Light transmittance adjusting method and SPAD device array

Abstract

The invention discloses a light transmittance adjusting method and an SPAD device array. The light transmittance adjusting method comprises the steps that the counting rate of a device body is acquired; under the condition that the counting rate of the device body does not meet a preset condition, determining a first light transmittance required by the light intensity adjusting structure based on the counting rate; and driving the light intensity adjusting structure by using a driving signal corresponding to the first light transmittance. According to the SPAD device, the counting rate of the device body is collected, the light transmittance of the light intensity adjusting structure is adjusted under the condition that the counting rate of the device body does not meet the preset condition, and due to the fact that the light transmittance of the light intensity adjusting structure is changed, the range that the SPAD device can receive larger light intensity can be effectively improved in an imaging scene, and the imaging quality of the SPAD device is improved. And the imaging range of the SPAD device is expanded.

Description

Technical Field

[0001] The present application relates to the field of semiconductor device technology, and in particular to a transmittance adjustment method and a SPAD device array. Background Art

[0002] Single-photon avalanche diodes (SPADs) are capable of detecting single photons. After a photon triggers an avalanche, it takes some time for the device to recover and detect the next photon. This recovery time determines the maximum photon rate the device can detect, or its saturation photon rate.

[0003] However, when SPAD devices are used for imaging, if there is a strong light source in the imaging scene, the SPAD device will have a count rate saturation problem. The light intensity information that exceeds the device's saturation photon rate will not be recorded and imaged, resulting in a limited imaging dynamic range. Summary of the Invention

[0004] The main purpose of this application is to provide a transmittance adjustment method, which aims to solve the technical problem that the imaging dynamic range of the SPAD device is limited when there is a strong light source in the imaging scene.

[0005] To achieve the above-mentioned objectives, the present application provides a driving structure for use in a SPAD device array; the SPAD device array comprises: the driving structure and a plurality of SPAD devices; the SPAD device comprises: a device body and a light intensity modulation structure, the light intensity modulation structure being connected to the driving structure and being disposed on the light incident side of the device body;

[0006] The light transmittance adjustment method comprises:

[0007] Obtaining a count rate of the device body;

[0008] determining a first light transmittance required by the light intensity modulation structure based on the count rate when the count rate of the device body does not meet a preset condition;

[0009] The light intensity adjustment structure is driven by a driving signal corresponding to the first light transmittance.

[0010] Optionally, the first light transmittance is a light transmittance corresponding to adjusting the counting rate to be within a preset counting rate threshold range; and failure to meet the preset condition is that the counting rate is not within the preset counting rate threshold range;

[0011] The step of driving the light intensity adjustment structure using a driving signal corresponding to the first light transmittance includes:

[0012] detecting the number of driving signals set for driving the light intensity adjustment structure during the transmittance adjustment process;

[0013] When the number of the driving signals is two, the light intensity adjustment structure is driven by the driving signal corresponding to the first light transmittance.

[0014] Optionally, after detecting the number of driving signals set for driving the light intensity adjustment structure during the transmittance adjustment process, the method further includes:

[0015] When the number of the driving signals is greater than two, obtaining a plurality of driving signals required to adjust the transmittance of the light intensity adjustment structure to the first transmittance;

[0016] The light intensity adjustment structure is driven in sequence using the amplitudes of the multiple driving signals.

[0017] Optionally, when the count rate of the device body does not meet a preset condition, determining a first light transmittance required by the light intensity modulation structure based on the count rate, the method further includes:

[0018] Obtaining a photon counting resolution requirement of the device body, and setting a lower endpoint of the preset count rate threshold range according to the photon counting resolution requirement;

[0019] Obtaining a saturation count rate of the device body, and setting an upper endpoint of the preset count rate threshold range according to the saturation count rate;

[0020] The preset count rate threshold range is set according to the lower endpoint and the upper endpoint.

[0021] Optionally, obtaining the saturation count rate of the device body and setting the upper endpoint of the preset count rate threshold range according to the saturation count rate includes:

[0022] Obtaining a saturation count rate of the device body, and setting an initial upper endpoint of the preset count rate threshold range according to the saturation count rate; the initial upper endpoint being the upper endpoint of the preset count rate threshold range before imaging the device body;

[0023] detecting a count rate of each of the device bodies during imaging of each of the device bodies and a second light transmittance of the corresponding light intensity modulation structure;

[0024] determining a light intensity value input to each of the device bodies according to the count rate, the second transmittance, and a second mapping relationship; wherein the second mapping relationship is a mapping relationship between the count rate of the device body, the transmittance of the light intensity modulation structure, and the light intensity value received by the light intensity modulation structure;

[0025] Obtaining a light intensity change value of the device body according to the light intensity values ​​of each of the device bodies detected in at least two cycles;

[0026] According to the light intensity change value of each device body, the corresponding initial upper limit endpoint is adjusted to obtain the upper limit endpoint of each preset count rate threshold range.

[0027] Optionally, the preset condition is not satisfied when the count rate is not a preset count rate, and the first transmittance is the transmittance required for the light intensity adjustment structure to adjust the count rate to the preset count rate; the setting parameters of the preset count rate include: a saturation count rate of the device body;

[0028] When the count rate of the device body does not meet a preset condition, determining the first transmittance required by the light intensity modulation structure based on the count rate includes:

[0029] determining a threshold relationship between the count rate and the preset count rate when the count rate of the device body is not a preset count rate;

[0030] A first light transmittance required by the light intensity adjustment structure is determined according to the threshold relationship.

[0031] Optionally, before obtaining the count rate of the device body, the method further includes:

[0032] detecting a driving mode of the light intensity modulation structure;

[0033] When the driving mode is a global driving mode, the count rates of all device bodies in the SPAD device array are obtained; the global driving mode is a driving mode in which the light intensity adjustment structure in each of the SPAD devices is driven by the same driving signal;

[0034] Obtaining a threshold ratio of the count rates greater than a preset count rate among the count rates;

[0035] When the threshold ratio is greater than a first preset ratio, the light intensity adjustment structure is driven in sequence by using a plurality of driving signals with gradually decreasing amplitudes;

[0036] When the threshold ratio is less than a second preset ratio, the light intensity adjustment structure is sequentially driven by a plurality of driving signals with gradually increasing amplitudes; and the first preset ratio is greater than the second preset ratio.

[0037] Optionally, after detecting the driving mode of the light intensity adjustment structure, the method further includes:

[0038] When the driving mode is an independent driving mode, performing the step of obtaining the counting rate of the device body;

[0039] The independent driving mode is a driving mode in which the light intensity modulation structure in each of the SPAD devices is driven by a driving signal required by each of the light intensity modulation structures.

[0040] In addition, to achieve the above-mentioned purpose, the present application also provides a SPAD device array, including: a driving structure and a plurality of SPAD devices;

[0041] The SPAD device comprises: a device body and a light intensity modulation structure, wherein the light intensity modulation structure is connected to the driving structure and is arranged on the light incident side of the device body; the device bodies of the SPADs are isolated by an isolation structure;

[0042] The driving structure is used to execute the transmittance adjustment method.

[0043] Optionally, the light intensity modulation structure includes: a polarizer, a common electrode layer, a liquid crystal layer, a thin film transistor layer and an analyzer arranged from top to bottom;

[0044] The polarizer is arranged above the device body; the common electrode layer and the thin film transistor layer are connected to the driving structure.

[0045] One or more technical solutions proposed in this application have at least the following technical effects:

[0046] The present application discloses a method for adjusting light transmittance, including: obtaining the count rate of the device body; determining a first transmittance required by the light intensity modulation structure based on the count rate when the count rate of the device body does not meet a preset condition; and driving the light intensity modulation structure using a drive signal corresponding to the first transmittance. In the present application, the count rate of the device body is collected, and when the count rate of the device body does not meet the preset condition, the transmittance of the light intensity modulation structure is adjusted. Due to the change in the transmittance of the light intensity modulation structure, the SPAD device can be effectively increased in the imaging scene to receive a wider range of light intensities, thereby improving the imaging dynamic range of the SPAD device, while suppressing the count rate of the SPAD device under strong light, without the need to set up an additional sensor to detect light intensity, thereby reducing sensor power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following briefly introduces the drawings required for use in the embodiments or related technical descriptions. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0049] Figure 1 This is a schematic diagram of the first structure of the SPAD device in the SPAD device array proposed in this application;

[0050] Figure 2 This is a schematic diagram of the second structure of the SPAD device in the SPAD device array proposed in this application;

[0051] Figure 3 This is a flow chart of the first embodiment of the light transmittance adjustment method proposed in this application;

[0052] Figure 4 This is a flow chart of the second embodiment of the light transmittance adjustment method proposed in this application;

[0053] Figure 5 This is a graph showing changes in count rate and incident photon rate when the number of driving signals is two in the second embodiment of the transmittance adjustment method proposed in this application;

[0054] Figure 6 This is a graph showing changes in the count rate and incident photon rate when the number of driving signals is greater than two in the second embodiment of the transmittance adjustment method proposed in this application;

[0055] Figure 7 This is a flow chart of the third embodiment of the light transmittance adjustment method proposed in this application;

[0056] Figure 8 A graph showing the change in the upper limit endpoint of the preset count rate threshold range and the rate of change of the incident photon rate in the third embodiment of the transmittance adjustment method proposed in this application;

[0057] Figure 9 This is a schematic structural diagram of dynamically adjusting the upper limit endpoint of a preset count rate threshold range in the third embodiment of the transmittance adjustment method proposed in this application;

[0058] Figure 10 This is a flow chart of a fourth embodiment of the light transmittance adjustment method proposed in this application;

[0059] Figure 11This is a graph showing changes in count rate and incident photon rate in the fourth embodiment of the transmittance adjustment method proposed in this application;

[0060] Figure 12 This is a flow chart of a fifth embodiment of the light transmittance adjustment method proposed in this application;

[0061] Figure 13 This is a schematic structural diagram of a SPAD device array in a global driving mode in the fifth embodiment of the transmittance adjustment method proposed in this application;

[0062] Figure 14 This is a structural diagram of the SPAD device array under independent driving mode in the fifth embodiment of the transmittance adjustment method proposed in this application.

[0063] The realization of the objectives, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0064] It should be understood that the specific embodiments described herein are merely used to explain the technical solutions of the present application and are not intended to limit the present application.

[0065] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0066] In the field of imaging technology, SPAD devices can detect single photons. This is achieved by applying a reverse bias voltage exceeding the breakdown voltage to the SPAD device. When a photon is incident and generates an electron-hole pair in the diode, the electron-hole pair is accelerated by the reverse bias, triggering more electron-hole pairs, forming an avalanche effect and generating a detectable avalanche current, thereby enabling single photon detection.

[0067] The parameters of the SPAD device include the counting rate. When the external light intensity changes, the number of particles entering the SPAD device will also change. When the light intensity reaches a certain value, the counting rate of the SPAD device is saturated. At this time, stronger light intensity cannot complete normal imaging in the SPAD device, and the imaging range of the SPAD device is limited.

[0068] Although there are methods for imaging with higher light intensities in this field, such as reducing the light intensity input to the SPAD device by setting up devices such as apertures, light intensity attenuators, and optical crystals, in actual use, additional optical sensors are required to collect the light intensity and then adjust the light intensity based on the light intensity using devices such as apertures, light intensity attenuators, and optical crystals. This process requires the use of additional optical sensors, which significantly increases the overall power consumption and cost of the imaging process.

[0069] Therefore, in order to overcome the above-mentioned defects, the present application provides a transmittance adjustment method including: first obtaining the counting rate of the device body; when the counting rate of the device body does not meet the preset conditions, determining the first transmittance required by the light intensity adjustment structure based on the counting rate; and driving the light intensity adjustment structure using a driving signal corresponding to the first transmittance.

[0070] Since the count rate of the device body is collected in the present application, the transmittance of the light intensity modulation structure is adjusted when the count rate of the device body does not meet the preset conditions. Since the transmittance of the light intensity modulation structure changes, the SPAD device can effectively increase the light intensity range that can be received in the imaging scene, thereby improving the imaging range of the SPAD device.

[0071] Reference Figure 1 , Figure 1 This is a schematic diagram of the first structure of the SPAD device in the SPAD device array proposed in this application.

[0072] exist Figure 1 The SPAD device includes: a device body 10 and a light intensity modulation structure 20, wherein the light intensity modulation structure 20 is connected to the driving structure and is arranged on the light incident side of the device body 10; the device bodies of each SPAD in the SPAD device array are isolated by an isolation structure.

[0073] It should be understood that the device body 10 is a device within the SPAD device for receiving photons input from an external light source for detection, and the detected photons can be used for imaging. When the reverse bias voltage is too large, the detection of photons can be achieved through the avalanche effect within the device body 10. The light intensity modulation structure 20 is a structure for adjusting the intensity of light passing through the structure, and the intensity of light passing through the light intensity modulation structure 20 will change. The light intensity modulation structure 20 can be composed of devices with adjustable transmittance, such as optical crystals and liquid crystals. By setting different parameters of the light intensity modulation structure 20, the transmittance of the optical crystal can be changed, thereby adjusting the intensity of light passing through. The driving structure is a device for driving the light intensity modulation structure 20. When different driving parameters are used, the light intensity modulation structure 20 can exhibit different transmittances, thereby adjusting the light intensity. The driving structure is provided with structures such as logic devices and acquisition devices, which can collect relevant parameters of the SPAD device, and then use different driving parameters to drive the light intensity modulation structure 20 according to the different collected parameters. Considering that many SPAD devices are arranged in the SPAD device array, in order to avoid interference between the various SPAD devices, the device body 10 of the SPAD device can be isolated by an isolation structure.

[0074] In a specific implementation, the driving structure can obtain the counting rate of the device body of the SPAD device during the imaging process. When the counting rate does not meet the preset conditions, it indicates that there are photons of some light intensities that cannot be detected normally. At this time, the driving structure can adjust the driving parameters input into the light intensity modulation structure 20 to change the transmittance of the light intensity modulation structure 20, so that the light intensity received by the device body 10 is within the range that can detect photons normally.

[0075] Among them, the counting rate is the counting rate presented in the device body collected during the current imaging process. Within the range where the counting rate is not saturated, the counting rate changes with the change of light intensity. The preset condition is a counting rate condition preset before imaging. The preset condition can be a preset counting rate, and the transmittance of the light intensity modulation structure 20 is adjusted when the counting rate of the device body is greater than or less than the preset counting rate; or the preset condition can be a preset counting rate threshold range, and the transmittance of the light intensity modulation structure 20 is adjusted when the currently acquired counting rate is not within the preset counting rate threshold range. When the transmittance of the light intensity modulation structure 20 is adjusted as described above, the SPAD device can effectively detect photons with stronger light intensity under the saturated counting rate condition.

[0076] Furthermore, in the process of adjusting the transmittance of the light intensity adjustment structure 20, the optical adjustment structure 20 including liquid crystal can be used as an example for description. Figure 2 , Figure 2 This is a schematic diagram of the second structure of the SPAD device in the SPAD device array proposed in this application.

[0077] exist Figure 2 In the embodiment, the light intensity modulation structure 20 specifically includes: a polarizer 21, a common electrode layer 22, a liquid crystal layer 23, a thin film transistor layer 24 and an analyzer 25 arranged from top to bottom;

[0078] The analyzer 25 is disposed above the device body 10 ; the common electrode layer 22 and the thin film transistor layer 24 are connected to the driving structure.

[0079] It should be noted that the polarizer 21 is a device for adjusting the incident light into linearly polarized light, which is light that can be normally adjusted by the liquid crystal layer 23. The common electrode layer 22 and the thin film transistor layer 24 are structures for adjusting the voltage across the liquid crystal in the liquid crystal layer 23. When the common electrode layer 22 and the thin film transistor layer 24 present different voltages across the liquid crystal, the liquid crystal can be deflected at different angles, thereby adjusting the angle of the linearly polarized light. The common electrode layer 22 is used to provide a common voltage for each liquid crystal in the liquid crystal layer 23, and the thin film transistor layer 24 can provide a different driving voltage for each liquid crystal, thereby controlling the voltage value across the liquid crystal to change. A plurality of thin film transistors are provided in the thin film transistor layer 24, and each thin film transistor can adjust the voltage of the liquid crystal corresponding to a pixel. The analyzer 25 is a structure used to filter out light in the received linearly polarized light that has a certain angle with the plane where the analyzer 25 is located. When the polarization direction of the linear polarized light passing through the liquid crystal is parallel to the analyzer, the transmittance of the incident light is the largest. When the polarization direction of the linear polarized light passing through the liquid crystal is perpendicular to the analyzer, the transmittance of the incident light is the smallest.

[0080] In a specific implementation, when the driving structure determines that the counting rate threshold of the device body does not meet the preset conditions, the voltage value input to each thin film transistor in the thin film transistor layer 24 can be adjusted, and then the voltage value at both ends of each liquid crystal in the liquid crystal layer 23 can be adjusted to make the liquid crystal deflect at different angles. The linearly polarized light input to the liquid crystal layer 23 through the polarizer 21 and the common electrode layer 22 will change the angle of the light due to the angle of the liquid crystal deflection. Finally, part of the light in the linearly polarized light is filtered out by the polarizer 25, thereby adjusting the amount of light entering the SPAD device.

[0081] During the driving process of the liquid crystal layer 23, since the common electrode layer 22 provides a voltage with a constant voltage value, the gate of each thin film transistor in the thin film transistor layer 24 receives a scanning signal to turn on the thin film transistor; the input end of the thin film transistor can receive a data signal with a different voltage value, that is, a driving signal. The data signal can form different voltages at both ends of the liquid crystal layer 23 with the voltage provided by the common electrode layer 22, thereby controlling the rotation of the liquid crystal in the liquid crystal layer 23.

[0082] In the present application, through the setting of the above-mentioned structure, the driving structure can be used to obtain the counting rate of the device body. When the counting rate of the device body does not meet the preset conditions, the transmittance of the light intensity regulation structure 20 is adjusted. Since the transmittance of the light intensity regulation structure 20 changes, the device body 10 of the SPAD device can effectively improve the larger light intensity range that can be received in the imaging scene, thereby improving the imaging dynamic range of the SPAD device, and at the same time suppressing the counting rate of the SPAD device under strong light, and there is no need to set up an additional sensor to detect the light intensity, thereby reducing the power consumption of the sensor.

[0083] Based on the structure of the SPAD device in the above-mentioned SPAD device array, the embodiment of the present application provides a method for adjusting the transmittance, referring to Figure 3 , Figure 3 This is a flow chart of the first embodiment of the transmittance adjustment method proposed in this application.

[0084] In a first embodiment, the light transmittance adjustment method includes:

[0085] Step S10: obtaining the counting rate of the device body.

[0086] It should be noted that the device body is the component within the SPAD device that receives and detects photons from an external light source. The detected photons can be used for imaging. The count rate is the count rate observed within the device body during the current imaging process. This count rate varies with light intensity within the non-saturated range.

[0087] During the specific detection process, the avalanche current generated by the avalanche effect in the device body can be detected, and the counting rate corresponding to the device body under the current imaging conditions can be determined according to the specific value of the avalanche current. Of course, the counting rate of the device body can also be directly collected by other means, which are not specifically limited here.

[0088] Step S20: When the count rate of the device body does not meet a preset condition, determining a first light transmittance required by the light intensity modulation structure based on the count rate.

[0089] It should be understood that the preset condition is a count rate condition that is preset before presentation. The preset condition can be a preset count rate, and the transmittance of the light intensity modulation structure 20 is adjusted when the count rate of the device body is greater than or less than the preset count rate; or the preset condition can be a preset count rate threshold range, and the transmittance of the light intensity modulation structure 20 is adjusted when the currently acquired count rate is not within the preset count rate threshold range. The first transmittance is the transmittance corresponding to the count rate meeting the preset condition. For example, when the count rate of the device body is very high, the current transmittance of the light intensity modulation structure can be reduced to reduce the amount of light entering the device body, thereby reducing the count rate of the device body. At this time, the first transmittance is less than the current transmittance of the light intensity modulation structure. When the count rate of the device body is very low, the current transmittance of the light intensity structure can be increased to increase the amount of light entering the device body, thereby improving the count rate of the device body. At this time, the first transmittance is greater than the current transmittance of the light intensity structure.

[0090] In the specific determination process, it can be determined whether the first transmittance should be greater than or less than the current transmittance of the light intensity modulation structure based on the directional difference between the counting rate that meets the preset conditions and the current counting rate of the device body; then, the difference between the current transmittance of the light intensity modulation structure and the first transmittance is determined based on the counting rate difference between the counting rate that meets the preset conditions and the current counting rate of the device body, and then the first transmittance required by the light intensity modulation structure is determined when the counting rate meets the preset conditions.

[0091] Step S30: driving the light intensity adjustment structure using a driving signal corresponding to the first light transmittance.

[0092] It should be understood that once the desired first transmittance of the light intensity modulation structure is determined, the transmittance of the light intensity modulation structure also needs to be adjusted from the currently displayed transmittance to the first transmittance. The drive signal is a signal that drives changes in transmittance-related structures within the light intensity modulation structure. For example, in the case of a liquid crystal layer, the drive signal is a signal used to drive changes in the deflection angle of the liquid crystal. Different drive signals input to the light intensity modulation structure adjust the parameters within the optical adjustment structure to varying degrees, thereby resulting in different transmittances displayed by the light intensity modulation structure.

[0093] In a specific implementation, when the first transmittance required by the light intensity structure is determined, a corresponding driving signal can be generated in the driving structure based on the first transmittance, and then the driving signal is input to the light intensity adjustment structure, so that the transmittance presented by the light intensity adjustment structure is the first transmittance, and the counting rate of the device body meets the preset conditions.

[0094] In this embodiment, the counting rate of the device body is collected. When the counting rate of the device body does not meet the preset conditions, the transmittance of the light intensity modulation structure is adjusted. Since the transmittance of the light intensity modulation structure changes, the SPAD device can effectively increase the light intensity range that can be received in the imaging scene, thereby improving the imaging range of the SPAD device.

[0095] Based on the above first embodiment, a second embodiment of the light transmittance adjustment method of the present application is proposed. Figure 4 , Figure 4 This is a flow chart of the second embodiment of the transmittance adjustment method proposed in this application.

[0096] It should be understood that in this embodiment, the preset condition is a predetermined count rate threshold range. If the preset condition is satisfied, the count rate is considered to be within the threshold range, and if the preset condition is not satisfied, the count rate is considered to be outside the preset count rate threshold range. The first transmittance is the transmittance corresponding to the case where the count rate is within the preset count rate threshold range.

[0097] In this embodiment, step S30 includes:

[0098] Step S301: detecting the number of driving signals set for driving the light intensity adjustment structure during the transmittance adjustment process.

[0099] It should be understood that when adjusting the transmittance of the light intensity modulation structure during imaging using a SPAD device array, the preset count rate threshold range is a predefined range of values ​​used to control the count rate variation of the device body. If the count rate is greater than the upper limit of the preset count rate threshold range, this indicates that the current count rate of the device body is high, likely approaching the saturation count rate, making proper imaging impossible and requiring the transmittance of the light intensity modulation structure to be reduced. Conversely, if the count rate is less than the lower limit of the preset count rate threshold range, this indicates that the current count rate of the device body is too low, and the transmittance of the light intensity modulation structure can be appropriately increased.

[0100] It is understandable that, because the preset count rate threshold is a range value, if the drive signal is a drive signal with a fixed voltage value during the process of adjusting the transmittance of the light intensity modulator structure, the transmittance of the light intensity modulator structure cannot be adjusted. Therefore, when setting the drive signal, it is necessary to set at least two drive signals with different voltage values, each drive signal corresponding to a transmittance. The transmittance adjustment process for the light intensity modulator structure is also different when the number of drive signals is different. For example, when setting two drive signals with different voltage values, the current transmittance of the light intensity modulator structure corresponds to one drive signal. If the count rate is not within the preset count rate threshold range, the other drive signal is the drive signal corresponding to the first transmittance. In this case, the light intensity modulator structure can be directly adjusted using the drive signal with the other voltage value. If there are more than two drive signals, adjusting the current transmittance of the light intensity modulator structure to the first transmittance may involve multiple drive signals driving in stages, or skipping stages, etc.

[0101] Step S302 : when the number of the driving signals is two, driving the light intensity adjustment structure using the driving signal corresponding to the first light transmittance.

[0102] It should be understood that when the number of driving signals is two, the light intensity adjustment structure corresponds to two transmittances, wherein the driving signal of the first voltage value corresponds to the larger transmittance a1, and the driving signal of the second voltage value corresponds to the smaller transmittance a2, wherein the first transmittance a1 is greater than the second transmittance a2; the upper limit endpoint of the preset counting rate threshold range is C1, and the lower limit endpoint is C2.

[0103] During imaging using a SPAD device, the transmittance of the light intensity modulation structure can be a first transmittance a1, and then the count rate of the device body is detected in real time. When the count rate is greater than the upper limit endpoint C1 of a preset count rate threshold range, the smaller transmittance a2 is used as the first transmittance, and then the light intensity modulation structure is driven by a driving signal of a second voltage value corresponding to the smaller transmittance a2, thereby reducing the current transmittance of the light intensity modulation structure to the smaller transmittance a2, and the corresponding count rate of the device body gradually decreases to less than the upper limit endpoint C1 of the preset count rate threshold range. During imaging using the first transmittance, the count rate of the device body is continuously detected. When the count rate decreases to less than the lower limit endpoint C2 of the preset count rate threshold range, the larger transmittance a1 is required to be used as the first transmittance, and then the light intensity modulation structure is driven by a driving signal of a first voltage value corresponding to the larger transmittance a1, thereby increasing the current transmittance of the light intensity modulation structure to the larger transmittance a1, and the corresponding count rate of the device body gradually increases to greater than the lower limit endpoint C2 of the preset count rate threshold range.

[0104] In this process, by adjusting the two transmittances corresponding to the two driving signals, the range of incident light intensity that the SPAD device can receive, i.e., the range of incident photon rate, can be effectively improved. The actual received light intensity, i.e., the incident photon rate, is: I = C / a / PDE; (1);

[0105] Where PDE is the photon detection efficiency of the SPAD device, which physically means the probability of a single photon being detected by the SPAD device when it is incident, C is the count rate, a is the transmittance of the light intensity modulation structure, and I is the incident photon rate, i.e., the light intensity. Figure 5 , I0 is the photon incidence rate that the device body can receive when the transmittance is a1 and the count rate is the upper limit endpoint C1 of the preset count rate threshold range, or is the photon incidence rate that the device body can receive when the transmittance is a2 and the count rate is the lower limit endpoint C2 of the preset count rate threshold range; I S1 I is the photon incidence rate that the device can receive when the transmittance is a1 and the count rate is the saturation count rate, that is, the maximum light intensity that can be received. S2 The photon incidence rate that the device body can receive when the transmittance is a2 and the counting rate is the saturation counting rate, that is, the maximum light intensity that can be received. Figure 5 The incident photon rate can be adjusted from zero to I S2 , where the maximum incident photon rate that the SPAD device can receive is given by I S1 Upgrade to I S2 , effectively improving the range of light intensity that the SPAD device can receive.

[0106] After step S301, the following steps are further included:

[0107] Step S303: when the number of the driving signals is greater than two, obtaining a plurality of driving signals required to adjust the transmittance of the light intensity adjustment structure to the first transmittance.

[0108] It should be understood that when the number of driving signals is set to be greater than two, in the process of adjusting the current transmittance of the light intensity adjustment structure to the first transmittance, taking into account the change in the voltage value of the driving signal, multiple driving signals may be required to drive the light intensity adjustment structure until the driving signal with the voltage value corresponding to the first transmittance drives the light intensity adjustment structure. For example, when n driving signals are set, n is greater than 2, and the transmittances corresponding to the driving signals include a1, a2, a3, ... an; if the transmittance of the light intensity structure needs to be adjusted from a1 to a3, the transmittance needs to be adjusted from a1 to a2 and then from a2 to a3. The corresponding driving signal required to adjust the transmittance a1 to a3 is to first adjust the driving signal corresponding to the transmittance a1 to the driving signal corresponding to the transmittance a2, and then adjust the driving signal corresponding to the transmittance a2 to the driving signal corresponding to the transmittance a3, involving the conversion of three driving signals. Therefore, when the number of driving signals is greater than two, it is necessary to first determine the multiple driving signals required for the transmittance of the light intensity adjustment structure to be adjusted to the first transmittance.

[0109] In the specific determination process, the count rate that needs to be adjusted can be determined based on the current count rate of the device body and the count rate within the preset count rate threshold range, and then the first transmittance required by the light intensity adjustment structure can be determined based on the relationship between the count rate and the transmittance, and finally the driving signal set between the current transmittance and the first transmittance is extracted.

[0110] Step S304: driving the light intensity adjustment structure in sequence using the amplitudes of the plurality of driving signals.

[0111] It is understandable that the amplitudes of the multiple drive signals increase or decrease sequentially, for example, the amplitude of the first drive signal is 1V, the amplitude of the second drive signal is 0.9V, and the amplitude of the third drive signal is 0.8V. When multiple drive signals are determined, the light intensity modulation structure is driven sequentially according to the drive signals with successively increasing or decreasing amplitudes until the drive signal corresponding to the first transmittance drives the light intensity modulation structure, or until the transmittance exhibited by the light intensity modulation structure is the first transmittance.

[0112] During the actual imaging process, the initial value of the transmittance of the light intensity modulation structure is the maximum value a1, and then the count rate of the device body is detected in real time. Whenever the count rate exceeds C1, the transmittance of the light intensity modulation structure is gradually reduced by inputting driving signals of different voltage values ​​through voltage regulation, from the current transmittance to the first transmittance; whenever the count rate is lower than C2, the transmittance of the light intensity modulation structure is gradually increased by inputting driving signals of different voltage values ​​through voltage regulation, from the current transmittance to the first transmittance. The actual light intensity is calculated by the actual SPAD count rate C and the actual liquid crystal transmittance a, that is, calculated by the above formula (1). The change of SPAD count rate with incident photon rate (light intensity) is referred to Figure 6 , in the process of light transmittance adjustment. When the light transmittance is not adjusted, the maximum detectable photon rate is I s1 =C s / a1 / PDE. By sequentially driving the transmittance adjustment scheme with multiple driving signals, the maximum photon detection rate can be increased to I sn =C s / a n / PDE, dynamic range increased by a1 / a n times.

[0113] Based on the first and second embodiments of the above-mentioned light transmittance adjustment method, a third embodiment of the light transmittance adjustment method of the present application is proposed. Figure 7 , Figure 7 This is a flow chart of the third embodiment of the transmittance adjustment method proposed in this application.

[0114] In this embodiment, before step S20, the following steps are further included:

[0115] Step S201: obtaining the photon counting resolution requirement of the device body, and setting the lower endpoint of the preset counting rate threshold range according to the photon counting resolution requirement.

[0116] It should be understood that before comparing the count rate with the endpoint value in the preset count rate threshold range to determine whether the count rate is within the preset count rate threshold range, it is also necessary to set the preset count rate threshold range according to the actual imaging requirements during the imaging process, so that during the imaging process, the count rate can be compared with the endpoint value of the preset count rate threshold range to determine whether the count rate meets the preset conditions.

[0117] It can be understood that the upper and lower endpoints of the counting rate threshold range affect the imaging effect as follows: the lower endpoint determines the photon counting resolution of imaging under weak light conditions. A lower lower endpoint will cause the transmittance of the light intensity modulation structure to remain at a lower state under weak light conditions, and the photon resolution will be reduced. The upper endpoint determines the number of times the transmittance of the light intensity modulation structure is adjusted. A higher upper endpoint will allow the transmittance of the light intensity modulation structure corresponding to each driving signal to cope with a wider range of light intensities, reducing the number of times the light intensity modulation structure is adjusted when the light intensity changes, and improving the imaging effect, but a higher upper endpoint will increase pixel power consumption.

[0118] It should be noted that the photon counting resolution requirement is the resolution requirement set by the SPAD device during the imaging process. The photon counting resolution requirement is mainly used to reflect the photon sensitivity of imaging under low light. For example, when the photon counting resolution is 100 units, that is, an average of 100 photons generate one count. At this time, 10 photons or 30 photons in a period of time may be indistinguishable, and no counts can be generated. However, if the photon resolution is 10, 10 photons and 30 photons will be counted as 1 and 3 respectively, which can effectively distinguish the number of photons received under low light. The lower endpoint of the preset count rate threshold range can be set according to the photon counting resolution requirement to meet the resolution requirement of the SPAD device to present the picture. The photon counting resolution requirement needs to be set according to the specific resolution requirement of the specific picture to be presented.

[0119] In a specific implementation, the specific resolution requirement of the SPAD device that currently needs to present the image can be obtained first, and then the sub-counting resolution requirement required by the device body can be determined based on the resolution requirement. The minimum amount of light input required by the device body to meet the sub-counting resolution requirement can be determined based on the sub-counting resolution requirement. Then, the lower end point of the preset count rate threshold range corresponding to the minimum amount of light input can be set based on the relationship between the amount of light input and the count rate.

[0120] Step S202: Acquire the saturation count rate of the device body, and set the upper endpoint of the preset count rate threshold range according to the saturation count rate.

[0121] It should be understood that the upper endpoint of the preset count rate threshold range generally needs to be set lower than the saturation count rate of the device itself. While retaining a certain adjustable space, the upper endpoint of the preset count rate threshold range is set based on the saturation count rate. The saturation count rate of the device itself is related to the specific photon detection capability of the SPAD device, and different SPAD devices have different photon detection capabilities. When the SPAD device is determined, the saturation count rate of the device can be directly determined, and then the upper endpoint of the count rate threshold range can be set based on the saturation count rate, where the count rate corresponding to the upper endpoint is lower than the saturation count rate.

[0122] Step S203: setting the preset count rate threshold range according to the lower endpoint and the upper endpoint.

[0123] It is understandable that, when both the upper endpoint and the lower endpoint of the preset count rate threshold range are determined, the preset count rate threshold range can be set directly according to the lower endpoint and the upper endpoint.

[0124] Furthermore, in this embodiment, step S202 further includes:

[0125] Step S2021: Acquire the saturation count rate of the device body, and set the initial upper limit endpoint of the preset count rate threshold range according to the saturation count rate; the initial upper limit endpoint is the upper limit endpoint of the preset count rate threshold range before imaging the device body.

[0126] It should be understood that during imaging using a SPAD device, the light intensity at different locations on the array may vary. To ensure image quality, a higher upper endpoint is typically set. This higher upper endpoint allows the light intensity modulation structure's transmittance to allow the device body to receive a wider range of light intensities, reducing the number of liquid crystal adjustments required when light intensity varies, and improving imaging quality. However, a higher upper endpoint increases pixel power consumption. Therefore, a higher upper endpoint can be set in areas with large light intensity variations to ensure good imaging quality, while a lower upper endpoint can be set in areas with smaller light intensity variations to reduce the overall power consumption of the SPAD device array.

[0127] It should be noted that the change in illumination intensity refers to the change in light intensity received by the SPAD device array during the imaging process. During the imaging process, an upper limit endpoint needs to be pre-set for SPAD device imaging. The initial upper limit endpoint is the upper limit endpoint of the preset count rate threshold range before imaging of the device body. This initial upper limit endpoint can be set based on the saturation count rate of the SPAD device.

[0128] Step S2022: detecting the count rate of each device body and the corresponding second transmittance of the light intensity modulation structure during the imaging process of each device body.

[0129] It should be understood that during the imaging process, it is necessary to determine the light intensity value input to the device body. In the actual determination process, a light sensor is not set up to detect the light intensity value due to cost factors. In this embodiment, the light intensity value received by the device body can be determined based on the counting rate and transmittance.

[0130] It should be noted that the count rate is the count rate reflected by the device body during the imaging process, and the second transmittance is the transmittance presented by the light intensity modulation structure during the imaging process.

[0131] Step S2023: determining a light intensity value input to each of the device bodies according to the counting rate, the second transmittance, and a second mapping relationship;

[0132] It should be noted that the second mapping relationship is a mapping relationship between the count rate of the device body, the transmittance of the light intensity modulation structure, and the light intensity value received by the light intensity modulation structure. In the actual imaging process, when the light intensity remains unchanged, the transmittance and the count rate are also positively correlated; when the count rate remains unchanged, the light intensity received by the device body is negatively correlated with the transmittance; when the transmittance of the light intensity modulation structure remains unchanged, the light intensity received by the device body is positively correlated with the count rate of the device body. The second mapping relationship between the transmittance, the count rate, and the light intensity is: I = C / a / PDE. It can be seen that when the count rate and the second transmittance are collected during the imaging process, the light intensity value at the corresponding moment can be directly determined through the second mapping relationship based on the count rate and the second transmittance.

[0133] Step S2024: obtaining a light intensity change value of the device body according to the light intensity values ​​of each device body detected in at least two cycles.

[0134] It is understandable that, referring to Figure 8 The adjustment of the upper limit endpoint needs to be based on the change in light intensity and the light intensity change value. Therefore, in this embodiment, it is also necessary to detect the light intensity value of each device body within at least two cycles, and then determine the light intensity change value corresponding to the device body of each SPAD device in the SPAD device array based on the calculated light intensity values ​​within multiple cycles.

[0135] Step S2025: According to the light intensity change value of each device body, the corresponding initial upper limit endpoint is adjusted to obtain the upper limit endpoint of each preset count rate threshold range.

[0136] In the specific setting process, refer to Figure 9 The upper limit of the preset count rate threshold range can be dynamically adjusted based on the light intensity variation of the device body. In areas with large light intensity variations, the upper limit of the preset count rate threshold range corresponding to the device body can be increased to ensure the imaging effect; while in areas with small light intensity variations, the upper limit of the preset count rate threshold range corresponding to the device body can be lowered to reduce the overall power consumption of the SPAD device array.

[0137] In each cycle of the imaging process, the upper limit endpoint of the preset count rate threshold range can be dynamically adjusted according to the light intensity change value between the previous cycle and the current cycle, thereby reducing the overall power consumption of the SPAD device while ensuring imaging quality.

[0138] The fourth embodiment of the light transmittance adjustment method of the present application is proposed based on any one of the first to third embodiments of the light transmittance adjustment method. Figure 10 , Figure 10 This is a flow chart of the fourth embodiment of the transmittance adjustment method proposed in this application.

[0139] In this embodiment, the preset condition is not satisfied when the count rate is not a preset count rate, and the first transmittance is the transmittance required for the light intensity adjustment structure to adjust the count rate to the preset count rate; the setting parameters of the preset count rate include: a saturation count rate of the device body;

[0140] The step S20 includes:

[0141] Step S21: when the count rate of the device body is not a preset count rate, determining a threshold relationship between the count rate and the preset count rate.

[0142] It should be understood that in the process of adjusting the transmittance of the light intensity modulation structure according to the counting rate, a preset counting rate threshold can also be set. During the imaging process, while maintaining the counting rate at the preset transmittance, the transmittance of the light intensity modulation structure can be adjusted in real time according to the change in light intensity, thereby further increasing the range of light intensity that the device body can receive.

[0143] It should be noted that at the beginning of the imaging process, the transmittance of the light intensity modulation structure is a fixed value, and then the transmittance of the light intensity modulation structure can be adjusted only when the count rate changes with the light intensity. In the case where the count rate changes according to the light intensity, it is necessary to determine the degree of adjustment of the transmittance. Since the transmittance is positively correlated with the count rate, when determining the threshold relationship between the count rate and the preset count rate, the threshold relationship between the current transmittance of the light intensity modulation structure and the first transmittance can be correspondingly determined. The threshold relationship between the count rate and the preset count rate includes the size relationship between the count rate and the preset count rate, as well as the count rate difference between the two.

[0144] Step S22: determining a first light transmittance required by the light intensity adjustment structure according to the threshold relationship.

[0145] It should be understood that, when determining the threshold relationship between the counting rate and the preset counting rate, the threshold relationship between the current transmittance of the light intensity adjustment structure and the first transmittance can be determined based on the threshold relationship; further, the first transmittance required by the light intensity adjustment structure can be determined based on the current transmittance of the light intensity adjustment structure and the threshold relationship.

[0146] In the specific implementation, in order to ensure that the counting rate is the preset counting rate, a continuously adjustable driving voltage needs to be set when setting the driving voltage, and the transmittance of the corresponding light intensity adjustment structure is also a continuously changing value, with a maximum value of a. max , the minimum value is a min . Reference Figure 11 During the imaging process, the initial transmittance of the light intensity modulation structure is the maximum value a max , and monitor the count rate of the device in real time. When the count rate is greater than or less than the preset count rate, the transmittance of the light intensity modulation structure is reduced or increased by adjusting the voltage of the driving signal to maintain the count rate of the device at the preset count rate. The actual light intensity is calculated by the actual count rate of the SPAD and the actual transmittance a of the light intensity modulation structure: I = C / a / PDE. During the adjustment process of this scheme, when the transmittance of the light intensity modulation structure is not adjusted, the maximum detectable photon rate is I s1 =C s / a max / PDE, where C S is the saturation count rate of the SPAD device. By adjusting the transmittance of the light intensity modulation structure of this scheme, the maximum photon detection rate can be increased to I sn =C s / a min / PDE, dynamic range increased by a max / a min times, further improving the range of light intensity that the SPAD device can receive.

[0147] The fifth embodiment of the light transmittance adjusting method of the present application is proposed based on any one of the first to fourth embodiments of the above-mentioned light transmittance adjusting method.

[0148] Reference Figure 12 , Figure 12 This is a flow chart of the fifth embodiment of the transmittance adjustment method proposed in this application.

[0149] In this embodiment, before step S10, the following steps are further included:

[0150] Step S101: detecting a driving mode of the light intensity adjustment structure.

[0151] It should be understood that the light intensity modulation structure is a structure arranged above the device body for adjusting the amount of light entering the device body. The light intensity modulation structure is driven by a driving signal input by a driving structure. However, in the actual driving process, a plurality of SPAD devices are arranged in the SPAD device array. Therefore, in the process of setting the light intensity modulation structure, the light intensity modulation structure can be set as a whole and directly set on the pixels corresponding to all SPAD devices. The transmittance of the entire light intensity modulation structure can be uniformly adjusted, that is, a driving signal can be used to adjust the transmittance on the pixels corresponding to all SPAD devices, and the light intensity modulation structures on the pixels corresponding to all SPAD devices are directly connected to the same output pin of the driving structure; of course, the light intensity modulation structure can also be set as a sub-regulation structure with the same number of SPAD devices, and the sub-regulation structure on the pixel corresponding to each SPAD device can be adjusted separately for the SPAD device, that is, the sub-regulation structure on the pixel corresponding to each SPAD device is respectively connected to different output pins of the driving structure.

[0152] In a specific implementation, the driving mode of the light intensity modulation structure can be determined by determining the connection relationship between the driving structure and the light intensity modulation structure.

[0153] Step S102: when the driving mode is a global driving mode, obtaining the count rates of all device bodies in the SPAD device array.

[0154] It should be noted that, referring to Figure 13 The global drive mode is a drive mode in which the light intensity modulation structures within each SPAD device are driven using the same drive signal. Under the global drive mode, the light intensity modulation structures at the upper side of each SPAD device have the same transmittance. While the transmittance of a single pixel cannot be adjusted individually under the global drive mode, it can be adjusted uniformly for the corresponding pixels of all SPAD devices.

[0155] It should be understood that the specific adjustment process needs to consider the overall adjustment trend of all device bodies in the SPAD device array, and then adjust the transmittance of the light intensity modulation structure to achieve the best overall imaging effect. Therefore, it is necessary to obtain the count rate of each device body.

[0156] Step S103: obtaining a threshold ratio of the counting rates greater than a preset counting rate in the counting rates.

[0157] It should be noted that when the transmittance of the light intensity modulation structure is driven in a global driving manner, it is necessary to consider the overall proportion of the count rates of all device bodies. In this embodiment, the proportion of the count rates in the count rate set formed by the count rates corresponding to the respective device bodies that is greater than the threshold value of the preset count rate can be selected. If the threshold proportion is high, it indicates that the count rates of most of the SPAD devices in the SPAD device array are high, and in this case, the transmittance of the light intensity modulation structure needs to be reduced; conversely, if the threshold proportion is low, it indicates that the count rates of most of the SPAD devices in the SPAD device array are low, and in this case, the transmittance of the light intensity modulation structure needs to be increased.

[0158] Step S104: when the threshold ratio is greater than a first preset ratio, the light intensity adjustment structure is driven in sequence by using a plurality of driving signals with gradually decreasing amplitudes.

[0159] It should be noted that the first preset ratio is a ratio pre-set to determine whether the overall count rate of all SPAD devices included in the SPAD device array is high. If the threshold ratio is greater than the first preset ratio, it indicates that the count rate of most SPAD devices in the SPAD device array is high. By setting multiple drive signals, the light intensity modulation structure can be sequentially driven with drive signals of gradually decreasing amplitudes, thereby gradually reducing the transmittance of the light intensity modulation structure until the threshold ratio is no longer greater than the first preset ratio.

[0160] Step S105 : when the threshold ratio is less than a second preset ratio, sequentially driving the light intensity adjustment structure using a plurality of driving signals with gradually increasing amplitudes; the first preset ratio is greater than the second preset ratio.

[0161] It should be noted that the second preset ratio is a ratio pre-set to determine whether the overall count rate of all SPAD devices included in the SPAD device array is low. If the threshold ratio is less than the second preset ratio, it indicates that the count rate of most SPAD devices in the SPAD device array is low. By setting multiple drive signals, the light intensity modulation structure can be sequentially driven with drive signals of gradually increasing amplitudes, thereby gradually increasing the transmittance of the light intensity modulation structure until the threshold ratio is no longer less than the second preset ratio.

[0162] Of course, when the threshold ratio is between the second preset ratio and the first preset ratio, it indicates that the counting rates of most SPAD devices in the SPAD device array are within the normal imaging range, and there is no need to adjust the transmittance of the light intensity modulation structure.

[0163] In this embodiment, after step S101, the following steps are further included:

[0164] Step S106: When the driving mode is an independent driving mode, executing the step of obtaining the counting rate of the device body.

[0165] It should be noted that the independent driving mode is a driving mode in which the light intensity modulation structure in each of the SPAD devices is driven by the driving signal required by each of the light intensity modulation structures. Figure 14 ,exist Figure 14 The transmittance of the light intensity tuning structure at the upper side of each SPAD device in the SPAD device array can be adjusted individually. In the specific transmittance adjustment process, the adjustment methods in the first to fourth embodiments above can be directly used to adjust the transmittance of the light intensity tuning structure at the upper side of the SPAD device, which will not be repeated here.

[0166] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0167] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

[0168] The above descriptions are only some embodiments of the present application and do not limit the scope of the present application. All equivalent structural transformations made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect application in other related technical fields are included in the scope of protection of the present application.

Claims

1. A light transmittance adjustment method, characterized in that: Applied to driving structures within SPAD device arrays; The SPAD device array includes: the driving structure and a plurality of SPAD devices; the SPAD device includes: a device body and a light intensity modulation structure, the light intensity modulation structure is connected to the driving structure, and the light intensity modulation structure is arranged on the light incident side of the device body; The light transmittance adjustment method comprises: Obtaining a count rate of the device body; determining a first light transmittance required by the light intensity modulation structure based on the count rate when the count rate of the device body does not meet a preset condition; The light intensity adjustment structure is driven by a driving signal corresponding to the first light transmittance.

2. The light transmittance adjustment method according to claim 1, wherein: The first light transmittance is a light transmittance corresponding to adjusting the counting rate to be within a preset counting rate threshold range; The preset condition is not met when the count rate is not within a preset count rate threshold range; The step of driving the light intensity adjustment structure using a driving signal corresponding to the first light transmittance includes: detecting the number of driving signals set for driving the light intensity adjustment structure during the transmittance adjustment process; When the number of the driving signals is two, the light intensity adjustment structure is driven by the driving signal corresponding to the first light transmittance.

3. The light transmittance adjustment method according to claim 2, wherein: After detecting the number of driving signals set for driving the light intensity adjustment structure during the transmittance adjustment process, the method further includes: When the number of the driving signals is greater than two, obtaining a plurality of driving signals required to adjust the transmittance of the light intensity adjustment structure to the first transmittance; The light intensity adjustment structure is driven in sequence using the amplitudes of the multiple driving signals.

4. The light transmittance adjustment method according to any one of claims 2 to 3, wherein: When the count rate of the device body does not meet a preset condition, determining the first transmittance required by the light intensity modulation structure based on the count rate, the method further includes: Obtaining a photon counting resolution requirement of the device body, and setting a lower endpoint of the preset count rate threshold range according to the photon counting resolution requirement; Obtaining a saturation count rate of the device body, and setting an upper endpoint of the preset count rate threshold range according to the saturation count rate; The preset count rate threshold range is set according to the lower endpoint and the upper endpoint.

5. The light transmittance adjustment method according to claim 4, wherein: The obtaining of the saturation count rate of the device body and setting the upper endpoint of the preset count rate threshold range according to the saturation count rate includes: Obtaining a saturation count rate of the device body, and setting an initial upper endpoint of the preset count rate threshold range according to the saturation count rate; the initial upper endpoint being the upper endpoint of the preset count rate threshold range before imaging the device body; detecting a count rate of each of the device bodies and a corresponding second light transmittance of the light intensity modulation structure during an imaging process of each of the device bodies; determining a light intensity value input to each of the device bodies according to the count rate, the second transmittance, and a second mapping relationship; wherein the second mapping relationship is a mapping relationship between the count rate of the device body, the transmittance of the light intensity modulation structure, and the light intensity value received by the light intensity modulation structure; Obtaining a light intensity change value of the device body according to the light intensity values ​​of each of the device bodies detected in at least two cycles; According to the light intensity change value of each device body, the corresponding initial upper limit endpoint is adjusted to obtain the upper limit endpoint of each preset count rate threshold range.

6. The light transmittance adjustment method according to claim 1, wherein: The preset condition is not satisfied when the counting rate is not the preset counting rate, and the first light transmittance is the light transmittance required for the light intensity adjustment structure to adjust the counting rate to the preset counting rate; The setting parameters of the preset count rate include: the saturation count rate of the device body; When the count rate of the device body does not meet a preset condition, determining the first transmittance required by the light intensity modulation structure based on the count rate includes: determining a threshold relationship between the count rate and the preset count rate when the count rate of the device body is not a preset count rate; A first light transmittance required by the light intensity adjustment structure is determined according to the threshold relationship.

7. The light transmittance adjustment method according to claim 1, wherein: Before obtaining the count rate of the device body, the method further includes: detecting a driving mode of the light intensity modulation structure; When the driving mode is a global driving mode, the count rates of all device bodies in the SPAD device array are obtained; the global driving mode is a driving mode in which the light intensity adjustment structure in each of the SPAD devices is driven by the same driving signal; Obtaining a threshold ratio of the count rates greater than a preset count rate among the count rates; When the threshold ratio is greater than a first preset ratio, the light intensity adjustment structure is driven in sequence by using a plurality of driving signals with gradually decreasing amplitudes; When the threshold ratio is less than a second preset ratio, the light intensity adjustment structure is sequentially driven by a plurality of driving signals with gradually increasing amplitudes; and the first preset ratio is greater than the second preset ratio.

8. The light transmittance adjustment method according to claim 7, wherein: After detecting the driving mode of the light intensity adjustment structure, the method further includes: When the driving mode is an independent driving mode, performing the step of obtaining the counting rate of the device body; The independent driving mode is a driving mode in which the light intensity modulation structure in each of the SPAD devices is driven by a driving signal required by each of the light intensity modulation structures.

9. A SPAD device array, characterized in that: include: Driving structure and multiple SPAD devices; The SPAD device comprises: a device body and a light intensity modulation structure, wherein the light intensity modulation structure is connected to the driving structure and is arranged on the light incident side of the device body; the device bodies of the SPADs are isolated by an isolation structure; The driving structure is used to execute the transmittance adjustment method according to any one of claims 1 to 8.

10. The SPAD device array according to claim 9, wherein: The light intensity modulation structure includes: a polarizer, a common electrode layer, a liquid crystal layer, a thin film transistor layer and an analyzer arranged from top to bottom; The polarizer is arranged above the device body; the common electrode layer and the thin film transistor layer are connected to the driving structure.

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