DToF module and dToF module control method

Abstract

The embodiment of the invention provides a dToF module and a control method of the dToF module. The dToF module comprises a temperature sensor and a data processor; the temperature sensor is configured to collect the temperature of the dToF module when the dToF module works; the data processor is configured to obtain a first distance measurement result of the dToF module for a calibration object at a preset distance when the dToF module is at different temperatures, and generate a distance measurement temperature drift curve of the dToF module according to the first distance measurement result, the preset distance and the temperature collected by the temperature sensor.

Description

Technical Field

[0001] The present disclosure relates to the technical field of ranging, and particularly to a dToF module and a control method for the dToF module. Background Art

[0002] Direct Time of Flight (dToF) ranging uses a laser emitter to emit laser pulses that irradiate an object to be measured and then reflect back. A Single Photon Avalanche Diode (SPAD) senses and generates an electrical pulse, and a Time Digital Convertor (TDC) converts the time difference between the transmitted and received electrical pulses into a digital signal. A ranging method for obtaining the distance of the object to be measured through histogram statistical analysis.

[0003] The dToF system converts the flight time of photons into an electrical signal for distance measurement. When the temperature of the dToF system changes, the measured distance will deviate with temperature changes, that is, the measured distance drifts with temperature. To improve the stability of the dToF system, it is necessary to obtain the characteristic curve of the ranging characteristics of the dToF system with temperature changes to correct the measured distance of the dToF system. Summary of the Invention

[0004] In view of this, embodiments of the present disclosure provide a dToF module and a control method for the dToF module.

[0005] To achieve the above object, the technical solution of the present disclosure is realized as follows:

[0006] In a first aspect, embodiments of the present disclosure provide a dToF module, including a temperature sensor and a data processor; the temperature sensor is configured to collect the temperature of the dToF module when the dToF module is operating; the data processor is configured to obtain a first ranging result of the dToF module for a calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

[0007] In some embodiments, the data processor is further configured to obtain a second ranging result of the dToF module for a target object, and correct the second ranging result according to the temperature of the dToF module and the ranging temperature drift curve to obtain a first correction result.

[0008] In some embodiments, the dToF module further includes a time digital converter; the temperature sensor is configured to obtain the temperature of the time digital converter or / and the data processor when the dToF module is operating.

[0009] In some embodiments, the data processor is further configured to: when obtaining the first ranging result, simultaneously obtain the number of valid delay units in the time-to-digital converter, and generate an accuracy temperature drift curve of the time-to-digital converter according to the first ranging result, the preset distance, the number of valid delay units, and the temperature collected by the temperature sensor.

[0010] In some embodiments, the data processor is further configured to: obtain a second ranging result of the dToF module for the target object, simultaneously obtain the number of valid delay units in the time-to-digital converter, perform accuracy correction on the time-to-digital converter according to the accuracy temperature drift curve to obtain a corrected accuracy, and then correct the second ranging result according to the temperature collected by the temperature sensor, the number of valid delay units, and the corrected accuracy to obtain a second corrected result.

[0011] In some embodiments, the distance between the temperature sensor and the time-to-digital converter and / or the data processor is less than a preset threshold.

[0012] In some embodiments, the time-to-digital converter includes a plurality of time-to-digital conversion units, and the temperature sensor includes a plurality of temperature sensing units; wherein, each temperature sensing unit collects the temperature of at least one of the time-to-digital conversion units, and the distance between the temperature sensing unit and the time-to-digital conversion unit corresponding to the collected temperature is less than a preset threshold.

[0013] In some embodiments, the plurality of time-to-digital conversion units are arranged in an array in a preset plane, and the plurality of temperature sensing units are distributed on the periphery of the array of the time-to-digital conversion units.

[0014] In some embodiments, the data processor is configured to: when obtaining the first ranging result, simultaneously obtain the number of valid delay units in the time-to-digital conversion unit corresponding to the temperature collected by each temperature sensing unit, and generate an accuracy temperature drift curve of each time-to-digital conversion unit according to the first ranging result, the preset distance, the number of valid delay units, and the temperature collected by the temperature sensing unit.

[0015] In a second aspect, an embodiment of the present disclosure provides a control method for a dToF module, where the dToF module includes: a temperature sensor and a data processor; the control method includes: controlling the temperature sensor to collect the temperature of the dToF module when the dToF module is working; controlling the data processor to obtain a first ranging result of the dToF module for a calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

[0016] Embodiments of the present disclosure provide a dToF module and a control method for the dToF module. The dToF module includes a temperature sensor and a data processor; the temperature sensor is configured to collect the temperature of the dToF module when the dToF module is operating; the data processor is configured to obtain a first ranging result of the dToF module for a preset distance calibration object at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor. The dToF module provided by the embodiments of the present disclosure can sense the change in its own temperature caused by power-on operation through the temperature sensor and collect the temperature of the dToF module in real time, and then generate the ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor. This process does not require placing the dToF module in a temperature-changing device, which not only reduces the test cost but also saves a large amount of test time. Only by collecting the temperature of the dToF module when it is operating and the first ranging results at different temperatures can the ranging temperature drift curve of the dToF module be generated, which has the advantages of low cost and short test time. Description of the Drawings

[0017] Figure 1 Schematic structural diagram of the dToF module provided by the embodiments of the present disclosure Figure 1 ;

[0018] Figure 2 Schematic diagram of the principle for the dToF module provided by the embodiments of the present disclosure to obtain the ranging temperature drift curve;

[0019] Figure 3 Schematic histogram diagram corresponding to the first ranging result provided by the embodiments of the present disclosure;

[0020] Figure 4 Schematic structural diagram of the dToF module provided by the embodiments of the present disclosure Figure 2 ;

[0021] Figure 5 Schematic diagram of the steps of a control method for a dToF module provided by the embodiments of the present disclosure. Detailed Embodiments

[0022] Next, the technical solutions in the embodiments of the present disclosure will be clearly and completely described in conjunction with the embodiments of the present disclosure and the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

[0023] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present disclosure. However, it will be apparent to one of ordinary skill in the art that the present disclosure may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the present disclosure; that is, not all features of actual embodiments are described herein, and well-known functions and constructions are not described in detail.

[0024] In the drawings, for the sake of clarity, the dimensions of layers, regions, elements, and their relative dimensions may be exaggerated. Throughout the drawings, like reference numerals indicate like elements.

[0025] It should be understood that when an element or layer is referred to as being “on,” “adjacent to,” “connected to,” or “coupled to” another element or layer, it can be directly on, adjacent to, connected to, or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly adjacent to,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers, and / or sections, these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Thus, a first element, component, region, layer, or section discussed below may be referred to as a second element, component, region, layer, or section without departing from the teachings of the present disclosure. And when a second element, component, region, layer, or section is discussed, it does not necessarily imply that a first element, component, region, layer, or section exists in the present disclosure.

[0026] Spatial relationship terms such as “under,” “below,” “beneath,” “underneath,” “above,” “over,” etc. are used herein for convenience in describing the relationship of one element or feature to another element or feature shown in the figures. It should be understood that, in addition to the orientation shown in the figures, spatial relationship terms are intended to include different orientations of the device in use and operation. For example, if the device in the figures is flipped, then an element or feature described as “under” or “beneath” or “underneath” another element or feature will be oriented “over” the other element or feature. Thus, the exemplary terms “under” and “beneath” can include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatial descriptors used herein are to be interpreted accordingly.

[0027] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present disclosure. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, specify the presence of the stated features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. As used herein, the term "and / or" includes any and all combinations of the related listed items.

[0028] To thoroughly understand the present disclosure, detailed steps and structures will be presented in the following description to illustrate the technical solutions of the present disclosure. The preferred embodiments of the present disclosure are described in detail below. However, in addition to these detailed descriptions, the present disclosure may have other embodiments.

[0029] When the dToF module is used for ranging, its ranging performance is affected by temperature. Specifically, the ranging results of the dToF module for the same target will drift to varying degrees with temperature changes, resulting in unreliable measurement results. Therefore, in the related art, generally in the test stage, the dToF module is placed in a temperature-changing device, the ambient temperature of the dToF module is controlled by the temperature-changing device, and the measurement results of the dToF module for the same target at different temperatures are recorded to obtain the temperature drift curve of the dToF module. However, the temperature-changing device has a large investment and slow temperature change, resulting in high costs and long test times.

[0030] In view of this, an embodiment of the present disclosure provides a dToF module, including a temperature sensor and a data processor; the temperature sensor is configured to collect the temperature of the dToF module when the dToF module is working; the data processor is configured to obtain the first ranging result of the dToF module for a calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

[0031] Figure 1 Structural schematic of the dToF module provided by the embodiment of the present disclosure Figure 1 . Refer to Figure 1 , the dToF module includes a temperature sensor 110 and a data processor 120. During the power-on operation of the dToF module, temperature changes will occur due to its own power consumption and heat generation. The temperature sensor 110 can collect the temperature of the dToF module during operation, and the data processor can obtain the first ranging result d1 of the dToF module for the calibration object at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the difference between the first ranging result d1 and the preset distance d0 and the temperature of the dToF module, as shown in the following formula (1):

[0032] Δd (T) = d1 - d0 (1);

[0033] Wherein, Δd (T) is the temperature drift amount of the dToF module for ranging at temperature T.

[0034] It should be noted that the ranging temperature drift curve determined by Equation (1) is applicable to the case where the distance to be measured of the target object is close to the preset distance d0. Exemplarily, when the distance to be measured D differs from the preset distance d0 by no more than 1 m, 3 m, or 5 m, it can be considered that the distance to be measured D is close to the preset distance d0, and specifically, it can be determined according to the actual measurement situation.

[0035] When the distance to be measured D differs greatly from the preset distance d0, exemparily, when the distance to be measured D differs from the preset distance d0 by more than 5 m or 10 m (specifically, it can be determined according to the actual situation), the ranging temperature drift curve of the dToF module can be generated according to the ratio of the first ranging result d1 to the preset distance d0 and the temperature of the dToF module, as shown in Equation (2) below:

[0036] α (T) = d1 / d0 (2);

[0037] It can be understood that when the distance to be measured D is close to the preset distance d0, the ranging temperature drift curve of Equation (1) is selected to correct the ranging result of the target object; when the distance to be measured D differs greatly from the preset distance d0, the ranging temperature drift curve of Equation (2) is selected to correct the ranging result of the target object. In addition, when using Equation (1) or Equation (2) to correct the ranging result of the target object, the correction formulas for the ranging result may be different.

[0038] The dToF module provided by the embodiments of the present disclosure senses the self-temperature change of the dToF module caused by power-on operation through a temperature sensor and collects the temperature of the dToF module in real time. Then, according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor, the ranging temperature drift curve of the dToF module can be generated. This process does not require placing the dToF module in a variable-temperature device, which not only reduces the test cost but also saves a large amount of test time. Only by collecting the temperature of the dToF module and the first ranging results at different temperatures when the dToF module is working can the ranging temperature drift curve of the dToF module be generated, which has the advantages of low cost and short test time.

[0039] It should be noted that in the present disclosure, the preset distance d0 of the calibration object can be understood as the distance between the surface of the dToF module and the calibration object. In the embodiments of the present disclosure, the calibration object can have the characteristics of stable form, and is not easily affected by external factors (such as wind, vibration, etc.) and changes; it has a high reflectivity, which helps to ensure that the dToF module can receive a strong enough reflected light signal, thereby improving the accuracy and reliability of calibration; it has the characteristic of uniform surface, avoiding the difference in light signal reflection caused by uneven surface or uneven material. The calibration object with the above characteristics can improve the accuracy of calibration and the accuracy of the ranging temperature drift curve. In addition, the value of the preset distance in the embodiments of the present disclosure can be set according to actual situations and is not specifically limited herein.

[0040] In some embodiments, the data processor is further configured to obtain a second ranging result of the dToF module for the target object, and correct the second ranging result according to the temperature of the dToF module and the ranging temperature drift curve to obtain a first corrected result.

[0041] In some embodiments, the data processor 120 is configured to obtain a second ranging result d2 of the dToF module for the target object, and correct the second ranging result d2 according to the temperature of the dToF module collected by the temperature sensor 110 and the ranging temperature drift curve to obtain a first corrected result D1 (that is, the corrected second ranging result).

[0042] In a specific embodiment, the temperature collected by the temperature sensor is T. When the difference between the distance D to be measured of the target object and the preset distance d0 is small, such as less than 3m, the second ranging result d2 can be corrected by the ranging temperature drift curve as shown in Equation (1) to obtain the first corrected result D1, and the correction formula is as follows Equation (3):

[0043] D1 = d2 - △d (T) = d2 - (d1 - d0) (3);

[0044] In another specific embodiment, the temperature collected by the temperature sensor is T. When the difference between the distance D to be measured of the target object and the preset distance d0 is large, such as greater than 5m, the second ranging result d2 can be corrected by the ranging temperature drift curve as shown in Equation (2) to obtain the first corrected result D1, and the correction formula is as follows Equation (4):

[0045] D1 = d2 / α (T) = d2 / (d1 / d0) = d2 * d0 / d1 (4);

[0046] In the embodiments of the present disclosure, according to the difference between the distance D to be measured and the preset distance d0, the ranging result can be corrected by the ranging temperature drift curve of formula (1) or formula (2). In this way, the influence of the temperature change during the operation of the dToF module on the ranging result of the dToF module can be reduced, and the reliability of the temperature drift correction for the dToF module can be improved.

[0047] In some embodiments, the dToF module further includes a time-to-digital converter; the temperature sensor is configured to obtain the temperature of the time-to-digital converter or / and the data processor when the dToF module is operating.

[0048] Figure 2 It is a schematic diagram of the principle for the dToF module provided by the embodiments of the present disclosure to obtain the ranging temperature drift curve. Refer to Figure 1 and Figure 2 , the dToF module further includes a time-to-digital converter 130, a laser emitter 140, and an acquisition array 150. Among them, the laser emitter 140 can emit detection light, and the detection light irradiates on the calibration object and is reflected to the acquisition array 150. The time-to-digital converter 130 is configured to measure the photon flight time of the emitted and reflected detection light, and the data processor 120 is configured to generate a histogram based on the photon flight time of the photons received by the acquisition array 150 during the measurement time, and determine the first ranging result according to the histogram. It should be noted that the acquisition array can be an array composed of photosensitive elements, such as an SPAD array, an APD (Avalanche Photo Diode) array, or an SiPM (Silicon Photo Multiplier) array.

[0049] In some embodiments, the data processor 120 and the time-to-digital converter 130 are key components in the dToF module, and the performance of the data processor 120 and the time-to-digital converter 130 is susceptible to temperature influence and temperature drift occurs, thus affecting the accuracy of the measurement result of the dToF module. Specifically, the temperature change will affect the operation accuracy and stability of the data processor, resulting in an increase in signal processing errors, and further affecting the accuracy of the ranging result. The temperature change will also cause the accuracy (time resolution) of the time-to-digital converter to change, resulting in an error in the measured photon flight time, and further affecting the accuracy of the ranging result.

[0050] Since the time-to-digital converter 130 and the data processor 120 are greatly affected by temperature, which in turn has a great impact on the ranging result, and the components that consume power and generate heat during the operation of the dToF module are mainly the time-to-digital converter 130 and the data processor 120, the temperature sensor 110 can be configured to obtain the temperature of the time-to-digital converter 130 or / and the data processor 120, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature of the time-to-digital converter 130 or / and the data processor 120 collected by the temperature sensor. In this way, the reliability and accuracy of the ranging temperature drift curve can be improved.

[0051] In some embodiments, the data processor is further configured to: when obtaining the first ranging result, simultaneously obtain the number of valid delay units in the time-to-digital converter, and generate an accuracy temperature drift curve of the time-to-digital converter according to the first ranging result, the preset distance, the number of valid delay units, and the temperature collected by the temperature sensor.

[0052] It should be noted that the "valid delay unit" refers to the delay unit that flips and outputs a valid signal to contribute to the time measured by the time-to-digital converter when obtaining the first ranging result. Figure 3 This is a schematic diagram of the histogram corresponding to the first ranging result provided by the embodiments of the present disclosure. Refer to Figure 3 , the horizontal axis of the histogram is time t, and the horizontal axis t is divided into multiple time bins with the same width; the vertical axis is the photon count value n. As Figure 3 shown, the first ranging result is obtained as d1, and this ranging result (d1) is reflected and calculated through the photon flight time statistical histogram generated by the data processor. The peak of the statistical wave peak in the histogram is located at the N1th time bin, so the number of valid delay units corresponding to obtaining the first ranging result d1 is N1.

[0053] According to the dToF ranging principle: where t1 is the photon flight time corresponding to the first ranging result d1, and c is the speed of light. The photon flight time corresponding to the first ranging result d1 can be deduced as follows in Equation (5):

[0054]

[0055] Similarly, according to the dToF ranging principle: where d0 is the preset distance of the calibration object, t0 is the theoretical photon flight time corresponding to the preset distance d0 when applying the dToF ranging method, and c is the speed of light. The theoretical photon flight time corresponding to the preset distance d0 can be deduced as follows in Equation (6):

[0056]

[0057] In some embodiments, the data processor 120 is configured to generate an accuracy temperature drift curve of the time-to-digital converter according to the first ranging result, a preset distance, the number of effective delay units, and the temperature collected by the temperature sensor, as shown in the following formula (7):

[0058]

[0059] where Δt (T) is the temperature drift amount of the accuracy of the time-to-digital converter at temperature T, T is the temperature collected by the temperature sensor, d1 is the above-mentioned first ranging result, d0 is the preset distance, c is the speed of light, and N1 is the number of effective delay units in the time-to-digital converter when obtaining the first ranging result d1.

[0060] In some embodiments, the data processor is further configured to: obtain a second ranging result of the dToF module for the target object, and at the same time obtain the number of effective delay units in the time-to-digital converter, and perform accuracy correction on the time-to-digital converter according to the accuracy temperature drift curve to obtain a corrected accuracy, and then correct the second ranging result according to the temperature collected by the temperature sensor, the number of effective delay units, and the corrected accuracy to obtain a second corrected result.

[0061] In a specific embodiment, the temperature collected by the temperature sensor is T, and the data processor 120 corrects the second ranging result d2 according to the temperature drift accuracy curve and the number of effective delay units to obtain a second corrected result (that is, the corrected second ranging result). Specifically, the second ranging result d2 is reflected and calculated through the photon flight time statistical histogram generated by the data processor. The peak value of the statistical wave peak in the histogram is located at the N2th time bin, then the number of effective delay units when obtaining the second ranging result d2 is N2.

[0062] In a specific embodiment, the data processor performs accuracy correction on the time-to-digital converter according to the accuracy temperature drift curve to obtain a corrected accuracy, which may include:

[0063] Obtain the preset initial accuracy of the time-to-digital converter;

[0064] Use the accuracy temperature drift curve to perform accuracy correction on the preset initial accuracy to obtain a corrected accuracy.

[0065] Among them, the preset initial accuracy of the time-to-digital converter refers to the initial accuracy set during the manufacturing process of the time-to-digital converter. This initial accuracy is one of the factory parameters of the time-to-digital converter and can be stored or recorded in the storage space of the dToF module or marked on the surface of the module.

[0066] Exemplarily, the preset initial accuracy of the time-to-digital converter is t 预, the temperature of the dToF module collected by the temperature sensor is T. After performing accuracy correction on the time-to-digital converter through the precision temperature drift curve, the corrected accuracy t is obtained. 校 , as shown in the following formula (8):

[0067]

[0068] In a specific embodiment, the second correction result D2 is as shown in the following formula (9):

[0069]

[0070] Wherein, t2 is the photon flight time corresponding to the second correction result D2 when using the dToF ranging method, c is the speed of light, N2 is the number of effective delay units in the time-to-digital converter when obtaining the second ranging result, and t 预 is the preset initial accuracy set at the factory of the time-to-digital converter, and t 校 is the corrected accuracy of the time-to-digital converter after being corrected by the precision temperature drift curve.

[0071] In the embodiments of the present disclosure, the reason why the ranging results of the dToF module for the same target vary with temperature is mainly that temperature affects the electrical signal transmission delay of the circuits inside the dToF module (especially the time-to-digital converter), thereby affecting the time accuracy of the time-to-digital converter and causing the ranging results to drift. Therefore, in this embodiment, by collecting the temperature of the time-to-digital converter to generate the precision temperature drift curve of the time-to-digital converter and performing accuracy correction according to the precision temperature drift curve to obtain the corrected accuracy, it is possible to further avoid interference from external factors on the temperature drift correction and improve the accuracy of the temperature drift correction of the dToF module.

[0072] In some embodiments, the distance between the temperature sensor and the time-to-digital converter and / or the data processor is less than a preset threshold.

[0073] In some embodiments, the distance between the temperature sensor 110 and the time-to-digital converter 130 and / or the data processor 120 is less than a preset threshold, where the preset threshold can be set to the maximum sensing distance of the temperature sensor. In this way, the temperature sensor can more fully collect the temperature of the time-to-digital converter 130 and / or the data processor 120, and the temperature of the dToF module collected can be more accurate, which can improve the accuracy of the ranging temperature drift curve and / or the precision temperature drift curve, thereby improving the reliability of the ranging results (the first correction result or the second correction result) of the dToF module.

[0074] In some other embodiments, the distance between the temperature sensor 110 and the laser emitter 140 and the acquisition array 150 is greater than a set value, so as to avoid the temperature rise of the laser emitter 140 and the acquisition array 150 after the dToF module is powered on, which affects the temperature of the time-to-digital converter 130 and / or the data processor 120 collected by the temperature sensor 110. In this way, the accuracy of the ranging temperature drift curve and / or the accuracy temperature drift curve can be improved, thereby improving the reliability of the ranging result (the first correction result or the second correction result) of the dToF module. It should be noted that the set value is greater than a preset threshold.

[0075] In some embodiments, the time-to-digital converter includes a plurality of time-to-digital conversion units, and the temperature sensor includes a plurality of temperature sensing units; wherein, each temperature sensing unit collects the temperature of at least one time-to-digital conversion unit, and the distance between the temperature sensing unit and the time-to-digital conversion unit corresponding to the collected temperature is less than a preset threshold.

[0076] In the embodiments of the present disclosure, the time-to-digital converter includes a plurality of time-to-digital conversion units, which means that the dToF module can perform multi-channel measurement to improve the ranging accuracy. Correspondingly, in the embodiments of the present disclosure, the temperature sensor is set to include a plurality of temperature sensing units, so that the plurality of temperature sensing units can respectively perform accurate temperature measurement on the plurality of time-to-digital conversion units, thereby respectively obtaining the ranging temperature drift curves of multiple channels or the accuracy temperature drift curves of multiple time-to-digital conversion units, further improving the ranging accuracy.

[0077] In some embodiments, the temperature sensing unit can have the function of multi-point measurement. In this way, the temperature sensing unit can collect the temperature of at least one time-to-digital conversion unit to form a sub-region measurement temperature of the time-to-digital converter. The temperature acquisition region is wider and more sufficient, and the number of components constituting the dToF module is reduced, simplifying the design of the dToF module and reducing the hardware cost and wiring complexity.

[0078] In some other embodiments, the plurality of time-to-digital conversion units in the time-to-digital converter can be divided into a plurality of time-to-digital conversion regions, and the heat of the time-to-digital conversion units in the same time-to-digital conversion region is transferred to each other, so that the time-to-digital conversion units in the same time-to-digital conversion region have substantially the same temperature. Therefore, the temperature sensing unit can be configured to collect the temperature of the time-to-digital conversion units in the corresponding time-to-digital conversion region to reduce the number of temperature sensing units.

[0079] Figure 4 Structural schematic of the dToF module provided by the embodiments of the present disclosure Figure 2 See Figure 4, Exemplarily, the dToF module may include 10 time-to-digital conversion units (TDC1 to TDC10), and the temperature sensor may include 6 temperature sensing units (temperature sensing unit 111 to temperature sensing unit 116). Figure 4 Among the 6 temperature sensing units shown, the temperature sensing unit 111 is configured to collect the temperatures of TDC1 and TDC2, the temperature sensing unit 112 is configured to collect the temperatures of TDC3 and TDC4, the temperature sensing unit 113 is configured to collect the temperature of TDC5, the temperature sensing unit 114 is configured to collect the temperatures of TDC6 and TDC7, the temperature sensing unit 115 is configured to collect the temperatures of TDC8 and TDC9, and the temperature sensing unit 116 is configured to collect the temperature of TDC10.

[0080] It should be noted that Figure 4 the number of time-to-digital conversion units, the number of temperature sensing units, and the number of time-to-digital conversion units collected by each temperature sensing unit are only exemplary descriptions, and the present disclosure does not impose any restrictions on this.

[0081] In some embodiments, the number of temperature sensing units may be the same as the number of time-to-digital conversion units. In this case, each temperature sensing unit respectively collects the temperatures of different time-to-digital conversion units. In this case, the temperature sensing unit may be a contact temperature sensor, that is, the temperature sensing unit is in direct contact with the surface of the corresponding time-to-digital conversion unit to be collected, that is, the distance between the temperature sensing unit and the corresponding time-to-digital conversion unit to be collected is equal to 0.

[0082] In other embodiments, the number of temperature sensing units may be less than the number of time-to-digital conversion units. In this case, at least one temperature sensing unit needs to collect the temperatures of at least two time-to-digital conversion units. In this case, the temperature sensing unit may be a non-contact temperature sensor, that is, there is a certain distance between the temperature sensing unit and the corresponding time-to-digital conversion unit to be collected and it is less than a preset threshold.

[0083] In some embodiments, multiple time-to-digital conversion units are arranged in an array in a preset plane, and multiple temperature sensing units are distributed on the periphery of the array of time-to-digital conversion units.

[0084] In some embodiments, multiple time-to-digital conversion units are arranged in an array in a preset plane. Specifically, the dToF module may include several rows or several columns of time-to-digital conversion units. In the present disclosure, the number of time-to-digital conversion units in different rows or different columns may be the same or different, and may be specifically set according to the size and shape of the internal circuit setting space of the dToF module. The present disclosure does not impose any restrictions on the number of time-to-digital conversion units in the same row or the same column.

[0085] In the embodiments of the present disclosure, the temperature sensing unit is arranged on the periphery of the array of the time-to-digital conversion unit, which is beneficial to the routing setting of the signal transmission lines of the time-to-digital conversion unit, reduces the length of the signal transmission lines of the time-to-digital conversion unit, thereby reducing the signal transmission delay, ensuring the measurement efficiency of the dToF module, and can also avoid the temperature collected by the temperature sensing unit being affected by other time-to-digital conversion units (the time-to-digital conversion units corresponding to other temperature sensing units), reducing the deviation of the temperature collected by the temperature sensor, and thus improving the reliability of the dToF module.

[0086] In some embodiments, the data processor is configured to: when obtaining the first ranging result, simultaneously obtain the number of effective delay units in the time-to-digital conversion unit corresponding to each temperature sensing unit for collecting temperature, and generate an accuracy temperature drift curve for each time-to-digital conversion unit according to the first ranging result, the preset distance, the number of effective delay units, and the temperature collected by the temperature sensing unit.

[0087] In some embodiments, the data processor may be configured to obtain the second ranging result of the dToF module for the target object, simultaneously obtain the number of effective delay units in each time-to-digital conversion unit, perform accuracy calibration on each time-to-digital conversion unit according to the accuracy temperature drift curve of each time-to-digital conversion unit to obtain the calibrated accuracy, and then correct the second ranging result according to the temperature of each time-to-digital conversion unit collected by the temperature sensor, the number of effective delay units in each time-to-digital conversion unit, and the corresponding calibrated accuracy to obtain the calibrated ranging result.

[0088] It can be understood that the method for obtaining the accuracy temperature drift curve of each time-to-digital conversion unit in the embodiments of the present disclosure may refer to the method for obtaining the accuracy temperature drift curve of the time-to-digital converter in the foregoing embodiments. Correspondingly, in the embodiments of the present disclosure, the method for correcting the second ranging result according to the temperature of each time-to-digital conversion unit collected by the temperature sensor, the number of effective delay units in each time-to-digital conversion unit, and the corresponding calibrated accuracy may also refer to the correction method in the foregoing embodiments. The difference between the two is only the reuse of the method, which will not be elaborated in the embodiments of the present disclosure.

[0089] The embodiments of the present disclosure further provide a control method for a dToF module. The dToF module includes: a temperature sensor and a data processor; the control method includes: controlling the temperature sensor to collect the temperature of the dToF module when the dToF module is working; controlling the data processor to obtain the first ranging result of the dToF module for the calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

[0090] Figure 5 It is a schematic diagram of the steps of a control method for a dToF module provided by the embodiments of the present disclosure. Refer to Figure 5, the control method includes the following steps:

[0091] S100: Control the temperature sensor to collect the temperature of the dToF module when the dToF module is working.

[0092] S200: Control the data processor to obtain the first ranging result of the dToF module for a preset distance calibration object at different temperatures.

[0093] S300: Control the data processor to generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

[0094] In some embodiments, the control method further includes: controlling the data processor to obtain a second ranging result of the dToF module for a target object, and correcting the second ranging result according to the temperature of the dToF module and the ranging temperature drift curve to obtain a first correction result.

[0095] In some embodiments, the dToF module further includes a time-to-digital converter; the control method further includes: controlling the temperature sensor to obtain the temperature of the time-to-digital converter or / and the data processor when the dToF module is working.

[0096] In some embodiments, the control method further includes: when the data processor obtains the first ranging result, controlling the data processor to simultaneously obtain the number of delay units in the time-to-digital converter, and generating an accuracy temperature drift curve of the time-to-digital converter according to the first ranging result, the preset distance, the number of effective delay units, and the temperature collected by the temperature sensor.

[0097] In some embodiments, the control method further includes: controlling the data processor to obtain a second ranging result of the dToF module for a target object, simultaneously obtaining the number of effective delay units in the time-to-digital converter, correcting the accuracy of the time-to-digital converter according to the accuracy temperature drift curve to obtain a corrected accuracy, and then correcting the second ranging result according to the temperature collected by the temperature sensor, the number of effective delay units, and the corrected accuracy to obtain a second correction result.

[0098] In some embodiments, the time-to-digital converter includes a plurality of time-to-digital conversion units, and the temperature sensor includes a plurality of temperature sensing units; the control method further includes: controlling each temperature sensing unit to collect the temperature of at least one time-to-digital conversion unit, and the distance between the temperature sensing unit and the time-to-digital conversion unit corresponding to the collected temperature is less than a preset threshold.

[0099] In some embodiments, the control method further includes: controlling the data processor to, when obtaining the first ranging result, simultaneously obtain the number of valid delay units in the time-to-digital conversion unit corresponding to each temperature sensing unit for collecting the temperature, and generate an accuracy temperature drift curve for each time-to-digital conversion unit according to the first ranging result, the preset distance, the number of valid delay units, and the temperature collected by the temperature sensing unit.

[0100] It should be noted here that the description of the control method of the above dToF module is similar to the description of the above dToF module embodiments, and has beneficial effects similar to those of the dToF module embodiments. For the technical details not disclosed in the embodiments of the control method of the dToF module of the present disclosure, please refer to the description of the dToF module embodiments of the present disclosure for understanding.

[0101] The embodiments of the present disclosure provide a dToF module and a control method for the dToF module. The dToF module includes a temperature sensor and a data processor; the temperature sensor is configured to collect the temperature of the dToF module when the dToF module is working; the data processor is configured to obtain the first ranging result of the dToF module for a calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor. The dToF module provided by the embodiments of the present disclosure can sense the change in its own temperature caused by power-on operation through the temperature sensor and collect the temperature of the dToF module in real time, and then generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor. This process does not require placing the dToF module in a temperature-changing device, which not only reduces the test cost but also saves a large amount of test time. Only by collecting the temperature of the dToF module and the first ranging result at different temperatures when the dToF module is working can a ranging temperature drift curve of the dToF module be generated, which has the advantages of low cost and short test time.

[0102] It should be understood that the "one embodiment" or "an embodiment" mentioned throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present disclosure. Therefore, the appearances of "in one embodiment" or "in an embodiment" throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in various embodiments of the present disclosure, the magnitudes of the serial numbers of the above processes do not mean the order of execution, and the order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present disclosure. The serial numbers of the embodiments of the present disclosure above are only for description and do not represent the advantages and disadvantages of the embodiments.

[0103] The above are only the preferred embodiments of the present disclosure, and do not limit the patent scope of the present disclosure. Any equivalent structural transformation made by using the content of the specification and drawings of the present disclosure under the inventive concept of the present disclosure, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present disclosure.

Claims

1. A dToF module, characterized in that, It includes a temperature sensor and a data processor; The temperature sensor is configured to collect the temperature of the dToF module when the dToF module is operating; The data processor is configured to obtain a first ranging result of the dToF module for a calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

2. The dToF module according to claim 1, wherein The data processor is further configured to obtain a second ranging result of the dToF module for a target object, and correct the second ranging result according to the temperature of the dToF module and the ranging temperature drift curve to obtain a first corrected result.

3. The dToF module according to claim 1, wherein, The dToF module further includes a time-to-digital converter; The temperature sensor is configured to obtain the temperature of the time-to-digital converter or / and the data processor when the dToF module is operating.

4. The dToF module according to claim 3, characterized in that, The data processor is further configured to: when obtaining the first ranging result, simultaneously obtain the number of valid delay units in the time-to-digital converter, and generate an accuracy temperature drift curve of the time-to-digital converter according to the first ranging result, the preset distance, the number of valid delay units, and the temperature collected by the temperature sensor.

5. The dToF module according to claim 4, wherein The data processor is further configured to: obtain the second ranging result of the dToF module for a target object, simultaneously obtain the number of valid delay units in the time-to-digital converter, correct the time-to-digital converter according to the accuracy temperature drift curve to obtain a corrected accuracy, and then correct the second ranging result according to the temperature collected by the temperature sensor, the number of valid delay units, and the corrected accuracy to obtain a second corrected result.

6. The dToF module according to claim 3, wherein, The distance between the temperature sensor and the time-to-digital converter or / and the data processor is less than a preset threshold.

7. The dToF module according to claim 3, characterized in that The time-to-digital converter includes a plurality of time-to-digital conversion units, and the temperature sensor includes a plurality of temperature sensing units; Wherein, each temperature sensing unit collects the temperature of at least one of the time-to-digital conversion units, and the distance between the temperature sensing unit and the corresponding time-to-digital conversion unit for which the temperature is collected is less than a preset threshold.

8. The dToF module according to claim 7, wherein The plurality of time-to-digital conversion units are arranged in an array in a preset plane, and the plurality of temperature sensing units are distributed on the periphery of the array of the time-to-digital conversion units.

9. The dToF module according to claim 7, wherein The data processor is configured to: when obtaining the first ranging result, simultaneously obtain the number of valid delay units in the time-to-digital conversion unit corresponding to the temperature collected by each temperature sensing unit, and generate an accuracy temperature drift curve of each time-to-digital conversion unit according to the first ranging result, the preset distance, the number of valid delay units, and the temperature collected by the temperature sensing unit.

10. A control method for a dToF module, characterized in that, The dToF module includes: a temperature sensor and a data processor; the control method includes: Controlling the temperature sensor to collect the temperature of the dToF module when the dToF module is operating; Control the data processor to obtain the first ranging result of the dToF module for a calibration object at a preset distance at different temperatures, and generate a ranging temperature drift curve of the dToF module according to the first ranging result, the preset distance, and the temperature collected by the temperature sensor.

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