Illumination device, in particular for a medical imaging device such as an endoscope, exoscope and / or microscope

Abstract

The invention relates to an illumination device (10a-g), in particular for an imaging device (11a), comprising: an illumination unit (14a-g) which is intended for illumination and has a first illumination source (16a-g) and at least a second illumination source (18a-g); an illumination output (20a-g) which has an optical interface and is intended for providing output illumination which is formed at least in part by the illumination; a first optical path (24a-g) from the first illumination source (16a-g) to the illumination output (20a-g) and at least a second optical path (26a-g) from the second illumination source (18a-g) to the illumination output (20a-g), the first optical path (24a-g) and the second optical path (26a-g) each having exactly three optical beam former elements (28a-g, 30a-g, 32a-g, 34a-g), preferably lenses.

Description

[0001] Illumination device, in particular for a medical imaging device such as an endoscope, exoscope and / or microscope

[0002] The present invention relates to a lighting device, in particular for a medical imaging device such as an endoscope, exoscope and / or microscope, and to a medical, in particular endoscopic, exoscopic and / or microscopic, imaging device comprising such a lighting device.

[0003] Imaging devices such as endoscopic or exoscopic devices that generate multispectral or hyperspectral images are known from the prior art. Multispectral or hyperspectral images have, in addition to two spatial dimensions, such as a conventional camera image, a spectral dimension. The spectral dimension encompasses several spectral bands (wavelength bands). Multispectral and hyperspectral images differ primarily in the number and width of their spectral bands.

[0004] Several imaging devices for generating such multispectral or hyperspectral images are known, particularly in the context of medical applications. For example, DE 20 2014 010 558 U1 describes a device for capturing a hyperspectral image of an examination region of a body. The device includes an input lens for generating an image in an image plane and a slit-shaped aperture in the image plane for masking out a slit-shaped region of the image. The light passing through the aperture is spread out by a dispersive element and recorded by a camera sensor. As a result, the camera sensor can record a plurality of spectra, each with an associated spatial coordinate, along the longitudinal direction of the slit-shaped aperture.The described device is further configured to record additional spectra along the longitudinal direction of the slit-shaped aperture in a direction different from the longitudinal direction of the slit-shaped aperture. The method underlying this disclosure for generating multispectral or hyperspectral images is also known as the so-called pushbroom method.

[0005] In addition to the pushbroom method, there are other methods for generating multispectral or hyperspectral images. In the so-called whiskbroom method, the examination area or object is scanned point by point, and a spectrum is obtained for each point. In contrast, the staring method acquires multiple images with the same spatial coordinates. Different spectral filters and / or illumination sources are used from image to image to resolve spectral information. Furthermore, there are methods in which a two-dimensional multicolor image is decomposed into several individual spectral images using suitable optical elements such as optical slicers, lenses, and prisms, which are simultaneously acquired on different detectors or detector areas. This is sometimes referred to as the snapshot approach.

[0006] As described in DE 10 2020 105 458 A1, multispectral and hyperspectral imaging devices are particularly suitable as endoscopic imaging devices. In this context, multispectral and / or hyperspectral imaging is a fundamental field of application, for example, for diagnostics and for assessing the success or quality of a procedure.

[0007] White light imaging is also used, particularly in medical imaging. Observed tissue is illuminated with white light, and images of the tissue are generated using a camera or other image capture sensor, which can then be displayed to a user.

[0008] Fluorescence imaging is also used, especially in medical imaging. Tissue is specifically illuminated in a specific wavelength range to excite fluorescent dye molecules introduced into specific entities, such as tissue regions. The resulting emitted light at a longer wavelength can be observed through a suitably selected filter, which can filter out the excitation light.

[0009] Multimodal imaging devices allow the acquisition of white light images, multispectral images, fluorescence images, and / or hyperspectral images. Examples of such imaging devices include multimodal endoscopes and multimodal exoscopes. To implement different modes, illumination devices may be required that can be operated in different illumination modes to generate illumination light in different spectral ranges as needed.

[0010] US 10,481,095 B2 and US 11,668,922 B2 disclose lighting devices with multiple illumination sources, the light emitted by each of which can be combined using beam splitter elements. Based on the prior art, the invention is based, in particular but not limited to, the object of providing reliable and efficient illumination of an examination area.

[0011] This object is achieved according to the invention by a lighting device and an endoscopic, exoscopic and / or microscopic imaging device as described herein and defined in the claims.

[0012] The invention relates to a lighting device, in particular for a medical imaging device such as an endoscope, exoscope and / or microscope, comprising:

[0013] - a lighting unit which is intended to provide lighting and has a first lighting source and at least one second lighting source,

[0014] - a lighting output which has an optical interface, in particular for connection to a light guide, and is intended to provide an output lighting which is at least partially formed by the lighting,

[0015] - a first optical path from the first illumination source to the illumination output

[0016] - and at least a second optical path from the second illumination source to the illumination output.

[0017] The illumination device can be part, in particular a subassembly, of a medical, in particular endoscopic, exoscopic, and / or microscopic, imaging device. The imaging device can comprise a medical imaging device such as an endoscope, exoscope, and / or microscope, which can be supplied with the output illumination via the light guide, which can also be part of the imaging device. The imaging device can be designed to provide at least a portion, preferably at least a majority, and particularly preferably substantially all of the output illumination for illuminating and / or illuminating an examination region.The imaging device and in particular the illumination device can be provided to provide light in a wavelength range from 100 nm to 1 mm, preferably from 200 nm to 1000 nm and particularly preferably from 400 nm to 1000 nm in the form of a broad, continuous spectrum or in the form of several separate partial spectra.

[0018] In some embodiments, the imaging device and in particular the imaging apparatus is configured to be insertable into a cavity for inspection and / or observation, for example, into an artificial and / or natural cavity, such as the interior of a body, a body organ, tissue, or the like. The imaging device and in particular the imaging apparatus can also be configured to be insertable into a housing, casing, shaft, pipe, or other, particularly artificial, structure for inspection and / or observation.

[0019] The imaging device and in particular the imaging apparatus can be configured to record tissue parameters, images of wounds, images of body parts, etc. For example, the imaging device can be configured to image a surgical field. The imaging device and / or the imaging apparatus can comprise a spatially and spectrally resolved image acquisition unit, which comprises at least one optical system and at least one image acquisition sensor coupled to the optical system, which is configured to perform an image acquisition of an image region, generating spatially and spectrally resolved image data that includes both spatial and spectral information.

[0020] The image acquisition unit and in particular the optics and / or the image acquisition sensors can be configured for multispectral and / or hyperspectral imaging, specifically for capturing and / or generating multispectral and / or hyperspectral image data. Multispectral imaging or multispectral image data can refer in particular to imaging in which at least two, in particular at least three, and in some cases at least five spectral bands can be and / or are captured independently of one another. Hyperspectral imaging or hyperspectral image data can refer in particular to imaging in which at least 20, at least 50, or even at least 100 spectral bands can be and / or are captured independently of one another.

[0021] In some embodiments, the imaging device and / or imaging apparatus comprises a white-light camera and / or sensor technology for white-light image acquisition. The imaging device and / or imaging apparatus can be configured for spectrally resolved imaging and white-light imaging in addition to the above. Separate optics and / or shared optics can be used for this purpose. The white-light imaging and the spectrally resolved imaging can be performed simultaneously or alternately, or at times simultaneously and at times sequentially.

[0022] In some embodiments, the imaging device and / or the imaging apparatus comprises sensors for fluorescence imaging. The imaging device and / or the imaging apparatus can be configured for spectrally resolved imaging and, optionally, for white-light imaging and fluorescence imaging. Separate optics and / or shared optics can be used for this purpose. The fluorescence imaging, optionally the white-light imaging, and the spectrally resolved imaging can be performed simultaneously or alternately, or at times simultaneously and at times sequentially.

[0023] For some applications, it may be advantageous to be able to use a high spectral resolution. In these cases, hyperspectral imaging is a suitable option. This can be combined with white-light imaging and / or fluorescence imaging. This enables real-time observation via a white-light image and / or a fluorescence image, even if the acquisition of spectrally resolved image data is essentially only real-time, meaning that, for example, several seconds are required to create a spectrally resolved image.

[0024] For some applications, it may be advantageous to generate spectral image data in real time. This includes, for example, generating a spectrally resolved image in less than one second or even multiple times per second. In this case, it may be appropriate to use multispectral imaging. A potentially lower spectral resolution is then offset by a higher frame rate. Depending on the application, it may be sufficient to consider only a few different spectral ranges and / or wavelengths, for example, two, three, or four, or generally fewer than ten.

[0025] In this case, additional white-light imaging can be omitted if desired. Spectrally resolved image data, acquired in real time or delivering multiple images per second, can also be used for surveillance purposes. It's not necessary to create a single image for a user to display; the image data can also be processed in the background.

[0026] The optical interface can be fixed or connectable and detachable. Furthermore, the optical interface can be combined with a mechanical interface, so that an optical connection is automatically established, for example, when the imaging device is mechanically connected.

[0027] The imaging device may include a controller configured to automatically coordinate an operating state of the imaging device and an illumination mode of the illumination device, in particular of the illumination unit. The controller may be configured to control the illumination device and / or the imaging device.

[0028] In addition to the first and second illumination sources, the illumination unit may comprise further illumination sources, for example a third, a fourth, and / or a fifth illumination source. The illumination unit is designed to provide optical radiation, in particular in the wavelength range from 100 nm to 1 mm, preferably in the wavelength range from 200 nm to 1000 nm, and may include infrared radiation, visible light, and UV radiation.

[0029] The optical radiation can be used to illuminate an examination area, for example with white light, and / or excitation radiation can be provided to excite a luminescent dye, preferably a fluorescent dye, such as cyanine 5.5 (Cy 5.5), indocyanine green (ICG), PPIX, pafolacianin (OTL 38), VisBlue, ViRed, NIR1 or fluorescein.

[0030] Individual illumination sources of the illumination unit can be configured to emit optical radiation within a specific wavelength range and / or a specific radiation spectrum. The illumination sources are preferably all configured to emit optical radiation in different wavelength ranges and / or with different radiation spectra, with overlaps of the radiation spectra being conceivable. The illumination sources can be configured as any radiation sources deemed appropriate by a person skilled in the art, for example, vacuum lamps, LEDs, lasers, and / or laser diodes.For example, at least one of the illumination sources could be configured to emit red light, particularly in the wavelength range from 640 nm to 780 nm, at least one of the illumination sources could be configured to emit green light, particularly in the wavelength range from 490 nm to 570 nm, and / or at least one of the illumination sources could be configured to emit blue light, particularly in the wavelength range from 430 nm to 490 nm. Furthermore, at least one of the illumination sources could be configured to emit infrared radiation, particularly in the wavelength range from 780 nm to 1 mm, and / or at least one of the illumination sources could be configured to emit UV radiation, particularly in the wavelength range from 100 nm to 380 nm.

[0031] In addition, the lighting unit can have at least one optical element for beam shaping, beam splitting and / or beam combining, and / or beam deflection. The optical element can be provided to shape radiation provided by one or more of the illumination sources, in particular to focus an optical beam, and / or to split radiation provided by one or more of the illumination sources into two beam paths or to combine two beams provided by at least two of the illumination sources and / or to deflect radiation provided by one or more of the illumination sources, in particular to thereby provide illumination for the lighting unit.

[0032] The output illumination at the lighting output consists at least partially of the illumination provided by the lighting unit and may additionally include components of further illumination from another lighting unit of the lighting device. The lighting device may optionally have a homogenizer upstream of the lighting output for homogenizing the output illumination.

[0033] An "optical path" can be understood here as a unit defined by optical elements, for example for beam shaping, beam splitting and / or combining, and / or beam deflection, and optical path lengths along a beam path, and which extends along the beam path between one of the illumination sources and the illumination output. The optical elements can be part of the corresponding optical path. The first optical path and the second optical path can partially overlap, so that an optical element of the first optical path can also be part of the second optical path.

[0034] In one aspect of the invention, which can be considered on its own but also in combination with further aspects of the invention, the first optical path and the second optical path can each have exactly three optical beam shaping elements, preferably lenses.

[0035] The features according to the invention make it possible to provide reliable and efficient illumination of an examination area. In particular, advantageous operation in different modes can be enabled. A high degree of efficiency and / or operating reliability and simplicity can be achieved. The proposed combination of imaging modes or the illumination sources used for this purpose can reduce the complexity of the light source and / or image capture. A small number of installed illumination sources, filters, and / or associated optical elements can be achieved while simultaneously achieving a wide range of functions. Furthermore, installation space can be saved, thereby achieving a high degree of compactness.The use of exactly three optical beam-shaping elements in the optical paths allows for a particularly advantageous adjustment of imaging properties and thus of illumination properties of different illumination sources. Furthermore, by automatically adjusting the operating state of the imaging device and the illumination mode, a high degree of user comfort can be achieved and operating errors can be avoided. This makes it possible to provide a multimodal system that can be easily switched between different modes.

[0036] An "optical beam-shaping element" can be understood as an optical element intended for beam shaping, in particular for beam bundling or beam expansion. Examples of possible optical beam-shaping elements include diffractive optical elements, achromatic lenses, and / or individual lenses, particularly preferably converging lenses. In the case of optical beam-shaping elements that are based on the interaction of several optical sub-elements, for example, several lenses of an achromatic lens, these sub-elements are not to be counted individually as optical beam-shaping elements, but merely collectively as a single optical beam-shaping element. Beam splitter elements are not to be understood as optical beam-shaping elements.

[0037] Particularly preferably, the precisely three optical beam-shaping elements are designed as a condenser lens or a condenser, a compensator lens, in particular a converging lens, and a focus lens. Condenser lenses or condensers can generally be provided to reduce the divergence of a respectively assigned illumination source and / or to introduce as large a portion as possible of the radiation provided by the assigned illumination source into an imaging beam path and / or to at least partially collimate the provided radiation. Condenser lenses or condensers can generally ensure uniform illumination. Compensator lenses can generally be provided to compensate for an expanding beam path and to narrow it again, in particular to collimate or focus it.In this case, several lenses, in particular convex lenses, which interact in a condenser lens or a condenser are not to be counted individually, but the combination of these lenses in the form of a condenser lens or a condenser represents a single optical beam-shaping element. The same applies to a compensator lens.

[0038] If objects are named, in particular, using numerical terms such as "first," "second," "third," etc., these serve to name and / or assign objects. Thus, for example, a first object and a third object may be included, but not a second object. "Intended" should be understood as specifically designed and / or programmed, not merely as mere suitability.

[0039] In some embodiments of the invention, all optical paths from the illumination sources of the illumination unit to the illumination output can each have a maximum of, and preferably exactly, three optical beam-shaping elements, preferably lenses. This allows for a small number of installed elements while simultaneously providing a wide range of functions. Furthermore, installation space can be saved, thereby achieving a high degree of compactness. The use of a maximum of three optical beam-shaping elements in the optical paths can particularly advantageously enable the alignment of imaging properties of different illumination sources.

[0040] In a further embodiment, the first optical path and / or the second optical path can have at least two beam splitter elements arranged optically directly one behind the other, which can advantageously simplify an optical design. In particular, the adaptation of imaging properties with respect to different illumination sources can be simplified. In some embodiments, a beam splitter element can be designed as a cross-beam splitter, which comprises two individual beam splitters arranged at an angle, preferably perpendicular, to one another. One of the beam splitter elements or both beam splitter elements can be provided to combine at least two beam paths and preferably direct them in the direction of the illumination output. One of the beams can be transmitted through the beam splitter element, and the other beam can be reflected by the beam splitter element.The transmission and reflection properties of the beam splitter element can preferably be matched to the spectra of the two beams to advantageously avoid radiation losses. The beam splitter elements and individual beam splitters described herein can be designed as any optical elements deemed appropriate by a person skilled in the art, preferably comprising at least one semi-transparent mirror and / or at least one interference mirror or filter, preferably at least one dichroic mirror and / or filter.

[0041] The beam splitter elements or individual beam splitters described herein may comprise bandpass filters, in particular notch filters, so that they each have a high reflectance and a low transmittance in a narrow spectral band or bands, but otherwise a high transmittance and a low reflectance, or vice versa. Alternatively or additionally, the beam splitter elements or individual beam splitters may comprise edge filters, so that they have a high reflectance and a low transmittance in a spectral band up to an edge, but otherwise a high transmittance and a low reflectance, or vice versa.The spectral position and / or width of the corresponding notch and / or the spectral position of the edge can be adapted to the spectral range of the respective associated illumination source or sources, so that its or their light can be largely redirected, but light from other illumination sources can be largely transmitted.

[0042] In an optical beam path emanating from the illumination sources, the beam splitter elements can be arranged either before or after the compensator lens. It would also be conceivable for one of the beam splitter elements to be arranged before the compensator lens and the other after the compensator lens. Overall, the first optical path and / or the second optical path could comprise three or four beam splitter elements. One of the beam splitter elements could be configured as an output beam splitter element before the illumination output.

[0043] Advantageously, the first optical path and the second optical path are of equal length, thereby avoiding deviations and potentially measurement errors that are attributable to relative spectral intensities in different spectral ranges and that can occur, for example, when an endoscope (shaft) is rotated relative to a camera unit and / or when a light guide is rotated relative to the imaging device. Due to the essentially equal light paths, largely identical intensity profiles of the relevant illumination sources can be achieved. "Equal length" is understood here and below to mean that two lengths are equal within the scope of tolerances, in particular within the scope of manufacturing and assembly tolerances, and / or that a relative deviation between the two lengths is a maximum of 1%, preferably a maximum of 0.1%, and particularly preferably a maximum of 0.01%.

[0044] In some embodiments, the first optical path and the second optical path can have the same optical beam shaping elements, preferably lenses. This can enable identical imaging properties and / or light intensities for the different optical paths. In this case, the first optical path and the second optical path can also partially have the same optical beam shaping elements, which are part of both the first and the second optical path. Preferably, the first optical path and the second optical path have condenser lenses or condensers of the same type. In some embodiments of the invention, the first optical path and the second optical path can be identical to one another. “Identical” optical paths can be understood here as optical paths which are of equal length and which have the same, possibly partially the same, in particular jointly used, optical elements.This ensures identical imaging properties for both optical paths, which can particularly advantageously increase imaging quality.

[0045] In one development of the invention, the first optical path preferably has a first condenser lens or a first condenser, the second optical path preferably has a second condenser lens or a second condenser, and the first optical path and the second optical path preferably have a common compensator lens. This can advantageously simplify a design. By using certain optical elements together, tolerance influences can also be minimized, whereby largely identical imaging properties can be achieved for different illumination sources in a particularly advantageous manner. The first condenser lens is preferably of the same type as the second condenser lens, or the first condenser is of the same type as the second condenser. The first optical path and the second optical path can have a common focus lens, wherein the common focus lens can be arranged in front of the illumination output.Viewed in the beam direction, the common compensator lens can be arranged between the first condenser lens or the first condenser or the second condenser lens or the second condenser and the common focus lens.

[0046] In a preferred embodiment of the invention, the illumination device can have a third optical path from a third illumination source of the illumination unit to the illumination output, wherein the third optical path can have a third condenser lens or a third condenser and a dedicated compensator lens. This can advantageously increase flexibility, in particular with regard to space utilization. Furthermore, space requirements can be reduced if necessary, in particular by appropriately deflecting a beam path. The third optical path can partially overlap with the first optical path and / or the second optical path, such that an optical element of the third optical path can also be part of the first optical path and / or the second optical path. The third condenser lens can be of the same type as or a different type than the first and / or second condenser lens.Accordingly, the third condenser can be of the same type or different from the first and / or second condenser. The third optical path and the first optical path and / or the second optical path can have a common focus lens, in particular the aforementioned common focus lens, wherein the common focus lens can be arranged in front of the illumination output. Viewed in the beam direction, the dedicated compensator lens can be arranged between the third condenser lens or the third condenser and the common focus lens.

[0047] In some embodiments of the invention, the first optical path, the second optical path, and the third optical path, and particularly preferably all optical paths from illumination sources of the illumination unit to the illumination output, can be identical to one another. This ensures identical imaging properties for the three optical paths, and particularly preferably for all optical paths from illumination sources of the illumination unit to the illumination output, which can particularly advantageously improve imaging quality. Preferably, the first illumination source, the second illumination source, and the third illumination source are jointly provided to provide white light, which can particularly advantageously improve a white-light image.

[0048] In another variant of the invention, only one of the first, second, or third illumination sources is provided for providing white light, for example, as a white-light LED, while the other two of the first, second, or third illumination sources emit radiation in a narrow band, i.e., a narrow wavelength range. The white-light illumination source is therefore part of the first illumination unit, in particular together with two narrow-band illumination sources. In this way, a white-light source can be combined with narrow-band illumination sources in one illumination unit for exciting fluorescence or for use in a multispectral mode.

[0049] In particular, one of the narrowband illumination sources can have a mean wavelength in the near infrared (NIR), for example, at approximately 940 nm. The other narrowband illumination source can have a mean wavelength in the visible spectrum, for example, in the red color range, for example, at approximately 680 nm. Other mean wavelengths are also conceivable. Such a combination of two narrowband illumination sources is particularly suitable for multispectral imaging.

[0050] Advantageously, the first illumination source, the second illumination source, and / or the third illumination source are provided for simultaneous illumination, in particular white light illumination, and / or joint evaluation. This can particularly advantageously increase imaging and evaluation quality. The controller can be configured to operate the first illumination source, the second illumination source, and / or the third illumination source simultaneously in at least one operating mode and / or to simultaneously use spectral signals from a wavelength range of the first illumination source, the second illumination source, and / or the third illumination source within the scope of an analysis and / or calculation.

[0051] In one aspect of the invention, which can be considered on its own but also in combination with other aspects of the invention, the lighting device can additionally comprise the following:

[0052] - a further lighting unit, which can be provided for providing further lighting and can have at least one further first lighting source, and

[0053] - a further first optical path from the further first illumination source to the illumination output.

[0054] The illumination output can be provided to provide output illumination, which can be formed at least partially by the illumination and / or the additional illumination. The first optical path, the second optical path, and the additional first optical path can have a common output beam splitter element, in particular the aforementioned output beam splitter element, which can be provided to combine part of the illumination and part of the additional illumination to form the output illumination. The output beam splitter element can be the last beam splitter element in the beam direction, upstream of the illumination output.

[0055] The features according to the invention make it possible to provide reliable and efficient illumination of an examination area. In particular, advantageous operation in different modes can be enabled. A high degree of efficiency and / or operating reliability and simplicity can be achieved. The proposed combination of imaging modes or the illumination sources used for this purpose can reduce the complexity of the light source and / or image capture. A small number of installed illumination sources, filters, and / or associated optical elements can be achieved while simultaneously achieving a wide range of functions. Furthermore, installation space can be saved, thereby achieving a high degree of compactness.By using two illumination units combined via an output beam splitter element, design flexibility, particularly with regard to space utilization, can be significantly increased. Furthermore, the total number of available illumination sources can be increased, allowing, for example, up to nine (or more) illumination sources to be provided. Furthermore, by automatically coordinating the operating state of the imaging device and the illumination mode, a high degree of user comfort can be achieved and operating errors can be avoided. This allows for a multimodal system that can be easily switched between different modes.

[0056] In addition to the further first illumination source, the further illumination unit can have further illumination sources, for example a further second, further third or further fourth illumination source. The further illumination unit is intended to provide optical radiation, in particular in the wavelength range from 100 nm to 1 mm, preferably in the wavelength range from 200 nm to 1000 nm, and can comprise infrared radiation, visible light and UV radiation. The optical radiation can be used to illuminate an examination region, preferably with white light, and / or excitation radiation can be provided to excite a luminescent dye, preferably a fluorescent dye, such as cyanine 5.5 (Cy 5.5), indocyanine green (ICG), pafolacianine (OTL 38), VisBlue, ViRed, NIR1 or fluorescein.

[0057] Individual additional illumination sources of the additional illumination unit can be configured to emit optical radiation within a specific wavelength range and / or a specific radiation spectrum. The additional illumination sources are preferably all configured to emit optical radiation in different wavelength ranges and / or with different radiation spectra, with overlaps being conceivable. The additional illumination sources can be configured as any radiation sources deemed appropriate by a person skilled in the art, for example, vacuum lamps, LEDs, lasers, and / or laser diodes.For example, at least one of the additional illumination sources could be configured to emit red light, particularly in the wavelength range from 640 nm to 780 nm, at least one of the additional illumination sources could be configured to emit green light, particularly in the wavelength range from 490 nm to 570 nm, and / or at least one of the additional illumination sources could be configured to emit blue light, particularly in the wavelength range from 430 nm to 490 nm. Furthermore, at least one of the additional illumination sources could be configured to emit infrared radiation, particularly in the wavelength range from 780 nm to 1 mm, and / or at least one of the additional illumination sources could be configured to emit UV radiation, particularly in the wavelength range from 100 nm to 380 nm. The illumination sources and / or the additional illumination sources can be activated independently of one another or in groups, and in particular only temporarily and / or sequentially.The illumination unit and / or the further illumination unit can be operable in at least one multispectral mode, in which a first group of the illumination sources and / or the further illumination sources is at least temporarily activated and in which the illumination unit and / or the further illumination unit provides illumination light for multispectral imaging. Furthermore, the illumination unit and / or the further illumination unit can be operable in at least one fluorescence mode, in which a second group of the illumination sources and / or the further illumination sources is at least temporarily activated and in which the illumination unit and / or the further illumination unit provides illumination light for fluorescence imaging. The illumination sources and / or the further illumination sources can comprise at least one illumination source that is contained in both the first group and the second group.It is understood that mixed operating modes can also occur, in which the aforementioned modes can be used sequentially. For example, multispectral imaging and fluorescence imaging can be performed sequentially.

[0058] In addition, the further lighting unit can have at least one further optical element for beam shaping, beam splitting and / or beam combining and / or beam deflection. The further optical element can be provided to shape radiation provided by one or more of the further lighting sources, in particular to focus an optical beam, and / or to split radiation provided by one or more of the further lighting sources into two beam paths and / or to combine two beams provided by at least two of the further lighting sources and / or to deflect radiation provided by one or more of the further lighting sources, in particular to thereby provide the further illumination of the further lighting unit.

[0059] The output beam splitter element can be designed as any optical element deemed appropriate by a person skilled in the art, but preferably as a semi-transparent mirror and / or an interference mirror or filter, preferably as a dichroic mirror and / or filter. The output beam splitter element can be provided to combine two beam paths and direct them toward the illumination output. One of the beams is transmitted through the output beam splitter element, while the other beam is reflected by the output beam splitter element. The transmission and reflection properties of the output beam splitter element can preferably be matched to the spectra of the two beams to advantageously avoid beam losses.

[0060] The output beam splitter element may comprise an edge filter, so that it has a high reflectance and a low transmittance in a spectral band up to an edge, but otherwise a high transmittance and a low reflectance, or vice versa. Alternatively or additionally, the output beam splitter element may comprise a bandpass filter, in particular a notch filter, so that it has a high reflectance and a low transmittance in a narrow spectral band or narrow spectral bands, but otherwise a high transmittance and a low reflectance, or vice versa.The spectral position and / or width of the corresponding notch and / or the spectral position of the edge can be adapted to the spectral range of the illumination sources and the additional illumination sources, so that light from the illumination sources is largely reflected and light from the additional illumination sources is largely transmitted, or vice versa. Emitted wavelengths from the illumination sources can be spectrally separated from emitted wavelengths from the additional illumination sources, so that they can be separated using the edge filter.

[0061] In some embodiments, the further first optical path can have exactly two or exactly three optical beam-shaping elements, preferably lenses, thereby achieving a small number of installed optical elements while simultaneously achieving a wide range of functions. Furthermore, installation space can be saved, thereby achieving a high degree of compactness. The use of exactly two or exactly three optical beam-shaping elements in the optical path can particularly advantageously enable the imaging properties of different illumination sources to be matched. Particularly preferably, the exactly two or exactly three optical beam-shaping elements are designed as a condenser lens or a condenser and a focus lens and possibly additionally a compensator lens, in particular a converging lens. The focus lens can be designed as the aforementioned common focus lens.

[0062] In further embodiments of the invention, the illumination device can comprise a further second optical path from the further second illumination source to the illumination output, wherein the further second optical path can have exactly two or exactly three optical beam-shaping elements, preferably lenses. This makes it possible to achieve a small number of installed optical elements while simultaneously providing a wide range of functions. Furthermore, installation space can be saved, whereby a high degree of compactness can be achieved. The use of exactly two or exactly three optical beam-shaping elements in the optical path can particularly advantageously enable the imaging properties of different illumination sources to be matched.Particularly preferably, the precisely two or precisely three optical beam-shaping elements are designed as a condenser lens or a condenser and a focus lens, and possibly additionally a compensator lens, in particular a converging lens. The focus lens can be designed as the aforementioned common focus lens.

[0063] The further first optical path and the further second optical path can be of equal length, thereby avoiding deviations and, if applicable, measurement errors that are due to relative spectral intensities in different spectral ranges and can occur, for example, when an endoscope (shaft) is rotated relative to a camera unit and / or when a light guide is rotated relative to the imaging device. Due to the essentially equal light paths, largely identical intensity profiles of the affected additional illumination sources can be achieved.

[0064] In some embodiments of the invention, the further first optical path and the further second optical path can have the same optical beam-shaping elements, preferably lenses. This enables identical imaging properties for the various further optical paths. The further first optical path and the further second optical path can also partially have the same optical beam-shaping elements, which are part of both the further first and the further second optical paths. Preferably, the further first optical path and the further second optical path have condenser lenses or condensers of the same type.

[0065] In certain embodiments of the invention, an optical path from the respective (further) illumination source to the illumination output can be identical for all (further) illumination sources of the illumination unit and the further illumination unit. This ensures identical imaging properties for all optical paths of the illumination device, which can particularly advantageously improve the imaging and illumination quality.

[0066] In one aspect of the invention, which can be considered on its own but also in combination with further aspects of the invention, the first optical path and / or the second optical path and / or the further first optical path and / or the further second optical path can have at least one beam deflection element for purely deflecting a beam path. This can advantageously increase flexibility with regard to design, in particular with regard to the arrangement of components, the use of installation space and / or cooling. The beam deflection element can be designed as any desired optical element that appears appropriate to a person skilled in the art, for example as a light guide and / or preferably as a mirror.

[0067] In one aspect of the invention, which can be considered on its own but also in combination with further aspects of the invention, the illumination device can comprise a detector unit for determining at least one illumination property of the output illumination. This can advantageously improve the imaging, illumination, and / or evaluation quality. In particular, thermal influences on the illumination spectrum or the illumination spectra due to heating and / or aging of illumination sources and / or optical elements can be taken into account and / or compensated for. This can improve white balance and / or correct an initial white balance.The detector unit can comprise at least any optical detector deemed appropriate by a person skilled in the art, for example, a photodiode, a phototransistor, a photoresistor, a CCD sensor, a CMOS sensor, and / or a camera. The illumination device can be connected to the imaging device, in particular the image capture unit, whereby feedback from the imaging device can be provided to the illumination device, in particular for white balance.

[0068] The illumination property could be an illumination spectrum, an illumination intensity, and / or an illumination power. Preferably, the illumination property is the total radiant power of the output illumination, which allows imaging, illumination, and / or evaluation quality to be particularly easily improved, while thermal influences can be easily considered and / or compensated for. In particular, white balance can be particularly easily improved and / or corrected.

[0069] In some embodiments of the invention, the output beam splitter element

[0070] - either be designed to allow a large part of the intensity of the illumination to pass in the direction of the illumination output and to redirect a portion of the intensity of the illumination in the direction of the detection unit, and to redirect a large part of the intensity of the further illumination in the direction of the illumination output and to allow a further portion of the intensity of the further illumination to pass in the direction of the detection unit,

[0071] - or be designed to redirect a large part of the intensity of the illumination in the direction of the illumination output and to allow a portion of the intensity of the illumination to pass in the direction of the detection unit, as well as to allow a large part of the intensity of the further illumination to pass in the direction of the illumination output and to redirect a further portion of the intensity of the further illumination in the direction of the detection unit.

[0072] This ensures an advantageously high illumination intensity. In particular, the portion used for a measurement can be advantageously kept low. The portion or additional portion is a maximum of 5%, preferably a maximum of 1%, and particularly preferably a maximum of 0.5% of the intensity of the illumination or additional illumination.

[0073] The devices, units, and systems according to the invention are not intended to be limited to the application and embodiment described above. In particular, to fulfill a functionality described herein, they may comprise a number of individual elements, components, and units that differs from the number stated herein. Furthermore, within the ranges of values ​​specified in this disclosure, values ​​within the stated limits are also to be considered disclosed and can be used arbitrarily.

[0074] The present invention is described below by way of example with reference to the accompanying figures. The drawings, the description, and the claims contain numerous features in combination. Those skilled in the art will expediently consider the features individually and use them in meaningful combination within the scope of the claims.

[0075] If more than one example of a particular object exists, only one of them is provided with a reference symbol in the figures and description. The description of this example can be applied accordingly to the other examples of the object. Shown are:

[0076] Fig. 1 shows a medical imaging device with an imaging device in the form of an endoscope and with a lighting device connected to the endoscope,

[0077] Fig. 2 is a schematic representation of the lighting device,

[0078] Fig. 3 is a schematic representation of a beam path of a lighting unit of the lighting device,

[0079] Fig. 4 an explanatory diagram of the beam path,

[0080] Fig. 5 is a schematic representation of a beam path of a lighting unit of a lighting device in a slightly modified variant,

[0081] Fig. 6 is a schematic representation of a lighting device in a further embodiment,

[0082] Fig. 7 is a schematic representation of a lighting device in an alternative embodiment,

[0083] Fig. 8 is a schematic representation of a lighting device in a further embodiment,

[0084] Fig. 9 is a schematic representation of a lighting device in an alternative embodiment and

[0085] Fig. 10 is a schematic representation of a lighting device in a further alternative embodiment.

[0086] Fig. 1 shows a schematic representation of a medical imaging device 12a. In the exemplary case shown, the imaging device 12a is an endoscopic medical imaging device. Alternatively, the medical imaging device 12a could be an exoscopic, microscopic, or macroscopic medical imaging device. The imaging device 12a is intended, for example, for examining a cavity 86a.

[0087] The imaging device 12a comprises a medical imaging device 11a. In the illustrated case, this is an endoscope that can be partially inserted into the cavity 86a.

[0088] The imaging device 12a comprises an illumination device 10a with an optical interface 21a. The imaging device 11a can be optically connected to the optical interface 21a. The optical interface 21a can be part of an optical-mechanical interface that can be selectively connected and detachable. The imaging device 11a can be selectively decoupled from the illumination device 10a.

[0089] The illumination device 10a is provided for providing output illumination at an illumination output 20a, which has the optical interface 21a. The output illumination can be fed to the imaging device 11a via a light guide 22a of the imaging device 12a. The imaging device 11a couples the output illumination to an object to be imaged, such as a site.

[0090] In the illustrated case, the imaging device 12a further comprises a display unit 88a, on which images based on image data acquired by the imaging device 11a can be displayed. These can be video images, still images, overlays of different images, partial images, image sequences, etc.

[0091] The imaging device 12a is multimodal. By way of example, the imaging device can be operated in three basic modes: a multispectral mode, a fluorescence mode, and a white light mode. Furthermore, it can be provided that the imaging device 12a can be operated in a hyperspectral mode in addition to or alternatively to the multispectral mode. The illumination device 10a is multimodal. The illumination device 10a can be operated in different illumination modes, in which it provides light for different imaging modes. In the present case, the illumination device 10a can be operated in three basic modes: a multispectral mode, a fluorescence mode, and a white light mode. Likewise, the imaging device 11a can be operated in different operating modes, specifically also in at least one multispectral mode, one fluorescence mode, and one white light mode.In the corresponding operating mode of the imaging device 12a, the modes of the illumination device 10a and / or the imaging device 11a are coordinated with one another.

[0092] Fig. 2 shows a schematic representation of the lighting device 10a. The lighting device 10a comprises a lighting unit 14a, which is provided for providing illumination. The lighting device 10a has a further lighting unit 60a, which is provided for providing additional illumination.

[0093] The illumination device 10a has an output beam splitter element 66a, which is provided to combine a part of the illumination and a part of the further illumination to form the output illumination.

[0094] The lighting device 10a comprises a detector unit 80a for determining at least one lighting property of the output lighting, namely its total radiant power.

[0095] The output beam splitter element 66a is provided to allow a large part of the intensity of the illumination of the illumination unit 14a to pass in the direction of the illumination output 20a and to redirect a proportion of a maximum of 1% of the intensity of the illumination of the illumination unit 14a in the direction of the detection unit 80a, as well as to redirect a large part of the intensity of the further illumination of the further illumination unit 60a in the direction of the illumination output 20a and to allow a further proportion of a maximum of 1% of the intensity of the further illumination of the further illumination unit 60a to pass in the direction of the detection unit 80a.

[0096] For this purpose, the output beam splitter element 66a has a bandpass filter which has a high transmittance and a low reflectance in one wavelength range of the illumination of the illumination unit 14a and which has a high reflectance and a low transmittance in a further wavelength range of the further illumination of the further illumination unit 60a. The bandpass filter can have a high transmittance and a low reflectance everywhere in the wavelength space except for the narrow further wavelength range, but a high reflectance and a low transmittance in the further wavelength range. The illumination device 10a has a focus lens 84a behind the output beam splitter element 66a in the direction of the illumination output 20a. The output illumination supplied to the illumination output 20a is focused by means of the focus lens 84a.The illumination device 10a may additionally comprise a homogenizer 82a, for example in the form of a homogenizer rod, for homogenizing the output illumination in front of the illumination output 20a, but this is not required.

[0097] The lighting unit 14a has a first illumination source 16a, a second illumination source 18a, a third illumination source 36a, and a fourth illumination source 38a. Alternatively, the lighting unit 14a could also have more or fewer illumination sources 16a, 18a, 36a, 38a, but at least two.

[0098] The first illumination source 16a is designed as an LED. The first illumination source 16a is designed to emit narrowband light with a mean wavelength of 550 nm.

[0099] The second illumination source 18a is designed as an LED. The second illumination source 18a is designed to emit narrowband light with a mean wavelength of 450 nm.

[0100] The third illumination source 36a is designed as an LED. The third illumination source 36a is designed to emit narrowband infrared radiation with a mean wavelength of 940 nm.

[0101] The fourth illumination source 38a is designed as an LED. The fourth illumination source 38a is designed to emit narrowband light with a mean wavelength of 660 nm.

[0102] The further lighting unit 60a has a further first illumination source 62a. Alternatively, the further lighting unit 60a could also have a further second illumination source or even further illumination sources.

[0103] The further first illumination source 62a is designed as a laser diode or alternatively as an LED. The further first illumination source 62a is provided for emitting narrowband light with a mean wavelength of 770 nm. The illumination sources 16a, 18a, 36a, 38a and the further first illumination source 62a can be activated independently of one another or in groups to implement the different operating modes. The first illumination source 16a, the second illumination source 18a, and the fourth illumination source 38a are jointly provided for emitting white light in the white light mode and / or in the multispectral mode. The third illumination source 36a and / or the further first illumination source 62a is provided for emitting excitation radiation for exciting a fluorescent dye in at least one fluorescence mode and / or in the multispectral mode.

[0104] In alternative embodiments, other mean wavelengths and / or bandwidths and / or spectra for the illumination sources 16a, 18a, 36a, 38a and the further first illumination source 62a would also be conceivable.

[0105] For example, the first illumination source 16a may be provided for emitting narrowband light with a mean wavelength of 940 nm.

[0106] The second illumination source 18a may be provided for emitting narrowband light with a mean wavelength of 450 nm.

[0107] The third illumination source 36a may be provided for emitting narrowband light with a mean wavelength of 680 nm.

[0108] The fourth illumination source 38a may be provided for emitting white light and may be a white light LED.

[0109] The fourth illumination source 38a then generates the white light in white light mode and / or in one of the other operating modes. The first, second, and / or third illumination sources (16a, 18a, 36a) then generate narrowband excitation light in multispectral or fluorescence mode.

[0110] The illumination device 10a has an optical path 24a, 26a, 54a, 90a for each illumination source 16a, 18a, 36a, 38a of the illumination unit 14a, which extends from the respective illumination source 16a, 18a, 36a, 38a to the illumination output 20a. A first optical path 24a extends from the first illumination source 16a to the illumination output 20a and comprises exactly three optical beam-shaping elements 28a, 32a, 34a.

[0111] A second optical path 26a extends from the second illumination source 18a to the illumination output 20a and comprises exactly three optical beam shaping elements 30a, 32a, 34a.

[0112] A third optical path 54a extends from the third illumination source 36a to the illumination output 20a and comprises exactly three optical beam shaping elements 34a, 40a, 42a.

[0113] A fourth optical path 90a extends from the fourth illumination source 38a to the illumination output 20a and comprises exactly three optical beam shaping elements 32a, 34a, 92a.

[0114] Thus, all optical paths 24a, 26a, 54a, 90a from the illumination sources 16a, 18a, 36a, 38a of the illumination unit 14a to the illumination output 20a each comprise exactly three optical beam shaping elements 28a, 30a, 32a, 34a, 40a, 42a, 92a.

[0115] The optical beam-shaping elements 28a, 30a, 40a, 92a are designed as condenser lenses 48a, 50a, 56a, 94a, namely a first condenser lens 48a spaced by a distance L1 from the first illumination source 16a, a second condenser lens 50a spaced by a distance L1 from the second illumination source 18a, a third condenser lens 56a spaced by a distance L1' from the third illumination source 36a, and a fourth condenser lens 94a spaced by a distance L1 from the fourth illumination source 38a. The first condenser lens 48a, the second condenser lens 50a, and the fourth condenser lens 94a are identical to one another. The third condenser lens 56 differs from the first condenser lens 48a, the second condenser lens 50a and the fourth condenser lens 94a, also with respect to a distance L1 ' to the associated illumination source 36a.In alternative embodiments, L1 ' = L1 could apply and the third condenser lens 56a could be designed identically to the other condenser lenses 48a, 50a, 94a.

[0116] The optical beamformer element 32a is configured as a common compensator lens 52a, which is common to the first optical path 24a, the second optical path 26a, and the fourth optical path 90a. The optical beamformer element 42a is configured as a dedicated compensator lens 58a, which is solely part of the third optical path 54a.

[0117] The optical beam shaping element 34a is designed as the focus lens 84a and is common to all optical paths 24a, 26a, 54a, 90a.

[0118] The illumination device 10a has three beam splitter elements 44a, 46a, 98a, each of which is provided to couple one of the illumination sources 18a, 36a, 38a of the illumination unit 14a into a beam path emanating from the illumination source 16a in the direction of the illumination output 20a.

[0119] The beam splitter element 44a is part of the first optical path 24a and the second optical path 26a. The beam splitter element 44a is spaced a distance L2 from the first condenser lens 48a and the second condenser lens 50a, respectively. The beam splitter element 44a has an edge filter with an edge that lies in the wavelength space between a wavelength range emitted by the first illumination source 16a and a wavelength range emitted by the second illumination source 18a, for example, at 500 nm.

[0120] The beam splitter element 46a is part of the first optical path 24a, the second optical path 26a, and the third optical path 54a. The beam splitter element 46a is spaced a distance L4 from the fourth condenser lens 94a. The beam splitter element 46a has an edge filter with an edge that lies in the wavelength space between a wavelength range emitted by the first illumination source 16a and the second illumination source 18a and a wavelength range emitted by the fourth illumination source 38a, for example, at 600 nm.

[0121] The beam splitter element 98a is part of the first optical path 24a, the second optical path 26a, the third optical path 54a, and the fourth optical path 90a. The beam splitter element 46a has an edge filter with an edge that lies in the wavelength space between a wavelength range emitted by the first illumination source 16a, the second illumination source 18a, and the fourth illumination source 38a and a wavelength range emitted by the third illumination source 36a, for example, at 800 nm. The beam splitter elements 44a, 46a are optically arranged directly one behind the other and spaced apart by a distance L3. The common compensator lens 52a is arranged optically between the beam splitter element 46a and the beam splitter element 98a.

[0122] The output beam splitter element 66a and, if applicable, the homogenizer 82a are part of the first optical path 24a, the second optical path 26a, the third optical path 54a, and the fourth optical path 90a. The beam splitter element 98a and the output beam splitter element 66a are arranged optically directly one behind the other.

[0123] The first optical path 24a, the second optical path 26a and the fourth optical path 90a are of equal length, since the following relationship applies between the distances L2, L3 and L4:

[0124] L4 = L2 + L3

[0125] The first optical path 24a, the second optical path 26a, and the fourth optical path 90a also have the same optical beamforming elements 28a, 30a, 32a, 34a, and 92a. The first optical path 24a, the second optical path 26a, and the fourth optical path 90a are thus identical to one another.

[0126] The third optical path 54a differs from the first optical path 24a, the second optical path 26a, and the fourth optical path 90a. The third optical path 54a uses the dedicated compensator lens 58a instead of the common compensator lens 52a.

[0127] For each of the illumination sources 16a, 18a, 36a, 38a of the illumination unit 14a, a fundamentally similar beam path to the illumination output 20a results (except for partially different path lengths and optical components). This is sketched as an example for the first illumination source 16a in Fig. 3 and Fig. 4: The beam path for each of the illumination sources 16a, 18a, 36a, 38a always runs via the condenser lens 48a, 50a, 56a, 94a assigned to it, via a compensator lens, namely the common compensator lens 52a or the dedicated compensator lens 58a, and via the focus lens 84a.

[0128] The lighting device 10a has for each further lighting source 62a of the further

[0129] Illumination unit 60a has a further optical path 64a, in the present case only one, which extends from the respective further illumination source 62a to the illumination output 20a.

[0130] Another first optical path 64a extends from the further first illumination source 62a to the illumination output 20a and comprises exactly two optical beam shaping elements 34a, 68a.

[0131] The optical beam-shaping element 68a is configured as a condenser lens 96a, specifically as a further first condenser lens 96a associated with the further first illumination source 62a. The further first condenser lens 96a differs from the first condenser lens 48a, the second condenser lens 50a, the third condenser lens 56a, and the fourth condenser lens 94a, but could also be identical in alternative embodiments.

[0132] The optical beamforming element 34a is again designed as the focus lens 84 and is common to the optical paths 24a, 26a, 54a, 90a.

[0133] Since the further first illumination source 62a is embodied as a powerful laser diode and the further first optical path 64a is relatively short, a compensator lens can be omitted in the further first optical path 64a. The radiation losses are manageable here.

[0134] The further first optical path 64a also includes the output beam splitter element 66a and optionally the homogenizer 82a.

[0135] Further embodiments of the invention are shown in Figs. 5 to 10. The following description is essentially limited to the differences between the embodiments. With regard to structural units and components with the same reference numerals, reference can generally be made to the description of the other embodiments, in particular to the embodiment of Figs. 1 to 4. For differentiation, the reference numerals of the embodiments of Figs. 5 to 10 are followed by one of the letters "b" to "g" instead of the letter "a" of the embodiment of Figs. 1 to 4.

[0136] Fig. 5 shows a variant of a lighting device 10b which is modified compared to the previous embodiment, in which the positions of a lighting output 20b and a detector unit 80b are exchanged.Accordingly, an output beam splitter element 66b of the illumination device 10b is provided to redirect a large portion of the intensity of illumination from a lighting unit 14b of the illumination device 10b in the direction of the illumination output 20b and to allow a maximum of 1% of the intensity of the illumination from the illumination unit 14b to pass in the direction of the detection unit 80b, as well as to allow a large portion of the intensity of a further illumination from a further illumination unit 60b of the illumination device 10b to pass in the direction of the illumination output 20b and to redirect a further portion of a maximum of 1% of the intensity of the further illumination from the further illumination unit 60b in the direction of the detection unit 80b. Accordingly, the transmission and reflection properties of the output beam splitter element 66b are exactly the opposite of those in the previous embodiment.

[0137] This arrangement may allow certain requirements regarding space utilization and / or cooling to be better met.

[0138] Fig. 6 shows a further embodiment of a lighting device 10c with a total of nine lighting sources 16c, 18c, 36c, 38c and further lighting sources 62c, 72c, of which not all are provided with reference numerals in the figure for the sake of clarity.

[0139] A lighting unit 14c of the lighting device 10c has, as in the previous embodiments, four lighting sources 16c, 18c, 36c, 38c.

[0140] However, these are arranged differently than in the previous embodiments, namely such that beams from three of the illumination sources 16c, 18c, 38c are combined not by means of a single beam splitter, as in the previous embodiments in the case of the beam splitter elements 44a, 44b, but by means of a beam splitter element 44c designed as a cross beam splitter. Individual beam splitters of the cross beam splitter of the beam splitter element 44c can, with appropriate selection and arrangement of the emission regions of the illumination sources 16c, 18c, 38c, as in the previous embodiments, comprise an edge filter. Accordingly, a beam splitter element 46c can also have an edge filter.

[0141] In addition, all optical paths 24c, 26c, 54c, 90c associated with the illumination sources 16c, 18c, 36c, 38c of the illumination unit 14c are identical to one another, in particular of the same length, and have the same condenser lenses 48c, 50c, 56c, 94c, a common compensator lens 52c, and a common focus lens 84c for all of the illumination sources 16c, 18c, 36c, 38c. A dedicated compensator lens 58a, 58b, as in the previous embodiments, is not used here.

[0142] A further lighting unit 60c of the lighting device 10c now has, instead of just one, as in the previous embodiments, five further lighting sources 62c, 72c, of which only two are provided with reference numerals in Fig. 6.

[0143] The additional illumination unit 60c has two additional beam splitter elements 100c, 102c. The additional beam splitter elements 100c, 102c are optically arranged directly one behind the other. In this case, they are designed as cross beam splitters. Three beams are combined by means of the beam splitter elements 100c, 102c. The additional beam splitter element 102c combines beams from three of the additional illumination sources 62c. Beams from two of the additional illumination sources 72c are then fed to this combined beam by the additional beam splitter element 100c. Depending on the selected emission spectra of the additional illumination sources 62c, 72c, individual beam splitters of the beam splitter elements 100c, 102c designed as cross beam splitters comprise an edge filter or a bandpass filter.

[0144] All further optical paths 64c, 74c, which are assigned to the further illumination sources 62c, 72c of the further illumination unit 60c and which are not all provided with reference symbols in Fig. 6 for the sake of clarity, are identical to one another, in particular of the same length, and have for all of the further illumination sources 62c, 72c the same condenser lenses 96c, of which only one is provided with reference symbols in Fig. 6 and which are identical to the condenser lenses 48c, 50c, 56c, 94c, a common compensator lens 104c, which is identical to the common compensator lens 52c, and the common focus lens 84c.

[0145] In summary, for all illumination sources 16c, 18c, 36c, 62c, 72c of the illumination unit 14c and the further illumination unit 60c, an optical path 24c, 26c, 54c, 64c, 74c from the respective illumination source 16c, 18c, 36c, 62c, 72c to the illumination output 20c is identical. The following relationship applies to the distances L2, L3, L4 shown in Fig. 6:

[0146] L2 = L3 + L4 In each of the optical paths 16c, 18c, 36c, 64c, 72c there are exactly three optical beam shaping elements 28c, 30c, 32c, 34c, 40c, 68c, 70c, 76c, 92c, namely in the form of the condenser lenses 48c, 50c, 56c, 94c, 96c, the common compensator lenses 52c, 104c and the focus lens 84c.

[0147] The nine illumination sources 16c, 18c, 36c, 38c and further illumination sources 62c, 72c can be configured, for example, as LEDs and / or laser diodes and can have any emission spectra deemed appropriate by a person skilled in the art. They can, for example, be designed to emit narrowband light with a mean wavelength of 405 nm, 450 nm, 550 nm, 660 nm, 700 nm, 770 nm, 850 nm, 940 nm, and / or 1000 nm.

[0148] If the emission spectra of the illumination sources 16c, 18c, 36c, 38c and further illumination sources 62c, 72c are selected such that the emitted wavelength ranges of the illumination sources 16c, 18c, 36c, 38c are all higher or alternatively all lower than the emitted further wavelength ranges of the further illumination sources 62c, 72c, an output beam splitter element 66c can comprise an edge filter with an edge in the wavelength space that lies between the wavelength range and the further wavelength range, instead of a bandpass filter, as in the previous embodiments.

[0149] Fig. 7 shows a further embodiment of a lighting device 10d with a total of six lighting sources 16d, 18d, 36d and further lighting sources 62d, 72d, of which not all are provided with reference numerals in the figure for the sake of clarity.

[0150] In the present case, an illumination unit 14d and a further illumination unit 60d of the illumination device 10d each have three illumination sources 16d, 18d, 36d, 62d, 72d, whose beams are combined by means of beam splitter elements 44d, 46d of the illumination unit 14d and further beam splitter elements 100d, 102d of the illumination unit 60d, designed as individual beam splitters. Cross beam splitters, as in the previous exemplary embodiment, are not used here. In other words, in the present exemplary embodiment, one illumination source 38c or another illumination source has been removed from each cross beam splitter compared to the previous one. The illumination unit 14d is provided for providing white light. A first illumination source 16d of the illumination unit 14d is designed as an LED and is provided for emitting narrowband light with a mean wavelength of 450 nm.The second illumination source 18d of the illumination unit 14d is designed as an LED and is intended to emit narrowband light with a mean wavelength of 550 nm. The third illumination source 36d of the illumination unit 14d is designed as an LED and is intended to emit narrowband light with a mean wavelength of 660 nm.

[0151] Alternatively, one of the illumination sources, and in particular the third illumination source 36d, is designed as a white light source, for example, as a white light LED. The first illumination source 16d can be designed as a narrow-band LED with a mean wavelength in the NIR (near-infrared) range of approximately 940 nm. The second illumination source 18d can be designed as a narrow-band LED with a mean wavelength of 680 nm and can be used, for example, to excite fluorescence or for multispectral imaging.

[0152] The beam splitter elements 44d, 46d comprise edge filters with a filter edge that lies between the wavelength ranges of the combined beams.

[0153] The additional illumination sources 62d, 72d of the additional illumination unit 60d can be configured, for example, as LEDs and / or laser diodes and can have any emission spectra deemed appropriate by a person skilled in the art. They can be provided, for example, for emitting narrowband light with a mean wavelength of 405 nm, 700 nm, 770 nm, 850 nm, 940 nm, and / or 1000 nm. With appropriate selection of the emission spectra of the additional illumination sources 62d, 72d and their arrangement, the additional beam splitter elements 100d, 102d can comprise edge filters with an edge lying between the wavelength ranges of the combined beams.

[0154] An output beam splitter element 66d may include an edge filter if all other wavelength ranges of the additional illumination sources 62d, 72d are above or below the wavelength ranges of the illumination sources 16d, 18d, 36d. Otherwise, a bandpass filter may also be required.

[0155] Here, too, for all illumination sources 16d, 18d, 36d, 62d, 72d of the illumination unit 14d and the further illumination unit 60d, an optical path 24d, 26d, 54d, 64d, 74d from the respective illumination source 16d, 18d, 36d, 62d, 72d to an illumination output 20d is identical, in particular of the same length. Each of the optical paths 24d, 26d, 54d, 64d, 74d also contains exactly three optical beam-shaping elements 28d, 30d, 32d, 34d, 40d, 68d, 70d, 76d.

[0156] Fig. 8 shows an embodiment of a lighting device 10e in which, compared to the further lighting unit 60d of the previous embodiment, changes have been made in that in a further lighting unit 60e of the lighting device 10e, one of the further illumination sources has been removed and a beam deflection element 78e is additionally used. The beam deflection element 78e is designed as a fully reflecting mirror.

[0157] A lighting unit 14e of the lighting device 10e is identical to the lighting unit 14d of the previous embodiment.

[0158] Here, too, for all illumination sources 16e, 18e, 36e, 62e, 72e of the illumination unit 14e and the further illumination unit 60e, an optical path 24e, 26e, 54e, 64e, 74e from the respective illumination source 16e, 18e, 36e, 62e, 72e to an illumination output 20e is identical, in particular of the same length. Each of the optical paths 24e, 26e, 54e, 64e, 74e also contains exactly three optical beam-shaping elements 28e, 30e, 32e, 34e, 40e, 68e, 70e, 76e.

[0159] By means of this arrangement and in particular a parallel arrangement of the lighting unit 14e and the further lighting unit 60e, certain requirements with regard to space utilization, in particular with regard to a spatial direction, and / or cooling can be better taken into account if necessary.

[0160] Fig. 9 shows an embodiment of a lighting device 10f in which, compared to the further lighting unit 60e of the previous embodiment, a further lighting source (without reference numeral) and a further beam splitter element 102f for feeding a beam from this further lighting source have been added to a further lighting unit 60f of the lighting device 10f. Furthermore, in contrast to the previous embodiment, a common compensator lens 104f, viewed in the beam direction to a lighting output 20f, has been arranged in front of a beam deflection element 78f. A lighting unit 14f of the lighting device 10f is identical to the lighting unit 14e of the previous embodiment.

[0161] Here, too, for all illumination sources 16f, 18f, 36f, 62f, 72f of the illumination unit 14f and the further illumination unit 60f, an optical path 24f, 26f, 54f, 64f, 74f from the respective illumination source 16f, 18f, 36f, 62f, 72f to an illumination output 20f is identical, in particular of the same length. The following relationship applies to the distances L2, L3, L4, L6, L9, L10 shown in Fig. 9:

[0162] L2 = L3 + L4

[0163] L6 = L9 + L10

[0164] In each of the optical paths 24f, 26f, 54f, 64f, 74f there are also exactly three optical beam shaping elements 28f, 30f, 32f, 34f, 40f, 68f, 70f, 76f.

[0165] By means of this arrangement and in particular a parallel arrangement of the lighting unit 14f and the further lighting unit 60f, certain requirements with regard to space utilization, in particular with regard to a spatial direction, and / or cooling can be better taken into account if necessary.

[0166] Fig. 10 shows an embodiment of a lighting device 10g in which, compared to the further lighting unit 60f of the previous embodiment, a further lighting source in a further lighting unit 60g of the lighting device 10g has been removed in order to reduce lateral installation space requirements.

[0167] A lighting unit 14g of the lighting device 10g is identical to the lighting unit 14f of the previous embodiment.

[0168] Here, too, for all illumination sources 16g, 18g, 36g, 62g, 72g of the illumination unit 14g and the further illumination unit 60g, an optical path 24g, 26g, 54g, 64g, 74g from the respective illumination source 16g, 18g, 36g, 62g, 72g to an illumination output 20g is identical, in particular of the same length. The following relationship applies to the distances L2, L3, L4, L5, L6, L9, L10, L11 shown in Fig. 10:

[0169] L2 = L3 + L4

[0170] L6 = L9 + L10 L11 = L3 + L5

[0171] In each of the optical paths 24g, 26g, 54g, 64g, 74g there are also exactly three optical beamforming elements 28g, 30g, 32g, 34g, 40g, 68g, 70g, 76g.

[0172] FE

[0173] List of reference symbols

[0174] 10 Lighting device

[0175] 11 Imaging device

[0176] 12 Imaging device

[0177] 14 Lighting unit

[0178] 16 first light source

[0179] 18 second lighting source

[0180] 20 Lighting output

[0181] 21 optical interface

[0182] 22 light guides

[0183] 24 first optical path

[0184] 26 second optical path

[0185] 28 optical beam shaping element

[0186] 30 optical beam shaping element

[0187] 32 optical beam shaping element

[0188] 34 optical beam shaping element

[0189] 36 third lighting source

[0190] 38 fourth illumination source

[0191] 40 optical beam shaping element

[0192] 42 optical beam shaping element

[0193] 44 beam splitter element

[0194] 46 beam splitter element

[0195] 48 first condenser lens

[0196] 50 second condenser lens

[0197] 52 common compensator lens

[0198] 54 third optical path

[0199] 56 third condenser lens

[0200] 58 dedicated compensator lens

[0201] 60 additional lighting units

[0202] 62 additional first lighting source

[0203] 64 further first optical path

[0204] 66 Output beam splitter element

[0205] 68 optical beam shaping element

[0206] 70 optical beam shaping element

[0207] 72 further second illumination source 74 further second optical path

[0208] 76 optical beam shaping element

[0209] 78 beam deflection element

[0210] 80 Detector unit 82 Homogenizer

[0211] 84 Focus lens

[0212] 86 Cavity

[0213] 88 display unit

[0214] 90 fourth optical path 92 optical beamforming element

[0215] 94 fourth condenser lens

[0216] 96 further first condenser lens

[0217] 98 beam splitter element

[0218] 100 additional beam splitter elements

[0219] 102 additional beam splitter element

[0220] 104 common compensator lens

Claims

Claims 1. Illumination device (10a-g), in particular for a medical imaging device (11a) such as an endoscope, exoscope and / or microscope, comprising: - a lighting unit (14a-g) which is provided for providing lighting and has a first lighting source (16a-g) and at least one second lighting source (18a-g), - a lighting output (20a-g) which has an optical interface (21 ag) and is intended to provide an output illumination which is at least partially formed by the illumination, - a first optical path (24a-g) from the first illumination source (16a-g) to the illumination output (20a-g) and - at least one second optical path (26a-g) from the second illumination source (18a-g) to the illumination output (20a-g), characterized in that the first optical path (24a-g) and the second optical path (26a-g) each have exactly three optical beam shaping elements (28a-g, 30a-g, 32a-g, 34a-g), preferably lenses.

2. Lighting device (10a-g) according to claim 1, characterized in that all optical paths (24a-g, 26a-g) from illumination sources (16a-g, 18a-g, 36a-g, 38a-c) of the illumination unit (14a-g) to the illumination output (20a-g) each have at most and preferably exactly three optical beam shaping elements (28a-g, 30a-g, 32a-g, 34a-g, 40a-g, 42a-b), preferably lenses.

3. Lighting device (10a-g) according to one of the preceding claims, characterized in that the first optical path (24a-g) and / or the second optical path (26a-g) has at least two beam splitter elements (44a-g, 46a-g) arranged optically directly one behind the other.

4. Lighting device (10a-g) according to one of the preceding claims, characterized in that the first optical path (24a-g) and the second optical path (26a-g) are of equal length.

5. Lighting device (10a-g) according to one of the preceding claims, characterized in that the first optical path (24a-g) and the second optical path (26a-g) have the same optical beam formula elements (28a-g, 30a-g, 32a-g, 34a-g), preferably lenses.

6. Lighting device (10a-g) according to one of the preceding claims, characterized in that the first optical path (24a-g) has a first condenser lens (48a-g) or a first condenser, the second optical path (26a-g) has a second condenser lens (50a-g) or a second condenser and the first optical path (24a-g) and the second optical path (26a-g) have a common compensator lens (52a-g).

7. The illumination device (10a-b) according to claim 6, characterized by a third optical path (54a-b) from a third illumination source (36a-b) of the illumination unit (14a-b) to the illumination output (20a-b), wherein the third optical path (54a-b) comprises a third condenser lens (56a-b) or a third condenser and a dedicated compensator lens (58a-b).

8. Lighting device (10a-g) according to one of the preceding claims, characterized in that the first illumination source (16a-g) and the second illumination source (18a-g) are provided for simultaneous illumination and / or joint evaluation.

9. Lighting device (10a-g) according to the preamble of claim 1 and in particular according to one of the preceding claims, characterized by - a further lighting unit (60a-g) which is provided for providing further lighting and has at least one further first lighting source (62a-g), and - a further first optical path (64a-g) from the further first illumination source (62a-g) to the illumination output (20a-g), wherein the illumination output (20a-g) is provided for providing an output illumination which is at least partially formed by the illumination and / or the further illumination, wherein the first optical path (24a-g), the second optical path (26a-g) and the further first optical path (64a-g) have a common output beam splitter element (66a-g) which is provided to combine a part of the illumination and a part of the further illumination to form the output illumination.

10. Lighting device (10a-g) according to claim 9, characterized in that the further first optical path (64a-g) has exactly two or exactly three optical beam-shaping elements (34a-g, 68a-g, 70c-g), preferably lenses.

11. Lighting device (10c-g) according to claim 9 or 10, characterized in that the further lighting unit (60c-g) has a further second lighting source (72c-g).

12. Lighting device (10c-g) according to claim 11, characterized by a further second optical path (74c-g) from the further second illumination source (72c-g) to the illumination output (20c-g), wherein the further second optical path (74c-g) has exactly two or exactly three optical beam shaping elements (34c-g, 70c-g, 76c-g), preferably lenses.

13. Lighting device (10c-g) according to claim 12, characterized in that the further first optical path (64c-g) and the further second optical path (74c-g) are of equal length.

14. Lighting device (10c-g) according to claim 12 or 13, characterized in that the further first optical path (64c-g) and the further second optical path (74c-g) have the same optical beam shaping elements (34c-g, 70c-g, 68c-g, 76c-g), preferably lenses.

15. Lighting device (10c-g) according to one of claims 9 to 14, characterized in that for all lighting sources (16c-g, 18c-g, 36c-g, 62c-g, 72c-g) of the lighting unit (14c-g) and the further lighting unit (60c-g), an optical path (24c-g, 26c-g, 54c-g, 64c-g, 74c-g) from the respective lighting source (16c-g, 18c-g, 36c-g, 62c-g, 72c-g) to the lighting output (20c-g) is identical.

16. Lighting device (10e-g) according to the preamble of claim 1 and in particular according to one of the preceding claims, characterized in that the first optical path (24a-g) and / or the second optical path (26e-g) has at least one beam deflection element (78e-g) for a pure deflection of a beam path.

17. Lighting device (10a-g) according to the preamble of claim 1 and in particular according to one of the preceding claims, characterized by a detector unit (80a-g) for determining at least one lighting property of the output lighting.

18. Lighting device (10a-g) according to claim 17, characterized in that the lighting property represents a total radiant power of the output lighting.

19. Lighting device (10a-g) according to one of the preceding claims, but at least according to claims 9 and 17, characterized in that the output beam splitter element (66a; 66c-g) is provided either to allow a large part of the intensity of the illumination to pass in the direction of the illumination output (20a; 20c-g) and to redirect a portion of the intensity of the illumination in the direction of the detection unit (80a; 80c-g) and to redirect a large part of the intensity of the further illumination in the direction of the illumination output (20a; 20c-g) and to allow a further portion of the intensity of the further illumination to pass in the direction of the detection unit (80a; 80c-g), or is provided to redirect a large part of the intensity of the illumination in the direction of the illumination output (20b) and to redirect a portion of the intensity of the To allow illumination to pass in the direction of the detection unit (80b) and to allow a large part of the intensity of the further illumination to pass in the direction of the illumination output (20b) and to redirect a further part of the intensity of the further illumination in the direction of the detection unit (80b).

20. Medical imaging device (12a), in particular endoscopic, exoscopic and / or microscopic medical imaging device (12a), with an illumination device (10a-g) according to one of the preceding claims.

Images