A multispectral imaging method for an electronic human angioscope

Abstract

The present application relates to a kind of multispectral imaging methods for human electronic angioscope, belong to medical instrument technical field.Therein, the method includes: by ultramicro infrared enhanced image sensor, photoelectric signal conversion is carried out to target near-infrared spectrum, based on focusing lens, the imaging light in blood vessel is focused, the overall specification is calibrated to adapt to the intervention demand of most blood vessels of human body;Based on the requirement of avoiding blood interference, preset three kinds of near-infrared spectrum wave band, corresponding multispectral light source is built and is coupled with endoscope optics;Under the assistance of image device, endoscope is pushed to target blood vessel, and image is collected according to wave band and is transmitted to external terminal;Terminal passes through adaptive algorithm, and noise reduction, signal enhancement, generates visual image.It realizes real-time optical direct imaging in blood vessel, solves the problems such as no direct optical imaging, blood interference, low resolution of traditional technology, improves the lesion recognition clarity and diagnostic efficiency, provides support for intravascular precise diagnosis and treatment.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a multispectral imaging method for human electronic angiography. Background Technology

[0002] In the diagnosis of vascular lesions (such as calcification, tumors, and stent-related abnormalities), accurate imaging is crucial for treatment decisions. Current mainstream vascular imaging technologies have significant limitations: ultrasound, CTA, and MRA are mostly external imaging techniques or rely on algorithmic reconstruction, failing to provide direct, intuitive optical images; DSA, while offering high resolution, is an invasive procedure with high radiation doses and risks of complications; OCT / IVUS, while enabling intravascular imaging, requires stringent operational skills and involves expensive equipment; traditional fiber optic endoscopes, although capable of entering blood vessels, rely on external imaging devices, resulting in low pixel counts (typically only a few thousand to twenty thousand) and the lack of a focusing lens, leading to blurry images and difficulty in clearly presenting lesion details. These technologies cannot meet the demand for real-time, high-resolution direct optical imaging of the vascular cavity, leading to uncertainty in lesion identification by physicians and affecting diagnostic efficiency and accuracy. Therefore, there is an urgent need for novel direct optical imaging solutions adapted to vascular interventional scenarios. Summary of the Invention

[0003] To address the aforementioned problems in the existing technology, this invention provides a multispectral imaging method for human electronic angiography.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] S1: The near-infrared spectrum of the target is converted into photoelectric signals by an ultra-miniature infrared-enhanced image sensor, and the imaging light inside the blood vessel is focused by a focusing lens; the overall specifications are calibrated to adapt to the interventional needs of most blood vessels in the human body, and the calibrated size data and photoelectric performance parameters are obtained.

[0006] S2: Based on the need to avoid blood interference during intravascular imaging, three target spectral bands are preset; a multispectral light source corresponding to the target spectral bands is constructed, and each band is individually turned on, switched sequentially, or started in combination by configuring an independent controller; the light source is optically coupled to the endoscope body;

[0007] S3: With the aid of imaging equipment for positioning, the prepared endoscope is slowly pushed into the target blood vessel through the catheter path, and the pushing speed and direction are controlled until the tip reaches the vicinity of the lesion site; the light source and sensor are activated, and the light source is turned on in sequence according to the set spectral bands. The sensor synchronously collects the internal images of the blood vessel under the corresponding spectrum, and improves the photoelectric conversion effect by using its own infrared enhancement characteristics. After converting the light signal into an electrical signal, it is transmitted to the external data processing terminal in real time.

[0008] S4: After receiving the image electrical signal, the external data processing terminal uses an adaptation algorithm to reduce noise and enhance contrast based on the image characteristics of different spectral bands, eliminates noise generated by blood scattering, and strengthens the difference between the lesion area and normal tissue; and converts the processed signal into a visual image format.

[0009] Specifically, the photoelectric signal conversion of the target near-infrared spectrum is performed as follows: the target near-infrared light signal is filtered by the ultra-miniature infrared enhancement sensor to remove stray light in the non-target band; the remaining light signal enters the photosensitive array and is absorbed by the photosensitive unit and converted into charge carriers; the charge carriers form a weak current under the action of an electric field, which is amplified by the internal circuit through multiple stages and converted into a stable electronic signal; at the same time, the electronic signal intensity output is matched with the receiving threshold of the external data processing terminal by adjusting the circuit gain.

[0010] Specifically, the process of adjusting the circuit gain mechanism to match the output electronic signal strength with the receiving threshold of the external data processing terminal is as follows: First, the signal receiving threshold range of the external data processing terminal is pre-obtained; then, in the electronic signal output stage, the current amplified electronic signal strength data is collected in real time; the collected signal strength is compared with the preset threshold range; if the signal strength is lower than the preset threshold, the amplification factor is increased through the circuit gain adjustment mechanism; if it is higher than the preset threshold, the amplification factor is decreased; this adjustment and comparison process is repeated until the electronic signal strength stably falls within the threshold range; and finally, the final gain parameter is recorded.

[0011] Specifically, the dedicated focusing lens is used to accurately focus the near-infrared light reflected from the lesion site within the blood vessel onto the photosensitive area of ​​the sensor. The lens consists of multiple lenses with different curvatures. After the reflected light enters the lens, it is refracted sequentially through the lenses. The curvature parameters of the lenses are preset according to the distance between the lesion site and the lens. By adjusting the relative positions between the lenses, the focal point formed by the refracted light falls on the center of the photosensitive area of ​​the sensor, thus focusing all the reflected light from the lesion site into the photosensitive area.

[0012] Specifically, the overall calibration specifications are used to adjust the relative positions of the ultra-miniature infrared enhanced sensor and the dedicated focusing lens. The specific process is as follows: by comparing the axial deviation value of the dedicated focusing lens through laser beam projection, the lens angle and depth are gradually fine-tuned; a microscope is used to mark reference points, and the alignment deviation between the center of the photosensitive area of ​​the ultra-miniature infrared enhanced sensor and the focal point of the lens is observed, and the axes of the two are precisely aligned by displacement adjustment; at the same time, a precision measurement tool is used to obtain the overall specification data, and if it exceeds the preset range suitable for most blood vessels in the human body, the size is adjusted to the standard range through controllable precision correction.

[0013] Specifically, the three target spectral bands preset based on the need to avoid blood interference during intravascular imaging are used to collect image information at different depths of the blood vessel: the light of the first band is mostly reflected by the superficial structure after it shines on the blood vessel wall, and a small amount is absorbed by the deep tissue, reducing the absorption of light signals by hemoglobin and allowing more light signals reflected by the superficial structure of the blood vessel wall to reach the sensor; the light of the second band can penetrate to the middle layer of the blood vessel wall, is reflected by the middle layer structure and returns, and is used to supplement the collection of light signals reflected by the middle layer structure of the blood vessel wall; the light of the third band can penetrate the flowing blood, is reflected by the deep lesions of the blood vessel or the surface of the stent and returns through the blood, and is used to weaken the absorption and scattering of light signals by the blood, allowing the light signals reflected by the deep lesions of the blood vessel or the surface of the stent to penetrate the blood and reach the sensor.

[0014] Specifically, after the multispectral light source is built, wavelength accuracy calibration is required; the spectrometer's detection probe is aligned with the light source output port, and the light sources of each band are turned on; the spectrometer acquires the spectral distribution curve of the light source in real time and records the wavelength value corresponding to the peak value of the curve; the measured peak wavelength is compared with the center wavelength of the preset target band, and if the deviation exceeds the allowable range, it is corrected by adjusting the filter angle or driving current inside the light source; the calibration operation is repeated for each band until the measured peak wavelength of each band falls within the preset target band range.

[0015] As a preferred embodiment of the present invention, the independent controller configured for each band is used to adjust the light source according to the detection requirements of different vascular lesions: the controller has a built-in storage mechanism for the correspondence between lesion type and band. When vascular calcification is detected, it receives an externally input calcification detection command, calls the corresponding control program in the storage mechanism, triggers the driving circuit of the third type of band light source, and turns on the third type of band light source alone. It uses the penetrability of this band to collect the density difference signal between the calcified area and the surrounding tissue. When vascular tumor is detected, it receives a tumor detection command, calls the corresponding program, alternately triggers the driving circuits of the first and second type of band light sources, switches on the first and second type of band light sources, and collects the reflected light difference signal between the tumor edge and the normal blood vessel wall.

[0016] Specifically, the optical coupling of the light source and the endoscope body for alignment via fiber optic interface and lens refraction calibration involves the following steps: cleaning the interface between the light source output and the endoscope's light transmission channel input; aligning the center of the fiber optic interface with the center of the light transmission channel and locking the interface with a locking clip; adjusting the lens angle at the light source output so that the light signal output by the light source is refracted by the lens and enters the light transmission channel inside the endoscope; and fine-tuning the lens angle by detecting the shape of the light spot at the endoscope's front light outlet until the light spot coverage area coincides with the sensor's imaging field of view.

[0017] Specifically, the control of the pushing speed and direction is used in conjunction with the real-time display of the vascular path by the imaging equipment: the imaging equipment generates dynamic images of the inside of the blood vessel in real time, and the operator identifies the straight and curved segments of the blood vessel by observing the images; in the straight segment of the blood vessel, the endoscope is kept moving forward at a constant speed by the uniform speed drive mechanism of the pushing device; in the curved segment of the blood vessel, the operator uses the control lever to fine-tune the angle of the pushing device to slow down the pushing speed and change the curvature angle of the endoscope tip, so that the tip moves along the direction of the blood vessel curvature, avoiding the tip from colliding with the endothelial cells at the bend of the blood vessel and causing cell detachment; at the same time, the distance between the endoscope and the blood vessel wall is observed by the image, and the pushing direction is adjusted to advance the endoscope along the central axis of the blood vessel until the image shows that the tip has reached the vicinity of the lesion site.

[0018] Specifically, the infrared antireflection film on the sensor surface, which enhances photoelectric conversion efficiency by leveraging its own infrared enhancement characteristics, allows near-infrared light signals to pass through, reducing the reflection loss of light signals on the film surface. After the light signal enters the sensor, the photosensitive material in the sensitive photosensitive element absorbs the weak near-infrared light signal and generates charge carriers corresponding to the light intensity. The internal signal amplification circuit amplifies the weak current formed by the charge carriers in multiple stages, converting the light signal, which was originally below the detection threshold, into an electronic signal that can be recognized by an external terminal.

[0019] Specifically, when the sensor converts the optical signal into an electrical signal and transmits it to an external data processing terminal in real time, anti-interference processing of the transmission link is required. Shielded twisted-pair cable is used as the signal transmission cable, with the outer layer of the cable wrapped with a metal shield and grounded to block external electromagnetic signals from interfering with the transmission line. Signal filtering is performed at the signal output end of the sensor and the signal input end of the terminal to filter out high-frequency noise mixed in during transmission. Before transmission, the electrical signal is encoded to convert the original signal into an anti-interference encoding format. After receiving the signal, the terminal decodes it to restore the original signal.

[0020] Specifically, the method of using an adaptation algorithm to eliminate clutter generated by blood scattering is used to perform multi-frame superposition processing on the received image electrical signals. The specific process is as follows: frame synchronization is performed on the continuously acquired multi-frame image signals to determine the corresponding position of the same lesion area in the multi-frame; the signal intensity of the same position in different frames is compared, and stable signals with intensity fluctuations within a preset range are selected, while instantaneous strong scattering clutter caused by blood flow is eliminated; at the same time, by analyzing the grayscale characteristics of the lesion area and clutter, a preset grayscale threshold is set, and grayscale signals below the threshold are identified as clutter and filtered out, while only the effective grayscale signals of the lesion area exceeding the threshold are retained.

[0021] Specifically, when the external data processing terminal enhances the difference between the lesion area and normal tissue, it needs to adjust the algorithm parameters in combination with the tissue optical properties. The specific process is as follows: preset the optical reflection characteristics data of different vascular tissues (such as normal blood vessel walls, tumors, and calcifications); when processing images, the algorithm extracts the reflected light intensity features of each region in the current image, compares them with the preset data, and identifies suspected lesion areas; for the identified areas, automatically increase the grayscale difference between them and the surrounding normal tissues—if it is a suspected tumor area, enhance its texture contrast with the normal blood vessel wall; if it is a suspected calcification area, enhance its density contrast with the surrounding tissues, making the lesion features easier to identify clinically.

[0022] Specifically, the process of converting the processed signal into a visual image format for pixel arrangement according to the sensor's photosensitive area involves: determining the pixel coordinates corresponding to each electronic signal; mapping the intensity value of the electronic signal to the corresponding grayscale value; arranging the grayscale values ​​of the pixels in coordinate order to generate a bitmap format image, where the grayscale value of each pixel in the image corresponds to the intensity of reflected light from the lesion site; and simultaneously creating a multispectral image switching interface, which includes switching controls corresponding to three bands. When the doctor operates the controls, the system calls the image data of the corresponding band and refreshes the display area.

[0023] Specifically, after the endoscope completes one intravascular imaging, it is placed back into the test device simulating the vascular environment, and the imaging performance test steps are repeated to acquire images of the simulated lesion area. The acquired images are compared with the test images before use to check whether the image clarity and signal strength are consistent. If there is a significant difference, the endoscope is disassembled to check whether the components are loose or damaged, and then reassembled, calibrated, and tested again. After confirming that the performance is stable, the number of uses and the retest results are recorded as the basis for endoscope maintenance or replacement.

[0024] The beneficial effects of this invention are as follows:

[0025] (1) By setting up an ultra-miniature infrared-enhanced endoscope image sensor and a dedicated focusing lens, it can penetrate into most blood vessels in the human body to perform direct near-infrared spectral imaging without relying on algorithm reconstruction or external imaging equipment. It can avoid the imaging blurring problem caused by the low pixel count and lack of focus of traditional fiber endoscopes, and can clearly present the detailed features of lesions such as tumors, calcifications, and stents in blood vessels, helping doctors to intuitively obtain lesion information and improve the accuracy and efficiency of diagnosis.

[0026] (2) By setting up three types of target spectral bands and corresponding independent controllers based on the need to avoid blood interference in intravascular imaging, the influence of blood absorption and scattering on imaging can be reduced in a targeted manner. At the same time, it can flexibly realize single-band activation, multi-band switching or combined activation, and can collect image information of superficial, middle and deep vascular structures respectively, adapt to the detection needs of lesions at different depths, solve the problem of difficulty in lesion identification caused by blood interference in traditional imaging technology, and broaden the applicable scenarios of intravascular diagnosis. Attached Figure Description

[0027] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0028] Figure 1 This is an architectural diagram of a multispectral imaging method for human electronic angiography according to the present invention.

[0029] Figure 2 This is a control flow diagram of a multispectral imaging method for human electronic angiography according to the present invention. Detailed Implementation

[0030] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0031] Please see Figure 1-2 A multispectral imaging method for human electronic angiography

[0032] S1: The near-infrared spectrum of the target is converted into photoelectric signals by an ultra-miniature infrared-enhanced image sensor, and the imaging light inside the blood vessel is focused by a focusing lens; the overall specifications are calibrated to adapt to the interventional needs of most blood vessels in the human body, and the calibrated size data and photoelectric performance parameters are obtained.

[0033] S2: Based on the need to avoid blood interference during intravascular imaging, three target spectral bands are preset; a multispectral light source corresponding to the target spectral bands is constructed, and each band is individually turned on, switched sequentially, or started in combination by configuring an independent controller; the light source is optically coupled to the endoscope body;

[0034] S3: With the aid of imaging equipment for positioning, the prepared endoscope is slowly pushed into the target blood vessel through the catheter path, and the pushing speed and direction are controlled until the tip reaches the vicinity of the lesion site; the light source and sensor are activated, and the light source is turned on in sequence according to the set spectral bands. The sensor synchronously collects the internal images of the blood vessel under the corresponding spectrum, and improves the photoelectric conversion effect by using its own infrared enhancement characteristics. After converting the light signal into an electrical signal, it is transmitted to the external data processing terminal in real time.

[0035] S4: After receiving the image electrical signal, the external data processing terminal uses an adaptation algorithm to reduce noise and enhance contrast based on the image characteristics of different spectral bands, eliminates noise generated by blood scattering, and strengthens the difference between the lesion area and normal tissue; and converts the processed signal into a visual image format.

[0036] Specifically, the photoelectric signal conversion of the target near-infrared spectrum is performed as follows: the target near-infrared light signal is filtered by the ultra-miniature infrared enhancement sensor to remove stray light in the non-target band; the remaining light signal enters the photosensitive array and is absorbed by the photosensitive unit and converted into charge carriers; the charge carriers form a weak current under the action of an electric field, which is amplified by the internal circuit through multiple stages and converted into a stable electronic signal; at the same time, the electronic signal intensity output is matched with the receiving threshold of the external data processing terminal by adjusting the circuit gain.

[0037] Specifically, the process of adjusting the circuit gain mechanism to match the output electronic signal strength with the receiving threshold of the external data processing terminal is as follows: First, the signal receiving threshold range of the external data processing terminal is pre-obtained; then, in the electronic signal output stage, the current amplified electronic signal strength data is collected in real time; the collected signal strength is compared with the preset threshold range; if the signal strength is lower than the preset threshold, the amplification factor is increased through the circuit gain adjustment mechanism; if it is higher than the preset threshold, the amplification factor is decreased; this adjustment and comparison process is repeated until the electronic signal strength stably falls within the threshold range; and finally, the final gain parameter is recorded.

[0038] In this embodiment, the endoscope has an outer diameter of 0.83 mm. This size ensures that the endoscope can smoothly enter most blood vessels in the human body, except for tiny capillaries at the tip, so as to achieve close observation of the lesion site. Because it uses an ultra-miniature sensor with a small outer diameter (currently 0.83 mm), it can enter most blood vessels in the human body, except for relatively tiny capillaries at the tip, so as to closely observe the lesion site.

[0039] Specifically, the ultra-miniature infrared-enhanced endoscope image sensor is used to receive light signals from three preset target near-infrared spectral bands. The light signals first pass through a filter layer on the sensor surface to filter out stray light from non-target bands; then they enter the photosensitive array, where photosensitive units absorb photons from the light signals and convert them into charge carriers; the charge carriers form a current under the action of an electric field, which is amplified by the internal circuit and converted into corresponding electronic signals; and under these three near-infrared bands, the output electronic signal intensity is matched to the signal reception threshold of the external data processing terminal by adjusting the circuit gain.

[0040] In this embodiment, the endoscope uses a resolution of 40,000 pixels or higher, while referencing the 6,000-20,000 pixel range of traditional fiber endoscopes. The combination of high resolution and a dedicated focusing lens solves the problem of blurry imaging in traditional fiber endoscopes. The part of the fiber endoscope that enters the human body is the head end of the fiber optic light guide column, which guides the fiber to the device outside the body for imaging. The problem with this is low resolution (usually 6,000-20,000) and blurry imaging (because a lens cannot be used). The endoscope of this invention can reach a resolution of 40,000 pixels or higher, and uses a lens for focusing, thus achieving higher clarity.

[0041] In this embodiment, an ultra-miniature infrared-enhanced endoscopic image sensor is used. This sensor is designed for the 650-700nm, 800-900nm, and 1300nm / 1550nm / 1800nm ​​spectral regions. The infrared enhancement characteristics of the sensor can significantly improve the photoelectric conversion efficiency of the target spectral region. Even in the weak light and multi-interference environment inside blood vessels, it can convert weak light signals into stable and recognizable electrical signals, avoiding excessive image noise and loss of lesion information due to weak signals, and ensuring the clarity and reliability of real-time imaging.

[0042] Specifically, the dedicated focusing lens is used to accurately focus the near-infrared light reflected from the lesion site within the blood vessel onto the photosensitive area of ​​the sensor. The lens consists of multiple lenses with different curvatures. After the reflected light enters the lens, it is refracted sequentially through the lenses. The curvature parameters of the lenses are preset according to the distance between the lesion site and the lens. By adjusting the relative positions between the lenses, the focal point formed by the refracted light falls on the center of the photosensitive area of ​​the sensor, thus focusing all the reflected light from the lesion site into the photosensitive area.

[0043] In this embodiment, the dedicated focusing lens is not designed independently, but rather adapted in conjunction with the pixel specifications of the ultra-miniature infrared-enhanced endoscope image sensor. Traditional fiber endoscopes suffer from blurred images due to the inability to use lenses, and their pixel count is typically only 6,000-20,000. In this embodiment, the dedicated focusing lens, through a combination of multiple lenses with different curvatures, precisely focuses the near-infrared light reflected from lesions within the blood vessels onto the sensor's photosensitive area. Simultaneously, it is paired with an ultra-miniature infrared-enhanced sensor with a pixel count of over 40,000. Together, they solve the core defects of traditional fiber endoscopes, namely, the lack of lenses and low pixel count. Specifically, the focusing lens ensures that the reflected light covers the photosensitive area without diffusion, while the high pixel count of over 40,000 captures the subtle textures of the lesion (such as the irregular shape of tumor edges and the granularity of calcified areas), avoiding the loss of detail due to insufficient pixels. Ultimately, this achieves a clearer intravascular imaging effect than traditional fiber endoscopes.

[0044] Specifically, the overall calibration specifications are used to adjust the relative positions of the ultra-miniature infrared enhanced sensor and the dedicated focusing lens. The specific process is as follows: by comparing the axial deviation value of the dedicated focusing lens through laser beam projection, the lens angle and depth are gradually fine-tuned; a microscope is used to mark reference points, and the alignment deviation between the center of the photosensitive area of ​​the ultra-miniature infrared enhanced sensor and the focal point of the lens is observed, and the axes of the two are precisely aligned by displacement adjustment; at the same time, a precision measurement tool is used to obtain the overall specification data, and if it exceeds the preset range suitable for most blood vessels in the human body, the size is adjusted to the standard range through controllable precision correction.

[0045] Specifically, the three target spectral bands preset based on the need to avoid blood interference during intravascular imaging are used to collect image information at different depths of the blood vessel: the light of the first band is mostly reflected by the superficial structure after it shines on the blood vessel wall, and a small amount is absorbed by the deep tissue, reducing the absorption of light signals by hemoglobin and allowing more light signals reflected by the superficial structure of the blood vessel wall to reach the sensor; the light of the second band can penetrate to the middle layer of the blood vessel wall, is reflected by the middle layer structure and returns, and is used to supplement the collection of light signals reflected by the middle layer structure of the blood vessel wall; the light of the third band can penetrate the flowing blood, is reflected by the deep lesions of the blood vessel or the surface of the stent and returns through the blood, and is used to weaken the absorption and scattering of light signals by the blood, allowing the light signals reflected by the deep lesions of the blood vessel or the surface of the stent to penetrate the blood and reach the sensor.

[0046] In this embodiment, the three preset target spectral bands are respectively within the ranges of 650-700nm, 800-900nm, and 1300nm / 1550nm / 1800nm. The 650-700nm and 800-900nm bands can avoid the strong absorption peak of hemoglobin, reduce the absorption loss of light signals by blood, and ensure clear imaging of superficial and middle layers of the blood vessel wall (such as endothelial damage and smooth muscle layer lesions). The 1300nm / 1550nm / 1800nm ​​bands can weaken blood absorption and scattering, allowing light signals to penetrate deep blood and capture deep vascular lesions (such as calcification in the blood vessel wall) or stent surface information, solving the problem that traditional imaging technology cannot fully image lesions at different depths due to blood interference.

[0047] Specifically, after the multispectral light source is built, wavelength accuracy calibration is required; the spectrometer's detection probe is aligned with the light source output port, and the light sources of each band are turned on; the spectrometer acquires the spectral distribution curve of the light source in real time and records the wavelength value corresponding to the peak value of the curve; the measured peak wavelength is compared with the center wavelength of the preset target band, and if the deviation exceeds the allowable range, it is corrected by adjusting the filter angle or driving current inside the light source; the calibration operation is repeated for each band until the measured peak wavelength of each band falls within the preset target band range.

[0048] As a preferred embodiment of the present invention, the independent controller configured for each band is used to adjust the light source according to the detection requirements of different vascular lesions: the controller has a built-in storage mechanism for the correspondence between lesion type and band. When detecting vascular calcification lesions, it receives an externally input calcification detection command, calls the corresponding control program in the storage mechanism, triggers the driving circuit of the third type of band light source, and turns on the third type of band light source alone. It uses the penetrability of this band to collect the density difference signal between the calcified area and the surrounding tissue. When detecting vascular tumors, it receives a tumor detection command, calls the corresponding program, alternately triggers the driving circuits of the first and second type of band light sources, switches on the first and second type of band light sources, and collects the reflected light difference signal between the tumor edge and the normal blood vessel wall.

[0049] Specifically, the optical coupling of the light source and the endoscope body for alignment via fiber optic interface and lens refraction calibration involves the following steps: cleaning the interface between the light source output and the endoscope's light transmission channel input; aligning the center of the fiber optic interface with the center of the light transmission channel and locking the interface with a locking clip; adjusting the lens angle at the light source output so that the light signal output by the light source is refracted by the lens and enters the light transmission channel inside the endoscope; and fine-tuning the lens angle by detecting the shape of the light spot at the endoscope's front light outlet until the light spot coverage area coincides with the sensor's imaging field of view.

[0050] Specifically, the control of the pushing speed and direction is used in conjunction with the real-time display of the vascular path by the imaging equipment: the imaging equipment generates dynamic images of the inside of the blood vessel in real time, and the operator identifies the straight and curved segments of the blood vessel by observing the images; in the straight segment of the blood vessel, the endoscope is kept moving forward at a constant speed by the uniform speed drive mechanism of the pushing device; in the curved segment of the blood vessel, the operator uses the control lever to fine-tune the angle of the pushing device to slow down the pushing speed and change the curvature angle of the endoscope tip, so that the tip moves along the direction of the blood vessel curvature, avoiding the tip from colliding with the endothelial cells at the bend of the blood vessel and causing cell detachment; at the same time, the distance between the endoscope and the blood vessel wall is observed by the image, and the pushing direction is adjusted to advance the endoscope along the central axis of the blood vessel until the image shows that the tip has reached the vicinity of the lesion site.

[0051] Specifically, the infrared antireflection film on the sensor surface, which enhances photoelectric conversion efficiency by leveraging its own infrared enhancement characteristics, allows near-infrared light signals to pass through, reducing the reflection loss of light signals on the film surface. After the light signal enters the sensor, the photosensitive material in the sensitive photosensitive element absorbs the weak near-infrared light signal and generates charge carriers corresponding to the light intensity. The internal signal amplification circuit amplifies the weak current formed by the charge carriers in multiple stages, converting the light signal, which was originally below the detection threshold, into an electronic signal that can be recognized by an external terminal.

[0052] Specifically, when the sensor converts the optical signal into an electrical signal and transmits it to an external data processing terminal in real time, anti-interference processing of the transmission link is required. Shielded twisted-pair cable is used as the signal transmission cable, with the outer layer of the cable wrapped with a metal shield and grounded to block external electromagnetic signals from interfering with the transmission line. Signal filtering is performed at the signal output end of the sensor and the signal input end of the terminal to filter out high-frequency noise mixed in during transmission. Before transmission, the electrical signal is encoded to convert the original signal into an anti-interference encoding format. After receiving the signal, the terminal decodes it to restore the original signal.

[0053] Specifically, the method of using an adaptation algorithm to eliminate clutter generated by blood scattering is used to perform multi-frame superposition processing on the received image electrical signals. The specific process is as follows: frame synchronization is performed on the continuously acquired multi-frame image signals to determine the corresponding position of the same lesion area in the multi-frame; the signal intensity of the same position in different frames is compared, and stable signals with intensity fluctuations within a preset range are selected, while instantaneous strong scattering clutter caused by blood flow is eliminated; at the same time, by analyzing the grayscale characteristics of the lesion area and clutter, a preset grayscale threshold is set, and grayscale signals below the threshold are identified as clutter and filtered out, while only the effective grayscale signals of the lesion area exceeding the threshold are retained.

[0054] Specifically, when the external data processing terminal enhances the difference between the lesion area and normal tissue, it needs to adjust the algorithm parameters in combination with the tissue optical properties. The specific process is as follows: preset the optical reflection characteristics data of different vascular tissues (such as normal blood vessel walls, tumors, and calcifications); when processing images, the algorithm extracts the reflected light intensity features of each region in the current image, compares them with the preset data, and identifies suspected lesion areas; for the identified areas, automatically increase the grayscale difference between them and the surrounding normal tissues—if it is a suspected tumor area, enhance its texture contrast with the normal blood vessel wall; if it is a suspected calcification area, enhance its density contrast with the surrounding tissues, making the lesion features easier to identify clinically.

[0055] Specifically, the process of converting the processed signal into a visual image format for pixel arrangement according to the sensor's photosensitive area involves: determining the pixel coordinates corresponding to each electronic signal; mapping the intensity value of the electronic signal to the corresponding grayscale value; arranging the grayscale values ​​of the pixels in coordinate order to generate a bitmap format image, where the grayscale value of each pixel in the image corresponds to the intensity of reflected light from the lesion site; and simultaneously creating a multispectral image switching interface, which includes switching controls corresponding to three bands. When the doctor operates the controls, the system calls the image data of the corresponding band and refreshes the display area.

[0056] Specifically, after the endoscope completes one intravascular imaging, it is placed back into the test device simulating the vascular environment, and the imaging performance test steps are repeated to acquire images of the simulated lesion area. The acquired images are compared with the test images before use to check whether the image clarity and signal strength are consistent. If there is a significant difference, the endoscope is disassembled to check whether the components are loose or damaged, and then reassembled, calibrated, and tested again. After confirming that the performance is stable, the number of uses and the retest results are recorded as the basis for endoscope maintenance or replacement.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A multispectral imaging method for human electronic angiography, characterized in that, include: S1: The near-infrared spectrum of the target is converted into photoelectric signals using an ultra-miniature infrared-enhanced image sensor, and the imaging light inside the blood vessel is focused using a dedicated focusing lens; the overall specifications are calibrated to adapt to the interventional needs of most blood vessels in the human body, and the calibrated size data and photoelectric performance parameters are obtained. S2: Based on the need to avoid blood interference during intravascular imaging, three target spectral bands are preset; a multispectral light source corresponding to the target spectral bands is constructed, and each band is individually turned on, switched sequentially, or started in combination by configuring an independent controller; the light source is optically coupled to the endoscope body; The three target spectral bands preset based on the need to avoid blood interference during intravascular imaging are used to collect image information at different depths of the blood vessel: The first band of light, after shining on the blood vessel wall, is mostly reflected by the superficial structure and a small amount is absorbed by the deep tissue, reducing the absorption of light signals by hemoglobin and allowing more light signals reflected by the superficial structure of the blood vessel wall to reach the sensor; the second band of light can penetrate to the middle layer of the blood vessel wall, is reflected by the middle layer structure and returns, and is used to supplement the collection of light signals reflected by the middle layer structure of the blood vessel wall; the third band of light can penetrate the flowing blood, is reflected by the deep lesions of the blood vessel or the surface of the stent and returns through the blood, which is used to weaken the absorption and scattering of light signals by the blood, and allow the light signals reflected by the deep lesions of the blood vessel or the surface of the stent to penetrate the blood and reach the sensor; The independent controller configured for each band is used to adjust the light source according to the detection needs of different vascular lesions: the controller has a built-in storage mechanism that stores the correspondence between lesion type and band. When vascular calcification is detected, it receives an external calcification detection command, calls the corresponding control program in the storage mechanism, triggers the driving circuit of the third type of band light source, and turns on the third type of band light source alone. It uses the penetrability of this band to collect the density difference signal between the calcified area and the surrounding tissue. When vascular tumor is detected, it receives a tumor detection command, calls the corresponding program, alternately triggers the driving circuit of the first and second type of band light sources, switches on the first and second type of band light sources, and collects the reflected light difference signal between the tumor edge and the normal blood vessel wall. S3: With the aid of imaging equipment for positioning, the prepared endoscope is slowly pushed into the target blood vessel through the catheter path, and the pushing speed and direction are controlled until the tip reaches the vicinity of the lesion site; the light source and sensor are activated, and the light source is turned on in sequence according to the set spectral bands. The sensor synchronously collects the internal images of the blood vessel under the corresponding spectrum, and improves the photoelectric conversion effect by using its own infrared enhancement characteristics. After converting the light signal into an electrical signal, it is transmitted to the external data processing terminal in real time. S4: After receiving the image electrical signal, the external data processing terminal uses an adaptation algorithm to reduce noise and enhance contrast based on the image characteristics of different spectral bands, eliminates noise generated by blood scattering, and strengthens the difference between the lesion area and normal tissue; and converts the processed signal into a visual image format.

2. The method according to claim 1, characterized in that, The photoelectric signal conversion of the target's near-infrared spectrum is specifically performed as follows: the target's near-infrared light signal is filtered by the ultra-miniature infrared enhancement sensor to remove stray light in the non-target band; the remaining light signal enters the photosensitive array and is absorbed by the photosensitive unit and converted into charge carriers; the charge carriers form a weak current under the action of an electric field, which is then amplified by the internal circuit through multiple stages and converted into a stable electronic signal; at the same time, the electronic signal intensity output is matched with the receiving threshold of the external data processing terminal by adjusting the circuit gain.

3. The method according to claim 2, characterized in that, The specific process of adjusting the circuit gain to match the output electronic signal strength with the receiving threshold of the external data processing terminal is as follows: First, the signal receiving threshold range of the external data processing terminal is pre-obtained; then, in the electronic signal output stage, the current amplified electronic signal strength data is collected in real time; the collected signal strength is compared with the preset threshold range; if the signal strength is lower than the preset threshold, the amplification factor is increased through the circuit gain adjustment mechanism; if it is higher than the preset threshold, the amplification factor is decreased; the adjustment and comparison steps are repeated until the electronic signal strength stably falls within the threshold range; and finally, the final gain parameter is recorded.

4. The method according to claim 1, characterized in that, The dedicated focusing lens is used to accurately focus the near-infrared light reflected from the lesion site within the blood vessel onto the photosensitive area of ​​the sensor. The lens consists of multiple lenses with different curvatures. After the reflected light enters the lens, it is refracted sequentially through the lenses. The curvature parameters of the lenses are preset according to the distance between the lesion site and the lens. By adjusting the relative positions between the lenses, the focal point formed by the refracted light falls on the center of the photosensitive area of ​​the sensor, thus focusing all the reflected light from the lesion site into the photosensitive area.

5. The method according to claim 1, characterized in that, The overall calibration specifications are used to adjust the relative positions of the ultra-miniature infrared enhanced sensor and the dedicated focusing lens. The specific process is as follows: by comparing the axis deviation value of the dedicated focusing lens through laser beam projection, the lens angle and depth are gradually fine-tuned; a microscope is used to mark reference points to observe the alignment deviation between the center of the photosensitive area of ​​the ultra-miniature infrared enhanced sensor and the focal point of the lens, and the axes of the two are precisely aligned by displacement adjustment; at the same time, a precision measurement tool is used to obtain the overall specification data, and if it exceeds the preset range for adapting to most blood vessels in the human body, the size is adjusted to the standard range through controlled precision correction.

6. The method according to claim 1, characterized in that, The optical coupling between the light source and the endoscope body is used for alignment via fiber optic interface and lens refraction calibration. The specific process is as follows: clean the interface between the light source output end and the endoscope light transmission channel input end; align the center of the fiber optic interface with the center of the light transmission channel; adjust the lens angle at the light source output end so that the light signal output by the light source enters the light transmission channel inside the endoscope after being refracted by the lens; and fine-tune the lens angle until the light spot coverage area coincides with the imaging field of view of the sensor by detecting the shape of the light spot at the light outlet of the endoscope front end.

7. The method according to claim 1, characterized in that, The control of the pushing speed and direction is used in conjunction with the real-time display of the vascular path by the imaging equipment: the imaging equipment generates dynamic images of the inside of the blood vessel in real time, and the operator identifies the straight and curved segments of the blood vessel by observing the images; in the straight segment of the blood vessel, the endoscope is kept moving forward at a constant speed by the uniform speed drive mechanism of the pushing device; in the curved segment of the blood vessel, the operator uses the control lever to fine-tune the angle of the pushing device to slow down the pushing speed and change the curvature angle of the endoscope tip, so that the tip moves in the direction of the blood vessel curvature, avoiding the tip from colliding with the endothelial cells at the bend of the blood vessel and causing cell detachment; at the same time, the distance between the endoscope and the blood vessel wall is observed by the image, and the pushing direction is adjusted to advance the endoscope along the central axis of the blood vessel until the image shows that the tip has reached the vicinity of the lesion site.

8. The method according to claim 1, characterized in that, The infrared antireflection film on the sensor surface, which enhances photoelectric conversion efficiency by leveraging its own infrared enhancement characteristics, allows near-infrared light signals to pass through, reducing the reflection loss of light signals on the film surface. After the light signal enters the sensor, the photosensitive material in the sensitive photosensitive element absorbs the weak near-infrared light signal and generates charge carriers corresponding to the light intensity. The internal signal amplification circuit amplifies the weak current formed by the charge carriers in multiple stages, converting the light signal, which was originally below the detection threshold, into an electronic signal that can be recognized by an external terminal.

9. The method according to claim 1, characterized in that, The adaptive algorithm for eliminating clutter generated by blood scattering is used to perform multi-frame superposition processing on the received image electrical signals. The specific process is as follows: frame synchronization is performed on the continuously acquired multi-frame image signals to determine the corresponding position of the same lesion area in the multi-frame; the signal intensity of the same position in different frames is compared, and stable signals with intensity fluctuations within a preset range are selected, while instantaneous strong scattering clutter caused by blood flow is eliminated; at the same time, by analyzing the grayscale characteristics of the lesion area and clutter, a preset grayscale threshold is set, and grayscale signals below the threshold are identified as clutter and filtered out, retaining only the effective grayscale signals of the lesion area that exceed the threshold.

10. The method according to claim 1, characterized in that, The process of converting the processed signal into a visual image format for pixel arrangement according to the sensor's photosensitive area involves: determining the pixel coordinates corresponding to each electronic signal; mapping the intensity value of the electronic signal to the corresponding grayscale value; arranging the grayscale values ​​of the pixels in coordinate order to generate a bitmap format image, where the grayscale value of each pixel in the image corresponds to the intensity of reflected light from the lesion site; and simultaneously creating a multispectral image switching interface, which includes switching controls corresponding to three bands. When the doctor operates the controls, the system calls the image data of the corresponding band and refreshes the display area.

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