibited through the aperture in the tablet and the test numbers are so arranged
that each number exhibited corresponds with and indicates the power of the
particular pair of lenses at that time coincident with the eye-pieces and in the line
of sight.
In order to afford a test for long distance, one side of the box is provided with
a glass window, whilst near to the tablet upon which the printed test is mounted is
provided a mirrow or sheet of looking glass, which is arranged at such an angle as to
receive through the glass window or side of the box or case the image of a building
or other distant object and enable the same to be viewed by the operator looking
through the eye-pieces, so that by varying the position of the box or case in
order to reflect in the looking glass or mirror different objects located at different
distances from the apparatus, the operator may thoroughly test the condition of
his sight.

page_text: In some cases, it is desirable to test each eye independently, and, for this
purpose, each one of a pair of lenses is mounted in a separate endless belt of
plates supported upon a separate set of rollers independently mounted, and, in
this case, one roller of each belt is provided with a milled button or like
means for actuating the belt, whilst a separate test number is marked upon the
rear side of each plate and the object table is provided with two corresponding
apertures.
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.
the present invention.
Figure 2 is a vertical longitudinal section thereof.
Figure 3. is a vertical transverse section thereof looking from the rear of the
apparatus.
Figure 4.
a horizontal section thereof, and,
Figure 5. is a similar view to Figure 4, but illustrating a slight modification.
In the several figures like parts are indicated by similar letters of reference.
Referring to Figures 1. to 4., a. represents a box or case formed of wood or
other suitable material and generally rectangular in shape but with a sloping front
and preferably furnished with a door (not shown) controlled by a lock and key,
and within the box or case a. and transversely thereof are arranged four supporting
rollers b. two being in a vertical plane or nearly so at the front of the case or box a.
and two at the rear thereof.
These rollers b. are fixed upon suitable shafts or axes 6' mounted with capability
of revolving in bearings a¹ in the side of the box or case a. and the rollers b. are
formed rectangular in shape in cross section whilst the shaft or axis 61 of one of such
rollers projects through the side of the box or case a. and is provided with a milled
button 2 by the aid of which it may be turned at the times desired for the purpose
hereinafter described.
C.
may
Around these supporting rollers b. is arranged an endless belt of plates c.
connected together by links c and these plates which
be of metal are each
of the same width as one of the flats or sides of the supporting rollers b. or
thereabout so that a quarter revolution of the milled button 62 will advance the
endless belt c. the distance of one plate.
In apertures in each of the plates c. of the endless belt are mounted a pair of
lenses each pair being of different power whilst in a suitable position in the
sloping front of the box or case a. are arranged two eye-pieces d. so that by rotating
the milled button 2 the endless belt of lenses may be traversed and thereby bring
each pair thereof in succession into alignment with the eye-pieces d. and the
operator is thus enabled to view the printed matter or other test which is exhibited
upon a tablet e' carried by a screen e. at the rear of the box or case but located
within the endless belt c. and thereby test his sight in respect of the power of each
pair of lenses c² carried by the endless belt c.
In order to enable a person using the instrument to identify the lenses best
suited to his sight, the screen c. is formed with an aperture therein and the
plates c. which pass around the same have each marked upon the inner or reverse
side thereof a printed index number c arranged so that each number in turn
is exhibited through the aperture e in the screen e. and these index numbers c³
are so arranged that cach number so exhibited at the aperture e corresponds with
and indicates the power of or identifies the particular pair of lenses (2 at that time
coincident with the eye-pieces d.
In order to afford a test for long distance, one side of the box or case a, is

page_text: provided with a glass window a², whilst near to the tablet e' upon which the printed
test matter is mounted, is provided a mirror or sheet of looking-glass e³ which is
carried by the screen e. and is arranged at such an angle as to receive through the
glass window a² at the side of the box or case a. the image of a building or other
distant object and enable the same to be viewed by the operator looking through
the eye-pieces d. so that by varying the position of the box or case a. in order to
reflect in the looking-glass or mirror e different objects located at different
distances from the apparatus, the operator may thoroughly test the condition of
his sight.
In the example given at Figure 5., a modified form of apparatus is shown which
permits of each eye being tested independently, and, for this purpose, each one of
a pair of lenses c² is mounted in a separate endless belt of plates c. supported
upon a separate set of rollers b. independently mounted, that is to say, three pairs
of the rollers b. are loosely mounted so as to revolve around their shafts b¹
whilst the fourth pair of rollers b. are fixed with their shafts 161 each of which
shafts is mounted with capability of revolving in bearings in the walls of the case a.
and has fixed thereon outside the case a milled button whilst in order to afford a
bearing for the inner ends of the shafts 11 the shaft is formed tubular and
the other shaft bis prolonged to enter such tube and take a bearing therein.
In this example, a separate index number is marked upon the rear of each
plate c. and the screen e. is provided with two corresponding apertures e² whilst the
window a and mirror e³ for convenience of drawing are dispensed with, although
it is evident that they might be employed if desired.
It will be understood that in all cases a glass window of sufficient area is
provided in a suitable part of the box or case in order to admit sufficient light to
properly display the object printing.
Although it is preferred to mount the endless band of lenses upon rollers it will
be obvious that they might be otherwise mounted so as to attain substantially the
same result.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that I
claim is :-
1. A sight-testing apparatus, comprising a case or box provided with eye-
pieces, an endless belt of lenses of different powers spaced to correspond with
the eye-pieces arranged within the box or case and mounted upon angular
supporting rollers, a test object located within the box or case and means for
traversing the endless helt so as to bring each set of lenses in succession into
alignment with the eye-pieces, substantially us herein shown and described.
2. A sight-testing apparatus, comprising a case or box provided with eye-
pieces, an endless belt of lenses arranged within the box and mounted on
suitable carriers adapted to be traversed in order to bring each set of lenses
in succession into alignment with the eye-pieces, a screen located towards the
rear of the box and within the endless belt, a printed or other test object upon
the screen, an index number or the like upon the rear side of each lens carrier
corresponding with the lenses then in alignment with the eye-pieces and an
aperture in the object screen through which the index number may be viewed,
substantially as herein shown and described.
3. A sight-testing apparatus, comprising a case or box provided with eye-pieces,
an endless belt of lenses arranged within the box and adapted to be traversed in
order to bring each set of lenses in succession into alignment with the eye-pieces, a
window in the box or case and a mirror located within the box or case in the line
of sight and arranged at a suitable angle to reflect external objects, substantially
as herein shown and described.
4. A sight-testing apparatus, comprising a case or box provided with a pair of
eye-pieces, two endless belts of lenses of different powers spaced to correspond with

page_text: the eye-pieces arranged within the box or case, each endless belt being independently
mounted upon a separate set of angular supporting rollers, a test object within the
box or case and independent means for traversing each endless belt so that each
lens of each belt in succession will be brought into alignment with its respective
eye-piece, substantially as herein shown and described.
Dated this 6th day of July 1896.
VAUGHAN & SON,
Agents for the Applicant.