Endoscope and disposable endoscope system

Abstract

To provide an endoscope and an endoscope system, in particular, a disposable endoscope and / or a disposable endoscope system.SOLUTION: An endoscope has a first component and a second component. The second component has a proximal end and a distal end coupled to the first component. A member for photographing an image, such as a camera chip or an optical fiber element, is arranged at the distal end. Within the second component, a light guide with a light guide fiber extends so as to guide light from a light source from the proximal end to the distal end and emit the light at the distal end. The light guide fiber has a diameter of at least 80 μm and has a protective cover made of a polymer-based coating and / or a polymer-based tube material, which is arranged on the outer peripheral surface at least in a partial and / or divisional manner.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates generally to endoscopes and endoscopic systems, and more particularly to single use endoscopes and / or single use endoscopic systems. [Background technology]

[0002] Diagnostic, surgical, and / or therapeutic devices, such as diagnostic, minimally invasive surgical, or therapeutic endoscopes, are known to be of rigid or flexible construction and are fully described in the literature. Nowadays, single-use endoscopes, also called "disposable endoscopes," are increasingly used, which, by preventing contamination on the basis of a single use, can increase patient safety, particularly in medical-technical examinations, treatments, and / or minimally invasive procedures. Indeed, conventional endoscopes are designed to be reusable in the medical-technical sense, i.e., to be washable, disinfectable, and especially autoclavable.

[0003] Nevertheless, in this case, due to misuse or poor design of such devices, it may occasionally occur that the required pathogen reduction is not achieved, and thus the pathogen may be transmitted to the patient during the next use, which can be prevented by using such single-use endoscopes.

[0004] Another aspect of the increasing use of disposable endoscopes is the consideration of profitability. In particular, proper and regular reconditioning after each use requires high costs for the practitioner or clinic. Furthermore, the need for expensive investments in cleaning equipment such as heat disinfectors and autoclaves and / or plasma sterilizers justifies the use of such disposable endoscopes overall.

[0005] Another advantage of such a single-use endoscope arises from the fact that it can be used portable as a "handheld" device and therefore can be used in emergency medical, military evacuation applications or in areas that are difficult to access, such as in catastrophic disasters, where regeneration means are not particularly available.

[0006] Such single-use endoscopes, or "single-use" endoscopes or "disposable endoscopes" as they are referred to in the literature, are exemplarily described in the following documents:

[0007] The document U.S. Patent Application Publication No. 3,581,738 discloses a single-use endoscope having a body made of a synthetic resin material with a generally tubular side wall forming a speculum, and a single elongated light-guiding element embedded in the side wall, wherein the element is made of a light-guiding material that is covered with a transparent material having a refractive index different from that of the light-guiding material, and wherein the body is formed from two opposing halves separated axially from the endoscope, wherein each half has an element-enclosing member.

[0008] The rigid endoscope described in US Patent Application Publication No. 4,964,710 is equipped with an objective lens system, an eyepiece lens, and an intermediate relay lens. The relay system is a hybrid system using both plastic and glass elements. The plastic element consists of an even number (N) of axially oriented lenses, each having a length on the same order as its diameter. The glass element consists of an odd number (N minus 1) of axially oriented glass flat cylinders with polished ends.

[0009] EP 1 890 173 A1 describes a method for manufacturing a light guide suitable for use in such endoscopes. In this process, multiple optical fibers are bundled together and then the fiber bundle is cut at a mouthpiece attached to the middle of the fiber bundle. In this way, the fiber bundle is separated into a first optical fiber bundle and a second optical fiber bundle. The separation surfaces of the first and second optical fiber bundles have the same characteristics and requirements, since the first and second optical fiber bundles are formed from fiber bundles obtained by bundling multiple identical optical fibers. The first optical fiber bundle is mounted in the insertion section of the endoscope, and the second optical fiber bundle is mounted in a flexible tube, thereby forming a first light guide within the insertion section of the endoscope and a second light guide within the flexible tube. This results in separable light-transmitting sections of the light guides.

[0010] Because such endoscopes are based on a one-time use, the costs of these endoscopes are significantly reduced, so that the components or structures can necessarily be manufactured at an optimized cost. One of the main components for providing images and illumination is the light guide or image guide, which is currently attached or processed in relatively laborious processing steps. Complex mechanical elements are often associated in part with optical elements such as lenses that comprise the light guide or image guide, as well as laborious processing steps such as grinding and polishing of the end faces, which make the current light guide or image guide relatively expensive.

[0011] However, on the other hand, certain optical technical requirements must also be taken into account, particularly when using endoscopes in medical technology. This requires that the light provided by the light source be delivered to the examination site as loss-free as possible, as well as providing a faithful or accurate color display of the examination site and avoiding unnecessary heat generation at the examination site. In this case, the light beam provided by the light source and its subsequent guidance to the distal end of the endoscope present a particular challenge. Endoscopic systems with particularly small diameters require, on the one hand, extremely bright light sources and, on the other hand, light guides with optimized light beams.

[0012] When using active electronic components, such as camera chips and / or lighting LEDs, further requirements must be taken into account regarding electrical insulation, electrical shielding, and the patient leakage current, which must not exceed maximum limits depending on the area of ​​use of the endoscope: for example, for cardiac use, a maximum leakage current of 10 μA is required, which corresponds to the CF type classification (see EN 60601-1, 3rd edition, Table 3).

[0013] This may further require shielding, especially of the camera chip, from scattered light from the light guide, which may otherwise have a negative effect on image quality and / or cause image artifacts.

[0014] In addition to these optotechnical and electrical requirements, attention must also be paid to the requirement for biocompatibility. Biocompatibility requires ensuring that materials are not harmful to the human body. Regulations require that medical devices that may come into contact with the human body be identified and evaluated for potential interactions and unwanted side effects. The selection of the required tests depends on the type and duration of contact with the human body. In accordance with the European Medical Device Directive MDD93 / 42 EWG (abbreviated as MDD) or the Directive (EU) 2017 / 745 of April 5, 2017 (abbreviated as MDR), a biological evaluation of a device is required whenever direct contact between a material / device and a patient occurs.

[0015] The main regulations for biological testing and evaluation of materials are DIN EN ISO 10993 and United States Pharmacopoeia Class VI (USP Class VI). Although the significantly more comprehensive ISO 10993 should have replaced USP Class VI testing, USP testing is nowadays used quite frequently, especially for the evaluation of biocompatible plastics. For this purpose, materials intended for invasive use are evaluated for their chemical composition on the one hand and for cytotoxicity testing, in which cell cultures are tested to detect potential toxic effects. The requirements for this are summarized in DIN EN ISO 10993, especially in Parts 1 and 5 (DIN EN ISO 10993-1:2010-04). In the United States, this is subject to FDA requirements. The corresponding requirements for DIN EN ISO 10993 are included in USP Class VI.

[0016] Furthermore, the fact that the well-known regeneration methods of cleaning / disinfecting with strongly alkaline solutions and sterilization by autoclave at temperatures up to 135°C and typical steam pressures of about 3 bar are not taken into account within this range is beneficial for the design of endoscopes as single-use endoscopes, which in particular also allows for the selection of less expensive materials. Only the suitability of the materials for gas sterilization methods such as ethylene oxide sterilization, as well as the compliance with the RoHS Directive and REACH regulations, are taken into account.

[0017] The applicant's own applications under document numbers DE 102019125912 and DE 102018107523 relate to different embodiments of light guides, and laser-based light sources are not mentioned.

[0018] US Pat. No. 6,398,721 relates to a surgical microscope apparatus that may include a laser diode.

[0019] US Patent Application Publication No. 20060279950 describes LEDs. Endoscopes are not mentioned, but light guides with fibers, for example, may be used.

[0020] Similarly, US Patent Application Publication No. 20060152926 describes an LED, which may also be used, for example, in an endoscope. The LED is operated in a transmissive manner.

[0021] A highly efficient light source is described in US Patent Application Publication No. 20040246744.

[0022] The optical imaging system described in US Patent Application Publication No. 20190290100 can be used in particular for fluorescence microscopy (STED microscopy).

[0023] US Patent Application Publication No. 20060069314 describes a solid state light source for an endoscope.

[0024] DE 10 2017 108 698 A1 describes an optoelectronic component.

[0025] For endoscopic systems with small diameters, e.g., a maximum total diameter of 3 mm or less, in which a camera chip is further integrated with a light guide fiber for illumination, particularly single-use endoscopes, the particularly large integration effort required for a typical fiber bundle containing several hundred individual fibers has proven to be a disadvantage. Furthermore, the amount of light emitted at the distal end of such endoscopes poses an additional challenge, since the space available for this type of fiber bundle is becoming increasingly limited. Summary of the Invention [Problem to be solved by the invention]

[0026] The object of the present invention is to at least partially overcome or at least reduce the disadvantages of the prior art and, in particular, to provide an endoscopy system having a bright light source or illumination with a sufficiently high brightness, in particular for single-use use, and an optimized and easily integrable light guide system for this purpose. [Means for solving the problem]

[0027] The problem of the present invention is solved by the subject matter of the independent claims. Particular and preferred embodiments are set out in the dependent claims and the subsequent disclosure.

[0028] The present invention therefore relates to an endoscope having a first component and a second component, the second component having a proximal end connected to the first component, preferably a detachably connected proximal end and a distal end, at the distal end of which an image capturing element, such as a camera chip or an optical fiber element, is arranged, and within the second component extends a light guide with at least one light guide fiber for guiding light from a light source from the proximal end to the distal end and emitting it at the distal end, as well as a supply line for preferably supplying electricity to the camera chip.

[0029] The first component may incorporate a light source, in which case the light source has at least one LED chip that emits light, and the LED chip is coupled to a proximal end of the second component that is coupled to the first component such that light emitted from the LED chip can enter at least one light guide fiber of the light guide.

[0030] However, the light source can also be accommodated in the plug-in connection as a component thereof, in which case the plug-in connection is formed by the proximal end of the second component and its light guide. In this case, the light source has at least one LED integrated, preferably fixedly integrated, in the light source, which directs its emitted light into at least one light guide fiber of the light guide.

[0031] In all cases, the at least one light guide fiber has a diameter of at least 80 μm, and in this case, the at least one light guide fiber has a protective cover made of a polymer-based coating and / or a polymer-based tubing material arranged at least partially and / or sectionally on its outer surface.

[0032] In this case, the coating and / or protective covering is generally arranged over the entire outer circumferential surface, i.e., over the entire outer circumferential surface. However, it is also conceivable that the coating and / or protective covering is arranged only partially or in sections, for example in areas that are particularly subject to mechanical abuse. It is also possible to first coat or arrange the coating and / or protective covering over the entire outer circumferential surface, but then later partially or in sections remove the coating and / or protective covering from the at least one light guide fiber again. This may be advantageous and / or necessary at the point where the fiber is to be glued or attached, i.e., for example, at the distal end toward the camera chip.

[0033] Optical fiber elements for capturing or transmitting images, also known as "image guides," consist of tens of thousands of individual fibers arranged flush with one another. Such optical fiber elements may consist of or contain glass or plastic, in particular, and may be formed as glass or plastic fibers, for example.

[0034] Such an endoscope configuration has many advantages.

[0035] That is, in this disclosure, the endoscope is divided into two components: a first component, sometimes referred to as the proximal component, may incorporate, for example, a light source having at least one light-emitting LED chip coupled to the proximal end of the second component coupled to the first component, such that light emitted from the LED chip can enter at least one light guide fiber of the light guide.

[0036] In one variant of the endoscope, the light source is an integrated component, i.e., is integrated, preferably fixedly, into the bayonet connection that forms the proximal end of the second component together with the light guide of the second component, and in this case the light source has at least one integrated, i.e., integrated, preferably fixedly, LED that directs its emitted light into at least one light guide fiber of the light guide. Such an approach is also described in the applicant's patent document DE 10 2011 119 972, where, inter alia, inexpensive fiber optic illumination means are emphasized.

[0037] In other words, in the two variants described above, each first component is configured to be connectable to or even connected to a second component, sometimes called the distal component.

[0038] Depending on the exact design and the type of components it contains, the first component may be configured, for example, as a manual component, i.e., as a component that is also used, for example, to operate and / or hold the endoscope. However, it is also possible for the first component to have components that are used to control and / or operate the endoscope, i.e., configured, for example, as a control unit and / or evaluation unit, in which case the first component may be configured as an actuation device for the endoscope.

[0039] The endoscope further includes a second component having a proximal end and a distal end, and a light guide having at least one light guide fiber extending within the second component. The light guide fiber is configured to guide light from a light source from the proximal end to the distal end and emit it at the distal end. An imaging component, such as a camera chip or optical fiber image guide, for imaging is disposed at the distal end. The second component further preferably includes a supply line for supplying electricity to the camera chip when the distal end includes the camera chip.

[0040] Such an endoscope configuration with two components (or groups) is advantageous because, in the described configuration, the first component contains relatively expensive components, such as a light source, while the second component contains relatively inexpensive components. This means that the endoscope can be divided, and in this way, for example, inexpensive components can be housed in a relatively inexpensive single-use group, while less expensive, costly components are housed in a multi-use group.

[0041] For the first time, it is now possible to provide an endoscope that combines the advantages of, for example, very valuable illumination with the advantages of an endoscope intended for single-use only. It should be noted here that the endoscope according to the present disclosure does not necessarily have to be configured as a single-use endoscope or at least partially as a single-use endoscope. Rather, this can be adapted as needed.

[0042] However, it may be advantageous if the first and second components are removably connected to one another. As long as the endoscope is at least partially designed as a single-use endoscope, the second component may be disposed of after use. However, it is also possible for the second component to be removably connected to the first component, but nevertheless intended for multiple uses, and to be subjected to specific cleaning and sterilization procedures intended for medical use after being separated from the first component.

[0043] Thus, an endoscope according to the present disclosure, which may also be called a modular endoscope, is combined on the one hand with the possibility of simplified handling, and on the other hand, if the endoscope according to the present disclosure is a disposable endoscope or an endoscope formed at least partially as a disposable endoscope, i.e., at least some components are intended for single use only, high-value illumination, such as for example illumination using a laser enabling high light intensity or illumination using high-power LEDs as light sources, is combined with the advantages of a disposable device.

[0044] The second component comprising the light guide may be, for example, rigid or flexible. The second component may generally be understood as the so-called shaft of the endoscope, whereby within the scope of the present invention, the term "shaft" refers to both an entirely rigid second component and a flexible component comprising, for example, only a flexible outer cover tube, for example, made of plastic material. While the second component is rigid, it may also be configured so that the light guide enclosed by the second component is at least partially enclosed by one or more tube sections made of metal or plastic. The exact configuration of the second component may be selected depending on the intended field of use of the endoscope.

[0045] A suitable light guide for such an endoscope system may contain, for example, tens, hundreds, or even thousands of individual fibers, where the exact number of individual fibers included in the light guide depends, for example, on the desired final diameter of the light guide and / or the diameter of the individual fibers included in the light guide. Typically, common fiber diameters are between 20 μm and 100 μm. Typical diameters are 30 μm, 50 μm, and 70 μm.

[0046] To ensure that sufficient brightness or illumination intensity is guaranteed in the inspection area, particularly for single-use endoscopes or endoscopic systems with small dimensions, it may be advantageous to use a fiber that is not too thick as the light guide fiber, which on the one hand allows for inexpensive and quick assembly and on the other hand can ensure that a high light flux reaches the distal end of the endoscope from the laser light source.

[0047] A number of up to 20, preferably up to 10, such individual fibers has proven advantageous and a good compromise between assembly effort and sufficient light beam transmission, with one fiber often being sufficient for extremely thin endoscope systems. A bundle of three or seven individual fibers offers the advantage that these individual fibers can be packed very tightly within a common sleeve. A seven-fiber arrangement offers the particular advantage that a rather circular arrangement of the individual fibers within the common sleeve can be achieved, resulting in an ideal packing density for fibers with a circular cross section. In such a seven-fiber arrangement, the individual fibers can be grouped around the camera tip or the image guide at the distal end of the endoscope, for example, to enable uniform illumination of the examined tissue. However, for the rather common square tip shape of the laser diode or light-emitting diode or transducer as the light source, it may be advantageous to use four individual fibers or an integer multiple of four such fibers. On the one hand, with a maximum possible working fiber area, i.e., the cross-sectional area of ​​the fiber that is originally light-guiding, the cavity provided for illumination can be filled with more fiber, and on the other hand, improved light injection can be achieved.

[0048] In this case, it has proven advantageous for the light guide fiber or fibers to have a diameter in the range of 100 μm to 1000 μm, preferably a maximum of 500 μm, preferably in the range of 150 μm to 400 μm. Such fibers can be assembled as individual fibers much more easily and also have a sufficiently small minimum bending radius, e.g., 1×1 mm. 2For today's endoscopes with camera chips of this size, four individual fibers, one on each side of the camera, with a diameter in the range of 200 μm to 300 μm, are considered ideal. Similarly suitable are arrangements with two or three fibers on each side of the camera, for a total of eight or twelve individual fibers, with the individual fibers having a diameter in the range of 150 μm to a maximum of 200 μm. It may also be envisioned, for example, that fibers with different diameters are used to ensure the best possible filling of the cavity between the camera chip and the enclosure, thereby achieving the highest possible luminous flux. In the case of a twelve-fiber arrangement, three fibers are arranged on each side of the camera, with the middle fiber having a diameter of approximately 250 μm, for example, and the other two fibers only having diameters of 100 μm to 150 μm.

[0049] In principle, instead of individual fibers, thin fiber bundles may be used consisting of a plurality of very thin individual fibers, particularly preferably having individual fiber diameters of less than 70 μm, particularly preferably less than 50 μm, which fiber bundles only have an extremely thin jacket holding the fiber bundle together. Such fiber bundle configurations are described in the applicant's unpublished parallel applications.

[0050] In one alternative embodiment, the light guide fiber or fibers are step-index glass fibers, preferably having a glass composition that is free of lead and / or other heavy metals, apart from unavoidable traces, and free of other critical elements such as antimony and / or arsenic and / or Cr(VI).

[0051] By fiber, within the framework of this disclosure, is meant an object whose greatest lateral dimension in one spatial direction of a Cartesian coordinate system is at least 10 times, preferably at least 50 times, larger than in the other two spatial directions perpendicular to this first spatial direction. In other words, a fiber is a very long and thin object.

[0052] By step-index glass fiber is meant, within the scope of this disclosure, a glass fiber whose refractive index changes from the inside, i.e., from the core to the outside, in the form of at least one step, and in this case the glass fiber comprises a core glass and a cladding glass, the core glass having a refractive index different from that of the cladding glass.

[0053] Glass fibers include glass. In addition to the glass material, glass fibers may also include another material, so-called glue, which at least partially surrounds the surface of the glass material. Depending on the application, a wide variety of glass materials may be used in glass fibers. In particular, glass fibers may contain single-component and / or multi-component glasses. For example, a glass fiber that is essentially a single-component glass may contain silica glass and / or may be specifically formed as a silica glass fiber. In this case, the silica glass may be doped, for example with OH ions and / or fluorine, and / or may exist as a water-rich or water-poor silica glass form, still referred to as a single-component glass, or may contain multi-component glasses, for example, multi-component silicate glasses. Furthermore, the glass may be formed as a chalcogenide glass. In this case, the term "silica glass fiber" or "silica fiber" also refers to a fiber containing doped silica glass.

[0054] Preferably, the optical fiber has a fiber core and a fiber edge or fiber cladding layer, In a preferred embodiment, the core or core layer is made of a core glass.

[0055] Preferably, the optical fiber has a fiber cladding surrounding the fiber core, which in a preferred embodiment comprises a cladding glass.

[0056] Preferably, the fiber cladding has a halogen or halide content of less than 500 ppm (m / m), more preferably less than 400 ppm (m / m), even more preferably less than 300 ppm (m / m), even more preferably less than 250 ppm (m / m), even more preferably less than 200 ppm (m / m), even more preferably less than 150 ppm (m / m), even more preferably less than 100 ppm (m / m), even more preferably less than 80 ppm (m / m), even more preferably less than 60 ppm (m / m), even more preferably less than 40 ppm (m / m), even more preferably less than 20 ppm (m / m), and even more preferably less than 10 ppm (m / m). In particularly preferred embodiments, the fiber cladding is halogen-free. The halogen may be, for example, chlorine, fluorine, bromine, and / or iodine, or anions thereof. Extremely high halogen concentrations in fiber claddings, especially during steam sterilization, can lead to the formation of corresponding halogen acids, which can reduce the durability of optical fiber products and can leak out of the optical fiber products. In particular, halogen acids can corrode materials such as the special steel used in autoclaves and endoscopes, causing undesirable rust.

[0057] Preferably, the fiber core has a halogen or halide content of less than 500 ppm (m / m), more preferably less than 400 ppm (m / m), even more preferably less than 300 ppm (m / m), even more preferably less than 250 ppm (m / m), even more preferably less than 200 ppm (m / m), even more preferably less than 150 ppm (m / m), even more preferably less than 100 ppm (m / m), even more preferably less than 80 ppm (m / m), even more preferably less than 60 ppm (m / m), even more preferably less than 40 ppm (m / m), even more preferably less than 20 ppm (m / m), and even more preferably less than 10 ppm (m / m). In a particularly preferred embodiment, the core layer or core is halogen-free. In the present invention, halogen is, for example, chlorine, fluorine, bromine, and / or iodine or anions thereof. Extremely high halogen concentrations in the fiber core, especially during steam sterilization, can lead to the formation of corresponding halogen acids, which can reduce the durability of the optical fiber product and can leak out of the optical fiber product. In particular, halogen acids can corrode materials such as the special steel of autoclaves and endoscopes, causing undesirable rust.

[0058] In a specific embodiment, the optical fiber is a quartz fiber. In one specific embodiment, the fiber cladding and / or the fiber core has an amount of SiO2, e.g., amorphous, of at least 76% by weight, more preferably at least 81% by weight, even more preferably at least 84% by weight, even more preferably at least 88% by weight, even more preferably at least 92% by weight, even more preferably at least 95% by weight, even more preferably at least 97% by weight, even more preferably at least 98% by weight. A higher amount of quartz leads to improved chemical durability and improved heat resistance. Thus, a quartz fiber is particularly meant to be a quartz glass fiber, i.e., consisting of or containing amorphous SiO2.

[0059] In one particular embodiment, the core glass has the following characteristics:

[0060] Preferably, the core glass contains at least 8 wt.%, more preferably at least 23 wt.%, even more preferably at least 24 wt.%, particularly preferably at least 25 wt.%, or even at least 26 wt.% SiO2. In one particular embodiment, the core glass even contains at least 28.3 wt.% SiO2, and very particularly preferably at least 34 wt.% SiO2. In some preferred embodiments, the core glass even contains at least 35 wt.%, even more preferably at least 42 wt.% SiO2.

[0061] Suitable core glasses of these inventions include the following components within the following composition ranges (weight percent): [Table 1]

[0062] R2O is the sum of all alkali metal oxide contents at any given time.

[0063] One or more of the following components may be included in the core glass: Cs2O, Rb2O, MgO, CaO, SrO, Gd2O3, Lu2O3, Sc2O3, Y2O3, In2O3, Ga2O3, and WO3.

[0064] The following components are preferably present in the core glass either completely or at a maximum concentration of 500 ppm each due to unavoidable impurities of the raw materials, unless otherwise specified in the text: TiO2, CeO2, Nb2O5, MoO3, Bi2O3, PbO, CdO, Tl2O, As2O3, Sb2O3, SO3, SeO2, TeO2, BeO, radioactive elements, and coloring components. TiO2 in particular is preferably omitted, since this component can cause significant absorption in the UV range. In a preferred embodiment, the component WO3 is also omitted.

[0065] The components TiO2, CeO2, Nb2O5 and / or Bi2O3 may be contained in the core glass in an amount of up to 0.5 wt. %, preferably up to 0.3 wt. %, particularly preferably up to 0.2 wt. %. In one preferred embodiment, the core glass is free of these components.

[0066] Preferably, the core glass does not contain optically active components, in particular Sm2O3, Nd2O3, Dy2O3, Pr2O3, Eu2O3, Yb2O3, Tb2O3, Er2O3, Tm2O3 and / or Ho2O3. Preferred core glasses do not contain any CeO2, since CeO2 absorbs in the UV range.

[0067] The total content of the alkaline earth metal oxides, La2O3, Ta2O5, ZrO2, and HfO2, is preferably at least 40% by weight, more preferably at least 42% by weight, even more preferably at least 50% by weight, and particularly preferably at least 55% by weight, especially for core glasses with refractive indices greater than 1.65. If the content of these components is too low, the desired refractive index usually cannot be achieved. Due to molding, it is desirable for this total value not to exceed 72% by weight.

[0068] In one particular embodiment, the clad glass has the following characteristics: it preferably has an SiO2 content of more than 60 wt. %, more preferably more than 65 wt. %, and particularly preferably at least 69 wt. The SiO2 content is preferably at most 75 wt. %, and particularly preferably at most 73 wt. The clad glass tends to be more exposed to harsh environmental influences than the core glass. A high SiO2 content results in better chemical durability. Therefore, the content of this component in the clad glass is preferably higher than in the core glass.

[0069] Preferably, the composition of the cladding glass is selected or matched to the composition of the core glass so as to minimize the difference between the linear thermal expansion coefficient of the cladding glass and the linear thermal expansion coefficient of the core glass. In general, the coefficients of thermal expansion (CTE) of the fiber core and the fiber cladding in the temperature range of 20-300°C may be the same or different. In particular, the CTEs are different. Preferably, the CTE of the cladding is smaller than the CTE of the fiber core, and typically the CTE of the cladding is at least 1.0*10 -6 / K less, but also depending on the glass, typically at least 2.5*10 -6 / K. The fiber core is typically 6.5*10 -6 ~10*10 -6 / K, and the cladding has a CTE of 4.5*10 -6 ~6*10 -6 / K, which achieves that upon cooling the fiber core contracts to a greater extent than the fiber cladding, which leads to the formation of compressive stresses in the fiber cladding that protect the fiber, which is beneficial for the mechanical load carrying capacity of the fiber, especially for the bending strength of the fiber.

[0070] The following table shows suitable compositions of cladding glasses that can be used with the core glass, including (by weight % on an oxide basis): [Table 2]

[0071] In another particular embodiment, the core glass and / or the cladding glass are chalcogenide glasses, which allow for use particularly in the infrared range. The following table shows suitable compositions, in mole percent, for the core and / or cladding chalcogenide glasses: [Table 3]

[0072] where Hal = fluorine, chlorine, bromine, and / or iodine, Hal2 and / or Hal3 = chlorine and / or bromine, and R 1 = Li, Na, K, Rb and / or Cs, and R 2 = Ag and / or Cu, M 1 = Mg, Ca, Sr and / or Ba, M 2 = Zn, Cd, Hg and / or Pb, and Ln = La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Ty, Lu, Y and Sc.

[0073] Particularly preferred are glass fibers, fiber rods, or compressed fiber rods made of core and cladding glass that are free of lead or heavy metals. Such fiber systems offer high transmission, particularly in the VIS spectral range, and, due to their relatively high transmission, exhibit high color fidelity in the blue spectral range, which is particularly important in the medical evaluation of tissue. In this case, only slight differences in the color of the tissue often determine whether a tissue change is benign or malignant. Therefore, a high CRI value for the entire system consisting of the light source, light guide, and image-providing device is important. The CRI (Color Rendering Index) is a photometric characteristic that expresses the color rendering quality of multiple light sources with the same correlated color temperature. CRI values ​​greater than 90 can be achieved with the glass fibers, fiber rods, or compressed fiber rods described above. Such fiber systems are known by the applicant under the name Schott PURAVIS®, and their construction is described in German Patents Nos. 102012100233 and 102013208838. Similar fiber systems are described in EP 2072477, which also do not contain Pb.

[0074] For use in endoscopes in particular, it is advantageous if the glass fiber, fiber rod, or compressed fiber rod is made of a glass system corresponding to a numerical aperture (NA) greater than 0.64, particularly preferably greater than 0.77, with an acceptance angle 2α of greater than 80°, particularly preferably greater than 100°, for the light to be guided. On the one hand, the light of LEDs, which usually have a very wide emission angle, can be coupled into the glass fiber or fiber rod or compressed fiber rod without complex optics at the proximal end, without increasing coupling losses. On the other hand, wide-angle illumination can be achieved at the distal end without the need for additional optics, which is particularly suitable for endoscopy. Optimal illumination in the field of view of currently common cameras (typically 120° diagonal) can be achieved if the glass fiber, fiber rod, or compressed fiber rod has an acceptance angle 2α of at least 120° or an NA of at least 0.86.

[0075] After the drawing process, the glass fibers described above usually have a largely undamaged, fire-polished surface, and it is important to protect this surface as much as possible from damage. For this purpose, before the winding process, the glass fibers are coated with a so-called glue, which protects the fibers, especially against friction between the fibers, but also, for example, when they come into contact with metal surfaces. Such glues generally consist of a wax- or sterol-based solvent and are sprayed onto the glass fibers. Details of these glues are described in the applicant's unpublished parallel application.

[0076] To further increase the mechanical stability of fibers, especially those with a relatively large diameter as described above, it has proven advantageous if one or more light guide fibers have a protective covering, at least partially and / or sectionally arranged on their outer periphery, made of a polymer-based coating or a polymer-based tubing material, for example in the form of a shrinkable tube. In this case, a higher strength of the fiber and thus a smaller bending radius can be achieved. In this way, the resulting disadvantages of thicker fibers in terms of increased stiffness and a larger minimum allowable bending radius can be significantly reduced or offset.

[0077] In one embodiment, the light guide comprises a plurality of light guide fibers, in which at least one light guide fiber, preferably a plurality of light guide fibers, particularly preferably all light guide fibers, have a protective cover made of a polymer-based coating or a polymer-based tubing material arranged at least partially and / or sectionally on their outer surface.

[0078] Advantageously, the coating comprises or consists of one or more of acrylate copolymers, polyamide copolymers, polyurethane copolymers, polyimide copolymers, epoxy copolymers, ethylene-tetrafluoroethylene copolymers, or polyxylol-based compounds, such as those based on polyparaxylol compounds, also known as coating materials under the trade name "Parylene" (also called polyxylylene-based coatings), or mixtures of these compounds. Suitable coating materials are available under the trade names or brands, such as NYLON® (polyamide), TEFZEL®, Parylene®, or PMMA (polymethyl methacrylate). These layers are typically cured by heating or UV light. Alternatively or additionally, the coating may comprise a thermoplastic elastomer, such as a thermoplastic polyester elastomer or thermoplastic copolyester elastomer, such as those commercially available under the trade name Hytrel, or silicone.

[0079] In special cases, metallic coatings, for example made of gold or aluminum, can also be used. Such conductive coatings can be advantageous, for example, when additional electric field shielding and / or potential protection is required, as is the case, for example, in cardiological applications in the heart, where CF-type classification is required.

[0080] It is particularly advantageous if such coatings are applied to one or more light guide fibers by dipping, spraying, extrusion, or deposition at low pressure immediately after the fiber is drawn. This allows for the preservation of a nearly perfect, fire-polished surface of the fiber before it comes into contact with other materials or other fibers, which could cause micro-damage that reduces the fiber's strength. Furthermore, it also provides protection against hydrolytic attack.

[0081] Typically, such layers are applied by drawing the light guide, which has just been drawn out as a fiber, through a pot equipped with a nozzle, inside which the polymer material used for the coating is present, and in this case the nozzle can also adjust, among other things, the layer thickness.

[0082] For example, polymer materials can be made to be UV-curable, or the coating can be divided into an inner and an outer coating (see, for example, the abstract in the chapter "Fiber coating" in the "Encyclopedia of Modern Optics" by D. Hewak), in which case the inner coating can be made relatively flexible (with a relatively low modulus of elasticity) and the outer coating can be made relatively hard (with a relatively high modulus of elasticity), which can be particularly advantageous for minimizing stresses when bending a fiber coated in this way. However, according to Hewak, other coatings containing metal, ceramic or carbon as coating materials are also possible in principle.

[0083] Additionally, it may be envisioned that at least one additional organic coating may be applied in addition to the first coating. Such additional coatings, also called buffers, are commonly used in quartz fibers. Possible materials for such buffers include, for example, PMMA, polyamide (NYLON), polyimide, or one or more fluorinated polymers, such as ethylene-tetrafluoroethylene copolymer (abbreviated ETFE), commercially available under the trade name TEFZEL®. Such additional coatings contribute to improved robustness with respect to bending loads. In particular, the buffer layer may comprise a thermoplastic elastomer, such as a thermoplastic polyester elastomer or a thermoplastic copolyester elastomer, such as those commercially available under the trade name Hytrel®, and / or polyvinylidene fluoride, such as those available under the trade name Kynar®, or polytetrafluoroethylene or polyurethane (such as those available under the trade name Teflon®). Such buffer layers may be applied, for example, by spraying, dipping, extrusion, and electrostatic methods.

[0084] Such a layer system may consist, for example, of a two-layer system in which first a relatively thin layer, typically 10 μm to 50 μm thick, made of, for example, an acrylate or epoxy compound, is applied to the light guide, followed by a so-called buffer layer, which may have a significantly larger thickness, in the range of 50 μm to 200 μm, made of NYLON, TEFZEL®, PMMA or polyimide, as an additional mechanical protection measure.

[0085] The layer thickness of this coating is typically in the range of 5 μm to 100 μm, preferably in the range of 10 μm to 50 μm. In certain variants, layer thicknesses of up to 200 μm may be envisaged.

[0086] For use in extremely small space situations, the first coating is already sufficient to ensure the highest possible bending strength.

[0087] It should be mentioned here that other methods are conceivable, particularly for improving the strength of the fiber. For example, by a proper heat treatment of the glass, similar to a thermal preload, a higher compressive preload can be created near the surface, which can improve the bending strength of the fiber. Chemical hardening of the fiber is also conceivable. However, in this case, an additional cladding would be necessary to achieve the optical properties of the fiber, and an additional appropriate compressive preload can be created in this additional cladding by ion exchange in molten salt or spraying with a salt layer and subsequent tempering. Similarly, electron beam or ion beam hardening may also be considered. However, all of these methods are relatively laborious. Furthermore, it is difficult to maintain the optical properties of the fiber.

[0088] In one alternative embodiment, the coating may be made light-tight, i.e. opaque or light-absorbing, for example colored, such as black or blue, which is advantageous since crosstalk to the camera chip can be reduced in this way.

[0089] In this case, an embodiment in which the light guide comprises at least one glass fiber, in particular a glass fiber containing or made of a multicomponent silicate glass, or is preferably configured as a glass fiber bundle, in particular a glass fiber containing or made of a multicomponent silicate glass, is particularly advantageous, since such glass fibers allow particularly flexible adjustment of the optical properties of the glass fiber bundle and thus of the light guide or endoscope comprising these glass fibers. Furthermore, such glass fiber-based light guides have significantly higher heat resistance than polymer optical fibers (POF). This is particularly important for achieving particularly good coupling efficiency, for example, when a thin fiber bundle consisting of or containing several glass fibers is directly contact-connected to an LED chip or is brought very close to such a chip. However, fiber bundles consisting of or containing polymer optical fibers cannot withstand such thermal loads and may result in melting of the fibers.

[0090] In one embodiment, one or more light guide fibers are fitted at their proximal ends into an entrance sleeve, which serves as a mechanical interface for the laser light source and thus allows for a defined light entrance with respect to the focal length and centering relative to the light source. In the case of one or more individual fibers, ideally three or seven individual fibers, a so-called SMA connector, which allows for a defined orientation relative to the laser light source and is used specifically for laser applications, can be provided as the entrance sleeve. So-called FC connectors are also conceivable. Again, an arrangement of seven individual fibers is particularly advantageous, since it allows for a substantially circular cross section on the one hand and a minimized gusset area between the individual fibers on the other hand. This has advantages in terms of entrance efficiency. gusset refers to the intermediate space in a bundle of several circular fibers. Another optimal fiber arrangement is achieved with 19 individual fibers, where each individual fiber is optimally sealed and arranged in two shells around a central fiber. In this case, the individual fibers are generally fixed in position using an adhesive, for example a high-temperature crosslinking two-component epoxy adhesive, or a UV-curable adhesive.

[0091] However, for the rather common square or rectangular chip shape of a laser diode or light-emitting diode or converter as a light source, it may also be advantageous to use four individual fibers or an integer multiple of 2 or 4, with which the chip surface is covered as best as possible. On the one hand, for the largest possible active fiber area, i.e., the cross-sectional area of ​​the fiber that is originally intended to guide light, the cavity provided for illumination can be filled with more fibers, and on the other hand, improved light injection can be achieved.

[0092] To increase the injection efficiency, it may be further assumed that the light guide fibers are arranged by high-temperature melting at their proximal ends. In this case, on the one hand, the gusset area may be minimized, because the high-temperature deformation process allows the individual fibers, which are circular in themselves, to be transformed into at least approximately hexagonal cross sections and thus arranged almost tightly. Furthermore, a predetermined injection cross section or focal diameter can accommodate more fibers and thus transmit a higher light flux.

[0093] Such a high-temperature fused fiber can be disposed in an entrance sleeve at the proximal end, for example. However, it is equally possible for the high-temperature fused fiber to be provided at the proximal end without a sleeve. This is particularly advantageous for configurations where efficient space utilization is required, i.e., where the cross-sectional area at the proximal end is particularly small.

[0094] In another embodiment, at least one and / or several light guide fibers and / or light guides at the distal end are deformed compared to the proximal end. That is, in one embodiment, at least one and / or several light guide fibers and / or even the light guide itself may have a cross-section at the distal end that has a different shape than at the proximal end. For example, the cross-section of the fiber and / or several fibers and / or light guides may be substantially circular at the proximal end, i.e., within the limits of measurement accuracy, but may have an elliptical or kidney-shaped cross-section at the distal end, or a cross-section defined by at least two lines with different radii of curvature and / or a cross-section formed as the difference between two circles and / or ellipses that only partially overlap each other. In particular, the cross-section may be formed as a circular segment, with the radius of curvature being infinite, i.e., linear within the limits of measurement accuracy. Such a cross-section formed as a circular segment may also be called a D-shaped or substantially D-shaped cross-section.

[0095] It is also possible for different light guide fibers to have different cross sections, in which case the cross sections may be circular, particularly at the proximal end, while one or more fibers may be elliptical and other fibers kidney-shaped at the distal end. Other cross sections are also conceivable, for example rectangular or approximately rectangular cross sections, particularly at the distal end, or even polygonal cross sections in general. In particular, in this case, cross sections formed, for example, as circle segments, allow for a high utilization of the provided cavity and thus increase the light flux or illumination intensity at the distal end of the endoscope.

[0096] Such an arrangement may be particularly advantageous for ensuring a particularly advantageous spatial arrangement of the fiber and / or fibers and / or light guide relative to the camera chip.

[0097] In general, it is possible for the at least one light guide fiber and / or the light guide fibers to have, at least in part, a cross section that has a shape that differs from circular, at least within the limits of measurement accuracy, which may be advantageous in order to enable a particularly efficient, e.g. space-saving, arrangement of the individual components within the second component of the endoscope.

[0098] This may be advantageous at the very distal end of the light guide.

[0099] Thus, in one embodiment, the at least one light guide fiber and / or the plurality of light guide fibers have, at least at the distal end of the light guide, a cross-section with a flattened shape having an aspect ratio of at least 1.5:1 and / or an elliptical cross-section and / or a kidney-shaped cross-section and / or a cross-section defined by at least two lines having different radii of curvature and / or a cross-section formed as the difference surface of two circles and / or ellipses that only partially overlap each other.

[0100] As already mentioned at the beginning, the integration of thin fiber bundles into an endoscopic camera is particularly difficult and time-consuming, and this can be significantly improved by using a small number of relatively thick light guide fibers. However, even in this case, and without being limited to the specific configuration of an endoscope that is easy to integrate, especially an endoscope with a light guide that includes a small number of relatively thick individual fibers, a problem arises: when assembling the camera and packing the fibers around the camera while the camera is held in the center of the distal housing for the camera and the fibers, the camera may shift to one side, which may result in an uneven hollow space that no longer guarantees a defined, uniform arrangement of the fibers. This may result in more fibers on one side of the camera and fewer fibers on the other side of the camera, which may lead to unbalanced illumination of the tissue to be examined. Another disadvantage is that optical fibers may emit light through the fiber cladding of the fibers, to which the side of the camera is sensitive or receptive. This can result in poor-quality images, e.g., extremely low contrast, and image artifacts. Traditionally, this problem can be solved by painting or pouring a non-transparent paint or opaque epoxy onto the camera walls to reduce the penetration of scattered light, and / or by gluing the fiber and camera into the distal casing or device shaft with a non-transparent adhesive. However, the use of an opaque adhesive precludes the use of UV- or light-curing adhesives for quick installation. In some cases, the relatively low heat resistance of the camera chip precludes the use of heat-curing adhesives. Therefore, adhesives with long curing times that cure at room temperature are typically used, which can result in additional camera misalignment during the curing period, further contributing to the camera misalignment within the distal casing or shaft. Furthermore, this often results in the light guide fibers being positioned at an angle, i.e., oriented non-parallel to each other, which can negatively affect the radiation direction.Grinding and polishing the fiber after installation can result in a beveled end face, for example, oriented non-perpendicular to the optical axis of the fiber, which can increase retroreflection, reduce light incidence on target, and contribute to light being refracted away from the intended target or even undesirably striking the camera chip.

[0101] Thus, in accordance with one aspect of the present disclosure, the present application relates generally to an endoscope having a light guide including at least one light guide fiber, but is not limited to an endoscope with a light guide including at least one light guide fiber having a diameter of at least 80 μm, which at least partially reduces the above-mentioned problems of the prior art.

[0102] Thus, in one variant, it may be envisioned that the endoscope generally, but not limited to, has a housing or housing member, which is simplified in installation due to a special configuration of the light guide, preferably with only a few individual fibers, instead of relatively thick fibers with a diameter of 80 μm or more. The housing or housing member may have a camera chip receiving portion for positioning the camera chip and orienting the light guide fibers. It may be envisioned that the camera chip is preferably positioned in a predetermined manner in the center of the housing or housing member. Preferably, the housing or housing member may have one or more receiving portions on its outer surface for receiving, or orienting, and / or positioning one or more light guide fibers in a predetermined manner, and in this case, it is particularly preferred that the receiving portions have a cross section that is preferably trapezoidal or trough-shaped, preferably with obliquely extending side walls. In another embodiment, no cutout portion is provided, and the housing may be formed integrally from a single material surrounding the optical fiber, which is usually arranged or can be arranged in a slit-shaped portion. The housing may extend along the length of the optical fiber to provide additional stability to the fiber.

[0103] In other words, in one embodiment, the endoscope may have a separate housing member, which may already contain a housing or a camera chip, and the housing member may have one or more receiving sections for, on the one hand, positioning the camera chip in a predetermined position in its center and, on the other hand, for receiving, orienting, and / or positioning one or more light guide fibers in a predetermined position, the receiving sections preferably having a trapezoidal or trough-shaped cross section with obliquely extending side walls in one embodiment. This may at least partially overcome, or even optimally minimize or eliminate, several of the above-mentioned problems simultaneously. For example, the optical fiber may be mounted with its axis oriented parallel to the camera, thereby reducing the fiber's tilt and avoiding oblique drag. In this case, the obliquely extending side walls of the preferably trapezoidal or trough-shaped receiving section, for example, may allow the fiber position to be self-adjusted.

[0104] In one embodiment, it may be envisioned to use an opaque or dark-colored, particularly black-colored, material for the housing. This is advantageous because it provides a barrier to scattered light between the light guide fiber and the camera chip. This largely eliminates the aforementioned negative effects on image quality. It is even more advantageous if a polymer material, which can be manufactured by injection molding, is used for the housing. This allows for low costs on the one hand and allows for relatively complex geometries on the other hand. Furthermore, additional electrical insulation can be achieved. Examples of materials suitable for such an embodiment are polycarbonate (PC), ABS (acrylonitrile butadiene styrene), and polyamide (PA).

[0105] Thus, instead of the opaque or black-colored adhesives used in conventional fiber bonding, transparent adhesives, particularly UV-curable adhesives, can be used in the above-described embodiments, which can reduce installation complexity due to shorter curing times. Another advantage arises from the fact that the optical fiber can be positioned slightly recessed relative to the distal camera face; in this case, the optical fiber only needs to be folded and filled with a visually transparent compound, such as an epoxy resin or UV-curable compound, which eliminates the need for grinding and polishing the optical fiber and does not damage the camera chip lens. Furthermore, strain relief for sensitive wires or flexible circuits can be achieved inside the housing.

[0106] It should be noted here that such an embodiment, e.g., a housing with a corresponding receptacle, can be used essentially with the above-mentioned advantages for the integration of light guide fibers and / or other optical components, such as the camera, or ray-guiding and shaping optical elements, or one or more light sources, at the distal or proximal end, and thus also for other endoscopes, where the fiber diameter used ultimately plays only a secondary role. Therefore, in one embodiment based on this aspect in particular, it may be envisioned that a light guide including at least one light guide fiber with a diameter of 30 μm to 70 μm may also be used. Furthermore, in this case, it may be possible in one embodiment for the light guide to be formed as a fiber bundle including a plurality of thin fibers with diameters of 30 μm to 70 μm. In another embodiment, the numerical aperture of the one or more light guide fibers is at least 0.7, preferably at least 0.8, and particularly preferably at least 0.85. Preferably, the core of the one or more light guide fibers contains a glass material, the composition of which is selected from the glass compositions and glass composition ranges for the core glass described above. In particular, the core of the glass fiber may consist mainly, ie at least 50% by weight, or substantially, ie at least 90% by weight, or even entirely, of such glass material.

[0107] One embodiment in which the core of one or more light guide fibers comprises such a glass material is thus suitable for use in a camera (here in particular a camera having an area of, for example, 1×1 mm 2 This is advantageous because a very good illumination of the field of view of the optical system (for so-called CMOS cameras) can be achieved.

[0108] In one alternative embodiment, the light guide fiber or fibers are formed such that the core glass and / or cladding glass of the light guide fiber or fibers are free of lead and / or other heavy metals apart from unavoidable trace amounts, and free of other critical elements such as antimony and / or arsenic and / or Cr(VI).

[0109] In one variant of the invention, as already mentioned above, it can be assumed that the light source is configured as an integral component of the plug connection, i.e., is integrated into the plug connection, preferably fixedly integrated into the plug connection. In this case, it can be assumed that the light source has a heat sink, for example in the form of a metal molding, within the plug connection. Alternatively or additionally, the light source can have an integrated LED driver, i.e., a driver integrated, preferably fixedly integrated, into the plug connection. In this case, the integrated LED or the integrated driver can be connected to the first component of the endoscope via electrical contacts. In this case, the driver can particularly advantageously be configured as a space-saving series resistor for the integrated LED, which can also be equipped with an additional protection diode, e.g., a Zener diode, as a voltage limiting means. Alternatively, a special constant current source can be used as an integrated circuit, providing a fixed constant current for operating the integrated LED. It is particularly advantageous if the first component of the endoscope already supplies a constant current to the integrated LED via electrical contacts. This means that an integrated LED driver circuit is no longer necessary, which saves construction space within the plug connection and minimizes heat loss, allowing the integrated LED to be operated at the maximum current without exceeding the permissible limit temperature on the surface of the plug connection.

[0110] Within the scope of this disclosure, an integrated component means a component that is mounted, preferably fixedly mounted, in another component. An integrated LED may therefore also refer to an integrated LED. Correspondingly, an integrated component of another component is mounted, preferably fixedly mounted, in the other component.

[0111] In this case, it has been found that a very efficient optical coupling can be achieved if the optical coupling between the integrated LED and at least one light guide fiber of the light guide is formed as a butt coupling. In this case, the at least one light guide fiber is glued directly to the chip of the integrated LED with a transparent adhesive. This is particularly advantageous if, as mentioned above, the light guide fiber is formed as a so-called wide-angle fiber with a numerical aperture (NA) of at least 0.8. This allows a large portion of the light emitted by the LED to be captured and guided to the distal end of the second component.

[0112] In most light-emitting diodes, the chip that emits light is protected by a film or cast into it to prevent direct contact with the surroundings, and this film can have a variety of geometric shapes. For example, the film can be flat, but it can also be curved toward or away from the chip, particularly in the shape of a lens or a truncated sphere. Correspondingly, bonding a light guide fiber means attaching the light guide fiber to this film.

[0113] Another aspect of the present invention relates to a single use endoscopic system comprising a first component and a separately sterile packaged second component, the second component preferably being or may be formed as a shaft, releasably connectable to the first component after removal from the sterile packaging, thereby providing an endoscope, particularly an endoscope according to an embodiment of the present disclosure.

[0114] Within the scope of this disclosure, the term "shank" refers to a second component of an endoscope that has only a very small cross section compared to its length, i.e., the shaft is configured to be thin compared to its length. This configuration of the second component as a shaft is advantageous precisely when examining extremely inaccessible areas with an endoscope and / or when used in medical technology.

[0115] One advantage of the endoscopic system according to the present disclosure is that it has multiple second components, particularly shafts, already sterile-packaged for multiple examinations in rapid succession, allowing for rapid examination of multiple areas or, in medical examinations, for multiple examinations of different patients in rapid succession while ensuring sufficient hygiene. Thus, it is advantageous for the endoscopic system according to the present disclosure that the second component can be removably coupled to the first component, thus enabling the advantages of a single-use endoscope, where at the same time, parts of the endoscopic system that do not necessarily need to be sterilized, for example for medical examinations or other medical applications, are housed within the first component that can be used multiple times.

[0116] In one embodiment, the second component is provided as an at least partially flexible stem, the stem having a flexible jacket of a tube, braided tube or shrinkable tube, which at least partially surrounds a light guide with at least one light guide fiber, as well as supply lines for the electrical supply to the camera chip and at least one return signal line, preferably leading in particular to a data and / or image post-processing unit, which may be provided in the first component. Such an arrangement with a particularly flexible stem is particularly suitable for medical applications.

[0117] In another embodiment, the second component is at least partially configured as a rigid shaft, the shaft having a rigid sleeve jacket that encloses the light guide with at least one light guide fiber as well as supply lines for the electrical supply to the camera chip and preferably return signal lines that lead to a data post-processing unit and / or an image post-processing unit that may be provided in the first component. Such an arrangement may be particularly advantageous, since in this case the components included in the second component, configured as a rigid shaft, can be better protected against mechanical loads. [Brief explanation of the drawings]

[0118] The invention will be further explained below with reference to the drawings, in which identical reference numerals represent identical or corresponding parts. [Figure 1] 1 is a schematic, not-to-scale, illustration of an endoscope according to one embodiment. [Figure 2] FIG. 10 is a schematic partial view of an endoscope according to another variant. [Figure 3] 3a-3e are schematic, not-to-scale, views of the distal end of an endoscope. [Figure 4] FIG. 1 shows a 3D-CAD model of the distal end of an endoscope equipped with a camera chip and a housing for the camera chip. [Figure 5] FIG. 1 shows a 3D-CAD model of the distal end of an endoscope equipped with a camera chip and a housing for the camera chip. [Figure 6] FIG. 1 shows a 3D-CAD model of the distal end of an endoscope equipped with a camera chip and a housing for the camera chip. DETAILED DESCRIPTION OF THE INVENTION

[0119] FIG. 1 is a schematic, not-to-scale, illustration of an endoscope 1 according to one embodiment. The endoscope 1 includes a first component 10 and a second component 20, with the first component 10 located on the right and the second component 20 located on the left. The second component 20 has a proximal end 22 connected to the first component 10. It may be envisioned that the proximal end 22 of the second component 20 connected to the first component 10 is configured to be detachable. That is, the two components 10 and 20 may be configured to be attached via a releasable connection. This may be particularly advantageous when one component is intended for single use only, while the other component, e.g., the first component 10, includes particularly valuable and / or expensive components intended for multiple uses. This may be particularly true when a special light source, such as a light source having at least one laser, is enclosed within one component, e.g., the first component 10. This applies in particular to the data processing unit and / or image processing unit 11, the high-value light source 13 with a high-performance LED chip 14 and its LED driver circuit 15, and also to a network part (not shown) which may also be a component of the first component 10.

[0120] The second component 20 further has a distal end 21 in which a camera chip 23 is arranged for taking images of the tissue surface 40. A light guide 26 having at least one light guide fiber 27 extends within the second component 20. The light guide fiber 27 is configured to guide the light of the light source 13 from the proximal end 22 of the light guide 26 to the distal end 21 and emit it at the distal end 21 in order to illuminate the tissue surface 40 as brightly and uniformly as possible. A supply line (not shown) for an electrical supply to the camera chip 23 also extends within the second component 20.

[0121] The light source 13 comprises at least one LED chip 14 supplied with electricity via an LED driver circuit. Furthermore, an optical interface 16 of the LED chip 14, which is used to receive an optical plug-in connection 28 of the second component 20, may be provided with an optical element 17 in the form of a lens or lens unit, for example, to couple the light of the LED chip 14 into a light guide fiber 27 at the proximal end 22 of the light guide 26.

[0122] Particularly from an assembly point of view, it may be advantageous if the light guide 26 has a maximum of 20, preferably a maximum of 10, light guide fibers 27, precisely when the second component 20 is intended for single use only. However, in general, there can be up to several hundred individual fibers 27 in the light guide 26, this depending on the corresponding fiber diameter and the resulting or desired thickness of the fiber bundle and thus of the light guide 26, and the number of fibers 27 can be selected accordingly.

[0123] Typical fiber diameters (or fiber thicknesses) of the light guide fibers 27 may be preferably in the range of 100 μm to 1000 μm, preferably up to 600 μm, particularly preferably up to 500 μm, with the maximum fiber diameter preferably being in the range of 100 μm to 400 μm, but also thinner fibers with diameters of 30 μm, 50 μm or 70 μm are conceivable.

[0124] In one embodiment, the light guide fiber 27 or the light guide fibers 27 are formed as step index glass fibers.

[0125] Preferably, the light guide fiber 27 and / or the light guide fibers 27 may be configured such that the numerical aperture (NA) relative to air of the at least one fiber 27 and / or the light guide fibers 27 is at least 0.7, preferably at least 0.8, particularly preferably at least 0.85. This may be particularly advantageous for obtaining a high CRI (Color Rendering Index) and in particular for obtaining a maximum light flux at the distal end 21.

[0126] Particularly from an assembly point of view, it may be advantageous if at least one light guide fiber 27 or multiple light guide fibers 27 are arranged in an optical plug-in connection 28, for example in the form of an entrance sleeve, at the proximal end 22 of the light guide 26, as also shown diagrammatically in FIG.

[0127] The second component 20 may be, for example, an at least partially flexible or at least partially rigid shaft. The second component may have, for example, a jacket. If the second component 20 is an at least partially flexible shaft, the jacket is flexible, in particular made of a tube, braided tube, or shrinkable tube. If the second component 20 is an at least partially rigid shaft, the jacket is preferably rigid and includes a sleeve or tube section. Without being limited to the illustrative examples shown here, the jacket generally at least partially surrounds a light guide 26 with at least one fiber 27, a supply line for supplying electricity to the camera chip 23, and preferably at least one return signal line 24, preferably a line leading to a data post-processing unit and / or an image post-processing unit 11, which may be provided in the first component 10.

[0128] One particularly preferred embodiment has proven to be a unit comprising seven light guide fibers 27 of approximately 200 μm thickness formed as so-called wide-angle fibers with an NA greater than 0.85, the seven light guide fibers 27 being arranged around the camera chip 23 and glued in an optical bayonet connection 28 at the proximal end 22. Alternatively, the seven light guide fibers 27 may be heat-fused in the optical bayonet connection 28. In general, however, it is also possible, and may even be preferred, for the heat-fused fibers to be present at the proximal end without a sleeve.

[0129] Similarly, FIG. 2 shows a schematic representation of a portion of the second component 20 of the endoscope, with the light source 13 being a component integrated into a plug-in connection 30 that forms the proximal end 22 of the second component together with the light guide 26 of the second component 20, in this case the light source 13 having at least one integrated LED 31 that directs the emitted light into at least one light guide fiber 27 of the light guide 26.

[0130] The light source 13 formed as an integrated component of the plug-in connection 30 may additionally have a heat sink 35 and / or an integrated LED driver circuit 32, in which case the integrated LED 31 or the integrated driver circuit 32 can be connected to the first component 10 of the endoscope via electrical contacts 34.

[0131] It has been found that a very efficient optical coupling can be achieved when the optical coupling between the integrated LED 31 and at least one light guide fiber 27 of the light guide 26 is formed as a butt coupling. In this case, the at least one light guide fiber 27 is glued directly to the end face of the chip of the integrated LED 31 with a transparent adhesive. However, an optical element 33 in the form of a simple lens or lens unit may additionally be required to collimate the light so that as much light as possible can be injected into the fiber 27. In particular, the use of a wide-angle fiber 27 with a large acceptance angle (more than 100°) often leads to significantly improved results compared to a direct butt coupling, as Fresnel losses at another interface transition, here the optical element 33, can be avoided.

[0132] However, it may also be advantageous if the optical element 33 is formed as a transparent thin film, for example as a plastic film or thin glass. This prevents mechanical damage to the often extremely thin converter film of the LED chip of the integrated LED 31. That such a film also serves as a particularly effective mechanical protection can be seen in the embodiment shown in FIG. 1, where, for example, the optical element 17 can be formed as a plastic film or thin glass. This provides mechanical protection for the LED chip 14, especially in this embodiment where the optical plug-in connection 28 of the second component 20 is frequently inserted and removed from the optical interface 16.

[0133] For both the variant in which the LED chip is mounted in the first component of the endoscope and the variant in which the integrated LED chip is mounted in the plug-in connection of the second component, the LED chip is provided with a 1 mm 2Particularly high-performance compact white light LEDs are suitable, which have extremely high lumens per watt that can be generated at chip dimensions of 1 mm. In particular, this relatively small chip area allows for high coupling efficiency into the light guide fiber. An example of such an LED is the LUMILEDS LUXEON Z LXZ1-4080, which on the one hand allows a CRI of 80 and on the other hand has a chip size of 1 mm. 2 For a chip size of 1.4 W, it produces a luminous flux of 130 lm. Another example is the OSRAM OSLON Pure 1010, which allows a CRI of 90 and produces a luminous flux of 95 lm at 0.98 W.

[0134] Furthermore, with such LEDs, particularly in variants in which the LED is integrated into the plug connection, sufficiently large lm values ​​can be achieved even when the LED has to be operated at a controlled low current and therefore at a low power in order to maintain the maximum permissible surface temperature at the plug connection.

[0135] 3a-3e show schematic, not-to-scale, views of the distal end 21 of the second component 20 of the endoscope 1. The distal end 21 each includes a light guide 26, here each having a number of light guide fibers 27 as well as one camera chip 23 each.

[0136] In the left drawing of Fig. 3 (Fig. 3a), four fibers 27 are arranged, each having a circular cross section within the measurement accuracy. These fibers 27 are arranged around the camera chip 23, which here has an approximately square shape, with one fiber 27 on each side of the camera chip 23. In contrast, in the drawing of Fig. 3d, fibers 27 are arranged on only three sides of the camera chip 23.

[0137] In the view of Fig. 3b, only two fibers 27 are arranged on two sides of the camera chip 23. In this case, the cross section of the light guide fibers 27 is not circular, but rather elliptical or oval. In this case, the light guide fibers 27 may be similarly deformed at the distal end 21 compared to the proximal end 22 (not shown). In particular, the light guide fibers 27 may have a circular cross section at the proximal end 22, but similarly deformed at the distal end. This may be advantageous for arranging the fibers 27 so as to surround the camera chip 23.

[0138] Preferably, the plurality of light guide fibers 27 and / or at least one light guide fiber 27 may have, at least at their distal end 21, a flattened shape, as exemplarily shown here, in particular a cross-section with an aspect ratio of at least 1.5:1 and / or an elliptical cross-section and / or a kidney-shaped cross-section and / or a cross-section defined by at least two lines with different radii of curvature and / or a cross-section formed as the difference surface of two circles and / or ellipses that only partially overlap each other. Other cross-sectional shapes, for example polygonal, are also conceivable, but it is precisely the flattened shape that is particularly advantageous for the arrangement of the light guide fibers 27 surrounding the camera chip 23. In the arrangement shown in FIG. 3c, four fibers having cross-sections at their distal ends formed as circular segments are arranged to surround the camera chip 23. Without being limited to the example of a cross-section as a circle segment specifically shown here, that is, which may also be designated here, for example, as "D", in general, a cross-section defined by at least two lines with different radii of curvature and / or formed as the difference surface of two circles and / or ellipses that only partially overlap each other is possible and advantageous. For example, a sickle-shaped cross-section is generally possible.

[0139] The distal end of fiber 27 shown in both Figures 3b and 3c can be deformed in this way, for example, by a hot deformation process. In this case, fiber 27 is heated in a mold by its processing heat and then deformed under pressure. Due to the viscosity of the fiber material, it is naturally impossible to replicate a perfect geometric shape. Therefore, a cross section in the shape of a circular segment, sometimes described as "D-shaped," will have relatively small rounded corners. In principle, such shaping can be applied to glass fiber, quartz fiber, or plastic fiber, and in this case, the deformation temperature can be adapted to each material. For plastic fiber (POF), the deformation temperature is typically 150°C to 300°C; for glass fiber, it is typically 500°C to 800°C depending on the type of glass; and for quartz fiber, it can be up to 2000°C.

[0140] 3e shows a 12-fiber arrangement, as already mentioned above. In this case, four thicker fibers 27 are grouped together with eight thinner fibers, with the thicker fiber 27 in the center of the cavity and the two thinner fibers 27 on either side of the thicker fiber 27 per cavity (segment). This allows for a good utilization of the cavity's surface area and thus a relatively high luminous flux, despite the relatively small number of fibers 27. This example can also be extended to a 20-fiber arrangement, for example, with 20 individual fibers 27, i.e., five fibers 27 per cavity, in which case there are ideally three diameter stages in the fibers 27.

[0141] FIG. 4 shows a 3D-CAD model of the distal end 21 of the second component 20 of an endoscope according to an embodiment in which twelve light guide fibers 27 of the same diameter are arranged around the camera chip 23. In one embodiment, the endoscope has a housing 41, which, without being limited to the illustrated example, includes a receptacle for the camera chip 23 for fixing the chip 23 in position. The housing may, for example, have multiple receptacles 42 corresponding to the light guide fibers 27, allowing the receptacles 42 to position the light guide fibers 27 in a predetermined manner with respect to their position and angular orientation. For this purpose, the receptacle according to the embodiment shown in FIG. 4 is trough-shaped or trapezoidal. This has the advantage that the fibers 27 can be positioned in a correspondingly parallel arrangement already. Inclined and therefore obliquely pulled fibers 27, with the associated radiation defects at the distal end 21, can be avoided by this configuration of the housing 41 and the receptacles 42. This also reduces the installation effort. Alternatively, the housing may be formed, for example, from a single material, ie, integrally, and may enclose the optical fiber as shown in FIG.

[0142] In Figure 5, the same unit as in Figure 4 is shown assembled in the rigid shaft of the second component 20 of the endoscope. It can be seen that for the component described in Figure 4, the fibers 27 are guided substantially parallel in the receptacle 42 of the housing 41.

[0143] It should be noted that the housing 41 may be partially or sectionally surrounded by a rigid or flexible sleeve, which may, for example, assist in the subsequent positioning of the light guide fibers in the receiving portion 42 and further simplify subsequent installation. In particular when using fewer, relatively thick fibers, it is also conceivable for the housing 41 and the sleeve to be formed in one piece, and the light guide fibers may be inserted into existing, often slit-like, portions or recesses. This is shown in FIG. 6.

[0144] Ideally, to shield the camera chip 23 from lateral external light from the light guide fiber 27, the housing 41 is made of an opaque, light-impermeable material. Particularly suitable for this purpose are injection-molded components made of black-colored plastic, such as those made of or containing polycarbonate (PC) and / or polyamide (PA). Furthermore, it is conceivable to use an opaque adhesive, also black-colored, for example, for fastening the fiber. However, a housing 41 made of, for example, black plastic also allows the use of a transparent adhesive, such as a UV-curable adhesive, which shortens the manufacturing process and thus offers cost advantages.

[0145] Additionally, a feedback signal line 24 is shown. [Explanation of symbols]

[0146] 1. Endoscope 10 First component of endoscope 11 Data processing unit and / or image processing unit 13 Light source 14 LED chips 15 LED drive circuit 16 Optical Interface 17 Optical Elements 20 Second component of endoscope 21 Distal end of second component 22 proximal end of second component 23 Camera Chip 24 Return signal line 25 Electrical plug connections 26 Light Guide 27 Light guide fiber 28 Optical bayonet connection 30 Plug-in connection 31 Integrated LEDs 32 Integrated LED driver circuit 33 Optical Elements 34 Electrical Contacts 35 Heatsink 40 Tissue surface 41 Housing 42 Storage section

Claims

1. An endoscope (1) having a first component (10) and a second component (20), the second component (20) has a proximal end (22) connected to the first component (10), preferably a detachably connected proximal end (22) and a distal end (21), and an image capturing element, such as a camera chip (23) or an optical fiber element, is disposed at the distal end (21), and a light guide (26) having at least one light guide fiber (27) extends within the second component (20) to guide light from a light source (13) from the proximal end (22) to the distal end (21) and emit it at the distal end (21), and preferably a supply line for supplying electricity to the camera chip (23); The first component (10) incorporates the light source (13), the light source (13) having at least one LED chip (14) that emits light, the LED chip (14) being coupled to the proximal end (22) of the second component (20) coupled to the first component (10) so that light emitted from the LED chip (14) can enter at least one light guide fiber (27) of the light guide (26); Alternatively, the light source (13) is accommodated in a plug-in connection (30) as a component of the plug-in connection (30), which plug-in connection (30) forms the proximal end (22) of the second component together with the light guide (26) of the second component, and the light source (13) comprises at least one LED (31) integrated, preferably fixedly integrated, in the light source (13), which LED (31) directs its emitted light into at least one light guide fiber (27) of the light guide (26), At least one of the light guide fibers (27) has a diameter of at least 80 μm, and at least one of the light guide fibers (27) has a protective cover made of a polymer-based coating and / or a polymer-based tubing material arranged at least partially and / or sectionally on its outer surface. Endoscope (1).

2. The light guide (26) has a maximum of 20, preferably a maximum of 10 light guide fibers (27). An endoscope (1) according to claim 1.

3. the light guide fiber (27) or the light guide fibers (27) have a diameter in the range of 100 μm to 1000 μm, preferably in the range up to 600 μm, particularly preferably in the range up to 500 μm, very particularly preferably in the range from 150 μm to 400 μm, the individual light guide fibers (27) may each have a different diameter; An endoscope (1) according to claim 1 or 2.

4. the light guide fiber (27) or the light guide fibers (27) are step-index glass fibers, preferably the light guide fiber (27) or the light guide fibers (27) are step-index glass fibers having a glass composition that does not contain lead and / or other heavy metals, apart from unavoidable trace amounts, and does not contain other critical elements such as antimony and / or arsenic and / or Cr(VI); An endoscope (1) according to any one of claims 1 to 3.

5. the numerical aperture (NA) of the light guide fiber (27) or of the light guide fibers (27) in air is at least 0.7, preferably at least 0.8, particularly preferably at least 0.85; An endoscope (1) according to any one of claims 1 to 4.

6. The light guide (26) comprises a plurality of light guide fibers (27), at least one light guide fiber (27), preferably a plurality of light guide fibers (27), particularly preferably all light guide fibers (27), having a protective cover made of a polymer-based coating and / or a polymer-based tubing material arranged at least partially and / or sectionally on their outer circumferential surface. An endoscope (1) according to any one of claims 1 to 5.

7. the coating comprises an acrylate copolymer, a polyurethane copolymer, a polyimide copolymer, an epoxy copolymer, a polyamide copolymer, an ethylene-tetrafluoroethylene copolymer, or a polyxylol-based compound, or a mixture of one or more of these compounds, or consists of one of the said compounds or a mixture of one or more of the said compounds, An endoscope (1) according to any one of claims 1 to 6.

8. The coating can be or has been applied to the light guide fiber(s) (27) at low pressure by dipping, spraying, extrusion or deposition, preferably immediately after drawing of the light guide fiber(s) (27). An endoscope (1) according to any one of claims 1 to 7.

9. the coating has a thickness of at least 5 μm and at most 100 μm, preferably at least 10 μm and at most 50 μm; An endoscope (1) according to any one of claims 1 to 8.

10. the endoscope (1) has a further outer coating, which preferably comprises PMMA, polyamide (NYLON), polyimide or a fluorinated polymer such as ethylene-tetrafluoroethylene copolymer (abbreviated ETFE) commercially available, for example, under the trade name TEFZEL®, or a thermoplastic elastomer, for example a thermoplastic polyester elastomer or a thermoplastic copolyester elastomer, for example, commercially available, for example, under the trade name Hytrel®, and / or polyvinylidene fluoride, for example, available under the trade name Kynar®, or polytetrafluoroethylene, for example, available under the trade name Teflon®, or polyurethane or a mixture thereof; An endoscope (1) according to any one of claims 1 to 9.

11. the light guide fiber (27) or the light guide fibers (27) are arranged in an optical plug-in connection (28) formed as an entrance sleeve at the proximal end (22) of the second component; An endoscope (1) according to any one of claims 1 to 10.

12. The light guide fiber (27) is disposed at the proximal end (22) by high temperature melting. An endoscope (1) according to any one of claims 1 to 11.

13. At least one light guide fiber (27) and / or a plurality of light guide fibers (27) and / or the light guide (26) at the distal end (21) are deformed compared to the proximal end (22). An endoscope (1) according to any one of claims 1 to 12.

14. the at least one light guide fiber (27) and / or the plurality of light guide fibers (27) have, at least at the distal end (21) of the light guide (26), a cross-section with a flattened shape having an aspect ratio of at least 1.5:1 and / or an elliptical cross-section and / or a kidney-shaped cross-section and / or a cross-section defined by at least two lines with different radii of curvature and / or a cross-section formed as the difference surface of two circles and / or ellipses that only partially overlap each other, An endoscope (1) according to any one of claims 1 to 13.

15. the light source (13) may be formed integrally, preferably rigidly integrated, in the plug connection (30) and / or may have a heat sink (35) and / or an integral, preferably rigidly integrated LED driver circuit (32), the integral, preferably rigidly integrated LED (31) or the rigidly integrated LED driver circuit (32) being connectable to the first component (10) of the endoscope (1) via electrical contacts (34); An endoscope (1) according to any one of claims 1 to 14.

16. an optical coupling between the integrated, preferably immovably integrated LED (31) and the at least one light guide fiber (27) of the light guide (26) is formed as a butt coupling, and the at least one light guide fiber (27) is directly glued to the chip of the integrated, preferably immovably integrated LED (31) by a transparent adhesive; An endoscope (1) according to any one of claims 1 to 15.

17. The endoscope (1) further comprises a housing (41) having a receiving section for the camera chip (23) for positioning the camera chip (23), preferably for a predetermined positioning in the center of the housing (41), and one or more receiving sections (42), preferably on the outer surface of the housing (41), for a predetermined reception, orientation and / or positioning of the light guide fiber (27) or of several light guide fibers (27), particularly preferably having a trapezoidal or trough-shaped cross section, preferably with obliquely extending side walls. An endoscope (1) in particular according to any one of claims 1 to 16.

18. the housing (41) is made of or comprises a polymer material which can be produced by injection molding techniques, and which comprises or is made of an opaque or dark, in particular black-coloured, material, and is particularly preferably made of or comprises a polymer material which can be produced by injection molding techniques, Endoscope (1) according to claim 17.

19. A single-use endoscope system comprising a first component (10) and an individually sterile-packaged second component (20), The second component (20) is preferably or may be formed as a shaft and is removably connectable to the first component (10) after removal from the sterile packaging, thereby resulting in an endoscope (1) according to any one of claims 1 to 18. Single-use endoscopy system.

20. The second component (20) is provided in the form of an at least partially flexible shaft, which has a flexible jacket made of a tube, a braided tube or a shrinkable tube, which at least partially surrounds the light guide (26) with at least one light guide fiber (27), as well as the supply lines for the electrical supply to the camera chip (23) and preferably at least one return signal line (24), which leads in particular to a data post-processing unit and / or an image post-processing unit (11) which may be provided as a component in the first component (10).

20. The single use endoscope system of claim 19.

21. The second component (20) is provided at least partially in the form of a rigid shaft, the shaft having a rigid sleeve jacket which encloses the light guide (26) with at least one light guide fiber (27), as well as the supply lines for the electrical supply to the camera chip (23) and preferably at least one return signal line (24) leading to a data post-processing unit and / or an image post-processing unit (11) which may be provided as a component in the first component (10).

21. The single use endoscope system of claim 19 or 20.

Images