A brain-computer interface device

Abstract

This invention relates to a brain-computer interface device, comprising: a laser emitting laser light and outputting it to an optical fiber coupling device; the optical fiber coupling device splitting the laser light into a probe light and a first coherent light; a first multimode fiber connected at one end to the optical fiber coupling device, transmitting the probe light to a target object to generate scattered light carrying the brain blood flow signal of the target object; a second multimode fiber transmitting the scattered light to a beam splitter; a third multimode fiber connected at one end to the optical fiber coupling device and at the other end to a laser shaping device, transmitting the first coherent light to the laser shaping device; the laser shaping device shaping the first coherent light and outputting it to the beam splitter; the beam splitter performing optical wave interference superposition of the scattered light and the shaped first coherent light to generate an output light signal; and a camera acquiring the output light signal and transmitting it to an external processing device for analysis and processing to obtain speckle image data.

Description

Technical Field

[0001] This invention relates to the field of brain-computer interface technology, and more particularly to a brain-computer interface device. Background Technology

[0002] Brain-computer interface (BCI) refers to a direct or indirect connection created between the brain (or a culture of brain cells) of a person or animal and an external device, enabling information exchange between the brain and the device. Specifically, BCI technology uses an external device to capture brain signals and convert them into electrical signals, thereby enabling the transmission and control of information between the brain and the external device.

[0003] According to the principle of neurovascular coupling, the blood flow state of the brain will respond locally to local changes in its functional activities. Therefore, the brain activity state of the subject being tested is related to changes in cerebral blood flow, and the degree of brain activity of the subject being tested can be determined by observing the blood flow state of the brain.

[0004] Among the various methods for detecting cerebral blood flow, the most commonly used is the non-invasive method using near-infrared light scattering with non-embedded devices. However, when detecting changes in blood flow in the target body, the number of photons carrying the cerebral blood flow signal collected by commonly used non-embedded devices is very low. Therefore, it is difficult to collect enough photons for signal analysis, resulting in poor image clarity, affecting the final detection results, and reducing the accuracy of the detection. In addition, photoacoustic imaging is also a method for detecting cerebral blood flow. Due to its greater detection depth, it can effectively achieve deep imaging of the distribution of cerebral blood flow. However, the main drawback of photoacoustic imaging technology is that the imaging process may be affected by the mismatch of sound velocity between tissues, which may distort the imaging results and reduce the detection accuracy.

[0005] The current solution is to use a single-photon counter to collect photons carrying cerebral blood flow signals. Single-photon counters have high sensitivity and can detect single photons under low light levels. They can collect enough photons for signal analysis, which improves the accuracy of detection. However, since single-photon counters need to process photons one by one, it takes a long time to obtain an image that reflects changes in cerebral blood flow, resulting in excessive imaging processing time and reduced detection efficiency.

[0006] Therefore, designing a new brain-computer interface device to improve the accuracy of examination results and detection efficiency is of great importance. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of existing technologies by providing a brain-computer interface device. Using the brain-computer interface device provided by this invention improves the accuracy of examination results and detection efficiency.

[0008] To achieve the above objectives, the present invention provides a brain-computer interface device, the brain-computer interface device comprising: a laser, an optical fiber coupling device, a laser shaping device, a beam splitter, a camera, a headgear, a first multimode optical fiber, a second multimode optical fiber, and a third multimode optical fiber;

[0009] The laser is used to emit laser light and output it to the fiber optic coupling device;

[0010] The fiber optic coupling device is used to split the laser into two paths: the first path is the probe light, and the second path is the first coherent light.

[0011] The headgear is used to fix the first multimode optical fiber and the second multimode optical fiber onto the object to be tested.

[0012] One end of the first multimode optical fiber is connected to the optical fiber coupling device, and the other end is fixed to the first position of the headgear by the first silicone clasp; the first multimode optical fiber is used to transmit the probe light to the object to be detected, and the probe light is scattered when it shines on the object to be detected, generating scattered light carrying the brain blood flow signal of the object to be detected;

[0013] One end of the second multimode optical fiber is fixed to the second position of the headgear by a second silicone clasp; the second multimode optical fiber is used to transmit the scattered light carrying the cerebral blood flow signal of the subject to be detected to the beam splitter;

[0014] One end of the third multimode fiber is connected to the fiber coupling device, and the other end is connected to the laser shaping device; the third multimode fiber is used to transmit the first coherent light to the laser shaping device.

[0015] The laser shaping device is used to adjust the intensity of the first coherent light to form a second coherent light, to perform beam homogenization processing on the second coherent light to form a third coherent light, and to perform beam diameter adjustment processing on the third coherent light to form a fourth coherent light; and to output the fourth coherent light to the beam splitter.

[0016] The beam splitter is used to perform optical wave interference superposition of the scattered light transmitted through the second multimode fiber and the fourth coherent light to generate an output optical signal;

[0017] The camera is used to collect the output light signal and transmit it to an external processing device, which then analyzes and processes the output light signal to obtain speckle image data.

[0018] Preferably, the fiber optic coupling device includes: a focusing lens and a multimode fiber coupler;

[0019] The focusing lens is used to focus the laser emitted by the laser.

[0020] The multimode fiber coupler is used to split the focused laser into probe light and first coherent light.

[0021] Preferably, the power of the probe light accounts for 50%-90% of the power of the laser; and the power of the first coherent light accounts for 10%-50% of the power of the laser.

[0022] Preferably, the core diameters of the first multimode fiber, the second multimode fiber, and the third multimode fiber are all greater than 300 μm.

[0023] Preferably, the brain-computer interface device further includes: a first fiber optic collimator;

[0024] One end of the first fiber collimator is connected to the first multimode fiber, and the other end is fixed to the first silicone clasp; the first fiber collimator is used to collimate the probe light output from the first multimode fiber.

[0025] Preferably, the brain-computer interface device further includes a second fiber optic collimator;

[0026] One end of the second fiber collimator is connected to one end of the second multimode fiber, and the other end is fixed to the second silicone clasp; the second fiber collimator is used to expand the receiving range of the second multimode fiber for the scattered light of the brain blood flow signal carrying the subject to be detected.

[0027] Preferably, the laser shaping device comprises, in sequence: an intensity-adjusting lens group, a Powell prism, and an adjustable grating;

[0028] The light intensity adjusting lens group is used to adjust the light intensity of the first coherent light to form the second coherent light;

[0029] The Powell prism is used to homogenize the second coherent light to form the third coherent light.

[0030] The adjustable grating is used to process the beam diameter of the third coherent light to form the fourth coherent light.

[0031] Preferably, the brain-computer interface device further includes: a third fiber optic collimator;

[0032] One end of the third fiber collimator is connected to the other end of the second multimode fiber, and is used to collimate the scattered light output from the second multimode fiber.

[0033] Preferably, the brain-computer interface device further includes: a cylindrical lens;

[0034] The cylindrical lens is located between the beam splitter and the camera, and is used to focus the output light signal from the beam splitter.

[0035] Preferably, the camera is a line scan camera.

[0036] The brain-computer interface device provided in this embodiment of the invention improves detection accuracy by using a large-core diameter multimode optical fiber to collect more output light signals. Furthermore, it adjusts the intensity of the first coherent light using a laser shaping device to form a second coherent light, homogenizes the second coherent light to form a third coherent light, and adjusts the diameter of the third coherent light to form a fourth coherent light. This shaping process not only avoids damage to the camera caused by excessive light intensity, but also eliminates clutter and improves the output light signal when the fourth coherent light is subsequently superimposed with the scattered light from the brain blood flow signal carrying the subject of the invention through optical wave interference. The signal-to-noise ratio of the output light signal improves the accuracy of the detection results. Furthermore, using a cylindrical lens focusing beam splitter not only reduces energy loss in the output light signal, allowing the camera to receive more output light signals and improving detection accuracy, but also limits the beam diameter of the output light signal to a preset range. This allows for image acquisition at a lower resolution during subsequent processing of the output light signal, reducing processing time and improving detection efficiency. Additionally, using a camera instead of a single-photon counter results in faster acquisition speeds, effectively reducing output light signal processing time, thus improving detection efficiency and significantly lowering the cost of brain-computer interface devices. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the structure of a brain-computer interface device provided in an embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of the structure of the headgear provided in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the structure of the laser shaping device provided in an embodiment of the present invention;

[0040] Figure 4 A flowchart illustrating the installation method of the brain-computer interface device provided in an embodiment of the present invention;

[0041] Figure 5 This is a flowchart illustrating the operation method of the brain-computer interface device provided in an embodiment of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0043] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0044] First, this invention provides a brain-computer interface device. Figure 1 This is a schematic diagram of the brain-computer interface device provided in an embodiment of the present invention, such as... Figure 1 The brain-computer interface device provided in this embodiment of the invention includes: a laser 1, an optical fiber coupling device 2, a laser shaping device 3, a beam splitter 4, a camera 5, a headgear 6, a first multimode optical fiber 7, a second multimode optical fiber 8, and a third multimode optical fiber 9.

[0045] Laser 1 is used to emit laser light. As a light source, the light source in this invention adopts a near-infrared laser, which is called the "brain window". That is, the laser emits near-infrared light. Considering the test object's tolerance to laser light, the laser power of the selected near-infrared light is between 100mW and 300mW. Before the laser is emitted, the collimation system in the laser will collimate it so that the diameter of the laser beam is between 1mm and 3mm.

[0046] The fiber optic coupling device 2 receives the laser emitted by the laser 1 and performs beam splitting. Specifically, the fiber optic coupling device 2 splits the laser into two paths: the first path is the probe light, and the second path is the first coherent light.

[0047] The head cover 6 is used to fix the first multimode fiber 7 and the second multimode fiber 8 onto the object to be tested. Figure 2 This is a schematic diagram of the headgear provided in an embodiment of the present invention. The headgear 6 has multiple silicone retaining rings, which respectively fix the first multimode optical fiber 7 and the second multimode optical fiber 8 at different positions on the headgear 6. Specifically,

[0048] One end of the first multimode fiber is connected to the fiber coupling device 2, and the other end is fixed to the first position of the headgear 6 by the first silicone clasp 61; the first multimode fiber 7 is used to transmit the probe light to the object to be tested. When the probe light shines on the object to be tested, it is scattered, generating scattered light carrying the brain blood flow signal of the object to be tested.

[0049] One end of the second multimode fiber 8 is fixed to the second position of the headgear by the second silicone clasp 62; the second multimode fiber 8 is used to transmit the scattered light carrying the brain blood flow signal of the subject to be tested to the beam splitter 4.

[0050] One end of the third multimode fiber 9 is connected to the fiber coupling device 2, and the other end is connected to the laser shaping device 3; the third multimode fiber is used to transmit the first coherent light to the laser shaping device 3.

[0051] Specifically, the power of the probe light accounts for 50%-90% of the laser power, while the power of the first coherent light accounts for 10%-50% of the laser power. That is, 50%-90% of the laser power serves as the probe light for the object being tested. When this probe light strikes the object, it is scattered, generating scattered light carrying the brain blood flow signal of the object. The remaining 10%-50% of the laser power serves as the first coherent light, used for subsequent optical wave interference superposition with the scattered light within beam splitter 4 to remove clutter when generating the output optical signal. Because clutter interference is filtered out, the signal-to-noise ratio of the output optical signal is improved.

[0052] It should be noted that in practical applications, the number of the first multimode fiber 7 and the second multimode fiber 8 is set according to the requirements. There is at least one first multimode fiber 7 and at least one second multimode fiber 8. The number of second multimode fibers 8 is not less than the number of first multimode fibers 7.

[0053] The number of silicone clasps on the headgear 6 is also set as needed, wherein the number of first silicone clasps 61 is not less than the number of first multimode optical fibers 7, and the number of second silicone clasps 62 is not less than the number of second multimode optical fibers 8.

[0054] The laser shaping device 3 is used to adjust the intensity of the first coherent light to form the second coherent light, to homogenize the second coherent light to form the third coherent light, and to adjust the beam diameter of the third coherent light to generate the fourth coherent light; and to output the fourth coherent light to the beam splitter 4. Specifically, Figure 3 This is a schematic diagram of the structure of the laser shaping device provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the laser shaping device 3 sequentially includes: an intensity-adjusting lens group 31, a Powell prism 32, and an adjustable grating 33; wherein,

[0055] The intensity adjustment lens group 31, consisting of an adjustable baffle 311 and two lenses 312, is used to adjust the intensity of the first coherent light to form the second coherent light. Adjusting the intensity of the first coherent light avoids damage to the camera 5 caused by excessive light intensity.

[0056] The Powell prism 32 is used to homogenize the second coherent light to form the third coherent light. This process makes the intensity of the second coherent light more uniform, and beam homogenization is beneficial for subsequent optical wave interference superposition with the scattered light in the beam splitter 4 to generate the output optical signal, thereby further improving the signal-to-noise ratio of the output optical signal.

[0057] The adjustable grating 33 is used to adjust the beam diameter of the third coherent light to form the fourth coherent light. By adjusting the beam diameter of the third coherent light, the excessive mismatch between the beam diameter of the formed fourth coherent light and the beam diameter of the scattered light entering the beam splitter 4 is avoided, which would interfere with the detection results and affect the accuracy of the detection results.

[0058] Beam splitter 4 is used to perform optical wave interference superposition of the scattered light transmitted from the second multimode fiber and the fourth coherent light to generate an output optical signal.

[0059] Camera 5 is used to acquire the above-mentioned output light signal and to analyze and process the output light signal to obtain speckle image data.

[0060] The object of this invention is to observe the changes in blood flow during continuous movement in the brain of the subject to be tested. As is well known, blood flow is relatively fast, so the signals to be acquired also change rapidly. In order to quickly acquire the active state of the brain of the subject to be tested, the camera used in this application is a linear array camera, specifically a linear array CCD camera or a linear array CMOS camera.

[0061] In one example, the fiber optic coupling device 2 includes a focusing lens and a multimode fiber coupler. The laser emitted by the laser 1 enters the fiber optic coupling device 2. To reduce the energy loss of the laser, the laser entering the fiber optic coupling device 2 is first focused by the focusing lens and then enters the multimode fiber coupler. It is then split into two paths. One path is the probe light of the object to be tested, which is transmitted to the object to be tested through the first multimode fiber 7. The probe light irradiates the object to be tested and is scattered, generating scattered light carrying the brain blood flow signal of the object to be tested. The scattered light enters the beam splitter 4 through the second multimode fiber 8.

[0062] In another example, the brain-computer interface device further includes a first fiber collimator (not shown) and a second fiber collimator (not shown); one end of the first fiber collimator is connected to the first multimode fiber 7, and the other end is fixed to the first silicone clasp 61; the first fiber collimator is used to collimate the probe light output from the first multimode fiber 7; one end of the second fiber collimator is connected to the second multimode fiber 8, and the other end is fixed to the second silicone clasp 62; the second fiber collimator is used to expand the receiving range of the second multimode fiber for the scattered light of the brain blood flow signal carrying the subject to be tested.

[0063] In yet another example, such as Figure 1 As shown, the brain-computer interface device also includes a third fiber collimator 10, one end of which is connected to the other end of the second multimode fiber 8. This collimator is used to collimate the scattered light output from the second multimode fiber 8, so that the scattered light that finally enters the beam splitter 4 is close to the beam diameter of the fourth coherent light output from the laser shaping device 3. This facilitates the subsequent optical wave interference superposition between the two to remove clutter.

[0064] In another example, such as Figure 1 As shown, the brain-computer interface device also includes a cylindrical lens 11, located between the beam splitter 4 and the camera 5, used to focus the output light signal output by the beam splitter 4. This not only reduces the energy loss of the output light signal, allowing the camera to receive more output light signals and improve the accuracy of the detection results, but also limits the beam diameter of the output light signal to a preset range, so that images can be obtained with a small resolution when processing the output light signal, thereby reducing the processing time for the output light signal and improving detection efficiency.

[0065] It should also be noted that, in order to receive more output optical signals, the core diameters of the first multimode fiber 7, the second multimode fiber 8, and the third multimode fiber 9 used in this invention are all greater than 300 μm. Multimode fibers can transmit multiple modes of optical signals and have stronger resistance to external electromagnetic interference than single-mode fibers. Furthermore, the large core diameters of the multimode fibers used in this invention enable them to receive more output optical signals, effectively improving the accuracy of the detection results of the brain-computer interface device. In addition, the large diameter also makes multimode fibers less prone to damage than single-mode fibers, easier to install and maintain, and reduces the cost of the brain-computer interface device.

[0066] In addition, the first, second, and third fiber collimators mentioned above can also be replaced by lens groups to achieve the corresponding beam expansion or collimation effects.

[0067] Single-photon counters are used to collect photons of brain blood flow signals from the target organism to improve the accuracy of existing detection methods due to their strong detection capability for weak light signals. However, their acquisition speed is relatively slow, affecting detection efficiency, and the equipment cost of single-photon counters is relatively high, resulting in high detection costs. Compared to single-photon counters, cameras not only have higher signal processing speeds but also lower equipment costs, making it possible for cameras to replace single-photon counters as signal acquisition devices. To make cameras compatible with the brain-computer interface device of this invention, the following measures are taken:

[0068] First, the coherent light is shaped by the laser shaping device 3. Specifically, the laser shaping device 3 adjusts the intensity of the first coherent light to form the second coherent light, performs beam homogenization on the second coherent light to form the third coherent light, and adjusts the beam diameter of the third coherent light to form the fourth coherent light. The shaped fourth coherent light is then output to the beam splitter.

[0069] Among them, the light intensity adjustment avoids damage to the camera caused by excessive light intensity; the beam homogenization process is used to homogenize the Gaussian distribution of the beam, thereby homogenizing the subsequent interference and improving the signal-to-noise ratio of the output light signal; the beam diameter adjustment process ensures that the beam diameters of the final fourth coherent light and the scattered light entering the beam splitter 4 are not excessively mismatched, which facilitates better removal of clutter when the two light waves interfere.

[0070] Second, the second collimator is first used to expand the receiving range of the scattered light carrying the brain blood flow signal of the subject to be detected by the second multimode fiber. Then, the third collimator is used to collimate the scattered light carrying the brain blood flow signal of the subject to be detected. This not only allows more scattered light carrying the brain blood flow signal of the subject to be detected to be collected, but also makes the beam diameter of the scattered light comparable to the beam diameter of the fourth coherent light. This facilitates better removal of clutter when the scattered light and the fourth coherent light interfere with each other in the beam splitter 4.

[0071] Third, a large-core diameter multimode fiber is used to collect more scattered light carrying the brain blood flow signal of the subject being tested, so that the subsequent camera 5 can collect more output light signals.

[0072] Fourth, the use of cylindrical lens 11 to focus the output light signal output from beam splitter 4 can not only reduce the energy loss of the output light signal, allowing camera 5 to collect more output light signals, but also limit the beam diameter of the output light signal to a preset range, so that images can be obtained with low resolution when processing the output light signal, thereby reducing the processing time for the output light signal.

[0073] The brain-computer interface device provided in this invention, on the one hand, can collect more output light signals and improve detection accuracy by using a multimode fiber with a large core diameter; on the other hand, it adjusts the intensity of the first coherent light to form a second coherent light through a laser shaping device, performs beam homogenization processing on the second coherent light to form a third coherent light, and adjusts the beam diameter of the third coherent light to form a fourth coherent light. The above shaping process not only avoids damage to the camera caused by excessive light intensity, but also, when the fourth coherent light is subsequently superimposed with the scattered light carrying the brain blood flow signal of the subject to be detected to generate the output light signal, it not only eliminates the influence of clutter but also improves the output accuracy. The signal-to-noise ratio of the optical signal improves the accuracy of the detection results. Furthermore, utilizing the cylindrical lens focusing beam splitter not only reduces energy loss in the output optical signal, allowing the camera to receive more output optical signals and further improving accuracy, but also limits the beam diameter of the output optical signal to a preset range. This enables subsequent processing of the output optical signal at a lower resolution, reducing processing time and improving detection efficiency. Moreover, replacing the single-photon counter with a camera results in faster acquisition speeds, effectively reducing output optical signal processing time, thus improving detection efficiency and significantly lowering the cost of brain-computer interface (BCI) devices. Therefore, the BCI provided by this invention not only improves the accuracy and efficiency of detection results but also reduces the cost of BCI devices.

[0074] The following is a detailed introduction to the use of EEG interface devices, including... Figure 4 This is a flowchart illustrating the installation method of the brain-computer interface device provided in this embodiment of the invention. Figure 4 The method steps shown are for installing the EEG interface device:

[0075] Step 101: Put the headgear on the head of the object to be tested.

[0076] Step 102: Connect one end of the first multimode optical fiber to one end of the optical fiber coupling device, and fix the other end to the first position of the headgear using the first silicone clasp.

[0077] Step 103: Fix one end of the second multimode fiber to the second position of the headgear using the second silicone clip.

[0078] Step 104: Connect one end of the third multimode fiber to one end of the laser coupling device and the other end to one end of the laser shaping device.

[0079] Step 105: Connect one end of the input of the beam splitter to the other end of the second multimode fiber, connect the other end to the other end of the laser shaping device, and connect the output to the camera.

[0080] Step 106: Connect the laser to the other end of the fiber optic coupling device.

[0081] Figure 5 This is a schematic flowchart of the operation method of the brain-computer interface device provided in this embodiment of the invention. After installing the brain-computer interface device according to steps 101-106, ... Figure 5 The steps shown are for operating the brain-computer interface device:

[0082] Step 201: Turn on the laser and emit laser light. The laser light with 80% power is used as the probe light and is transmitted to the object to be tested by the first multimode fiber. The probe light irradiates the object to be tested and is scattered, generating scattered light carrying the brain blood flow signal of the object to be tested. The scattered light is captured by the third multimode fiber and transmitted to the beam splitter.

[0083] Step 202: The 20% power laser light is used as the first coherent light and is transmitted to the laser shaping device by the third multimode fiber. The laser shaping device adjusts the intensity of the first coherent light to form the second coherent light, performs beam homogenization processing on the second coherent light to form the third coherent light, and performs beam diameter adjustment processing on the third coherent light to form the fourth coherent light. The fourth coherent light is then output to the beam splitter.

[0084] Step 203: The scattered light and the fourth coherent light are superimposed by optical wave interference in the beam splitter to generate the output optical signal;

[0085] Step 204: Turn on the camera, collect the output light signal and transmit it to an external processing device, which then analyzes and processes the output light signal to obtain speckle image data.

[0086] The functions performed by the components involved in the usage method provided in the embodiments of the present invention have been described in detail in the embodiments of the brain-computer interface device described above, so they will not be repeated here.

[0087] It should be noted that the above method is only one specific execution method. In actual application of the device, the above steps may not be performed in the same order.

[0088] The brain-computer interface device provided in this invention, on the one hand, can collect more output light signals and improve detection accuracy by using a multimode fiber with a large core diameter; on the other hand, it adjusts the intensity of the first coherent light to form a second coherent light through a laser shaping device, performs beam homogenization processing on the second coherent light to form a third coherent light, and adjusts the beam diameter of the third coherent light to form a fourth coherent light. The above shaping process not only avoids damage to the camera caused by excessive light intensity, but also, when the fourth coherent light subsequently undergoes optical wave interference superposition with the scattered light carrying the brain blood flow signal of the subject to be detected to generate the output light signal, it not only eliminates the influence of clutter but also improves the output... The signal-to-noise ratio of the optical signal improves the accuracy of the detection results. Furthermore, utilizing the cylindrical lens focusing beam splitter not only reduces energy loss in the output optical signal, allowing the camera to receive more output optical signals and further improving accuracy, but also limits the beam diameter of the output optical signal to a preset range. This enables subsequent processing of the output optical signal at a lower resolution, reducing processing time and improving detection efficiency. Moreover, replacing the single-photon counter with a camera results in faster acquisition speeds, effectively reducing output optical signal processing time, thus improving detection efficiency and significantly lowering the cost of brain-computer interface (BCI) devices. Therefore, the BCI provided by this invention not only improves the accuracy and efficiency of detection results but also reduces the cost of BCI devices.

[0089] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0090] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0091] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A brain-computer interface device, characterized in that, The brain-computer interface device includes: a laser, an optical fiber coupling device, a laser shaping device, a beam splitter, a camera, a headgear, a first multimode optical fiber, a second multimode optical fiber, and a third multimode optical fiber; The laser is used to emit laser light and output it to the fiber optic coupling device; The fiber optic coupling device is used to split the laser into two paths: the first path is the probe light, and the second path is the first coherent light. The headgear is used to fix the first multimode optical fiber and the second multimode optical fiber onto the object to be tested. One end of the first multimode optical fiber is connected to the optical fiber coupling device, and the other end is fixed to the first position of the headgear by the first silicone clasp; the first multimode optical fiber is used to transmit the probe light to the object to be detected, and the probe light is scattered when it shines on the object to be detected, generating scattered light carrying the brain blood flow signal of the object to be detected; One end of the second multimode optical fiber is fixed to the second position of the headgear by a second silicone clasp; the second multimode optical fiber is used to transmit the scattered light carrying the cerebral blood flow signal of the subject to be detected to the beam splitter; One end of the third multimode fiber is connected to the fiber coupling device, and the other end is connected to the laser shaping device; the third multimode fiber is used to transmit the first coherent light to the laser shaping device. The laser shaping device is used to adjust the intensity of the first coherent light to form a second coherent light, to perform beam homogenization processing on the second coherent light to form a third coherent light, and to perform beam diameter adjustment processing on the third coherent light to form a fourth coherent light; and to output the fourth coherent light to the beam splitter. The beam splitter is used to perform optical wave interference superposition of the scattered light transmitted through the second multimode fiber and the fourth coherent light to generate an output optical signal; The camera is used to collect the output light signal and transmit it to an external processing device, which then analyzes and processes the output light signal to obtain speckle image data.

2. The brain-computer interface device according to claim 1, characterized in that, The fiber optic coupling device includes: a focusing lens and a multimode fiber coupler; The focusing lens is used to focus the laser emitted by the laser. The multimode fiber coupler is used to split the focused laser into probe light and first coherent light.

3. The brain-computer interface device according to claim 1, characterized in that, The power of the probe light accounts for 50%-90% of the power of the laser; the power of the first coherent light accounts for 10%-50% of the power of the laser.

4. The brain-computer interface device according to claim 1, characterized in that, The core diameters of the first multimode fiber, the second multimode fiber, and the third multimode fiber are all greater than 300 μm.

5. The brain-computer interface device according to claim 1, characterized in that, The brain-computer interface device further includes: a first fiber optic collimator; One end of the first fiber collimator is connected to the first multimode fiber, and the other end is fixed to the first silicone clasp; the first fiber collimator is used to collimate the probe light output from the first multimode fiber.

6. The brain-computer interface device according to claim 1, characterized in that, The brain-computer interface device further includes: a second fiber optic collimator; One end of the second fiber collimator is connected to one end of the second multimode fiber, and the other end is fixed to the second silicone clasp; the second fiber collimator is used to expand the receiving range of the second multimode fiber for the scattered light of the brain blood flow signal carrying the subject to be detected.

7. The brain-computer interface device according to claim 1, characterized in that, The laser shaping device comprises, in sequence: an intensity modulation lens group, a Powell prism, and an adjustable grating; The light intensity adjusting lens group is used to adjust the light intensity of the first coherent light to form the second coherent light; The Powell prism is used to homogenize the second coherent light to form the third coherent light. The adjustable grating is used to adjust the beam diameter of the third coherent light to form the fourth coherent light.

8. The brain-computer interface device according to claim 1, characterized in that, The brain-computer interface device also includes: a third fiber optic collimator; One end of the third fiber collimator is connected to the other end of the second multimode fiber, and is used to collimate the scattered light output from the second multimode fiber.

9. The brain-computer interface device according to claim 1, characterized in that, The brain-computer interface device also includes: a cylindrical lens; The cylindrical lens is located between the beam splitter and the camera, and is used to focus the output light signal from the beam splitter.

10. The brain-computer interface device according to claim 1, characterized in that, The camera is a line scan camera.

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