Fast Automatic Optical Power Calibration Method and Device Based on fNIRS Equipment

Abstract

The present invention discloses a fast and automated optical power calibration method based on fNIRS equipment, comprising: determining an initial optical power level of 2 N‑1 ‑1, where N represents the power corresponding to the total optical power level of the light source; based on the initial optical power level, the optical power level is iteratively calibrated at intervals of 2n, where n is an integer and is less than N‑1; during the iterative calibration process, when the number of calibrations is less than or equal to N‑1, the maximum voltage of all probes around each light source obtained within the first preset time length is compared with the first voltage threshold, and the optical power level is adjusted according to the comparison result, until the number of calibrations is greater than N‑1, the calibrated optical power level is output; all light sources are turned on at the calibrated optical power level, the maximum voltage of all probes around each light source obtained within the second preset time length is compared with the second voltage threshold, and the signal quality of each channel is obtained according to the comparison result, and then whether to start a new round of optical power calibration is decided according to the signal quality of each channel.

Description

Technical Field

[0001] The present invention relates to a fast and automated optical power calibration method and device based on fNIRS equipment. Background Art

[0002] Functional near-infrared spectroscopy (fNIRS) is a noninvasive brain science technique that indirectly assesses brain function by measuring metabolic changes associated with neural activity (e.g., changes in oxygenated and deoxygenated hemoglobin in blood vessels). It offers excellent temporal and spatial resolution, flexibility, and portability, making it suitable for a wide range of subjects. Therefore, it has become a key technique for both basic brain research and clinical brain function assessment. Each signal channel in an fNIRS device consists of a transmitting and receiving photodee. Light emitted by the light source passes through the scalp, skull, meninges, cerebrospinal fluid, and gray matter, where it is scattered and absorbed before being received by the probe. The signal quality can be affected by factors such as the optical power of the transmitting photodee, the contact between the transmitting and receiving photodee and the subject's scalp, and the hair volume, scalp oiliness, and skull thickness at the locations of the transmitting and receiving photodeee.

[0003] Attachment Figure 1 This is a diagram of the layout of a near-infrared hat. S represents the light source, which emits two wavelengths of light: 690nm and 830nm. D represents the detector, which receives the light from the corresponding light sources. If the light intensity is insufficient, light will be scattered and absorbed, preventing it from being received by the detector. Therefore, the intensity of each light source must be sufficient. The device also uses an APD (Avalanche Photodiode) to convert the received light into a voltage. The stronger the received light, the higher the voltage. Due to hardware limitations, the APD can only withstand a limited voltage. When the detector receives light from different light sources, the APD converts the light into electricity. If the voltage exceeds a threshold, saturation will occur. To ensure a high signal-to-noise ratio for the received signal and to meet the varying light intensity requirements at different locations, the light intensity of each light source must be appropriately adjusted based on the location of each channel. Excessive light intensity can also cause saturation of the light received by the detector.

[0004] The light intensity is adjusted by the light power level, which is 0-2 N -1 of 2 NThe traditional method is to try different levels in sequence to ensure that the light is strong enough without saturation. However, this method not only consumes a lot of computation but also increases the calculation time (usually taking 30-60 seconds or even longer), which is not suitable for practical application scenarios. In addition, when the user adjusts the position of the optode, it is impossible to automatically calibrate it in real time based on the latest signal conditions, and a new round of calibration must be started again, which is time-consuming and labor-intensive. Summary of the Invention

[0005] To address the long optical power level calibration time issue, the present invention provides a fast, automated optical power calibration method based on fNIRS equipment. Through half-iteration, the optical power level of each light source at different wavelengths is rapidly determined, significantly reducing the number of adjustments, greatly improving computational efficiency, and enabling real-time computational updates.

[0006] According to one aspect of the present invention, a method for rapid automated optical power calibration based on an fNIRS device is provided, comprising:

[0007] Determine the initial optical power level to be 2 N-1 -1, where N represents the power corresponding to the total optical power level of the light source;

[0008] Based on the initial optical power level, 2 n Iterative calibration of optical power level is performed at intervals, where n is an integer and less than N-1;

[0009] During the iterative calibration process, when the number of calibrations is less than or equal to N-1, the maximum voltage of all probes around each light source obtained within the first preset time period is compared with the first voltage threshold, and the optical power level is adjusted according to the comparison result. When the number of calibrations is greater than N-1, the calibrated optical power level is output;

[0010] Turn on all light sources at the calibrated optical power level, compare the maximum voltage of all probes around each light source obtained within the second preset time period with the second voltage threshold, and obtain the signal quality of each channel based on the comparison result, and then decide whether to start a new round of optical power calibration based on the signal quality of each channel.

[0011] As a further technical solution, the method further includes:

[0012] The total optical power level of the light source is obtained, and the optical power level at a position where the total optical power level is half is used as the initial optical power level.

[0013] As a further technical solution, the method further includes:

[0014] The optical power levels of the two wavelengths of each light source are adjusted separately.

[0015] As a further technical solution, the method further includes:

[0016] Setting the initial optical power level of the first wavelength of the light source and turning off all light sources emitting light of the first wavelength;

[0017] Set the initial optical power level of the second wavelength of the light source and turn off all light sources emitting light of the second wavelength;

[0018] Turn on all light sources emitting light of the first wavelength, and based on the set initial optical power level of the first wavelength, n Iteratively calibrating the optical power level for the interval until a final optical power level corresponding to the first wavelength is obtained;

[0019] All light sources emitting light of the first wavelength are turned off, and all light sources emitting light of the second wavelength are turned on. Based on the set initial optical power level of the second wavelength, the power level is set to 2. n The optical power level is iteratively calibrated for the interval until a final optical power level corresponding to the second wavelength is obtained.

[0020] As a further technical solution, adjusting the optical power level according to the comparison result also includes:

[0021] When the maximum voltage of all probes around each light source obtained within the first preset time is greater than or equal to the first voltage threshold, the voltage is lowered by 2. n Interval, n is the power of the previous iterative calibration process minus one;

[0022] When the maximum voltage of all probes around each light source obtained within the first preset time is less than the first voltage threshold, increase by 2 n Interval, n is the power of the previous iterative calibration process minus one.

[0023] As a further technical solution, the calibrated optical power level is:

[0024]

[0025] Here, ± indicates whether to add or subtract based on the comparison result between the maximum voltage corresponding to the current optical power level and the first voltage threshold.

[0026] As a further technical solution, the maximum voltage of all probes around each light source obtained within the second preset time period is compared with the second voltage threshold, further comprising:

[0027] When the maximum voltage of all probes around each light source obtained within the second preset time period is greater than or equal to the second voltage threshold, the light source is considered to be saturated, and a new round of optical power calibration is started.

[0028] As a further technical solution, obtaining the signal quality of each channel according to the comparison result also includes:

[0029] When the maximum voltage of all probes around each light source obtained within the second preset time period is less than the second voltage threshold, compare the original light intensity of the current optical power level within the set time period with the light intensity threshold, and start a new round of optical power calibration when the original light intensity is less than or equal to the light intensity threshold.

[0030] According to one aspect of the present invention, a rapid automated optical power calibration device based on an fNIRS device is provided, comprising:

[0031] The first main module is used to determine the initial optical power level is 2 N-1 -1, where N represents the power corresponding to the total optical power level of the light source;

[0032] The second main module is used to adjust the initial optical power level to 2 n Iterative calibration of optical power level is performed at intervals, where n is an integer and less than N-1;

[0033] The third main module is used to compare the maximum voltage of all probes around each light source obtained within the first preset time period with the first voltage threshold when the number of calibrations is less than or equal to N-1 during the iterative calibration process, and adjust the optical power level according to the comparison result until the number of calibrations is greater than N-1, then output the calibrated optical power level;

[0034] The fourth main module is used to turn on all light sources at the calibrated optical power level, compare the maximum voltage of all probes around each light source obtained within the second preset time period with the second voltage threshold, and obtain the signal quality of each channel based on the comparison result, and then decide whether to start a new round of optical power calibration based on the signal quality of each channel.

[0035] According to one aspect of the present invention, a fiber optic cap is provided, which is equipped with the aforementioned fast automated optical power calibration device based on fNIRS equipment.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. This paper proposes a rapid and automated optical power calibration method based on fNIRS equipment. By using a semi-iterative algorithm to adjust the optical power level of each light source, it can ensure that the optical power is sufficiently high while the voltage received by each probe does not exceed the threshold, thus solving the problem of long optical power level calibration time.

[0038] 2. Taking the total optical power level of 512 as an example, the method of the present invention can reduce the traditional 512 adjustments to 9 times. The traditional calibration time is 30-60 seconds (or even longer). Now the calibration time only takes about 5 seconds, which improves calibration efficiency.

[0039] 3. During the traditional calibration process, if the calibration environment changes due to shaking of the photoelectrode or poor contact, recalibration is required to see the signal situation; however, the method of the present invention can calibrate in real time according to the current environment, and will provide real-time feedback on the latest situation when the environment changes, so that users can make quick adjustments. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Schematic diagram of a fiber optic cap in the prior art.

[0041] Figure 2 A schematic diagram of a flow chart of a rapid and automated optical power calibration method based on an fNIRS device provided in an embodiment of the present invention.

[0042] Figure 3 A schematic diagram of fast automatic optical power calibration with a total optical power level of 512 provided in an embodiment of the present invention.

[0043] Figure 4 A schematic diagram of a fast and automated optical power calibration device based on an fNIRS device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The following will clearly and completely describe the technical solutions of various embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0045] In the description of the present invention, “first” and “second” are only used for illustrative purposes and are not intended to limit the order unless otherwise clearly and specifically defined.

[0046] See also Figure 2 The embodiment of the present invention provides a fast and automated optical power calibration method based on fNIRS equipment. First, the initial optical power level is determined to be 2 N-1 -1, where N represents the power corresponding to the total optical power level of the light source; then, based on the initial optical power level, 2 nThe optical power level is iteratively calibrated at intervals, where n is an integer and is less than N-1. Subsequently, during the iterative calibration process, when the number of calibrations is less than or equal to N-1, the maximum voltage of all probes around each light source obtained within a first preset time period is compared with a first voltage threshold, and the optical power level is adjusted according to the comparison result until the number of calibrations is greater than N-1, and the calibrated optical power level is output. Finally, all light sources are turned on at the calibrated optical power level, the maximum voltage of all probes around each light source obtained within a second preset time period is compared with a second voltage threshold, and the signal quality of each channel is obtained based on the comparison result, and then a decision is made whether to start a new round of optical power calibration based on the signal quality of each channel.

[0047] This embodiment of the present invention uses a semi-iterative approach to rapidly determine the optical power levels of each light source at different wavelengths, significantly reducing the number of adjustments and improving computational efficiency. Furthermore, this embodiment uses semi-iterative analysis to adjust and update optical power levels in real time, promptly, accurately, and efficiently analyzing the appropriate optical power level for each light source in the current state, thereby improving device stability.

[0048] See also Figure 3 Taking the optical power level of 0-511, a total of 512 levels, as an example, the automatic calibration method of the present invention is used to adjust the optical power level of each light source wavelength of 690nm and 830nm, including the following steps:

[0049] 1. Set all 830nm optical power levels to 255 and turn off all 830nm light sources.

[0050] 2. Set all 690nm optical power levels to 255 and turn off all 690nm light sources. Wait 200 milliseconds for the device to stabilize, then turn on all 690nm light sources.

[0051] 3. Wait for 100 milliseconds, read the APD voltage peaks of all detectors around each light source for 10 consecutive milliseconds and take the maximum value. Adjust the optical power level according to the voltage value. If the voltage value is greater than or equal to A volt (the hardware upper limit is A+0.2 volt, with a 0.2 volt upper limit redundancy reserved), adjust it down, otherwise adjust it up. For example, when the optical power level is 127, the APD measured peak voltage is 3 volts (greater than A), then adjust it down. The optical power level after the adjustment is 255-2 7 = 2 8 -1-2 7 =127, if the peak voltage measured by APD is 1.8V (less than A), then it is adjusted upwards, and the optical power level after adjustment is 127+2 6 =191, repeat the judgment until 2 is added or subtracted 0 Determine the final optical power level. The optical power level formula is as follows:

[0052]

[0053] ± indicates whether the voltage is plus or minus based on the current optical power level.

[0054] 4. Turn off all 690nm light sources and turn on all 830nm light sources.

[0055] 5. Wait for 100 milliseconds, read the APD voltage peaks of all probes around each light source for 10 consecutive milliseconds and take the maximum value. Adjust the optical power level according to the voltage value. If the voltage value is greater than or equal to A volt, adjust it down; otherwise, adjust it up, as in step 3.

[0056] 6. Turn on all 690nm light sources. At this time, all 690nm and 830nm light sources are fully turned on.

[0057] 7. Wait 100 milliseconds, then read the peak APD voltages of all sensors around each light source for 10 milliseconds. Take the maximum value. If it is greater than or equal to B volts (B is the upper limit of the combined 690nm and 830nm wavelengths, B = A + 0.2 + A + 0.2 = 2A + 0.4), the light source is saturated. If it is less than B volts, further assess the signal quality. If the raw light intensity value exceeds threshold C (the raw light intensity threshold for a good signal) for two consecutive seconds, the channel color turns green, indicating a good signal. Otherwise, the channel color turns red, indicating poor signal quality.

[0058] 8. Repeat steps 1-7 above to adjust the optical power level and judge the signal quality of any current channel, providing a reference guide for the operator to adjust the photodiode cap.

[0059] By utilizing the above embodiment, the traditional 512 optical power level adjustments can be reduced to 9 times, which greatly improves the calibration efficiency.

[0060] It should be noted that the time limits in the above solutions, such as waiting for 100 milliseconds, reading for 10 milliseconds, and waiting for 200 milliseconds, can be adjusted according to actual conditions and are not intended to limit the present invention.

[0061] In other embodiments, for example, taking the optical power level of 0-1023, a total of 1024 levels, the optical power level of each light source wavelength of 690nm and 830nm is adjusted using the automated calibration method of the present invention. The other steps are the same as the above embodiment. The optical power level formula is:

[0062]

[0063] It can be seen that by using the method of the present invention, the traditional 1024 optical power level adjustments can be reduced to 10 times, greatly improving the calibration efficiency.

[0064] The implementation basis of each embodiment of the present invention is achieved through programmed processing by a device with processor functionality. Therefore, in engineering practice, the technical solutions and functions of each embodiment of the present invention are encapsulated into various modules. Based on this reality, on the basis of the above-mentioned embodiments, an embodiment of the present invention provides a rapid automated optical power calibration device based on an fNIRS device. This device is used to perform a rapid automated optical power calibration method based on an fNIRS device according to the above-mentioned method embodiment.

[0065] See also Figure 4 The device includes: a first main module, which is used to determine the initial optical power level as 2 N-1 -1, where N represents the power corresponding to the total optical power level of the light source; the second main module is used to increase the total optical power level based on the initial optical power level by 2 n To perform iterative calibration of the optical power level at intervals, n is an integer and is less than N-1; the third main module is used for comparing the maximum voltage of all probes around each light source obtained within the first preset time period with the first voltage threshold when the number of calibrations is less than or equal to N-1 during the iterative calibration process, and adjusting the optical power level according to the comparison result until the number of calibrations is greater than N-1, outputting the calibrated optical power level; the fourth main module is used to turn on all light sources at the calibrated optical power level, compare the maximum voltage of all probes around each light source obtained within the second preset time period with the second voltage threshold, and obtain the signal quality of each channel according to the comparison result, and then decide whether to start a new round of optical power calibration according to the signal quality of each channel.

[0066] The embodiment of the present invention provides a fast and automated optical power calibration device based on fNIRS equipment, which solves the problem of long optical power level calibration time. Figure 4 Several modules of the system can quickly determine the optical power level of each light source at different wavelengths through half-iteration, which greatly reduces the number of adjustments, greatly improves the calculation efficiency, and updates the calculation in real time.

[0067] It should be noted that the device embodiments provided by the present invention are not only used to implement the methods in the above-mentioned method embodiments, but also used to implement the methods in other method embodiments provided by the present invention. The only difference is the setting of corresponding functional modules. The principles thereof are basically the same as those of the above-mentioned device embodiments provided by the present invention. As long as those skilled in the art refer to the specific technical solutions in other method embodiments on the basis of the above-mentioned device embodiments, obtain corresponding technical means and technical solutions composed of these technical means by combining technical features, and on the premise of ensuring the practicality of the technical solutions, improve the modules in the above-mentioned device embodiments to obtain corresponding device-type embodiments, which are used to implement the methods in other method-type embodiments. For example:

[0068] Based on the content of the above device embodiment, as a preferred embodiment, the embodiment of the present invention provides a fast automated optical power calibration device based on an fNIRS device, wherein the first main module is further configured to execute the following instructions:

[0069] The total optical power level of the light source is obtained, and the optical power level at a position where the total optical power level is half is used as the initial optical power level.

[0070] Based on the content of the above device embodiment, as a preferred embodiment, in an embodiment of the present invention, a fast automated optical power calibration device based on an fNIRS device is provided, wherein the second main module is further configured to execute the following instructions:

[0071] The optical power levels of the two wavelengths of each light source are adjusted separately.

[0072] Based on the content of the above device embodiment, as a preferred embodiment, in an embodiment of the present invention, a fast automated optical power calibration device based on an fNIRS device is provided, wherein the second main module is further configured to execute the following instructions:

[0073] Setting the initial optical power level of the first wavelength of the light source and turning off all light sources emitting light of the first wavelength;

[0074] Set the initial optical power level of the second wavelength of the light source and turn off all light sources emitting light of the second wavelength;

[0075] Turn on all light sources emitting light of the first wavelength, and based on the set initial optical power level of the first wavelength, n Iteratively calibrating the optical power level for the interval until a final optical power level corresponding to the first wavelength is obtained;

[0076] All light sources emitting light of the first wavelength are turned off, and all light sources emitting light of the second wavelength are turned on. Based on the set initial optical power level of the second wavelength, the power level is set to 2. n The optical power level is iteratively calibrated for the interval until a final optical power level corresponding to the second wavelength is obtained.

[0077] Based on the content of the above device embodiment, as a preferred embodiment, in an embodiment of the present invention, a fast automated optical power calibration device based on an fNIRS device is provided, wherein the third main module is further configured to execute the following instructions:

[0078] When the maximum voltage of all probes around each light source obtained within the first preset time is greater than or equal to the first voltage threshold, the voltage is lowered by 2. n Interval, n is the power of the previous iterative calibration process minus one;

[0079] When the maximum voltage of all probes around each light source obtained within the first preset time is less than the first voltage threshold, increase by 2 n Interval, n is the power of the previous iterative calibration process minus one.

[0080] Based on the content of the above device embodiment, as a preferred embodiment, the embodiment of the present invention provides a fast and automated optical power calibration device based on an fNIRS device, and the optical power level after calibration is:

[0081]

[0082] Here, ± indicates whether to add or subtract based on the comparison result between the maximum voltage corresponding to the current optical power level and the first voltage threshold.

[0083] Based on the content of the above device embodiment, as a preferred embodiment, in an embodiment of the present invention, a fast automated optical power calibration device based on an fNIRS device is provided, wherein the fourth main module is further configured to execute the following instructions:

[0084] When the maximum voltage of all probes around each light source obtained within the second preset time period is greater than or equal to the second voltage threshold, the light source is considered to be saturated, and a new round of optical power calibration is started.

[0085] Based on the content of the above device embodiment, as a preferred embodiment, in an embodiment of the present invention, a fast automated optical power calibration device based on an fNIRS device is provided, wherein the fourth main module is further configured to execute the following instructions:

[0086] When the maximum voltage of all probes around each light source obtained within the second preset time period is less than the second voltage threshold, compare the original light intensity of the current optical power level within the set time period with the light intensity threshold, and start a new round of optical power calibration when the original light intensity is less than or equal to the light intensity threshold.

[0087] Based on the same inventive concept as the above embodiment, an embodiment of the present invention further provides a fiber optic cap equipped with the aforementioned fast automated optical power calibration device based on fNIRS equipment.

[0088] In summary, the present invention proposes a semi-iterative algorithm to adjust the optical power level of each light source, which can ensure that the optical power is large enough while the voltage received by each probe does not exceed the threshold. This solves the problem of long optical power level calibration time, reducing the traditional 512 adjustments to 9 times. The traditional calibration time is 30-60 seconds or even longer per round, but now the calibration time only takes about 5 seconds, which improves the calibration efficiency. In addition, during the traditional calibration process, if the calibration environment changes due to shaking of the photoelectrode or poor contact, recalibration is required to see the signal. This algorithm is calibrated in real time according to the current environment, and will provide real-time feedback on the latest situation when the environment changes, so that users can make quick adjustments.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A rapid and automated optical power calibration method based on fNIRS equipment, characterized in that: include: Determine the initial optical power level to be 2 N-1 -1, where N represents the power corresponding to the total optical power level of the light source; Based on the initial optical power level, 2 n Iterative calibration of optical power level is performed at intervals, where n is an integer and less than N-1; During the iterative calibration process, when the number of calibrations is less than or equal to N-1, the maximum voltage of all probes around each light source obtained within the first preset time period is compared with the first voltage threshold, and the optical power level is adjusted according to the comparison result. When the number of calibrations is greater than N-1, the calibrated optical power level is output; Turn on all light sources at the calibrated optical power level, compare the maximum voltage of all probes around each light source obtained within the second preset time period with the second voltage threshold, and obtain the signal quality of each channel based on the comparison result, and then decide whether to start a new round of optical power calibration based on the signal quality of each channel.

2. A rapid automated optical power calibration method based on fNIRS equipment according to claim 1, characterized in that: The method further comprises: The total optical power level of the light source is obtained, and the optical power level at a position where the total optical power level is half is used as the initial optical power level.

3. The rapid automated optical power calibration method based on fNIRS equipment according to claim 1, characterized in that: The method further comprises: The optical power levels of the two wavelengths of each light source are adjusted separately.

4. A rapid automated optical power calibration method based on fNIRS equipment according to claim 3, characterized in that: The method further comprises: Setting the initial optical power level of the first wavelength of the light source and turning off all light sources emitting light of the first wavelength; Set the initial optical power level of the second wavelength of the light source and turn off all light sources emitting light of the second wavelength; Turn on all light sources emitting light of the first wavelength, and based on the set initial optical power level of the first wavelength, n Iteratively calibrating the optical power level for the interval until a final optical power level corresponding to the first wavelength is obtained; All light sources emitting light of the first wavelength are turned off, and all light sources emitting light of the second wavelength are turned on. Based on the set initial optical power level of the second wavelength, the power level is set to 2. n The optical power level is iteratively calibrated for the interval until a final optical power level corresponding to the second wavelength is obtained.

5. The method for rapid automated optical power calibration based on fNIRS equipment according to claim 1, characterized in that: Adjusting the optical power level based on the comparison results also includes: When the maximum voltage of all probes around each light source obtained within the first preset time is greater than or equal to the first voltage threshold, the voltage is lowered by 2. n Interval, n is the power of the previous iterative calibration process minus one; When the maximum voltage of all probes around each light source obtained within the first preset time is less than the first voltage threshold, increase by 2 n Interval, n is the power of the previous iterative calibration process minus one.

6. A rapid automated optical power calibration method based on fNIRS equipment according to claim 5, characterized in that: The optical power levels after calibration are: ， Here, ± indicates whether to add or subtract based on the comparison result between the maximum voltage corresponding to the current optical power level and the first voltage threshold.

7. The rapid automated optical power calibration method based on fNIRS equipment according to claim 1, characterized in that: Comparing the maximum voltage of all probes around each light source obtained within the second preset time period with a second voltage threshold, further comprising: When the maximum voltage of all probes around each light source obtained within the second preset time period is greater than or equal to the second voltage threshold, the light source is considered to be saturated, and a new round of optical power calibration is started.

8. A rapid automated optical power calibration method based on fNIRS equipment according to claim 7, characterized in that: The signal quality of each channel is obtained based on the comparison results, including: When the maximum voltage of all probes around each light source obtained within the second preset time period is less than the second voltage threshold, compare the original light intensity of the current optical power level within the set time period with the light intensity threshold, and start a new round of optical power calibration when the original light intensity is less than or equal to the light intensity threshold.

9. A rapid automated optical power calibration device based on fNIRS equipment, characterized in that: include: The first main module is used to determine the initial optical power level is 2 N-1 -1, where N represents the power corresponding to the total optical power level of the light source; The second main module is used to adjust the initial optical power level to 2 n Iterative calibration of optical power level is performed at intervals, where n is an integer and less than N-1; The third main module is used to compare the maximum voltage of all probes around each light source obtained within the first preset time period with the first voltage threshold when the number of calibrations is less than or equal to N-1 during the iterative calibration process, and adjust the optical power level according to the comparison result until the number of calibrations is greater than N-1, then output the calibrated optical power level; The fourth main module is used to turn on all light sources at the calibrated optical power level, compare the maximum voltage of all probes around each light source obtained within the second preset time period with the second voltage threshold, and obtain the signal quality of each channel based on the comparison result, and then decide whether to start a new round of optical power calibration based on the signal quality of each channel.

10. A fiber optic cap, characterized in that: The invention is provided with the rapid automated optical power calibration device based on fNIRS equipment as claimed in claim 9.

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