Improvements in Eye Glasses.
Year: 1899

page_text: Date of Application, 22nd Mar., 1899-Accepted, 29th Apr., 1899
Improvements in Eye Glasses.
I, Dr. WILHELM SCHULEK, of 23, Sasu, Budapest, in the Kingdom of Hungary,
and Empire of Austria, University Professor and Nominated Royal Hungarian
Ministerial Councillor, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
-
It has long been suggested to use eyeglasses similar in their external appearance
to those heretofore in common use but having two or more glasses arranged to
leave a space or spaces between them for the reception of a liquid or gas possessing
certain particular qualities. The filling medium was to be bisulphate of quinine,
petroleum or the like, which substances however do not give permanent results
as their nature changes greatly in time.
This kind of eyeglass never received the favour it was expected to attain from
a medical point of view the explanation being that the primitive forms of eye-glass
(in which the several glasses were cemented together) were never improved and
that in the selection of the filling material sufficient consideration was not given
to the most important point, namely the exclusion of the ultra violet light rays
which have such pernicious effects upon the eye.
This invention aims at the perfection of these kind of eyeglasses in two ways,
and is illustrated in the accompanying drawing in which,
Figures 1 and 2 shew two constructional forms of eyeglass, and
Figure 3a spectrum showing the exclusion of violet rays.
It is first intended to make a cheap and reliable form of eyeglass sufficient for
all practical purposes and also to provide means whereby the ultra violet light
rays are entirely excluded.
These means consist in the use of triphenylmethane or nitrobenzol by using
xylol or alcohol as a solvent. Obviously the concentration and the thickness of
the layer or filling must vary according to requirements. For dis-
solving triphenylmethane in xylol a proportion of 15 in 100 up to 45 in 100 is
suitable with a thickness of filling or layer 2.5 to 1.25 m/m. The use of thinner
layers than these depends upon whether it is possible to overcome the difficulties
in practice in connection therewith.
Instead of the liquid filling a filling or even a coating, of a solid substance may
in some instances be found useful, and for this purpose a mixture of nitrobenzol
and celloidin, or triphenylmethane and Canada balsam may be used.
The lenses may be flat or otherwise shaped and may be placed parallel or in any
other way to each other so as to enable these eyeglasses to be used for the purposes
of optical corrections by mounting them with one or two concave or convex lenses
as may be required.
A highly important point besides the concentration of the filling liquid is the
thickness of the layer or filling. Therefore it is necessary to take great care that
the predetermined thickness of layer is strictly carried out in constructing this
kind of eyeglass.
To enable this to be carried out the mounting or frame A, which may be of any

page_text: suitable material not influenced by the liquid, is furnished with a strong inner
frame a determining the thickness of the layer (or filling) of the liquid. This
inner frame a must therefore be made to exact size; it also forms a firm support
for the glasses B and is provided with flaps b adapted to be turned over the edges
of the glasses and so form a thoroughly reliable mount which for additional
security may be coated with a suitable cement, varnish or the like.
The mount is provided with a small opening c, passing through the frame a,
which may be closed by a fine screw or by means of varnish or by other suitable
means. With 3 glasses there will be two hollow spaces and the mount must in such
case be made with two frames a cach having a small hole c.
Good results may also be obtained with the mount shown in Figure 2. The
inner frame a in this case is of glass and is secured either by blowing, cementing or
by any other convenient means, and afterwards the exterior portion A is fixed
in the ordinary manner.
The exclusion of the effects of ultra violet light by the eyeglass constructed in
accordance with this invention is shown in Figure 3 in spectrums.
The uppermost field represents daylight in clear sky; the letters (F, G, H, K,
L, M, N, designate the well known Frauenhofer lines. The short fields show
clearly how far the exclusion of the ultra violet light rays depends upon the
concentration of the liquid marked in each case viz. (45:100, 35:100, 25:100,
15;100) and with the thickness of the layer of the liquid, (being 1.25 and
2.5 m/m).
From these spectrums it would appear that a solution of 35 parts tri-phenyl
methane in 100 parts xylol with a thickness of layer of 1.25 m/m gives the most
favourable results.
For the purposes of certain special cases other proportions of concentration
and thickness of layers may however be found more useful.
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 what
I claim is:-
1. Eyeglass characterized by a solid or liquid layer of tri-phenylmethane or
nitro-benzol used either in a dissolved state or mixed with substances which are
not acted upon.
2. A (constructional) form of eyeglass of the kind claimed in Claim 1, charac-
terized by a layer between the double lenses 13 of a solution of triphenylmethane
in xylol or of nitrobenzol in alcohol.
3. A form of eyeglass of the kind claimed in Claim 1, characterized by a layer
upon the glass 13 of a mixture of triphenylmethane and Canada balsam, or of
nitrobenzol and celloidin.
4. A form of eyeglass as claimed in Claim 1, characterized by a mount A fitted
with one or more inner frames a for determining the distance between the
lenses B, substantially as described with reference to Figures 1 and 2 of the
annexed drawing.
5. A form of eyeglass as claimed in Claims 1 and 4, characterized by a frame a
provided with flaps 6 overlapping the lenses B and with a filling or inlet hole c.
6. A form of eyeglass as claimed in Claims 1 and 5, characterized by having an
inner frame a of glass to which the lenses B are secured either by blowing or by
cementing.
Dated this 22nd day of March 1800
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.
Agents for the Applicant.