WO2007098821A1

WO2007098821A1 - Multispectral illumination apparatus

Info

Publication number: WO2007098821A1
Application number: PCT/EP2007/000131
Authority: WO
Inventors: Christian Dietrich
Original assignee: Carl Zeiss Jena Gmbh
Priority date: 2006-02-27
Filing date: 2007-01-09
Publication date: 2007-09-07
Also published as: DE102006009053A1

Abstract

An illumination apparatus for emitting optical radiation through at least one coupling-out interface comprises at least two radiation sources (6) for emitting optical radiation in respectively different wavelength ranges, at least one optical deflection device (9), which can be rotated or pivoted about a prespecified axis (10) relative to the radiation sources (6), for the emitted optical radiation and a drive device (11) for rotating or pivoting the deflection device (9) about the axis (10), wherein the radiation sources (6) are arranged relative to the deflection device (9) and the axis (10) such that optical radiation emitted by each of the radiation sources (6) can be deflected into the coupling-out interface by the deflection device (9) which is rotated or pivoted about the axis (10) into a suitable angular position.

Description

Multispectral illumination device

The present invention relates to a multi-spectral illumination device, optical devices, in particular imaging, examination, observation and projection devices, with such a lighting device and a method for providing optical radiation.

An important field of use of illumination devices are imaging devices which are intended to generate images of an object or a sample to be examined. Typical examples of such imaging devices are microscopes and in particular microscopes with a wide-field optics, which images a given region of the sample to be imaged, and not just a small punctiform region of the sample, onto an image plane. The illumination device serves to provide optical radiation in a desired wavelength range for illuminating the object or the sample. By optical radiation is meant in particular electromagnetic radiation having wavelengths in the range from the ultraviolet to the infrared part of the spectrum.

For many applications in far-field microscopy, it is necessary to illuminate or illuminate the samples in a defined sequence that is as fast as possible using optical radiation of different color or wavelength. Preferably, the switching between different colors or wavelength ranges within milliseconds and a modulation of the intensity of the sample illumination should be possible within microseconds.

A special role is played in the optical examination of samples from the fluorescence assay. In this case, the sample is irradiated with excitation radiation in a suitable excitation wavelength range or with a suitable excitation spectrum, which is selected as a function of one or more fluorescent dyes. If these fluorescent dyes are present in the sample, they interact with the excitation radiation and emit fluorescence radiation that is characteristic of the fluorescent dye. In this way, a detection of fluorescent dyes in a sample is possible. In this case, not only the presence of fluorescent dyes or substances to which the fluorescent dyes are bound, but also their concentration can be determined.

An important field of application of fluorescence studies is molecular biology. In this case, fluorescent dyes are used which specifically bind to predetermined substances in a biological sample and can then be detected in the bound state. It is thus possible to infer the presence and concentration of the given substance in the sample. For such investigations, so-called fluorescence readers are used, which are designed for the investigation of biochips with several, usually even very many, mutually delimited areas, each with a different chemical composition. Such devices are used to examine a large number of samples as possible in an investigation on several different fluorescent dyes.

For rapid examination of samples, it would therefore be desirable to use an Abbildungsbzw. To have an examination device that allows a quick change between the different spectra.

For this purpose, it is possible, for example, to use a multispectral illumination device with which at least sequentially optical radiation can be emitted in at least two different wavelength ranges. In this context, sequential release of optical radiation in at least two different wavelength ranges means that optical radiation is emitted in succession for a given period of time, the intensity of which in each of the wavelength ranges is at least one pronounced maximum, the intensity not necessarily being in the range must disappear between the two wavelength ranges.

One possibility for multispectral illumination is the use of white light sources, from the optical radiation of which a desired range is selected. For this purpose, for example, the optical radiation can be spatially split by means of a dispersive element. By using a suitably arranged aperture or an aperture wheel, a desired spectral component of the optical radiation can then be selected. This approach has the disadvantage that a change between different wavelength ranges is expensive. In addition, the use of dispersive elements is relatively expensive and expensive and also not very effective in terms of radiation yield. Another possibility is to filter only a certain desired wavelength range, for example by means of a color filter or a dichroic. For changing the wavelength ranges, it is possible, for example, to use filter wheels which, however, due to the moving mass, do not permit a rapid change between the wavelength ranges.

Another possibility is the use of tunable liquid crystal filters, which indeed dodge a quick change and are flexible, but are expensive and expensive to produce. In addition, they offer only a very limited transmission, often smaller than 50%, so that here too the radiation yield is low.

A general disadvantage of using a white light source is that the switching on and off as well as a modulation of the intensity can not be done very quickly, since these radiation sources are very sluggish. For this purpose, mechanical closures and gray filters are necessary, which entail a complex construction.

Another possibility is to use several colored radiation sources, i. To use sources of optical radiation that emit optical radiation in each different wavelength ranges or with different characteristic wavelength.

Thus, DE 103 14 125 A1 describes an arrangement for illuminating objects with light of different wavelengths in microscopes, automatic microscopes and devices for fluorescence microscopy applications, comprising LED light sources for object illumination, which are arranged in the illumination beam path of the microscope or device. For moving at least one of the light-emitting diodes into an illumination beam path, a receiving device rotatable about an axis of rotation is provided with holders for at least one of the light-emitting diodes. By means of a drive device, the recording device is adjustable so that the LED can be moved with the respective required for measurements and / or observations focus wavelength in the illumination beam path. However, this concept has the disadvantage that the rotatable receiving device with light-emitting diodes held therein has a considerable mass, which does not allow a very rapid change between the wavelength ranges readily.

The present invention is therefore an object of the invention to provide a lighting device for the sequential emission of optical radiation in each different predetermined wavelength ranges, which is simple in construction and a rapid change of the wavelength range of the radiation emitted by her dust, and a method for Provide optical radiation in at least two different wavelength ranges.

The object is achieved by an illumination device for emitting optical radiation through at least one decoupling interface with at least two radiation sources for emitting optical radiation in respectively different wavelength ranges, at least one optical deflection device for deflection about a predetermined axis relative to the radiation sources the emitted optical radiation and drive means for rotating the deflection means about the axis, the radiation sources being disposed relative to the deflection means and the axis such that optical radiation emitted by each of the radiation sources is rotated about the axis in an appropriate angular position or pivoted deflection can be deflected into the decoupling interface.

The object is further achieved by a method for the sequential provision of optical radiation in at least two different wavelength ranges in a predetermined time change through at least one decoupling interface, in particular using a lighting device according to the invention, in which with at least two radiation sources, each of which optical radiation in one another of the wavelength ranges, optical radiation is generated in one of the wavelength ranges and directed to an optical deflection device, and the optical deflection is rotated or pivoted relative to the radiation sources so that in the predetermined time change optical radiation of the different wavelength ranges in the Decoupling interface is deflected.

The illumination device is therefore intended to emit optical radiation through a decoupling interface. In the context of the present invention, a decoupling interface is understood as meaning a predefined area of the illumination device or a surface positioned fixedly relative to the illumination device, through which optical radiation is emitted in a direction predetermined by at least one part of the illumination device. In this case, in the case of a radiation beam emitted, the direction is understood to mean the direction of the beams of the beam, averaged over the cross section of the emitted radiation beam.

The radiation sources are designed to emit optical radiation in respectively different wavelength ranges, ie they each have different emission spectra. This is understood to mean that the characteristic wavelengths of the respective emission spectra, for example intensity maxima of the respective emission spectra or heavy point wavelength of the respective emission spectra or their dominant wavelengths, from each other, preferably spaced by more than 50 nm. In particular, emission peaks of the radiation sources do not overlap at least within the half-value width of the peaks, or only in the flanks of the emission peaks. The radiation sources emit optical radiation of different "color".

In order to select a predetermined wavelength range from the wavelength ranges predetermined by the radiation sources, optical radiation is emitted by the corresponding radiation source in the direction of the deflection device. The deflection device is brought into a position by turning or pivoting in which the optical radiation of the selected radiation source is deflected by the deflection device into the decoupling interface.

The movement of the deflection device takes place in the device by means of the drive device, which can for this purpose comprise an actuator or actuator which can be controlled by control signals.

The lighting device is characterized by a very simple structure and in particular does not need to have moving mechanical components with large mass or large moment of inertia, since optical deflection can be very light and already rotation around a very small angle can be sufficient to instead of radiation first of the radiation sources to direct radiation of a second of the radiation sources in the decoupling interface. This allows a very fast change between the wavelength ranges.

Since the radiation sources need not be moved, in principle any radiation sources can be used which can deliver optical radiation in the desired wavelength ranges. In a preferred embodiment of the illumination device, the radiation sources comprise at least one radiation source whose radiation is emitted to the deflection device via fiber optics. In the method, a radiation source whose radiation is emitted to the deflection device via fiber optics is then preferably used as at least one of the radiation sources. This allows in particular to use even bulky radiation sources whose optical radiation can then be brought by the fiber optics in a spatially small area near the deflection device.

In a preferred embodiment of the device, the radiation sources preferably comprise at least one laser. In the method, a laser is preferably used as at least one of the radiation sources. This has the advantage that through the laser Particularly intense and / or narrowband and / or coherent radiation can be delivered compared to other radiation sources.

In the apparatus, the radiation sources particularly preferably comprise at least one semiconductor radiation source. In the method, a semiconductor radiation source is then preferably used as at least one of the radiation sources. This embodiment has a number of advantages. So build semiconductor radiation sources very compact, so that the lighting device itself can also be made compact. Further, there are available semiconductor radiation sources which provide optical radiation in narrow wavelength ranges, i. emitted colored optical radiation. By choosing appropriate semiconductor radiation sources very different wavelength ranges can be covered. Compared to conventional light sources such as arc or halogen lamps, the use of semiconductor radiation sources, in particular light emitting diodes, moreover has the advantage that they have a much longer life. Furthermore, the heat generation by semiconductor radiation sources during their operation is much lower than with arc or halogen lamps. An active cooling of the semiconductor radiation sources can therefore be omitted, a passive cooling can be significantly simplified compared to the use of arc or halogen lamps. Preferably, all radiation sources are semiconductor radiation sources.

The semiconductor radiation sources may be any semiconductor devices emitting optical radiation. For example, laser diodes or superluminescent diodes can be used. Preferably, however, light-emitting diodes or light emitting diodes or organic light-emitting diodes are used. Particular preference is given to high-performance light-emitting diodes which emit optical radiation of high intensity. Preferably, powerful colored light-emitting diodes are used for the lighting device. In order to cover predetermined wavelength ranges, light-emitting diodes with applied phosphors for color conversion, which emit optical radiation in another wavelength range excited by optical radiation emitted by the semiconductor material of the light-emitting diodes, can also be used. Compared to the use of conventional lasers, semiconductor radiation sources, in particular light-emitting diodes, have the advantage that their emission spectra are broadband than many lasers, so that it is easier to filter out a certain desired proportion by means of suitable filter selection. Also, the problems that occur in ordinary lasers due to the high coherence of the laser radiation, such as speckle formation, do not occur or not so pronounced.

The light-emitting diodes may in particular be those having a plane surface from which the optical radiation emerges or light-emitting diodes having a transparent dome arranged above the surface for reducing the refractive index jump to the semiconductor material. your. The use of four semiconductor radiation sources allows good coverage of a given spectral range, in particular the entire optical spectrum, in particular the visible spectrum as well as the UV and NIR range. For this purpose, at least one of the semiconductor radiation sources is preferably a UV or NIR radiation source with a characteristic emission wavelength in the UV or NIR range. In order to be able to provide sufficient radiation power in the respective wavelength range for the respective application, it is also possible to use a corresponding field of identical semiconductor radiation sources instead of just one semiconductor radiation source for a given emission wavelength range. For example, a field of the same light emitting diodes can be used.

Semiconductor radiation sources have not yet been available at economically acceptable cost for any emission wavelength range. It is therefore preferred that the illumination device comprises at least one semiconductor radiation source with at least one phosphor for color conversion, in the beam path of which a band-pass filter is arranged and whose radiation is likewise emitted to the deflection device. The bandpass filter is preferably located between a collimation device associated with the semiconductor radiation source and the semiconductor radiation source itself. A color conversion by a phosphor is understood to mean that the phosphor emitted by a radiation-emitting layer of the semiconductor radiation source by fluorescence and / or phosphorescence in radiation in the desired wavelength range, ie Radiation of other color, converted. The bandpass filter is chosen so that the radiation of the semiconductor radiation source is limited spectrally to a suitable wavelength range. Preferably, that range is in the range of 570 nm. This embodiment has the advantage that gaps in the wavelength range of the optical spectrum that can be covered by semiconductor radiation sources can be filled by using a corresponding bandpass filter.

In principle, the radiation sources can be arranged as desired, as long as their radiation can be deflected by the deflection in a suitable position in the decoupling interface. Preferably, however, the radiation sources are arranged in one plane. In this case, then the axis about which the deflector can be pivoted or rotated, is orthogonal to the plane. This allows a very simple structure can be achieved by the radiation sources are arranged, for example, on a circuit board. Furthermore, the adjustment of the arrangement of the radiation sources relative to the deflection device or the axis is particularly simple.

Particularly preferably, the radiation sources are arranged on a circular arc. In particular, the pivoting or pivoting axis can then run through the center of the circular arc orthogonal to the plane spanned by the circular arc. This embodiment has the advantage that the optical paths from the radiation sources to the deflection device in this case are the same length, so that intensity losses on the way from the radiation sources and the deflection are equally strong.

Since, in particular, semiconductor radiation sources do not necessarily deliver the optical radiation in a concentrated manner, at least one collimation device for collimating the radiation emitted by the radiation source and / or a filter for limiting the spectrum of the radiation impinging on the deflection device can be provided in the beam path between at least one of the radiation sources and the deflection device , For example, a narrow bandpass filter, be arranged. The collimation has the advantage that on the one hand a collimated beam can be deflected defined and less losses than a divergent, and that on the other hand, the resulting at collimation at least quasi-parallel beam allows the use of interference filters that besoη _{% of it} precise Dust filtering. By way of example, the collimation device may comprise at least one concentrator or a holographic or diffractive element which deadens a collimation of the optical radiation emitted by the respective radiation source. Preferably, however, at least one of the collimating means comprises an aspherical lens or an aspherical mirror. This embodiment of the collimation device has the advantage that the aspherical design permits a particularly good bundling of the optical radiation emitted by the respective radiation source, in particular the semiconductor radiation source, and thus radiation losses can be reduced by a less directed radiation of the optical radiation from the semiconductor radiation source. In this case, the filter serves to mask out long spectral outlets of the emission spectra of the radiation sources, in particular of the semiconductor radiation sources, and thus to possibly avoid disturbing background signals. This has the advantage that a later evaluation in a fluorescence examination is facilitated. The bandpass filter preferably has a spectral width of less than 100 nm.

The deflection device has at least one deflection element which deflects radiation incident thereon. A deflection is generally understood to mean that radiation incident from one direction is generated in a different direction, not only diffusely scattered radiation. The deflection device can therefore preferably comprise at least one of the following deflection elements or also a combination of at least two of these deflection elements.

Thus, the deflection device of the device can have a prism as deflecting element. However, it is also possible that the deflection device as deflecting a diffractive element having. This can in particular be a diffraction grating. Preferably, the deflection device has at least one mirror as a deflecting element. The use of a mirror has the advantage that a very high proportion of the incident radiation is actually deflected and the deflection takes place largely independently of the wavelength of the incident radiation. In addition, mirrors can have a very low moment of inertia, so that a fast rotation is possible.

For the movement of the deflection device, the drive device is used, which can have an actuator which can be controlled via control signals or an actuator which can be controlled via control signals, for example an electric motor or a galvano drive, by means of which the deflection device can be placed in a position corresponding to the control signal. The device then preferably also comprises a control device for activating the drive device in order to move the deflection device into at least two positions in which these optical radiation in each case redirects another of the radiation sources into the outcoupling section parts.

In principle, it is sufficient that the control device is designed to control the drive device. Then, the radiation sources can be operated simultaneously, the selection of wavelength ranges then takes place solely by movement of the deflection. However, it is preferred that the control device is also designed to control the radiation sources.

In particular, the control device may be further configured and connected to the radiation sources, that by means of the control device, the intensity and / or radiation duration of the emitted from the radiation sources optical radiation for at least two of the radiation sources is separated from each other adjustable. In the method, the intensity and / or emission duration of the optical radiation emitted by the radiation sources can then be set separately for at least two of the radiation sources. This embodiment has the advantage that the radiation powers of the individual radiation sources, in particular of semiconductor radiation sources, in contrast to arc or halogen lamps, without a change in the color spectrum can be accurately adjusted. In particular, it is possible to adjust the radiation powers so that the optical radiation emitted by the radiation sources into the coupling-out interface has the same radiant power in each case. Also, a modulation of the radiation power is possible. For this purpose, the control device can have corresponding operating elements to be operated by a user, for example switches. Preferably, however, a control input is provided, by means of which the control device can receive control signals to which the control device switches on and off one or more of the radiation sources and / or the deflection device by means of disconnection. There would be corresponding signals to the drive means in a suitable angular position brings. The radiation sources can be switched on and off individually or in combination.

Particularly preferably, the control device is further configured such that it synchronously or synchronously turns on one of the radiation sources and rotates or swings the deflection device into a position by emitting signals to the drive device in which this optical radiation of the switched radiation source deflects to the coupling-out interface. In the method, to synchronize or synchronize the wavelength ranges, one of the radiation sources is switched on and the deflection device is rotated or swiveled into a position in which this optical radiation of the switched-on radiation source deflects onto the coupling-out interface. This has the advantage that in the time in which the radiation of the radiation source is deflected into the Auskoppelschnittstelle, the other radiation sources can be switched off or kept switched off, to which the control device can be designed accordingly. As a result, disturbing background radiation, which could reach the area to be illuminated by emitting radiation in the unwanted wavelength ranges, as well as unwanted heat generation can be avoided. Under a synchronized switching is understood in particular that synchronization can be done by appropriate external synchronization signals.

The adjustment of the position of the radiation sources and the decoupling interface and the positions of the deflection device to each other can be done for example by mechanical means. Preferably, however, the control device is further configured such that the position of the deflection device for the deflection of the optical radiation of one of the radiation sources to the decoupling interface is electronically adjustable. The Justiermöglichkeit needs to be possible only in a predetermined range by a mean angle at which the radiation of the radiation source would ideally be directed into the decoupling interface.

For many lighting purposes, it is desirable to be able to use optical radiation with a constant intensity which is good enough over the beam or beam cross section. For this purpose, a homogenization device is preferably arranged in the beam path between the deflection device and the decoupling interface. In the method, the radiation to be emitted is preferably homogenized before it reaches the decoupling interface. In particular, transparent rods or hollow rods with reflective side walls, diffractive optical elements or diffusing disks can be used as the homogenizing device. The use of bars with reflective walls has the advantage that the losses therein are particularly low. Alternatively or additionally, however, in the illumination device for homogenizing the radiation to be emitted by the decoupling interface of at least one of the radiation sources, the control device for activating the drive device may be designed to emit signals to the drive device, so that these divert the deflection device into periodic or random movements a middle position offset in which this deflects the radiation emitted by the radiation source optical radiation in the decoupling interface. In the method, it is preferred that, for the homogenization of the radiation to be emitted into the decoupling interface of one of the radiation sources, the deflection device is offset in periodic or statistical movements about a middle position in which it deflects the optical radiation emitted by the radiation source into the decoupling interface. This embodiment has the advantage that not necessarily further optical components need to be arranged in the beam path between the deflection device and the decoupling interface. In addition, when switching between two positions of the deflection, the deflection does not need to be slowed down to rest, so that not only a homogenization, but also a faster switching can be achieved.

The lighting device is generally suitable for lighting purposes requiring rapid variation of the color spectrum. The invention is therefore in particular also an optical device with a lighting device according to the invention. The optical device has, in addition to the illumination device, at least one further optical component which is arranged in the beam path downstream of the coupling-out interface.

Particularly preferably, the illumination device is used to examine samples. The present invention therefore also relates to an optical device for examining a sample, in particular a wide-field microscope or a fluorescence reader, with a lighting device according to the invention. Such an inspection device is characterized by the fact that it has only a few moving parts due to the design of the lighting device and is thus inexpensive and easy to produce. In addition, it can be built very compact. The lighting device is suitable for all types of microscopes. These include e.g. Universal microscopes, optical readers (including biochip readers, titer plate readers), stereo microscopes, surgical microscopes and ophthalmic devices.

In this case, the examination device can preferably be designed to carry out fluorescence investigations on a sample.

The invention will be explained in more detail below with reference to the drawings. Show it: 1 is a schematic representation of a microscope with a lighting device according to a first preferred embodiment of the invention,

2 is a schematic representation of a microscope with a lighting device according to a third preferred embodiment of the invention, and

Fig. 3 is a schematic representation of a lighting device according to another preferred embodiment of the invention.

In FIG. 1, a microscope 1, in the example a wide field fluorescence microscope, with a lighting device 2 for the examination of a sample 3 is used.

The microscope 1, which is only shown very schematically, is designed in a conventional manner and in particular has a coupling-in optical system 4, via which optical radiation for illuminating the sample 3 can be coupled into the illumination beam path of the microscope 1. Through the optical axis 5 of the coupling optics 4 and their entrance surface, a coupling-in interface of the microscope 1 is formed which at the same time also forms a decoupling interface of the lighting device 2.

The illumination device 2 comprises several, in the example four, radiation sources 6 for emitting optical radiation in respective different wavelength ranges in outgoing beam sources 6 partial beam paths, respectively arranged in the partial beam paths after the radiation sources 6 Kollirhationseinrichtungen 7 and 8 and excitation bandpass filter and a arranged in the intersection of the partial beam paths deflection 9 with a deflecting element in the form of a mirror 10 rotatable about an axis for deflecting the incident on the deflector 9 radiation of the radiation sources 6, and a drive means 11 for rotating the deflector 9 about the axis 10. In a common Strahiengangabschnitt after the deflector 9 is a focussing optics 12 is arranged, the optical radiation deflected by the deflecting device 8 focussed in a homogenizing device 13, from which the optical radiation in the Auskoppelschnittstelle tr Itt, which is given by the exit surface of the homogenizer 13 and the optical axis of the optics 12 and the homogenizer 13.

For controlling the radiation sources 6 and the drive device 11 is a control device 14th In this exemplary embodiment, the radiation sources 6 are semiconductor radiation sources, more precisely light-emitting diodes for emitting optical radiation in respectively different wavelength ranges or with different characteristic emission wavelengths, ie in each case different color, in the example red, green, blue or ultraviolet. The characteristic emission wavelength of the respective emission spectrum of one of the semiconductor radiation sources in this exemplary embodiment, as well as in the following exemplary embodiments, is the wavelength with the maximum emission intensity. In another variant, it is also possible to use the centroid wavelength, ie the mean value of the emission wavelengths weighted with the emission intensity, as the characteristic emission wavelength. The LEDs 6 therefore emit, expressed in terms of the color of the characteristic emission wavelength, optical radiation in spectrums of decreasing characteristic wavelength, ie clockwise in Fig. 1 the first LED in the red, the second LED in the green, the third LED in the blue and the fourth LED in the ultraviolet. The light-emitting diodes are chosen so that the emission spectra are well suited to excite at least four predefined fluorescent dyes distributed over the optical spectrum from the UV to the red light.

The radiation sources 6 are arranged on a in Fig. 1 indicated by a dashed line circle or arc and thus in a plane defined by the arc.

In each case one of the collimation devices 7 is arranged in the partial beam path of each of the semiconductor radiation sources 6 and collimates the optical radiation emitted by the respective semiconductor radiation source 6. In the example, aspheric lenses of high numerical aperture, preferably greater than 0.5, are used as collimation devices, which have better collimation properties compared with spherical lenses which can also be used in principle. The collimation devices 7 and the optics 12 are further designed and arranged such that the largest possible proportion of the optical radiation emitted by each of the semiconductor radiation sources 6 is coupled into the homogenization device 13. In particular, the collimation devices 7 and the optics 12 are designed in the common beam path section in front of the homogenizing device 13 so that the light conductance values are optimally matched to one another.

The trained as interference filter, only optional excitation bandpass filter 8 have each adapted to the emission spectra of the semiconductor radiation sources 6 transmission bands that narrow the spectral width of the emission spectra of the semiconductor radiation sources 6 and thus prevent crosstalk in various simultaneous fluorescence studies for different fluorescent dyes. The deflection device 9, which comprises only a mirror as deflecting element in this exemplary embodiment, is fastened to the shaft or shaft 11 oriented orthogonally to the plane in which the radiation sources 6 are arranged and can be rotated or pivoted by rotation of the shaft 11. The shaft 10 and the deflecting device 9 are arranged in the overlapping region of the partial beam paths behind the radiation sources 6, that in appropriate angular positions of the deflecting device 9 or for appropriate rotation angle of the shaft 10, each optical radiation of one of the radiation sources 6 deflected to the optics 12 can be.

The optical system 12 couples the optical radiation impinging on it into the homogenizing device 13 in the form of a mirrored hollow rod, which is aligned with its longitudinal axis parallel to the optical axis of the optical system 12.

This results in this embodiment, an alignment of the axis or shaft 10 orthogonal to the optical axis of the optics 12 and the homogenizer 13 and thus given by the decoupling interface mean radiation direction.

For rotation of the deflecting device 9, the drive device 11 is provided, which for this purpose has a controllable by electrical control signals in its position, not shown in the figures, electromagnetic actuator.

The control device 14 is for driving the radiation sources 6 independently of one another and for driving the drive means 11 and thus the setting of the deflection device 9 is formed, so that a preferred first embodiment of a method according to the invention can be performed.

For this purpose, the control device 14 has a user interface (not shown in the figures) via which a user can determine the sequence of the wavelength ranges to be set for the optical radiation to be emitted by the illumination device, its desired intensity and the respective duration of the emission. For this purpose, corresponding data can either be read in or the user has the option of selecting one from a predetermined number of combinations. In other embodiments, the order, the intensities and the radiation durations may also be fixed. In further embodiments, the duty cycle of the respective radiation source and / or the on and / or off timing may be controlled and / or synchronized by at least one signal from an external device connected to the controller 14 via at least one sync or trigger signal connection. Furthermore, the control device 14 has a user interface, by means of which adjustment inputs can be detected. These inputs are used to adjust the angular position of the deflection or the shaft 11 for each of the radiation sources 6 by electrical signals so that an at least approximately optimal coupling of the deflected optical radiation in the optics 12 and the homogenizer 13 and thus the decoupling interface is possible. A user enters for this purpose in an adjustment mode of the control device 14 for each of the radiation sources 6 separately adjustment signals in the control device 14, to which this turns by delivering corresponding control signals by means of the drive means 11, the deflection device 9. If an optimum position of the deflecting device 9 for a selected radiation source 6 is achieved, at least approximately with respect to the coupling of the optical radiation, the corresponding position of the shaft 11 is stored in the control device 14 in the form of appropriate control data associated with the radiation source. Upon selection of one of the radiation sources 6 for illumination, these data are then used to control the drive device 11.

In accordance with the predetermined sequence, intensity and duration of the radiation output in the selected predetermined wavelength ranges, the control device 14 switches on the respective radiation source 6 and shuts off, as far as this is still the case, radiation sources still in operation, so that optical radiation is only switched on - Th emitted radiation source, is collimated by the corresponding collimation 7 and then spectrally filtered by the corresponding excitation bandpass filter 8.

The control device 14 synchronously or synchronized to the output of the signals for the radiation sources 6 setting signals to the drive device 11 so that it turns the deflecting device 9 in the selected, the switched radiation source 6 corresponding angular position in which the deflection device 9 the collimated and filtered optical radiation incident thereon from the selected switched-on radiation source 6 is directed in a direction parallel to the optical axis of the focusing optic 12 onto the focusing optic 12, which couples the deflected radiation into the homogenizer 13.

Preferably, the radiation source 6 is first turned on and thus the desired radiation output is started after the deflecting device 9 has been rotated into the angular position corresponding to the selected radiation source 6 and the radiation sources 6 are switched off during one rotation of the deflecting device 9 into one of the angular positions.

After the radiation has been homogenized by means of the homogenizing device 13, it is then discharged through or into the decoupling interface. In this case, the intensity of the optical radiation can be adjusted by appropriate activation of the radiation sources 6 for each selected wavelength range or each switched radiation source separately, ie, regardless of the choice of the intensities of the delivered in other wavelength ranges optical radiation, be adjusted by appropriate signals of the controller 14.

The duration of the emission of optical radiation or the frequency with which the wavelength ranges can be changed can, depending on the activation and selection of the actuator, be in the range of milliseconds.

A second preferred embodiment differs from the first exemplary embodiment in that the control device is designed to modulate the intensity of the emitted radiation on a time scale of microseconds during the emission of optical radiation by one of the radiation sources by corresponding control of the radiation source, which is particularly is possible by the use of light-emitting diodes as radiation sources without the use of mechanical fasteners.

A third preferred embodiment of the illumination device illustrated in FIG. 2 differs from the first embodiment only in that only two radiation sources in the form of light-emitting diodes are used, which are arranged on a circular arc in a plane orthogonal to the optical axis of FIG Optics 12 and the homogenization device 13 and thus the decoupling interface are arranged. The control device 14 is designed to control only the two radiation sources. On the other hand, the axis or shaft 10 is now arranged parallel to the optical axis of the optics 12 and the homogenizing device 13 and thus the decoupling interface. Otherwise, the arrangement corresponds to the arrangement in Fig. 1 and the same reference numerals are used and the comments on the first embodiment also apply here. For the sake of clarity, the optional excitation band filters 8 are not shown in FIG. 2.

Another embodiment differs from the first embodiment in that the optic 12 and the homogenizer 13 are absent. Instead of homogenizing the optical radiation of the radiation sources to be coupled into the decoupling interface, the deflecting device is hereby set in periodic movements about a mean angular position for the currently switched radiation source, for example the angular position determined in the above-described adjustment, in which it emits the radiation emitted by the radiation source optical radiation deflects into the decoupling interface. For this purpose, the control device 14 is designed accordingly. As drive means, a galvanometer drive is preferably used. As a result of the periodic movement of the radiation beam transversely to the direction of propagation, a homogenization of the intensity distribution in the decoupling interface can take place as a function of time. Other preferred embodiments differ from the previously described embodiments in that the deflection device has a prism or a diffractive element, for example a blazed grating, instead of the mirror as deflecting element.

In yet another embodiment, the radiation sources include fiber optic elements whose radiating surfaces are arranged like the light emitting diodes in the previous examples.

In Fig. 3 is very schematically a further preferred embodiment of a lighting device shown as a scheme.

In contrast to the preceding exemplary embodiments, here several decoupling interfaces 15 are provided, by means of which an optical multiplexer 16, for example given by the drive device 11 with the shaft 10 and the deflection device 9 of the preceding embodiments in conjunction with a modified control device 14 ", is provided Radiation of one of the radiation sources 6, which are provided for the emission of optical radiation as in the first embodiment, can be dispensed in. In this example, more than four radiation sources 6 are provided, but the number can be arbitrarily greater than 1.

The only differences from the first exemplary embodiment here are that optics 12 and a homogenizing device 13 are provided for each of the coupling-out interfaces 15, not shown in FIG. 3, and that the control device 14 'is modified relative to the control device 14, that for each decoupling interface now a corresponding number of angular positions of the deflecting device 9 is stored, which are used in accordance with the currently switched on or be turned on radiation source when using the respective decoupling interface for adjusting the deflecting device 9.

Claims

claims

1. Lighting device for emitting optical radiation through at least one Auskoppelschnittstelle with at least two radiation sources (6) for emitting optical radiation in each different wavelength ranges, at least one about a predetermined axis (10) relative to the radiation sources (6) rotatable or pivotable optical Deflection device (9) for deflecting the emitted optical radiation and a drive device (11) for rotation or pivoting of the deflecting device (9) about the axis (10), wherein the radiation sources (6) so relative to the deflecting device (9) and the axis (10) are arranged so that from each of the radiation sources (6) emitted optical radiation can be deflected by the in a suitable angular position about the axis (10) rotated or pivoted deflection device (9) in the decoupling interface.

2. Lighting device according to claim 1, wherein the radiation sources comprise at least one radiation source whose radiation is emitted via a fiber optic on the deflection device (9).

3. Lighting device according to claim 1 or 2, wherein the radiation sources comprise at least one laser

4. Lighting device according to one of claims 1 to 3, wherein the radiation sources (6) comprise at least one semiconductor radiation source.

5. Lighting device according to claim 1, wherein the radiation sources (6) are arranged in a plane.

6. Lighting device according to claim 1 or 2, wherein the radiation sources (6) are arranged on a circular arc.

7. Lighting device according to one of claims 1 to 6, wherein the deflecting device (9) as deflection element comprises a mirror, a prism or a diffractive element.

8. Lighting device according to one of claims 1 to 7, further comprising a control device (14, 14 ') for controlling the drive means (11) to move the deflecting device (9) in at least two positions, in which each of these optical radiation divert the other of the radiation sources (6) into the decoupling interface.

9. Lighting device according to one of claims 1 to 8, which has a control device (14, 14 ') for controlling the radiation sources (6).

10. Lighting device according to one of claims 1 to 9, wherein the control device (14; 14 ') is designed so that it synchronously or synchronized one of the radiation sources (6) turns on and by delivering signals to the drive means (11), the deflection device (9) rotates or pivots in a position in which deflects this optical radiation of the switched radiation source (6) on the decoupling interface.

Lighting device according to one of claims 1 to 10, wherein the control device (14; 14 ') is designed and connected to the radiation sources (6) such that by means of the control device (14; 14') the intensity and / or emission duration of the from the radiation sources (6) emitted optical radiation for at least two of the radiation sources (6) is separated from each other adjustable.

12. Lighting device according to one of claims 1 to 11, wherein the control device (14; 14 ') is formed so that the position of the deflecting device (9) for the deflection of the optical radiation of one of the radiation sources (6) on the decoupling interface electronically adjustable is.

13. Lighting device according to one of the preceding claims, wherein in the beam path between the deflection device (9) and the Auskoppelschnittstelle a homogenization device (13) is arranged.

14. Lighting device according to one of the preceding claims, in which a control device (14, 14 ') for activating the drive device (11) is designed for the homogenization of the radiation to be emitted by the decoupling interface of at least one of the radiation sources (6), signals to the drive device (11). 11), so that the latter deflects the deflection device (9) into periodic or statistical movements about a middle position in which it deflects the optical radiation emitted by the radiation source (6) into the coupling-out interface.

15. An optical device with a lighting device (3) according to any one of the preceding claims.

16. The apparatus of claim 15, which is designed for the examination of a sample (1), in particular wide-field microscope or fluorescence reader.

17. A method for the sequential provision of optical radiation in at least two different wavelength ranges in a predetermined time change through at least one decoupling interface, in particular using a lighting device according to one of the preceding claims, wherein with at least two radiation sources (6), each of which optical radiation in another of the wavelength ranges, optical radiation is generated in one of the wavelength ranges and directed to an optical deflector (9), and the optical deflector (9) is rotated or pivoted relative to the radiation sources (6) that in the given temporal change optical radiation of the different wavelength ranges is deflected into the decoupling interface.

18. The method according to claim 17, wherein at least one of the radiation sources, a radiation source is used, the radiation is emitted via a fiber optic on the deflection.

A method according to claim 17 or 18, wherein a laser is used as at least one of the radiation sources.

20. The method according to any one of claims 17 to 19, wherein at least one of the radiation sources (6), a semiconductor radiation source is used.

21. The method of claim any one of claims 17 to 20, wherein synchronously or synchronized to change the wavelength ranges of the radiation sources (6) is turned on and the deflection device (9) is rotated or pivoted to a position in which this optical radiation of the switched Radiation source (6) deflects into the decoupling interface.

22. The method according to any one of claims 17 to 21, wherein the intensity and / or radiation duration of the radiation sources (6) emitted optical radiation for at least two of the radiation sources (6) is set separately from each other.

23. The method according to any one of claims 17 to 22 in which the radiation to be emitted is homogenized before reaching the decoupling interface.

24. The method according to any one of claims 17 to 23, wherein for homogenizing the radiation to be emitted into the Auskoppelschnittstelle one of the radiation sources (6), the deflection device (9) is offset in periodic or statistical movements about a middle position in which these from the Radiation source (6) deflected optical radiation in the decoupling interface.