Macrolens assembly having a distance adjustment of more than 360 degrees

A macrolens assembly which has two distance setting rings which are coaxially arranged and are fitted into each other and each of which has on its radial exterior a distance scale. A control window is provided in the lens mount and in the outermost distance setting ring directly abutting there against in radial direction. The inner distance setting ring which can be rotated manually by means of a driving ring can be coupled to the outer distance setting ring by a driver formed as a ball catch. In this way, after one rotation of the driving ring, first the scale on the outer distance setting ring, when the scale on the inner distance setting, becomes visible.

BACKGROUND OF THE INVENTION 
The invention relates to a macrolens assembly with a lens mount including a 
lens system, and in which is rotatively supported a distance setting ring 
with a scale mounted coaxially to the lens axis. 
In macrolenses it has been conventional to set the focus distance using a 
distance setting ring. Because it is necessary to design the distance 
setting ring in such a way that it can be rotated more than 360.degree. , 
it is a common practice to make the distance scale in different colors 
placed opposite to a multicolored index mark. This creates the problem 
that the colors must be assigned correctly when setting the distance 
setting ring. Faulty focusing becomes possible especially when trying to 
quickly set the lens with relatively little concentration. This also 
provides difficulty under poor light conditions, because of the reduced 
color perception of the human eye. 
In recognition of this problem, the present invention has as its object the 
provision of a macrolens with which with relatively little increased 
technical effort the distances can be set with precision throughout the 
entire range. 
According to the invention, this object is achieved by providing at least 
two distance setting rings arranged inside the mount and fitted into each 
other. Only the radially innermost distance setting ring is guided from 
exteriorly of the mount, through an annular opening therein, to form a 
driving ring. The distance setting rings adjacent to the innermost 
distance setting ring are rotatively connected to the innermost distance 
ring by means of a driver that can be automatically released by a radial 
pressure. Both the lens mount and the distance setting rings adjacent to 
the radially innermost distance setting ring are each provided with a 
control window. Transition and easy changing from one distance setting 
ring to the next is possible with this solution, which uses a relatively 
simple design. In this way, only one distance measurement is ever visible 
from the control window, this distance being always advantageously 
assigned to the index mark. Thus faulty settings are harder to make, even 
if the distance setting ring is activated hastily and with little 
concentration. 
Another advantage is that a more practical gradation of colors of the 
distance range becomes now possible. For example, the distance setting 
rings in the range from infinite to one meter may be colored blue, green 
in the adjoining range, and red in the very special macrorange. This makes 
very fast spotting of the desired distance range possible, followed by an 
accurate focusing. 
An advantageous modification of the invention consists in providing one 
stop each on the radially innermost distance ring, on its radial exterior 
and on the interior of the mount, which stops are staggered towards each 
other in a tangential direction at a distance corresponding to the 
tangential width of the control windows, whereby the driver connected to 
the second distance setting ring is provided between these two stops. The 
start of the distance scale on the radially outer ring is provided with 
this construction. The latter is carried along by the driver from the 
radially inner distance setting ring, which can be rotated by the driving 
ring provided on the exterior mounts. After a 360.degree. rotation minus 
the tangential width of the control window there appears in the radially 
outer distance ring another control window, so that the scale on the 
radially inner distance ring now becomes visible. The radially outer 
distance ring is held in position by the stop of the driver on the stop 
connected to the interior of the mount, and the distance scale continues 
smoothly on the inner distance ring. 
According to the invention, the control windows in another preferred 
embodiment of the invention are staggered one directly behind the other in 
the direction of the radial exterior of the distance rings for the 
installation of the scale. 
According to another advantageous variant of the invention, provision is 
made for the construction of the driver as a ball catch, which acts 
bilaterally in the radial direction and which, in the initial position of 
rotation determined by the contact of the two stops with the driver, locks 
into a first notch of the radially innermost distance ring, and into 
another notch provided on the interior of the mount is staggered in 
relation to the first notch at a tangential distance corresponding to the 
width of the control windows. In this way, the initial position of the 
driving ring is fixed by a non-passable stop. Thus, the activation of the 
driving ring for distance setting is possible in only one direction, 
whereby the stop of the radially inner distance ring is moved away from 
the stop of the lens mount. By appropriately spacing the two notches from 
each other, it is ensured that, after one rotation, the control window of 
the radially outer distance ring is located exactly beneath the control 
window arranged in the lens mount. 
According to another embodiment of the invention, the driver may 
advantageously be formed as a permanent magnet, which, together with its 
pole pieces, is connected to the distance ring adjacent to the mount and 
cooperates with air guides from ferromagnetic material, which are mounted 
on the stops connected to the interior of the mount, or to the radially 
innermost distance ring. Such a notch-free driver is relatively simple to 
make and is practically trouble-free. 
Finally, another advantageous embodiment of the invention is obtained by 
providing three distance rings, each of which is rotatively connected by 
means of drivers to the radially innermost distance ring. Such a 
structural approach makes an extremely high scale resolution possible, so 
that a highly accurate distance setting can be carried out.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
The macrolens assembly 1 depicted in FIG. 1 includes a mount 3 containing a 
lens system 2 which is not shown in detail and has a control window 4. 
Directly beneath the mount 3, a radially outer distance setting ring 5 is 
provided with a driver 7 that is formed as a ball catch 6 rigidly coupled 
thereto. Another distance setting ring is provided inside this distance 
setting ring 5, having a control window 8 and a distance scale on its 
radial exterior. This radially inner distance setting ring 9 can be 
rotated manually by means of a driving ring 10. 
As can particularly be seen from FIGS. 2 to 7, the two distance setting 
rings 5 and 9 are arranged coaxially to the lens axis 11. The lens mount 3 
has interior faces defining a stop 12 and a concave notch 13. The radially 
inner distance setting ring 9 has an exterior face defining a stop 14 as 
well as concave notch 15. FIG. 2 shows the initial position of rotation in 
which the two stops 12 and 14 each abut against driver 7. In this initial 
position of rotation, the inner distance setting ring 9 can rotate by 
means of driving ring 10 only in the direction indicated by arrow 16. 
Distance setting is effected from the position in FIG. 2 by rotating the 
driving ring 10, and thereby the radially inner distance setting ring 9, 
in the direction of arrow 16. The ball catch is rigidly coupled to outer 
distance setting ring 5, to move along therewith. Ball catch 6 is 
initially connected into notch 15 and is carried along together with the 
radially outer distance setting ring 5. As can particularly be seen in 
FIG. 3, the distance scale 17 mounted on the radial exterior of the outer 
distance setting ring 5 appears in the control window 4 of lens mount 3. 
After one rotation of slightly less than 360.degree. , the radially outer 
ball catch 6 locks into notch 13 of mount 3 and, at the same time, also 
abuts against stop 12 of mount 3 as shown in FIG. 4. In this position, as 
shown in FIG. 5, control window 8 of outer distance setting ring 5 is 
placed in coincidence beneath control window 4 of mount 3. Distance scale 
18 on the radial exterior of inner distance setting ring 9 becomes visible 
in this configuration. Since inner ring 5 is locked into position, the 
scale 18 remains visible. 
If distance setting ring 9 is further rotated in the direction of arrow 16, 
the radially inner ball catch 6 of driver 7 disengages from notch 15, 
thereby allowing only inner distance setting ring 9 to move. FIG. 6 
depicts the final position of rotation in which the end of scale 18 is 
reached and stop 14 of inner distance setting ring 9 abuts against 
structure 7, which also abuts against stop 12 of mount 3. 
If driving ring 10 is now rotated back in the direction indicated by arrow 
19 (FIG. 6); which is opposite to the direction of rotation discussed 
above, driver 7 and therefore the radially outer distance setting ring 5 
remains locked into notch 13 of mount 3 by means of the radially outer 
ball catch, and thus remains fixed therein until notch 15 of inner 
distance setting ring 9 locks into ball catch 6 and thereby carries outer 
distance setting ring 5 along therewith. 
The embodiment shown in FIGS. 8 to 11 includes another distance setting 
ring 25 located between the radially outer distance setting ring 5 and the 
radially inner distance setting ring 9. The radially inner distance 
setting ring 9 is rotated manually by means of a driving ring (not shown), 
in the direction of arrow 27. FIG. 8 shows inner ring 9 being rotatively 
connected by means of drivers 7 and 26, respectively to the radially outer 
and inner distance setting rings 5 and 25, so that these rings will also 
rotate in the direction of arrow 27. The distance scale of outer-most 
distance setting ring 5 appears first in control window 4 of the mount. At 
the time when driver 7 abuts against the stop 12 of mount 3, control 
window 8 becomes in coincidence beneath control window 4, so that the 
distance scale on the second distance setting ring 25 becomes visible. 
This second distance setting ring 25 also has a control window 28, which 
becomes in coincidence beneath the two control windows 4 and 8 after one 
rotation when driver 26 is abutting against driver 7 which already abuts 
stop 12 (FIG. 10). The distance scale mounted on the innermost distance 
setting ring 9 becomes visible at this point. 
As apparent from FIG. 12, ferromagnetic air guide 33, 34 are connected to 
stop 12 and stop 14, respectively. The driver 7 which is connected to the 
radially outer distance setting ring 5 is formed as a permanent magnet 30, 
which, as seen in FIG. 13, may be provided with pole pieces 31, 32. This 
magnet forms a magnetic circuit with the air guides and brings about the 
entrainment of the pieces. 
Although only a few embodiments have been discussed in detail above, those 
having ordinary skill will certainly understand that many modifications 
are possible. Such modifications are intended to be encompassed within the 
following claims.