Illumination device and method for generating an illumination light

Abstract

The invention relates to an illumination device for generating an illumination light, comprising: an illumination light source, an optical interface for connecting an optical fiber for discharging the illumination light, a projection optical unit for projecting the illumination light source onto a projection plane, on which a coupling surface of the optical fiber can be provided, a detection device for detecting at least one property of an optical fiber connected to the optical interface, and a control unit for controlling the illumination light source on the basis of the detected property of the optical fiber. The light source has a plurality of light generating elements which can be activated in groups on the basis of the detected property of the optical fiber. The invention also relates to a method for generating an illumination light.

Description

[0001] JENOPTIK Optical Systems GmbH

[0002] LO-24-021-P-WO

[0003] 1 / 21

[0004] Lighting device and method for producing an illuminating light

[0005] Technical field

[0006] The invention relates to a lighting device with an optical interface for connecting an optical fiber.

[0007] State of the art

[0008] From CN117768022A a training method for an artificially intelligent fiber detector is known, which is intended to detect defects in an optical fiber.

[0009] CN1869751A discloses a coupling for a fiber optic connector in which a light barrier is used to detect whether an optical fiber is connected. A disadvantage is that the specification of the connected fiber cannot be determined.

[0010] From JP2000019351 A, a coupling for a fiber optic connector is known in which a light barrier is used to detect whether an optical fiber is connected. A disadvantage is that the specification of the connected fiber cannot be determined.

[0011] A device for determining the core diameter of an optical fiber is known from CN101846500A. However, this device is not suitable for integration into a light source.

[0012] From JPH10-267790 A a method for determining the core diameter of a multimodal optical fiber is known.

[0013] From JPS63-214638 A, a method for determining the core diameter of an optical fiber is known, in which a section of the fiber is bent and light is coupled into this section. The core diameter is determined from the image of the end face of the fiber. However, the fiber can be damaged when bent.

[0014] From EP1465256 A1, a lighting device with several light-emitting diodes (LEDs) is known. However, no fiber coupling is provided.

[0015] From CN202791536 U, a lighting device is known in which the light from several light-emitting diodes is coupled together into an optical fiber. A disadvantage is that light JENOPTIK Optical Systems GmbH

[0016] LO-24-021-P-WO

[0017] 2 / 21 can enter the fiber sheath or next to the fiber if a fiber with too small a core diameter is attached.

[0018] DE10245140A1 discloses a laser therapy device with a fiber optic connection, which includes an RFID system for identifying the fiber optic cable. US2011 / 0238049 A1 discloses a laser therapy device with a fiber optic connection, which includes a sensor for identifying the fiber optic cable.

[0019] EP0408160A1 discloses a surgical laser device with an optical fiber connection, which includes mechanical switches, optical switches, or barcodes for identifying the optical fiber. US2006 / 0210228 A1 discloses an optical fiber detector for identifying an optical fiber.

[0020] JENOPTIK Optical Systems GmbH

[0021] LO-24-021-P-WO

[0022] 3 / 21

[0023] Object of the invention

[0024] The object of the invention is to provide an energy-efficient, universally applicable lighting device for supplying light via an optical fiber.

[0025] Solution to the task

[0026] The problem is solved by a lighting device according to claim 1 and a method for generating an illumination light according to claim 10 and a use of a detection device according to claim 11.

[0027] Advantages of the invention

[0028] The advantage of the invention lies in avoiding the disadvantages of known arrangements. The lighting device according to the invention is universally applicable and energy-efficient. Whereas previously several different lighting devices were required depending on the application, now a single one suffices. In particular, the lighting device can be suitable for selectively connecting optical fibers with coupling surfaces of varying sizes. Furthermore, the energy consumption is adapted to the specific optical fiber being used. Thus, the sustainability of the lighting device is increased compared to known lighting devices.

[0029] Description

[0030] The following describes a lighting device according to the invention, along with the method and use according to the invention.

[0031] The lighting device serves to generate illumination. The lighting device comprises a light source. Advantageously, this can be an LED light source. This can include several light-generating elements, for example, light-emitting diodes. The light-emitting diodes can be arranged individually on a chip, in particular a semiconductor chip. However, several or all of the light-emitting diodes can also be configured as a single light-emitting area on a common chip. Several or all of the light-emitting diodes can have a wavelength conversion element. With a wavelength conversion element, it is possible, for example, to generate white LED light. The light source can also include other light-generating elements, such as laser diodes, in particular those equipped with a wavelength conversion element. JENOPTIK Optical Systems GmbH

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[0034] The main emission direction of the light-generating elements can be a z-direction. The light-generating elements can be arranged in an xy-plane. The coordinates x, y, and z can form a Cartesian coordinate system.

[0035] The light-generating elements can be Lambertian radiators. However, it is also possible that the light-generating elements each have a collimation element, in particular that these are designed as collimated light-emitting diodes, i.e., those with a restricted divergence angle of the radiation.

[0036] The lighting device also includes an optical interface for connecting an optical fiber to transmit the illumination light. The optical fibers intended for connection can be multimodal. They can have one or more fiber cores. They can be designed as step-index fibers or graded-index fibers. Glass fibers, particularly fused silica fibers, are advantageous. However, in the lower price segment, plastic fibers can also be used. Connection can be made, for example, via a detachable optical fiber connector, such as an SMA, FC / PC, or ST connector. The connector can have a locking mechanism, such as a locking sleeve or a bayonet fitting. The end of the optical fiber that connects to the optical interface can be embedded in a ferrule.The optical interface can be located, for example, on the housing of the lighting device. Optical fibers can be provided for connection to the optical interface. These fibers are designed as single fibers with a core. The core can have a round or polygonal cross-section, such as a square or hexagon. The core of the single fiber can be surrounded by a cladding layer. The cladding layer can have a lower refractive index than the core. Alternatively, an optical fiber suitable for connection can be designed as a bundle of several individual fibers, which can be arranged side by side and packed as closely as possible. This can have the advantage that the fiber bundle is mechanically more flexible.However, in an optical fiber designed as a fiber bundle, the effectiveness of light coupling may be lower than in an optical fiber which only has a single fiber of the same cross-sectional area.

[0037] The lighting device also includes a projection optic for projecting the light source onto a projection plane, in which a single-coupling surface of the optical fiber can be arranged. JENOPTIK Optical Systems GmbH

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[0040] All light-generating elements can be projected onto a nominal coupling area located in the projection plane using the projection optics. The nominal coupling area can be the coupling area of ​​a connectable nominal optical fiber with a maximum coupling area. If, however, an optical fiber with a smaller coupling area than the nominal coupling area is connected, then, as described below, those light-generating elements whose image lies within the nominal coupling area but outside the detected coupling area can be deactivated according to the detected coupling area.

[0041] The coupling area can be the area of ​​the fiber core of the optical fiber at the fiber end. More generally, and also in the case of an optical fiber configured as a fiber bundle, the coupling area can be the area at the end of the optical fiber bounded by the smallest convex envelope of all the fiber cores of the individual fibers. The coupling area can be, for example, circular or polygonal. It can be approximately circular, meaning that the circumcircular diameter is no more than 20% larger than the incircular diameter, and in particular, no more than 10% larger.

[0042] The coupling surface can, for example, be positioned at a specific location in the projection plane by connecting the optical fiber to the optical interface using a connector.

[0043] The lighting device also includes a detection device for detecting at least one property of an optical fiber connected to the optical interface.

[0044] The lighting device also includes a control unit for controlling the lighting light source depending on the detected property of the optical fiber.

[0045] The detection device can include an RFID sensor. This allows the detection of an RFID chip attached to the optical fiber, for example, at the ferrule, on which the properties of the optical fiber can be stored or encoded. This may restrict the lighting device to the use of specific optical fibers that have an RFID chip with the corresponding encoding. This technical limitation of optical fiber compatibility can have the economic advantage that fibers from other manufacturers cannot be used, as they are not encoded in a compatible manner. JENOPTIK Optical Systems GmbH

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[0048] The detection device can include a camera. The camera can be arranged such that an image of the fiber end, in particular an image of the coupling surface, can be captured. From this captured image, the properties of the optical fiber, for example, the diameter of the coupling surface, can be determined. For this purpose, known methods of pattern recognition in digital images and / or image recognition methods using artificial intelligence, which have been trained to recognize optical fiber end surfaces, can be used.

[0049] The detection device can include a photodiode. The photodiode can be arranged to detect the intensity of a back reflection from the fiber end. From the intensity of the back reflection, the diameter of the coupling area, for example, can be determined. This method can be faster and more cost-effective than camera-based methods, but may have a higher error rate.

[0050] The detection device can include a set of electrical coding contacts with which mating contacts attached to the optical fiber can be made. The coding of the contacts can be linked to the properties of the optical fiber. This may restrict the lighting device to the use of specific optical fibers which, for example, have the corresponding coding of the mating contacts at the fiber connector.

[0051] The at least one property of the optical fiber can advantageously be a diameter, an area, or a shape of the coupling surface of the optical fiber, or the numerical aperture of the optical fiber. It may also be possible to include one or more additional properties, in particular further properties of those mentioned.

[0052] The illumination light source has several light-generating elements, which are grouped into at least a first group and a second group. The control unit includes a light-generating element group selection device. This device serves to select such groups of light-generating elements based on at least one detected property, such that the light-generating elements of the selected groups can be projected with an image in the projection plane onto the coupling surface of the optical fiber. "Projectable" means that the image of the light-generating elements of the group lies at least partially, preferably predominantly, and ideally completely within the coupling surface. The light-generating element group selection device can be found at JENOPTIK Optical Systems GmbH LO-24-021-P-WO

[0053] 7 / 21 For example, with an optical fiber and a small coupling area, only the first group of light-generating elements, which are located on or near the optical axis, can be selected. With an optical fiber and a large coupling area, the light-generating element group selection device can, in addition to the first group, select a second group of light-generating elements, which are located peripherally to the first group with respect to the optical axis. It is also possible for three or more groups to be provided, with each group being located peripherally to the preceding group. The coupling area of ​​the optical fiber can, for example, have an effective diameter between 0.5 mm and 10 mm. If the coupling area is not circular, a circle with the same area as the coupling area can be assumed as the effective diameter.The light-generating element group selection device can be implemented as a computing unit which performs the selection using a stored program.

[0054] Furthermore, the control unit can have separately controllable electrical circuits for each group of light-emitting elements. The control unit can be configured to supply operating current only to the groups of light-emitting elements selected by the light-emitting element group selection device. Energy can be saved by not selecting the non-projectable groups and thus keeping them switched off. This also prevents unnecessary heat generation at the optical interface and in the optical fiber. The control unit can include a processing unit that uses a stored program to control the electrical driver circuits for the group circuits.

[0055] Advantageously, the first group of light-generating elements can have a smallest convex envelope, and the light-generating elements of the second group can lie outside the smallest convex envelope of the first group.

[0056] Advantageously, the first group can have exactly one light-generating element, or exactly three, or exactly four light-generating elements.

[0057] The light-generating elements of the second group can be arranged concentrically with an N-fold rotation axis lying in a z-direction, where N is the number of light-generating elements of the second group. JENOPTIK Optical Systems GmbH

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[0060] The lighting device can also include a detection light source, which provides detection light for the detection device. This can be advantageous if the detection device includes, for example, a camera. The detection light can be coupled into the beam path of the lighting device via a partially reflective mirror. It can also be coupled in via the camera path. The detection light source can also be arranged as a ring light or as an oblique light source near the optical interface. In this case, coupling into the beam path is unnecessary if the detection light is guided past the beam path of the illumination light. Alternatively, the detection light can be generated by the illumination light sources themselves—possibly at reduced light intensity. In this case, a separate detection light source is not required.

[0061] Another aspect of the invention is a method for generating illumination light by means of a lighting device, comprising

[0062] • Providing a lighting light source with multiple light-generating elements grouped into at least two groups,

[0063] • Connecting an optical fiber with a coupling surface to an optical interface of the lighting device,

[0064] • Providing a projection optic to image the light-generating elements onto a projection plane in which the coupling surface of the optical fiber is arranged,

[0065] • Detection of the coupling area using a detection device,

[0066] • Selecting such groups of light-generating elements whose image in the projection plane lies at least partially within the detected coupling area,

[0067] • Operate at least one of the selected group of light-generating elements to produce the illumination light,

[0068] • Projecting the illumination light onto the coupling surface of the optical fiber,

[0069] • Carrying the illumination light away from the lighting device via the optical fiber.

[0070] Another aspect of the invention is the use of a detection device for detecting the diameter of an insertion surface of an optical fiber arranged in a projection plane, which is connected to an optical interface of several light-generating elements JENOPTIK Optical Systems GmbH

[0071] LO-24-021-P-WO

[0072] 9 / 21 comprehensive lighting device is connected, and to deactivate such light-generating elements which cannot be projected onto the coupling surface.

[0073] The effective diameter can be assumed in the manner described above if the light entry surface is not circular.

[0074] All light-generating elements can be projected onto a nominal coupling area located in the projection plane. The nominal coupling area can be the coupling area of ​​a connectable optical fiber with the largest coupling area. If, however, an optical fiber with a smaller coupling area than the nominal coupling area is connected, then, according to the detected coupling area, those light-generating elements whose image lies within the nominal coupling area but not within the detected coupling area can be deactivated. Deactivation can be carried out by means of a control unit.

[0075] The purpose of using this technology can be to save energy and / or to avoid cladding-guided light modes in the optical fiber.

[0076] The figures show the following:

[0077] Fig. 1 shows a first embodiment of a lighting device with a first optical fiber in an x-projection.

[0078] Fig. 2 shows the first embodiment of the lighting device with a second optical fiber.

[0079] Fig. 3 shows a first example of an illumination light source.

[0080] Fig. 4 shows a second example of an illumination light source.

[0081] Fig. 5 shows a third example of an illumination light source.

[0082] Fig. 6 shows a fourth example of an illumination light source.

[0083] Fig. 7 shows a fifth example of an illumination light source.

[0084] Fig. 8 shows a second embodiment of a lighting device.

[0085] Fig. 9 shows an optical fiber designed as a fiber bundle.

[0086] Fig. 10 shows the coupling surface of the optical fiber designed as a fiber bundle.

[0087] Examples of implementation

[0088] The invention is explained below using exemplary embodiments. JENOPTIK Optical Systems GmbH

[0089] LO-24-021-P-WO

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[0091] Fig. 1 shows a first embodiment of a lighting device with a first optical fiber in an x-projection. The lighting device 1 serves to generate illumination 2. The lighting device comprises an illumination light source 4. The lighting device 1 also comprises an optical interface 9 for connecting an optical fiber 10 for transmitting the illumination 2. The connection can be made, for example, via an optical fiber connector, such as an SMA connector. For this purpose, the end of the optical fiber can be embedded in a ferrule 14. The optical interface 9 can, for example, be arranged on the housing of the lighting device 1.

[0092] The lighting device 1 also includes a projection optic 15 for projecting the lighting light source 4 onto a projection plane 20, in which a single-coupling surface 13 of the optical fiber 10 can be arranged. The projection optic 15 comprises a first lens group 16, which includes one or more lenses, and a second lens group 17, which also includes one or more lenses.

[0093] The lighting device also includes a detection device 21 for detecting at least one property of an optical fiber 10 connected to the optical interface 9.

[0094] The lighting device also includes a control unit 30 for controlling the lighting light source 4 depending on the detected property of the optical fiber 10.

[0095] The detection device 21 includes an RFID sensor 25. This allows an RFID chip 26 attached to the optical fiber 10, for example to the ferrule 14, to be detected, on which the property of the optical fiber 10 is stored or encoded.

[0096] At least one property of the optical fiber 10 can advantageously be a diameter, an area, or a shape of the coupling surface 13 of the optical fiber 10. It may also be possible to include one or more further properties in addition to the at least one property, in particular further properties of the aforementioned type.

[0097] In the first illustrated embodiment, the illumination light source 4 has several light-generating elements 5, which are grouped into a first group 6 and a second group 7. The control unit 30 has a light-generating element group selection function. JENOPTIK Optical Systems GmbH

[0098] LO-24-021-P-WO

[0099] 11 / 21 direction 31 for selecting such groups 6, 7 of light-generating elements 5 based on at least the recorded property, so that the light-generating elements 5 of the selected groups can be projected with an image in the projection plane 20 onto the coupling surface 13 of the optical fiber 10.

[0100] In Fig. 1, an optical fiber 10 with a fiber core 11 having a maximum fiber core diameter, for example 5 mm, is connected to the interface 9. The coupling area 13 can be the nominal coupling area, i.e., the largest provided coupling area. As can be seen from the illustrated beam path of the illumination light 2, both the first group 6 and the second group 7 of light-generating elements 5 can be projected onto the coupling area 13. Since the coupling area 13 extends sufficiently far around the optical axis in the x and y directions, respectively, the light from the peripherally located second group 7 also reaches the coupling area. Thus, both the first group 6 and the second group 7 are selected by the light-generating element group selection device 31.

[0101] Furthermore, the control unit 30 has separately controllable electrical circuits with a first LED driver 32 for the first group 6 and a second LED driver 33 for the second group 7 of light-generating elements 5. The control unit 30 supplies the groups 6 and 7 of light-generating elements 5 selected by the light-generating element group selection device 31 with an operating current via the LED drivers 32 and 33. The arrows represent the signal flows.

[0102] Fig. 2 shows the first embodiment of the lighting device with a second optical fiber. In this figure, an optical fiber 10 with a fiber core 11 having a small core diameter, for example 2 mm, is connected at the interface 9. The coupling area 13 is now smaller than the nominal coupling area from Fig. 1. As can be seen from the illustrated beam path of the illumination light 2, only the first group 6 of light-generating elements 5 can be projected onto the coupling area 13. The inactive beam path 3 of the switched-off second group 7 of light-generating elements 5, shown with dashed lines, would fall onto the ferrule 14 and could not be coupled into the core 11 of the optical fiber 10 via the coupling area 13. Thus, only the first group 6 is selected by the light-generating element group selection device 31.

[0103] The control unit 30 supplies only the first group 6 with an operating current via the circuit of the first LED driver 32. The second LED driver 33 is inactive, so the circuit of the second group 7 of light-generating elements 5 is deactivated, i.e., without JENOPTIK Optical Systems GmbH

[0104] LO-24-021-P-WO

[0105] 12 / 21

[0106] Operating current is not supplied, and therefore no light is produced. Energy can be saved by not supplying any operating current to the second, non-projectable group 7. Furthermore, unnecessary waste heat at the optical interface 9, 14 and in the optical fiber 10 can be avoided.

[0107] In a first, non-figurative embodiment of the example, the detection device 21 comprises a camera, see also the second embodiment in Fig. 8. The camera is arranged such that an image of the fiber end, in particular an image of the coupling surface, can be captured. From the captured image, the properties of the optical fiber, for example the diameter of the coupling surface, can be determined.

[0108] In a second, non-figurative variation of the example, the detection device 21 comprises a photodiode. The photodiode is arranged such that the intensity of a back reflection from the fiber end can be detected. From the intensity of the back reflection, the diameter of the coupling area, for example, can be determined.

[0109] In a third, non-figurative variation of the example, the detection device 21 comprises a set of electrical coding contacts 27. The coding of the contacts is linked to the properties of the optical fiber.

[0110] In the further exemplary embodiments, the reference numerals introduced here shall apply accordingly.

[0111] Fig. 3 shows a first example of an illumination light source. The illumination light source 4 is shown in an xy view, while the main emission direction of the light from the light-generating elements 5 is the z-direction. In this illumination light source 4, the first group 6 comprises exactly one light-generating element. The light-generating elements of the second group 7 are arranged around the first group 6.

[0112] The first group 6 of light-generating elements has a smallest convex envelope 36, which corresponds to the contour of the centrally depicted light-generating element of the first group 5, 6. The light-generating elements of the second group 7 lie outside the smallest convex envelope 36 of the first group 6. JENOPTIK Optical Systems GmbH

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[0115] Fig. 4 shows a second example of an illumination light source. In this illumination light source 4, the first group 6 comprises four light-generating elements. The light-generating elements of the second group 7 are arranged around the first group 6. The first group 6 of light-generating elements has a smallest convex envelope 36. The light-generating elements of the second group 7 lie outside the smallest convex envelope 36 of the first group 6.

[0116] Fig. 5 shows a third example of an illumination light source. In contrast to the previously mentioned example of an illumination light source, the second group 7 here additionally includes smaller light-generating elements.

[0117] Fig. 6 shows a fourth example of an illumination light source. The light-generating elements 5 of the second group 7 are arranged concentrically with an N-fold rotation axis lying in a z-direction, where N is the number of light-generating elements 5 of the second group 7. In the figure, N=10 light-generating elements 5 in the second group are shown. However, there can also be more or fewer in variations of the example.

[0118] This figure also shows the mappable area 37 for a small coupling surface, the mappable area 38 for a medium coupling surface, and the mappable area 39 for a large coupling surface. For example, the small coupling surface can have a diameter of 2 mm, the medium one 3 mm, and the large one 5 mm.

[0119] When an optical fiber with the small coupling area is connected to the lighting device, only the first group 6 is supplied with an operating current. Since the light-generating elements of the first group 6 partially protrude from the imageable area 37, this portion of the light from these light-generating elements cannot be coupled into the small optical fiber.

[0120] If an optical fiber is connected to the lighting device via the central coupling surface, only the first group 6 is supplied with operating current. Since the light-generating elements of the first group 6 are now completely within the imageable area 38, the light from these light-generating elements can be utilized more effectively.

[0121] When an optical fiber with the large coupling area is connected to the lighting device, both the first group 6 and the second group 7 are used in a JENOPTIK Optical Systems GmbH

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[0124] Operating current is applied. Since the light-generating elements of the first group 6 are now completely within the imageable area 38, the light from these light-generating elements can be better utilized.

[0125] Fig. 7 shows a fifth example of an illumination light source. The illumination light source 4 has a central light-generating element of the first group 5, 6, as well as a peripheral light-generating element of the second group 5, 7, which is ring-shaped. This can be segmented as shown, but does not have to be. Optionally, a third light-generating element of a third group 5, 8 can be provided peripherally to the second group 7.

[0126] Fig. 8 shows a second embodiment of a lighting device. Here, the lighting device 1 additionally includes a deflecting mirror 18, which deflects the illumination light 2 from the illumination light source 4. Therefore, the fiber coordinate system x'y' is rotated relative to the coordinate system xy of the illumination light source 4.

[0127] In this example, the detection device 21 comprises a camera with an image sensor 22, which is equipped with a semi-transparent camera mirror 24 and a camera lens 23. The camera 21, 22, 23, 24 is arranged such that an image of the fiber end, in particular an image of the coupling surface 13, can be captured. The properties of the optical fiber 10, for example the diameter of the coupling surface 13, can then be determined from the captured image.

[0128] For the detection device using the image sensor 22, a detection light source 28 is optionally provided to generate a detection light 29. Alternatively, the separate detection light source 28 can be omitted. Then, for example, light emitted by the illumination light source 4 can be used as the detection light.

[0129] Optionally, a second illumination source 4b can be provided, which couples a second illumination source 2b into the beam path by means of a second deflecting mirror 18b. For this purpose, if the wavelengths of the first and second illumination sources differ, the first deflecting mirror 18b can be dichroic. The second illumination source 4b can have an analogous grouping of the light-generating elements as the first illumination source 4b. In the case of the optical fiber 10 shown as an example, the beam path 3b would then also be inactive. JENOPTIK Optical Systems GmbH

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[0131] 15 / 21

[0132] The coding contacts 27 shown on the ferrule 14 are optional in the second embodiment of the lighting device.

[0133] In a first variation of the example, the detection device 21 includes, alternatively or additionally to the camera 22, 23, 24, a set of electrical coding contacts 27. The coding of the contacts is linked to the property of the optical fiber 10.

[0134] In a second, non-figurative variation of the example, the detection device 21 comprises a photodiode instead of the camera 22. The photodiode is arranged such that the intensity of a back reflection from the fiber end can be detected. From the intensity of the back reflection, the diameter of the coupling surface 13, for example, can be determined.

[0135] Fig. 9 shows an optical fiber configured as a fiber bundle. The optical fiber 10 is shown in the projection plane. The optical fiber 10 comprises several individual fibers, each with a fiber core 11 and a fiber cladding 12. The individual fibers have a hexagonal cross-section. In a variation not shown, they can have a circular cross-section. The individual fibers are embedded in a ferrule 14 at the end of the optical fiber that is located in the projection plane.

[0136] The first and second embodiments of the lighting device described above

[0137] Instead of the optical fibers shown, I can also be operated with optical fibers designed as fiber bundles.

[0138] Fig. 10 shows the coupling surface of the optical fiber configured as a fiber bundle. As already described, the coupling surface 13 is defined by the smallest convex envelope of the fiber cores.

[0139] II of the individual fibers. This figure also shows that an optical fiber implemented as a fiber bundle can be less efficient than an optical fiber with only one fiber core of the same coupling area. The sum of the areas of the individual fiber cores 11 of a fiber bundle is smaller than the coupling area 13. The light that does not strike one of the individual fiber cores 11 within the coupling area cannot be used. For clarity, the fiber jackets of the individual fibers are not shown in this figure.

[0140] Please note that the figures are not to scale. JENOPTIK Optical Systems GmbH

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[0143] The reference symbols used uniformly in all figures are as follows:

[0144] 1. Lighting device

[0145] 2. Lighting

[0146] 3. Inactive beam path

[0147] 4. Light source

[0148] 5. Light-generating element

[0149] 6. First group

[0150] 7. Second group

[0151] 8. Third Group

[0152] 9. Optical interface

[0153] 10. Optical fiber

[0154] 11. Fiber core

[0155] 12. Fiber sheath

[0156] 13. Coupling area

[0157] 14. Ferrule

[0158] 15. Projection optics

[0159] 16. First lens group

[0160] 17. Second lens group

[0161] 18. Deflection mirror

[0162] 19. Optical axis

[0163] 20. Image plane

[0164] 21. Detection device

[0165] 22. Image sensor

[0166] 23. Camera lens

[0167] 24. Camera mirror

[0168] 25. Fiber type detector

[0169] 26. RFID Element

[0170] 27. Coding contact

[0171] 28. Detection light source

[0172] 29. Detection light

[0173] 30. Control unit

[0174] 31. Computing unit, light-generating element group selection device

[0175] 32. First LED driver

[0176] 33. Second LED driver JENOPTIK Optical Systems GmbH

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[0179] 34. Projection optics

[0180] 35. Optical axis

[0181] 36. Smallest convex envelope of the first group

[0182] 37. Imaging area for a small fiber core 38. Imaging area for a medium fiber core

[0183] 39. Mapping area for a large fiber core

Claims

JENOPTIK Optical Systems GmbH LO-24-021-P-WO 18 / 21 Patent claims:

1. Lighting device (1) for producing an illumination light (2), comprising: • A light source (4), • An optical interface (9) for connecting an optical fiber (10) for conveying the illumination light (2), • A projection optic (15) for projecting the illumination light source (4) onto a projection plane (20) in which a single coupling surface (13) of the optical fiber (10) can be arranged, • a detection device (21) for detecting at least one property of an optical fiber (10) connected to the optical interface (9), • a control unit (30) for controlling the illumination light source (4) depending on the detected property of the optical fiber (10), wherein • the illumination light source (4) has several light-generating elements (5) which are grouped into at least a first group (6) and a second group (7) and • the control unit (30) has a light-generating element group selection device (31) for selecting such groups (6, 7, 8) of light-generating elements (5) based on at least the detected property, so that the light-generating elements (5) of the selected groups can be projected with an image in the projection plane (20) onto the coupling surface (13) of the optical fiber (10), and • the control unit (30) has separately controllable electrical circuits (32, 33) for each of the group (6, 7, 8) of light-generating elements (5), and the control unit (30) is designed to supply an operating current only to the groups (6, 7, 8) of light-generating elements (5) selected by the light-generating element group selection device (31).

2. Lighting device (1) according to claim 1, wherein the detection device (21) comprises at least one RFID sensor (25) and / or a camera (22, 23) and / or a photodiode and / or a set of electrical coding contacts (27). JENOPTIK Optical Systems GmbH LO-24-021-P-WO 19 / 21 3. Lighting device (1) according to one of the preceding claims, wherein at least one property of the optical fiber (10) is a diameter or an area or a shape of the coupling surface (13) of the optical fiber (10) or the numerical aperture of the optical fiber (10).

4. Lighting device (1) according to one of the preceding claims, wherein the lighting light source (4) has several light generating elements (5) which are designed as Lambertian emitters which each have collimation optics to reduce divergence.

5. Lighting device (1) according to one of the preceding claims, which is provided for connecting an optical fiber (10) designed as a fiber bundle of several individual fibers to the optical interface (9).

6. Lighting device (1) according to one of the preceding claims, wherein the first group (6) of light-generating elements (5) has a smallest convex envelope and the light-generating elements (5) of the second group (7) are located outside the smallest convex envelope of the first group (6).

7. Lighting device (1) according to one of the preceding claims, wherein the first group (6) comprises exactly one light-generating element (5) or exactly three or exactly four light-generating elements (5).

8. Lighting device (1) according to one of the preceding claims, wherein the light-generating elements (5) of the second group (7) are arranged concentrically with an N-fold axis of rotation lying in a z-direction, wherein N is the number of light-generating elements (5) of the second group (7).

9. Method for generating an illumination light (2) by means of a lighting device (1), comprising • Providing a lighting light source (4) with several light-generating elements (5) which are grouped into at least two groups (6, 7, 8), • Connecting an optical fiber (10) with a coupling surface (13) to an optical interface (9) of the lighting device (1), JENOPTIK Optical Systems GmbH LO-24-021-P-WO 20 / 21 • Providing a projection optic (15, 16, 17) for imaging the light-generating elements (5) into a projection plane (20) in which the single-coupling surface (13) of the optical fiber (10) is arranged, • Detection of the coupling area (13) by means of a detection device (21, 22, 23, 25, 26), • Selections of such groups (6, 7, 8) of light-generating elements (5) whose image in the projection plane (20) lies at least partially within the detected coupling area (13), • Operating at least one of the selected group (6, 7, 8) of light-generating elements (5) to generate the illumination light (2), • Projecting the illumination light (2) onto the coupling surface (13) of the optical fiber (10), • Discharge of the illumination light (2) from the illumination device (1) via the optical fiber (10).

10. Use of a detection device (21) for detecting the diameter of an input surface (13) of an optical fiber (10) arranged in a projection plane (20), which is connected to an optical interface (9) of a lighting device (1) comprising several light-generating elements (5), and for deactivating such light-generating elements which cannot be projected onto the input surface (13).

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