U.S. patent application number 12/797388 was filed with the patent office on 2010-12-16 for objective changer.
This patent application is currently assigned to LEICA MICROSYSTEMS CMS GMBH. Invention is credited to Manfred Gilbert, Gerhard Pfeifer.
Application Number | 20100315707 12/797388 |
Document ID | / |
Family ID | 43123054 |
Filed Date | 2010-12-16 |
United States Patent
Application |
20100315707 |
Kind Code |
A1 |
Gilbert; Manfred ; et
al. |
December 16, 2010 |
Objective Changer
Abstract
An objective changer for a microscope is described, comprising a
changing device for transferring at least a first objective held in
a first objective holder from a first stand-by position along a
first transfer path into an operating position where the first
objective defines an optical axis and a second objective held in a
second objective holder from a second stand-by position along a
second transfer path into an operating position where the second
objective defines an optical axis. The first and second transfer
paths differ from each other but both extend substantially
perpendicular to the optical axis at least within a first area of
the first transfer path and a first area of the second transfer
path.
Inventors: |
Gilbert; Manfred;
(Schoeffengrund, DE) ; Pfeifer; Gerhard; (Wetzlar,
DE) |
Correspondence
Address: |
ALEXANDER R SCHLEE;SCHLEE IP INTERNATIONAL P.C.
3770 HIGHLAND AVENUE, SUITE 203
MANHATTAN BEACH
CA
90266
US
|
Assignee: |
LEICA MICROSYSTEMS CMS GMBH
Wetzlar
DE
|
Family ID: |
43123054 |
Appl. No.: |
12/797388 |
Filed: |
June 9, 2010 |
Current U.S.
Class: |
359/381 |
Current CPC
Class: |
G02B 21/02 20130101;
G02B 21/248 20130101 |
Class at
Publication: |
359/381 |
International
Class: |
G02B 21/02 20060101
G02B021/02; G02B 21/00 20060101 G02B021/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 16, 2009 |
DE |
DE 102009026978.9 |
Sep 2, 2009 |
DE |
DE 102009029146.6 |
Claims
1. An objective changer for a microscope, comprising: a changing
device for transferring at least a first objective held in a first
objective holder from a first stand-by position along a first
transfer path into an operating position where the first objective
defines an optical axis and a second objective held in a second
objective holder from a second stand-by position along a second
transfer path into an operating position where the second objective
defines an optical axis, wherein the first and second transfer
paths differ from each other but both extend substantially
perpendicular to the optical axis at least within a first area of
the first transfer path and a first area of the second transfer
path.
2. The objective changer according to claim 1, wherein for the
first objective a first drivable slide is connected to the first
objective holder and for the second objective a second drivable
slide is connected to the second objective holder.
3. The objective changer according to claim 1, wherein the first
and the second transfer paths share within their respective first
areas one and the same plane and extend within that plane at least
one of along a straight line and a curved line.
4. The objective changer according to claim 3, wherein the first
and the second transfer paths are located next to each other and
defined a V-shape.
5. The objective changer according to claim 1, wherein the first
and the second objective holders may each hold a plurality of
objectives assuming simultaneously their respective stand-by
position.
6. The objective changer according to claim 1, wherein the first
and the second transfer paths each comprise a second area extending
directly adjacent to the first area.
7. The objective changer according to claim 1, wherein the
respective first area of the first and the second transfer paths is
a major part of the respective entire first and second transfer
paths.
8. The objective changer according to claim 6, wherein the
respective second areas of the first and the second transfer paths
comprise a component extending in a direction parallel to the
optical axis.
9. The objective changer according to claim 2, further comprising a
first adjusting unit for the first objective and a second adjusting
unit for the second objective, wherein both the first and the
second adjusting units each comprise a slide.
10. The objective changer according to claim 2, further comprising
at least one guide rod for each one of the first and second slides,
wherein the slides can be moved along the respective at least one
guide rod.
11. The objective changer according to claim 9, further comprising
at least one guide groove in each of the first and the second
adjusting unit, wherein the first and second slides are movable
along the respective guide grooves.
12. The objective changer according to claim 10, wherein the first
and the second slide are connected to a respective guide receptacle
of the respective first and second adjusting units via the at least
one guide rod.
13. The objective changer according to claim 11, wherein the guide
grooves are formed on respective stationary carriers of the
respective first and second adjusting units.
14. The objective changer according to claim 13, wherein the first
and the second slide are connected to a respective guide receptacle
of the respective first and second adjusting units and respective
couplings for coupling the first and the second slide and the
respective guide receptacle to the respective guide groove are
provided, the guide grooves being provided in a stationary
carrier.
15. The objective changer according to claim 9, further comprising
a respective drive mechanism for the first and second adjusting
units for each of the first and the second slide.
16. The objective changer according to claim 2, wherein the first
and the second objective holder are arranged pivotably on the
respective first and second slide and are connected to the
respective slide via at least one of a biasing device and a lever
mechanism holding the center axis of the respective objective
holder at least in the respective first area of the first and
second transfer path under an angle of inclination relative to the
optical axis.
17. The objective changer according to claim 16, wherein the first
and the second transfer paths each comprise a second area extending
directly adjacent to the first area and the at least one of the
biasing device and the lever mechanism hold the center axis of the
respective objective holder in the second area of the respective
transfer path under a smaller angle of inclination relative to the
optical axis than the one in the first area.
18. The objective changer according to claim 9, wherein the first
and second adjusting units are connected to respective intermediate
plates.
19. The objective changer according to claim 18, wherein on the
respective intermediate plate a centering mount for stationary
fixing of the first and the second objective holder is
arranged.
20. A microscope having an objective changer comprising: a changing
device for transferring at least a first objective held in a first
objective holder from a first stand-by position along a first
transfer path into an operating position where the first objective
defines an optical axis and a second objective held in a second
objective holder from a second stand-by position along a second
transfer path into an operating position where the second objective
defines an optical axis, wherein the first and second transfer
paths differ from each other but both extend substantially
perpendicular to the optical axis at least within a first area of
the first transfer path and a first area of the second transfer
path.
21. The microscope according to claim 20, further comprising a
first adjusting unit for the first objective and a second adjusting
unit for the second objective, and a respective first and second
support element that is adjustable in focusing direction and on
that the first and second adjusting units are mounted.
22. The microscope according to claim 20, wherein for the first
objective a first drivable slide is connected to the first
objective holder and for the second objective a second drivable
slide is connected to the second objective holder; a first
adjusting unit for the first objective and a second adjusting unit
for the second objective are provided, wherein both the first and
the second adjusting units each comprise a slide; the first and
second adjusting units are connected to respective intermediate
plates; and the respective intermediate plates can be connected to
a respective support element of the microscope, said support
element being adjustable in focusing direction.
23. The microscope according to claim 22, wherein the intermediate
plate is connected to a counter receptacle of the support element
via a dovetail connection.
24. The microscope according to claim 21, wherein on the respective
intermediate plate a centering mount for stationary fixing of the
first and the second objective holder is arranged.
25. The microscope according to claims 20, wherein the respective
first area of the first and second transfer paths extends from a
user perspective substantially in a direction to and from in
relation to a position of the user when using the microscope.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priorities of the German patent
application DE 102009026978.9 having a filing date of Jun. 16, 2009
and of the German patent application DE 102009029146.6 having a
filing date of Sep. 2, 2009. The entire content of these 2 prior
German patent applications is herewith incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to an objective changer, in
particular for a microscope, having a changing device for at least
two objectives as well as to a microscope having such an objective
changer.
[0003] Objective changers of this type are known from the prior
art. In addition to the known objective turrets, in which several
objectives are mounted on a carrier in circular arrangement and the
desired objective can be swiveled into the operating position by
rotating the carrier, objective changers are known in which
objectives can be individually brought from a stand-by position
into an operating position which is common to all objectives.
[0004] The latter type of objective changers has proved to be
advantageous in particular for applications in the field of
electrophysiology since hereby a large free space around the
objective and the object can be created. Typically, for
applications in electrophysiology a sample table having a sample
placed thereon is no longer moved after positioning of the sample.
On the one hand, this is because of the often existing touch and
vibration sensitivity of the samples to be examined and, on the
other hand, because of the fact that the examined biological
samples are often manipulated during their observation. Such
manipulations require a large free space around the object. Often,
the preparation is accessed by several manipulators at the same
time. Via the manipulators, for example current, voltage or else
dyes, liquids etc. are applied to the sample or substances are
injected into the sample. Often, the manipulators remain in their
position relative to the sample throughout the entire examination.
In addition to the demand for a large free space, it has to be
taken into account that there is a wish to be able to use several
(i.e. at least two) objectives for object examination in order to
be able, for example, to change from a general image having a low
magnification to a detailed image having a high magnification.
[0005] When changing an objective, it has to be taken into account
that the objectives used in electrophysiology mostly have a very
little working distance to the examined preparation or even dip
into the liquid often surrounding the preparation. In most cases,
the preparations are placed in dish-shaped containers, the
so-called Petri dishes. When changing an objective it has to be
guaranteed that the objective is lifted over the edge of the
container and the new objective is only lowered when it has reached
the inner area of the container. In doing so, any movement of the
sample table for facilitating the objective change is to be
avoided.
[0006] Against this background, DE 10 2007 042 260 A1 of the
applicant suggests an objective changer having a changing device
for at least two objectives in which each of the objectives can be
pendulously swung into its operating position near the focal
position via the changing device. From the operating position, the
objectives can be swung into a stand-by position. Advantageously,
the pendulous swinging motion takes place in one plane. Swinging-in
of the one objective can cause the swinging-out of the other
objective. In addition, the objectives can be lowered during
swinging-in and lifted during swinging-out. As the entire swinging
area of the objectives has to be kept free of manipulators, this
objective changer proved to be disadvantageous for some
applications.
[0007] The swinging-out of an objective from an observation
position into a stand-by position for avoiding obstructions and
intersections in the case of examinations in the field of
electrophysiology also represents the basic principle of the
teaching of JP 09258088A.
[0008] For the examination of samples in a sample chamber filled
with immersion medium, DE 10 2007 018 862 A1 suggests an objective
changing device for a microscope having two fixed objectives which
are arranged movably with respect to the sample chamber. By a
corresponding displacement, one of the two objectives can be
brought into the operating position, while the respective other one
is in the stand-by position.
[0009] EP 1 168 027 B1 suggests an objective changer by means of
which the longitudinal axis of the objective can be moved
substantially coaxially to the optical axis of the objective for an
objective change. In one embodiment, an objective can be moved
along a curved guide rail, this curve extending approximately
parabolically, the plane of the parabola including the optical axis
of the objective and the apex of the parabola corresponding to the
desired position (operating position) of the objective. In another
embodiment, the objective is lifted from its desired position by
means of a gripper arm in the direction of its optical axis and is
brought into a storage position (stand-by position) by means of a
swivel arm. In still another embodiment, a selected objective is
brought from a storage position via a feed channel extending
coaxially to the optical axis of the objective but perpendicular to
the optical axis of the microscope into its desired position,
wherein it has to be erected for this purpose from a "lying
position" into an "upright position" so that the optical axis of
the objective coincides with the one of the microscope.
[0010] Finally, from German patent specification DE 198 22 870 C2,
a device for an objective change in an up-right microscope having
at least two objectives and an associated focusing device is known,
which can move the objective located in the active position (i.e.
in the operating position) in the direction of the optical axis, as
well as having a common slide receiving the objectives in objective
holders, which slide can be moved perpendicular to the optical axis
for objective change. Here, for moving the slide one single
actuating element is provided with which in addition also the
desired objective can be lifted or lowered and be brought into the
active position. This actuating element is a rod mounted on the
slide, which rod is used as a pull rod in order to bring one of the
two objectives mounted on the slide into the operating position and
the other one into the stand-by position. When rotated, the rod
actuates a lever which interacts with an objective holder in order
to lift or lower the same. Given this solution it proves to be
disadvantageous that the two objectives are in a fixed position
relative to one another so that the free working space is highly
limited because of the second objective which is located in the
stand-by position and arranged in the direction of the user.
[0011] Against this background, it is the object of the present
invention to specify an objective changer which makes possible an
objective change that is as easy as possible while providing the
largest-possible free space around the objective located in the
operating position and the preparation to be examined.
SUMMARY OF THE INVENTION
[0012] This object is solved according to the invention by an
objective changer according to claim 1 and a corresponding
microscope according to claim 20. Advantageous embodiments result
from the respective subclaims and the following description.
[0013] The inventive objective changer having a changing device for
at least two objectives, by means of which one objective each can
be transferred from a stand-by position into an operating position,
the objective located in the operating position defining an optical
axis, is characterized in that for each objective the changing
device has a movable objective holder for transferring an objective
from a respective stand-by position assigned thereto into the
operating position along a displacement path which is different
from the one of other objectives, each displacement path being
oriented substantially perpendicular to the optical axis at least
within a first area.
DETAILED DESCRIPTION OF THE INVENTION
[0014] Here, it is useful when for each objective one drivable
slide each is provided on which an objective holder can be
mounted.
[0015] The objectives can be moved directly at their respective
objective holders either manually or by a motor. Usefully, slides
are provided which carry the objective holders and which in turn
can each be driven manually or by a motor. For reasons of
simplicity, the latter case is to be assumed in the following, i.e.
the presence of a slide on which an objective holder is arranged
which in turn can carry an objective.
[0016] With an objective changer of this type, thus each objective
is moved substantially perpendicular to the optical axis by means
of a drivable slide assigned thereto. Thus, this is not the usual
arrangement of objectives on a rotating disk, where the desired
objective is brought into the operating position by rotation of the
rotating disk. In the typical case of application of a microscope,
which is to be assumed in the following in a non-limiting manner,
the optical axis usually runs in vertical direction so that the
objectives are moved in horizontal direction in the objective
changer according to the invention. Here, it is useful to move the
objectives away from the user when the objective is brought from
the operating position into its stand-by position. Usefully, the
mentioned (first) area of the displacement path constitutes the
main part of the entire displacement path of an objective from its
stand-by position into the operating position. Since each objective
has its own displacement path, they can be moved independent of one
another. As a result thereof, the possible free space compared to
objective changers having objectives that are fixedly coupled to
one another is increased even more since all objectives which are
not required can be moved into respective stand-by positions lying
outside the required free space, wherein each time space-optimized
displacement paths can be defined.
[0017] In a first embodiment, the mentioned (first) area of the
displacement path constitutes the entire displacement path from the
stand-by position to the operating position so that in the example
mentioned the objective is moved along a horizontal displacement
path from its stand-by position into the operating position. In
another embodiment, the mentioned first area is directly bordered
by a second area of the displacement path, wherein the end of the
second area can represent the operating position of the objective
or at least can lie in direct proximity to the operating position
of the objective. The provision of such a second area is
particularly advantageous in the mentioned applications of an
objective changer for a microscope in the field of
electrophysiology. The second area of the displacement path then
usefully forms the area in which the objective is moved within the
inner area of a container (Petri dish) in the direction towards or
away from the object to be examined. The displacement path within
the second area can then have a vertical movement component in
addition to the horizontal movement component in terms of vector
geometry.
[0018] In the objective changer according to the invention, each
objective has its own displacement path, wherein it is advantageous
when the displacement paths within the (first) areas lie in one
common plane and in particular extend in a straight line and/or in
a curved manner. In the example mentioned, the displacement paths
within the (first) areas thus advantageously lie in a horizontal
plane and, for example, extend in straight lines towards one
another in a fan-shaped manner. Also curved courses within the
mentioned plane are conceivable, just as is a combination of
straight and curved courses. What is decisive for the selection of
the courses of the displacement paths is that the objectives can be
transferred from their respective stand-by position into the
operating position in a collision-free manner. On the other hand,
the displacement paths must lie as close to one another as possible
so that the free working space is limited as little as possible. In
the mentioned case where they run to one another in straight lines
in a fan-shaped manner, each time two adjacent straight
displacement paths are arranged in V-shape.
[0019] The invention makes it possible to move a selected objective
individually into the operating position, while the other
objectives remain in their respective stand-by positions, wherein
these stand-by positions can be chosen sufficiently far away from
the operating position so that the objectives in stand-by do not
effectively limit the free working space. Further, it is guaranteed
that the objectives can be transferred in horizontal direction
(perpendicular to the optical axis of a microscope) and thus, for
example, away from an observing person into their stand-by
positions. Such substantially horizontally extending displacement
paths can be realized, in particular in microscopes, with a
relatively low technical expense, as will be shown by the
embodiments explained further below. The horizontal movability of
the objectives results in a far greater free space compared to
vertical displacements since the latter usually have a disturbing
effect, limit the free space and finally require a high
construction expense.
[0020] It is particularly advantageous if the displacement paths
along which the objective holders can be moved are arranged in the
changing device such that all objectives arranged in an objective
holder can simultaneously assume a respective parking position, in
particular their respective stand-by position. In this way, all
objectives can in particular be parked in a rear position as viewed
from the user. As a result thereof, the sample space becomes free
for e.g. manual manipulation.
[0021] It is advantageous if the slide of an objective or an
objective holder on which the objective is mounted can be moved
along at least one guide rod. The at least one guide rod extends
advantageously exclusively in a straight line. Of course it is
likewise conceivable that a guide rod represents the entire
displacement path of an objective from its stand-by position into
the operating position so that, as viewed from the stand-by
position, the guide rod, for example, first extends horizontally
straight (first area) to then get a vertical component (downwardly
curved second area).
[0022] Alternatively, a slide can also be movable along a guide
groove provided in an adjusting unit. In this case, the guide
groove represents the displacement path of an objective from its
stand-by position into the operating position.
[0023] What is particularly advantageous is a combination of both
features mentioned, namely that the slide is movable on the one
hand along at least one guide rod which in particular extends in a
straight line, and on the other hand that the slide is movable
along a guide groove that defines the displacement path from a
stand-by position into the operating position. For this, the slide
is in particular connected via the at least one guide rod to a
guide receptacle of an adjusting unit. Thus, the guide receptacle
so to speak holds the at least one guide rod along which the slide
moves. On the other hand, the guide groove is in particular formed
on a stationary carrier of the adjusting unit. By coupling the
slide and the guide receptacle to the guide groove in the
stationary carrier it can now be caused that the slide moves, on
the one hand, along the guide rods within the guide receptacle
(linear) while, on the other hand, it simultaneously passes through
the desired defined displacement path due to the coupling to the
guide groove in the stationary carrier. For this, the guide
receptacle of the slide must usefully be movably or pivotably
mounted in the stationary carrier. As already described, the
displacement path is advantageously comprised mainly of a
horizontally extending first area which is bordered by an angled
second area by which the objective can be brought into its final
operating position (by lowering the same). This solution makes
possible a particularly accurate and stable displacement of the
objectives.
[0024] Further, it is advantageous if for each slide an own drive
is provided. Such a drive can be provided, for example, by a
threaded spindle. Alternatively, it is also conceivable to move
several slides via one drive, wherein the moving of an objective
into the operating position would have to cause the simultaneous
moving of the other objectives into their stand-by positions, which
in particular in the case of two objectives can be realized
relatively easily. The drive can be accomplished either manually or
by a motor.
[0025] In the objective changer according to the invention, the
objectives can be moved in a fixed spatial orientation along their
displacement paths, i.e. for example with their longitudinal axis
always parallel to the above-defined optical axis. It can however
be advantageous to transport the objectives in an inclined position
from a stand-by position in the direction of the operating position
and to bring them into an upright position only after reaching the
operating position (or shortly before), in which upright position
their longitudinal axis runs parallel to the optical axis. By
providing such an inclination, the free space underneath the
objective to be moved can be increased. Further, in the mentioned
application in electrophysiology, the container edge can be easily
overcome by such an inclination so that only after reaching the
container interior the objective can be erected (corresponding to
the position in the operating position). For example, it can be
provided that the objective is moved in an inclined position over
the mentioned first area, while it already assumes an upright or at
least more upright position (corresponding to the one in the
operating position) in the mentioned second area. However it can
also be provided that the mentioned upright position is only
assumed when the operating position is reached. In order to realize
these possibilities mentioned, it is advantageous when the
objective holder is arranged so as to be pivotable on the slide and
is connected to the slide via a biasing device and/or a lever
mechanism by which the center axis of the objective holder
(corresponding to the longitudinal axis of the objective present in
the objective holder) can be held under an inclination angle
relative to the above-mentioned optical axis at least in the first
area of the displacement path.
[0026] The biasing device mentioned can be a device which holds the
objective holder, which is pivotably arranged on the slide, by
means of a (tension or pressure) spring, which is inclined relative
to the pivot axis and connects the objective holder to the slide,
in an inclined manner relative to the horizontal plane, wherein a
stop can be provided in order to limit the angle of inclination.
The longitudinal axis of an objective inserted into the objective
holder then has an angle of inclination relative to the vertical or
the optical axis which is defined by the longitudinal axis of the
objective in the operating position. When the objective reaches its
operating position, a mechanism must be provided which can bring
the objective from a possibly still inclined position into an
upright position against the spring force. Examples of such
mechanisms will be explained further below.
[0027] The lever mechanism mentioned for creating an angle of
inclination can, for example, comprise a lever pivotably mounted on
the slide, which lever interacts with a pin mounted on the
objective holder in order to create the mentioned angle of
inclination. For this, the objective holder is in turn pivotably
arranged on the slide. When using a lever mechanism, the
inclination angle mentioned can also be chosen larger so that the
objectives can be kept away as far as possible from possible
containers or objects on the sample table. For this, the lever
mechanism can be designed such that when passing through the first
horizontal area of the already mentioned guide groove of the
adjusting unit the objective is held by the lever in a highly
inclined position which can exceed the inclination caused by the
spring. When reaching the second angled area of the guide groove of
the adjusting unit, the lever starts to tilt so that the objective
leaves the highly inclined position and reduces the angle of
inclination. In the further course, the guide of the slide likewise
reaches the angled area so that, as a result thereof, a lowering of
the objective is caused, this resulting in a further reduction of
the angle of inclination. When the operating position is reached,
the angle of inclination finally is zero degree so that the
longitudinal axis of the objective coincides with the optical axis.
A specific example of such a lever mechanism is dealt with in every
detail in connection with the embodiments.
[0028] It is advantageous if the changing device of the objective
changer, in particular the mentioned adjusting units for the
objectives is or are connected to an intermediate plate on which,
for example, a centering mount for the fixed positioning of an
objective holder is arranged. The centering mount is located at the
operating position of the objective and receives the objective
holder in a defined spatial position so that an exact alignment of
the longitudinal axis of the objective along the optical axis (of
the microscope) is guaranteed. The provision of the mentioned
intermediate plate makes a modular structure of the objective
changer possible. In the mentioned example of the microscope with
objective changer, the mentioned intermediate plate can, for
example, be connected to a corresponding counter-receptacle on a
support element of the microscope via a dovetail connection. The
support element can be adjustable in focusing direction.
[0029] The invention further relates to a microscope having an
objective changer according to the invention. With regard thereto,
reference is made to the above explanations, in particular in
connection with the example of a microscope. Such microscopes
usually have a support element which is adjustable in focusing
direction and on which the changing device of the objective
changer, in particular the mentioned adjusting units, can be
mounted. In this case, a centering mount for the fixed positioning
of an objective holder is usefully arranged on the mentioned
support element of the microscope. An alternative to this
embodiment is the already mentioned modular design using an
intermediate plate. With the latter design, the centering plate can
also be mounted on the microscope (or its support element).
[0030] It is pointed out that the features of the invention and
their designs cannot only be used in the combination set forth
herein but also in other combinations or alone.
[0031] In the following, the invention and its advantages are to be
explained in more detail with reference to embodiments in
connection with the Figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] FIG. 1 is a perspective view of a microscope in which the
objective changer according to the invention can be used.
[0033] FIG. 2 is a perspective bottom view of a support element of
a microscope of FIG. 1 with an embodiment of the objective changer
according to the invention.
[0034] FIG. 3 is a perspective illustration of an adjusting unit of
an embodiment of the objective changer according to the invention
with a centering mount.
[0035] FIG. 4 shows the carrier of the adjusting unit of FIG.
3.
[0036] FIG. 5 shows the rear view of the adjusting unit of FIG. 3
without the carrier of FIG. 4.
[0037] FIG. 6 shows a detail of an embodiment of a slide with an
objective holder.
[0038] FIG. 7 shows an illustration similar to the one of FIG. 3
with an objective.
[0039] FIG. 8 shows an embodiment of an objective holder with
objective.
[0040] FIG. 9 shows a view of an adjusting unit similar to the one
of FIG. 5, wherein an objective holder with objective which is
lowered over a container can be seen.
[0041] FIG. 10 schematically shows the sequence of motions of an
objective from a stand-by position into the operating position.
[0042] FIG. 11 shows an adjusting unit of an embodiment of the
objective changer according to the invention with a lever mechanism
for inclining the objective axis.
[0043] FIG. 12 is a rear view of the illustration of FIG. 11
without the carrier of the adjusting unit.
[0044] FIG. 13 is an illustration similar to the one of FIG. 9, now
with the embodiment of an objective changer according to FIG. 11
before reaching the operating position.
[0045] FIG. 14 is an illustration like FIG. 13, in which the
operating position of the objective is now reached.
[0046] FIG. 15 shows an embodiment of an inventive objective
changer having a modular design.
DETAILED DESCRIPTION OF THE DRAWINGS
[0047] Unless described otherwise, the figures are comprehensively
dealt with in the following. The same reference signs identify the
same components. The embodiments deal with specific examples of the
invention and shall not be construed as limiting the invention. The
above explanations in connection with the claims will guide the
person skilled in the art to make generalizations and variations of
the embodiments illustrated herein.
[0048] FIG. 1 shows a microscope 1, as used in particular in the
field of electrophysiology. The support element which is adjustable
in height in focusing direction has the reference sign 2. This
support element 2 supports the objective changer with the
objectives. For the purpose of focusing, the support element 2 is
adjustable in height. A sample table with a sample placed thereon
is mounted on the table holder 34 of the vertical post of the
microscope 1. Due to the touch and vibration sensitivity of the
samples to be examined the sample table is no longer moved after
positioning. During the examinations the working distance to the
examined preparation is often very short; often the objectives can
even dip into the liquid surrounding the preparation. For the
examination of the preparations, these are usually manipulated,
i.e. via precision-mechanically formed manipulators current,
voltage or specific substances are applied to specific preparation
areas. Throughout the entire examination, these manipulators remain
in their position relative to the sample. During the examination it
is however usually necessary to change the objectives in order to
obtain different (detailed) images of the sample. The manipulations
require a large free space around the currently used objective and
the object, wherein this free space must not be limited even when
the objectives are changed since the manipulators have to be kept
in an unchanged position during an objective change.
[0049] FIG. 2 is a bottom view of the support element 2 of the
microscope 1 of FIG. 1. Therefrom, the changing device 41 of the
objective changer can be taken. In this embodiment, this changing
device 41 is designed for two objectives and thus has two adjusting
units 3a, 3b. These adjusting units 3a, 3b are mounted on the
support element 2. Each adjusting unit 3a, 3b has a drive 11 and a
slide 10 with an objective holder 15 arranged thereon. The
structure of each adjusting unit 3a, 3b will be explained in more
detail further below. Likewise illustrated in FIG. 2 is a centering
mount 4 which, in the embodiment according to FIG. 2, is fixed to
the support element 2. From FIG. 2, the arrangement of the
adjusting units 3a and 3b can clearly be seen, which both are
arranged in a V-shape relative to one another and lie in one plane
which is perpendicular to the optical axis 42 of the microscope 1
(see FIG. 1). This optical axis 42 is accordingly defined by the
longitudinal axis of an objective 19 located in the operating
position (see also FIGS. 10 and 14). Each slide 10 moves an
objective holder 15 in order to transfer the objective 19 present
in the objective holder 15 from its stand-by position into the
operating position. The stand-by positions of different objectives
are different from one another just as are the respective
displacement paths. The operating position is the position in which
the microscope 1 can provide an image of the preparation to be
examined with the aid of the objective 19.
[0050] In order to obtain a free space for preparation manipulation
that is as large as possible, the objective 19 has to be
transferred from the operating position into its stand-by position
in as little space as possible. This takes place via the adjusting
units 3a and 3b illustrated in FIG. 2, which move the objective
along a displacement path which is assigned thereto and oriented
perpendicular to the optical axis 42. Due to their own drives 11,
each objective holder can be moved independent of the other. This
independent movability likewise reduces the space requirement
compared to objective changers having fixedly coupled
objectives/objective holders. Finally, the horizontal movability
provides for a large free space compared to a vertical movability
since a vertical movability--as can be taken from FIG. 1--highly
interferes with the space between the sample table and the support
element, which space is already limited anyway. By arranging the
adjusting units 3a and 3b in a V-shaped manner, two objectives are
alternatingly moved "rearwards", as viewed from a user of the
microscope 1, thus away from the user, as a result whereof even
more free space is created. In particular, both objectives can be
moved "rearwards" into their respective stand-by position as viewed
from the user, so that both objectives are simultaneously "parked"
in their stand-by position. As a result thereof, the sample space
is free for manual manipulations.
[0051] FIG. 3 shows a detail view of an adjusting unit 3
(corresponding to the adjusting units 3a and 3b of FIG. 2).
Additionally illustrated is a centering mount 4 (similar to the
illustration in FIG. 2). The latter centering mount 4 is again
mounted on the support element 2 of the microscope 1 and is fixedly
oriented to the optical axis 42. By functional engagement between
an objective 19 and the centering mount 4 a spatially fixed
positioning of an objective 19 in its operating position is
guaranteed.
[0052] The adjusting unit 3 has a carrier 5 mounted on the support
element 2 which is adjustable in height (see FIG. 2). This carrier
5 has a bearing bore 7 in which a guide receptacle 8 is mounted so
as to be pivotable in vertical direction. This guide receptacle 8
receives the slide 10 on which the objective holder 15 is arranged.
The latter usually includes an objective thread 18 for receiving an
objective 19. The guide receptacle 8 includes at least one guide
rod 9a, 9b and a threaded spindle 11b in the case of a threaded
spindle drive 11. The slide 10 can be moved along the threaded
spindle 11b and along the guide rods 9a, 9b. The support arm 10a of
the slide 10 has a point of support 10b for the (inclined) mounting
of the objective holder 15. On this, reference will be made in
detail further below.
[0053] If a movement of an objective in horizontal direction only
is sufficient to bring an objective from its stand-by position into
the operating position, the guide receptacle 8 could be directly
fixed to the support element 2 (see FIG. 2). If it is however
desired to lower the objective in the direction of the preparation
shortly before reaching the operating position, the two-part
structure having a guide receptacle 8 that can be pivoted in
vertical direction as well as a stationary carrier 5 is
advantageous. The mode of operation will be explained in the
following.
[0054] FIG. 4 shows a perspective view of the carrier 5 of FIG. 3.
The bearing bores 7 for receiving the guide receptacle 8 in a
vertically pivotable manner are visible. On its inner side (facing
the guide receptacle 8) the carrier 5 has a guide groove 6 which
has a first horizontal area 6a and a second angled area 6b. The
horizontal area 6a serves to move the objective from its stand-by
position in the direction of the operating position along a
displacement path which is oriented substantially perpendicular to
the optical axis 42. The second area 6b serves to lower the
objective in the direction of the preparation and thus to bring the
objective into its operating position. While, in the illustration
according to FIG. 3, the slide 10 moves linearly over the
displacement area of the guide receptacle 8, the guide receptacle 8
is lowered when the angled area 6b is reached. For this, the slide
10 is oriented in the guide groove 6 of the carrier 5 via a bolt 14
projecting through a slot 12 in the guide receptacle 8, which bolt
carries a (ball) bearing 13. With respect thereto, reference is
made to the illustration according to FIG. 5, which shows a rear
view of FIG. 3.
[0055] The operation sequence is as follows: As a starting position
the rear stand-by position may be taken here in which the objective
19 is furthermost from the preparation. When starting the
adjustment, the slide 10 is set into motion by the threaded spindle
drive 11 with the threaded spindle 11b and held via the (ball)
bearing 13 so as to be oriented in the horizontal area 6a of the
guide groove 6. When the bearing 13 reaches the angled area 6b of
the guide groove 6, the guide receptacle 8 starts to pivot
downwardly about the bearing bore 7 (see FIG. 3). As a result
thereof, the inclination of the objective longitudinal axis
relative to the vertical is reduced. These two movements take place
until the objective holder comes into engagement with the centering
mount 4. The objective 19 is then in its operating position. At
this position, the bearing 13 is located outside the guide groove
6, as a result whereof the objective 19 is oriented in the optical
axis by the centering mount 4 alone.
[0056] A description of the mentioned engagement between the
objective holder 15 and the centering mount 4 is given with
reference to FIGS. 3, 7 and 8. FIG. 7 substantially shows the same
illustration as FIG. 3, wherein merely one objective 19 is mounted
on the objective holder 15. Details of the objective holder 15 are
illustrated in FIG. 8. The outside of the objective holder 15 is
cylindrical in shape with a groove 20 and a beveled side 21 and a
bottom surface 31. The centering mount 4 has a surface 32 and a
counter bearing 33. When the guide receptacle 8 lowers itself upon
reaching the angled area 6b (see FIGS. 3 and 4), then the objective
holder 15 is lowered until the surface 31 of the objective holder
15 rests on the surface 32 of the centering mount 4. The beveled
side 21 of the objective holder 15 then rests against the two
counter bearings 33 in the centering mount 4. From FIGS. 3, 7 and
8, moreover an inclined position of the longitudinal axis of the
objective 19 in relation to the optical axis 42 can be seen.
Hereto, reference is made in more detail further below. It is
however noted that such an inclined position is not a necessary
prerequisite for the objective changer illustrated here. Rather,
the longitudinal axis of the objective 19 can be oriented parallel
to the optical axis 42 during the entire displacement path. The
inclination of the longitudinal axis 19 is however advantageous in
order to bring an objective 19 over the edge of a container in
which the preparation to be examined is located while providing a
free space as large as possible. The inclined longitudinal axis of
the objective 19 then avoids an additional vertical adjusting space
which would limit the free space.
[0057] FIG. 9 shows an adjusting unit 3 of an objective changer in
which the objective 19 is in its operating position. The objective
19 is oriented in the optical axis 42 merely by the centering mount
4. The objective 19 projects into a dish-shaped container 22 in
which the preparation to be examined is contained. The first
horizontal area 6a and the second angled area 6b (with vertical
adjustment component) can be seen, the (ball) bearing 13 having
arrived at the end of the second area 6b.
[0058] One possibility of the inclination of the longitudinal axis
of an objective 19 relative to the optical axis 42 is shown in the
embodiment according to FIG. 6. As can be taken from the
illustration in FIG. 3, the slide 10 has a support arm 10a with a
point of support 10b at which an objective holder 15 is arranged so
as to be pivotable in vertical direction. Via a biasing device
comprised of a spring 16 and a stop 17 on the slide 10 the
objective holder 15 is pulled against the stop 17 in an inclined
manner by the spring force of the spring 16 mounted on the slide 10
and the objective holder 15 so that the longitudinal axis of the
objective 19 comprises an angle of inclination a with respect to
the vertical or the optical axis 42. When lowering the guide
receptacle 8 along the second angled area 6b, the angle of
inclination a is reduced until upon reaching the centering mount 4
and upon engagement between the objective holder 15 and the
centering mount 4 the angle of inclination is reduced to zero
degree.
[0059] FIG. 10 once again schematically shows the sequence of
motions of an objective 19 on its way into the operating position.
Within the first area of the displacement path an inclination of
the longitudinal axis of the objective 19 relative to the vertical
or the optical axis 42 can be seen. As can be taken from FIG. 9, a
lowering of the guide receptacle 8 (pivotably mounted about the
bearing bore 7) takes place within the second area 6b, which
results in a reduction of the angle of inclination of the objective
axis until the longitudinal axis of the objective coincides with
the optical axis 42 when the objective holder 15 and the centering
mount 4 are engaged. From FIG. 10 it can be seen that the drawn-in
measure "A" indicates the distance between the objective underside
19 in the inclined position and the one in the vertical position.
The objective 19 can consequently move over a container edge in the
inclined position and thereafter (when displaced along the second
area 6b) "dip" into the container interior. Assuming that the
objective 19 quasi sits on the sample or on the liquid surrounding
the sample, the measure A represents the height of the container
edge, which height can be overcome by the inclination of the
objective 19.
[0060] If the measure A of FIG. 10 is to be increased then at first
a higher inclination of the objective longitudinal axis is
required. This can be realized, for example, by the provision of a
lever mechanism, as will be explained with reference to FIGS. 11 to
14.
[0061] FIGS. 11 and 12 show a lever mechanism 23 to 28 for
increasing the measure A shown in FIG. 10. The lever mechanism
comprises an objective-side lever 24 which is pivotably mounted on
the axis 23 of the slide 10. A pin 26 on the objective holder 15 is
connected to an arm of the lever 24 in that the lever 24 engages
under the pin 26 and, as a result thereof, holds the objective
holder 15 in a highly inclined position. A second lever 25 likewise
mounted on the axis 23 is located on the other side of the guide
receptacle 8, i.e. on the side opposite to the slide 10. On this
second opposite lever 25, a (ball) bearing 28 is mounted via a bolt
27, which bearing--such as the bearing 13 of the slide 10--orients
itself in the guide groove 6 of the carrier 5 of the adjusting unit
3 (see FIGS. 3 and 4).
[0062] The displacement of the objective 19 from the first area 6a
of the displacement path into the second area 6b is schematically
illustrated in FIGS. 13 and 14. As long as the front bearing 28 is
located in the first area 6a, the existing highly inclined position
of the objective 19 remains unchanged. This inclination can in
particular be higher than the one achieved by the spring
arrangement according to FIG. 6 in order to be able to use other,
in particular higher cups than the usually used Petri dishes. As
soon as the front bearing 28 enters the second area 6b of the
displacement path (see FIG. 13), the lever 25 is tilted from its
horizontal position, as a result whereof the objective-side lever
24 coupled thereto is likewise tilted (downwards) and in this way
reduces the inclination (angle of inclination .alpha.) of the
objective 19. Shortly before the second (rear) bearing 13 reaches
the second area 6b of the displacement path, the angle of
inclination .alpha. has dropped to a value approximately
corresponding to the one which is chosen in the embodiment
according to FIG. 6. When the bearing 13 enters the second area 6b,
a lowering of the objective 19 with a further reduction of the
angle of inclination .alpha. takes place as a result of the
downward pivoting of the guide receptacle 8 pivotably mounted in
the bearing bore 7. In FIG. 14, the final position is shown in
which the longitudinal axis of the objective 19 coincides with the
optical axis 42 so that the objective 19 has reached its operating
position.
[0063] Finally, with reference to FIG. 15, a possible modular
structure of an objective changer is explained. Here, the adjusting
units 3 of each objective 19 are not mounted on the support element
2 of a microscope 1 (see FIGS. 1 and 2) but on an intermediate
plate 29. This intermediate plate 29 has on its upper side a
dovetail 30 which can be inserted into a corresponding counter
receptacle on the support element 2 of the microscope 1. Thus, the
intermediate plate 29 together with the corresponding connecting
piece (here dovetail 30) and the changing device 41 mounted on the
intermediate plate forms a module which, as needed, can easily be
inserted into an existing microscope 1. In the example illustrated
in FIG. 15, the centering mount 4 is fixed to the intermediate
plate 29. It can, however, also be useful to directly connect the
centering mount 4 to the support element 2 of the microscope 1 (as
in the embodiments according to FIGS. 1 and 2).
LIST OF REFERENCE NUMERALS
[0064] 1 microscope [0065] 2 support element [0066] 3, 3a, 3b
adjusting unit [0067] 4 centering mount [0068] 5 carrier [0069] 6a
first (horizontal) area [0070] 6b second (angled) area [0071] 7
bearing bore [0072] 8 guide receptacle [0073] 9a, 9b guide rod
[0074] 10 slide [0075] 10a support arm [0076] 10b point of support
[0077] 11 threaded spindle drive, drive [0078] 11b threaded spindle
[0079] 12 slot [0080] 13 (ball) bearing [0081] 14 bolt [0082] 15
objective holder [0083] 16 spring [0084] 17 stop [0085] 18 thread
[0086] 19 objective [0087] 20 groove [0088] 21 beveled side [0089]
22 dish-shaped container [0090] 23 axis [0091] 24 objective-side
lever [0092] 25 lever [0093] 26 pin [0094] 27 bolt [0095] 28 (ball)
bearing [0096] 29 intermediate plate [0097] 30 dovetail [0098] 31
bottom surface objective holder [0099] 32 surface centering mount
[0100] 33 counter bearing [0101] 34 table holder [0102] 41 changing
device [0103] 42 optical axis [0104] .alpha. angle of
inclination
* * * * *