An Improved System and Apparatus for Uncovering and Obscuring a Photographic Lens.
Year: 1889

page_text: Date of Application, 30th July, 1889
Complete Specification Left, 5th Apr., 1890-Accepted, 14th June, 1890
PROVISIONAL SPECIFICATION.
An Improved System and Apparatus for Uncovering and Obscuring
a Photographic Lens.
I, GAÉTAU JOSEPH FORTUNE MARIE MATTIOLI, of 7 Rue de Lourcine, Paris, France,
Manufacturer of Optical Instruments, do hereby declare the nature of this invention
to be as follows:-
My invention relates to a new system and apparatus for uncovering and obscuring
a photographic lens characterised by a special mode of operation and as an example
by a novel method of construction very simple and efficient in form.
The mode of action of my system is distinguished from the obscuring plates
commonly in use by effecting the uncovering by opening gradually from the axis of
the lens or diaphragm instead of as is usual the uncovering and obscuring commencing
from the periphery. As a beneficial consequence, I obtain an increase of clearness in
the image, since all the rays of light commence and continue to pass through the axis
of the lens until the last moment of obscuration.
My apparatus is arranged to act equally well in ordinary photography as for
instantaneous photography, there being a succession of actions from " covered,"
uncovered," to again "closed." The rapidity also of these successive actions which
are effected automatically by a spring is regulated by a brake.
As an example of a practicable form of my apparatus to carry my system into
effect, I employ three fan shaped arms, mounted to pivot upon three pins carried on a
central fixed plate or disc in the camera box. These arms are pierced each with a
circular orifice, presented towards the centre of the box, the pivots on which the arms
turn being equally distributed at 120 degrees around the circle.
When the three fan shaped arms are presented, radially towards the centre of the
box, their relative circular orifices exactly coincide and offer a complete circular
orifice for the passage of the light through the lens. To carry out my system of
uncovering the lens from the centre, the said fan shaped arms are thrown over to the
first extreme position towards the periphery of the camera box, the circular orifice in
each being obscured by the solid part of the other arms so as to obscure the lens.
When the fan arms are brought to their radial position towards the axis of the lens,
the opening first commences at the axis of the lens, and becomes complete when the fan
arms are respectively, radial towards the centre, the obscuration then continuing.
as the fan arms are brought over to their opposite extreme angle towards the
periphery.
The said fan arms are automatically operated above their pivots by the tail of each
arm having an elongated hole fitted loosely over three studs upon a free annular
disc, surrounding the central plate carrying the fixed pivots of the said fan arms.
This external annular disc is attached to one end of a spiral spring of which the other
end is fixed to the camera box, the annular disc being thus caused to rotate by the
tension of the said spring when freed from the detention of a spring-pressed pawl
engaging in certain ratchet teeth on the periphery of the said rotating disc.
When the disc is set in the first position of obscuration, the ratchet pawl,
retaining it in position against the spring tension the pawl may be released in any
convenient manner, such as by the movement of a diaphragm or valve in an air pipe
used by the photographer.
The release from obscuration being effected through the air pipe by the operator,
the fan arms will come to complete uncovering of the lens, and will there be again
held by the said ratchet pawl for the required period of exposure, and thereafter will
again be released by the operator to come again to obscuration.
By continued action through the air pipe instantaneous obscuration may be effected

page_text: at a speed determined by a brake on the rotating plate controlled by set screw-
pressure, adjusted to any required amount by a scale or indicator pointer.
In order to place the apparatus against the reaction of the spring into the first
position of obscuration, ready to be released by the photographer through the air
tube, a button upon the rotating spring disc is brought through a radial slot to the
outside of the instrument.
It will be obvious, that though I describe the automatic action of the opening and
closing of the fan arms by means of a disc operating their extremities, under the
action of a spring, I may use any alternative mechanical mechanism for operating the
said fan arms to uncover and obscure according to my system for causing the un-
covering to take place from the centre of the lens, and the obscuring to terminate at
the centre, with departing from the essence of iny invention.
1001
T1 1000
FELL & WILDING,
1, Queen Victoria Street, E.C., Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved System and Apparatus for Uncovering and Obscuring
a Photographic Lens.
1 GAETAU JOSEPH FORTUNE MARIE MATTIOLI, of Rue de Lourcine, Paris in the
Republic of France, Optician, 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 :-
This invention relates to a photographic shutter which is characterized by its mode
of operation and by its construction whereby the device is rendered very simple and
practical.
As regards its operation the said device is distinguished from the shutters
heretofore employed by being gradually opened outwards from the axis of the lens
This ensures greater
or diaphragm instead of commencing at the periphery.
clearness of the image or picture, as all the rays pass through the centre of the
lens.
The improved shutter is arranged for use in ordinary photography and also in
instantaneous photography. Its rapidity of action is regulated by means of a
brake.
In order to render ny said invention better understood I have represented the
apparatus in the accompanying drawings but by way of example only.
Figure 1 represents the interior of the box or case A of the shutter in which is
shown the unlocking pawl o moved by the piston of the air tube 6 and upon which
bears the spring c.
The bottom of the box or case a carries a ring d (Figure 6) forming a short
projection, upon the periphery of which the spring disc e (Figure 3) turns.
Figuro 2 shows the outside of the box or case A which is used only as a shutter
case. The characteristic feature of my system consists in the application of the
metal plates (Figure 7) three of which are used in the model represented.
The plates or arms are each provided with a circular orifice, these orifices being
so arranged and combined as to completely cover the diaphragm when the shutter is
when
closed as shown in Figure 8 and to entirely uncover it as shown in Figure
the said shutter is open and finally to cover it again as shown in Figure 10. To
accomplish this the mechanism is mounted in the following manner.
The disc e carries a spring g one extremity of which is fixed to the box or case A
and the other to the said dise which also receives the fastening screws for the tail
piece of the three plates or arms f. Each of these screws extends through an
elongated hole i formed in the tail-piece of the arm f which allows the latter to
oscillate round a fixed point k on the guide-ring d.
To set the apparatus, the disce is provided with a knob / projecting through the
circular slot m in the box or case A (Figure 2). This disc also carries three teeth 7

page_text: (Figure 3) corresponding to the three positions of the arms f, and with which engages
a pawl o the extremity of which bears upon the piston p of an air tube. The disc
is mounted so as to oppose the action of the spring g for the purpose of setting it
and retaining it on the third tooth by the pawl o. Thus by pressing on the air bag
of the air-tube the pawl o is disengaged from the tooth of the disc e and the spring g
then acts to move the shutter suddenly to its open position.
In order to focus and to make use of my shutter in ordinary photography it will
be sufficient to place the disc e in the intermediate position (Figure 9) so as to effect
the closing after the desired time of exposure.
I have described the operation of the arm-shutters as being effected by means of
a disc, but it will be understood that this movement can be obtained by any other
mechanical means, such as sectors, rods, levers or the like without departing from the
principle of my invention.
In order to regulate the rapidity of the closing of my apparatus I have arranged
a brake upon the disc e for retarding more or less the rate of the movement of the
shutter.
The
This brake is formed by providing two pieces of greasy leather between which the
disc e is placed as shown more especially in Figure 12. One of these pieces of
leather is retained upon the surface of the disc e by a piece of saddle-back
(Figures 11 and 12) secured upon the side of the box or case A. The section of
this piece is such that the initial regulation of the pressure can be effected by acting
only upon one of the three screws which serve for fixing it to the box or case.
outer lid or cover of the box carries a scrow provided with an index; the
extremity of this screw which corresponds to the piece r, but is on the other side of
the disc e also carries a piece of greasy leather so that when the screws is turned the
disc is pressed more or less between the said two pieces of leather and consequently
its action will be more or less retarded.
I have mounted the lid or cover of the box or case A by means of screws
(Figure 13) the head of which is inside, so that they will be placed flush with the
edges of the box or case. The screw has at its extremity a slit which enables it to be
screwed home from the outside. This mode of mounting has for its object to obviate
the unauthorized opening of the box or case.
In the apparatus which I have represented the daphragms are arranged upon a
disc T adapted to turn in the interior of the box or case upon its centre u so that the
said diaphragm can be moved over the orifice of the lens. A spring pawl u¹ entering
a notch or the like retains the diaphragm in such a manner that the centre of the
latter corresponds to that of the orifice I may however observe that I do not wish to
limit myself to this arrangement.
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 :-
First. A photographic shutter comprising a device enabling the opening of the
said shutter to commence from the centre of the lens, use being made of articulated
plates provided with holes.
Second. A photographic shutter comprising arms or plates provided with holes
and articulated upon a ring d, these plates having tail-pieces articulated by means of
screws upon a rotary disc e.
Third. A photographic shutter comprising a rotary disc e which carries the pivots
for the plates and is adapted to turn upon a ring d which carries the fixed
articulations of the said plates so that when the disc e is caused to turn the plates f
cross each other and in the same moment present their openings at the centre of the
objective.
Fourth. A photographic shutter comprising a disc e provided with a spring g,
teeth n upon which acts a pawl o, a knob 1 for setting the apparatus from the outside
by turning the disc e.

page_text: Fifth. A photographic shutter comprising a brake for retarding the opening and
closing movements composed of two pieces of greased leather, one of which is fixed
whilst the other can be pressed at will from the outside by means of a screw s
provided with an index.
Dated this 5th day of April 1890
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.