Fiber Optic Rotary Joint with Hollow Shaft Motor

Abstract

A fiber optic rotary joint using a hollow shaft motor is disclosed. The fiber optic rotary joint (FORJ) connects a system console to a probe having a rotatable core and transmits rotational motion to the probe core. The FORJ includes a fixed optical fiber in optical communication with the rotatable optical fiber, a motor having a hollow shaft, and a fiber optic connector attached to the distal end of the hollow shaft. The motor is configured to rotate the rotatable optical fiber relative to the fixed optical fiber. The rotatable optical fiber is attached to the proximal end of the hollow shaft and connected to the fiber optic connector. The distal end of the fixed optical fiber is directly opposite to the proximal end of the rotatable optical fiber and is aligned with the proximal end of the rotatable optical fiber, so that the optical axis of the fixed optical fiber and the optical axis of the rotatable optical fiber are substantially colinear with the rotation axis of the motor. The fiber optic connector transmits optical power and torque to the probe core.

Description

Technical Field

[0001] The present disclosure relates generally to medical devices. More particularly, the present disclosure relates to a novel fiber optic rotary joint (FORJ) suitable for use in medical probes such as endoscopes, catheters, and the like. Background Art

[0002] In minimally invasive surgery, light can be guided to the target by an optical waveguide or optical conduit such as an optical fiber to obtain an optical image, perform optical measurements, perform medical examinations or perform treatment processes. These and other processes require the use of an optical probe (e.g., endoscope, catheter, etc.) inserted through a body cavity (e.g., blood vessel or bronchus) to reach the mechanical rotation of the target. In most of these applications, in order to provide a reasonable field of view, it is necessary to rotate the detection optical fiber. In order to provide continuous light transmission between the rotation detection optical fiber contained in the catheter, endoscope, etc. and the fixed system containing a light source and a light detector, a special unit conventionally referred to as a fiber optic rotary joint (Fiber Optic Rotary Joint) (FORJ, rotary joint or rotary joint) is generally used. FORJ must improve mechanical actuation and optical connection between the optical probe and the operating console. Optical connection allows the optical system to be communicated with the rotating distal end of the probe, and mechanical connection allows the optical probe to rotate or oscillate to scan the body cavity. In order to reduce the positional accuracy requirements at FORJ, some beam expansion components (such as, collimators) are generally used for beam transmission in the gap between the fixed optical fiber and the rotating optical fiber. In some applications, the FORJ also includes a translation stage for mechanically displacing the optical probe in the longitudinal direction along the inner cavity. To reduce the positional accuracy requirements at the FORJ, some beam expansion components (such as collimators) are usually used for beam transmission in the gap between the fixed optical fiber and the rotating optical fiber.

[0003] Fiber optic rotary joint can be realized in various ways. However, no matter how to realize the rotary joint, a motor (e.g., a DC motor, a stepper motor, etc.) is needed to drive the rotation of the optical probe. The motor and other mechanical, optical and electronic components of the rotary joint are enclosed in a patient interface module or a patient interface unit (PIU). An example of a rotary joint is described in U.S. Patent 7,382,949. In addition, U.S. Patents 9,360,630 and 9,345,398 describe more examples of known drive assemblies for rotary joints. For all purposes, these and other U.S. patents and patent applications are publicly incorporated herein by reference.

[0004] Conventional rotary joints of the type described in the above referenced patents tend to use large, bulky and expensive components, which causes the efficiency of the entire system to be lower than desired. For example, the rotary joints described in U.S. Patents 7382949 and 9345398 use a rotary motor that drives the rotating part of the FORJ through a synchronous belt or gear. This results in a mechanically complex unit with a large number of components and increased mechanical vibration. The FORJ disclosed in U.S. Patent 9360630 uses a hollow shaft motor that transmits an optical signal from a fixed collimator to a rotating collimator through a hollow shaft. In this patent, the relatively large gap (distance) between the two collimators makes the FORJ very sensitive to component misalignment and mechanical vibration. In addition, having a rotating collimator on a disposable catheter makes the disposable part of the system more expensive.

[0005] Therefore, there remains a need for improved fiber optic rotary joints suitable for use in medical probes such as endoscopes, catheters, and the like. Summary of the invention

[0006] According to at least one aspect, the present disclosure relates to a fiber optic rotary joint (FORJ) that connects a system console to a probe having a rotatable core and transmits rotational motion to the probe core. The FORJ includes a fixed optical fiber in optical communication with the rotatable optical fiber, a motor having a hollow shaft, and a fiber optic connector attached to the distal end of the hollow shaft. The motor is configured to rotate the rotatable optical fiber relative to the fixed optical fiber. The rotatable optical fiber is attached to the proximal end of the hollow shaft and connected to the fiber optic connector. The distal end of the fixed optical fiber is directly opposite to the proximal end of the rotatable optical fiber and is aligned with the proximal end of the rotatable optical fiber, so that the optical axis of the fixed optical fiber and the optical axis of the rotatable optical fiber are substantially colinear with the rotation axis of the motor. The fiber optic connector transmits optical power and torque to the probe core.

[0007] According to another aspect, the present disclosure is directed to a method of providing optical communication between a system console and a probe having a rotatable probe core and imparting rotational motion on the probe core. The method includes: arranging a first optical system having a fixed optical fiber that communicates with a system console, the fixed optical fiber having a distal end; arranging a second optical system, the second optical system including a rotatable optical fiber relative to the first optical system, the rotatable optical fiber having a proximal end and a distal end; providing a motor, the motor including a hollow shaft spanning from the proximal end to the distal end along the rotation axis of the motor; and attaching a fiber optic connector to the distal end of the hollow shaft, the fiber optic connector being suitable for connecting to a rotatable probe core; wherein the rotatable optical fiber is attached to the proximal end of the hollow shaft and connected to the fiber optic connector at the distal end of the hollow shaft, wherein the distal end of the fixed optical fiber is arranged directly opposite to the proximal end of the rotatable optical fiber and is aligned with the proximal end of the rotatable optical fiber with a gap therebetween, so that the optical axes of the fixed optical fiber and the rotatable optical fiber are substantially colinear with the rotation axis of the motor, and wherein imparting rotational motion to the probe core includes rotating the rotatable optical fiber around the rotation axis using the motor, and transmitting the rotational motion to the probe core via the fiber optic connector.

[0008] These and other aspects, features and advantages of the present disclosure will become apparent when the following detailed description of illustrative embodiments thereof is read in conjunction with the accompanying drawings and the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Other objects, features and advantages of the present disclosure will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate exemplary embodiments of the present disclosure.

[0010] Figure 1 A perspective view of a fiber optic rotary joint according to one embodiment of the present disclosure is shown.

[0011] Figure 2 A cross-sectional view of a fiber optic rotary joint according to an embodiment of the present disclosure is shown.

[0012] Figure 3A and Figure 3B A perspective view of FORJ is shown to explain the process of aligning the optical axis Ox2 of the optical fiber assembly 20 with the rotation axis Rx of the motor.

[0013] Figure 4 An exemplary system in which a fiber optic rotary joint according to the present disclosure is incorporated is illustrated. DETAILED DESCRIPTION

[0014] Before describing various embodiments in further detail, it is to be understood that the present disclosure is not limited to any particular embodiments. It is also to be understood that the terminology used herein is for the purpose of describing exemplary embodiments only and is not intended to be limiting.

[0015] Throughout the drawings, unless otherwise indicated, the same reference numerals and characters are used to represent similar features, elements, components or parts of the illustrated embodiments. In addition, although the subject disclosure is described in detail with reference to the drawings, it is a description in conjunction with illustrative exemplary embodiments. It is intended that the described exemplary embodiments be changed and modified without departing from the true scope of the subject disclosure as defined in the appended claims. Although the drawings represent some possible configurations and methods, the drawings are not necessarily drawn to scale and certain features may be exaggerated, removed or partially cut to better illustrate and explain certain aspects of the present disclosure. The description set forth herein is not intended to be exclusive or to limit or constrain the claims to the precise form and configuration shown in the drawings and disclosed in the following detailed description.

[0016] Those skilled in the art will recognize that, in general, the terms used herein, particularly in the appended claims (e.g., the bodies of the appended claims), are generally intended to be "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "including but not limited to," etc.). Those skilled in the art will further understand that if a specific number of an introduced claim recitation is intended, such intent will be expressly recited in the claim, and in the absence of such recitation, such intent is not present. For example, to aid understanding, the following appended claims may contain the use of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, even when the same claim includes the introductory phrases "one or more" or "at least one" and an indefinite article such as "a" or "an", the use of these phrases should not be interpreted as implying that a claim recitation introduced by the indefinite article "a" or "an" limits any particular claim containing such introduced claim recitation to claims containing only one such recitation (e.g., "a" and / or "an" should generally be interpreted as meaning "at least one" and "one or more"); the same is true for the use of definite articles used to introduce claim recitations.

[0017] In addition, even if a specific number of introduced claim records is explicitly recorded, those skilled in the art will recognize that such records should generally be interpreted as referring to at least the number recorded (for example, the pure record "two records" without other modifications generally refers to at least two records, or two or more records). In addition, in those cases where a convention similar to "at least one of A, B, and C, etc." is used, generally, such a construction is intended to have a convention that those skilled in the art will understand (for example, "a system having at least one of A, B, and C" will include but is not limited to systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Those skilled in the art will further understand that, generally, transitional words and / or phrases representing two or more alternative terms should be understood to contemplate the possibility of including one of the terms, any one of the terms, or both of the terms, whether in the specification, claims, or drawings, unless the context otherwise dictates. For example, the phrase "A or B" will generally be understood to include the possibility of "A" or "B" or "A and B".

[0018] When a feature or element is referred to herein as "on" another feature or element, it can be directly on other features or elements or there can also be intermediate features and / or elements. In contrast, when a feature or element is referred to as "directly on" another feature or element, there are no intermediate features or elements. It will also be understood that when a feature or element is referred to as being "connected," "attached," "coupled," etc. to another feature or element, it can be directly connected, attached or coupled to other features or elements, or there can be intermediate features or elements. In contrast, when a feature or element is referred to as being "directly connected," "directly attached," or "directly coupled" to another feature or element, there are no intermediate features or elements. Although described or illustrated with respect to one embodiment, the features and elements so described or illustrated in one embodiment can be applied to other embodiments. It will also be understood by those skilled in the art that the structure or feature referred to as being "adjacent" to another feature can have a portion overlapping or located below the adjacent feature.

[0019] The terms first, second, third, etc. can be used herein to describe various elements, components, regions, parts and / or segments. It should be understood that these elements, components, regions, parts and / or segments are not limited by these naming terms. These naming terms are only used to distinguish an element, component, region, part or segment from another region, part or segment. Therefore, the first element, component, region, part or segment discussed below can be referred to as the second element, component, region, part or segment only for the purpose of distinguishing, but not for limiting and not departing from the structure or function meaning.

[0020] As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that when used in this specification and claims, the terms "comprises" and / or variations thereof, "includes" and / or variations thereof, "consisting of" and / or variations thereof indicate the presence of the features, integers, steps, operations, elements, and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or groups thereof that are not explicitly stated. In addition, in the present disclosure, the conjunction "consisting of" does not include any element, step, or component not specified in the claim. It is also noted that some claims or some features in the claims may be drafted to exclude any optional elements; such claims may use exclusive terms related to the recording of the claim elements, such as "only", "only", etc., or may use a "negative" limitation to explicitly exclude features or steps or components.

[0021] As used herein, the term "about" or "approximately" refers to, for example, within 10%, within 5% or less. In some embodiments, the term "about" may refer to within a measurement error. In this regard, in the case of description or claim protection, even if the term does not appear explicitly, all numbers may be interpreted as starting with the word "about" or "approximately". When describing size and / or position, the phrase "about" or "approximately" may be used to indicate that the value and / or position described are within the reasonable expected range of the value and / or position. For example, a numerical value may have a value of + / -0.1% of the value (or range of values), + / -1% of the value (or range of values), + / -2% of the value (or range of values), + / -5% of the value (or range of values), + / -10% of the value (or range of values), etc. Unless otherwise expressly stated, any numerical range is intended to include end values ​​and include all sub-ranges contained herein when stated herein. As used herein, the term "substantially" means allowing deviations from the descriptor, which deviations do not have a negative impact on the intended purpose. For example, deviations relative to measurement limits, differences within manufacturing tolerances, or variations of less than 5% may be considered to be within the substantially same range. The designated descriptors may be absolute values ​​(e.g., substantially spherical, substantially perpendicular, substantially concentric, etc.) or relative terms (e.g., substantially similar, substantially identical, etc.).

[0022] Unless otherwise clearly specifically set forth from the following disclosure, it is understood that throughout the disclosure, discussions using terms such as "processing," "computing," "calculating," "determining," "displaying," and the like refer to the actions and processes of a computer system or similar electronic computing device or data processing device that manipulates data represented as physical (electronic) quantities within the registers and memories of the computer system and transforms it into other data similarly represented as physical quantities within the computer system memory or registers or other such information storage, transmission, or display devices. Unless the context otherwise dictates, the computer or electronic operations described in the specification or recited in the appended claims may generally be performed in any order. In addition, although various operational flow charts are presented in one (or more) sequences, it should be understood that various operations may be performed in other orders than those illustrated or claimed, or operations may be performed simultaneously. Unless the context otherwise dictates, examples of such alternative orderings may include overlapping, interleaved, interrupted, reordered, incremental, preparatory, complementary, simultaneous, reversed, or other variant orderings. Moreover, terms like "responsive to," "in response to," "related to," "based on," or other similar past tense adjectives are generally not intended to exclude such variations unless the context dictates otherwise.

[0023] The present disclosure generally relates to medical devices, and the present disclosure illustrates embodiments of optical probes that can be suitable for use in spectroscopy devices (e.g., endoscopes), optical coherence tomography (OCT) devices, or combinations of such devices (e.g., multimodal optical probes). Embodiments of optical probes and portions thereof are described in terms of their states in three-dimensional space. As used herein, the term "position" refers to the position of an object or a portion of an object in three-dimensional space (e.g., three translational degrees of freedom along Cartesian X, Y, and Z coordinates); the term "orientation" refers to the rotational arrangement of an object or a portion of an object (three rotational degrees of freedom - e.g., roll, pitch, and yaw); the term "pose" refers to the position of an object or a portion of an object in at least one translational degree of freedom and the orientation of the object or a portion of an object in at least one rotational degree of freedom (up to a total of six degrees of freedom); the term "shape" refers to a collection of poses, positions, and / or orientations measured along the elongated body of an object.

[0024] As is known in the medical device field, the terms "proximal" and "distal" are used in reference to the manipulation of the end of the instrument extending from the user to the surgical or diagnostic site. In this regard, the term "proximal" refers to the portion of the instrument that is closer to the user (e.g., the handle), and the term "distal" refers to the portion of the instrument that is farther from the user and closer to the surgical or diagnostic target site (the top). It will be further understood that for convenience and clarity, spatial terms such as "vertical", "horizontal", "upper", and "lower" may be used herein with respect to the accompanying drawings. However, imaging and / or surgical instruments are used in many orientations and positions, and these terms are not intended to be restrictive and / or absolute.

[0025] As used herein, the term "catheter" generally refers to a flexible, thin, tubular instrument made of medical grade material that is designed to be inserted into a body cavity (e.g., a blood vessel) through a narrow opening to perform a wide range of medical functions. The more specific term "optical catheter" refers to a medical instrument that includes an elongated bundle of one or more flexible optical fibers deployed inside a protective sheath made of medical grade material and has optical imaging capabilities. A specific example of an optical catheter is a fiber optic catheter that includes a sheath, a coil, a protector, and an optical probe. In some applications, the catheter may include a "guide catheter" that functions similarly to a sheath.

[0026] In the present disclosure, the term "light-conducting fiber", "optical fiber" or just "optical fiber" refers to an elongated, flexible light-conducting conduit (waveguide) that is capable of conducting light from one end to another due to an effect known as total internal reflection. The term "light-conducting component" or "waveguide" or "light pipe" may also refer to an optical fiber, or may have the functionality of an optical fiber. The term "optical fiber" may refer to one or more light-conducting fibers. An optical fiber has a generally transparent homogeneous core through which light is guided, and the core is surrounded by a homogeneous cladding or multiple claddings. The refractive index of the core is greater than the refractive index of the cladding or multiple claddings.

[0027] The following disclosure relates to a novel fiber optic rotary joint (FORJ) suitable for use in medical imaging systems using intraluminal optical probes such as endoscopes, catheters, and the like.

[0028] <Fiber Optic Rotary Joint>

[0029] Figure 1 A perspective view of a fiber optic rotary joint 100 according to an embodiment of the present disclosure is shown, and Figure 2A cross-sectional view thereof is shown. According to this embodiment, the rotary joint 100 includes a motor unit 10, an optical fiber assembly 20, and a fixing unit 30. The motor unit 10, the optical fiber assembly 20, and the fixing unit 30 are joined together in a manner that allows them to move relative to each other in the X-direction and the Y-direction for optical alignment purposes and then locks the alignment while maintaining a free space or gap 38 between the optical fiber assembly 20 and the fixing unit 30. Figure 1 and Figure 2 In the figure, the X-axis, Y-axis, and Z-axis are perpendicular to each other, the X direction is perpendicular to the plane of the figure, and the Y direction is perpendicular to the X (in Figure 2 in the plane of the figure, perpendicular to the plane of the figure), and the Z direction is parallel to the plane of the figure (in Figure 2 plane, horizontal).

[0030] The fixed unit 30 is in optical communication with the system console 01 via an optical fiber 36. The system console 01 includes a light source and a light detector not shown in the figure, as well as other components. Depending on the application or applications of the imaging system, the light source and the light detector not shown in the figure can be implemented in any known manner. In some embodiments, the imaging system may include an optical coherence tomography (OCT) imaging system. In this case, the system may use a swept source laser (wavelength 1310nm+ / -50nm) as an OCT light source, and the light detector may include a balanced photodetector including a photomultiplier tube (PMT), a photodiode, an avalanche photodiode detector (APD), a charge coupled device (CCD), a multi-pixel photon counter (MPPC) or a combination thereof. The optical fiber 36 is terminated with a ferrule 34 and a collimating lens 32 in the fixed unit 30. The collimating lens 32 expands the light beam transmitted by the optical fiber 36 and projects the expanded light beam toward the motor unit 10 along the optical axis Ox1. The direction of the optical axis Ox1 of the fixing unit 30 may be adjusted relative to the base 31 of the fixing unit 30 by one or more alignment screws 35 disposed on the adjustable stage 33 .

[0031] The motor unit 10 includes a motor 14 having a hollow shaft 15 having a rotation axis Rx. The motor unit 10 is mounted on a motor base 11. A rotating fiber optic assembly 20 is arranged inside the inner cavity of the hollow shaft 15 of the motor. The fiber optic assembly 20 includes an optical fiber 21 that spans from the proximal end to the distal end along the optical axis Ox2. The optical fiber 21 passes through a sleeve 22 and a rotating collimating lens 24 at the proximal end and is terminated by a standard LC type fiber optic connector 27 with a standard LC type adapter 18 on the distal end. The proximal end of the fiber optic assembly 20 is arranged inside a collimator housing 16, which is rigidly attached to the proximal end of the shaft 15 of the motor. The collimator housing 16 is a hollow tubular body that can be glued, clamped to the hollow shaft 15, or even integrally enclosed in the hollow shaft 15. That is, in some embodiments, the collimator housing 16 can be an integral part of the hollow shaft 15 (e.g., a protruding extension). The collimator housing 16 includes a plurality of fine adjustment screws 28 (four in one embodiment) supported by four opposing biasing springs 26 that allow alignment of the optical axis Ox2 of the fiber optic assembly 20 with the rotational axis Rx of the motor unit 10 .

[0032] At the distal end of the motor unit 10, an LC connector hub 12 is rigidly attached to the distal end of the motor's shaft 15 by a clamp 13. An LC adapter 18 is securely held inside the LC connector hub 12 by a plurality of fixing screws 19 (four in one embodiment). The LC adapter 18 has a rectangular shape that allows for secure engagement with the connector hub 12 and easy torque transmission from the motor's shaft 15 to the adapter 18. In this way, the adapter 18 can transmit rotational motion to the fiber optic connector 42 to rotate or oscillate the probe core 40 as indicated by arrow R.

[0033] Here, standard LC fiber optic connectors and LC adapters are mentioned as examples of fiber optic connection components that are easy to insert or remove while providing a secure and precisely aligned fit that complies with the TIA / EIA 604 standard. However, other types of standard fiber optic connection components such as SC, FC, and ST connectors may be used in a similar manner. The optical fiber 21 used in the rotating fiber optic assembly 20 and the optical fiber 36 used in the fixed fiber optic assembly 30 may be selected from single-mode optical fibers, double-clad optical fibers, or multimode optical fibers.

[0034] <Alignment of Motor Rotation Axis Rx and Optical Axis Ox2 of Fiber Optic Component>

[0035] The optical alignment of the FORJ will ensure reliable optical communication between the rotatable fiber optic assembly 20 held by the motor unit 10 and the fixed unit 30 through the air gap 38 formed between the collimator lens 32 and the collimator lens 24. In one embodiment, the air gap 38 can be in the range of about 1.0 mm to 10.0 mm. This is a significant reduction in gap size compared to conventional rotary joints where the air gap typically must additionally include the length of the hollow shaft of the motor. In some embodiments, the gap 38 formed between the collimator lens 32 and the collimator lens 24 can be filled with an optical coupling fluid (e.g., a liquid, gel, or gas) to enhance optical transmission therebetween.

[0036] The optical alignment of the non-rotating component, the rotatable optical fiber assembly and the motor unit 10 can be achieved in a known manner as known to those of ordinary skill in the art. For example, the entire optical alignment may include multiple steps. In the first step, the optical axis Ox2 of the optical fiber assembly 20 is aligned to coincide with the rotation axis Rx of the motor unit 10. More specifically, the optical axis Ox2 of the optical fiber assembly 20 arranged in the inner cavity of the hollow shaft 15 should be aligned with the rotation axis Rx of the motor 14. In the second step, the optical axis Ox1 of the optical component in the fixed unit 30 is at the same angle as the rotation axis Rx of the aligned motor unit 10. In this step, by operating one or more alignment screws 35, the optical axis Ox1 of the non-rotating optical component in the fixed unit 30 should be aligned substantially to coincide with the Z-axis direction. After these two steps, the two optical axes of the two optical components (fixed unit 30 and motor unit 10) are aligned to be parallel to each other. Therefore, only horizontal and vertical translation alignments need to be performed. This is performed in the third step. In the third step, the collimator 32 and the collimator 24 are made to face each other directly to allow only sliding movement between them in the X direction and the Y direction. Thereafter, the sliding movement between the facing surfaces of the collimator 32 and the collimator 24 is performed until the optical axis Ox1 of the fixing unit 30, the optical axis Ox2 of the optical fiber assembly 20, and the rotation axis Rx of the motor unit 30 are substantially collinear. As used herein, the term "collinear" is given its ordinary geometric meaning, whereby if three or more points are located on a single straight line, they are said to be collinear. At the end of the third step, the entire optical alignment of the FORJ assembly 100 is completed. The detailed process of this type of optical alignment is described in the inventor's previously disclosed U.S. Patent No.: 10558001A1, which is incorporated herein by reference for all purposes.

[0037] Figure 3A and Figure 3B A perspective view of FORJ is shown to explain the process of aligning the optical axis Ox2 of the optical fiber assembly 20 with the rotation axis Rx of the motor. Figure 3AThe state of the optical axis Ox2 of the optical fiber assembly 20 relative to the rotation axis Rx of the motor unit 10 before alignment is shown. In this step, the light beam 50 can be transmitted from the light source 51 through the optical fiber connector 18. Before alignment, the light beam 50 is emitted at the proximal end of the optical fiber assembly 20 at an angle β relative to the rotation axis Rx of the motor. In order to align the optical axis Ox2 of the optical fiber assembly 20 with the rotation axis Rx of the motor unit 10, the user operates one or more fixing screws 28 until the light beam 50 coincides with the rotation axis Rx. Figure 3B The state where the optical axis Ox2 is aligned with the rotation axis Rx is shown. In the state where the light beam 50 is coincidentally aligned (colinear) with the rotation axis Rx, the user can safely attach the connector 42 of the imaging probe 40 to the rotary joint. In this way, the optical alignment of the fixed optical fiber and the rotatable optical fiber is performed once during assembly and does not need to be performed every time a new probe is attached.

[0038] The motor 14 should preferably include an encoder to facilitate alignment between the FORJ and the optical connector of the probe by providing a predetermined FORJ connector position when engaged and disengaged. Encoders are known to those of ordinary skill in the art. For the FORJ, the optical encoder can be a built-in encoder or an external encoder strategically arranged to provide a predetermined connector position when engaged and disengaged.

[0039] It should be noted that the rotating optical fiber disposed within the lumen of the hollow shaft 15 of the motor 14 acts only as a light guide and not as a free-space optical communication medium for collimating the light beam as in some prior art techniques. The implementation of the rotating optical fiber as a light guide alleviates the burden of critical alignment between the rotating optical fiber and the fixed optical fiber by requiring alignment only once for the non-disposable portion of the instrument while making each connection to the disposable probe non-critical in terms of optical alignment.

[0040] As will be appreciated by those skilled in the art, optical fibers use the effect of total internal reflection for light propagation, and modern optical fiber technology allows optical fibers to be bent or linearly deflected without any significant loss of light transmission between the two ends of the optical fiber. Therefore, in the present disclosure, for optimal coupling of light transmission, the optical fibers require precise alignment at the light entry and exit points; this is achieved by FIG. 3A to FIG. 3B On the other hand, free space optics relies on light propagating in straight lines and requires very precise alignment between the light entry and exit points. Therefore, adding a short span of optical fiber between the light entry and exit points of the hollow shaft of the motor advantageously reduces the alignment requirements and ensures essentially lossless optical transmission.

[0041] In operation, a catheter or other intraluminal instrument having a probe core 40 is connected to the LC connector 27 by inserting another standard LC connector 42 of the probe core into the LC adapter 18. In this way, the proximal end of the probe core 40 is optically connected to the distal end of the rotating fiber optic assembly 20. The use of a standard LC connector 42, which also has a square outer profile, ensures a simple and reliable mechanical connection to the LC adapter 18. In addition, the use of standard components (standard LC adapter 18 and LC connector 42) provides a proven reliable optical connection, as well as a simplified transmission of rotational motion between the FORJ and the probe core 40, without the need to actively confirm the optical alignment between the probe core 40 and the rotating fiber optic assembly 20.

[0042] <Exemplary Imaging System>

[0043] Figure 4 An exemplary system 300 in which the fiber optic rotary joint 100 according to the present disclosure is loaded is illustrated. According to one example, the FORJ 100 can be applied to a medical imaging system 300 including an imaging console 310 (system console) and a disposable or limited-use optical probe 340 (e.g., an endoscope or catheter). A patient interface unit (PIU) 320 connects the optical probe 340 to the imaging console 310 using a cable bundle 314. The imaging console 310 includes a computer cart 302 and one or more displays 304, among others. The computer cart 302 contains a system component 306, which includes at least one or more processors, one or more light sources (laser sources), and one or more light detectors, among others. The optical probe 340 can include, for example, a fiber-based catheter having a probe core 40. In an exemplary imaging process, the imaging system 300 uses the probe core 40 to obtain an image of an imaging sample 360 ​​such as a cardiovascular body cavity of a patient.

[0044] PIU 320 is the main interface between probe 340 and system console 310. PIU provides components for rotating and linearly translating the imaging core of the probe within the fixed outer sheath of the catheter. The console 310 and PIU 320 are connected by a cable bundle 314. The cable bundle 314 contains cables for transmitting power and for communication signaling and optical fibers (e.g., optical fibers 36) for light transmission. During operation of the imaging system 300, the entire PIU 320 is preferably covered with a sterile cloth and arranged on a bed or operating table. PIU 320 can provide a user interface for operating the imaging function of the probe from the sterile field by using an operable button 321; these buttons 321 can mirror other controls (e.g., a graphical user interface (GUI) shown in the display 304) provided on the system console 310.

[0045] PIU 320 may include a beam combiner, a fiber optic rotary joint (FORJ) 100, a motion mechanism including a linear stage, an electronic control board, control buttons and / or an LED panel. As shown, FORJ 100 is configured to receive connector 42 for probe 340 therein.

[0046] <Software-related disclosure>

[0047] At least some aspects of the exemplary embodiments described herein may be implemented by a computer of a system or device that reads out and executes computer executable instructions (e.g., one or more programs or executable codes) recorded on a storage medium (which may also be referred to as a "non-transitory computer-readable storage medium") to perform the functions of one or more of the above-mentioned block diagrams or flowcharts. The computer may include various components known to those of ordinary skill in the art. For example, the computer may include a signal processor implemented by one or more circuits (e.g., a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC)) that perform the functions of one or more of the above-mentioned embodiments by, for example, reading out and executing computer executable instructions from a storage medium to perform the functions of one or more of the above-mentioned embodiments and / or controlling one or more circuits to perform the functions of one or more of the above-mentioned embodiments. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessing unit (MPU)), and may include a network of separate computers or separate processors for reading out and executing computer executable instructions. Computer executable instructions may be provided to the computer, for example, from a cloud-based network or from a storage medium. The storage medium may include, for example, a hard disk, a random access memory (RAM), a read-only memory (ROM), a memory of a distributed computing system, an optical disk (such as a compact disk (CD), a digital versatile disk (DVD), a Blu-ray disk (BD) TM ), flash memory devices, memory cards, etc. The computer may include an input / output (I / O) interface to receive communication signals (data) and / or send communication signals (data) to input devices and output devices, which may include a keyboard, a display, a mouse, a touch screen, a touchless interface (e.g., a gesture recognition device), a printing device, a light pen, an optical storage device, a scanner, a microphone, a camera, a drive, a communication cable, and a network (wired or wireless).

[0048] The novel FORJ disclosed herein provides several technical advantages over conventional rotary joints known in the prior art, including but not limited to:

[0049] Shorter air gap distance between rotating and fixed parts of FORJ. This is compared to the prior art which uses a hollow shaft motor bore as a free space medium for beam propagation. In this case, the light should travel through the entire length of the shaft in air or other medium (free space optical communication), thereby increasing the air gap length;

[0050] Low-cost and reliable standard probe / catheter core connection. In this regard, for example, it is noted that the standard fiber optic adapter 18 having a fiber optic connector 42 configured to receive the probe alleviates the need for alignment during connection and removal of the probe;

[0051] Lower parts count, resulting in lower cost and higher reliability;

[0052] Lower design and assembly complexity. For example, optical alignment of the fixed optical fiber and the rotatable optical fiber is performed once during assembly and does not need to be done every time a new probe is attached.

[0053] Smaller mechanical vibration effect.

[0054] <Other embodiments or modifications>

[0055] With reference to the description, specific details are set forth to provide a thorough understanding of the disclosed examples. In other cases, known methods, processes, components, and circuits are not described in detail so as not to unnecessarily lengthen the disclosure. Unless otherwise defined herein, all technical and scientific terms used herein have the same meaning as those generally understood by those of ordinary skill in the art to which the disclosure belongs. In this regard, the breadth and scope of the disclosure are not limited by the specification or drawings, but only by the plain meaning of the claimed terms adopted.

[0056] In describing the example embodiments illustrated in the accompanying drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner. Therefore, the scope of the appended claims will be given the broadest interpretation to encompass all such variations and equivalent structures and functions.

Claims

1. An optical fiber rotary joint for providing optical communication between a fixed system and a probe having a rotatable probe core and imparting rotational motion on the probe core, the optical fiber rotary joint comprising: a fixed unit including a fixed fiber optic assembly in communication with the fixed system, the fixed fiber optic assembly having a distal end; a motor unit comprising a hollow shaft motor having a hollow shaft with a lumen spanning from a proximal end to a distal end along a rotation axis Z of the hollow shaft motor; the motor unit and the fixed unit are joined together in a manner that will allow them to move relative to each other in the X direction and the Y direction, wherein X and Y are orthogonal to Z; and a rotatable fiber optic assembly having a proximal end and a distal end, the rotatable fiber optic assembly being disposed within the lumen of the hollow shaft along the axis of rotation of the hollow shaft motor and spanning between the proximal end and the distal end of the hollow shaft; in: The rotatable fiber optic assembly also includes a fiber optic connector attached to the distal end of the hollow shaft and adapted to connect to a mating connector of the probe core; A rotatable fiber optic assembly is attached to the proximal end of the hollow shaft; and The distal end of the fixed fiber optic assembly is spatially directly opposite the proximal end of the rotatable fiber optic assembly and is adapted to be in optical communication with the proximal end of the rotatable fiber optic assembly.

2. The optical fiber rotary joint according to claim 1, in, The rotatable fiber optic assembly also includes matching opposing collimator lenses at its proximal end and the fixed fiber optic assembly at its distal end.

3. The optical fiber rotary joint according to claim 2, in, Both the proximal end of the rotatable fiber optic assembly and the distal end of the fixed fiber optic assembly also include features suitable for optical alignment of the mating relative collimator lenses.

4. The optical fiber rotary joint according to claim 3, in, The features suitable for optical alignment are configured to move one or more of the rotatable fiber optic assembly and the fixed fiber optic assembly relative to each other until the optical axis of the fixed fiber optic assembly and the optical axis of the rotatable fiber optic assembly are substantially colinear with the rotational axis of the hollow shaft motor.

5. The optical fiber rotary joint according to claim 1, in, Both the proximal end of the rotatable fiber optic assembly and the distal end of the fixed fiber optic assembly are adapted for direct fiber-to-fiber optical transmission via a gap therebetween.

6. The optical fiber rotary joint according to claim 5, in, The gap establishes a distance of approximately 1.0 mm to 10.0 mm between the proximal end of the rotatable fiber optic assembly and the distal end of the fixed fiber optic assembly.

7. The optical fiber rotary joint according to claim 1, wherein: The motor unit and the fixing unit can be locked together after alignment to prevent relative movement in the X-direction and the Y-direction while maintaining a free space or gap between the optical fiber assembly and the fixing unit.

8. An apparatus for delivering a rotating light beam to a target within a lumen via a probe having a rotatable probe core, the apparatus comprising: A first optical system including a fixed optical fiber; a second optical system comprising a rotatable optical fiber having a proximal end and a distal end; a hollow shaft motor having a hollow shaft with a lumen spanning from a proximal end to a distal end along a rotational axis Z of the hollow shaft motor; The hollow shaft motor and the first optical system unit and the fixing unit are coupled together in a manner that will allow them to move relative to each other in the X direction and the Y direction, wherein X and Y are orthogonal to Z; as well as a fiber optic connector attached to the distal end of the hollow shaft, the fiber optic connector being adapted to be connected to the rotatable probe core; wherein a rotatable optical fiber is attached to the proximal end of the hollow shaft, is arranged through the inner cavity of the hollow shaft along the rotation axis of the hollow shaft motor, and is connected to a fiber optic connector at the distal end of the hollow shaft, wherein the distal end of the fixed optical fiber is directly opposite and aligned with the proximal end of the rotatable optical fiber such that the optical axes of the fixed optical fiber and the rotatable optical fiber are substantially co-linear with the axis of rotation of the hollow shaft motor, and Therein, the hollow shaft motor is configured to rotate the rotatable optical fiber around the rotation axis, and the optical fiber connector transmits the rotational motion to the probe core.

9. A method of providing optical communication between a system console and a probe having a rotatable probe core and imparting rotational motion on the probe core, the method comprising: arranging a first optical system having a fixed optical fiber in communication with a system console, the fixed optical fiber having a distal end; arranging a second optical system, the second optical system comprising an optical fiber rotatable relative to the first optical system, the rotatable optical fiber having a proximal end and a distal end; providing a hollow shaft motor having a hollow shaft with a lumen spanning from a proximal end to a distal end along a rotational axis Z of the hollow shaft motor; attaching a fiber optic connector to the distal end of the hollow shaft, the fiber optic connector being adapted to be connected to the rotatable probe core; as well as aligning the first optical system and the fixing unit in an X direction and / or a Y direction by moving the first optical system and / or the hollow shaft motor relative to each other, wherein X and Y are orthogonal to Z, wherein a rotatable optical fiber is attached to the proximal end of the hollow shaft, is arranged through the inner cavity of the hollow shaft along the rotation axis of the hollow shaft motor, and is connected to a fiber optic connector at the distal end of the hollow shaft, wherein the distal end of the fixed optical fiber is arranged directly opposite and aligned with the proximal end of the rotatable optical fiber with a gap therebetween so that the optical axes of the fixed optical fiber and the rotatable optical fiber are substantially colinear with the rotational axis of the hollow shaft motor, and The imparting of the rotational motion to the probe core includes rotating the rotatable optical fiber using a hollow shaft motor so that the rotatable optical fiber rotates around a rotation axis of the hollow shaft motor, and transmitting the rotational motion to the probe core via a fiber optic connector.

10. The method according to claim 9, further comprising: Features are provided for optical alignment of both rotatable and fixed fiber optic assemblies.

11. The method according to claim 10, further comprising: The features adapted for optical alignment are operated to move one or more of the rotatable fiber optic assembly and the fixed fiber optic assembly relative to each other until the optical axes of the fixed fiber optic assembly and the rotatable fiber optic assembly are substantially co-linear with the axis of rotation of the hollow shaft motor.

12. The method according to claim 9, further comprising: After aligning the first optical system unit and the fixing unit, the first optical system and the hollow shaft motor are locked together to prevent relative movement in the X-direction and the Y-direction.

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