WO2007028519A1

WO2007028519A1 - Device for the replacement of optical elements in beam paths

Info

Publication number: WO2007028519A1
Application number: PCT/EP2006/008389
Authority: WO
Inventors: Roland Scheler; Ralf Wolleschensky; Ralph Lange; Karlheinz Bartzke; Ulrich Preisser
Original assignee: Carl Zeiss Jena Gmbh
Priority date: 2005-09-10
Filing date: 2006-08-26
Publication date: 2007-03-15
Also published as: DE102005043103A1; DE102005043103B4

Abstract

The invention relates to a device for replacing optical elements in beam paths of optical apparatuses, especially for replacing color filters or splitting mirrors having different optical properties. Such a device comprises a receiving mechanism (7) for a selected optical element, e.g. a color filter (3.1), which is arranged in an illumination and detection beam path (4). Said receiving mechanism (7) is equipped with means for placing the optical element in a defined operating position. The inventive device further comprises at least one holding mechanism (9) for retaining another optical element in a standby position outside the illumination and detection beam path (4) as well as a feeding mechanism which is provided with a rotatable disk (5), for example, and is configured so as to deliver the optical elements from the standby position into the operating position and vice versa as well as orient and retain the selected optical element in the operating position within the receiving mechanism (7).

Description

Device for exchanging optical elements in beam paths

The invention relates to a device for exchanging optical elements in beam paths of optical devices, in particular for exchanging color filters or splitter mirrors, which have different optical properties from each other.

Modern optical devices for sample analysis, in particular laser scanning microscopes, are equipped in almost every optical channel with color filters and with divider mirrors, so-called dichroic mirrors. In this case, color filters and / or splitter mirrors should be interchangeable with one another in order to enable a spectral selection of the illumination and detection light as a function of the sample analysis currently to be carried out in each case.

It is known to use for changing over drives controlled, equipped with the color filters or divider mirrors change wheels.

Usually, the color filters or splitter mirror are glued to a side surface of these change wheels. Disadvantageously, ripples of these side surfaces can not be avoided due to manufacturing tolerances. These have the consequence that the angle at which the beam path is reflected at a divider mirror, deviates in the order of angular minutes from the nominal angle. Inaccuracies in the rotation of the exchange wheel by a predetermined angle of rotation when replacing color filters with each other lead to an undesirable shift of the optical axis - Z -

of the beam path. As a result, when the said optical elements are exchanged, the observation location on a sample in the range of micrometers shifts.

So far, these deviations are compensated in laser scanning microscopes by the Pinholeöffnung the laser focus is tracked. However, this requires that the Pinholesysteme must have a micrometer precisely controlled tracking and therefore are technically very complicated and expensive. In addition, the change wheels can accommodate only a limited number of splitter mirrors or color filters and therefore must be equipped with a removable device itself, which allows you to exchange several change wheels with each other and so to increase the number of available optical elements.

Based on this prior art, the present invention seeks to develop a device of the type mentioned so that positional deviations when exchanging the optical elements with each other avoided and so the disadvantages of the prior art are eliminated.

The term "position" as used herein is intended to include the meaning of the term "position" with respect to the orientation of an optical element in relation to the beam path or to the optical axis of the beam path.

According to the invention, a device for exchanging optical elements in beam paths of optical devices of the type mentioned in the introduction comprises: a receiving device for a selected optical element placed in the beam path, equipped with means for positioning it in a defined working position ensuring its correct function,

- At least one holding device for holding a further optical element in a standby position outside the beam path, and

- A feeder, the

- For feeding the optical elements from the standby position to the working position and vice versa and

- Is designed for aligning and holding the selected optical element in the working position within the receiving device.

Advantageously, this device achieves a functional decoupling of the position and orientation which the optical elements in the receiving device have from the position and orientation which they have in their ready position. Thanks to this decoupling inaccuracies of position and orientation in the standby position are not taken into the working position, but corrected due to the re-alignment taking place there.

In alternative embodiments, the means for positioning the optical element in the receiving device as

- Be carried out a the optical axis of the beam path encompassing annular cutting edge, wherein the optical element is aligned when placed on this annular cutting edge, or as - Dreipunkauflage be executed, the optical element is ELEMENT when supported on three radially symmetrical to the optical axis of the beam path arranged support points aligned.

It is advantageous if the respective optical element rests in its working position with a force in the range of 0.05 Newton to 0.15 Newton on the ring cutting edge or on the three-point support or is pressed onto the annular cutting edge or the three-point support. This ensures not only the orientation of the relevant optical element in its working position, but also the maintenance of the functional working position during use of the optical device.

Preferably, the receiving device including the means for positioning the optical element, that is, including the annular cutting edge or the three-point support, fixedly connected to the frame of the optical device. In an alternative embodiment, however, it is conceivable and is also within the scope of the invention if the receiving device including ring cutting or three-point support in the direction of the optical axis of the beam path is displaceable and the contact between ring cutting or three-point support and a selected optical element in its working position after the shift comes.

In a particularly preferred embodiment of the invention, the holding devices are movable relative to the receiving device, and the feeding device is designed so that each of the optical elements during the supply from a standby position to the working position or vice versa and during alignment in the Arbeitspositi- remains in his assigned holding device. In this regard, various embodiments of the device according to the invention are conceivable.

Thus, in a first embodiment, the feeder is equipped with

- A band on which a plurality of holding devices are strung, each holding one of the optical elements, and

- a drive including gear links

- For moving the tape including the holding devices with the optical elements relative to the receiving device until a selected optical element is positioned centrally to the optical axis of the beam path, and

- For subsequent lowering of the holding device with the centrally positioned to the optical axis of the beam path optical element until it is aligned in its working position within the receiving device.

In this case, the band may advantageously be formed as an endless belt, wherein pulleys are provided for reversing the direction of the belt movement, of which at least one deflection roller is coupled to the drive.

Furthermore, guide rollers can be provided for lowering the belt including a holding device in the direction of the receiving device. This will be explained in more detail below with reference to an embodiment. In a second embodiment, the supply device is equipped with

- A rotatable disc on which a plurality of holding devices are arranged, each holding one of the optical elements, and

- a drive including gear links

- For rotation of the disc about an axis of rotation of the optical path substantially parallel aligned axis of rotation until a selected optical element is positioned centrally to the optical axis of the beam path, and

- For subsequent lowering of the rotatable disc including the holding devices with the optical elements parallel to the optical axis of the beam path in the direction of the receiving device until the selected optical element is aligned in its working position within the receiving device.

In a third embodiment variant, the supply device is equipped with

- A magazine in which a plurality of holding devices are stored, each holding one of the optical elements, and

- A coupled with the holding devices drive including gear members

for removing a holding device with a selected optical element from the magazine,

- For its positioning centric to the optical axis of the beam path, as well

- for the subsequent lowering of the holding device with the selected optical element parallel to the op- table axis of the beam path in the direction of the receiving device until the optical element is aligned in its working position within the receiving device.

It is advantageous if the magazine is designed as a stacking magazine in which the holding devices are arranged one above the other. The gear members can then be designed to pivot out of the respective selected holding device from the magazine, and for lowering the holding device, a cam control can be provided with a positively guided in a groove sliding pin.

Within the scope of the invention is also a design variant in which the feed device is formed

- For removing the optical element from the receiving device and for storing it in a holding device, as well

- For the subsequent removal of another optical element from its holding device and for its storage and alignment within the receiving device.

In this case, the feeding device can be equipped with a gripper for removing or for depositing and thus for converting a selected optical element from its assigned holding device to the receiving device and vice versa.

Advantageously, the holding devices elastic, the optical elements on the circumference at least partially embracing material projections, which serve holding device and optical element with low manual To join force effort positively and positively and to separate again from each other.

Optionally, the device according to the invention can be equipped with sensors for detecting or checking the optical properties of the optical elements. This makes it possible in a simple manner to select, in connection with a specific examination of a sample by means of a control circuit connected to the sensors, an optical element which is suitable on the basis of its optical properties and to cause the supply to the pick-up device after selection.

In a modification of this embodiment, it is of course also conceivable that the supply of a selected optical element is caused manually and the sensors are used to check before the start of the sample examination, whether in the receiving device actually suitable for this purpose optical element is stored ,

The invention will be explained in more detail with reference to several embodiments. In the accompanying drawings show:

Fig.l known from the prior art change gear for replacing optical elements in the beam path of an optical device,

2 shows an embodiment variant of the device according to the invention, equipped with a rotatable disc on which a plurality of holding devices are arranged, each holding one of the optical elements, 3 shows a first example of the means provided in the receiving device for positioning an optical element in the form of a three-point support,

4 shows a second example of the means provided in the receiving device for positioning an optical element in the form of a ring cutting edge,

5 shows an embodiment variant of the device according to the invention, equipped with a band, on which several holding devices are lined up, each holding one of the optical elements,

FIG. 6 shows an example of a roller guide for lowering the band from FIG. 5 until the optical element held in a holding device is aligned in its working position within the receiving device, FIG.

7 shows an embodiment variant of the device according to the invention, equipped with a stacking magazine in which a plurality of holding devices are stored, each holding one of the optical elements,

8 shows an embodiment variant of the device according to the invention, equipped with a tape magazine in which a plurality of holding devices are stored, each holding one of the optical elements,

9 shows an embodiment variant of the device according to the invention analogous to FIG. 8, equipped with a wheel magazine, FIG.

10 shows an embodiment variant of the device according to the invention analogous to FIG. 8, equipped with a disc magazine, FIG.

11 shows an embodiment variant of the device according to the invention, in which the feed device is provided with a gripper for removing a selected optical element from the holding device assigned to it. direction and for storing in the receiving device or vice versa is equipped.

Fig.l shows an example of a known from the prior art change gear 1, which is rotatable about an axis 2 in the direction D and on the upper side surface more, in this case, nine color filters 3 are glued. The color filters 3 have mutually different transparency for selected wavelengths of light and are insofar characterized by differing optical properties.

The change wheel 1 is part of a microscope, for example, and serves, depending on the type of sample analysis, to set a suitable color filter 3 in the illumination and detection beam path 4. This is done by rotation of the change wheel 1 by a rotation angle which corresponds to the position of the selected color filter 3 on the change gear 1. Thus, each of the nine color filters can optionally be placed in the illumination and detection beam path 4.

The disadvantage of such an application has already been described above: due to manufacturing tolerances, the surface of the change wheel 1 is wavy, on which the color filters 3 are bonded, with the result that the optical axis of the color filter 3 to the optical axis of the illumination and detection beam path 4th is inclined. As a result, the observation location on the sample shifts in the range of micrometers each time color filters 3 are replaced with each other. If instead of the color filters 3 splitter mirrors are arranged on the change gear, problems with similar consequences occur because the splitter surfaces are not always are aligned perpendicular to the illumination and detection beam path 4 and therefore the reflection angle of each set in the illumination and detection beam 4 beam splitters differ from each other.

Remedy is far created by the focus position is corrected in a complex manner. For laser scanning microscopes, a pinhole system is required for this correction, in which the pinhole opening can be tracked to the laser focus with micrometer precision. Such a system is relatively expensive, bulky and costly.

In order to remedy these disadvantages, a device for exchanging optical elements in beam paths of optical devices is provided according to the invention, as shown in a first embodiment variant in FIG.

2 shows a feeding device which has a rotatable disk 5 on which a plurality of holding devices are arranged, by means of which optical elements are held, which in turn are, for example, color filters 3. The disc 5 is rotatable about an axis 6 and also arranged displaceably in the direction of the axis 6. Direction of rotation D and displacement direction R are symbolically indicated in Figure 2 by double arrows.

As is further apparent from FIG. 2, a receiving device 7 is present, which is provided here by way of example with a three-point support for a color filter 3, wherein three support points 8 define the functional working position of the color filter 3 in the illumination and detection beam path 4. In the representation selected in FIG. 2, the color filter 3.1 selected in this case is in a position with centric alignment with the illumination and detection beam path 4 after corresponding rotation of the disk 5, but at a distance a from the three support points 8.

In order to bring the color filter 3.1 in the defined working position or to rest on the support points 8, a coupled via gear members with the disc drive 5 (not shown in the drawing) is present, for the displacement of the disc 5 including the holding devices thereon with the color filters 3 in the direction of displacement R lowered until the color filter 3.1 comes to rest on the support points 8.

How this compensates the manufacturing tolerances described above and the disadvantages of the prior art are eliminated, will be explained below with reference to Figure 3 and Figure 4.

In Fig.3a, the situation is shown in principle, which corresponds to the representation in Figure 2. Evident is a section of the rotatable disk 5 with an integrated holding device 9, which is designed to receive the color filter 3, in this case the color filter 3.1. The rotatable disc 5 consists essentially of a less elastic material, preferably a plastic with a modulus of elasticity in the range of 1000 N / mm ² . The holding device 9 is made of material having a greater elasticity, for example a plastic having a modulus of elasticity in the range of 10,000 N / mm ² . The optical axis 10 of the color filter 3.1 is inclined to the optical axis of the illumination and detection beam path 4 by an angle α, which here, as well as the waviness of the disc 5, exaggerated to demonstrate the given in practice unwanted angular deviation.

As already stated, now the disc 5 is lowered in the direction of displacement R until the color filter 3.1 comes to bear against the support points 8 of the receiving device 7, as shown in Fig.3b. The displacement of the disc 5 takes place until the color filter 3.1 rests with a contact force on the support points 8, which is tuned to the elasticity of the material of the disc 5 and should be in the range of 0.05 Newton to 0.15 Newton. Due to this force effect, the disturbing waviness of the disc 5 is compensated, the angle α goes to 0 °.

The receiving device 7 is arranged fixed to the frame in the relevant optical device including the support points 8 and defines due to the immovable position in the illumination and detection beam 4, the functional working position of the color filter 3.1.

The elasticity of the material from which the holding device 9 is made, allows the removal or insertion of color filters 3 in the holding device 9 with little manual effort. The color filter 3 are held positively and positively in the holding device 9. FIG. A shows an alternative embodiment to the receiving device 7 according to FIG. 3, in which instead of the three support punches 8 a ring cutting edge 11 is provided. Here, the working position of the color filter 3.1 is given when the color filter 3.1 rests on the annular cutting edge, as can be seen from the illustrations according to Fig.4a and Fig.4b.

A second embodiment variant of the device according to the invention is shown in FIG. Here, the feeding device is equipped with a band 12 on which a plurality of holding devices are lined up, each of which holds one of the optical elements, here for example color filters 3 again. The belt 12 is designed as an endless belt and passes over two deflection rollers 13 and 14, of which at least one deflection roller 13 is coupled to a (not shown) rotary drive.

If the rotary drive is turned on, the holding devices (not shown here in the drawing) move with the color filters 3 in the feed direction V and run successively through the illumination and detection beam path 4. If the color filter 3.1 selected for a particular sample analysis reaches the illumination and detection beam path 4, as shown in Figure 5, the rotary drive is stopped. Now, the color filter 3.1 is analogous to the representation in Figure 2 at a distance a above the receiving device 7, which is to be provided in this case with a ring cutting edge 11, wherein here only the annular cutting edge 11 is shown symbolically.

The manner in which the distance a is bridged and the color filter 3.1 is brought to rest on the annular cutting edge 11 can be seen in FIG. 6 shows a device 15 for guiding the band 12, which is arranged between the deflection rollers 13 and 14 at the position of the illumination and detection beam path 4 (see FIG.

As can be seen from FIG. 6, in the device 15, the band 12 runs on both sides of the holding device 9 through pairs of guide rollers 16.1, 16.2 and 17.1, 17.2. The device 15 is arranged displaceably in the direction R and coupled for the purpose of displacement in the direction R with a (not shown in the drawing) drive including associated gear members.

If the selected color filter 3.1 has reached the position shown in FIG. 5 with respect to the illumination and detection beam path 4, the drive for shifting the device 15 is put into operation and thus the strip 12 including the holding device 9 with the color filter 3.1 is lowered so far, until the color filter 3.1, again with a force in the range of 0.05 Newton to 0.15 Newton, rests on the annular cutting edge 11 and has assumed its working position in the illumination and detection beam path 4.

7 shows a further embodiment variant of the device according to the invention with a feed device, which is equipped in this case with a stacking magazine 18, in which a plurality of holding devices 9 with optical elements, for example, again with color filters 3, are stored. The stack of holding device 9 is coupled to a (not shown in the drawing) drive and associated gear members, which are designed so that Optionally, a holding device 9 can be pivoted out of the stack into the illumination and detection beam path 4.

For the purpose of swinging out the holding devices 9 are rotatably mounted in the direction B about a straight guide 19, on which they are lined up. After swinging out, the holding device 9 with the selected color filter 3.1, analogous to the illustrations in Figure 2 and Figure 5, again at a distance a above the receiving device 7, which is here again exemplified with a three-point support.

The stack of holding devices 9 is displaceable parallel to the illumination and detection beam path 4, so that the lowering of the stack and thus also of the color filter 3.1 to the orientation in the working position takes place with the already mentioned and not graphically illustrated drive or the associated gear members , Since here again the circulation takes place under a force, position deviations of the color filter 3.1 are compensated due to this force.

FIG. 7b symbolically shows a top view of the stack and the pivoted holding device 9 with the selected color filter 3.1. Here again the direction B is shown, around which the holding devices 9 are individually pivotable.

In Figure 8, the variant of a supply device is shown, which is provided with a tape magazine. In this tape magazine in turn several holding devices 9 with optical elements, preferably color filters 3, stored. The holding devices 9 are arranged on an endlessly circulating belt 12 whose feed direction V is deflected by means of two deflection rollers (which are not shown in the drawing) to two reversing positions. The holding devices 9 with the color filters 3 run around with the tape 12 and are arranged on the belt 12 so that their optical axes are always aligned parallel to the feed direction V. The feed direction V, in turn, runs parallel to the illumination and detection beam path 4.

When the holding devices 9 equipped with a color filter 3.1 selected for a specific microscopic examination reaches the position between two side parts of a slide 23 designed as cheeks 22.1 and 22.2 during rotation of the belt 12, the circulation is stopped. The with a (not shown in the drawing) drive coupled slider 23 is set from this position, which corresponds to a first end position in the direction of displacement R in motion, the cheek 22.1 comes to rest on the respective holding device 9 and so the holding device 9 in the direction of displacement R. is taken with the movement of the slider 23 until the slider 23 is in a second end position. With the displacement of the holding device 9, the displacement of the color filter 3.1, wherein the optical axis of the color filter 3.1 is offset in parallel takes place. In the second end position of the slider 23, the optical axis of the color filter 3.1 is aligned substantially centrally to the illumination and detection beam 4.

Centrally to the illumination and detection beam 4 is a receiving device equipped with a radial three-point system, of which only the three arranged radially symmetrically to the optical axis of the beam path 4 contact points 26 are shown.

With the reaching of the end position of the slider 23, the color filter 3.1, which is elastically received in its associated holding device 9, with a contact force, which is in the aforementioned embodiments in the range of 0.05 N to 0.15 N, between the received three investment points 26 and thereby assumes its functional work position.

The return of the color filter 3.1 in its position on the belt 12 takes place in the reverse manner. Thus, depending on the choice, the various holding devices 9 arranged on the belt 12, including the color filters 3 assigned to them, can be positioned exactly in the illumination and detection beam path 4.

9 shows the variant of a feeding device analogous to Figure 8, but equipped with a wheel magazine instead of the tape magazine. On the rotating in the direction of rotation D wheel 24 a plurality of optical elements, preferably color filters 3, equipped holding devices 9 are arranged. When a holding device 9 equipped with a selected color filter 3.1 reaches the position between the two cheeks 22.1 and 22.2 of a slide 23 during rotation of the wheel 24 (analogously to FIG. 8), the circulation is stopped. The removal of the selected color filter 3.1 from the wheel magazine whose positioning is centered to the illumination and Detektionsi- onsstrahlengang 4 and its alignment by means of three contact points 26 in the functional working position as in the embodiment described with reference to Figure 8, as well as the return of the Example, as the return of the holding device 9 with the color filter 3.1 in its position on the wheel 24th

In Fig.10 another variant of the feeder is shown, in this case with a disc magazine. Again, with the rotation of the disk 25, the holding device 9 is brought with the selected color filter 3.1 between the two cheeks 22.1 and 22.2 of the slider 23 and then the slider 23 is set in motion, whereby the optical axis of the color filter 3.1 is offset parallel until they is aligned centrally to the illumination and Detektionsstrahlen- gear 4. The alignment of the color filter 3.1 in its exact working position and the subsequent return to the disc magazine is analogous to the embodiments according to Fig.8 and Fig.9.

11 shows an alternative embodiment to the aforementioned examples, in which the feed device is designed to remove a selected optical element, for example a color filter 3.1, from the assigned holding device 9 (which is likewise not shown here) and to deposit it in the receiving device 7. The removal and removal of the color filter 3.1 is effected by means of a pivotable about a pivot axis 20, while a circular arc C descriptive (not shown) gripper, which holds the color filter 3.1 during the pivoting.

In order to be able to place one of the selected color filters 3 in a position in which it can be picked up by the gripper and removed from the holding device 9 assigned to it, it is conceivable to integrate the holding devices 9 in turn into a rotatable disk 5 whose Rotary axis, as exemplified here, may lie in the optical axis of the illumination and detection beam path 4.

In all described embodiments, sensors 21 may be provided for detecting or controlling the characteristic optical characteristics of the color filters or splitter mirrors, the sensors 21 being coupled to a drive circuit for selecting or controlling these characteristics in connection with certain applications of the optical device.

LIST OF REFERENCE NUMBERS

1 change wheel

2 axis

3, 3.1 color filter

4 illumination and detection beam path

5 rotatable disc

6 axis of rotation

7 pick-up device

8 support points

9 holding device

10 optical axis

11 ring cutter

12 band

13, 14 Uinlenkrollen

15 Belt guide device

16. 1, 16.2 Guide rollers

17. 1, 17.2 guide rollers

18 stacking magazine

19 Straight Guide

20 pivot axis

21 sensors

22. 1, 22.2 cheeks

23 slides

24 wheel

25 disc

26 investment points

α angle a distance

B direction of rotation

C circular arc

D direction of rotation

R shift direction

V feed direction

Claims

- 1 - Patent claims

1. Device for replacing optical elements in beam paths of optical devices, in particular for replacing color filters (3) or splitter mirrors each with different optical properties in microscope beam paths, comprising: a receiving device (7) for a selected optical element placed in the beam path, equipped with Means for positioning it in a defined working position that ensures its correct function, at least one holding device (9) for holding a further optical element in a standby position outside the beam path, and - a feed device, which

- Is designed to align and hold the selected optical element in the working position.

2. Device according to claim 1, characterized in that the means for positioning the optical element in the recording device are designed as

- an annular cutting edge (11) encompassing the optical axis of the beam path, the optical element being aligned when resting on the annular cutting edge (11), or as

- Three-point support, whereby the optical element is radially symmetrical to the optical when supported on three points - 2 -

Axis of the beam path arranged support points (8) is aligned, or as

— Three-point system, whereby the optical element is aligned when it is in contact with three contact points (26) arranged radially symmetrically to the optical axis of the beam path.

3. Device according to claim 2, in which the optical elements rest on the ring cutting edge (11) or the three-point support (8) with a contact force in the range of 0.05 Newton to 0.15 Newton.

4. Device according to claim 2, in which the optical elements rest with a contact force in the range of 0.05 Newton to 0.15 Newton between the contact points (26) arranged radially symmetrically to the optical axis of the beam path.

5. Device according to one of the preceding claims, characterized _in that the receiving device (7) is arranged fixed to the frame and the working position of the optical element is thereby defined.

β. Device according to one of the preceding claims, in which the receiving device (7) and the holding devices (9) are movable relative to one another and the feeding device is designed such that each of the optical elements is moved from the standby position to the working position or vice versa during feeding, as well as during remains in its assigned holding device (9) during alignment in the working position. - 3 -

Device according to claim 6, in which the feed device is equipped with a belt (12) on which a number of holding devices (9) are lined up, each holding one of the optical elements, a drive including gear members

- for moving the band (12) including the holding devices (9) with the optical elements relative to the receiving device (7) until an optical element selected based on its optical properties is positioned centrally to the optical axis of the beam path, and

- for the subsequent lowering of the holding device (9) with the optical element positioned centrally to the optical axis of the beam path until it is aligned in its working position within the receiving device (7).

Device according to claim 7, wherein the belt (12) is designed as an endless belt and is guided by means of deflection rollers (13, 14), of which at least one deflection roller (13) is coupled to the drive.

Device according to claim 6, in which the feed device is equipped with a rotatable disk (5) on which a plurality of holding devices (9) are arranged, each holding one of the optical elements, and a drive including gear members

- To rotate the disk (5) about an axis of rotation (6) that is essentially parallel to the optical axis of the beam path, until a selected one - 4 -

optical element is positioned centrally to the optical axis of the beam path, as well

- for lowering the rotating disk (5) including the holding devices

(9) with the optical elements parallel to the optical axis of the beam path in the direction of the recording device (7) until the optical element is aligned in its working position within the recording device (7).

10. Device according to claim 6, in which the feed device is equipped with

- a magazine in which several holding devices (9) are stored, each holding one of the optical elements, and

- A drive including gear members coupled to the holding devices (9).

- for removing a holding device (9) with a selected optical element from the magazine,

- for its positioning centrally to the optical axis of the beam path, as well

- for the subsequent lowering of the holding device (9) with the selected optical element parallel to the optical axis of the beam path in the direction of the recording device (7) until the optical element is aligned in its working position within the recording device (7).

11. Device according to claim 10, in which the holding devices (9) are stacked in the magazine, the gear members for pivoting out the holding devices (9) with the selected optical element from the magazine. - 5 -

are formed, and for lowering the holding device (9) there is a cam control with a sliding pin forcibly guided in a groove.

12. Device according to one of claims 1 to 5, in which the feed device is formed

- for removing the optical element from the receiving device (7) and placing it in a holding device (9), as well

- for subsequently removing a further optical element from its holding device (9) and for storing and aligning it within the receiving device (7).

13. Device according to claim 12, in which the feed device is equipped with a gripper for removing or depositing and thus for moving a selected optical element from the holding device (9) assigned to it to the receiving device (7) or vice versa.

14. Device according to one of the preceding claims, characterized in that the holding devices (9) have elastic material elevations which at least partially surround the optical elements on their circumference, through which the holding devices (9) and the optical elements are force- and can be connected in a form-fitting manner.

15. Device according to one of the preceding claims, characterized in that color filters (3) or splitter mirrors are provided as optical elements and the device with sensors (21) for determining or con- - 6 -

Troll characteristic optical properties of the color filters (3) or splitter mirrors are equipped, the sensors (21) being coupled to a control circuit for specifying these properties in connection with certain applications of the optical device.