CN110501691B

CN110501691B - Noise filtering method of TOF module, TOF module and device

Info

Publication number: CN110501691B
Application number: CN201910745569.3A
Authority: CN
Inventors: 王路
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2019-08-13
Filing date: 2019-08-13
Publication date: 2022-03-08
Anticipated expiration: 2039-08-13
Also published as: CN110501691A

Abstract

The embodiment of the application discloses a noise filtering method of a TOF module, the TOF module and a device, wherein the method comprises the following steps: controlling the emission unit to emit an emitted light signal; controlling the receiving unit to receive an incident light signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object, and non-target incident light into which the noise signal is introduced; controlling the receiving unit to convert the incident optical signal into an electrical signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to the target incident light and the noise signal corresponding to the non-target incident light; and filtering the noise signal in the electric signal based on the noise filtering unit to obtain the target electric signal. Therefore, the depth measurement is realized by obtaining the effective target electric signal, the measurement precision can be improved, and the influence of the noise signal on the depth measurement is eliminated.

Description

Noise filtering method of TOF module, TOF module and device

Technical Field

The present application relates to electronic technologies, and in particular, to a method for filtering noise Of a Time Of Flight (TOF) module, a TOF module, and a device thereof.

Background

The TOF module calculates the distance between an external shooting object and the camera by measuring the flight time of the transmitted optical signal in the space. The TOF module ranging principle is shown in fig. 1, the TOF module comprising a transmitting unit, a receiving unit, a modulating unit, a demodulating unit and a processor. The modulation unit is responsible for modulating the emitted infrared light, and the infrared light is emitted out through the emission unit; the receiving unit receives reflected light reflected by the surface of the shot object, and the demodulation unit is responsible for demodulating the reflected light received by the receiving unit; the signal processing module comprises an Analog-to-Digital Converter (ADC) and a processor, wherein the ADC is used for converting an Analog signal into a Digital signal, the processor is used for comparing a transmitted light wave signal with a received reflection signal to obtain the phase difference of the transmitted light wave signal and the received reflection signal, the time of the light wave passing through a transmitting-reflecting path can be known according to the frequency of the signal, and therefore the depth information of each pixel point in the corresponding actual three-dimensional space can be obtained through calculation according to the light speed.

FIG. 2 shows a schematic diagram of ray propagation paths for TOF module ranging; the surface of the TOF module is protected by a glass cover plate, infrared light emitted by an emitting unit penetrates through the glass cover plate, the infrared light is projected to the surface of an external space shooting object and then reflects target reflected light (effective signal for ranging) to a receiving unit, the target reflected light is received by the receiving unit, the cover plate is usually a transparent glass cover plate, the transmittance is generally over 90 percent, but still has certain reflectivity, the part of the non-target reflected light which is reflected for multiple times by the glass cover plate and received by the receiving unit is a noise signal which influences depth measurement, the noise signal generally appears on one side of the receiving unit close to the emitting unit, a pixel at the position can receive the effective signal which is normally reflected and the noise signal which is reflected for multiple times by the inside of the glass cover plate, and the accuracy and integrity of the depth information measurement can be influenced by the existence of the noise signal, this noise is called edge noise.

Fig. 3 is a schematic diagram of a depth image with edge noise, where the depth image is a white wall depth image taken at 1m, the left side of the image is the side of the receiving unit far from the transmitting unit, and the depth value at the pixel point (x1, y1) is 1000mm, so that the accuracy is very high; the right side of the image is the side of the receiving unit close to the transmitting unit (i.e. the side with edge noise), and the depth value at the pixel point (x2, y2) is 1015mm, which is poor in accuracy.

To solve this problem, the solutions adopted in the prior art are as follows:

1) the glass cover plates are made into a split type, namely two glass cover plates are used, one covers the emission unit, and the other covers the receiving end; thus, the reflected light formed by the glass cover plate covering the transmitting unit is prevented from entering the receiving unit;

2) the distance between the transmitting unit and the receiving unit is increased, the number of reflection times inside the glass cover plate is increased, the reflected light is attenuated, and the energy of the reflected light entering the receiving unit is eliminated or weakened.

However, the first method affects the consistency of the appearance of the device, and the assembly of two cover plates is complicated relative to one cover plate, and the cost is high because the two cover plates need to be coated separately; the second method can affect the overall spatial arrangement of the device. It can be seen that a need still exists for a more optimal solution to the above-mentioned technical problem.

Disclosure of Invention

In order to solve the above technical problem, embodiments of the present application are expected to provide a noise filtering method for a TOF module, a TOF module and a device.

The technical scheme of the embodiment of the application is realized as follows:

in a first aspect, a noise filtering method for a TOF module is provided, where the TOF module includes: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

the method comprises the following steps:

controlling the emission unit to emit an emitted light signal;

controlling a receiving unit to receive an incident light signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object and non-target incident light into which a noise signal is introduced;

controlling the receiving unit to convert the incident light signal into an electric signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to target incident light and a noise signal corresponding to non-target incident light;

and filtering the noise signal in the electric signal based on the noise filtering unit to obtain a target electric signal.

In a second aspect, a TOF module is provided, the TOF module comprising: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

a transmitting unit for transmitting an emitted light signal;

a receiving unit for receiving an incident optical signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object and non-target incident light into which a noise signal is introduced;

the receiving unit is also used for converting the incident light signal into an electric signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to target incident light and a noise signal corresponding to non-target incident light;

and the receiving unit is also used for filtering the noise signals in the electrical signals by using the noise filtering unit to obtain the target electrical signals.

In a third aspect, a noise filtering apparatus is provided, the apparatus comprising: a TOF module, a processor and a memory configured to store a computer program executable on the processor; wherein the content of the first and second substances,

the TOF module includes: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

the processor, when configured to execute the computer program, is configured to perform the steps of:

controlling the emission unit to emit an emitted light signal;

In a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored, wherein the computer program, when executed by a processor, implements the steps of the aforementioned method.

By adopting the technical scheme, when the TOF module is used for shooting the depth image, the noise filtering unit can be used for effectively filtering the noise signal converted from the non-target incident light signal in the electric signal, only the target electric signal converted from the target incident light signal is reserved, the depth measurement is realized by obtaining the effective target electric signal, the measurement precision can be improved, and the influence of the noise signal on the depth measurement is eliminated.

Drawings

FIG. 1 is a schematic diagram of TOF module ranging principles;

FIG. 2 is a schematic diagram of the ray propagation path for TOF module ranging;

FIG. 3 is a schematic diagram of a depth image in the presence of edge noise;

FIG. 4 is a schematic view of a window switch mode within a pixel;

FIG. 5 is a schematic diagram of a pixel window receiving stored charge;

FIG. 6 is a flowchart illustrating a noise filtering method according to an embodiment of the present application;

FIG. 7 is a schematic structural diagram of a pixel structure according to an embodiment of the present disclosure;

FIG. 8 is a schematic diagram of a first window switch mode within a pixel in an embodiment of the present application;

FIG. 9 is a schematic diagram of a second window switch mode within a pixel in an embodiment of the present application;

FIG. 10 is a first flowchart illustrating a configuration method of a noise filtering unit according to an embodiment of the present invention;

FIG. 11 is a schematic diagram illustrating a first noise signal obtained in an embodiment of the present application;

FIG. 12 is a second flowchart illustrating a configuration method of a noise filtering unit according to an embodiment of the present invention;

FIG. 13 is a schematic diagram of a third window switch mode within a pixel according to an embodiment of the present application;

FIG. 14 is a schematic diagram of the structure of a TOF module according to an embodiment of the present disclosure;

fig. 15 is a schematic diagram of a component structure of a noise filtering apparatus in an embodiment of the present application.

Detailed Description

So that the manner in which the features and elements of the present embodiments can be understood in detail, a more particular description of the embodiments, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings.

The noise filtering method of the TOF module provided by the embodiment of the application is based on the TOF ranging principle,

fig. 4 is a schematic view of a window switch mode inside a pixel, as shown in fig. 4, after an emitting unit emits an outgoing light signal to the outside, the outgoing light signal is reflected by a target object to form a reflected light, and the reflected light is incident on a receiving unit, each pixel of a receiving end is composed of a photosensitive unit (e.g. a photodiode) which can convert the incident light into electric charges, the photosensitive unit is connected with a plurality of high frequency switches (e.g. G0 and G1 in fig. 4) which can introduce the electric charges into different capacitors (e.g. S0 and S1 in fig. 4) which can store the electric charges, and the electric signals are read from a read-out port 0 and a read-out port 1 respectively.

G0 and G1 turn on the pixel point according to the switching sequence in a pulse time T, lasting for a time T of one phase, the electric charge is accumulated into Q0 and Q1, and then the time interval delta T of laser signal emission and return is calculated as follows: Δ t ═ Q1/(Q0+ Q1) ] · t.

The sequence of G0 and G1 opening is:

g0 of each pixel is turned on when the emission unit is started to emit a pulse signal, G1 is turned on after the time t of one pulse (the time when the laser emits one pulse) is passed, and G0 is turned off;

during the time t, a part of the signal reflected by the laser is received by G0 and converted into charges to be stored in S0, and the rest of the signal is received by G1 and stored in S1;

fig. 5 is a schematic diagram of a pixel window receiving stored charges, and fig. 5 shows an outgoing light pulse signal emitted by an emission unit, a reflected light pulse signal, charges stored in a charge storage unit S0, and charges stored in a charge storage unit S1.

The emergent light pulse signal continuously emits light for a period of time of a phase t according to a set working mode, charges of the time t are respectively accumulated in S0 and S1, after one phase is finished, a TOF sensor converts the charges into voltages and stores the voltages in a register, then S0 and S1 obtain the time of laser emission and return by using the formula delta t ═ Q1/(Q0+ Q1) ] & t, then the distance d between a camera and a target object is calculated according to the formula d ═ delta t & c)/2, and c is the speed of light.

The embodiment of the application provides a noise filtering method of TOF module, can filter the noise signal that is brought by non-target incident light, the TOF module includes: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

fig. 6 is a schematic flow chart of a noise filtering method in an embodiment of the present application, and as shown in fig. 6, the method may specifically include:

step 101: controlling the emission unit to emit an emitted light signal;

step 102: controlling the receiving unit to receive an incident light signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object, and non-target incident light into which the noise signal is introduced;

step 103: controlling the receiving unit to convert the incident optical signal into an electrical signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to the target incident light and the noise signal corresponding to the non-target incident light;

step 104: and filtering the noise signal in the electric signal based on the noise filtering unit to obtain the target electric signal.

Here, the execution subject of steps 101 to 104 may be a processor of an apparatus configuring the TOP camera module. Such as smart phones, personal computers (e.g., tablet, desktop, notebook, netbook, palmtop), mobile phones, electronic book readers, portable multimedia players, audio/video players, cameras, virtual reality devices, wearable devices, and the like.

Fig. 7 is a schematic structural diagram of a pixel structure in an embodiment of the present application, where the pixel structure further includes a photoelectric conversion unit, a charge storage unit, and a charge conversion unit;

the photoelectric conversion unit is used for receiving the incident light signal and converting the incident light signal into charge to be output; the charge storage unit is used for storing the charges output by the photoelectric conversion unit in a preset time period and outputting accumulated charges to the charge conversion unit; the charge conversion unit is used for converting input charges into voltage signals.

In practical application, the noise filtering unit may be located at one side of the input end of the charge conversion unit, or at one side of the output end, and is configured to filter a noise signal to obtain a target electrical signal, where the target electrical signal is input to the ADC through the read port, and the ADC converts the target electrical signal into a digital signal.

Illustratively, the photoelectric conversion unit is a photodiode, the charge storage unit is a capacitor, and the charge conversion unit is a charge amplifier.

In practical application, light-transmitting cover plates are arranged above the transmitting unit and the receiving unit; the noise signal comprises at least one of: the reflected light of the light-transmitting cover plate enters a first noise signal brought by the receiving unit, and the ambient light enters a second noise signal brought by the receiving unit.

In practical application, the first noise signal mostly affects edge pixels close to the emission unit in the pixel array due to the limitation of the reflection angle of the light-transmitting cover plate. Therefore, after the affected edge pixel area is determined in advance, the noise filtering unit for filtering the first noise signal is configured only in the affected edge pixel area, and is not configured in the unaffected pixel area.

Since the ambient light is not limited by the angle of incidence, the second noise signal may affect all pixels. Therefore, a noise filtering unit for filtering the second noise signal needs to be disposed inside each pixel.

That is to say, when the first noise signal and the second noise signal need to be filtered simultaneously, a noise filtering unit capable of filtering the first noise signal and the second noise signal simultaneously needs to be configured in the edge pixel region, and a noise filtering unit capable of filtering the second noise signal needs to be configured in other regions.

In some embodiments, the noise filtering unit is located at the input end side or the output end side of the charge conversion unit.

Specifically, when the noise signal is a charge parameter, the electrical signal is an accumulated charge output by the charge storage unit, and the noise filtering unit is located at one side of the input end of the charge conversion unit; the filtering, by the noise filtering unit, the noise signal in the electrical signal to obtain the target electrical signal includes: subtracting the noise signal from the electrical signal to obtain a target charge; converting the target electric charge into the target electric signal with the charge conversion unit.

Here, the electric signal is also a charge parameter, and the target electric signal is a voltage signal. That is, before the charge signal is converted into the voltage signal, the charge converted from the non-target incident light is removed from the accumulated charge output from the charge storage unit to obtain the target charge, and the charge conversion unit converts the target charge to directly obtain the target voltage signal. Illustratively, the noise filtering unit may be a capacitor, and the capacitance of the capacitor is a charge corresponding to the noise signal.

FIG. 8 is a schematic diagram of a first window switch mode within a pixel in an embodiment of the present application; as shown in fig. 8, the signal filtering unit is a capacitor, each pixel at the receiving end is composed of a light sensing unit (e.g., a photodiode) which can convert incident light into electric charges, the light sensing unit is connected to two high frequency switches G0 and G1, when the switch G0 is closed, the electric charges output by the light sensing unit are led into the first path and stored in the capacitor S0, and when the switch G1 is closed, the electric charges output by the light sensing unit are led into the second path and stored in the capacitor S1. A first noise filtering unit is arranged behind the capacitor S0, a second noise filtering unit is arranged behind the capacitor S1, the electric charge amount of the first noise filtering unit and the electric charge amount of the second noise filtering unit are calibrated in advance according to reflected light of the light-transmitting cover plate, the first noise filtering unit is subtracted from the electric charge amount in the capacitor S0 to obtain a target electric charge 0, the second noise filtering unit is subtracted from the electric charge amount in the capacitor S1 to obtain a target electric charge 1, the obtained signal is subjected to analog amplification and then subjected to ADC (analog to digital converter) sampling, and then digital signal output can be carried out, and subsequent digital signal processing can be carried out.

Specifically, when the noise signal is a voltage parameter, the electrical signal is a voltage output by the charge conversion unit, and the noise filtering unit is located at one side of an output end of the charge conversion unit; the filtering, by the noise filtering unit, the noise signal in the electrical signal to obtain the target electrical signal includes: and subtracting the noise signal from the electric signal to obtain the target electric signal.

Here, the electric signal is also a voltage parameter, and the target electric signal is a voltage signal. That is, after the charge signal is converted into a voltage signal, a voltage converted from non-target incident light is subtracted from the output voltage signal, resulting in a target voltage signal. Illustratively, the noise filtering unit may be a register that stores a voltage corresponding to the noise signal.

FIG. 9 is a schematic diagram of a second window switch mode within a pixel in an embodiment of the present application; as shown in fig. 9, the signal filtering unit is a capacitor, each pixel at the receiving end is composed of a light sensing unit (e.g., a photodiode) which can convert incident light into electric charges, the light sensing unit is connected to two high frequency switches G0 and G1, when the switch G0 is closed, the electric charges output by the light sensing unit are led into the first path and stored in the capacitor S0, and when the switch G1 is closed, the electric charges output by the light sensing unit are led into the second path and stored in the capacitor S1. An amplifier 0 and an amplifier 1 are respectively arranged after the capacitor S0 and the capacitor S1, and are used for converting accumulated charges output by the capacitors into voltage output through amplification, based on which, a register of the amplifier is arranged, and corresponding voltages of noise signals are written, and the voltages of the noise signals are subtracted when the voltages are output, so that the output voltages are only the voltages of target incident light.

The noise signal comprises a first noise signal caused by reflected light of the light-transmitting cover plate entering the receiving unit, and a method for configuring the noise filtering unit is further provided. Fig. 10 is a first flowchart of a configuration method of a noise filtering unit in the embodiment of the present application, and as shown in fig. 10, the method includes:

step 201: arranging a shading piece on the outer side of a first surface of the light-transmitting cover plate, which is far away from the transmitting unit and the receiving unit, and controlling the transmitting unit to transmit an emergent light signal to the light-transmitting cover plate;

here, the light-transmitting cover plate may be a transparent glass cover plate or a transparent plastic cover plate, the light-shielding member may be opaque black paper, and the first surface is an upper surface of the light-transmitting cover plate.

Fig. 11 is a schematic diagram illustrating the principle of acquiring the first noise signal in the embodiment of the present application, and as shown in fig. 11, after the upper surface of the glass cover plate is covered by the light shielding member, the laser signal emitted by the emitting unit enters the glass cover plate, and is reflected multiple times by the inner sides of the upper surface and the lower surface of the glass cover plate to form first incident light (i.e., reflected light of the glass cover plate), and the first incident light enters the receiving unit and is received by the pixels in the receiving unit.

Step 202: controlling the receiving unit to receive first incident light formed by reflection of the light-transmitting cover plate;

step 203: converting the first incident light into a first noise signal;

specifically, when the first noise signal is a charge parameter, the photoelectric conversion unit is controlled to convert the first incident light signal into a charge and output the charge, the charge storage unit is controlled to store the charge output by the photoelectric conversion unit within a preset time period, and the output accumulated charge is the first noise signal.

When the first noise signal is a voltage parameter, the photoelectric conversion unit is controlled to convert the first incident light signal into electric charge to be output, the electric charge storage unit is controlled to store the electric charge output by the photoelectric conversion unit within a preset time period, accumulated electric charge is output, the electric charge conversion unit is controlled to convert the accumulated electric charge into voltage, and the output voltage is the first noise signal.

Step 204: configuring the noise filtering unit based on the first noise signal.

Specifically, when the first noise signal is a charge parameter, the noise filtering unit may be a capacitor, and the capacitor parameter is configured by using the first noise signal, so as to filter the first noise signal under a normal shooting condition. When the first noise signal is a voltage parameter, the noise filtering unit may be a register storing a voltage corresponding to the noise signal, and after the charge is converted into the voltage, the voltage of the noise signal is obtained from the register, and the voltage of the noise signal is subtracted when the voltage is output, so that the output voltage is only the voltage of the target incident light.

Here, the noise signal includes a first noise signal caused by the reflected light of the light-transmitting cover plate entering the receiving unit, and a complete implementation is given as follows:

1) a glass cover plate is covered on an emitting unit and a receiving unit of the TOF, and the upper surface of the glass cover plate is stuck by black lightproof paper, so that an effective target incident signal cannot be received by the TOF sensor; at the moment, the TOF sensor only receives a non-target incident signal brought by internal reflection of the cover glass cover plate, and after a phase time t, the charges accumulated by G0 and G1 are respectively marked as Q00 and Q10;

2) respectively arranging a corresponding first noise filtering unit and a corresponding second noise filtering unit by using Q00 and Q10;

3) normally, the changed surface of the glass is uncovered, and at the moment, the TOF sensor receives a target incident signal reflected by a shooting object projected to the space and also receives a first reflected signal brought by internal reflection of the glass cover plate; after the same phase time t, the charges accumulated by G0 and G1 are respectively marked as Q01Q 11;

4) the Q01 and the Q11 pass through the first noise filtering unit and the second noise filtering unit respectively, so that the charges accumulated by internal reflection of the glass cover plate can be filtered, and target charges Q0 and Q1 are obtained; Q0-Q01-Q00, Q1-Q11-Q10.

When the first noise signal is a voltage parameter, the noise filtering unit may be a register for storing a voltage, and the first noise signal is stored in the register, so that when the pixel voltage is read out, the voltage of the first noise signal is subtracted to obtain a target voltage signal.

The noise signal comprises a second noise signal resulting from ambient light entering the receiving unit, and a method of configuring a noise filtering unit is further provided. Fig. 12 is a second flowchart of a configuration method of a noise filtering unit in the embodiment of the present application, and as shown in fig. 12, the method includes:

step 301: controlling the transmitting unit to be closed;

step 302: controlling the receiving unit to receive external environment light as second incident light;

here, the closing unit turns on the receiving unit to receive the external ambient light, and may calibrate the second noise signals under different ambient brightness, for example, the current ambient brightness may be determined according to the RGB camera or the light sensor, the second noise signals corresponding to different ambient brightness may be obtained, and the second noise signals under different brightness may be calibrated in advance to establish the noise filtering unit.

Step 303: converting the second incident light into a second noise signal;

Step 304: configuring the noise filtering unit based on the second noise signal.

Since the ambient brightness variation is more loaded and the ambient light has no limitation of the incident angle, the second noise signal may affect all the pixels. Therefore, a noise filtering unit for filtering the second noise signal needs to be disposed inside each pixel.

Fig. 13 is a schematic diagram of a third window switching mode inside a pixel in the embodiment of the present application, in order to eliminate ambient light noise, on the basis of the current TOF sensors G0 and G1, a separate switch G2 is provided, and G2 has the effect that when the emission unit is turned off after G0 and G1 are completed, G2 closes the photosensitive unit to introduce the output charge of the photosensitive unit into a third path, where the charge is stored in a capacitor S2, and a voltage corresponding to a second noise signal is determined according to the charge stored in S2 in one phase time; in normal shooting, after one phase time is completed, the voltage read out from S2 is subtracted when reading out the voltage, so that the ambient light noise can be eliminated.

The embodiment of the present application further provides a TOF module, as shown in fig. 14, the TOF module includes: the receiving unit includes a pixel array, at least some pixels in the pixel array include a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

the transmitting unit 141 is used for transmitting an optical signal;

the receiving unit 142 is configured to receive an incident optical signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object, and non-target incident light into which the noise signal is introduced;

the receiving unit 142, further configured to convert the incident optical signal into an electrical signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to the target incident light and the noise signal corresponding to the non-target incident light;

the receiving unit 142 is further configured to filter the noise signal in the electrical signal by using the noise filtering unit, so as to obtain the target electrical signal.

In some embodiments, a photoelectric conversion unit, a charge storage unit and a charge conversion unit are further included in the pixel; the photoelectric conversion unit is used for receiving the incident light signal and converting the incident light signal into charge to be output; the charge storage unit is used for storing the charges output by the photoelectric conversion unit in a preset time period and outputting accumulated charges to the charge conversion unit; the charge conversion unit is used for converting input charges into voltage signals.

In some embodiments, when the noise signal is a charge parameter, the electrical signal is an accumulated charge output by the charge storage unit, and the noise filtering unit is located on one side of the input end of the charge conversion unit;

the receiving unit 142 is specifically configured to subtract the noise signal from the electrical signal to obtain a target charge; converting the target electric charge into the target electric signal with the charge conversion unit.

In some embodiments, when the noise signal is a voltage parameter, the electrical signal is a voltage output by the charge conversion unit, and the noise filtering unit is located at one side of an output end of the charge conversion unit; the receiving unit is specifically configured to subtract the noise signal from the electrical signal to obtain the target electrical signal.

In some embodiments, a transparent cover plate is disposed above the transmitting unit 141 and the receiving unit 142; the noise signal comprises at least one of: the reflected light of the light-transmitting cover plate enters a first noise signal brought by the receiving unit, and the ambient light enters a second noise signal brought by the receiving unit.

In some embodiments, when the noise signal includes a first noise signal, the transmitting unit 141 is further configured to dispose a light shielding member outside a first surface of the transparent cover plate away from the transmitting unit and the receiving unit, and transmit an outgoing light signal to the transparent cover plate;

correspondingly, the receiving unit 142 is further configured to receive a first incident light formed by reflection of the light-transmitting cover plate; converting the first incident light into a first noise signal; configuring the noise filtering unit based on the first noise signal.

In some embodiments, when the noise signal comprises a second noise signal, the receiving unit 142 is further configured to receive the second noise signal when the transmitting unit is turned off; receiving external environment light as second incident light; converting the second incident light into a second noise signal; configuring the noise filtering unit based on the second noise signal.

An embodiment of the present application further provides a noise filtering apparatus, as shown in fig. 15, the apparatus includes: a TOF module 151, a processor 152, and a memory 153 configured to store a computer program capable of running on the processor; wherein the content of the first and second substances,

the TOF module 151 includes: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

the processor 152 is configured to, when running the computer program, perform the following steps:

controlling the emission unit to emit an emitted light signal;

controlling the receiving unit to receive an incident light signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object, and non-target incident light into which the noise signal is introduced;

controlling the receiving unit to convert the incident optical signal into an electrical signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to the target incident light and the noise signal corresponding to the non-target incident light;

and filtering the noise signal in the electric signal based on the noise filtering unit to obtain the target electric signal.

the processor 152 is configured to, when running the computer program, specifically implement the following steps: subtracting the noise signal from the electrical signal to obtain a target charge; converting the target electric charge into the target electric signal with the charge conversion unit.

In some embodiments, when the noise signal is a voltage parameter, the electrical signal is a voltage output by the charge conversion unit, and the noise filtering unit is located at one side of an output end of the charge conversion unit;

the processor 152 is configured to, when running the computer program, specifically implement the following steps: and subtracting the noise signal from the electric signal to obtain the target electric signal.

In some embodiments, a light-transmitting cover plate is arranged above the transmitting unit and the receiving unit; the noise signal comprises at least one of: the reflected light of the light-transmitting cover plate enters a first noise signal brought by the receiving unit, and the ambient light enters a second noise signal brought by the receiving unit.

In some embodiments, when the noise signal comprises a first noise signal, the processor 152 is configured to execute the computer program to further implement the following steps: arranging a shading piece on the outer side of a first surface of the light-transmitting cover plate, which is far away from the transmitting unit and the receiving unit, and controlling the transmitting unit to transmit an emergent light signal to the light-transmitting cover plate; controlling the receiving unit to receive first incident light formed by reflection of the light-transmitting cover plate; converting the first incident light into a first noise signal; configuring the noise filtering unit based on the first noise signal.

In some embodiments, when the noise signal comprises a second noise signal, the processor 152 is configured to execute the computer program to further implement the following steps: controlling the transmitting unit to be closed; controlling the receiving unit to receive external environment light as second incident light; converting the second incident light into a second noise signal; configuring the noise filtering unit based on the second noise signal.

In practice, of course, the various components of the noise filtering device are coupled together by a bus system 154, as shown in fig. 15. It will be appreciated that the bus system 154 is used to enable communications among the components. The bus system 154 includes a power bus, a control bus, and a status signal bus in addition to a data bus. For clarity of illustration, however, the various buses are labeled as bus system 154 in fig. 15.

In practical applications, the processor may be at least one of an Application Specific Integrated Circuit (ASIC), a Digital Signal Processing Device (DSPD), a Programmable Logic Device (PLD), a Field Programmable Gate Array (FPGA), a controller, a microcontroller, and a microprocessor. It is understood that the electronic devices for implementing the above processor functions may be other devices, and the embodiments of the present application are not limited in particular.

The Memory may be a volatile Memory (volatile Memory), such as a Random-Access Memory (RAM); or a non-volatile Memory (non-volatile Memory), such as a Read-Only Memory (ROM), a flash Memory (flash Memory), a Hard Disk (HDD), or a Solid-State Drive (SSD); or a combination of the above types of memories and provides instructions and data to the processor.

The embodiment of the application also provides a computer readable storage medium for storing the computer program.

Optionally, the computer-readable storage medium may be applied to any noise filtering device in the embodiments of the present application, and the computer program enables a computer to execute corresponding processes implemented by a processor in each method in the embodiments of the present application, which is not described herein again for brevity.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. The above-described device embodiments are merely illustrative, for example, the division of the unit is only a logical functional division, and there may be other division ways in actual implementation, such as: multiple units or components may be combined, or may be integrated into another system, or some features may be omitted, or not implemented. In addition, the coupling, direct coupling or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection between the devices or units may be electrical, mechanical or other forms.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on a plurality of network units; some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, all the functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may be separately used as one unit, or two or more units may be integrated into one unit; the integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit. Those of ordinary skill in the art will understand that: all or part of the steps for implementing the method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer readable storage medium, and when executed, the program performs the steps including the method embodiments; and the aforementioned storage medium includes: a removable storage device, RO, RAM, a magnetic or optical disk, or the like.

The methods disclosed in the several method embodiments provided in the present application may be combined arbitrarily without conflict to obtain new method embodiments.

Features disclosed in several of the product embodiments provided in the present application may be combined in any combination to yield new product embodiments without conflict.

The features disclosed in the several method or apparatus embodiments provided in the present application may be combined arbitrarily, without conflict, to arrive at new method embodiments or apparatus embodiments.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims

1. A method of noise filtering a TOF module, the TOF module comprising: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

the method comprises the following steps:

controlling the emission unit to emit an emitted light signal;

2. The method according to claim 1, wherein the pixel further comprises a photoelectric conversion unit, a charge storage unit and a charge conversion unit;

the photoelectric conversion unit is used for receiving the incident light signal and converting the incident light signal into charge to be output;

the charge storage unit is used for storing the charges output by the photoelectric conversion unit in a preset time period and outputting accumulated charges to the charge conversion unit;

the charge conversion unit is used for converting input charges into voltage signals.

3. The method according to claim 2, wherein when the noise signal is a charge parameter, the electrical signal is an accumulated charge output by the charge storage unit, and the noise filtering unit is located at one side of an input end of the charge conversion unit;

the filtering, by the noise filtering unit, the noise signal in the electrical signal to obtain the target electrical signal includes:

subtracting the noise signal from the electrical signal to obtain a target charge;

converting the target electric charge into the target electric signal with the charge conversion unit.

4. The method according to claim 2, wherein when the noise signal is a voltage parameter, the electrical signal is a voltage output by the charge conversion unit, and the noise filtering unit is located at one side of an output end of the charge conversion unit;

and subtracting the noise signal from the electric signal to obtain the target electric signal.

5. The method according to any one of claims 1 to 4, wherein a light-transmitting cover plate is provided above the transmitting unit and the receiving unit;

the noise signal comprises at least one of: the reflected light of the light-transmitting cover plate enters a first noise signal brought by the receiving unit, and the ambient light enters a second noise signal brought by the receiving unit.

6. The method of claim 5, wherein when the noise signal comprises a first noise signal, the method further comprises:

arranging a shading piece on the outer side of a first surface of the light-transmitting cover plate, which is far away from the transmitting unit and the receiving unit, and controlling the transmitting unit to transmit an emergent light signal to the light-transmitting cover plate;

controlling the receiving unit to receive first incident light formed by reflection of the light-transmitting cover plate;

converting the first incident light into a first noise signal;

configuring the noise filtering unit based on the first noise signal.

7. The method of claim 5, wherein when the noise signal comprises a second noise signal, the method further comprises:

controlling the transmitting unit to be closed;

controlling the receiving unit to receive external environment light as second incident light;

converting the second incident light into a second noise signal;

configuring the noise filtering unit based on the second noise signal.

8. A TOF module, the TOF module comprising: the receiving unit comprises a pixel array, at least part of pixels in the pixel array comprise a noise filtering unit, and the noise filtering unit is used for filtering noise signals in the receiving unit;

the transmitting unit is used for transmitting an optical signal;

the receiving unit is used for receiving an incident light signal; wherein the incident optical signal comprises at least: target incident light formed by reflection of a target photographic object, and non-target incident light into which the noise signal is introduced;

the receiving unit is further used for converting the incident optical signal into an electric signal; wherein the electrical signal comprises at least: a target electrical signal corresponding to the target incident light and the noise signal corresponding to the non-target incident light;

the receiving unit is further configured to filter the noise signal in the electrical signal by using the noise filtering unit to obtain the target electrical signal.

9. A noise filtering device, the device comprising: a TOF module, a processor, and a memory configured to store a computer program executable on the processor; wherein the content of the first and second substances,

the processor is configured to, when running the computer program, perform the steps of:

controlling the emission unit to emit an emitted light signal;

10. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method of any one of claims 1 to 7.