Improvements in and relating to Telescopes, Microscopes, and · Photographic Objectives..
Year: 1895

page_text: Date of Application, 28th Feb., 1895-Accepted, 11th Jan., 1896
COMPLETE SPECIFICATION,
Improvements in and relating to Telescopes, Microscopes, and ·
Photographic Objectives..
I, ALFRED CONRAD BIESE, of 32, Maassenstrasse, Berlin, in the Empire, of
Germany, 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 :—
Generally, every optical instrument consists of a number of systems of lenses.
which act upon each other in such a manner as to produce an image which may be
either real or imaginary. It may be of great interest to cause this image to vary
as regards its dimensions, which can always be done by moving the systems of
lenses relatively to each other. But of still greater importance is the capability of
causing this successively magnified image to appear always at one place which may
either be a fixed point in the instrument, or always be at a constant distance from.
a movable part of the instrument.
Irrespective of the number of separate systems of which the total or whole
system may be composed, it will always be possible to produce this result by means.
of two movements:-a linear movement and a movement in accordance with the
innate law of optics, under the assumption that the separate systems share this
movement.
The accompanying drawings illustrate by way of example_an_operating
mechanism for effecting this purpose and which is hereinafter described in its
application to a single and to a double telescope, in which a system of concavÓ
lenses or of convex lenses is inserted between the eye-piece and the objective.
In the accompanying drawings,
Figure 1 Sheet No. 1 is a view in section of a terrestrial telescope with continual'
magnifying action, and
· Figure 2 Sheet No. 1 is a view-partly in section-of a double or binocular
telescope, and
Figure 3 Sheet No. 2 is an enlarged detail view in perspective partly in section.
For the purpose of producing in the single telescope shown by Figure 1, the
aforementioned constant distance of the plane of the image from the eye-piece, the
objective tube a has a head in which a milled nut C moves. This nut serves to.
move the eye-piece tube a-which is provided with a worm or screw-thread→
uniformly in or out. The milled nut C has further connected to it a tubular-
piece in the outer surface of which is cut a curved groove & the threads or
spirals of which are in accordance with the optical laws of the systems of lenses.
employed. Into this groove there engages a sorew g which is guided in a reotilinear
manner in a slot in the objective tube a, and is fixed to the tubular part_b.
carrying the lens-system that produces the variable effect. Generally the spirals
of this groove are hyperbolical curves. The tube 6 will consequently-when
the milled nut C is uniformly rotated-move with increasing or decreasing
velocity, according to the direction of the movement, whilst the eye-piece will
travel with uniform velocity. The combination of these two movements with
each other causes the plane of the image also to move with a uniform velocity,.
so that the said plane will always be at the same distance from the eyepiece, and
will therefore always appear sharply defined to the eye of the observer.
.
The above described arrangement may be applied with unimportant alterations
to all kinds of optical instruments wherein an objective is used consisting of several
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page_text: sets of lenses with variable focus, that is to say Galilean and astronomic telescopes
and photographic objectives of long range. The way in which the lenses contained
in the objective tube are moved is not an essential matter.
The construction of a double or binocular telescope as represented in Figure 2
differs from that mentioned above, in that the mechanism for producing the
requisite movements is not placed within each individual tube but between both
the tubes. For this purpose a tube is movably affixed to the bridge i which
connects both these tubes, this tube k carries a milled nut gearing with its worm
into a worm made on the outside of a smaller tube n placed within the first one.
The milled nut also carries a steel tube m in which is formed the curved groove d
shaped according to the curve found by calculation for this purpose. The steel
tube m is surrounded by a tube o which is joined by way of the bridge p to that
part of the apparatus which carries the correcting lenses and the eye-piece tube
is moved by means of the tube n. The tubes, n, m and o are surrounded by a
casing 9 wherein a slot is made which guides in a rectilinear manner a screw
fastened to the tube o and gearing with the curved groove d of the steel tube m.
I wish it to be particularly understood that I do not limit myself to the precise
details of construction hereinbefore described and illustrated by the accompanying
drawings, but that I hold myself at liberty to make such changes and alterations
as fairly fall within the spirit and scope 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 improvements in telescopes and the like, substantially as hereinbefore
described and illustrated by the accompanying drawing.
(2.) An actuating mechanism for moving simultaneously two optical systems,
consisting essentially of a groove such as d cut in a rotating cylinder such as c and
having spirals which are cut in accordance with the optical laws of the systems
acting upon one another which are generally of hyperbolical form, the said grooved
serving to guide a stud such as g which is fixed to the part boarrying the second
system a, and is rectilinearly guided in another part of the instrument, so that
the rotation of the cylinder e simultaneously imparts to the second system ba
linear movement relative to the hyperbolical movement for the purpose of variably
magnifying the image projected by the whole system while keeping said image at
a definite spot which is either fixed in the system itself, or has always the same
distance from a definite part of the instrument, as set forth.
(3.) The arrangement of carrying out the mechanism specified in the preceding
claim as applied to a telescope, characterized by the simultaneous motion of the
eye-piece by means of a worm and a milled nut, and of the tube carrying the
concave lens by means of a screw moving in a slot in the objective tube and also
in a curved groove d in the tubular part connected to the milled nut, as set forth..
(4.) In the operating mechanism as specified in the preceding claim, a modifi-
cation consisting essentially, when applied to double telescopes, of a separate
special tube connected to the middle bridges or saddle pins of the separate
telescope tubes, as set forth;
: .
Dated this 28th day of February 1895.