Scanning system, endoscope and three-dimensional image construction method

Abstract

The invention relates to a scanning system, an endoscope and a three-dimensional image construction method. The scanning system comprises a light source, a light combining element, an ultrasonic transducer and a photoelectric detector; the light combining element is configured to be capable of transmitting at least part of light rays emitted by the light source to the ultrasonic transducer, and the ultrasonic transducer is configured to be capable of transmitting at least part of light rays transmitted to the ultrasonic transducer by the light combining element to a detected object; at least part of light returned to the ultrasonic transducer from the detected object can be transmitted to the light combining element; the light combining element is further configured to be capable of conducting at least part of light transmitted to the light combining element by the ultrasonic transducer to a photoelectric detector. According to the scanning system, optical signals and ultrasonic signals can be collected through one scanning system, different devices do not need to be replaced during detection, and the operation complexity, the operation examination duration and the discomfort degree of a patient can be reduced.

Description

Technical Field

[0001] This application relates to the field of optical scanning technology, and in particular to a scanning system, an endoscope, and a method for constructing three-dimensional images. Background Technology

[0002] When using endoscopy to diagnose or treat tissues within a patient's body, optical scanning devices are typically used to acquire cellular-level structural data, while photoacoustic scanning devices are used to acquire deep functional components. Combining these images allows for better early disease diagnosis, individualized development of minimally invasive treatment plans, and navigation and assessment during surgery. However, current scanning devices cannot simultaneously perform optical and photoacoustic scanning. During examination, it is usually necessary to switch between the two devices, increasing operational complexity, surgical examination time, and patient discomfort. Summary of the Invention

[0003] Therefore, it is necessary to provide a scanning system, endoscope, and three-dimensional image construction method to address the issues of increased operational complexity, longer surgical examination time, and patient discomfort caused by the replacement of optical scanning devices with photoacoustic scanning devices.

[0004] A scanning system includes a light source, a light combining element, an ultrasonic transducer, and a photodetector;

[0005] The light combining element is configured to conduct at least a portion of the light emitted by the light source to the ultrasonic transducer, and the ultrasonic transducer is configured to transmit at least a portion of the light transmitted from the light combining element to the ultrasonic transducer to the object being tested, and to transmit at least a portion of the light returning from the object being tested to the ultrasonic transducer to the light combining element.

[0006] The light combining element is also configured to conduct at least a portion of the light transmitted from the ultrasonic transducer to the light combining element to the photodetector.

[0007] In one embodiment, the light combining element includes a dichroic mirror, the light emission direction of the light source intersects with the light combining element, the photodetector is disposed on the side of the light combining element facing away from the ultrasonic transducer along the optical path, and the light combining element is capable of reflecting at least a portion of the light emitted by the light source and transmitting at least a portion of the light transmitted to the light combining element through the ultrasonic transducer.

[0008] In one embodiment, the scanning system further includes an objective lens assembly disposed along the optical path between the light combining element and the ultrasonic transducer, wherein at least one lens in the objective lens assembly is configured to be movable relative to the ultrasonic transducer in a direction parallel to the optical axis.

[0009] In one embodiment, the scanning system further includes a first light-blocking element and a second light-blocking element. The first light-blocking element is disposed along the optical path between the light source and the light-combining element and has a first light-transmitting hole. The second light-blocking element is disposed along the optical path between the light-combining element and the photodetector and has a second light-transmitting hole. The positions of the first light-blocking element and the second light-blocking element on the optical path are conjugate with respect to the object being detected.

[0010] In one embodiment, the light source includes a tunable laser source with a wavelength tuning range of 450nm-950nm.

[0011] In one embodiment, the scanning system includes a first observation mode and a second observation mode. In the first observation mode, the wavelength range emitted by the light source is 450nm-800nm, and in the second observation mode, the wavelength range emitted by the light source is 680nm-950nm.

[0012] In one embodiment, the scanning system further includes a planar beam scanner and a coherent fiber bundle disposed along the optical path between the planar beam scanner and the ultrasonic transducer. The coherent fiber bundle includes multiple optical fibers arranged side by side. The planar beam scanner is configured to selectively direct at least a portion of the light transmitted from the light combining element to the planar beam scanner into any one of the optical fibers in the coherent fiber bundle.

[0013] In one embodiment, the scanning system further includes a frame memory, a scan generator, and an objective lens assembly. The frame memory is communicatively connected to the photodetector and the ultrasonic transducer and is used to receive electrical signals generated by the photodetector and the ultrasonic transducer. The objective lens assembly is disposed between the beam combining element and the ultrasonic transducer. At least one lens in the objective lens assembly is configured to move relative to the ultrasonic transducer along a direction parallel to the optical axis. The scan generator is communicatively connected to the planar beam scanner, the drive mechanism of the objective lens assembly, and the frame memory, and is used to control the deflection of the planar beam scanner and the movement of at least one lens in the objective lens assembly, so that the electrical signals generated by the photodetector and the ultrasonic transducer at the same coordinate position on each focal plane correspond, and the electrical signals generated by the photodetector and the ultrasonic transducer at different coordinate positions on the same focal plane correspond.

[0014] An endoscope includes a main unit, a transmission component, an endoscope body, and a scanning system as described in any of the above embodiments. The transmission component is used to provide signal transmission between the main unit and the endoscope body. The light source, the light combining element, and the photodetector are disposed within the main unit, and the ultrasonic transducer is disposed within the endoscope body.

[0015] A method for constructing a 3D image, comprising:

[0016] The planar beam scanner, controlled by the scanning generator, transmits the light emitted by the light source sequentially through different fibers of the coherent fiber bundle onto the object being inspected.

[0017] The photodetector sequentially collects light rays emitted from the object being detected through different optical fibers;

[0018] The ultrasonic transducer sequentially collects ultrasonic signals emitted by the object under test corresponding to different positions of the optical fiber;

[0019] The electrical signals generated by the photodetector and the ultrasonic transducer are correlated with the coordinate positions of different optical fibers.

[0020] In one embodiment, the three-dimensional image construction method further includes:

[0021] The scanning generator controls the drive mechanism of the objective lens group to move at least one lens to correspond sequentially to different focal plane positions.

[0022] The planar beam scanner is controlled by a scanning generator to transmit the light emitted by the light source sequentially through different fibers of the coherent fiber bundle to the object being detected at each position corresponding to the focal plane.

[0023] The photodetector and the ultrasonic transducer sequentially collect light rays and ultrasonic signals corresponding to the coordinate positions of different optical fibers on each focal plane.

[0024] In the aforementioned scanning system, when it is necessary to obtain tissue cell-level structures, at least a portion of the light emitted by the light source can be transmitted to the ultrasonic transducer by the light combining element, and then irradiated onto the object being tested (such as tissue in a patient's body) through the ultrasonic transducer. After the light is reflected by the object being tested, or after the object being tested is excited to produce fluorescence, it is transmitted to the light combining element through the ultrasonic transducer, and then transmitted to the photodetector by the light combining element. The photodetector collects optical signals to obtain tissue cell-level structures.

[0025] When it is necessary to obtain deep functional components of tissue, at least part of the light emitted by the light source can be transmitted to the ultrasonic transducer by the light combining element, and then shine through the ultrasonic transducer onto the object being tested. The light excites the ultrasonic signal generated by the object being tested and returns to the ultrasonic transducer. The ultrasonic transducer collects the ultrasonic signal to obtain the deep functional components of tissue.

[0026] Thus, the aforementioned scanning system can acquire both optical and ultrasound signals, allowing for the acquisition of tissue cellular structure and deep functional components through a single system. This eliminates the need to change between different devices during examination, reducing operational complexity, surgical examination time, and patient discomfort. Furthermore, the scanning system utilizes a light-combining element and a transparent ultrasound transducer to achieve a high degree of integration between the optical and photoacoustic scanning devices. This allows the ultrasound transducer and photodetector to share a single light source, with overlapping optical paths, which helps to reduce the space occupied by the scanning system, thereby facilitating its assembly and use within endoscopes. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the scanning system in some embodiments.

[0028] Figure 2 for Figure 1 The diagram shows the structure of two scanning coordinate positions of the scanning system.

[0029] Figure 3 for Figure 1 The diagram shows the structure of two focal points of the scanning system.

[0030] Figure 4 for Figure 3 The diagram shows the structure of some components in the scanning system.

[0031] Figure label:

[0032] 10. Scanning system; 11. Light source; 12. Beam combiner; 13. Ultrasonic transducer; 14. Photodetector; 15. First light-blocking element; 151. First light-transmitting aperture; 16. Second light-blocking element; 161. Second light-transmitting aperture; 17. Planar beam scanner; 18. Coherent fiber bundle; 19. Objective lens group; 21. Drive mechanism; 22. Frame memory; 23. Scan generator; 24. Collimating lens group; 25. Field lens; 26. Focusing lens group; 27. Display screen; 30. Object under inspection. Detailed Implementation

[0033] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0034] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0035] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0036] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0037] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0038] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0039] Please see Figure 1 , Figure 1 The accompanying drawings are schematic diagrams of the scanning system 10 provided in some embodiments of this application. Dashed lines in the drawings indicate the optical path between the components. The scanning system 10 provided in this application includes, but is not limited to, use in endoscopes. When a portion of the endoscope is inserted into the patient's body, the scanning system 10 can collect light reflected from the patient's tissue or fluorescence emitted by stimulated emission, and ultrasound signals generated by the patient's tissue, thereby obtaining the cellular structure and deep functional components of the patient's tissue, enabling better early disease diagnosis, individualized formulation of minimally invasive treatment plans, and navigation and evaluation during surgery.

[0040] In some embodiments, the scanning system 10 includes a light source 11, a light combining element 12, an ultrasonic transducer 13, and a photodetector 14. The light source 11 emits light toward the light combining element 12, and the light combining element 12 is configured to conduct at least a portion of the light emitted by the light source 11 to the ultrasonic transducer 13. At least a portion of the ultrasonic transducer 13 is made of a light-transmitting material, such that the ultrasonic transducer 13 can transmit at least a portion of the light transmitted from the light combining element 12 to the object under test 30, and can transmit at least a portion of the light emitted from the object under test 30 to the ultrasonic transducer 13 back to the light combining element 12. The light combining element 12 is also configured to conduct at least a portion of the light transmitted from the ultrasonic transducer 13 to the light combining element 12 to the photodetector 14.

[0041] In this application, the photodetector 14 includes, but is not limited to, any suitable element capable of converting optical signals into electrical signals, such as a photomultiplier tube (PMT), an avalanche photodiode (APD), a single-photon avalanche diode (SPAD), a charge-coupled device (CCD), or a complementary metal-oxide-semiconductor (CMOS).

[0042] It is understood that, since the scanning system 10 integrates a photodetector 14 and an ultrasonic transducer 13, the scanning system 10 can be considered to have two scanning modes, referred to in this application as the first observation mode and the second observation mode. In the first observation mode, at least a portion of the light emitted by the light source 11 can be transmitted to the ultrasonic transducer 13 by the light combining element 12, and then irradiated onto the object under test 30 (such as tissue in a patient's body) through the ultrasonic transducer 13. After the light is reflected by the object under test 30, or after the object under test 30 is excited to produce fluorescence, it is transmitted to the light combining element 12 through the ultrasonic transducer 13, and then transmitted to the photodetector 14 by the light combining element 12. The photodetector 14 can receive the optical signal from the object under test 30 to obtain the cellular structure of the object under test 30.

[0043] In the second observation mode, at least a portion of the light emitted by the light source 11 can be transmitted to the ultrasonic transducer 13 by the light combining element 12, and then transmitted to the object under test 30 through the ultrasonic transducer 13. The light excites the object under test 30 to generate an ultrasonic signal (such as ultrasound). The ultrasonic signal returns to the ultrasonic transducer 13, and the ultrasonic transducer 13 can collect the ultrasonic signal from the object under test 30 to obtain the deep functional components of the object under test 30.

[0044] With this configuration, the aforementioned scanning system 10 can acquire both optical and ultrasonic signals. A single scanning system 10 can obtain tissue cell-level structures and deep functional components. Integrating the optical and photoacoustic scanning devices eliminates the need to change devices during examination, reducing operational complexity, surgical examination time, and patient discomfort. The scanning system 10 also employs a light-combining element 12 and a transparent ultrasonic transducer 13 to achieve a high degree of integration between the optical and photoacoustic scanning devices. This allows the ultrasonic transducer 13 and the photodetector 14 to share a single light source 11, with overlapping optical paths. This reduces the space occupied by the scanning system 10, thus facilitating its assembly and use within the endoscope.

[0045] In this application, the structure and type of the ultrasonic transducer 13 are not limited, as long as the ultrasonic transducer 13 can meet the requirements of light transmission performance and ultrasonic signal acquisition. For example, the ultrasonic transducer 13 includes, but is not limited to, a piezoelectric ceramic-based transparent transducer, a polymer-based transparent transducer, or a transparent piezoelectric single-crystal transducer. When using a piezoelectric ceramic-based transparent transducer, the piezoelectric material can be doped and modified lead zirconate titanate (PZT) to optimize the balance between light transmission and piezoelectric performance. When using a polymer-based transparent transducer, PVDF-TrFE copolymers can be used to balance flexibility and light transmission. When using a transparent piezoelectric single-crystal transducer, relaxor ferroelectric single crystals can be used to balance light transmission and ultrasonic response speed.

[0046] In some embodiments, the light source 11 and the photodetector 14 are disposed on opposite sides of the light combining element 12. The light combining element 12 can reflect one of the light emitted by the light source 11 and the light transmitted to the light combining element 12 by the ultrasonic transducer 13, and can transmit the other of the light emitted by the light source 11 and the light transmitted to the light combining element 12 by the ultrasonic transducer 13. The light combining element 12 can be any suitable element capable of reflecting and transmitting part of the light, such as a light combining prism or a dichroic mirror. With this configuration, the light combining element 12 can highly integrate the illumination light path and the detection light path by means of transmission and reflection, thereby reducing the space occupied by the scanning system 10 while taking into account both optical scanning and photoacoustic scanning.

[0047] Furthermore, in some embodiments, the light combining element 12 is a dichroic mirror, and the light emission direction of the light source 11 intersects with the light combining element 12. For example, the angle between the light emission direction of the principal ray of the light source 11 and the surface of the light combining element 12 facing the light source 11 is 45°. A photodetector 14 is disposed on the side of the light combining element 12 facing away from the ultrasonic transducer 13 along the optical path. The photodetector 14 and the light source 11 can be disposed on opposite sides of the light combining element 12, and the axis of the photodetector 14 can form a 45° angle with the surface of the light combining element 12 facing the photodetector 14. The light combining element 12 can reflect at least a portion of the light emitted by the light source 11 and transmit at least a portion of the light transmitted to the light combining element 12 through the ultrasonic transducer 13.

[0048] Understandably, the light intensity emitted by the light source 11 is usually much greater than the light intensity of the fluorescence reflected or excited by the object being detected 30. For example, the light intensity from the object being detected 30 may only be one millionth of the light intensity emitted by the light source 11, while the transmittance of a dichroic mirror is usually greater than its reflectance. Therefore, by transmitting the weaker light from the object being detected 30 through the dichroic mirror and reflecting the stronger light from the light source 11, it is beneficial to reduce photon loss, increase the intensity of the light collected by the photodetector 14, and improve detection accuracy. At the same time, it can also isolate the outgoing light path of the light source 11 from the receiving light path of the photodetector 14, forming an optical barrier to prevent the light emitted by the light source 11 from directly hitting the photodetector 14 without passing through the object being detected 30. This helps to suppress background stray light of the photodetector 14, avoid the risk of strong light causing saturation or even damage to the photodetector 14, improve the signal-to-noise ratio of the optical signal collected by the photodetector 14, and improve detection accuracy.

[0049] In some embodiments, the scanning system 10 further includes a first light-blocking element 15 and a second light-blocking element 16. The first light-blocking element 15 is disposed along the optical path between the light source 11 and the light-combining element 12, and has a first light-transmitting hole 151. The second light-blocking element 16 is disposed along the optical path between the light-combining element 12 and the photodetector 14, and has a second light-transmitting hole 161. The positions of the first light-blocking element 15 and the second light-blocking element 16 on the optical path are conjugate with respect to the object being detected 30. The first light-transmitting hole 151 and the second light-transmitting hole 161 form two conjugate pinholes, enabling the second light-transmitting hole 161 to effectively filter out light rays from the object being detected 30 other than the focal plane, thereby achieving confocal imaging of optical scanning, improving the signal-to-noise ratio of the optical signal received by the photodetector 14, and improving scanning accuracy. Both the first light-blocking element 15 and the second light-blocking element 16 can be structures such as light-shielding plates with partially hollowed-out light-transmitting holes.

[0050] Combination Figure 1 and Figure 2 As shown, in some embodiments, the scanning system 10 further includes a planar beam scanner 17 and a coherent fiber bundle 18. The planar beam scanner 17 includes, but is not limited to, a micro-electro-mechanical systems (MEMS) scanning mirror or galvanometer. The planar beam scanner 17 is disposed along the optical path between the light combining element 12 and the ultrasonic transducer 13, and is used to adjust the exit position of the light from the light combining element 12 on a plane perpendicular to the optical axis after passing through the planar beam scanner 17, that is, to adjust the position of the light hitting the object 30 being inspected. The coherent fiber bundle 18 is disposed along the optical path between the planar beam scanner 17 and the ultrasonic transducer 13, and includes multiple optical fibers arranged side by side. Since the planar beam scanner 17 can adjust the exit position of the light on a plane perpendicular to the optical axis, the planar beam scanner 17 is configured to selectively direct at least a portion of the light transmitted from the light combining element 12 to the planar beam scanner 17 into any fiber of the coherent fiber bundle 18. With this configuration, the light emitted by the light source 11 at a certain moment can be controlled to hit a certain coordinate position of the object under test 30 through the cooperation of the planar beam scanner 17 and the coherent fiber bundle 18. This facilitates the photodetector 14 and the ultrasonic transducer 13 to sequentially collect signals from each coordinate position on a certain focal plane of the object under test 30, which is beneficial for the construction of two-dimensional image information on a certain focal plane.

[0051] Combination Figure 3 and Figure 4As shown, in some embodiments, the scanning system 10 further includes an objective lens assembly 19 disposed along the optical path between the light combining element 12 and the ultrasonic transducer 13. The objective lens assembly 19 includes one or more lenses with optical power. The objective lens assembly 19 is used to focus the light from the light combining element 12 onto the object under test 30, and also to converge and couple the light from the object under test 30 into the coherent fiber bundle 18. The specific arrangement of the lenses in the objective lens assembly 19 is not limited and can be designed according to the dimming requirements. The scanning system 10 also includes a drive mechanism 21, which is used to drive at least one lens in the objective lens assembly 19 to move relative to the ultrasonic transducer 13 along the direction parallel to the optical axis. The drive mechanism 21 includes, but is not limited to, any suitable structure capable of driving or pulling the lens movement, such as an ultrasonic motor, a stepper motor, a voice coil motor, a shape memory alloy, or a metal wire. Understandably, when at least one lens in the objective lens group 19 moves relative to the ultrasonic transducer 13 along the parallel optical axis, the focal length of the objective lens group 19 can be changed, thereby changing the focal plane of the scanning system 10. This allows the photodetector 14 and the ultrasonic transducer 13 to acquire information from different focal planes of the object under test 30. Combined with the planar beam scanner 17 and the coherent fiber bundle 18, information from the coordinates of various positions on different focal planes of the object under test 30 can be acquired sequentially. This facilitates the construction of three-dimensional image information of the object under test 30, enabling richer scanning functions and improving the accuracy of diagnosis and treatment. By controlling the axial position of the lens moved by the drive mechanism 21, rapid and precise switching of the optical focal plane can also be achieved, thus completing the axial scanning of the focused spot without moving the entire scanning system 10, improving response speed.

[0052] Figure 3 and Figure 4 The image shows two different positions where the drive mechanism moves one of the lenses, indicated by dashed lines and dashed lines. Two axially offset focal positions are indicated by dashed lines of two different line types.

[0053] It should be noted that the optical signal collected by the photodetector 14 can be light emitted by the light source 11 and reflected back by the object under test 30, or it can be fluorescence generated by the exogenous contrast agent or endogenous fluorescent substance of the object under test 30 excited by the light emitted by the light source 11.

[0054] In some embodiments, the light source 11 is a tunable laser source 11 with a wavelength tuning range of 450nm-950nm. With this configuration, the tuning wavelength range of the light source 11 includes visible light and near-infrared light, which can simultaneously support the imaging requirements of optical scanning fluorescence imaging and photoacoustic scanning, achieving the effect of dual-purpose source. The first observation mode and the second observation mode can be realized through one light source 11, which is beneficial to reducing the space occupied by the scanning system 10.

[0055] Of course, the wavelength tuning range of the light source 11 can be designed according to the detection wavelength and scanning probe corresponding to the first observation mode and the second observation mode. When the light collected in the first observation mode is not fluorescent but light emitted by the light source 11 and reflected by the object being detected 30, the wavelength tuning range of the light source 11 can also be adjusted accordingly, which is not limited in this application.

[0056] For example, when photodetector 14 collects fluorescence in the first observation mode, the wavelength range emitted by light source 11 can be a continuous wave or a high-repetition-rate pulsed laser in the range of 450nm-800nm. Further, when using the fluorescent probe FITC for labeling proteins and gene expression, the wavelength emitted by light source 11 can be 490nm. When using the fluorescent probe Cy5 for deep tissue imaging and multicolor labeling, the wavelength emitted by light source 11 can be 650nm. When using the near-infrared fluorescent probe ICG for angiography and tumor targeting, the wavelength emitted by light source 11 can be 780nm. With this configuration, light source 11 can meet the optimal fluorescence excitation wavelengths for various probes, which is beneficial for improving scanning results.

[0057] In the second observation mode, the wavelength range emitted by the light source 11 can be 680nm-950nm. The photoacoustic effect relies on light absorption; the laser pulse is absorbed by absorbers in the tissue, generating heat and instantaneous expansion, thereby exciting an ultrasonic signal. Hemoglobin in the blood (including oxyhemoglobin and deoxyhemoglobin) is one of the most important endogenous absorbers in the human body. Hemoglobin has a characteristic absorption spectrum in the 680nm-950nm band, which is also located in the first window of the near-infrared spectrum, where water absorption is relatively weak, resulting in better overall tissue penetration. In some embodiments, characteristic wavelengths such as 750nm (strong absorption by deoxyhemoglobin) and 850nm (strong absorption by oxyhemoglobin) can be selected, which is beneficial for directly calculating blood oxygen saturation and improving the photoacoustic imaging effect. Of course, when the second observation mode targets more than just hemoglobin, the wavelength tuning range of the light source 11 can be adjusted according to the scanning object. For example, in lipid photoacoustic imaging, the lipid core in atherosclerotic plaques has characteristic absorption peaks at 930nm, 1200nm, and 1700nm. Wavelengths above 1200nm can be used to characteristically stimulate lipids, thereby improving the accuracy and detection rate of cardiovascular diseases.

[0058] The tunable laser source 11 can continuously and precisely adjust its output wavelength within a specific wavelength range, enabling a single system to adapt to various fluorescent probes or endogenous chromophores. Multicolor fluorescence imaging can be achieved without hardware replacement, significantly broadening its application range. Simultaneously, during photoacoustic imaging, the operator can precisely and rapidly scan the excitation wavelength to obtain the photoacoustic responses of different absorbers (such as oxy / deoxyhemoglobin, lipids, and exogenous contrast agents) at different wavelengths. This allows for both hyperspectral photoacoustic imaging and confocal imaging within the same system using only one light source 11. This "one source, two uses" design not only simplifies the system structure and reduces costs but also ensures the spatiotemporal synchronization and registration of the two imaging modes, providing a solid foundation for subsequent multimodal 3D information fusion.

[0059] In some embodiments, the scanning system 10 further includes a frame memory 22 and a scan generator 23. The frame memory 22 is communicatively connected to the photodetector 14 and the ultrasonic transducer 13, and is used to receive electrical signals generated by the photodetector 14 and the ultrasonic transducer 13. The scan generator 23 is communicatively connected to the planar beam scanner 17, the drive mechanism 21 of the objective lens group 19, and the frame memory 22, and is used to control the deflection of the planar beam scanner 17 and the movement of at least one lens in the objective lens group 19, so that the electrical signals generated by the photodetector 14 and the ultrasonic transducer 13 at the same coordinate position on each focal plane correspond, and the electrical signals generated by the photodetector 14 and the ultrasonic transducer 13 at different coordinate positions on the same focal plane correspond. It is understood that by corresponding the electrical signals generated by the photodetector 14 and the ultrasonic transducer 13 at the same coordinate position on the same focal plane through the scan generator 23, the information acquired by the photodetector 14 and the ultrasonic transducer 13 can be effectively combined, improving the accuracy of diagnosis and treatment. By aligning the electrical signals generated by the photodetector 14 and the ultrasonic transducer 13 at different coordinate positions on the same focal plane, two-dimensional image information on a specific focal plane can be constructed. Furthermore, when two-dimensional image information on multiple focal planes is obtained, it can be reconstructed into three-dimensional image information, enhancing the richness of scanning functions and improving the accuracy of diagnosis and treatment.

[0060] Specifically, the scan generator 23, serving as the timing and control center of the scanning system 10, is configured to generate a high-precision synchronization clock signal to coordinate the laser pulse emission of the light source 11, the deflection angle of the planar beam scanner 17, the axial position of the moving lens of the drive mechanism 21, and the sampling timing of the data acquisition card (ADC). Through this precise synchronization control, the scanning system 10 ensures that every scan spot (e.g., ...) irradiates the tissue. Figure 1As shown, the spatial coordinates of the light spot A generated at time t1 and the light spot A' generated at time t2 are mapped to each image pixel (e.g., signal points B and B') ultimately presented on the display screen 27 through a predetermined scanning path and display coordinate mapping relationship. This establishes a strict one-to-one correspondence. This deterministic mapping from "physical scan point" to "image pixel" enables distortion-free, high-fidelity image reconstruction. The frame memory 22 is not only responsible for caching the original confocal photon counting signal and photoacoustic voltage signal, but also undertakes the key task of recombining the time-series signal stream into spatial two-dimensional image frames and further stacking them into a three-dimensional data volume. The scanning system 10 can acquire a series of high-resolution two-dimensional tomographic images from the tissue surface to the deep layers in the form of optical slices. Finally, the computer superimposes and reconstructs these spatially precisely registered two-dimensional slice sequences to seamlessly generate confocal three-dimensional microscopic structure images and photoacoustic three-dimensional functional images, thereby realizing three-dimensional, multi-parameter analysis of the detected object 30 from the microscopic surface morphology to the deep functional vascular network.

[0061] The scanning system 10 provided in some embodiments of this application ensures precise registration of confocal optical images and photoacoustic images in spatial coordinates by sharing the same optical illumination, scanning, and focusing system. Simultaneously, a driving mechanism 21 is employed to realize a dynamic optical focusing mechanism, replacing the traditional mechanical advance and retreat of the probe. This achieves high-speed, non-invasive optical tomography, providing clinicians with integrated, high-precision diagnostic information ranging from microscopic cell morphology to macroscopic three-dimensional functional structures, greatly enhancing diagnostic capabilities and reliability in areas such as early tumor diagnosis and cardiovascular plaque vulnerability assessment.

[0062] In some embodiments, the scanning system 10 further includes a collimating lens group 24, which may include multiple lenses. Some lenses of the collimating lens group 24 may be disposed along the optical path between the light source 11 and the first light-blocking element 15, while other lenses may be disposed along the optical path between the first light-blocking element 15 and the light-combining element 12. The lenses disposed between the light source 11 and the first light-blocking element 15 can focus the light emitted by the light source 11 and allow it to pass through the first light-transmitting hole 151. The collimating lens group 24 as a whole can collimate the light emitted by the light source 11, so as to facilitate the propagation of light in the subsequent optical path and improve the scanning quality.

[0063] The scanning system 10 also includes a field lens 25, which comprises one or more lenses with optical power. The field lens 25 is positioned along the optical path between the planar beam scanner 17 and the coherent fiber bundle 18, and is used to converge and couple the light emitted from the planar beam scanner 17 into the fiber. The scanning system 10 also includes a focusing lens group 26, which comprises one or more lenses with optical power. The focusing lens group 26 is positioned along the optical path between the light combining element 12 and the second light blocking element 16, and is used to focus the light from the light combining element 12 so that the light can pass through the second light transmission aperture 161, thereby improving the light utilization efficiency and signal-to-noise ratio. Of course, the number and arrangement of lenses in the collimating lens group 24, the field lens 25, and the focusing lens group 26 are not limited, and can be designed according to the dimming requirements, and are not limited in this application.

[0064] This application also provides an endoscope, including a scanning system 10 as described in any of the above embodiments. The endoscope may further include a main unit, a mirror body, and a transmission component. At least a portion of the mirror body is used to extend into the patient's body. The main unit is used for communication and operation outside the patient's body, and the transmission component is used to provide signal transmission between the main unit and the mirror body. When the scanning system 10 is mounted on the endoscope, components such as the light source 11, collimating lens group 24, first light blocking element 15, photodetector 14, second light blocking element 16, focusing lens group 26, light combining element 12, plane beam scanner 17, and field lens 25, divided by the coherent fiber bundle 18, can be disposed on the handle of the main unit or integrated inside the main unit. The objective lens group 19, ultrasonic transducer 13, and drive mechanism 21 can be disposed on the mirror body. Specifically, the objective lens group 19, ultrasonic transducer 13, and drive mechanism 21 can be disposed at the end of the mirror body (i.e., the end portion of the endoscope) so that they extend into the patient's body along with the end portion, facilitating the acquisition of signals from the patient's tissues. At least a portion of the coherent fiber bundle 18 can be disposed on the transmission component and perform optical signal transmission function on the transmission component. The frame memory 22 and the scan generator 23 can both be disposed in the host. The transmission component can also be provided with structures such as wires that communicate with the ultrasonic transducer 13 and the frame memory 22, so as to perform electrical signal transmission function in the transmission component.

[0065] The scanning system 10 provided in this application can be used as a standalone endoscope system, such as a flexible endoscope specifically for gastrointestinal imaging, or integrated into a miniaturized catheter form. It can be inserted into the patient's body through the instrument channels of conventional digestive endoscopes or rigid endoscopes, working in conjunction with traditional endoscopic techniques to upgrade diagnostic capabilities. In the cardiovascular field, when the scanning system 10 operates within blood vessels, its confocal optical imaging capability can provide high-resolution optical imaging of the microstructure of vascular endothelial cells and the fibrous cap of atherosclerotic plaques. Its photoacoustic three-dimensional scanning can penetrate the surface to identify the easily ruptured lipid core within the plaque. Furthermore, through multispectral analysis of hemoglobin and lipids, it can quantitatively assess plaque vulnerability, providing in-situ diagnostic information for the prevention of acute myocardial infarction and stroke.

[0066] In the field of gastroenterology, the scanning system 10 can be integrated into a gastroscope or colonoscope, or used as a catheter to reach the esophagus, stomach, and colon via the biopsy channel of a conventional endoscope. At locations of suspicious mucosal changes or early lesions, the scanning system 10 can perform optical biopsies using confocal optical imaging, determining the benign or malignant nature of tissue at the cellular level. Its photoacoustic 3D scanning can non-invasively assess the depth of lesion infiltration in the submucosa and the abnormal proliferation of surrounding vascular networks, enabling the determination of tumor staging and nature, and optimizing the selection and planning of endoscopic treatment. In clinical scenarios requiring rigid endoscopes, such as thoracoscopy, laparoscopy, hysteroscopy, and cystoscopy, the scanning system 10 can also be integrated or used as a probe. In oncological surgery, the scanning system 10 can rapidly scan suspicious tissues in the surgical field. Confocal optical imaging can be used to confirm whether cancer cells remain at the surgical margin, while photoacoustic 3D imaging can delineate the three-dimensional boundaries of deep tumors and their proximity to key blood vessels, achieving precise surgical navigation from macro to micro, ensuring thorough tumor resection and surgical safety.

[0067] The scanning system 10 has demonstrated immense potential in numerous fields, including respiratory medicine (via bronchoscopy), otolaryngology, and neurosurgery. It overcomes the limitations of traditional endoscopes, which can only observe surface morphology, by simultaneously acquiring fused information on "cellular structure, deep functional components, and three-dimensional spatial morphology" in a single examination. Whether used as a standalone device or a collaborative module, it will become a powerful "intelligent scalpel" in the hands of clinicians, laying a solid technological foundation for early and accurate disease diagnosis, individualized minimally invasive treatment planning, and real-time navigation and evaluation of the surgical process.

[0068] Based on the scanning system 10 described in any of the above embodiments, this application also provides a three-dimensional image construction method, which can use the scanning system 10 described in any of the above embodiments to scan the object 30 to obtain two-dimensional image information or three-dimensional image information of the object 30. In some embodiments, the three-dimensional image construction method includes:

[0069] The scanning generator 23 controls the planar beam scanner 17 to transmit the light emitted by the light source 11 sequentially through different light rays of the coherent fiber bundle 18 onto the object being inspected 30.

[0070] The photodetector 14 sequentially collects light rays emitted from the object being tested 30 through different optical fibers;

[0071] The ultrasonic transducer 13 sequentially collects ultrasonic signals emitted by the object under test 30 at different optical fiber positions.

[0072] The electrical signals generated by the photodetector 14 and the ultrasonic transducer 13 are correlated with the coordinate positions of different optical fibers.

[0073] It can be seen that by combining the planar beam scanner 17 and the coherent fiber bundle 18, optical signals and photoacoustic signals at different coordinate positions on a certain focal plane can be acquired, which is beneficial for constructing two-dimensional image information on a certain focal plane and realizing the effective combination of optical signals and photoacoustic signals at the coordinate level.

[0074] Furthermore, in some embodiments, the three-dimensional image construction method further includes:

[0075] The scanning generator 23 controls the drive mechanism 21 of the objective lens group 19 to move at least one lens to correspond sequentially with different focal plane positions.

[0076] The scanning generator 23 controls the planar beam scanner 17 to transmit the light emitted by the light source 11 sequentially through different optical fibers of the coherent fiber bundle 18 to the object being tested 30 at each position corresponding to the focal plane.

[0077] Optical and ultrasonic signals corresponding to the coordinate positions of different optical fibers on each focal plane are sequentially acquired using photodetector 14 and ultrasonic transducer 13.

[0078] It is understandable that each time the lens in the objective lens group 19 moves, the information of each coordinate position on one of the focal planes can be collected through the cooperation of the plane beam scanner 17 and the coherent fiber bundle 18, thereby realizing the construction of two-dimensional image information of one of the focal planes. When the lens in the objective lens group 19 moves multiple times, two-dimensional image information of multiple focal planes can be obtained, thereby reconstructing the three-dimensional image information of the object under test 30.

[0079] Specifically, when acquiring the three-dimensional image information of the object under test 30, the optical and photoacoustic information at a certain coordinate position on one of the focal planes can be acquired first, and then the optical and photoacoustic information at another coordinate position on the same focal plane can be acquired. After acquiring the optical and photoacoustic information at all coordinate positions on the same focal plane, the two-dimensional image information of the object under test 30 corresponding to the focal plane can be reconstructed. Then, the two-dimensional image information of other focal planes can be acquired in the same way, and the three-dimensional image information of the object under test 30 can be reconstructed.

[0080] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A scanning system, characterized in that, Includes light source, light combining element, ultrasonic transducer and photodetector; The light combining element is configured to conduct at least a portion of the light emitted by the light source to the ultrasonic transducer, and the ultrasonic transducer is configured to transmit at least a portion of the light transmitted from the light combining element to the ultrasonic transducer to the object being tested, and to transmit at least a portion of the light returning from the object being tested to the ultrasonic transducer to the light combining element. The light combining element is also configured to conduct at least a portion of the light transmitted from the ultrasonic transducer to the light combining element to the photodetector.

2. The scanning system according to claim 1, characterized in that, The light combining element includes a dichroic mirror. The light emission direction of the light source intersects with the light combining element. The photodetector is disposed on the side of the light combining element facing away from the ultrasonic transducer along the optical path. The light combining element can reflect at least a portion of the light emitted by the light source and transmit at least a portion of the light transmitted to the light combining element through the ultrasonic transducer.

3. The scanning system according to claim 1, characterized in that, The scanning system further includes an objective lens assembly disposed between the light combining element and the ultrasonic transducer along the optical path, wherein at least one lens in the objective lens assembly is configured to be movable relative to the ultrasonic transducer in a direction parallel to the optical axis.

4. The scanning system according to claim 1, characterized in that, The scanning system further includes a first light-blocking component and a second light-blocking component. The first light-blocking component is disposed along the optical path between the light source and the light-combining element and has a first light-transmitting hole. The second light-blocking component is disposed along the optical path between the light-combining element and the photodetector and has a second light-transmitting hole. The positions of the first light-blocking component and the second light-blocking component on the optical path are conjugate with respect to the object being detected.

5. The scanning system according to claim 1, characterized in that, The light source includes a tunable laser source, the wavelength of which is tuned in the range of 450nm-950nm; and / or, The scanning system includes a first observation mode and a second observation mode. In the first observation mode, the wavelength range emitted by the light source is 450nm-800nm, and in the second observation mode, the wavelength range emitted by the light source is 680nm-950nm.

6. The scanning system according to claim 1, characterized in that, The scanning system further includes a planar beam scanner and a coherent fiber bundle, the coherent fiber bundle being disposed along the optical path between the planar beam scanner and the ultrasonic transducer, the coherent fiber bundle comprising multiple optical fibers arranged side by side, and the planar beam scanner being configured to selectively direct at least a portion of the light transmitted from the light combining element to the planar beam scanner onto any one of the optical fibers in the coherent fiber bundle.

7. The scanning system according to claim 6, characterized in that, The scanning system further includes a frame memory, a scan generator, and an objective lens assembly. The frame memory is communicatively connected to the photodetector and the ultrasonic transducer, and is used to receive electrical signals generated by the photodetector and the ultrasonic transducer. The objective lens assembly is disposed between the beam combining element and the ultrasonic transducer. At least one lens in the objective lens assembly is configured to move relative to the ultrasonic transducer along a direction parallel to the optical axis. The scan generator is communicatively connected to the planar beam scanner, the drive mechanism of the objective lens assembly, and the frame memory, and is used to control the deflection of the planar beam scanner and the movement of at least one lens in the objective lens assembly, so that the electrical signals generated by the photodetector and the ultrasonic transducer at the same coordinate position on each focal plane correspond, and the electrical signals generated by the photodetector and the ultrasonic transducer at different coordinate positions on the same focal plane correspond.

8. An endoscope, characterized in that, The system includes a host, a transmission component, a mirror body, and a scanning system as described in any one of claims 1-7, wherein the transmission component is used to provide signal transmission between the host and the mirror body, the light source, the light combining element, and the photodetector are disposed within the host, and the ultrasonic transducer is disposed within the mirror body.

9. A method for constructing a three-dimensional image, characterized in that, include: The planar beam scanner, controlled by the scanning generator, transmits the light emitted by the light source sequentially through different fibers of the coherent fiber bundle onto the object being inspected. The photodetector sequentially collects light rays emitted from the object being detected through different optical fibers; The ultrasonic transducer sequentially collects ultrasonic signals emitted by the object under test corresponding to different positions of the optical fiber; The electrical signals generated by the photodetector and the ultrasonic transducer are correlated with the coordinate positions of different optical fibers.

10. The three-dimensional image construction method according to claim 9, characterized in that, The three-dimensional image construction method also includes: The scanning generator controls the drive mechanism of the objective lens group to move at least one lens to correspond sequentially to different focal plane positions. The planar beam scanner is controlled by a scanning generator to transmit the light emitted by the light source sequentially through different fibers of the coherent fiber bundle to the object being detected at each position corresponding to the focal plane. The photodetector and the ultrasonic transducer sequentially collect light rays and ultrasonic signals corresponding to the coordinate positions of different optical fibers on each focal plane.

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