Improvements in or relating to Eye-covers or Spectacles, specially suitable for the Use of Marksmen.
Year: 1896

page_text: Date of Application, 21st May, 1896
Complete Specification Left, 3rd Dec., 1896-Accepted, 16th Jan., 1897
Improvements in or relating to Eye-covers or Spectacles, specially
suitable for the Use of Marksmen.
JOHN BRIDGES LEE M.A. Barrister-at-Law. of the Inner Temple present
address, Constitutional Club Northumberland Avenue London do hereby declare
the nature of this invention to be as follows:-
This invention relates to improvements in or relating to eye-covers or spectacles
specially, suitable for the use of marksmen.
The chief aim and object of the invention is to promote sharpness or distinctness
of vision along a definite line of sight.
I attain this aim and object by means of a combination of one or more iris
diaphragms of very light weight with one or more small discs or lenses of yellow
glass with or without very small spectacle lenses of pebble or glass. This combination
I mount in a light framework and support it in front of the eye as goggles or
spectacles are supported.
The iris diaphragm serves to protect the eye from all or nearly all extraneous
light except such as can pass through the central aperture and it also serves to
regulate the quantity of light which can enter the eye from the direction of the
object looked at. The yellow glass promotes sharpness of vision especially of
distant objects by intercepting blue rays of light reflected from atmospheric haze
or mist.
The iris diaphragm especially on the concave side towards the eye exposes only
dull non-reflecting surfaces and the size of the aperture is capable of being easily
adjusted by hand while in position in front of the eye.
Ordinarily I employ one iris diaphragm only in front of each eye and one small
disc of yellow glass over the outside of the aperture. This glass disc may be
of very small diameter and thickness and therefore of very little weight. The
diameter of the disc need be only sufficient to cover the aperture of the iris
diaphragm when open to its fullest extent. To admit of the glass discs being
kept bright and clean without risk of injury to the diaphragms I employ simple
mechanical devices to admit of the glass discs being easily removed and replaced
at will.
For the use of persons whose vision is normal it is sufficient to employ a yellow
glass only with plane faces but for persons who ordinarily use spectacles very
small spectacle lenses of appropriate curvature may be employed in front of the
yellow glass or the yellow glass may be itself ground as a spectacle lens.
In mentioning yellow glass I do not wish to limit myself to the use of yellow
glass only.
Other transparent substances which absorb the most refrangible rays of the
visible spectrum may be used iustead such as slices of certain crystals or even trans-
parent structureless films.
The essence of my invention consists in the combination of a light iris diaphragm
an optical screen to cut off blue rays of light and a suitable framework to support
these in place immediately in frout of the eye and this combination may be combined
with small spectacle lenses of any desired curvature.
Dated this 21st day of May 1896.

page_text: COMPLETE SPECIFICATION.
Improvements in or relating to Eye-covers or Spectacles, specially
suitable for the Use of Marksmen.
JOHN BRIDGES LEE M.A. Barrister-at-Law of the Inner, Temple, present
address 4 Harcourt Buildings Temple London E.Cdo 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:-
This invention relates to improvements in or relating to eye-covers or spectacles
specially suitable for the use of marksmen.
The chief aim and object of the invention is to promote sharpness or distinctness
of vision along a definite line of sight.
I attain this object by mounting a small iris diaphragm on a suitable framework
so that it can be brought into any required position in front of the eye and the size
of the aperture can be adjusted by hand while the diaphragm is in place in front
of the eye. I fit over the diaphragm a cap which carries a disc of yellow glass and
may be made to carry a spectacle lens also if desired. For some years past many
riflemen have been in the habit of using under the name of orthoptics various
patterns of mounted opaque discs with small circular perforations which have served
as aperture sights immediately in front of the eye. Hitherto all orthoptics in use
have had this disadvantage in common that the sizes of the apertures in use were
unchangeable while the orthoptic was in place in front of the eye and there have
been no ready means for determining by comparison and trial which particular size
of. aperture would be most suitable at the particular time and place and to the
particular individual. Also it has been matter of common complaint that air
blowing through the open holes has hurt the eyes. The mounted iris diaphragm
which I use is completely under the control of the marksman who can easily and
without trouble ascertain by comparison and trial the exact size of aperture
which suits him best at the time. The cap with its contained glass effectually
protects the eye from any draughts through the aperture.
The yellow glass will be found to help the marksman to see more clearly
through haze or mist and if a spectacle lens has to be used it will be found of great
advantage to have it in the cap where it will always occupy the same relative
position as regards the aperture.
"
In order that my invention may be more clearly understood and readily carried
into effect I will proceed with the aid of the accompanying drawings more fully to
describe the same.
Fig. 1 is a front view. Fig. 2 is a side view and Fig. 3 is an enlarged view of
the right hand portions of Figures One and Two the cap and structures which it
carries being shewn.in section.
a is an ordinary spectacle frame of steel or other suitable material with a straight
bridge. b is a covering of soft velvet over that part of the bridge which presses
against the nose. c is the attachment of a band of elastic which passes round the
head and helps to hold, the spectacle frame in position. d'is ordinarily a disc of
neutral tint glass with parallel faces but it may be glass of any other suitable tint
or a spectacle lens of any desired curvature. e is a disc of vulcanite or ebonite or
other suitable opaque material, this disc can be revolved by hand in its own plane
within its frame and it is perforated eccentrically by one fairly large aperture.
f is a small iris diaphragm which is operated by a projecting milled head f..
The aperture of the iris diaphragm is concentric with the aperture in the
vulcanite disc and the base of the frame which.contains the iris diaphragm is rigidly
fastened in position by screws g which traverse a métal ring hand the vulcanite and

page_text: penetrate the metal frame of the iris diaphragm and hold it fast without interfering
with the mechanism for opening and closing the iris diaphragm. i is a metal cap
with a milled head. This cap slips over the milled head of the iris diaphragm. It
is provided with small spring catches which serve to prevent the cap from being too
easily pulled off and safeguard it from all risk of falling off accidentally. One of
these catches is shewn at j. The cap is also provided internally with one or more
projecting pins which fit corresponding notches in the milled head of the iris
diaphragm. These pins and notches are not shewn in the figures. Their use is to
secure that whenever the cap is revolved it must carry with it the milled head of
the iris diaphragm and thus enlarge or diminish the aperture as desired. k is a
circular disc of optically worked bright yellow glass. Ordinarily this glass will have
parallel faces but it may be ground to the form of a spectacle lens when desired or
an ordinary spectacle lens may be carried in the same cap either in front of or
behind the yellow glass disc or occasionally instead of it. is an open ring of
stiff elastic metal wire which serves to hold the yellow disc or spectacle lens in
place in the cap. This ring can be easily taken out and replaced so that the glasses
can be easily removed and replaced.
The construction and arrangement of parts herein described are such as I have
found to answer in carrying my invention into effect but various modifications of
detail may be adopted without departing from the peculiar character of my
invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. The complete combination of parts substantially as herein shewn and
described.
2. The combination of an iris diaphragm and an opaque disc of vulcanite or other
suitable material substantially as herein shewn and described and for the purpose
stated.
3. The combination of an iris diaphragm and a disc of yellow glass carried in a
cap which slips over the iris diaphragm substantially as herein shewn and described
and for the purpose stated.
4. The combination of an iris diaphragm and a spectacle lens mounted in a cap
either with or without the yellow glass disc substantially as herein shewn and
described and for the purpose stated.
5. The combination of an iris diaphragm and spectacle lens with or without
colored glass the combination being intended to be supported immediately in front
of the eye to promote sharpness of vision.
Deted thi 31