CN218528641U - TOF module and sweeping robot - Google Patents

Abstract

The application provides a TOF module and robot of sweeping floor. The TOF module comprises a shell, a light source and a light modulation device; the light source and the light modulation device are arranged in the shell and are mutually spaced, and the light modulation device is positioned on a light path of the light source; the light source is used for emitting incident light beams; the light modulation device is used for modulating the incident light beams to project to a target area to form a corresponding emergent light field, and the near-ground illumination of the emergent light field is smaller than the far-ground illumination; the near-ground illumination is the illumination of the light field emitted from the target area at the near-ground position, and the far-ground illumination is the illumination of the light field emitted from the target area at the far-ground position. The application has reduced the higher near ground region of light intensity among the traditional TOF module and has caused the measurement accuracy of the lower far ground region of light intensity for the measurement accuracy of TOF module can be promoted effectively.

Description

TOF module and sweeping robot

[ technical field ] A

The application relates to optical ranging technical field, especially relates to a TOF module and robot of sweeping floor.

[ background ] A method for producing a semiconductor device

Although the TOF module in the sweeping robot has higher cost performance, the TOF module has some disadvantages, and analysis is performed on the principle of the TOF technology, so that the measurement accuracy of the TOF module in optical ranging and the light field distribution projected by the emitting end of the TOF module have a very close relationship, and the TOF module mainly relates to two characteristic indexes of light power and light field distribution uniformity.

In the related art, for the optical power, the factors influencing the measurement accuracy of the TOF module mainly include a system error and a random error, and the system error can be eliminated by means of calibration and the like, and the influence of the random error on the measurement accuracy of the TOF module is reduced by a mode of improving the optical power of the transmitting end of the TOF module. For the uniformity of light field distribution, light received by a single pixel in the TOF module receiving end sensor is not only a corresponding object point in the imaging relationship, but also stray light reflected by other object points, so that when the light field projected by the TOF module transmitting end is uniform, the single pixel in the TOF module receiving end sensor is less affected by the stray light; when the light field projected by the TOF module transmitting end is non-uniform, a single pixel in the TOF module receiving end sensor is greatly influenced by stray light, or in other words, the reflected light field is non-uniform and greatly influences the TOF module receiving end sensor, for example, a region with high reflected light intensity can generate relatively serious influence on a region with low reflected light, and a pixel overexposure can be caused when the reflected light intensity is high, so that a measurement error is generated.

And in being applied to the robot of sweeping the floor with the TOF module, because the TOF module need survey scene in a relatively large range, so the angle of field of view of TOF module transmitting terminal and receiving terminal is all great, because the work scene of robot of sweeping the floor is on the near-ground again, so the light field that TOF module transmitting terminal throws is very high after the ground reflection back light intensity, and far-ground regional reflection light intensity is lower, leads to near-ground regional department pixel overexposure for near-ground regional measurement error appears, can produce very serious influence to the measurement accuracy of other far-ground regions that light intensity is lower simultaneously.

Therefore, there is a need for an improved structure of the TOF module.

[ Utility model ] A method for manufacturing a semiconductor device

The application provides a TOF module and robot of sweeping floor aims at solving among the correlation technique because of the regional luminous intensity of nearly ground too high and leads to the lower problem of measurement accuracy of TOF module.

In order to solve the above technical problem, a first aspect of the embodiments of the present application provides a TOF module, including a housing, a light source, and a light modulation device; the light source and the light modulation device are arranged in the shell, the light source and the light modulation device are spaced from each other, and the light modulation device is positioned on a light path of the light source; the light source is used for emitting incident light beams; the light modulation device is used for modulating the incident light beams to project to a target area to form a corresponding emergent light field, and the near-ground illumination of the emergent light field is smaller than the far-ground illumination; the near-ground illumination is the illumination of the emergent light field at a near-ground position of the target area, and the far-ground illumination is the illumination of the emergent light field at a far-ground position of the target area.

The second aspect of the embodiment of the present application provides a robot of sweeping floor, including the TOF module of the first aspect of the embodiment of the present application.

As can be seen from the above description, the present application has the following advantages compared with the related art:

the light source emits an incident beam towards the light modulation device, then the light modulation device modulates the incident beam and projects the modulated incident beam to a target area to form a corresponding emergent light field, so that the near-ground illumination of the projected emergent light field is smaller than the far-ground illumination; the near-ground illumination is the illumination of the emergent light field at the near-ground position of the target area, and the far-ground illumination is the illumination of the emergent light field at the far-ground position of the target area. It can be seen from this that, the near ground illuminance of outgoing light field is less than far ground illuminance in this application, this application just explains that this application can reduce the illuminance of outgoing light field in the near ground position of target area compared with traditional technique to increase or do not change the illuminance of outgoing light field in the far ground position of target area, thereby reduced the higher near ground region of light intensity among the traditional TOF module and caused the measuring accuracy in the far ground region that light intensity is lower, make the measuring accuracy of TOF module can obtain promoting effectively.

[ description of the drawings ]

In order to more clearly illustrate the technical solutions in the related art or the embodiments of the present application, the drawings used in the description of the related art or the embodiments of the present application will be briefly described below, and it is obvious that the drawings in the description below are only some embodiments of the present application, but not all embodiments, and that other drawings may be obtained by those skilled in the art without creative efforts.

Fig. 1 is a light path diagram of a sweeping robot during optical ranging;

FIG. 2 is a schematic diagram of a first structure of a TOF module according to an embodiment of the present application;

FIG. 3 (1) is a graph of angle-illuminance on a target area before an optical axis is deflected according to an embodiment of the present application;

FIG. 3 (2) is a graph of angle-illuminance on a target area after deflecting an optical axis according to an embodiment of the present application;

fig. 4 (1) is a graph of an angle-illuminance relationship on a target region before asymmetric light field modulation provided in the embodiment of the present application;

fig. 4 (2) is an angle-illuminance relationship diagram on the target area after the asymmetric light field modulation provided in the embodiment of the present application;

fig. 5 is a second schematic structural diagram of a TOF module according to an embodiment of the application;

fig. 6 is a schematic diagram of a third structure of a TOF module according to an embodiment of the present disclosure.

[ detailed description ] embodiments

In order to make the objects, technical solutions and advantages of the present application more apparent and understandable, the present application will be clearly and completely described below in conjunction with embodiments of the present application and corresponding drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. It should be understood that the embodiments of the present application described below are only used for explaining the present application and are not used for limiting the present application, that is, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts based on the embodiments of the present application belong to the protection scope of the present application. In addition, the technical features involved in the embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

With the continuous improvement of the material and living standard of people and the rapid and violent development of robot technology, the sweeping robot is more and more popular in the household scene of people. The 3D (3-Dimension, three-dimensional) sensing technology carried by the existing sweeping robot can be a lot of flowers, such as a laser radar technology, a binocular technology, a structured light technology, a Time of Flight (TOF) technology and the like, wherein the TOF technology is particularly used (since the TOF technology has higher cost performance, the TOF technology is favored by manufacturers of various large sweeping robots), and the TOF module is mainly embodied in the sweeping robot. TOF technology, which is the most widely used 3D sensing technology at present, can be generally classified into two types, i.e., i-TOF (indirect-TOF) technology and D-TOF (direct-TOF) technology. The working principle of the TOF technique is: the laser source emits modulated (such as pulse modulation, continuous wave modulation, and the like) laser light to a target object, receives the laser light reflected by the target object, and calculates a time difference or a phase difference between emission and reflection to convert a distance between the target object and the laser source, thereby obtaining depth information of the target object.

Although the TOF module in the sweeping robot has higher cost performance, the TOF module has some disadvantages, and analysis is performed on the principle of the TOF technology, so that the measurement accuracy of the TOF module in optical ranging and the light field distribution projected by the emitting end of the TOF module have a very close relationship, and the TOF module mainly relates to two characteristic indexes of light power and light field distribution uniformity.

In the related technology, for the optical power, factors influencing the TOF module measurement accuracy mainly include a system error and a random error, in practical application, although the system error can be eliminated through means such as calibration and the like, the random error cannot be eliminated, and only the influence of the random error on the TOF module measurement accuracy can be reduced as much as possible, wherein the method for improving the signal-to-noise ratio is the simplest and most direct method, namely, the influence of the random error on the TOF module measurement accuracy can be effectively reduced by improving the optical power of the TOF module transmitting end, so that the TOF module measurement accuracy is improved. For the distribution uniformity of the light field, due to the design difficulty and the limitation of the processing technology, a certain deviation exists between the actual lens effect and the ideal situation, wherein the influence of the phase difference and the scattering on the TOF module is large, which is directly reflected in that the light received by a single pixel in the TOF module receiving end sensor is not only a corresponding object point in the imaging relation, but also has stray light reflected by other object points, so that when the light field projected by the TOF module transmitting end is uniform, the single pixel in the TOF module receiving end sensor is less influenced by the stray light; when the light field projected by the TOF module transmitting end is non-uniform, a single pixel in the TOF module receiving end sensor is greatly affected by stray light, in other words, the reflected light field is non-uniform, and has a large influence on the TOF module receiving end sensor, for example, a region with high reflected light intensity can have a relatively serious influence on a region with low reflected light, and a pixel is overexposed when the reflected light intensity is high, so that a measurement error is generated. The TOF module is applied to the sweeping robot, the TOF module needs to detect a scene in a large range, so the field angles of an emitting end and a receiving end of the TOF module are large, and a working scene of the sweeping robot is near the ground, so that the light field projected by the emitting end of the TOF module is high in light intensity after being reflected by the ground, and the reflected light intensity of a far ground area is low, so that pixels in the near ground area are over exposed, errors occur in measurement of the near ground area, and meanwhile, the TOF module can have very serious influence on the measurement accuracy of other far ground areas with low light intensity. Therefore, the TOF module can be applied to any scene needing optical ranging, such as a sweeping robot, a logistics robot (for delivering express delivery, taking out, and the like), a welcome robot, and the like. In this context, a robot cleaner will be described as an example.

Referring to fig. 1, fig. 1 is a light path diagram of the sweeping robot during optical distance measurement. In the process of performing ground cleaning work, the sweeping robot 10 performs optical ranging through the TOF module 11 carried by the sweeping robot, and since the working scene of the sweeping robot 10 is a near-ground scene, that is, it needs to acquire depth information of a larger field angle, or that is, an outgoing light field (that is, a solid line with an arrow in fig. 1) projected outward by the TOF module 11 needs a larger field angle, in the range of the outgoing light field, since the distance from the ground to the TOF module is far smaller than the far-ground field of view, the reflected light intensity at the near-ground position x is far greater than the reflected light intensity at the far-ground position y, so that an overexposure phenomenon occurs in a corresponding pixel for detecting the near-ground data, and because the reflected light intensity between the near-ground position x and the far-ground position y is so great, the deviation of the optical ranging data finally obtained by the TOF module 11 is larger than that of the real data, which seriously affects the measurement accuracy of the TOF module 11. Therefore, the key points of the embodiment of the application are as follows: how to reduce the reflected light intensity difference between the near ground position x and the far ground position y in the emergent light field range, and solve the problem of near ground overexposure.

Referring to fig. 2, fig. 2 is a schematic view of a TOF module according to an embodiment of the present disclosure. The TOF module provided by the embodiment of the application comprises a shell 20, a light source 30 and a light modulation device 40; wherein, the light source 30 and the light modulation device 40 are both arranged in the housing 20, the light source 30 and the light modulation device 40 are spaced from each other, and the light modulation device 40 is located on the light path of the light source 30.

Specifically, the light source 30 is configured to emit an incident light beam a, and the light modulation device 40 is configured to modulate the incident light beam a to project the incident light beam a to a target area to form a corresponding emergent light field B, where a near-ground illuminance of the emergent light field B is smaller than a far-ground illuminance, where the near-ground illuminance is an illuminance of the emergent light field B at a near-ground position x of the target area, and the far-ground illuminance is an illuminance of the emergent light field B at a far-ground position y of the target area. In addition, herein, the number of the light sources 30 is not limited to one, and it may include one or more, and when the number of the light sources 30 is multiple, the plurality of light sources 30 may be arranged in a regular array (such as a rectangular array, a circular array, and a linear array, etc.), or may be arranged in an irregular random arrangement. As for the type of the Light source 30, it may include, but is not limited to, a Laser, an LED (Light-Emitting Diode), and a VCSEL (Vertical-Cavity Surface-Emitting Laser), which generally refers to an optically active device commonly used in the art that can emit an incident Light beam a in an infrared band (or other bands).

In practical applications, the light source 30 will emit an incident light beam a toward the light modulation device 40; when the incident beam a reaches the light modulation device 40, the light modulation device 40 modulates the incident beam a; after the modulation operation of the light modulation device 40 on the incident light beam a is finished, the light modulation device 40 projects the incident light beam to the target area to form a corresponding emergent light field B. It can be understood that, the near-ground illumination of the outgoing light field B after modulation of the incident light beam a by the light modulation device 40 is less than the far-ground illumination, so that compared with the conventional technology, the illumination of the outgoing light field B at the near-ground position x of the target area can be reduced, and the illumination of the outgoing light field B at the far-ground position y of the target area is increased or not changed, that is, the illumination difference between the near-ground position x and the far-ground position y within the outgoing light field B range can be reduced, and the problem of overexposure caused by the excessively high intensity of the reflected light at the near-ground position x can be solved, or the influence caused by the higher intensity of the near-ground position x within the outgoing light field B range compared with the lower measurement accuracy of the far-ground position y can be reduced, so that the measurement accuracy of the TOF module can be effectively improved.

In some embodiments, the illumination of the outgoing light field B at the near-ground position x of the target area can be reduced by deflecting the optical axis of the incident light beam A, and the illumination of the outgoing light field B at the far-ground position y of the target area can be increased or not changedThe illumination intensity. As an example, please refer to fig. 3 (1) and (2), in which fig. 3 (1) is a graph of an angle-illuminance relationship on a target area before an optical axis is deflected according to an embodiment of the present application, and fig. 3 (2) is a graph of an angle-illuminance relationship on a target area after an optical axis is deflected according to an embodiment of the present application; wherein alpha is ₁ ～α ₃ The entire field angle area of the outgoing light field B and the deflection made by the incoming light beam a is an upward deflection. As can be seen from comparing fig. 3 (1) and (2), after the optical axis of the incident beam a is deflected upward, the near-ground position x (i.e., α) within the range of the emergent light field B is obtained ₁ ～α ₂ ) The illuminance of the incident light beam a is obviously reduced, and the illuminance of the far ground position y (i.e. α 3) in the range of the emergent light field B is obviously improved, which indicates that deflecting the optical axis of the incident light beam a is indeed an effective technical means.

As an embodiment, the light modulation device 40 may include an optical axis deflecting element, and the optical axis deflecting element is used to deflect the optical axis of the incident light beam a. It is understood that the present embodiment is configured such that the light modulation device 40 is set as the optical axis deflecting element in consideration of the light modulation device 40 side, thereby achieving the deflecting work of the optical axis of the incident light beam a. In addition, it is necessary to explain that the optical axis deflecting element may include, but is not limited to, a deflecting prism, a mirror, an eccentric lens, and a micro-nano optical element, which generally refers to an optical device commonly used in the art that can implement an optical axis deflecting function.

As another embodiment, the TOF module provided in the embodiment of the present application may further include a rotating device in addition to the housing 20, the light source 30 and the light modulation device 40, and the rotating device is in driving connection with the housing 20. Specifically, the rotating device is used to drive the housing 20 to rotate (since the light source 30 and the light modulation device 40 are both disposed in the housing 20, when the rotating device drives the housing 20 to rotate, the light source 30 and the light modulation device 40 will rotate synchronously with the housing 20) to deflect the optical axis of the incident light beam a, so that the illuminance of the emergent light field B at the near-ground position x of the target area is reduced, and the illuminance at the far-ground position y of the target area is increased or unchanged. Here, it is necessary to explain that, when the rotating device is in an operating state (i.e., when the rotating device drives the housing 20 to rotate), the light modulation device 40 does not perform modulation on the incident light beam a by "making the near illuminance of the outgoing light field B smaller than the far illuminance", but serves to directly transmit the incident light beam a.

As can be seen, the present embodiment is different from the previous embodiment, and the present embodiment realizes the deflection operation of the optical axis of the incident beam a by rotating the TOF module (i.e., the whole of the housing 20, the light source 30, and the light modulation device 40) in consideration of the TOF module. In this manner, the light modulation device 40 only acts to directly transmit the incident light beam a, and does not modulate the incident light beam a any more such that the near-field illumination of the outgoing light field B is less than the far-field illumination.

It should be understood that the above-mentioned embodiments are only preferred implementations of the present embodiment, and are not the only limitations on the way of deflecting the optical axis of the incident light beam a; in this regard, a person skilled in the art can flexibly set the setting according to the actual application scenario based on the embodiment.

In some embodiments, the illumination of the emergent light field B at the near-ground position x of the target area can be reduced by adjusting the type of the emergent light field B, and the illumination of the emergent light field B at the far-ground position y of the target area can be increased or not changed. As an example, please refer to fig. 4 (1) and (2), fig. 4 (1) is a graph of an angle-illuminance relationship on a target area before asymmetric light field modulation provided in this embodiment, and fig. 4 (2) is a graph of an angle-illuminance relationship on a target area after asymmetric light field modulation provided in this embodiment; wherein alpha is ₁ ～α ₃ The adjustment to the type of the emergent light field B is an asymmetric adjustment, that is, the emergent light field B is an asymmetric light field. As can be seen from comparing fig. 4 (1) and (2), after the type of the emergent light field B is adjusted to be an asymmetric light field, the near-ground position x (i.e., α) within the range of the emergent light field B ₁ ～α ₂ ) The illuminance of the outgoing light field B is obviously reduced, and meanwhile, the illuminance of the far ground position y (namely alpha 3) in the range of the outgoing light field B is basically kept unchanged, which indicates that the adjustment of the type of the outgoing light field B is really an effective technical means. In addition, the former is deflected intoFor the embodiment of the optical axis of the outgoing beam a, the light energy utilization efficiency of the embodiment is higher.

As an embodiment, the light modulation device 40 may include a light field modulation element, and the light field modulation element is configured to modulate the incident light beam a to be projected to the target area to form a corresponding asymmetric light field, that is, to make the emergent light field B be an asymmetric light field. It is to be understood that the present embodiment realizes the adjustment of the type of the outgoing light field B by providing the light modulation device 40 as a light field modulation element. In addition, in this context, the light field modulation element may be a diffuser (diffuser), and the structure of the diffuser is designed asymmetrically, so that an asymmetric light field can be projected to the target region.

It should be understood that the above-mentioned embodiment is only a preferred implementation of the present embodiment, and is not the only limitation on the manner of adjusting the type of the outgoing light field B in the present embodiment; in this regard, those skilled in the art can flexibly set the setting according to the actual application scenario based on the embodiment.

In some embodiments, the illumination of the outgoing light field B at the near-ground position x of the target area can be reduced by adjusting the optical power projected by different areas of the light modulation device 40, and the illumination of the outgoing light field B at the far-ground position y of the target area can be increased or not changed.

As an implementation manner, please refer to fig. 5, fig. 5 is a second schematic structural diagram of a TOF module according to an embodiment of the present disclosure; wherein alpha is ₁ ～α ₂ Near ground area, α ₂ ～α ₃ Is the middle (directly front) region, α ₃ ～α ₄ Is the elevation (off-ground) area and in general the illumination required for the near-ground area is low, the illumination required for the middle area is moderate and the illumination required for the off-ground area is high. The light modulation device 40 may include a light power modulation element having a plurality of modulation regions 41, the plurality of modulation regions 41 respectively having different transmittances, the plurality of modulation regions 41 respectively corresponding to the plurality of light sources 30 (fig. 5 exemplifies three modulation regions 41 of the light power modulation element corresponding to three light sources 30).

Specifically, the modulation regions 41 are used to modulate the incident light beams a emitted by the respective light sources 30, so that the light powers of the respective projected light fields B projected by the modulation regions 41 are different from those of the other modulation regions 41 (assuming that the projected light fields B projected by the three modulation regions 41 of the light power modulation element in fig. 5 are B1, B2, and B3, respectively, the light powers between B1, B2, and B3 are different from each other). It can be understood that, in view of the light modulation device 40 side, the present embodiment realizes the adjustment of the optical power projected by different areas of the light modulation device 40 by dividing the light modulation device 40 into a plurality of modulation areas 41 respectively having different transmittances.

Of course, in other embodiments, we can still consider the light modulation device 40, but the transmittance is not considered any more, but the divergence angle is considered, that is, the light modulation device 40 is divided into a plurality of modulation regions 41 with different divergence angles respectively, so as to adjust the light power projected by different regions of the light modulation device 40. It should be noted here that, on the premise that the optical powers of all the light sources 30 are the same, the larger the divergence angle of the modulation region 41, the smaller the projected optical power, and the lower the illuminance of the projected outgoing light field B at the corresponding position of the target region.

As another embodiment, still referring to fig. 5, the light modulation device 40 may have a plurality of modulation regions 41, the plurality of modulation regions 41 correspond to the plurality of light sources 30 respectively, and the incident light beams a emitted by the plurality of light sources 30 have different optical powers respectively, so that the illuminance of the emergent light field B at the near-ground position x of the target area is reduced, and the illuminance at the far-ground position y of the target area is increased or unchanged. Here, it should be noted that, when the incident light beams a emitted by the plurality of light sources 30 have different optical powers, the light modulation device 40 does not perform modulation on the incident light beams a such that the near illuminance of the emergent light field B is smaller than the far illuminance, but directly transmits the incident light beams a, and at this time, since the optical powers of the incident light beams a emitted by the plurality of light sources 30 are different from each other, the optical powers projected by the plurality of modulation regions 41 of the light modulation device 40 are also different from each other.

As can be seen, the present embodiment is different from the previous embodiment, and the present embodiment realizes the adjustment of the optical power projected by different areas of the optical modulation device 40 by arranging the incident light beams a emitted by the plurality of light sources 30 to have different optical powers, respectively, in consideration of the light source 30. In this manner, the light modulation device 40 only functions to directly transmit the incident light beam a, and does not perform modulation on the incident light beam a such that the near-field illumination of the outgoing light field B is smaller than the far-field illumination.

It should be understood that the above-mentioned embodiments are only preferred implementations of the present embodiment, and are not the only limitations of the present embodiment on the manner of adjusting the optical power projected by different areas of the light modulation device 40; in this regard, those skilled in the art can flexibly set the setting according to the actual application scenario based on the embodiment.

In some embodiments, the illumination of the outgoing light field B at the near-ground position x of the target area can be reduced by adjusting the luminous flux of the incident light beam a on different areas of the light modulation device 40, and the illumination of the outgoing light field B at the far-ground position y of the target area can be increased or not changed.

As an embodiment, please refer to fig. 6, wherein fig. 6 is a third structural schematic diagram of a TOF module according to an embodiment of the present disclosure; wherein alpha is ₁ ～α ₂ Near ground area, α ₂ ～α ₃ Is the middle (directly front) region, α ₃ ～α ₄ Is the elevation (off-ground) region. The light modulation device 40 may include a light flux modulation element having a plurality of modulation regions 41, the plurality of modulation regions 41 having different sizes, respectively. Here, it is necessary to explain that the size of the modulation region 41 is positively correlated with the luminous flux of the incident light beam a on the modulation region 41, i.e., the larger the modulation region 41 is, the larger the luminous flux of the incident light beam a on the modulation region 41 is; the smaller the modulation region 41, the smaller the luminous flux of the incident light beam a on the modulation region 41. In addition, compared to the previous embodiment using a plurality of light sources 30, the present embodiment may use only one light source 30.

It can be understood that, in the present embodiment, the plurality of modulation regions 41 of the light modulation device 40 are set to have different sizes, respectively, from the side of the light modulation device 40, so as to adjust the luminous flux of the incident light beam a on different regions of the light modulation device 40.

As another embodiment, the TOF module provided in this embodiment may further include a moving device disposed in the housing 20, in addition to the housing 20, the light source 30 and the light modulation device 40, wherein the moving device is in driving connection with the light source 30, and the light modulation device 40 has a plurality of modulation regions 41.

Specifically, the moving device is used to move the light source 30 (e.g., to a direction close to/away from the light modulation device 40, etc.) to adjust the luminous flux of the incident light beam a on each modulation region 41, so that the illuminance of the emergent light field B at the near-ground position x of the target region is reduced, and the illuminance at the far-ground position y of the target region is increased or unchanged. Here, it is necessary to explain that, when the moving device is in the operating state (i.e., when the moving device drives the light source 30 to move), the light modulation device 40 does not perform the modulation of the incident light beam a such that the near-earth illuminance of the outgoing light field B is smaller than the far-earth illuminance, but serves to directly transmit the incident light beam a.

As can be seen, the present embodiment is different from the previous embodiment, and the present embodiment realizes the adjustment of the luminous flux of the incident light beam a on different areas of the light modulation device 40 by moving the light source 30 in consideration of the light source 30. In this manner, the light modulation device 40 only acts to directly transmit the incident light beam a, and does not modulate the incident light beam a any more such that the near-field illumination of the outgoing light field B is less than the far-field illumination.

It should be understood that the above-described embodiment is only a preferred implementation of the present embodiment, and is not the only limitation on the manner of adjusting the luminous flux of the incident light beam a on different areas of the light modulation device 40 in the present embodiment; in this regard, a person skilled in the art can flexibly set the setting according to the actual application scenario based on the embodiment.

In summary, the embodiment of the present application provides a TOF module, which can reduce the illuminance of an outgoing light field B at a near-ground position x of a target area, and increase or not change the illuminance of the outgoing light field B at a far-ground position y of the target area, i.e., can reduce the illuminance difference between the near-ground position x and the far-ground position y within the outgoing light field B range, or that is, can reduce the influence caused by the higher near-ground position x of the illuminance within the outgoing light field B range to the lower measurement accuracy of the far-ground position y, so that the measurement accuracy of the TOF module can be effectively improved. In addition, although the TOF module is used in a cleaning robot, the TOF module is not limited to a cleaning robot, and may be used in a cleaning robot, such as a cleaning robot, or a cleaning robot.

It should be noted that, the embodiments in the present disclosure are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other.

It is further noted that, within the context of this application, relational terms such as first and second, and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined in this application may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (13)

1. A TOF module is characterized by comprising a shell, a light source and a light modulation device; the light source and the light modulation device are arranged in the shell, the light source and the light modulation device are spaced from each other, and the light modulation device is positioned on a light path of the light source;

the light source is used for emitting incident light beams;

the light modulation device is used for modulating the incident light beams to project to a target area to form a corresponding emergent light field, and the near-ground illumination of the emergent light field is smaller than the far-ground illumination;

the near-ground illumination is the illumination of the emergent light field at a near-ground position of the target area, and the far-ground illumination is the illumination of the emergent light field at a far-ground position of the target area.

2. The TOF module of claim 1 wherein the light modulating device comprises an optical axis deflecting element for deflecting an optical axis of the incident light beam.

3. The TOF module of claim 2 wherein the optical axis deflecting element comprises any of a deflecting prism, a mirror, an eccentric lens, and a micro-nano optical element.

4. The TOF module of claim 1 further comprising a rotating device drivingly connected to said housing;

the rotating device is used for driving the shell to rotate so as to deflect the optical axis of the incident light beam, so that the near-ground illumination of the emergent light field is smaller than the far-ground illumination; wherein the light source and the light modulation device rotate synchronously when the housing rotates; when the rotating device is in an operating state, the light modulation device is used for directly transmitting the incident light beam.

5. The TOF module of claim 1 wherein the light modulating device comprises a light field modulating element for modulating the incident light beam to form a corresponding asymmetric light field for projection onto the target region.

6. The TOF module of claim 1, wherein the light source comprises a plurality of light sources arranged in an array.

7. The TOF module of claim 6 wherein the light modulating device comprises a light power modulating element having a plurality of modulating regions, the plurality of modulating regions respectively having different transmittances, the plurality of modulating regions respectively corresponding to a plurality of the light sources;

the modulation regions are used for modulating the incident light beams emitted by the corresponding light sources, so that the optical power of the corresponding emergent light fields projected by the modulation regions is different from that of the emergent light fields projected by other modulation regions.

8. The TOF module of claim 6 wherein the light modulating device includes a light power modulating element having a plurality of modulation regions respectively having different divergence angles, the plurality of modulation regions respectively corresponding to a plurality of the light sources;

the modulation regions are used for modulating the incident light beams emitted by the corresponding light sources, so that the optical power of the corresponding emergent light fields projected by the modulation regions is different from that of the emergent light fields projected by other modulation regions.

9. The TOF module of claim 6 wherein the light modulating device has a plurality of modulating regions corresponding to a plurality of the light sources, respectively, the incident light beams emitted by the plurality of light sources having different optical powers, respectively, such that the near illumination of the outgoing light field is less than the far illumination; when the incident light beams emitted by the plurality of light sources respectively have different optical powers, the light modulation device is used for directly transmitting the incident light beams.

10. The TOF module of claim 1 wherein the light modulating device comprises a light flux modulating element having a plurality of modulating regions, the plurality of modulating regions each having a different size; wherein the size of the modulation region is positively correlated with the luminous flux of the incident light beam on the modulation region.

11. The TOF module of claim 1, further comprising a moving device disposed within the housing, the moving device in driving connection with the light source, the light modulating device having a plurality of modulation regions;

the moving device is used for moving the light source to adjust the luminous flux of the incident light beam on each modulation region, so that the near-ground illumination of the emergent light field is smaller than the far-ground illumination; when the mobile device is in an operating state, the light modulation device is used for directly transmitting the incident light beam.

12. The TOF module of any of claims 1-11 wherein the type of light source comprises any of a laser, an LED, and a VCSEL.

13. A sweeping robot comprising a TOF module according to any one of claims 1 to 12.

Images