Year: 1892

page_text: Date of Application, 6th Sept., 1892-Accepted, 19th Nov., 1892°
Figure 3 a section of the improved apparatus.
Figure 4 is a modification of the dioptrical eye represented in the other figures.
Figures 5, 6 and 7 show details of construction of the iris arranged for variable
expansion.
I make the dioptrical eye substantially of two principal parts A and B. The
part A is open at the rear where it is provided interiorly with a cylinder a of
about 3 centimetres in length, which serves as a guide for the part B when the
latter enters the part A. with the object of lengthening or shortening the sphere.
The part A carries in front the cornea behind this the iris c and further inwards
the lens d. In the arrangement represented in Figure 4 the iris is fixed, whilst in
the arrangement represented in the other figures it is movable with variable
expansion from the minimum to the maximum of the human eye. This iris is
formed of a certain number of sectors & secured on the one hand to a fixed ring p
and on the other hand to a movable ring p'adapted to slide upon the first. Figures 5
and 6 show two different expansions; Figure 7 shows a detail of the sectors s.
The rear part B forms the continuation of the front part A. At the centre of
the rear part is placed a ground glass m on which the images are formed; the rest
terminates in a cylinder n of about 2.5 centimetres, which slides in the cylinder a
of the part A.
By means of the knob the rack shifts the lens d rearwards. The rack
through the medium of the knob g causes the rear part B to move to the front and
to the rear into and out of the front part A, thus augmenting or diminishing the
diameter from the front to the rear of the sphere. The two racks have a numbered
graduation. But in the arrangement represented in Figure 4 the rack is placed
in the interior at the upper part and the knob carries a hand which follows the
divisions of a dial.
In the two arrangements the knob is provided with a hook to which is
attached an elastic cord suspended with a small ring for showing the astheny of

page_text: In front of the sphere is a support for the correctory lens. The sphere is
fixed by a hinge upon a support C of metal or wood and can be raised or lowered,
being held in its position with the aid of the pressing screw 7.
The dioptrical eye has a didactic object, being devised for the objective and
experimental teaching of ocular dioptrics. It may also serve for fresh studies,
such as for destroying certain actual theories.
The dioptrical eye reproduces the phenomena of static refraction and dynamic
refraction, physiological as well as pathological. Physiological dynamics repro-
duces the whole extent of the accommodation from the farthest point to the nearest
point of distinct vision. Pathological dynamics reproduces all the defects or vices
of refraction from simple far-sightedness to astheny of accommodation hyper-
metropia, short sightedness and astigmatism. For this purpose a series of positive
negative, cylindrical and prismatic lenses are joined to the dioptrical eye.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed as communicated to me by my
foreign correspondent, I declare that what I claim is :-
An apparatus for use in the objective and experimental teaching of ocular
dioptrics, constructed upon the anatomical bases of the human eye and made of
two parts, one of which is fixed and carries in front a support for correctory lenses,
and the cornea, the iris and a lens in the interior, whilst the other placed at the
rear is movable with the aid of a rack and carries a ground glass where the images
are formed, the lens placed in the interior being adapted to be shifted to the front
and to the rear by means of a rack and a knob provided with a hook to which may
be attached an elastic cord with the object of showing the astheny of the
accommodatory muscle.
Dated this cal
1
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.