Imaging system for medical endoscopic system, which removes honeycomb artifacts from images from multicore optical fibres

Abstract

The invention relates to a system for imaging a target, comprising: - a medical endoscopic system (1) provided with two multicore optical fibres (11), (12), each having a plurality of cores (11c), (12c) separated by a separation structure (lld), (12d), - an image acquisition and processing apparatus (15), comprising: *at least one configured illumination source and at least one imaging sensor (18), (19) configured to receive light beams from the multicore optical fibres, the imaging sensor receiving the images from a configuration system (31) in order to create, on the imaging sensor, images of the target for which the position of the separation structure of the first multicore optical fibre is different from the position of the separation structure of the second multicore optical fibre; *an imaging processor (25) for reconstructing a composite image of the target.

Description

Description Title of the invention: Imaging system for a medical endoscopic system that eliminates the honeycomb effect in images of multi-core optical fibers Technical Field

[0001] The present invention relates to the technical field of imaging systems implemented within the framework of medical endoscopic systems in the general sense allowing access to the inside of a body such as a cavity or a canal for example and it aims more specifically at medical endoscopic systems, medical catheters and medical endoscopes.

[0002] The medical endoscopic system implemented within the framework of the present invention finds particularly advantageous applications for enabling access to the internal surface of a hollow organ, cavity or natural or artificial conduit of the human body in order to perform various operations for therapeutic, surgical or diagnostic purposes, and can be used in the field of the urinary tract, gastrointestinal tract, respiratory system, cardiovascular system, trachea, sinus cavity, female reproductive system, abdominal cavity or any other part of the human body to be explored by a natural or artificial route. Previous technique

[0003] Typically, a medical endoscopic system such as a medical catheter or endoscope consists of a control handle to which an insertion tube is attached. At the end opposite the handle, the tube has a distal tip. This insertion tube is of varying length and flexibility, allowing it to be inserted into a natural or artificial access site to perform various procedures or functions for therapeutic, surgical, or diagnostic purposes. It is worth noting that such an endoscopic system is designed with the smallest possible cross-section to allow access to sites with limited openings.

[0004] In a medical endoscopic system such as an endoscope, the distal end is equipped with a vision system that allows for the examination of organs, cavities, or ducts in the human body. Upstream of this distal end, the insertion tube includes a flexural structure or articulating section made up of hinged vertebrae that allow for the orientation of the distal end. This medical endoscope is designed to be connected to a medical electronic device that includes a signal processing unit for the image signals delivered by the endoscope's vision system. The images captured are displayed on a screen on this device or on a remote screen connected to it.

[0005] The vision system mounted at the distal end of the tube includes a camera, with or without one or more light sources such as LEDs. The camera, and / or the light sources, are electrically connected to electrical components located in the handle or the medical device. According to the embodiment described in US patent application 2022 / 0160218, the camera and light sources located at the distal end of the insertion tube are connected to electrical components located in the handle. It should be noted that a medical endoscopic system is generally used in an environment where various electrical equipment, such as electrosurgical units, X-ray machines, scanners, or monitors, are operating, which may affect the operation of the camera and / or the signal it delivers.Furthermore, in the case of a disposable endoscopic system, the light sources and camera are discarded. Moreover, these electronic components constitute electronic waste requiring recycling, increasing the cost of such a system.

[0006] It is also known by US patent 11,061,185, a medical endoscopic system comprising a multicore optical fiber composed of numerous cores separated by a matrix and housed in a common sheath. This multicore fiber receives radiation from a target at its distal end and transmits the radiation along its entire length to deliver the radiation to an imaging sensor at its proximal end. The medical endoscopic system also includes a light source delivering to the proximal end of an optical lighting fiber, a beam of light exiting the distal end of the lighting fiber to illuminate the target.

[0007] Such a medical endoscopic system requires the use of a multicore optical fiber and an illumination optical fiber to obtain a high-quality image of the target. However, due to the use of multicore fibers, a honeycomb-shaped pattern appears on the images, corresponding to the separation matrix of the cores of these multicore optical fibers. This separation structure hinders observation of the portion of the target located at the interface of this separation structure. Description of the invention

[0008] The object of the invention is to remedy the disadvantages of the prior art by proposing an imaging system that provides a complete image of the target while exhibiting insensitivity to electromagnetic interference and a reduction of electronic components as waste.

[0009] To achieve this objective, the imaging system according to the invention for a medical endoscopic system for visualizing a target comprises: - a medical endoscopic system comprising an insertion instrument terminating opposite a proximal part, with a distal head, this insertion instrument being provided with a first multicore optical fiber and a second first multicore optical fiber each having a distal end, a proximal end and a plurality of cores, separated by a separating structure, the distal ends of the first multicore optical fiber and the second multicore optical fiber being located at the distal head of the insertion instrument; - an image acquisition and processing device comprising: * at least one configured lighting source, to deliver a light beam according to at least one first spectrum of wavelengths, to the distal head of the insertion instrument; * at least one imaging sensor, configured to receive light beams from at least the proximal end of the first optical fiber multicore and the proximal end of the second multicore optical fiber, the imaging sensor receiving images from a configuration system to create on the imaging sensor, images of the target whose honeycomb position of the first multicore optical fiber is different from the honeycomb position of the second multicore optical fiber; *an imaging processor connected to the imaging sensor and configured to process images from the first multi-core optical fiber and the second multi-core optical fiber, to reconstruct a composite image of the target in which the honeycomb image does not appear.

[0010] According to one embodiment, the image acquisition and processing device comprises a single imaging sensor configured to receive either, in two separate areas, the light beams from the first multi-core optical fiber and the second multi-core optical fiber, or, in a common but time-shifted area, the light beams from the first multi-core optical fiber and the second multi-core optical fiber.

[0011] According to another embodiment, the image acquisition and processing device comprises two imaging sensors, each configured to receive a light beam from either the first multi-core optical fiber or the second multi-core optical fiber.

[0012] According to an advantageous implementation feature, the configuration system is configured so that images from the first multi-core optical fiber and images from the second multi-core optical fiber can be matched.

[0013] Advantageously, the imaging processor processes the images to determine an orientation of the distal head.

[0014] According to one example of implementation, the configuration system is implemented by the first multi-core optical fiber and the second multi-core optical fiber having sections of different shapes.

[0015] According to another embodiment, the configuration system is achieved by the first multicore optical fiber and the second multicore optical fiber having different orientations.

[0016] According to another embodiment example, the configuration system is implemented by a first multi-core optical fiber and a second multi-core optical fiber with different numerical apertures.

[0017] According to another embodiment, the configuration system is achieved by an optical system disposed at the distal end of multicore optical fibers to create different depths of field.

[0018] According to another embodiment, the configuration system is achieved by the first multicore optical fiber having cores of a determined diameter while the second multicore optical fiber has cores with a diameter different from the diameter of the cores of the first optical fiber.

[0019] According to another embodiment, the configuration system is implemented by the first multicore optical fiber having a section of determined shape while the second multicore optical fiber has a section of different shape from the shape of the section of the first multicore optical fiber.

[0020] Advantageously, the lighting source is configured to deliver a light beam to at least one multi-core optical fiber.

[0021] According to another implementation example, a light source is configured to deliver a beam of light to an optical fiber carrying the light to the distal head of the insertion instrument.

[0022] According to an advantageous implementation feature, the imaging sensor(s) receive images from the configuration system configured to create on the imaging sensor(s), images from the two multi-core optical fibers containing target size indicators, and the imaging processor processes the images to determine a target measurement from the size indicators. Brief description of the drawings

[0023] [Fig. 1] Figure 1 is an overview of an example application of a remote imaging system for an endoscope as a medical endoscopic system for visualizing a target.

[0024] [Fig. 2] Figure 2 is an overview of another example of the application of a remote imaging system for an endoscope as a medical endoscopic system for visualizing a target.

[0025] [Fig. 3] Figure 3 is an overview of another example of the application of a remote imaging system for a catheter as a medical endoscopic system for visualizing a target.

[0026] [Fig. 4] Figure 4 shows an example of an over-resolution image in which the honeycomb pattern present in two images obtained using two multi-core optical fibers no longer appears.

[0027] [Fig. 5] Figure 5 schematically represents another example of the realization of a remote imaging system for a medical endoscopic system using two multicore optical fibers, a light source and an imaging sensor.

[0028] [Fig. 6] Figure 6 schematically represents another example of the realization of a remote imaging system for a medical endoscopic system using two multicore optical fibers, two light sources and an imaging sensor.

[0029] [Fig. 7] Figure 7 schematically represents another example of the realization of a remote imaging system for a medical endoscopic system using two multicore optical fibers, a light source and two imaging sensors.

[0030] [Fig. 8] Figure 8 schematically represents another example of the realization of a remote imaging system for a medical endoscopic system using two multicore optical fibers, two light sources and two imaging sensors.

[0031] [Fig. 9] Figure 9 schematically represents the distal head of a medical endoscope comprising two multicore optical fibers and showing a detail of a multicore optical fiber.

[0032] [Fig. 10] Figure 10 is a functional block diagram of an example implementation of a remote imaging system for a medical endoscopic system.

[0033] [Fig. 11] Figure 11 schematically represents another example of the realization of a remote imaging system for a medical endoscopic system using two multicore optical fibers, a light source and two imaging sensors as well as an additional lighting fiber.

[0034] [Fig. 12] Figure 12 schematically represents the distal head of a medical endoscope comprising two multicore optical fibers whose matrix positions are different, allowing images to be obtained with offset matrix positions for the target.

[0035] [Fig. 13] Figure 13 schematically represents the distal head of a medical endoscope comprising several lighting fibers and two multicore optical fibers whose cores have cores of different diameters.

[0036] [Fig. 14] Figure 14 schematically represents the distal head of a medical endoscope comprising two multicore optical fibers with sections of different shapes.

[0037] [Fig. 15] Figure 15 schematically represents another example of an imaging system implementation comprising an optical system arranged at the distal end of two multicore optical fibers to create different depths of field. Description of the implementation methods

[0038] As can be seen from the figures, the object of the invention relates to an imaging system I for a medical endoscopic system 1 of the endoscope or catheter type in the general sense, designed to access the interior of a body such as a cavity or a canal, for example. Typically, an endoscopic system 1 of the endoscope or catheter type comprises an insertion instrument 2 presenting a proximal part 2a and, opposite, a distal part forming a free end. The insertion instrument 2 thus terminates at its free end, with a distal head 2b from which a target C is visualized in the general sense.

[0039] According to an application in which the medical endoscopic system 1 is an endoscope (Figures 1, 2, and 9), the medical endoscopic system comprises, as an insertion instrument 2, an insertion tube 3 having a free end forming the distal head 2b and held at its opposite end by a control handle 4, all or part of which forms the proximal part 2a of the insertion instrument. The insertion tube 3 is temporarily or permanently fixed to the control handle 4. In the example illustrated in Figures 1 and 2, the insertion tube 3 is inserted, at its end opposite its free end, into a recess in a tip 3a intended to be fixed to the distal part of the control handle 4.This insertion tube 3, which has a greater or lesser length and flexibility, is intended to be introduced into a natural or artificial access route in order to perform various operations or functions for therapeutic, surgical or diagnostic purposes.

[0040] The insertion tube 3 is made of a semi-rigid material such as thermoplastic elastomer (TPE). The insertion tube 3 is available in lengths adapted to the length of the duct to be inspected, ranging from 5 cm to 3 m. The insertion tube 3 has various cross-sectional shapes, such as square, oval, or circular. This insertion tube 3, which comes into contact with tissues, human organs, or medical devices (trocars or probes), is primarily intended for single or multiple use by a single patient, or for reuse after decontamination, disinfection, or sterilization.

[0041] The endoscope-type endoscopic system 1 also includes, inside the insertion tube 3, a tubular conduit 6 forming an operating or working channel extending from the control handle 4 to the distal head 2b to allow, at the level of this distal head, the introduction of various tools and / or fluids and / or the aspiration of fluids (Figure 9). Tubular conduit 6 is surrounded by the insertion tube 3 along its entire length between the distal head 2b and the control handle 4. Classically, the tubular conduit 6 extends beyond the tip 3a inside the control handle 4.

[0042] Typically, the endoscope-type endoscopic system 1 also includes a control mechanism 8 for orienting the distal head 2b relative to the longitudinal axis of the insertion tube 3. For this purpose, the insertion tube 3 has, upstream of the distal head 2b, a flexing, folding, or pivoting structure 9 that allows the distal head 2b to be oriented relative to the longitudinal axis of the insertion tube 3. The control mechanism 8 can be designed in any suitable manner so that the distal head 2b can be moved between a rest position in which the insertion tube 3 is straight and a pivoted position in which the pivoting portion 9 is curved. For example, the control mechanism 8 may include a manual control lever that rotates a pulley to which at least one actuating cable is attached, mounted to be secured at the distal head 2b.

[0043] According to another application method in which the medical endoscopic system 1 is a catheter (Figure 3), the medical endoscopic system comprises, as an insertion instrument 2, a catheter terminating opposite a proximal portion 2a with a distal head 2b. This catheter may be of conventional design without an actuation system allowing movement of the distal portion along one or more axes. It may also be equipped with a deflection system with position recall via a shape-memory structure, such as a blade or a nitridol wire. Another actuation device for the distal portion may be implemented using cables or deformable parts that exploit the elasticity of the materials.

[0044] According to the invention, the insertion instrument 2 is provided with at least one first multicore optical fiber 11 and a second multicore optical fiber 12. Each multicore optical fiber 11, 12 has, respectively, a distal end 11a, 12a and a proximal end 11b, 12b. The end The distal lia, 12a of the multicore optical fibers is located at the distal head 2b of the insertion instrument 2 so as to visualize the target C. Each multicore optical fiber 11, 12 extends at least to the proximal part 2a of the insertion instrument and is provided with at least one optical connector 13 at its proximal end 11b, 12b.

[0045] Naturally, the optical connector 13, fitted to the proximal end 11b, 12b of the multicore optical fibers 11, 12, is designed to cooperate with a complementary male or female optical connector, depending on whether the optical connector 13 is male or female. Advantageously, a focusing lens is mounted in the complementary connector, improving the optical connection by providing a wider positioning tolerance. Indeed, the optical connector 13 may be intended to be discarded with the insertion tool. In this case, the optical connector 13 can be manufactured economically with significant tolerance variations.

[0046] As is known, a multicore optical fiber 11, 12 is an optical fiber comprising a multitude of cores 11c, 12c (Figure 9), for example at least 10,000 cores separated by a common coating or a separation structure such as an array lld, 12d. These cores 11c, 12c coated with the separation structure lld, 12d are mounted inside a common cladding lie, 12e. This separation structure lld, 12d of the cores 11c, 12c between them, presents, depending on the cross-section of the multi-core optical fiber, a honeycomb shape which appears on the images taken, in the form of a dark area G as illustrated in figure 4. For example, optical fibers marketed under the trade name ESKA by Mitsubishi Rayon Co., MBI by Asahi Kasei or FIGP by Fujikura can be used as multi-core optical fibers 11, 12.

[0047] The imaging system I also includes an image acquisition and processing unit 15 comprising a single light source 16 as in the variants illustrated in Figures 5 and 7, and a first light source 16 and a second light source 17 as in the variants illustrated in Figures 6 and 8. Each light source 16, 17 is configured to deliver a A light beam, according to at least a first wavelength spectrum, is transmitted to a multi-core optical fiber 11, 12 via the optical connector 13. Each illumination source 16, 17 is configured in any suitable manner to enable the multi-core optical fiber 11, 12 to deliver, at its distal end 11a, 12a, a light beam adapted to illuminate the target C to be imaged. For example, the illumination sources 16, 17 can be light-emitting diodes, halogen lamps, infrared light sources, or ultraviolet light sources. The image acquisition and processing device 15 also includes at least one imaging sensor 18, as in the embodiments illustrated in Figures 5 and 6, and a first imaging sensor 18 and a second imaging sensor 19, as in the embodiments illustrated in Figures 7 and 8.Each imaging sensor 18, 19 is configured to receive a light beam from the proximal end of a multicore optical fiber 11, 12, each equipped with the optical connector 13.

[0048] As can be seen from the various embodiments, it should be noted that the light sources 16, 17 and the imaging sensors 18, 19 are part of the image acquisition and processing unit 15 and are thus located remotely from the medical endoscopic system 1. It follows that if the medical endoscopic system 1 is disposable, the light sources 16, 17 and the imaging sensors 18, 19 can be reused with another medical endoscopic system 1, thereby reducing electronic waste. Furthermore, if the medical endoscopic system 1 requires decontamination, the image acquisition and processing unit 15 is not involved in such an operation, so the light sources 16, 17 and the imaging sensors 18, 19, which are part of this unit, are not likely to be damaged by this decontamination process.

[0049] It should be noted that in the application example illustrated in Figure 1, in which an endoscope is used as a medical endoscopic system 1, the proximal end of the multicore optical fiber(s), equipped with the optical connector 13, is located at the proximal part 2a of the insertion instrument, i.e. at the control handle 4. The multicore optical fibers 11, 12 are mounted inside the insertion tube 3 but outside the tubular conduit 6. The multicore optical fibers 11, 12 thus extend from the distal head of the insertion tube, inserting themselves along the entire length of the insertion tube 3, between the latter and the tubular conduit 6. The multicore optical fibers 11, 12 extend inside the control handle 4 to one or more optical connectors 13 mounted on the proximal part of the control handle 4.

[0050] According to this example, an optical cable 21 provides an optical link between the optical connector(s) 13 and the image acquisition and processing unit 15 to ensure the transmission of light beams between, on the one hand, the multi-core optical fibers 11, 12, and on the other hand, the light source(s) 16, 17 and the image sensor(s) 18, 19. The optical cable 21 can be made in any suitable manner in the form of one or more optical fibers. Typically, the optical cable 21 is provided, opposite its portion connected to the optical connector 13, with an optical connector 13a attached to the image acquisition and processing unit 15.

[0051] It should be noted that in the application example illustrated in Figure 2, where an endoscope is used as a medical endoscopic system 1, the proximal end of the multicore optical fibers, equipped with the optical connector 13, is directly connected to the image acquisition and processing unit 15. According to this example, the proximal end of the multicore optical fibers, equipped with the optical connector 13, is directly attached to the image acquisition and processing unit 15. Thus, the multicore optical fibers 11, 12 extend from the distal head of the insertion tube, inserting themselves along the entire length of the insertion tube 3, between the latter and the tubular conduit 6. The multicore optical fibers 11, 12 extend inside the control handle 4 to exit the proximal part of the control handle so as to be connected to the optical connector 13 attached to the acquisition and processing unit. 15 images.

[0052] It should be noted that in the application example illustrated in Figure 3, in which a catheter is used as a medical endoscopic system 1, this catheter is formed at least by the multicore optical fibers 11, 12, the distal end of which 11a, 12a forms the distal head 2b of the insertion instrument 2. Insofar as two multicore optical fibers 11, 12 are used, the insertion instrument 2 is formed by a protective sleeve in which the two multicore optical fibers 11, 12 are mounted. It should be noted that the proximal end of the multicore optical fibers 11, 12 is connected via the optical connector 13, either directly to the image acquisition and processing device 15 (as illustrated in Figure 3) or indirectly using the optical cable 21 (as explained in relation to Figure 1).

[0053] According to a first embodiment illustrated in Figure 5, the endoscopic system 1 comprises a first multi-core optical fiber 11 and a second multi-core optical fiber 12. The image acquisition and processing device 15 comprises: - a light source 16 configured to deliver a light beam to the first multi-core optical fiber 11, - a single imaging sensor 16 configured to present a first receiving zone for a light beam from the proximal end of the first multicore optical fiber 11 and a second receiving zone, separate from the first receiving zone, to receive a light beam from the proximal end of the second multicore optical fiber 12. It should be noted that the single imaging sensor 16 is configured to receive either on two separate zones, the light beams from the first multicore optical fiber 11 and the second multicore optical fiber 12, or on a common but time-shifted zone, the light beams from the first multicore optical fiber 11 and the second multicore optical fiber 12.

[0054] The image acquisition and processing device 15 comprises an optical separation system 22 disposed on the optical path between the proximal end of the multicore optical fiber 11 and the imaging sensor 18 and reflecting in direction of the proximal end of the multicore optical fiber 11, the light beam from the light source 16. This optical separation system 22 can be achieved by any suitable means such as a semi-reflective blade, a beam splitter or a prism optical system.

[0055] This example has the advantage of being able to obtain two images simultaneously which can be processed at the same time to achieve overresolution as will be described later in the description.

[0056] According to a second embodiment illustrated in Figure 6, the endoscopic system 1 comprises a first multi-core optical fiber 11 and a second multi-core optical fiber 12. The image acquisition and processing device 15 comprises: - a first lighting source 16 configured to deliver a light beam to the first multi-core optical fiber 11, - a second lighting source 17 configured to deliver a light beam to the second multi-core optical fiber 12, - a single imaging sensor 18 configured to present a first receiving area of ​​a light beam from the proximal end of the first multicore optical fiber 11 and a second receiving area separate from the first receiving area, to receive a light beam from the proximal end of the second multicore optical fiber 12.

[0057] The image acquisition and processing device 15 includes an optical separation system 22 disposed on the optical path between the proximal end of each multicore optical fiber 11,12 and the imaging sensor 18 and reflecting towards the proximal end of each multicore optical fiber 11, 12, the light beam from the lighting sources 16.

[0058] This example of a design allows the target to be illuminated with light beams exhibiting spectra of different wavelengths in order to obtain a spectrally super-resolution image. This solution offers the advantage of being able to visualize tumors. Indeed, by choosing a specific spectrum of wavelengths, the vascularization of the tissues can be highlighted. However, as a A tumor corresponds to a highly vascularized area; a tumor can be more easily observed by implementing this technique.

[0059] According to a third embodiment illustrated in Figure 7, the endoscopic system 1 comprises a first multi-core optical fiber 11 and a second multi-core optical fiber 12. The image acquisition and processing device 15 comprises: - a light source 16 configured to deliver a light beam to the first multi-core optical fiber 11, - a first imaging sensor 18 configured to receive a light beam from the proximal end of the first multi-core optical fiber H, - a second imaging sensor 19 configured to receive a light beam from the proximal end of the second multicore optical fiber 12.

[0060] The image acquisition and processing device 15 includes an optical separation system 22 disposed on the optical path between the proximal end of the multicore optical fiber 11 and the imaging sensor 18 and reflecting towards the proximal end of the multicore optical fiber 11, the light beam from the lighting source 16.

[0061] This example allows for overresolution imaging, as it's possible to acquire two images on two imaging sensors. It's also possible to acquire the images sequentially at different wavelengths.

[0062] According to a fourth embodiment illustrated in Figure 8, the endoscopic system 1 comprises a first multi-core optical fiber 11 and a second multi-core optical fiber 12. The image acquisition and processing device 15 comprises: - a first lighting source 16 configured to deliver a light beam to the first multi-core optical fiber 11, - a second lighting source 17 configured to deliver a light beam to the second multi-core optical fiber 12, - a first imaging sensor 18 configured to receive a light beam from the proximal end of the first multi-core optical fiber H, - a second imaging sensor 19 configured to receive a light beam from the proximal end of the second multicore optical fiber 12.

[0063] The image acquisition and processing device 15 includes an optical separation system 22 disposed on the optical path between the proximal end of each multicore optical fiber 11, 12 and the imaging sensor 18, 19 and reflecting towards the proximal end of each multicore optical fiber 11, 12, the light beam from the lighting sources 16, 17.

[0064] This example demonstrates the ability to obtain images with twice the resolution. One advantage of this solution is the ability to visualize tumors.

[0065] It should be noted that in figures 5 to 8, the proximal end of the multicore optical fibers, equipped with the optical connector 13, is schematically shown as being directly connected to the image acquisition and processing device 15. Of course, the proximal end of the multicore optical fibers 11, 12, equipped with the optical connector 13, can be located at the proximal part 2a of the insertion instrument so that an optical cable 21 provides the optical link between the optical connector 13 fixed to the control handle 4 and the image acquisition and processing device 15.

[0066] Similarly, it must be considered that the image acquisition and processing device 15 is configured to ensure the transmission of light between the imaging sensors 18, 19 and the optical connectors 13, 13a attached to the image acquisition and processing device 15. Likewise, the image acquisition and processing device 15 is configured to ensure, by all appropriate means, the transmission of light between the lighting sources 16, 17 and the optical connectors 13, 13a attached to the image acquisition and processing device 15.

[0067] It should be noted that, according to Figures 5 to 8, the multicore optical fibers 11 and 12 ensure, in particular, the transmission of the light flux from the illumination sources to the distal head 2b of the insertion instrument. It should also be noted, as illustrated in Figures 11 and 12, that the medical endoscopic system 1 may include at least one illumination optical fiber 28, and in the example shown in Figure 13, three illumination optical fibers 28, allowing for the delivery of additional light flux. This illumination optical fiber 28 has a distal end 28a and a proximal end 28b that receive the light flux from a light source 29.The distal end 28a of the lighting optical fiber 28 is located at the distal head 2b of the insertion instrument while the proximal end of the lighting optical fiber is located at the proximal part 2a of the insertion instrument being provided with an optical connector through which a light beam of illumination supplied by the light source 29 is routed.

[0068] The image acquisition and processing unit 15 also includes, as illustrated in Figure 10, an image processor 25 connected to the image sensors 18, 19 and configured to form images of the target C from the signals delivered by the image sensors 18, 19. The image processor 25 controls the image sensors 18, 19 to acquire images of the target at predetermined times. The image processor 25 also controls the illumination sources 16, 17 to regulate the emitted illumination, particularly during image acquisition by the image sensors 18, 19, as described later. The image processor 25 is connected to a display screen 26 for showing the images of the target C. This display screen 26 may be integrated into the image acquisition and processing unit 15 or be located separately from it.Of course, the 25 imaging processor can be connected to a memory for image recording.

[0069] The image acquisition and processing device 15 can take various forms. Typically, the image acquisition and processing device 15 can be in the form of an electronic tablet equipped The display screen 26 and a human-machine interface (HMI) allow a user to enter data or operate the device. This HMI can be a keyboard, a mouse, or the screen itself, for example, a touchscreen. The image acquisition and processing device 15 also includes a communication unit configured to communicate with a database, usually remote, that is part of a computer system.

[0070] The imaging system I according to the invention can be implemented in different ways which follow directly from the preceding description.

[0071] According to one example implementation, the illumination source(s) 16, 17 are configured to deliver light beams with different wavelength spectra, and the imaging sensor(s) 18, 19 are adapted to acquire images with different wavelength spectra. Typically, it can be considered to acquire images with different acquisition times before reconstructing them. Advantageously, the imaging processor 25 processes the images with different wavelength spectra to obtain a spectrally over-resolution image. In other words, the resulting image has a higher resolution than the resolution of the captured images.

[0072] According to an advantageous embodiment, the lighting source(s) 16, 17 are configured to deliver light beams according to red, green, and blue wavelength spectra, and the imaging sensor(s) 18, 19 are configured to acquire images of red (Ir), green (Iv), and blue (Ib) wavelength spectra. In the example illustrated in Figure 10, the first light source 16 is driven to deliver a light beam according to a red wavelength spectrum, and the first imaging sensor 18 is configured to acquire red wavelength spectral images Ir. The second illumination source 17 is configured to successively deliver light beams according to green and blue wavelength spectra and the second imaging sensor 19 is configured to acquire green wavelength spectra Iv and blue Ib images.

[0073] Furthermore, the imaging processor 25 processes spectral images of varying wavelengths to obtain a contrasted or colored image In, which can be a white image. In the illustrated example, the imaging processor 25 processes spectral images of red (Ir), green (Iv), and blue (Ib) wavelengths to obtain a white image In. Typically, for a CMOS imaging sensor 18, 19 with a Bayer matrix, each image of red (Ir), green (Iv), and blue (Ib) wavelengths has, for example, a resolution of 40,000 pixels. Processing these images results in a white image with a resolution of 120,000 pixels.

[0074] According to another advantageous embodiment, the lighting source(s) 16, 17 are configured to successively deliver light beams according to spectra of different wavelengths such as infrared light radiation and ultraviolet light radiation.

[0075] In another implementation example, the imaging processor 25 drives the imaging sensor(s) 18, 19 to acquire time-shifted images. The imaging processor 25 then processes these time-shifted images to obtain a temporally enhanced image. Thus, the imaging processor 25 processes a series of images taken successively in time to produce a resulting image with improved resolution compared to the resolution of each individual image.

[0076] In another implementation example, the imaging processor 25 drives the imaging sensor(s) 18, 19 to acquire spatially offset images with an overlapping area. These images are spatially offset due to the movement of the insertion instrument 2 or the offset of the two multi-core optical fibers at the distal head 2b. The imaging processor 25 processes the spatially and temporally offset images to obtain a spatially enhanced image. Thus, the imaging processor 25 processes a series of images taken successively from different positions of the distal head to obtain a resulting image with improved resolution compared to the resolution of each individual image.

[0077] Super-resolution spatial, temporal, and spectral images are created using image processing algorithms based on multi-image super-resolution methods. These methods are based on three different approaches known by the English names: Interpolation-Based Approaches; Frequency Domain-Based Approaches; and Reconstruction-Based Approaches. These methods are briefly described in the following publications: 1 - S. Borman and R. Stevenson, Super-Resolution from Image Sequences: A Review, in Midwest Symposium on Circuits and Systems, Notre Dame, IN, USA, 1998, pp. 374-378. SC Park, MK Park, and MG Kang. 2 - Super-Resolution Image Reconstruction: A Technical Overview, IEEE Signal Processing Magazine, vol. 20, no. 3, pp. 21-36, 5200. 3 - C. Mancas-Thillou and M. Mirmehdi, An Introduction to Super-Resolution Text, in Digital Document Processing, ser. Advances in Pattern Recognition. Springer London, 2007, pp. 305-327.4- Tian and K.-K. Ma, A survey on super-resolution imaging, Signal, Image and Video Processing (SIViP), vol. 5, no. 3, pp. 329-342, 2011.

[0078] As follows from the various embodiments above, at least one imaging sensor 18, 19 is configured to receive light beams from the proximal end of the first multicore optical fiber 11 and the proximal end of the second multicore optical fiber 12. According to the invention, the imaging sensor 18, 19 receives images from a configuration system 31 to create on the imaging sensor 18, 19, images of the target C whose position relative to the target, of the separation structure or matrix 11d of the first multicore optical fiber 11 is different from the position relative to the target, of the separation structure or matrix 12d of the second multicore optical fiber 12.

[0079] The imaging processor 25 is configured to process images from the first multi-core optical fiber 11 and the second multi-core optical fiber 12, to reconstruct a composite image of the target in which the image of the matrices or separation structures 11d, 12d does not appear. Indeed, given the presence of a separation structure 11d, 12d of the cores 11c, 12c for each multi-core optical fiber 11, 12, the images 11d and 12d are not present. Images 112 (Figure 4), taken from the light radiation carried by the first multicore optical fiber 11 and the second multicore optical fiber 12 respectively, reveal dark areas G in the shape of a grid or honeycomb, corresponding to images of the separation structure 11d, 12d of the multicore optical fibers. These dark areas G correspond to regions of the target C that are not observed by the imaging sensors.

[0080] The principle of the invention is such that the light fluxes carried by the first multicore optical fiber 11 and the second multicore optical fiber 12 cover an entire area of ​​the target C. Since the position of the 11d matrix of the first multicore optical fiber 11 on the imaging sensor differs from the position of the 12d matrix of the second multicore optical fiber 12 on the imaging sensor, the entire area of ​​the target C is observed. Naturally, the observed area of ​​the target C corresponds to the common area of ​​the target observed by both multicore optical fibers 11 and 12. It should be noted that the fields of view of the two multicore optical fibers may not coincide. In this case, only the common portion of the fields of view of the two multicore optical fibers allows the reconstruction of a composite image lacking the image of the separation structures 11d and 12d.

[0081] The imaging processor 25 is configured to construct a composite image from the images 11 from the first multi-core optical fiber 11 and the images 112 from the second multi-core optical fiber 12. Missing parts of an image from the first multi-core optical fiber 11 corresponding to the dark area G are reconstructed from parts of an image from the second multi-core optical fiber 11 that do not correspond to a dark area of ​​said image. In other words, the missing part of an image from the first multi-core optical fiber is completed by the corresponding part of an image from the second multi-core optical fiber. Conversely, the missing part of an image from the second multi-core optical fiber is completed by the corresponding part of an image originating from the first multi-core optical fiber. In the composite image thus constructed, the image of the matrices, that is to say, the image of the separation structure 11d, 12d of the cores of the two multi-core optical fibers 11, 12, as illustrated in Figure 4, does not appear. Such an over-resolution image makes it possible to obtain an image of the entire target with improved resolution. For the purposes of the invention, it is accepted that the composite image thus reconstructed may include one or more undefined areas corresponding to dark zones.

[0082] Naturally, the imaging processor 25 implements image processing programs that, from the images 11 and 112 taken from the multi-core optical fibers 11 and 12, construct a composite image. Such image processing programs may use neural networks that have undergone a training phase with reference images of targets.

[0083] Of course, the configuration system 31 for creating images of target C whose position on the imaging sensor, of the lld matrix of the first multicore optical fiber 11 is different from the position on the imaging sensor, of the 12d matrix of the second multicore optical fiber 12 can be realized in any appropriate way.

[0084] According to an advantageous feature of the invention, at least one embodiment of the configuration system 31 described below is adapted to create images on the imaging sensor(s) from the two multicore optical fibers and containing target size indicators. The images thus created are processed by the imaging processor 25 to determine a target measurement from the size indicators present in the images. As will be apparent from the examples described below, the target size indicators are related to the physical characteristics of the multicore optical fibers 11, 12, such as, for example, the diameter of the cores 11c, 12c, the diameter of these multicore optical fibers, the thickness of the matrices 11d, 12d, or the shapes of the cross-sections of the multicore optical fibers 11, 12.

[0085] According to an advantageous embodiment, the configuration system 31 is implemented by the first multicore optical fiber 11 and the second fiber Multicore optical fibers 12 with different orientations (Figure 12). In this example, the first multicore optical fiber 11 and the second multicore optical fiber 12 are of the same fiber type, and the distal ends 11a, 12a of these multicore optical fibers 11, 12 are positioned at the distal head 2b such that these multicore optical fibers 11, 12 observe the target with separation structures 11d, 12d that are spatially offset from each other. It should be noted that two multicore optical fibers 11, 12 can be used to perform target size measurements from the target images acquired by these two multicore optical fibers. Indeed, the separation structures 11d, 12d can serve as size indicators to determine a target size measurement.

[0086] According to another advantageous embodiment, the configuration system 31 is implemented by the first multicore optical fiber 11 having cores 11c of a predetermined diameter, while the second multicore optical fiber 12 has cores 12c with a diameter different from that of the cores of the first optical fiber. In the example illustrated in Figure 13, the cores 11c of the first multicore optical fiber 11 have, for example, a smaller diameter than the cores 12c of the second multicore optical fiber 12.

[0087] According to the example above, the two multicore optical fibers 11 and 12 have the same cross-section, i.e., the same diameter. It should be noted that, according to another advantageous embodiment, the configuration system 31 can be implemented using the first multicore optical fiber 11 and the second multicore optical fiber 12 with different cross-sections. Thus, the diameter of the first multicore optical fiber 11 can be smaller than the diameter of the second multicore optical fiber 12. It should be noted that the implementation of two multicore optical fibers 11 and 12 of different but known dimensions can be used as size indicators to perform target dimension measurements from the target images acquired by these two multicore optical fibers.

[0088] According to another advantageous embodiment, the configuration system 31 is implemented by the first multicore optical fiber 11 having a specific cross-sectional shape, while the second multicore optical fiber 12 has a cross-sectional shape different from that of the first optical fiber. In the example illustrated in Figure 14, the first multicore optical fiber 11 has a square cross-section, while the second multicore optical fiber 12 has a round cross-section. It should be noted that the implementation of two multicore optical fibers 11 and 12 with cross-sectional shapes can be used as size indicators to perform target dimension measurements from the target images acquired by these two multicore optical fibers.Indeed, since the dimensions of the cross-sections of these two multi-core optical fibers are known, it is possible to perform target measurements on the images taken from these two multi-core optical fibers.

[0089] According to another advantageous embodiment, the configuration system 31 is implemented by an optical system 31a, 31b arranged at the distal end of the multicore optical fibers 11, 12 to create different depths of field. As shown in Figure 15, the optical system may, for example, include a first lens 31a arranged at the distal end 11a of the first multicore optical fiber 11 to observe the target C at a depth of field Pfl. A second lens 31b is arranged at the distal end 12a of the second multicore optical fiber 12 to observe the target C at a depth of field Pf2, which is different from the depth of field Pfl.

[0090] According to another advantageous embodiment, the configuration system 31 is implemented by using a first multicore optical fiber 11 and a second multicore optical fiber 12 having different numerical apertures. Thus, since the aperture of a multicore optical fiber 11, 12 defines its field of view, the images obtained by multicore optical fibers with different apertures are different. [0091JII It is clear from the preceding description that the configuration system 31 can be implemented by one or more of the embodiments described above. In other words, it should be understood that these various embodiments of the configuration system 31 can be combined in any suitable manner. For example, the multicore optical fibers 11, 12 can have cores of different diameters as well as cross-sections of different shapes.

[0092] According to an advantageous embodiment, the configuration system 31 is configured so that the images 11 from the first multi-core optical fiber 11 and the images 112 from the second multi-core optical fiber 12 can be matched. Indeed, to reconstruct the missing parts of one image using the corresponding parts of another image, the positions of the images must be referenced to each other. The determination of the relative positions of the images can be carried out in any suitable manner. For example, the implementation of a marker or a label appearing on the acquired images allows this matching, provided that the relative positioning of the distal ends 11a, 12a of the multi-core optical fibers 11, 12 at the distal head 2b of the insertion instrument is known. [0093JII It should be noted that the implementation of two multicore optical fibers 11, 12 with cross-sections of different shapes can be used to match the images taken by the multicore optical fibers 11, 12. Indeed, since the relative positioning of the multicore optical fibers 11, 12 at the distal head 2b of the insertion instrument is known, it is possible to determine the relative position of the images from their characteristic shape. Advantageously, the imaging processor 25 processes the images from the two multicore optical fibers 11, 12 to determine an orientation of the distal head 2b. Indeed, the images from the two multicore optical fibers 11, 12 with cross-sections of different shapes exhibit orientation indicators that allow the orientation of the distal head to be determined.] 2b since the relative orientation of the two multicore optical fibers 11, 12 is known at the level of the distal head 2b.

[0094] According to another aspect, an imaging system I comprising two multicore optical fibers 11, 12 with sections of different shapes can be advantageously used to help localize the distal head relative to the target.

Claims

Claims

1. Imaging system for a medical endoscopic system for viewing a target comprising: - a medical endoscopic system (1) comprising an insertion instrument (2) ending opposite a proximal part (2a), by a distal head (2b), this insertion instrument being provided with a first multi-core optical fiber (11) and a second first multi-core optical fiber (12) each having a distal end, a proximal end and a plurality of cores (11c), (12c) separated by a separation structure (lld), (12d), the distal ends of the first multi-core optical fiber and the second multi-core optical fiber being located at the distal head of the insertion instrument; - an image acquisition and processing device (15) comprising: * at least one lighting source configured (16), (17) to deliver a light beam according to at least a first wavelength spectrum, to the distal head of the insertion instrument; * at least one imaging sensor (18), (19) configured to receive light beams coming at least from the proximal end of the first multi-core optical fiber and from the proximal end of the second multi-core optical fiber, the imaging sensor receiving the images from a configuration system (31) to create on the imaging sensor, images of the target whose position of the separation structure of the first multi-core optical fiber is different from the position of the separation structure of the second multi-core optical fiber; *an imaging processor (25) connected to the imaging sensor and configured to process the images from the first multi-core optical fiber and the second multi-core optical fiber, to reconstruct a composite image of the target in which the image of the separation structures does not appear.

2. Imaging system according to the preceding claim according to which the image acquisition and processing apparatus (15) comprises a single imaging sensor configured to receive either in two separate areas, the light beams coming from the first multi-core optical fiber (11) and the second multi-core optical fiber (12), or in a common area but offset in time, the light beams coming from the first multi-core optical fiber and the second multi-core optical fiber.

3. Imaging system according to claim 1 according to which the image acquisition and processing apparatus (15) comprises two imaging sensors (18), (19) configured to each receive a light beam coming from either the first multi-core optical fiber or the second multi-core optical fiber.

4. Imaging system according to one of claims 1 to 3, wherein the configuration system (31) is configured so that the images from the first multi-core optical fiber (11) and the images from the second multi-core optical fiber (12) can be matched.

5. An imaging system according to the preceding claim wherein the imaging processor (25) processes the images to determine an orientation of the distal head (2b).

6. Imaging system according to one of claims 1 to 5, wherein the configuration system (31) is produced by the first multi-core optical fiber (11) and the second multi-core optical fiber (12) having sections of different shapes.

7. Imaging system according to one of claims 1 to 6, wherein the configuration system (31) is produced by the first multi-core optical fiber (11) and the second multi-core optical fiber (12) having different orientations.

8. Imaging system according to one of claims 1 to 7, wherein the configuration system (31) is produced by a first multi-core optical fiber (11) and a second multi-core optical fiber (12) having different numerical apertures.

9. Imaging system according to one of claims 1 to 8, wherein the configuration system (31) is produced by an optical system arranged at the distal end of the multi-core optical fibers to create different depths of field.

10. Imaging system according to one of claims 1 to 9, according to which the configuration system (31) is produced by the first multi-core optical fiber (11) having cores according to a determined diameter while the second multi-core optical fiber (12) has cores with a diameter different from the diameter of the cores of the first optical fiber.

11. Imaging system according to one of claims 1 to 10, wherein the configuration system (31) is produced by the first multi-core optical fiber (11) having a section of determined shape while the second multi-core optical fiber (12) has a section of shape different from the shape of the section of the first multi-core optical fiber.

12. Imaging system according to one of the preceding claims, wherein the illumination source (16, 17) is configured to deliver a light beam to at least one multi-core optical fiber.

13. An imaging system according to one of the preceding claims wherein an illumination source (29) is configured to deliver a light beam to at least one optical fiber (28) carrying the light to the distal head of the insertion instrument.

14. Imaging system according to one of the preceding claims according to which the imaging sensor(s) receive the images from the configuration system (31) configured to create on the imaging sensor(s), images coming from the two multi-core optical fibers and containing size indicators of the target and in that the imaging processor (25) processes the images to determine a measurement of the target from the size indicators.

Images