CN110501691A - Noise filtering method of TOF module, TOF module and device - Google Patents

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 technology, and in particular, to a noise filtering method, TOF module and device for a Time Of Flight (TOF) module.

Background technique

The TOF module calculates the distance between the external shooting object and the camera by measuring the flight time of the emitted optical signal in space. Figure 1 shows the principle of TOF module ranging. The TOF module includes a transmitting unit, a receiving unit, a modulation unit, a demodulation unit and a processor. Among them, the modulation unit is responsible for modulating the emitted infrared light, and the infrared light is emitted through the transmitting unit; the receiving unit receives the reflected light reflected by the surface of the photographed object, and the demodulating unit is responsible for demodulating the reflected light received by the receiving unit; signal processing The module includes an analog-to-digital converter (Analog-to-Digital Converter, ADC) and a processor, the ADC is used to convert analog signals into digital signals, and the processor compares the transmitted light wave signal with the received reflected signal to obtain their The phase difference, according to the frequency of the signal, can know the time that the light wave passes through an emission-reflection path, so that the depth information corresponding to each pixel in the actual three-dimensional space can be obtained according to the speed of light.

Figure 2 shows a schematic diagram of the light propagation path of the TOF module ranging; the surface of the TOF module is protected by a glass cover, and the infrared light emitted by the transmitting unit passes through the glass cover and is projected on the surface of the object to be photographed in the external space. The receiving unit reflects the target reflected light (effective signal for ranging), and the target reflected light is received by the receiving unit. Since the cover plate is usually a transparent glass cover plate, the transmittance is generally above 90%, but there is still a certain reflectivity. , this part of the non-target reflected light received by the receiving unit after multiple reflections by the glass cover is a noise signal that affects the depth measurement, and this noise signal usually appears on the side of the receiving unit close to the transmitting unit, at this position Pixels will receive valid signals that are normally reflected and noise signals that are repeatedly reflected inside the glass cover. The existence of such noise signals will affect the accuracy and integrity of depth information measurement. This noise is called edge noise.

Figure 3 is a schematic diagram of a depth image with edge noise. This image is a depth map of a white wall taken at a distance of 1m. The left side of the image is the side of the receiving unit away from the transmitting unit, and the depth value value at the pixel point (x1, y1) =1000mm, high accuracy; the right side of the image is the side of the receiving unit close to the transmitting unit (that is, the side with edge noise), the depth value at the pixel point (x2, y2) value=1015mm, the accuracy is poor.

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

1) The glass cover plate is made into a separate type, that is, two glass cover plates are used, one covers the transmitting unit and the other covers the receiving end; in this way, the reflected light formed by the glass cover covering the transmitting unit will not be entered. receiving unit;

2) Increase the distance between the transmitting unit and the receiving unit, increase the number of reflections inside the glass cover, attenuate the reflected light, and eliminate or weaken the energy of the reflected light entering the receiving unit.

However, using the first method will affect the consistency of the appearance of the device, and the assembly of two cover plates is more complicated than that of one cover plate, requiring separate coating, and the cost is high; using the second method will affect the overall space setting of the device. It can be seen that a better solution is still required for the above technical problems.

SUMMARY OF THE INVENTION

In order to solve the above technical problems, the 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 solutions of the embodiments of the present application are implemented as follows:

A first aspect provides a noise filtering method for a TOF module, the TOF module includes: a transmitting unit and a receiving unit, the receiving unit includes a pixel array, and at least some pixels in the pixel array include a noise filtering unit, and the noise filtering The unit is used to filter out the noise signal in the receiving unit;

This method includes:

controlling the emission unit to emit outgoing light signals;

The receiving unit is controlled to receive the incident light signal; wherein, the incident light signal at least includes: the target incident light formed by the reflection of the target photographed object, and the non-target incident light that introduces a noise signal;

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

The noise signal in the electrical signal is filtered out based on the noise filtering unit to obtain the target electrical signal.

In a second aspect, a TOF module is provided, the TOF module includes: a transmitting unit and a receiving unit, the receiving unit includes a pixel array, at least some of the pixels in the pixel array include a noise filtering unit, and the noise filtering unit is used for filtering the noise signal in the receiving unit;

a transmitting unit for transmitting outgoing optical signals;

a receiving unit, configured to receive an incident light signal; wherein, the incident light signal at least includes: target incident light reflected by the target photographed object, and non-target incident light that introduces noise signals;

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

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

In a third aspect, a noise filtering device is provided, the device comprising: a TOF module, a processor, and a memory configured to store a computer program that can be executed on the processor; wherein,

The TOF module includes: a transmitting unit and a receiving unit, the receiving unit includes a pixel array, and at least some of the pixels in the pixel array include a noise filtering unit, and the noise filtering unit is used to filter out the noise signal in the receiving unit;

When the processor is configured to run a computer program, it is used to implement the following steps:

controlling the emission unit to emit outgoing light signals;

The receiving unit is controlled to receive the incident light signal; wherein, the incident light signal at least includes: the target incident light formed by the reflection of the target photographed object, and the non-target incident light that introduces a noise signal;

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

The noise signal in the electrical signal is filtered out based on the noise filtering unit to obtain the target electrical signal.

In a fourth aspect, there is provided a computer-readable storage medium 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 above technical solution, when the TOF module is used to take a depth image, the noise filtering unit can be used to effectively filter the noise signal converted from the non-target incident light signal in the electrical signal, and only the target electrical signal converted from the target incident light signal can be retained. , using the obtained effective target electrical signal to achieve depth measurement, which can improve the measurement accuracy and eliminate the influence of noise signals on the depth measurement.

Description of drawings

Figure 1 is a schematic diagram of the TOF module ranging principle;

Fig. 2 is the schematic diagram of the light propagation path of TOF module ranging;

3 is a schematic diagram of a depth image with edge noise;

4 is a schematic diagram of a window switch mode inside a pixel;

5 is a schematic diagram of a pixel window receiving stored charges;

6 is a schematic flowchart of a noise filtering method in an embodiment of the present application;

FIG. 7 is a schematic diagram of a composition structure of a pixel structure in an embodiment of the present application;

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

9 is a schematic diagram of a second window switching mode inside a pixel in an embodiment of the present application;

10 is a first schematic flowchart of a method for configuring a noise filtering unit in an embodiment of the present application;

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

12 is a second schematic flowchart of a method for configuring a noise filtering unit in an embodiment of the present application;

13 is a schematic diagram of a third window switching mode inside a pixel in an embodiment of the present application;

14 is a schematic diagram of the composition structure of the TOF module in the embodiment of the application;

FIG. 15 is a schematic diagram of the composition and structure of a noise filtering device in an embodiment of the present application.

Detailed ways

In order to have a more detailed understanding of the features and technical contents of the embodiments of the present application, the implementation of the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

A noise filtering method for a TOF module provided by an embodiment of the present application is based on the TOF ranging principle,

Figure 4 is a schematic diagram of a window switch mode inside a pixel. As shown in Figure 4, after the emission unit emits an outgoing light signal, the outgoing light signal is reflected by the target object to form reflected light and enters the receiving unit, and each pixel at the receiving end They are all composed of a photosensitive unit (such as a photodiode), which can convert incident light into electric charges. The photosensitive unit is connected with multiple high-frequency switching switches (G0 and G1 in Figure 4), which can introduce charges into different storage devices. The electric signals are read out from the readout port 0 and the readout port 1 respectively.

G0 and G1 are respectively turned on according to the switching sequence within a pulse time T, and last for a period of time t, the charges are accumulated as Q0 and Q1, and then the time interval Δt of laser signal emission and return is calculated as: Δt=[Q1/ (Q0+Q1)]·t.

The order in which G0 and G1 are turned on is:

When the transmitting unit is started to transmit the pulse signal, the G0 of each pixel is turned on, and after a pulse time t (the time for the laser to emit a pulse), G1 is turned on, and G0 is turned off at the same time;

During this time t, part of the signal reflected by the laser is received by G0 and converted into charge and stored in S0, and the rest of the signal is received by G1 and stored in S1;

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

The outgoing light pulse signal continues to emit light for a period of time t according to the set working mode, and the charge for time t is accumulated in S0 and S1 respectively. After a phase ends, the TOF sensor converts the charge into voltage and stores it in the register, then S0 and S1 can use the above formula Δt=[Q1/(Q0+Q1)]·t to obtain the time of laser emission and return, and then calculate the distance between the camera and the target object according to the formula d=(Δt·c)/2 The distance d, c is the speed of light.

An embodiment of the present application provides a noise filtering method for a TOF module, which can filter noise signals caused by non-target incident light. The TOF module includes: a transmitting unit and a receiving unit, and the receiving unit includes a pixel array , at least some of the pixels in the pixel array include a noise filtering unit, and the noise filtering unit is used to filter the noise signal in the receiving unit;

FIG. 6 is a schematic flowchart of a noise filtering method in an embodiment of the present application. As shown in FIG. 6 , the method may specifically include:

Step 101: control the emission unit to emit an outgoing optical signal;

Step 102 : controlling the receiving unit to receive an incident light signal; wherein the incident light signal at least includes: target incident light reflected by a target photographed object, and non-target incident light introduced into the noise signal;

Step 103: Control the receiving unit to convert the incident light signal into an electrical signal; wherein the electrical signal at least includes: a target electrical signal corresponding to the target incident light, and the non-target incident light corresponding to the target electrical signal. noise signal;

Step 104: Filter out the noise signal in the electrical signal based on the noise filtering unit to obtain the target electrical signal.

Here, the execution subject of steps 101 to 104 may be a processor of a device configured with a TOP camera module. For example, smartphones, personal computers (e.g. tablets, desktops, notebooks, netbooks, PDAs), mobile phones, e-book readers, portable multimedia players, audio/video players, cameras, virtual reality devices and wearables equipment, etc.

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

Wherein, the photoelectric conversion unit is used to receive the incident light signal and convert the incident light signal into charge output; the charge storage unit is used to store the output of the photoelectric conversion unit within a preset period of time. electric charge, output the accumulated electric charge to the electric charge conversion unit; the electric charge conversion unit is used for converting the input electric charge into a voltage signal.

In practical applications, the noise filtering unit can be located on the input side of the charge conversion unit or on the output side, and is used to filter the noise signal to obtain the target electrical signal. The target electrical signal is input to the ADC through the readout port. The ADC converts the target electrical signal into a digital signal.

Exemplarily, 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 applications, a light-transmitting cover plate is arranged above the transmitting unit and the receiving unit; the noise signal includes at least one of the following: a first noise caused by the reflected light of the light-transmitting cover plate entering the receiving unit signal, the second noise signal brought about by ambient light entering the receiving unit.

In practical applications, limited by the reflection angle of the light-transmitting cover plate, the first noise signal mostly affects the edge pixels in the pixel array close to the emission unit. Therefore, after determining the affected edge pixel area 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 ambient light is not limited by the angle of incidence, the second noise signal may affect all pixels. Therefore, it is necessary to configure a noise filtering unit for filtering the second noise signal inside each pixel.

That is to say, when the first noise signal and the second noise signal need to be filtered out at the same time, it is necessary to configure a noise filtering unit capable of filtering out the first noise signal and the second noise signal at the edge pixel area, and other areas can be configured to filter A noise filtering unit for removing the second noise signal.

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

Specifically, when the noise signal is a charge parameter, the electrical signal is the accumulated charge output by the charge storage unit, and the noise filtering unit is located on the side of the input end of the charge conversion unit; the use of the The noise filtering unit filters the noise signal in the electrical signal to obtain the target electrical signal, including: subtracting the noise signal from the electrical signal to obtain a target charge; using the charge conversion unit to convert The target charge is converted into the target electrical signal.

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

FIG. 8 is a schematic diagram of the switching mode of the first window inside the pixel in the embodiment of the present application; as shown in FIG. 8 , the signal filtering unit is a capacitor, and each pixel at the receiving end is composed of a photosensitive unit (such as a photodiode), which can The incident light is converted into electric charge, and the photosensitive unit is connected with two high-frequency switching switches G0 and G1. When the switch G0 is closed, the output charge of the photosensitive unit is introduced into the first circuit and stored in the capacitor S0. When the switch G1 is closed, the output charge of the photosensitive unit is introduced into the second circuit. road is stored in capacitor S1. A first noise filtering unit is configured after capacitor S0, and a second noise filtering unit is configured after S1 respectively. For calibration, the charge in the capacitor S0 is subtracted from the first noise filtering unit to obtain the target charge 0, and the charge in the capacitor S1 is subtracted from the second noise filtering unit to obtain the target charge 1, and the obtained signal is subjected to analog amplification, Then after ADC sampling, digital signal output can be performed, and subsequent digital signal processing can be performed.

Specifically, when the noise signal is a voltage parameter, the electrical signal is the voltage output by the charge conversion unit, and the noise filtering unit is located on the side of the output end of the charge conversion unit; the use of the noise filter The removing unit filters out the noise signal in the electrical signal to obtain the target electrical signal, including: subtracting the noise signal from the electrical signal to obtain the target electrical signal.

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

FIG. 9 is a schematic diagram of the switching mode of the second window inside the pixel in the embodiment of the present application; as shown in FIG. 9 , the signal filtering unit is a capacitor, and each pixel at the receiving end is composed of a photosensitive unit (such as a photodiode), which can The incident light is converted into electric charge, and the photosensitive unit is connected with two high-frequency switching switches G0 and G1. When the switch G0 is closed, the output charge of the photosensitive unit is introduced into the first circuit and stored in the capacitor S0. When the switch G1 is closed, the output charge of the photosensitive unit is introduced into the second circuit. road is stored in capacitor S1. Amplifier 0 and amplifier 1 are set after capacitor S0 and capacitor S1, respectively, to amplify the accumulated charge output by the capacitor and convert it into a voltage output. Based on this, the register of the amplifier is set, and the voltage of the corresponding noise signal is written. When the voltage is applied, the voltage of the noise signal is subtracted, so that the output voltage is only the voltage of the target incident light.

The noise signal includes the first noise signal caused by the reflected light of the transparent cover plate entering the receiving unit, and a method for configuring the noise filtering unit is further provided. FIG. 10 is a first schematic flowchart of a method for configuring a noise filtering unit in an embodiment of the present application. As shown in FIG. 10 , the method includes:

Step 201 : disposing a light shield on the outside of the first surface of the light-transmitting cover plate away from the transmitting unit and the receiving unit, and controlling the transmitting unit to emit an outgoing 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 the upper surface of the light-transmitting cover plate.

FIG. 11 is a schematic diagram of the principle of obtaining the first noise signal in the embodiment of the present application. 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 transmitting unit is incident on the glass cover plate, and then passes through the cover glass. The multiple reflections on the inner side of the upper surface and the inner side of the lower surface of the glass cover form the first incident light (ie, the reflected light of the glass cover), which is incident inside the receiving unit and received by the pixels in the receiving unit.

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

Step 203: Convert 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 output, the charge storage unit is controlled to store the charge output by the photoelectric conversion unit within a preset time period, and the accumulated charge is output 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 a charge output, the charge storage unit is controlled to store the charge output by the photoelectric conversion unit within a preset time period, the accumulated charge is output, and the charge is controlled The conversion unit converts the accumulated charge into a voltage, and the output voltage is the first noise signal.

Step 204: Based on the first noise signal, configure the noise filtering unit.

Specifically, when the first noise signal is a charge parameter, the noise filtering unit may be a capacitor, and the first noise signal is used to configure the capacitor parameter for filtering the first noise signal under normal shooting conditions. When the first noise signal is a voltage parameter, the noise filtering unit may be a register that stores the voltage corresponding to the noise signal, and after the charge is converted into a voltage, the voltage of the noise signal is obtained from the register, and the voltage of the noise signal is outputted when the voltage is output. Subtracted, so that the output voltage is only the voltage of the target incident light.

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

1) The transmitting unit and receiving unit of the TOF are covered with a glass cover, and the surface of the glass cover is pasted with black opaque paper, so that the TOF sensor cannot receive the effective target incident signal; at this time, the TOF sensor only After receiving the non-target incident signal brought by the internal reflection of the cover glass cover, after a phase time t, the accumulated charges of G0 and G1 are respectively recorded as Q00 and Q10;

2) use Q00 and Q10 to set the corresponding first noise filtering unit and the second noise filtering unit respectively;

3) Under normal circumstances, the surface of the glass change is not covered. At this time, the TOF sensor not only receives the target incident signal projected on the space photographed object, but also receives the first reflection signal brought by the reflection inside the glass cover; after the same After a phase time t, the charges accumulated by G0 and G1 are respectively recorded as Q01 and Q11;

4) Q01 and Q11 pass through the first noise filtering unit and the second noise filtering unit, respectively, to filter out the charges accumulated by reflection in the glass cover to obtain the target charges Q0 and Q1; 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 voltage, and the first noise signal is stored in the register. In this way, when the pixel voltage is read out, the voltage of the first noise signal is subtracted to obtain target voltage signal.

The noise signal includes a second noise signal brought about by ambient light entering the receiving unit, and a method for configuring the noise filtering unit is further provided. FIG. 12 is a second schematic flowchart of a method for configuring a noise filtering unit in an embodiment of the present application. As shown in FIG. 12 , the method includes:

Step 301: control the transmitting unit to turn off;

Step 302: control the receiving unit to receive external ambient light as the second incident light;

Here, the unit is turned off, and the receiving unit is turned on to receive the ambient light from the outside, and the second noise signal under different ambient brightness can be calibrated. For example, the current ambient brightness can be determined according to the RGB camera or light sensor, and the corresponding first Second noise signal, the second noise signal under different brightness is pre-calibrated to establish a noise filtering unit.

Step 303: Convert the second incident light into a second 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 output, the charge storage unit is controlled to store the charge output by the photoelectric conversion unit within a preset time period, and the accumulated charge is output 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 a charge output, the charge storage unit is controlled to store the charge output by the photoelectric conversion unit within a preset time period, the accumulated charge is output, and the charge is controlled The conversion unit converts the accumulated charge into a voltage, and the output voltage is the first noise signal.

Step 304: Based on the second noise signal, configure the noise filtering unit.

Specifically, when the first noise signal is a charge parameter, the noise filtering unit may be a capacitor, and the first noise signal is used to configure the capacitor parameter for filtering the first noise signal under normal shooting conditions. When the first noise signal is a voltage parameter, the noise filtering unit may be a register that stores the voltage corresponding to the noise signal, and after the charge is converted into a voltage, the voltage of the noise signal is obtained from the register, and the voltage of the noise signal is outputted when the voltage is output. Subtracted, so that the output voltage is only the voltage of the target incident light.

Since ambient brightness changes are relatively heavy, and ambient light is not limited by the incident angle, the second noise signal may affect all pixels. Therefore, it is necessary to configure a noise filtering unit for filtering the second noise signal inside each pixel.

By adopting the above technical solution, when the TOF module is used to take a depth image, the noise filtering unit can be used to effectively filter the noise signal converted from the non-target incident light signal in the electrical signal, and only the target electrical signal converted from the target incident light signal can be retained. , using the obtained effective target electrical signal to achieve depth measurement, which can improve the measurement accuracy and eliminate the influence of noise signals on the depth measurement.

13 is a schematic diagram of the switching mode of the third window inside the pixel in the embodiment of the present application to eliminate ambient light noise. On the basis of the current TOF sensors G0 and G1, a separate switch G2 is set up. The function of G2 is that after G0 and G1 are completed, When the transmitting unit is turned off, the output charge of the G2 closed photosensitive unit is introduced into the third channel and stored in the capacitor S2, and the voltage corresponding to the second noise signal is determined according to the charge stored in S2 within a phase time; during normal shooting, after a phase time is completed , when the voltage is read out, the voltage read out from S2 is subtracted, and the ambient light noise can be eliminated.

The embodiment of the present application also provides a TOF module, as shown in FIG. 14 , the TOF module includes: a transmitting unit 141 and a receiving unit 142 , the receiving unit includes a pixel array, at least part of the pixel array A noise filtering unit is included in the pixel, and the noise filtering unit is used to filter the noise signal in the receiving unit;

The transmitting unit 141 is used for transmitting outgoing optical signals;

The receiving unit 142 is configured to receive an incident light signal; wherein, the incident light signal at least includes: target incident light reflected by the target object, and non-target incident light introduced into the noise signal;

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

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

In some embodiments, the pixel further includes a photoelectric conversion unit, a charge storage unit and a charge conversion unit; wherein the photoelectric conversion unit is configured to receive the incident light signal and convert the incident light signal into charge output; the charge storage unit is used to store the charge output by the photoelectric conversion unit within a preset time period, and output the accumulated charge to the charge conversion unit; the charge conversion unit is used to convert the input charge into a voltage Signal.

In some embodiments, when the noise signal is a charge parameter, the electrical signal is the accumulated charge output by the charge storage unit, and the noise filtering unit is located on the 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; the charge conversion unit is used to convert the target charge into the target electrical signal.

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

In some embodiments, a light-transmitting cover plate is provided above the transmitting unit 141 and the receiving unit 142 ; the noise signal includes at least one of the following: the reflected light of the light-transmitting cover plate enters the receiving unit and brings about The first noise signal and the second noise signal brought about by ambient light entering the receiving unit.

In some embodiments, when the noise signal includes the first noise signal, the transmitting unit 141 is further configured to provide a light shield on the outside of the first surface of the light-transmitting cover plate away from the transmitting unit and the receiving unit a piece, which emits an outgoing light signal to the light-transmitting cover plate;

Correspondingly, the receiving unit 142 is further configured to receive the first incident light reflected by the transparent cover plate; convert the first incident light into a first noise signal; based on the first noise signal , configure the noise filtering unit.

In some embodiments, when the noise signal includes a second noise signal, the receiving unit 142 is further configured to receive ambient light as the second incident light when the transmitting unit is turned off; receive the second incident light The light is converted into a second noise signal; based on the second noise signal, the noise filtering unit is configured.

The embodiment of the present application further provides a noise filtering device, as shown in FIG. 15 , the device includes: a TOF module 151, a processor 152, and a memory 153 configured to store a computer program that can be run on the processor; in,

The TOF module 151 includes: a transmitting unit and a receiving unit, the receiving unit includes a pixel array, and at least some pixels in the pixel array include a noise filtering unit, and the noise filtering unit is used to filter out the receiving unit. noise signal within the cell;

When the processor 152 is configured to run the computer program, it is configured to implement the following steps:

controlling the emission unit to emit outgoing light signals;

Controlling the receiving unit to receive an incident light signal; wherein the incident light signal at least includes: target incident light reflected by the target photographed object, and non-target incident light introduced into the noise signal;

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

The target electrical signal is obtained by filtering the noise signal in the electrical signal based on the noise filtering unit.

In some embodiments, the pixel further includes a photoelectric conversion unit, a charge storage unit and a charge conversion unit; wherein the photoelectric conversion unit is configured to receive the incident light signal and convert the incident light signal into charge output; the charge storage unit is used to store the charge output by the photoelectric conversion unit within a preset time period, and output the accumulated charge to the charge conversion unit; the charge conversion unit is used to convert the input charge into a voltage Signal.

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

When the processor 152 is configured to run the computer program, it is specifically configured to implement the following steps: subtracting the noise signal from the electrical signal to obtain a target charge; converting the target charge by using the charge conversion unit for the target electrical signal.

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 the output end of the charge conversion unit;

When the processor 152 is configured to run the computer program, it is specifically configured to implement the following steps: subtract the noise signal from the electrical signal to obtain the target electrical signal.

In some embodiments, a light-transmitting cover plate is provided above the transmitting unit and the receiving unit; the noise signal includes at least one of the following: the first light caused by the reflected light of the light-transmitting cover plate entering the receiving unit A noise signal, the second noise signal brought about by ambient light entering the receiving unit.

In some embodiments, when the noise signal includes the first noise signal, when the processor 152 is configured to run the computer program, the processor 152 is further configured to implement the following step: when the light-transmitting cover plate is far away from the emitting unit A light-shielding member is arranged on the outside of the first surface of the receiving unit and the transmitting unit is controlled to emit an outgoing light signal to the light-transmitting cover plate; incident light; converting the first incident light into a first noise signal; and configuring the noise filtering unit based on the first noise signal.

In some embodiments, when the noise signal includes the second noise signal, when the processor 152 is configured to run the computer program, the processor 152 is further configured to implement the following steps: controlling the transmitting unit to turn off; controlling the receiving unit receiving ambient light as second incident light; converting the second incident light into a second noise signal; and configuring the noise filtering unit based on the second noise signal.

Of course, in practical application, as shown in FIG. 15 , various components in the noise filtering device are coupled together through a bus system 154 . It will be appreciated that the bus system 154 is used to implement connection communication between these components. In addition to the data bus, the bus system 154 also includes a power bus, a control bus, and a status signal bus. However, for the sake of clarity, the various buses are labeled as bus system 154 in FIG. 15 .

In practical applications, the above-mentioned processor may be an application specific integrated circuit (ASIC, Application Specific Integrated Circuit), a digital signal processing device (DSPD, Digital Signal Processing Device), a programmable logic device (PLD, Programmable Logic Device), a field programmable gate At least one of an array (Field-Programmable Gate Array, FPGA), a controller, a microcontroller, and a microprocessor. It can be understood that, for different devices, the electronic device used to implement the function of the above processor may also be other, which is not specifically limited in the embodiment of the present application.

The above-mentioned memory can be a volatile memory (volatile memory), such as a random access memory (RAM, Random-Access Memory); or a non-volatile memory (non-volatile memory), such as a read-only memory (ROM, Read-Only Memory) Memory), flash memory (flash memory), hard disk (HDD, Hard Disk Drive) or solid-state drive (SSD, Solid-State Drive); or a combination of the above types of memory, and provide instructions and data to the processor.

Embodiments of the present application further provide a computer-readable storage medium for storing a computer program.

Optionally, the computer-readable storage medium can be applied to any noise filtering apparatus in the embodiments of the present application, and the computer program enables the computer to execute the corresponding processes implemented by the processor in each method of the embodiments of the present application, For brevity, details are not repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus and method may be implemented in other manners. The device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined, or Can be integrated into another system, or some features can be ignored, or not implemented. In addition, the coupling, or direct coupling, or communication connection between the components shown or discussed may be through some interfaces, and the indirect coupling or communication connection of devices or units may be electrical, mechanical or other forms. of.

The unit described above as a separate component may or may not be physically separated, and the component displayed as a unit may or may not be a physical unit, that is, it may be located in one place or distributed to multiple network units; Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

In addition, each functional unit in each embodiment of the present invention may all be integrated into one processing module, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integration The unit can be implemented either in the form of hardware or in the form of hardware plus software functional units. Those of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by program instructions related to hardware, the aforementioned program can be stored in a computer-readable storage medium, and when the program is executed, execute It includes the steps of the above method embodiments; and the aforementioned storage medium includes: a removable storage device, an RO, a RAM, a magnetic disk or an optical disk and other media that can store program codes.

The methods disclosed in the several method embodiments provided in this application can be arbitrarily combined under the condition of no conflict to obtain new method embodiments.

The features disclosed in the several product embodiments provided in this application can be combined arbitrarily without conflict to obtain a new product embodiment.

The features disclosed in several method or device embodiments provided in this application can be combined arbitrarily without conflict to obtain new method embodiments or device embodiments.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

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;

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.

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;

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.

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

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.

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.