CN113156743A

CN113156743A - Infrared 3D surveys transmitting terminal module and degree of depth camera

Info

Publication number: CN113156743A
Application number: CN202110479233.4A
Authority: CN
Inventors: 陈柯有; 伍未名; 刘风雷
Original assignee: Zhejiang Crystal Optech Co Ltd
Current assignee: Zhejiang Crystal Optech Co Ltd
Priority date: 2021-04-29
Filing date: 2021-04-29
Publication date: 2021-07-23

Abstract

An infrared 3D detection transmitting end module and a depth camera relate to the technical field of optics and electronics. The infrared 3D detection transmitting end module comprises a light source group, a collimating mirror and a light beam shaper, wherein the collimating mirror and the light beam shaper are sequentially arranged along the light outgoing direction of the light source group; the light source group is used for emitting light beams towards the corresponding first optical areas; the collimating mirror collimates and deflects the light beam through the first optical area to emit parallel light beams at a preset angle; the beam shaper is used for shaping the light beam emitted from the first optical area and projecting the shaped light beam to an object to be measured. This infrared 3D surveys emitter module can promote the integrated level that infrared 3D surveyed the emitter module, and then dwindles the whole volume of infrared 3D surveys the emitter module.

Description

Infrared 3D surveys transmitting terminal module and degree of depth camera

Technical Field

The invention relates to the technical field of optics and electronics, in particular to an infrared 3D detection transmitting end module and a depth camera.

Background

The 3D imaging technology is the core of a new generation of human-computer interaction technology, and can acquire depth information of a target object besides the capability of performing 2D imaging on the target object, and further realize functions such as 3D scanning, scene modeling, gesture interaction and the like according to the depth information. With the hard demand of 3D imaging technology for mobile terminal devices, depth cameras will be widely applied to mobile terminal devices.

The infrared 3D detection transmitting end module is based on core equipment in a structured light depth camera, and mainly aims to collimate light beams emitted by a light source group, emit a plurality of planar lights in different directions, and finally form a dot matrix projector by matching with a light beam shaper to project tens of thousands of points onto a measured object. And the three-dimensional information of the measured object is restored by identifying the points. In general, the size, power consumption, and performance of the structured light projection module determine the size, power consumption, and performance of the depth camera. However, the whole volume of the existing infrared 3D detection transmitting end module is large, and the uniformity of light intensity distribution in a large-range projection area is difficult to be guaranteed.

Disclosure of Invention

The invention aims to provide an infrared 3D detection transmitting end module and a depth camera, which can improve the integration level of the infrared 3D detection transmitting end module and further reduce the overall volume of the infrared 3D detection transmitting end module.

The embodiment of the invention is realized by the following steps:

in one aspect of the invention, an infrared 3D detection transmitting end module is provided, where the infrared 3D detection transmitting end module includes a light source group, and a collimating mirror and a beam shaper that are sequentially arranged along a light outgoing direction of the light source group, where the collimating mirror is divided into at least two first optical regions, the light source group includes at least two groups, and each group of light source group corresponds to one first optical region; the light source group is used for emitting light beams towards the corresponding first optical areas; the collimating mirror collimates and deflects the light beam through the first optical area to emit parallel light beams at a preset angle; the beam shaper is used for shaping the light beam emitted from the first optical area and projecting the shaped light beam to an object to be measured. This infrared 3D surveys emitter module can promote the integrated level that infrared 3D surveyed the emitter module, and then dwindles the whole volume of infrared 3D surveys the emitter module.

Optionally, the beam shaper is a diffractive optical element.

Optionally, the light source group comprises at least one point light source or at least one light source array.

Optionally, the light source group is a line light source or a surface light source.

Optionally, the two adjacent first optical regions are partially overlapped to form an overlapping region, and the overlapping region can respectively collimate and deflect the light beams incident from the light source groups corresponding to the two adjacent first optical regions.

Optionally, the infrared 3D detection transmitting end module further includes at least two light modulators, and the light modulators correspond to the light source groups one to one.

Optionally, the beam shaper is divided into at least two second optical regions, and the second optical regions correspond to the first optical regions one to one.

Optionally, two or three first optical regions are provided on the collimator lens.

Optionally, the deflection of the beam is the same for each point location within each first optical zone.

In an aspect of the present invention, a depth camera is provided, and the depth camera includes the infrared 3D probe transmitting end module. This degree of depth camera can promote the integrated level of infrared 3D survey transmitting terminal module, and then dwindles the whole volume of infrared 3D survey transmitting terminal module.

The beneficial effects of the invention include:

the application provides an infrared 3D detection transmitting end module, which comprises a light source group, a collimating mirror and a light beam shaper, wherein the collimating mirror and the light beam shaper are sequentially arranged along the light outgoing direction of the light source group; the light source group is used for emitting light beams towards the corresponding first optical areas; the collimating mirror collimates and deflects the light beam through the first optical area to emit parallel light beams at a preset angle; the beam shaper is used for shaping the light beam emitted from the first optical area and projecting the shaped light beam to an object to be measured. Therefore, when the device is used, light beams emitted by each group of light source groups can irradiate onto a first optical area of the collimating mirror corresponding to the light source group, so that the light beams are incident to a light beam shaper through collimation (or beam collection) of the first optical area and deflection in a specific direction, then the light beams are shaped through the light beam shaper, and finally the shaped light beams are projected onto an object to be measured. This application is through carrying out area division with the collimating mirror (divide into two at least first optical zone promptly), can still realize far field diffraction under the condition that does not need real focus, compare in prior art and need reach the effect of formation of image with the help of ordinary collimating mirror, thereby there is the restriction to the longitudinal length of light path (prior art needs the distance of light source to collimating mirror to be equal to the focus usually), this application proposes the thinking of designing novel collimating mirror from far field diffraction, can break through this restriction, with the longitudinal length who is less than the focus, realize same optical effect, consequently, this application has further improvement on the light path integration, can effectively reduce the volume of infrared 3D detection transmitting terminal module.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic diagram of an optical path of an infrared 3D detection transmitting end module according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a light source group and a collimating mirror according to an embodiment of the present invention;

FIG. 3 is a second schematic structural diagram of a light source set and a collimating mirror according to an embodiment of the present invention;

fig. 4 is a third schematic structural diagram of a light source group and a collimating mirror according to an embodiment of the present invention;

FIG. 5 is a schematic view of the excident light spot of FIG. 4;

FIG. 6 is a diagram of a far-field diffraction optical path corresponding to a divergent collimator according to an embodiment of the present invention;

FIG. 7 is a diagram of a far-field diffraction optical path corresponding to an arbitrarily-deflected collimator according to an embodiment of the present invention;

FIG. 8 is a diagram of a far field diffraction optical path of a common collimator provided in the prior art;

FIG. 9 is a schematic diagram of light paths of a light source group and a collimating mirror provided in an embodiment of the present invention;

fig. 10 is a schematic diagram of parallel optical paths of an infrared 3D detection transmitting end module according to an embodiment of the present invention;

fig. 11 is a schematic diagram of an emergent light spot of a parallel light path of an infrared 3D detection transmitting end module according to an embodiment of the present invention;

FIG. 12 is a schematic view of an overlap region provided by an embodiment of the present invention;

fig. 13 is a second schematic optical path diagram of the infrared 3D detection transmitting end module according to the embodiment of the present invention;

fig. 14 is a third schematic optical path diagram of the infrared 3D detection transmitting end module according to the embodiment of the present invention.

Icon: 10-a light source group; 20-a collimating mirror; 21-a first optical zone; 22-an overlap region; 30-a beam shaper; 31-a second optical zone; l-the spacing between the light source bank and the collimating mirror; EFL-equivalent focal length.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Referring to fig. 1, the present embodiment provides an infrared 3D detection transmitting end module, where the infrared 3D detection transmitting end module includes a light source group 10, and a collimator 20 and a beam shaper 30 sequentially arranged along a light outgoing direction of the light source group 10, where the collimator 20 is divided into at least two first optical regions 21, the light source group 10 includes at least two groups, and each group of the light source group 10 corresponds to one first optical region 21; the light source group 10 is used for emitting light beams towards the corresponding first optical regions 21; the collimating mirror 20 collimates and deflects the light beam through the first optical area 21 to emit parallel light beams at a preset angle; the beam shaper 30 is configured to shape the light beam emitted from the first optical area 21, and project the shaped light beam onto the object to be measured. This infrared 3D surveys emitter module can promote the integrated level that infrared 3D surveyed the emitter module, and then dwindles the whole volume of infrared 3D surveys the emitter module.

Wherein each group of light source groups 10 corresponds to one first optical area 21. Meanwhile, it should be noted that, in the present embodiment, the light source group 10 may include at least one point light source or at least one light source array. It should be noted that the infrared 3D detection transmitting end module provided in the present application is generally applied to the infrared band, so that the light beam emitted by the light source group 10 is required to belong to the infrared band correspondingly. For example, when the light source group 10 includes a point light source, it should be a first optical area 21 corresponding to a point light source, as shown in fig. 2; when the light source group 10 includes two point light sources, it should be a first optical area 21 corresponding to the two point light sources, as shown in fig. 3; when the light source group 10 includes a light source array, it should be a first optical area 21 corresponding to a light source array, as shown in fig. 4, and correspondingly, through the structure of the infrared 3D detection transmitting end module shown in fig. 4, the light spot pattern shown in fig. 5 can be obtained.

Of course, when a plurality of point light sources correspond to one first optical region 21, correspondingly, the light source group 10 should also include a plurality of light sources. For example, the light source group 10 may include three point light sources, four point light sources, or five point light sources, etc.

The light source group 10 may be a linear light source or a surface light source. As above, when the light source group 10 is a line light source or a surface light source, one or more light sources may be included.

The collimating mirror 20 is disposed in the light emitting direction of the light source group 10, and is used for collimating and deflecting the light beam emitted from the light source group 10. Specifically, in the present embodiment, at least two first optical regions 21 are divided on the collimator lens 20, as shown in fig. 1 (fig. 1 shows a case where the collimator lens 20 is divided into three first optical regions 21).

It should be noted that the number of divisions of the area of the collimator lens 20 is not limited in the present application, and those skilled in the art may divide the collimator lens 20 into two first optical areas 21, three first optical areas 21, or four first optical areas 21, for example, as the case may be.

The plurality of first optical regions 21 on the collimator lens 20 are respectively used for collimating and deflecting the light beams generated from the respective corresponding light source groups 10, so that parallel light beams are emitted at a predetermined angle.

The beam shaper 30 is configured to shape the light beam emitted from the first optical area 21, and project the shaped light beam onto an object to be measured, for example, when performing face recognition, correspondingly, the shaped light beam is projected onto a face. Alternatively, the beam shaper 30 may be a diffractive optical element or a refractive optical element, etc., to achieve various optical functions.

It should be noted that the present application provides a novel collimating mirror 20 (i.e. a collimating mirror 20 divided into at least two first optical regions 21), which has a spatially collimating effect, but does not necessarily have a true focal point. Because the working distance of the infrared 3D detection transmitting end module is much larger than the structure size of the infrared 3D detection transmitting end module, the infrared 3D detection transmitting end module belongs to far-field diffraction of light. Therefore, for the design and evaluation of the collimating mirror 20 of the present application, it should be judged in terms of the spot distribution of the far field diffraction.

As shown in fig. 6 to 8, fig. 6 is an optical path diagram of far-field diffraction corresponding to the divergent collimator lens 20, fig. 7 is an optical path diagram of far-field diffraction corresponding to the arbitrarily deflected collimator lens 20, and fig. 8 is an optical path diagram of far-field diffraction of the general collimator lens. It can be seen that the far field diffraction formed by the two new collimators 20 shown in fig. 6 and 7 and the conventional collimator shown in fig. 8 is substantially identical, and this is a possible solution for structured light for applications using far field diffraction. That is to say, it need not rely on "focus" through the infrared 3D detection transmitting terminal module that this application provided, as long as can appear required pattern in far field diffraction. The present application provides a collimating mirror 20 divided into a first optical zone 21, which may even be divergent, randomly arranged, as shown in fig. 6 and 7, which can achieve the same desired far field diffraction.

But simultaneously, this application can realize compressing the effect of the volume of whole infrared 3D detection transmitting terminal module through carrying out reasonable regional division (being the division of first optical zone 21) to collimating mirror 20. As shown in fig. 9, after the light beams emitted by each group of light source groups 10 are collimated and deflected by the respective first optical regions 21, the light beams all propagate toward the central optical axis, the convergence point of the light beams from different first optical regions 21 is the equivalent focal point (not the true focal point), and the distance between the collimating mirror 20 and the equivalent focal point is the equivalent focal length EFL. While a common collimating mirror converges an uncollimated light beam at a focal point of the central optical axis, which has a true focal point. Thus, the collimating mirror 20 with at least two first optical regions 21 can avoid the problem of large volume of the whole infrared 3D detection transmitting end module caused by having a real focus in the prior art.

In addition, for example, as shown in fig. 1, when the collimator lens 20 is divided into three first optical regions 21, the deflection directions of the light beams by the first optical regions 21 may be the same or different.

For example, when it is necessary that the deflection directions of the light beams of the respective areas by the three first optical areas 21 are different, correspondingly, the deflection in different directions can be realized by individually designing the respective structures of the three first optical areas 21. Since the first optical regions 21 have different structures when the first optical regions 21 deflect light beams in different directions, the structure of each first optical region 21 should be designed according to practical situations, and in practical applications, a person skilled in the art can design the structure of each first optical region 21 according to the deflection direction of each first optical region 21, so that the structure of each first optical region 21 is not limited in the present application.

Of course, in the present embodiment, the deflection action of each point position in each first optical area 21 on the light beam may be the same.

Referring to fig. 10 and fig. 11 in combination, fig. 10 shows that two groups of light source groups 10 respectively correspond to two first optical regions 21, and the two first optical regions 21 of the collimating mirror 20 have the same deflection angle (specifically, the deflection angles are both 0 °, that is, do not deflect), so that two parallel optical paths can be obtained correspondingly. Wherein, the far field diffraction light intensity distribution of the two parallel light paths should be the same. Since the two paths of optical paths are not coherent, the far field diffraction of the two paths can be directly superposed according to the light intensity (as shown in fig. 11), so that a diffraction order lattice can be obtained, and the light intensity of each diffraction order of the diffraction order lattice is the sum of the corresponding diffraction orders of the two optical paths. Thus, a complementary mechanism can be formed, and when an error occurs in one optical path, the error can be compensated by the other optical path. Only when all light paths have the same error, the light effect is obviously shown.

On the basis, the beam shaper 30 may be correspondingly divided into regions, that is, at least two second optical regions 31 are divided on the beam shaper 30, and the second optical regions 31 correspond to the first optical regions 21 one by one, as shown in fig. 14. The respective structures of each second optical region 31 may be the same or different.

When the respective structures of each second optical region 31 are different, the influence caused by the occurrence of the machining error or any random error of each second optical region 31 is generally different, so that the same optical error is difficult to occur in the infrared 3D detection transmitting end module provided by the present application. In this case, the complementary effect brought by the parallel light path structure can greatly improve the uniformity and stability of the optical system.

In summary, the present application provides an infrared 3D detection transmitting end module, which includes a light source group 10, and a collimating mirror 20 and a light beam shaper 30 sequentially arranged along a light outgoing direction of the light source group 10, wherein at least two first optical regions 21 are divided on the collimating mirror 20, the light source group 10 includes at least two groups, and each group of light source group 10 corresponds to one first optical region 21; the light source group 10 is used for emitting light beams towards the corresponding first optical regions 21; the collimating mirror 20 collimates and deflects the light beam through the first optical area 21 to emit parallel light beams at a preset angle; the beam shaper 30 is configured to shape the light beam emitted from the first optical area 21, and project the shaped light beam onto the object to be measured. Thus, in use, the light beam emitted by each light source group 10 will irradiate on the first optical region 21 of the collimating mirror 20 corresponding to the light source group 10, so as to enter the beam shaper 30 through collimation (or beam convergence) and deflection in a specific direction of the first optical region 21, then shape the light beam through the beam shaper 30, and finally project the shaped light beam onto the object to be measured. This application is through carrying out area division with collimating mirror 20 (divide into two at least first optical zone 21 promptly), can still realize far field diffraction under the condition that does not need real focus, compare in prior art and need reach the effect of formation of image with the help of ordinary collimating mirror, thereby there is the restriction to the longitudinal length of light path (prior art needs the interval L of light source group and collimating mirror generally apart from being approximately equal to the focus), this application proposes the thinking of designing novel collimating mirror 20 from far field diffraction, can break through this restriction, with the longitudinal length who is less than the focus, realize same optical effect, consequently, this application has further improvement on the light path integration, can effectively reduce the volume that infrared 3D surveyed the transmitting terminal module.

Also, in the present embodiment, optionally, as shown in fig. 12, an overlapping region 22 is formed by partially overlapping between two adjacent first optical regions 21, and the overlapping region 22 can collimate and deflect the light beams incident from the light source group 10 corresponding to each of the two adjacent first optical regions 21, respectively.

It should be noted that, the design of the structure of the overlapping region 22 can be designed by those skilled in the art according to the optical characteristics required by each of the two adjacent first optical regions 21, and the specific structure of the overlapping region 22 is not limited in the present application as long as the overlapping region 22 can simultaneously have the optical characteristics of the two adjacent first optical regions 21, in other words, after the light beam of each light source group 10 is incident on the first optical region 21 corresponding to the light beam, the deflection direction and the collimation effect thereof should not be changed (i.e. the same as when the light beam is incident on the first optical region 21 which is not overlapped).

This application is through being part overlap design between two adjacent first optical zone 21, can make the infrared 3D of this application survey transmitting terminal module have certain tolerance nature, it need not have obvious border necessarily, only need when infrared 3D surveys transmitting terminal module during operation each light source group 10 have more than 50% light intensity all to distribute in the first optical zone 21 that corresponds separately, regard as the region of having divided collimating mirror 20 from the design promptly, like this, can effectively simplify the segmentation mode of the first optical zone 21 on the collimating mirror 20.

Traditional infrared 3D surveys transmitting terminal module, its light source belongs to same light path essentially, so be difficult to realize the subregion illumination, this application divides collimating mirror 20 to two at least first optical zone 21, and sets up its independent light source group 10 corresponding to every first optical zone 21, and it can make the light path be divided into a plurality of independent sub-light paths, so can realize the effect of subregion illumination easily.

Specifically, referring to fig. 13, in order to realize the partitioned illumination, in the embodiment, the infrared 3D detection transmitting end module further includes at least two light modulators (not shown), and the light modulators correspond to the light source groups 10 one to one.

Wherein the light modulator is used to adjust optical parameters of the light source groups 10 (e.g., adjust color, intensity, etc. of each light source group 10) to enable each light source group 10 to emit light beams in a specific manner as desired.

The invention also provides a depth camera which comprises the infrared 3D detection transmitting end module. This degree of depth camera can promote the integrated level of infrared 3D survey transmitting terminal module, and then dwindles the whole volume of infrared 3D survey transmitting terminal module.

Since the specific structure and the beneficial effects of the infrared 3D detection transmitting end module are already described in detail in the foregoing, further description is omitted here.

The above description is only an alternative embodiment of the present invention and is not intended to limit the present invention, and various modifications and variations of the present invention may occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

Claims

1. An infrared 3D detection transmitting end module is characterized by comprising a light source group, and a collimating mirror and a light beam shaper which are sequentially arranged along the light outgoing direction of the light source group, wherein at least two first optical regions are divided on the collimating mirror, the light source group comprises at least two groups, and each group of the light source group corresponds to one first optical region;

the light source group is used for emitting light beams towards the corresponding first optical regions; the collimating mirror collimates and deflects the light beams through the first optical area to emit parallel light beams at a preset angle; the beam shaper is used for shaping the beam emitted from the first optical area and projecting the shaped beam to an object to be measured.

2. The infrared 3D detection transmit end module of claim 1, wherein the beam shaper is a diffractive optical element.

3. The infrared 3D detection emitter terminal module of claim 1, wherein the light source set comprises at least one point light source or at least one light source array.

4. The infrared 3D detection emission end module as claimed in claim 1, wherein the light source group is a line light source or a surface light source.

5. The infrared 3D detection transmitting end module according to claim 1, wherein an overlapping region is formed by partially overlapping two adjacent first optical regions, and the overlapping region can collimate and deflect light beams incident from a light source group corresponding to each of the two adjacent first optical regions.

6. The infrared 3D detection transmitting end module according to claim 1, further comprising at least two light modulators, wherein the light modulators are in one-to-one correspondence with the light source groups.

7. The infrared 3D probe transmitter end module as set forth in claim 1, wherein the beam shaper is divided into at least two second optical zones, and the second optical zones are in one-to-one correspondence with the first optical zones.

8. The infrared 3D detection transmitting end module of claim 1, wherein two or three first optical regions are disposed on the collimating mirror.

9. The infrared 3D detection transmitter module of claim 1, wherein the deflection of the beam is the same for each point location within each of the first optical zones.

10. A depth camera, comprising the infrared 3D detection transmitting end module set of any one of claims 1 to 9.