A blood vessel detection method and device

Abstract

The present invention provides a blood vessel detection method and device, comprising the following steps: irradiating light around and / or locally in a target area to form an irradiation area; obtaining a pickup image of the pickup area, with a specified spacing distance set between the pickup area and the irradiation area; synchronously moving the irradiation area and the pickup area, scanning the target area using the pickup area, and obtaining a development image of the target area. The technical solution of the present invention is adopted, by projecting light sources and capturing images on two adjacent and non-overlapping areas respectively, avoiding the method of directly capturing the light reflection on the skin surface, reducing the noise signal reflected by the epidermis, and improving the signal-to-noise ratio, so as to obtain a dark area after backscattering, and then the position and direction of deep blood vessels with high contrast can be observed.

Description

Technical Field

[0001] The present disclosure relates to the technical field of medical equipment, and in particular to a blood vessel detection method and device. Background Art

[0002] Currently, the equipment used for human blood vessel identification mostly uses near-infrared light in the 700-1000nm band, which has high scattering characteristics and large penetration depth in human skin, fat and muscle tissue. Near-infrared light is used to illuminate the surface of human skin, and cameras and other equipment are used to collect images reflected from the illuminated area. Because the hemoglobin in the blood vessels absorbs near-infrared light more than the surrounding tissues, the reflection of the blood vessels is less than that of other tissues, and a dark pattern that can indicate the direction of the blood vessels is produced in the reflected image captured by the camera.

[0003] The existing near-infrared blood vessel recognition solution, for blood vessels in deeper parts (blood vessel center depth>5mm), due to the attenuation of near-infrared light, the effective contrast signal is relatively weak, lower than the noise signal such as epidermal reflection, resulting in blurred blood vessel images or even no information. Therefore, the existing technology can only collect and identify images of shallow blood vessels. Summary of the invention

[0004] The present disclosure provides a blood vessel detection method and device, which avoids directly photographing the light reflected from the skin surface by projecting a light source and capturing images on two adjacent and non-overlapping areas respectively, thereby reducing the noise signal reflected from the epidermis and improving the signal-to-noise ratio to obtain a dark area after backscattering, thereby being able to observe the position and direction of deep blood vessels with high contrast.

[0005] In a first aspect, the present invention provides a blood vessel detection method, comprising the following steps: irradiating light around and / or locally a target area to form an irradiation area; acquiring a pickup image of the pickup area, wherein a prescribed spacing distance is set between the pickup area and the irradiation area; synchronously moving the irradiation area and the pickup area, scanning the target area using the pickup area, and obtaining a development image of the target area.

[0006] Furthermore, the target area is an area of ​​human or animal outer epidermal tissue where blood vessels exist.

[0007] Furthermore, obtaining a picked-up image of the picked-up area includes: photographing the picked-up area between the irradiated areas to obtain a picked-up image; and extracting an image of the picked-up area within the picked-up image to obtain a picked-up image.

[0008] Furthermore, the irradiation area is a plurality of strips, which are evenly arranged along the extension direction of the short side of the irradiation area; the picking area is the strip area in the center of the collection area, and the collection area is the area between the irradiation areas.

[0009] Furthermore, obtaining a developed image of the target area includes: obtaining a plurality of picked-up images by scanning the target area using a picked-up area; and obtaining a developed image by splicing the plurality of picked-up images according to relative positions of the picked-up images to the target area.

[0010] Furthermore, the irradiation area and the picking area are moved synchronously, and the moving distance at one time is the width of the picking area.

[0011] Furthermore, the shapes of the picking area and the irradiation area are strip, circle, square or ellipse, and the shapes of the picking area and the irradiation area are not required to be consistent.

[0012] According to a second aspect of the present invention, a blood vessel detection device is provided, comprising: a light source module, used to irradiate light on a target area to form an irradiation area; a pickup module, used to obtain a pickup image of the pickup area; a control module, used to synchronously move the light source module and the pickup module, and then synchronously move the irradiation area and the pickup area, and use the pickup area to scan the target area to obtain a development image of the target area; wherein the light source module and the pickup module are arranged adjacent to each other, and the light source module and the pickup module are respectively connected to the control processing module.

[0013] Furthermore, the light source module controls and adjusts the shape, area and distribution of the illumination area by means of a spatial modulation chip and a light source driver chip; the light source module controls and adjusts the light intensity of the illumination area by means of a light source driver chip.

[0014] Through the technical solution of the present invention, the target position where the near-infrared light is injected and the acquisition position of the acquired image are spatially separated by using the spatial light modulation method, and a vascular image with high contrast is acquired. The vascular image of the target position is obtained by sequential detection and shooting, and the entire vascular imaging image is obtained by sequential splicing and alignment, and finally the vascular image of the deeper position is obtained.

[0015] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, among which:

[0017] Figure 1 A flow chart showing a blood vessel detection method according to an embodiment of the present invention;

[0018] Figure 2 A diagram showing the area division of stripe modulation according to an embodiment of the present invention;

[0019] Figure 3 A diagram showing a stitching process of picked-up images according to an embodiment of the present invention;

[0020] Figure 4 A diagram showing the area division of circular modulation according to an embodiment of the present invention;

[0021] Figure 5 A schematic diagram showing the structure of a detection device according to an embodiment of the present invention is shown;

[0022] Figure 6 Another area division diagram of circular modulation according to an embodiment of the present invention is shown.

[0023] in, Figure 1-6 The corresponding relationship between the reference numerals and component names in the figure is:

[0024] 210 target area, 220 irradiation area, 230 picking area;

[0025] 310 a first developed image, 320 a second developed image, 330 a third developed image, N a Nth developed image;

[0026] 510 light source module, 520 picking module, 530 control module;

[0027] 610 moving path. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0029] In addition, the term "and / or" in this article is only a description of the association relationship between the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0030] The present invention proposes a novel method for acquiring blood vessel images deep in the skin, which uses spatial light modulation near-infrared projection to obtain a projection screen with alternating light and dark. The bright part is the irradiated part of the skin by the near-infrared light, and the dark part is the effective area for image acquisition. The final pickup area is the central area of ​​the effective area. By projecting light sources and capturing images on two adjacent and non-overlapping areas respectively, the method of avoiding direct shooting of light reflection on the skin surface can reduce the noise signal reflected by the epidermis, improve the signal-to-noise ratio, and obtain the dark area after backscattering, so as to observe the position and direction of deep blood vessels with high contrast.

[0031] Refer to the following Figure 1 To describe the first aspect of the present invention, a blood vessel detection method 100 is provided, comprising the following steps:

[0032] S110: irradiating light around and / or partially around the target area 210 to form an irradiation area 220;

[0033] S120: photographing the acquisition area between the irradiation areas 220 to obtain an acquisition image;

[0034] S130: extracting an image of a pickup area 230 in the captured image to obtain a pickup image;

[0035] S140: synchronously moving the irradiation area 220 and the pickup area 230;

[0036] S150: Scanning the target area 210 by using the pickup area 230 to obtain a plurality of pickup images;

[0037] S160 : splicing a plurality of picked-up images according to the relative positions of the picked-up images in the target area 210 to obtain a developed image of the target area 210 .

[0038] In the above embodiment, the target area 210 is an area of ​​the human or animal outer epidermal tissue where blood vessels exist, and the area at the elbow of the human arm is preferably used as the target area 210.

[0039] In this embodiment, the irradiation light uses near infrared light (700nm-1000nm), and the near infrared light is projected onto the skin surface at the elbow of the human arm as the irradiation area 220. Since near infrared light has high scattering characteristics and a large penetration depth in human skin, fat and muscle tissue, part of the near infrared light is reflected on the skin surface, and part of the near infrared light enters the subcutaneous tissue and is scattered to the subcutaneous tissue in the adjacent area. The hemoglobin in the blood has a higher absorption in the near infrared segment than the surrounding tissue, resulting in lower backscattering in the blood vessel area than in the surrounding area, thereby mapping the absorption contrast of the infrared light to the skin surface, forming a black shadow on the skin surface, and locating the position of the blood vessel through the black shadow.

[0040] In the above embodiment, when acquiring the picked-up image of the picking-up area 230, a prescribed spacing distance is set between the picking-up area 230 and the irradiation area 220. Specifically, the irradiation area 220 is adjacent to the picking-up area 230 and is spaced a certain distance apart, and the intensity and wavelength of the near-infrared light projected by the two irradiation areas 220 on both sides of the picking-up area 230 are ensured to be consistent, thereby ensuring that the scattered light on the left and right sides of the picking-up area 230 is consistent, thereby ensuring that the picking-up area 230 receives the least reflected near-infrared light from the skin, and setting a transition spacing distance increases the accuracy of the blood vessel position in the picking-up area 230. Because the hemoglobin in the blood has a much higher absorption than the surrounding tissue in the near-infrared band. When the near-infrared light scattered from the irradiation area 220 is projected onto the picking-up area 230, the area of ​​the blood vessel position will absorb more near-infrared light, and then reflect less near-infrared light than the surrounding tissue, forming a black shadow on the developed image.

[0041] In the above embodiment, the irradiation area 220 and the pickup area 230 are moved synchronously, and the moving distance at one time is the width of the pickup area 230. The synchronous movement ensures the spacing distance between the irradiation area 220 and the pickup area 230; when the target area 210 does not change, the moving distance is a fixed distance, preferably the width of a pickup area 230, and the fixed distance can be set to any preset distance according to the size and shape of the target area 210.

[0042] In the above embodiment, the acquisition area is set between adjacent irradiation areas 220, and the pickup area 230 is selected at the center of the acquisition area to obtain a pickup image. The irradiation area 220 selects irradiation lights of different shapes according to the area and shape of the target area 210, and irradiation areas 220 of different shapes are formed in the target area 210. In the acquisition images obtained by the acquisition areas between the irradiation areas 220 of different shapes, a pickup image of a specific shape is selected.

[0043] In this embodiment, the shapes of the pickup area 230 and the irradiation area 220 are strip, circular, square, or elliptical, and the shapes of the pickup area 230 and the irradiation area 220 are not required to be consistent.

[0044] like Figure 2As shown, the irradiation area 220 can be selected as a plurality of strips in the target area 210, and the plurality of strips are evenly spaced in the extension direction of the short side of the irradiation area 220 in the target area 210; the pickup area 230 is a strip area in the center of the collection area. During the shooting process, the irradiation area 220 and the pickup area 230 are moved synchronously with the same interval, and the moving distance of the synchronous movement is a fixed distance, and the fixed distance can be selected as the width of the pickup area 230, and the target area 210 is fully irradiated and photographed in turn to obtain a series of picked images, and the final picked images are spliced ​​to obtain the imaged image of the target area 210.

[0045] like Figure 3 As shown, the specific stitching method for stitching the final picked-up images is: selecting the picking-up area 230 at the center of the picking-up area 230 acquired for the first time as the first developed image 310, as shown in FIG. Figure 3 a; move the shooting position to perform a second acquisition, and obtain a second imaging image 320, as shown in FIG. Figure 3 b; sequentially move the shooting position to perform the third acquisition, and obtain the third imaging image 330, as shown in FIG. Figure 3 c; according to the target area 210, the image is taken n times in sequence to obtain the Nth image N; according to the position of each image in the target area 210, the image of the target area 210 can be obtained by seamlessly splicing, such as Figure 3 d. The displacement of each shooting movement is the width of the picking area 230; the picking areas 230 collected each time have no overlap, and the area of ​​the picking area is set to S, which is equal to the overall area of ​​the target area 210 multiplied by the number of shooting times N.

[0046] like Figure 4 As shown, the irradiation area 220 can be selected as multiple circular irradiation areas within the target area 210, and a collection area is formed between four adjacent circular irradiation areas. The center of the collection area is selected as the picking area 230. The picking area 230 can be in the shape of a circle, a rectangle, an ellipse, etc., to ensure that the picked image of the spliced ​​picking area 230 is equal to the overall area of ​​the target area 210.

[0047] The present invention utilizes spatial light modulation to spatially separate the target position where near-infrared light is injected from the acquisition position of the image, acquires a vascular image with high contrast, obtains the vascular image of the target position through sequential detection and shooting, and obtains the entire vascular imaging image by sequential splicing and alignment.

[0048] Refer to the following Figure 5To describe the second aspect of the present invention, a blood vessel detection device is provided, including: a light source module 510, used to irradiate light on the target area 210 to form an irradiation area 220; a picking module 520, used to obtain a picked-up image of the picking area 230; a control module 530, used to synchronously move the light source module 510 and the picking module 520, and then synchronously move the irradiation area 220 and the picking area 230, and use the picking area 230 to scan the target area 210 to obtain a development image of the target area 210; wherein the light source module 510 and the picking module 520 are adjacently arranged, and the light source module 510 and the picking module 520 are respectively connected to the control processing module 530.

[0049] In the above embodiment, the light source module is used to execute S110 to irradiate light on the target area 210 to form the irradiation area 220. The light source module 510 uses a spatial modulation near-infrared projection device to irradiate near-infrared rays to the target area 210 to form multiple irradiation areas 220, and relies on a spatial light modulation chip (DMD) or a liquid crystal device to control and adjust the shape, area and distribution of the irradiation area 220, and relies on a light source driver chip to adjust the illuminance of the irradiation area 220.

[0050] In the above embodiment, the pickup module 520 is used to execute S120 to obtain the picked-up image of the pickup area 230. The pickup module 520 uses a high-speed industrial camera, which is internally provided with a high-definition camera to capture the image of the target area 210 including the pickup area 230 to obtain the picked-up image; and transmit the picked-up image to the control module 530 at the same time.

[0051] In the above embodiment, the control module 530 is used to execute S130 to synchronously move the irradiation area 220 and the pickup area 230 with the same amplitude. The control module 530 includes a spatial light modulation system and a camera cooperative control system, which is used to receive the captured images of the pickup area 230 transmitted by the pickup module 520, and splice multiple groups of pickup areas 230 into a display image of the target area 210.

[0052] In this embodiment, the control module 530 includes a host computer and a slave computer. Preferably, the host computer is a PC host computer, which can be driven by an embedded system, an FPGA (field programmable gate array), a PLC (programmable logic controller) or other host systems. The host computer sends instructions to the slave computer, which generates a square wave waveform, and uses the square wave waveform as a synchronization signal to control the coordinated action of the light source module 510 and the pickup module 520.

[0053] In the above embodiment, the light source module 510 and the pickup module 520 are fixedly installed on the detection frame at a certain interval adjacent to each other. The detection frame is provided with a guide rail and a slider. The guide rail is fixedly installed on the detection frame at a position relative to the target area 210. The light source module 510 and the pickup module 520 are installed on the slider. The control module 530 is electrically connected to the slider to control the slider to move a certain displacement at a certain time, thereby realizing the synchronous movement of the light source module 510 and the pickup module 520, thereby completing the detection of the detection device and forming a blood vessel imaging image.

[0054] In this embodiment, the distance between the light source module 510 and the pickup module 520 is the spacing distance between the irradiation area 220 and the pickup area 230. The spacing distance is preset according to the shape and size of the target area 210 and the selection of the irradiation light source.

[0055] Because hemoglobin in the blood has a much higher absorption in the near-infrared band than the surrounding tissues, when the near-infrared rays scattered from the irradiation area 220 are projected into the pickup area 230, the blood vessel area in the pickup area 230 absorbs more near-infrared rays, and then reflects less near-infrared rays than the surrounding tissues, forming a black shadow on the development image, thereby forming a development image.

[0056] To obtain Figure 2 The strip-shaped modulated display image shown adopts one-dimensional spatial light modulation; the irradiation light and the pickup lens of the light source module 510 and the pickup module 520 are controlled by the control module 530, and are converted into a rectangle or a strip for detection. The moving tracks of the light source module 510 and the pickup module 520 move horizontally in sequence along the short side of the strip.

[0057] To obtain Figure 4 The circular modulated display image shown adopts two-dimensional spatial light modulation, and the irradiation light and the pickup lens of the light source module 510 and the pickup module 520 are controlled by the control module 530, and are all converted into a circle for detection. Each group of irradiation areas 220 is composed of four beams of light, and the irradiation shape of each beam of light is a circle, and the center position of the four beams of light is selected as the pickup area 230. The control module 530 controls the light source module 510 and the pickup module 520 to move along a fixed path until the pickup area 230 scans the area within all target areas 210.

[0058] Among them, Figure 6As shown, the picking area 230 is circular, and the shape of the irradiation area 220 can also be a regular pattern surrounding the picking area 230 arranged in a matrix, which can be a rectangle or a circle. The control module 530 controls the light source module 510 to step the irradiation area 220 along the moving path 610 to scan the target area 210, and the picking area 230 moves with the movement of the irradiation area 220. After the movement, the light source module 510 projects near-infrared rays on the next irradiation area, and the picking area 230 moves to the next picking area with the movement of the irradiation area 220, and the picking module 520 shoots and collects images until the picking area 230 scans the area within all target areas 210.

[0059] When the shape of the pickup area 230 is circular, the above detection operation will produce overlapping detection. There is an overlapping shot between the acquisition image shot this time and the acquisition image shot next time. When stitching the pickup images, the control module 530 performs optimal processing on the overlapping parts of the pickup images, selects the image with high vascularity and high signal-to-noise ratio in the overlapping images as part of the development image, and stitches the images picked each time according to their relative positions in the target area 210 to obtain the development image.

[0060] When the technical solution of the present invention is used for blood vessel detection, the following technical effects are achieved:

[0061] The interval setting between the irradiation area and the pickup area reduces the total amount of near-infrared projection in the target area, reduces the infrared reflection on the skin surface, improves the signal-to-noise ratio, makes the blood vessel imaging clearer, and enables the detection and imaging of blood vessels in deeper parts;

[0062] Through reasonable spatial modulation settings, sufficient near-infrared rays injected from the irradiation area can be obtained in the image acquisition area, and then backscattered inside the human body to form a vascular imaging image. In this imaging image, the position of blood vessels with a certain depth can be located;

[0063] By using a detection device consisting of a spatial light modulation light source, a high-definition camera and a collaborative control system to detect blood vessels at a certain depth, multiple images of different near-infrared injection sites and image acquisition sites can be quickly collected, and the extraction and fusion reproduction of effective blood vessel images at the image acquisition site can be completed.

[0064] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should be aware that the present disclosure is not limited by the order of the actions described, because according to the present disclosure, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required by the present disclosure.

[0065] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the described module can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0066] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit this.

[0067] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A blood vessel detection method, characterized in that: The following steps are involved: irradiating light around and / or locally at the target area to form an irradiation area; Acquire a picked-up image of a picked-up area, wherein a prescribed spacing distance is set between the picked-up area and the irradiated area; The irradiation area and the pickup area are synchronously moved, and the target area is scanned by using the pickup area to obtain a development image of the target area. The step of obtaining the developed image of the target area comprises: By scanning the target area using the pickup area, a plurality of the pickup images are obtained, According to the relative position of the picked-up image in the target area, a plurality of the picked-up images are spliced ​​to obtain the developed image.

2. The method according to claim 1, characterized in that The target area is an area of ​​human or animal outer epidermal tissue where blood vessels exist.

3. The method according to claim 1, characterized in that The step of acquiring the picked-up image of the picked-up area comprises: photographing the acquisition area between the irradiation areas to obtain an acquisition image; An image of a pickup area within the acquired image is extracted to obtain a pickup image.

4. The method according to claim 3, characterized in that The irradiation area is in the shape of a plurality of strips, which are evenly arranged along the extension direction of the short side of the irradiation area; The pickup area is a strip-shaped area at the center of the collection area, and the collection area is an area between the irradiation areas.

5. The method according to claim 1, characterized in that The irradiation area and the pickup area are synchronously moved, and a moving distance thereof is equal to a width of the pickup area.

6. The method according to claim 1, characterized in that The shapes of the pickup area and the irradiation area are strip, circle, square or ellipse, and the shapes of the pickup area and the irradiation area are not required to be consistent.

7. A blood vessel detection device, characterized in that: include: A light source module, used for irradiating light on a target area to form an irradiation area; A picking module, used for acquiring a picking image of a picking area, wherein the irradiation area and the picking area are adjacent to each other and have no overlap; a control module, used for synchronously moving the light source module and the pickup module, and then synchronously moving the irradiation area and the pickup area, and using the pickup area to scan the target area to obtain a development image of the target area, The step of obtaining the developed image of the target area comprises: By scanning the target area using the pickup area, a plurality of the pickup images are obtained, According to the relative position of the picked-up image in the target area, a plurality of the picked-up images are spliced ​​to obtain the developed image; wherein, The light source module is disposed adjacent to the pickup module, and the light source module and the pickup module are connected to the control module respectively.

8. The device according to claim 7, characterized in that The light source module controls and adjusts the shape, area and distribution of the irradiation area by means of a spatial modulation chip and a light source driving chip; The light source module relies on the light source driving chip to control and adjust the light intensity of the irradiation area.

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