CN113514959A

CN113514959A - Projection module, imaging device and electronic equipment

Info

Publication number: CN113514959A
Application number: CN202110867194.5A
Authority: CN
Inventors: 陈驰; 李安; 张莉萍
Original assignee: Shenzhen Angstrong Technology Co ltd
Current assignee: Shenzhen Angstrong Technology Co ltd
Priority date: 2021-07-29
Filing date: 2021-07-29
Publication date: 2021-10-19

Abstract

The application provides a throw module, image device and electronic equipment, should throw the module and include: a light source for projecting structured light; the collimating mirror is arranged on the light emergent side of the light source and is used for collimating the structured light projected from the light source into parallel light; the diffractive optical element is arranged on the light emergent side of the collimating mirror; the diffractive optical element can be switched to a diffractive state and/or a diffusive state under the action of different voltages to diffract and/or scatter the parallel light projected from the collimator lens. The imaging device comprises an imaging module and a projection module; the electronic device includes an imaging device. Through adopting above-mentioned technical scheme, only set up the projection that a light source realized structure light and pan infrared light promptly, like this, saved the cost of manufacture of throwing the module, also reduced the volume of throwing the module simultaneously, help realizing imaging device's miniaturized design.

Description

Projection module, imaging device and electronic equipment

Technical Field

The application belongs to the technical field of optical imaging, and more particularly relates to a projection module, an imaging device and an electronic device.

Background

In the field of optical imaging, an imaging device for three-dimensional imaging mainly comprises a structured light projector, an infrared light supplement lamp, an infrared camera and a color camera. When the device works, the structured light projector projects structured light to a target object, the infrared camera receives the structured light to obtain an infrared image of the structural characteristics of the target object, and a depth image is obtained through an algorithm; the infrared light supplementing lamp projects the infrared light towards the target object, and the infrared camera receives the infrared light to obtain a uniform infrared image of the target object; a color camera acquires a color map of a target object. The uniform infrared image and the color image can perform face detection, face framing, face feature comparison, face recognition and other work in different scenes, the depth image increases the depth information of a target object, and plane attack means can be effectively responded. Like this, in brushing the face field, generally have two light sources of structured light projector and infrared light filling lamp on the image device, the cost of manufacture is higher, and image device's volume is great relatively, is unfavorable for image device's miniaturized design.

Disclosure of Invention

One of the purposes of the embodiment of the application is as follows: the utility model provides a throw the module, aims at solving prior art, adopts two light sources to lead to image device with high costs, bulky technical problem.

In order to solve the technical problem, the embodiment of the application adopts the following technical scheme:

there is provided a projection module, comprising:

a light source for projecting structured light;

the collimating mirror is arranged on the light-emitting side of the light source and is used for collimating the structured light projected from the light source into parallel light;

the diffractive optical element is arranged on the light emergent side of the collimating mirror; the diffractive optical element can be switched into a diffraction state and/or a diffusion state under the action of different voltages so as to diffract and/or scatter the parallel light projected from the collimating mirror.

In one embodiment, the diffractive optical element comprises a first microstructure arranged on the light-emitting side of the collimating mirror, and a plurality of first grooves distributed at intervals are arranged on one side of the first microstructure, which is far away from the collimating mirror; the first microstructure is made of polymer dispersed liquid crystal and can be switched into a transparent state and/or a diffusion state under the action of different voltages.

In one embodiment, the diffractive optical element further includes a transparent first substrate and a transparent second substrate, the first substrate and the second substrate are sequentially distributed along a light-emitting direction of the light source, and the first microstructure is sandwiched between the first substrate and the second substrate.

In one embodiment, the diffractive optical element includes a third substrate, a fourth substrate, and a transparent second microstructure, the third substrate and the fourth substrate are sequentially distributed along a light-emitting direction of the light source, the third substrate is disposed on a light-emitting side of the collimating mirror, and the second microstructure is sandwiched between the third substrate and the fourth substrate; a plurality of second grooves distributed at intervals are formed in one side, away from the third substrate, of the second microstructure;

the third substrate is made of polymer dispersed liquid crystal and can be switched into a transparent state and/or a diffusion state under the action of different voltages; or the material of the fourth substrate is polymer dispersed liquid crystal, and the fourth substrate can be switched into a transparent state and/or a diffusion state under the action of different voltages.

In one embodiment, the diffractive optical element includes a body portion and a diffuser portion; the main body part is arranged on the light-emitting side of the collimating mirror to diffract the structured light projected from the collimating mirror; the diffusion part is polymer dispersed liquid crystal and is arranged on the body part; the diffusion portion can be switched to a transparent state and/or a diffusion state by different voltages.

In one embodiment, the body portion includes a transparent third microstructure, the third microstructure is disposed on the light-emitting side of the collimating mirror, a plurality of third grooves distributed at intervals are disposed on a side of the third microstructure away from the collimating mirror, and the diffusion portion is disposed inside the third microstructure or on a side of the third microstructure along the light-emitting direction of the light source.

In one embodiment, the main body further includes a fifth transparent substrate and a sixth transparent substrate, the fifth and sixth substrates are sequentially distributed along a light emitting direction of the light source, and the third microstructure is sandwiched between the fifth and sixth substrates; the diffusion part is arranged in the fifth substrate, in the sixth substrate, on one side of the fifth substrate in the light emitting direction of the light source or on one side of the sixth substrate in the light emitting direction of the light source.

In one embodiment, the diffractive optical element comprises a diffractive region that can be switched to a diffractive state or a diffusive state under the action of different voltages;

alternatively, the diffractive optical element is divided into a plurality of diffractive regions, and each of the diffractive regions is switchable to a diffractive state or a diffusive state by a different voltage.

The embodiment also provides an imaging device, which comprises an imaging module and the projection module, wherein the imaging module is used for receiving the light projected by the projection module so as to image a target object.

The embodiment also provides electronic equipment, which comprises an electronic equipment body and the imaging device, wherein the imaging device is arranged on the electronic equipment body.

The beneficial effect of the projection module, imaging device and electronic equipment that this application embodiment provided lies in: compared with the prior art, the diffractive optical element can be switched into the diffraction state and/or the diffusion state under the action of different voltages. When the diffraction optical element is switched to a diffraction state, the collimating mirror collimates the structured light projected from the light source into parallel light, the parallel light is subjected to diffraction reaction in the diffraction optical element in the diffraction state and is projected to the outside, so that the projection module projects the structured light; when the diffraction optical element is switched to the diffusion state, the collimating mirror collimates the structured light projected from the light source into parallel light, the parallel light is subjected to diffusion reaction in the diffraction optical element in the diffusion state and is scattered to form the infrared light, so that the projection module projects the infrared light, and at the moment, the projection module plays a role of an infrared light supplement lamp. Therefore, the projection module provided by the embodiment is only provided with one light source, namely, the projection work of the structured light and the infrared light is realized, so that the manufacturing cost of the projection module is saved, the volume of the projection module is reduced, and the miniaturization design of the imaging device is facilitated. Correspondingly, the imaging device and the electronic equipment provided by the embodiment also have the advantages of the projection module.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic view of a projection module provided in an embodiment of the present application in a first operating mode;

fig. 2 is a schematic view of a projection module provided in the present application in a second operating mode;

fig. 3 is a first schematic view of a diffractive optical element of a projection module according to a first embodiment of the present disclosure;

fig. 4 is a second schematic view of a diffractive optical element of a projection module according to a first embodiment of the present disclosure;

fig. 5 is a first schematic view of a diffractive optical element of a projection module according to a second embodiment of the present disclosure;

fig. 6 is a second schematic view of a diffractive optical element of a projection module according to a second embodiment of the present disclosure;

fig. 7 is a first schematic view of a diffractive optical element of a projection module according to a third embodiment of the present application;

fig. 8 is a second schematic view of a diffractive optical element of a projection module according to a third embodiment of the present application;

fig. 9 is a schematic view of a main body portion of a diffractive optical element according to a fourth embodiment of the present application.

Wherein, in the figures, the respective reference numerals:

10-a light source; 20-a collimating mirror; 30-a diffractive optical element; 31-a first microstructure; 311-a first polymer matrix; 3111-a first recess; 3112-a first convex portion; 312-a first liquid crystal droplet; 32-a first substrate; 33-a second substrate; 34-a second microstructure; 341-second groove; 342-a second projection; 35-a third substrate; 351-a second polymer matrix; 352-second liquid crystal droplet; 36-a fourth substrate; 361-a third polymer matrix; 362-third liquid crystal droplet; 37-a body portion; 371-third microstructure; 3711-third groove; 3712-third projection; 372-a fifth substrate; 373-a sixth substrate; 40-a conductive film; 41-a first conductive film; 42-a second conductive film; x-a first direction.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present application and should not be construed as limiting the present application.

In the description of the present application, it is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, as used herein, refer to an orientation or positional relationship indicated in the drawings, which is for convenience and simplicity of description, and does not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus, is not to be considered as limiting.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise, wherein two or more includes two.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

The following detailed description is made with reference to the accompanying drawings and examples:

example one

Referring to fig. 1 and fig. 2, the projection module according to the embodiment of the present disclosure includes a light source 10, a collimating mirror 20, and a diffractive optical element 30, wherein the light source 10, the collimating mirror 20, and the diffractive optical element 30 are sequentially distributed at intervals along a first direction X; it should be understood that the collimating mirror 20 is disposed on the light-emitting side of the light source 10, and the diffractive optical element 30 is disposed on the light-emitting side of the collimating mirror 20. Note that the light source 10 is used to project structured light; the light source 10 may be a Vertical Cavity Surface Emitting Laser (VCSEL) or a Horizontal Cavity Surface Emitting Laser (HCSEL). The collimating mirror 20 is used for collimating the structured light projected by the light source 10 to collimate the structured light projected by the light source 10 into parallel light. In operation, the structured light projected by the light source 10 first passes through the collimating mirror 20, forms parallel light under the collimation effect of the collimating mirror 20, then projects to the diffractive optical element 30, and finally projects to an external target object from the diffractive optical element 30.

The diffractive optical element 30 can be switched to a diffractive state and/or a diffusive state under the action of different voltages; it will be appreciated that the switching of the state of the diffractive optical element 30 under different voltages has three cases: in the first case, the diffractive optical element 30 is switched to the diffraction state to diffract the parallel light; in the second case, the diffractive optical element 30 is switched to the diffusion state to perform the scattering action on the parallel light; in the third case, when one part of the diffractive optical element 30 is switched to the diffraction state and the other part is switched to the diffusion state, the diffractive optical element 30 is simultaneously switched to the diffraction state and the diffusion state so as to diffract a part of the parallel light beams in a divided region and diffuse the other part of the parallel light beams.

The diffractive optical element 30 is provided with a conductive film 40, the conductive film 40 includes a first conductive film 41 and a second conductive film 42, and the first conductive film 41 and the second conductive film 42 are sequentially distributed on the diffractive optical element 30 along the first direction X; the first conductive film 41 and the second conductive film 42 are provided with electrodes, and an external voltage device controls the voltages of the first conductive film 41 and the second conductive film 42 through the electrodes, so that the diffractive optical element 30 is under different voltages, and is switched to a diffraction state and/or a diffusion state under the action of different voltages. The conductive film 40 may be formed by using nano indium tin metal oxide, carbon nanotube conductive film, nano silver wire, etc., and the material of the conductive film 40 is not limited herein.

Optionally, in this embodiment, when the conductive film 40 is powered on and the voltages of the first conductive film 41 and the second conductive film 42 are at the preset value, the diffractive optical element 30 is switched to the diffraction state; when the conductive film 40 is not energized, the diffractive optical element 30 is switched to the diffusion state.

It should be noted that, as shown in fig. 1, fig. 1 is a schematic diagram of the projection module in a first operation mode, in which the diffractive optical element 30 is in a diffractive state. The light source 10 projects structured light to the collimating mirror 20; the collimating lens 20 collimates the structured light projected by the light source 10, collimates the structured light into parallel light, and then projects the parallel light to the diffractive optical element 30 in a diffraction state; the diffractive optical element 30 diffracts the parallel light projected from the collimator lens 20, specifically, performs diffraction, beam expansion and replication on the parallel light, and finally projects the structured light after beam expansion and replication onto an external target object. So, throw the module and will throw to the target object through the structured light after collimation, diffraction effect on, help outside formation of image module based on this structured light discernment target object to carry out imaging work to target object, thereby obtain the infrared figure of taking the structure characteristic, in order to help the acquireing of follow-up degree of depth map.

It should be noted that, as shown in fig. 2, fig. 2 is a schematic diagram of the projection module in the second operation mode, in which the diffractive optical element 30 is in a diffusion state. The structured light projected by the light source 10 is projected to the collimating mirror 20 to be collimated by the collimating mirror 20 to form parallel light, then the parallel light is projected to the diffractive optical element 30 in a diffusion state, and the diffractive optical element 30 diffuses the parallel light to form infrared light, and finally the infrared light is projected to an external target object. Therefore, the projection module projects the infrared light to the target object at the moment, and the external imaging module is facilitated to identify the target object based on the infrared light so as to perform imaging work on the target object, so that a uniform infrared image is obtained; it can be understood that the module of throwing at this moment can be regarded as infrared light filling lamp, has played the effect of infrared light filling to make the imaging module acquire even infrared picture.

In the embodiment of the present application, the diffractive optical element 30 can be switched to the diffractive state and/or the diffusive state by different voltages. When the diffractive optical element 30 is switched to the diffraction state, the collimating mirror 20 collimates the structured light projected from the light source 10 into parallel light, which is subjected to a diffraction reaction in the diffractive optical element 30 in the diffraction state and is projected to the outside, so that the projection module projects the structured light; when the diffractive optical element 30 is switched to the diffusion state, the collimating lens 20 collimates the structured light projected from the light source 10 into parallel light, the parallel light undergoes a diffusion reaction in the diffractive optical element 30 in the diffusion state and is scattered to form infrared light, so that the projection module projects the infrared light, and at this time, the projection module plays a role of an infrared fill light. Therefore, the projection module provided by the embodiment is provided with only one light source 10, namely, the projection work of the structured light and the infrared light is realized, so that the manufacturing cost of the projection module is saved, the volume of the projection module is reduced, and the miniaturization design of the imaging device is facilitated.

In one embodiment, referring to fig. 1 to 4, the diffractive optical element 30 includes a first microstructure 31, the first microstructure 31 is disposed on the light-emitting side of the collimating mirror 20, and a plurality of first grooves 3111 spaced apart from each other are disposed on a side of the first microstructure 31 away from the collimating mirror 20; the first microstructures 31 are made of polymer dispersed liquid crystal, that is, the first microstructures 31 are made of polymer dispersed liquid crystal.

Under the action of different voltages, the first microstructures 31 can be switched to a transparent state, so that the first microstructures 31 are in a diffraction state; and/or the first microstructure 31 is switched to a diffused state. It is understood that the first microstructures 31 are switched to a transparent state, or the first microstructures 31 are switched to a diffused state, or a part of the first microstructures 31 are switched to a transparent state and another part are switched to a diffused state.

It should be noted that the first conductive film 41 and the second conductive film 42 are respectively disposed on two opposite sides of the first microstructure 31 along the first direction X, and both the first conductive film 41 and the second conductive film 42 are externally connected to an external voltage device through electrodes; an external voltage device controls the voltage between the first conductive film 41 and the second conductive film 42 through the electrodes, so that the first microstructures 31 can be in different voltages, and the first microstructures 31 can be switched into a transparent state and/or a diffusion state under the action of different voltages. When the first conductive film 41 and the second conductive film 42 are powered on and the voltage is at a preset value, the state of the first microstructure 31 corresponding to the first conductive film 41 and the second conductive film 42 is switched to a transparent state, and based on that a plurality of first grooves 3111 distributed at intervals are arranged on one side of the first microstructure 31 departing from the collimating mirror 20, the first microstructure 31 has a diffraction effect, that is, the first microstructure 31 is in a diffraction state at this time; when the first conductive film 41 and the second conductive film 42 are not energized, the first microstructures 31 corresponding to the first conductive film 41 and the second conductive film 42 are switched to a diffusion state.

In a particular embodiment, the first microstructure 31 includes a first polymer matrix 311 and a plurality of first liquid crystal droplets 312, the plurality of first liquid crystal droplets 312 being dispersed on the first polymer matrix 311. When the first conductive film 41 and the second conductive film 42 are not energized, the optical axis of the first liquid crystal droplet 312 is in a free orientation, and the refractive index of the first liquid crystal droplet 312 is different from the refractive index of the first polymer matrix 311, and at this time, the first microstructure 31 corresponding to the first conductive film 41 and the second conductive film 42 is in a diffused state; when the parallel light projected from the collimator lens 20 passes through the first microstructure 31 in the diffusion state, the parallel light is scattered on the first microstructure 31 to form a bright infrared light, so as to be projected onto an external target object. When the first conductive film 41 and the second conductive film 42 are energized, the first liquid crystal droplet 312 changes its optical axis orientation under the action of voltage, and when the voltage of the first conductive film 41 and the second conductive film 42 is at a preset value, the refractive index of the first liquid crystal droplet 312 changes, and changes to be the same as the refractive index of the first polymer matrix 311, and then the first microstructure 31 corresponding to the first conductive film 41 and the second conductive film 42 is in a transparent state; based on the design of the first groove 3111, when the first microstructure 31 is in a diffraction state, parallel light projected from the collimating mirror 20 passes through the first microstructure 31 in the diffraction state, and the parallel light is expanded and replicated on the first microstructure 31, and finally projected onto an external target object.

Through adopting above-mentioned technical scheme, first micro-structure 31 adopts the material of polymer dispersed liquid crystal to make, make first micro-structure 31 just can switch into diffraction state and/or diffusion state respectively through its self structure, can understand, diffraction function and diffusion function have been integrateed on the first micro-structure 31, thereby make the module of throwing throw out structure light and/or pan infrared light selectively, need not additionally to set up and be used for scattering the optical element of structure light for pan infrared light, thus, the use of the optical element who throws the module has been reduced, the cost of manufacture of the module of throwing has been saved, the volume of the module of throwing has also been reduced simultaneously, help further realizing imaging device's miniaturized design.

It should be further noted that a plurality of first grooves 3111 are disposed on a side of the first microstructure 31 away from the collimating mirror 20, that is, a plurality of first grooves 3111 are disposed on a light exit side of the first microstructure 31, and the plurality of first grooves 3111 are distributed at intervals on the light exit side of the first microstructure 31; correspondingly, the light-emitting side of the first microstructure 31 is provided with a plurality of first protrusions 3112 distributed at intervals, and the first protrusions 3112 and the first grooves 3111 are arranged adjacently, so that the light-emitting side of the first microstructure 31 is designed to be uneven. Thus, when the first microstructure 31 is in a transparent state, the first protrusion 3112 and the first groove 3111 on the light exit side of the first microstructure 31 are distributed, so that the optical paths of different incident lights emitted from the light exit side of the first microstructure 31 are different, and the phase of the incident lights is modulated by changing the optical path difference of the incident lights, thereby obtaining the structured light after being copied and expanded. The distribution of the first grooves 3111 and the first protrusions 3112 is designed according to the diffraction performance of the first microstructure 31, and may be regular or irregular, which is not limited herein.

In a specific embodiment, the first conductive film 41 and the second conductive film 42 are sequentially distributed along the first direction X, such that the first conductive film 41 is disposed on a side of the first microstructure 31 close to the collimating mirror 20 along the first direction X, and the second conductive film 42 is disposed on a side of the first microstructure 31 away from the collimating mirror 20 along the first direction X, that is, the second conductive film 42 is disposed on the first groove 3111 and/or the first protrusion 3112 of the first microstructure 31. Alternatively, the first conductive film 41 and the second conductive film 42 are respectively plated on two opposite sides of the first microstructure 31 along the first direction X.

In one embodiment, referring to fig. 3 and fig. 4, the diffractive optical element 30 further includes a first substrate 32 and a second substrate 33, and the first substrate 32 and the second substrate 33 are both in a transparent state. The collimating lens 20, the first substrate 32 and the second substrate 33 are sequentially distributed along a first direction X, the first microstructure 31 is clamped between the first substrate 32 and the second substrate 33, and the first substrate 32 is arranged on the light-emitting side of the collimating lens 20; it can be understood that the first protrusion 3112 and the first groove 3111 of the first microstructure 31 are disposed on a side of the first microstructure 31 close to the second substrate 33. It should be noted that the parallel light projected from the collimator lens 20 passes through the first substrate 32, the first microstructure 31 and the second substrate 33 in sequence, and then is projected onto an external target object; it should be further noted that the arrangement of the first substrate 32 and the second substrate 33 is helpful for realizing the packaging and protecting effects of the first microstructure 31, and ensuring the usability of the first microstructure 31.

In order to facilitate the light to transmit through the first substrate 32 and the second substrate 33, the first substrate 32 and the second substrate 33 are made of a material with high transmittance, and optionally, the first substrate 32 and the second substrate 33 are made of an alkaline earth boro-aluminosilicate glass material.

It should be noted that the first conductive film 41 and the second conductive film 42 are respectively disposed on two opposite sides of the first microstructure 31 along the first direction X, the first conductive film 41 is disposed between the first microstructure 31 and the first substrate 32, and the second conductive film 42 is disposed between the first microstructure 31 and the second substrate 33, so that the first microstructure 31, the first conductive film 41, and the second conductive film 42 are sandwiched between the first substrate 32 and the second substrate 33; a second conductive film 42 is disposed between the first protrusion 3112 and the second substrate 33, and/or a second conductive film 42 is disposed between the first groove 3111 and the second substrate 33.

In one embodiment, referring to fig. 1 to 4, the diffractive optical element 30 includes a diffractive region capable of being switched to a diffractive state or a diffusive state under different voltages; alternatively, the diffractive optical element 30 is divided into a plurality of diffraction regions, the distribution planes of the plurality of diffraction regions are perpendicular to the first direction X, and each diffraction region can be switched to a diffraction state or a diffusion state by different voltages.

It should be noted that the diffractive optical element 30 includes one diffractive region, and it is understood that the entire diffractive optical element 30 is one diffractive region, and the entire diffractive optical element 30 is switched to the diffractive state or the diffusive state under the action of different voltages; alternatively, the first microstructure 31 of the diffractive optical element 30 is used to switch states, the first microstructure 31 comprises one diffractive region, and the entire first microstructure 31 is one diffractive region. As shown in fig. 3, fig. 3 illustrates a schematic view of the first microstructure 31 having only one diffractive region; the first conductive film 41 and the second conductive film 42 are respectively disposed on two opposite sides of the first microstructure 31 along the first direction X and are disposed correspondingly, and if the first conductive film 41 and the second conductive film 42 are both disposed as one, the first groove 3111 disposed on the first microstructure 31 and the second conductive film 42 disposed on the first protrusion 3112 are continuously disposed to form a second conductive film 42 by connection; in this way, an external voltage device can adjust the voltage between the first conductive film 41 and the second conductive film 42 to enable the entire first microstructure 31 to be in different voltage states, and then the first microstructure 31 can be switched to a diffraction state or a diffusion state under different voltages, so that the imaging device can acquire an infrared image or a uniform infrared image with a band structure characteristic.

It should be noted that the diffractive optical element 30 is divided into a plurality of diffractive regions, and it is understood that the diffractive optical element 30 is composed of a plurality of diffractive regions, and the distribution direction of the plurality of diffractive regions is perpendicular to the first direction X, so that each diffractive region can be switched to a diffractive state or a diffusive state under the action of different voltages; alternatively, the first microstructure 31 is used for switching the state, the first microstructure 31 is divided into a plurality of diffraction regions, that is, the first microstructure 31 is composed of a plurality of diffraction regions, the distribution direction of the plurality of diffraction regions is perpendicular to the first direction X, and each diffraction region of the first microstructure 31 can be switched to the diffraction state or the diffusion state under the action of different voltages. As shown in fig. 4, fig. 4 illustrates a schematic view in which the first microstructure 31 is divided into a plurality of diffraction regions; the first conductive films 41 and the second conductive films 42 are respectively arranged on two opposite sides of the first microstructure 31 along the first direction X, the first conductive films 41 and the second conductive films 42 are arranged in a plurality, and the plurality of first conductive films 41 and the plurality of second conductive films 42 are arranged in a one-to-one correspondence manner along the first direction X, so that one side of the first microstructure 31 is provided with the plurality of discontinuously arranged first conductive films 41, and the other side of the first microstructure 31 is provided with the plurality of discontinuously arranged second conductive films 42; further, the first conductive film 41 and the second conductive film 42 are disposed on opposite sides of each diffraction region in the first direction X, and one first conductive film 41 and one second conductive film 42 are disposed in correspondence to each other to adjust the voltage of the corresponding one diffraction region under the control of an external voltage device, so that each diffraction region can be switched to a diffraction state or a diffusion state at different voltages. Wherein, each diffraction region is provided with a first conductive film 41 and a second conductive film 42 along two opposite sides of the first direction X, and each first conductive film 41 and each second conductive film 42 can be controlled by an external voltage device, so that the external voltage device can individually control the voltage of each diffraction region through the first conductive film 41 and the second conductive film 42, thereby realizing the adjustment of individually switching the state of each diffraction region.

As can be understood, according to the actual imaging requirement, if only the infrared image of the band structure feature needs to be obtained, the voltage device adjusts the voltages between the plurality of first conductive films 41 and the plurality of second conductive films 42 to control the voltages of all the diffraction regions of the first microstructures 31, so that all the diffraction regions are switched to the diffraction state, and then the parallel light passing through all the diffraction regions is still projected to the external target object in the form of structured light after undergoing the diffraction replication and beam expansion reactions, so that the imaging module can obtain the infrared image of the band structure feature of the target object based on the structured light during imaging; accordingly, if only a uniform infrared pattern needs to be obtained, the voltage device can also adjust the voltages between the plurality of first conductive films 41 and the plurality of second conductive films 42 to control the voltages of all the diffraction regions so that all the diffraction regions are switched to the diffusion state, and then the parallel light passing through all the diffraction regions is projected to an external target object in the form of the infrared light after being subjected to the scattering effect, so that the imaging module can obtain the uniform infrared pattern of the target object based on the infrared light during imaging.

It can also be understood that the voltages of the plurality of diffraction regions of the first microstructure 31 can be individually controlled by the first conductive film 41 and the second conductive film 42 by an external voltage device, so that each diffraction region can be switched to the diffraction state or the diffusion state under the action of different voltages, and the external voltage device can control the voltage between a part of the first conductive film 41 and the second conductive film 42, so that a part of the diffraction regions of the first microstructure 31 is switched to the diffraction state, and another part of the diffraction regions of the first microstructure 31 is switched to the diffusion state, so that a part of the diffraction regions of the first microstructure 31 is in the diffraction state, and another part of the diffraction regions is in the diffusion state; when the parallel light projected from the collimator lens 20 is projected to an external target object through the diffractive optical element 30, a part of the parallel light passes through the diffusion region in the diffraction state and is projected from the diffraction region to the target object in the form of structured light, and another part of the parallel light passes through the diffraction region in the diffusion state and is scattered, so that the parallel light is projected to the external target object in the form of the infrared light. Therefore, the diffractive optical element 30 is matched with one light source 10, so that the projection module can project mutually independent structural light and infrared light, when the external imaging module performs imaging operation, the infrared image of the target object acquired by the external imaging module has parts of the infrared image with the band structure characteristics and parts of the uniform infrared image, and thus, the imaging module acquires two types of infrared images at one time based on the state of the target object under the illumination of the structural light and the infrared light at the same time, the type of acquiring the infrared images by an algorithm is increased, and the safety and the attack resistance of identification are improved.

Example two

Referring to fig. 1, 2, 5 and 6, the projection module of the present embodiment has substantially the same structure as the first embodiment, except for the specific structure of the diffractive optical element 30; the diffractive optical element 30 includes a third substrate 35, a fourth substrate 36, and a second microstructure 34, the collimating mirror 20, the third substrate 35, and the fourth substrate 36 are sequentially distributed along the first direction X, the third substrate 35 is disposed on the light-emitting side of the collimating mirror 20, and the second microstructure 34 is sandwiched between the third substrate 35 and the fourth substrate 36. The third substrate 35 and the fourth substrate 36 are arranged to protect the second microstructure 34; in operation, the parallel light projected from the collimator lens 20 passes through the third substrate 35, the second microstructure 34 and the fourth substrate 36 in sequence, and then is projected to an external target object.

It should be noted that the structure of the second microstructure 34 is the same as that of the first microstructure 31 in the first embodiment, but the material of the second microstructure 34 is different from that of the first microstructure 31, the second microstructure 34 is not made of a polymer dispersed liquid crystal material, but is in a transparent state, and optionally, the second microstructure 34 is made of a high-transmittance quartz or glass material. A plurality of second grooves 341 are formed in a side of the second microstructure 34 away from the third substrate 35, that is, a plurality of second grooves 341 are formed in the light emergent side of the second microstructure 34, and the plurality of second grooves 341 are distributed at intervals; correspondingly, the light-emitting side of the second microstructure 34 is provided with a plurality of second protrusions 342 distributed at intervals, the second protrusions 342 and the second grooves 341 are arranged adjacently, and the light-emitting side of the second microstructure 34 is designed to be uneven. Thus, the second grooves 341 and the second protrusions 342 on the light-emitting side of the second microstructure 34 are distributed, so that the light paths of different incident lights emitted from the light-emitting side of the second microstructure 34 are different, the phase of the incident light is modulated by changing the optical path difference of the incident light, and the emergent light after being copied and expanded is obtained, so that the second microstructure 34 realizes the diffraction effect. The distribution of the second grooves 341 and the second protrusions 342 needs to be designed according to the diffraction performance of the second microstructure 34, and may be regular or irregular, which is not limited herein. Wherein the second recess 341 and the second protrusion 342 are both disposed on a side of the second microstructure 34 facing away from the third substrate 35.

The third substrate 35 has the same structure as the first substrate 32 in the first embodiment, but the material of the third substrate 35 is different from that of the first substrate 32, and the third substrate 35 is made of a polymer dispersed liquid crystal material. Under the action of different voltages, the third substrate 35 can be switched to a transparent state, so that the diffractive optical element 30 is in a diffractive state; and/or the third substrate 35 can be switched to a diffusive state, so that the diffractive optical element 30 is in a diffusive state. As will be appreciated, the third substrate 35 is switched to the transparent state, so that the diffractive optical element 30 is in the diffractive state; alternatively, the third substrate 35 is switched to the diffusing state so that the diffractive optical element 30 is in the diffusing state; alternatively, a part of the third substrate 35 is switched to the transparent state and the other part is switched to the diffusing state, so that a part of the diffractive optical element 30 is switched to the diffractive state and the other part is switched to the diffusing state.

The structure of the fourth substrate 36 is the same as that of the second substrate 33 in the first embodiment, and both are in a transparent state, and the material of the fourth substrate 36 is the same as that of the second substrate 33.

It should be noted that the first conductive film 41 and the second conductive film 42 are respectively disposed on two opposite sides of the third substrate 35 along the first direction X, and optionally, the first conductive film 41 and the second conductive film 42 are electroplated on two opposite sides of the third substrate 35 along the first direction X. Thus, the first conductive film 41 is disposed on the third substrate 35 on the side close to the collimator lens 20 in the first direction X, and the second conductive film 42 is disposed between the third substrate 35 and the second microstructure 34.

It is further noted that the third substrate 35 includes a second polymer matrix 351 and a plurality of second liquid crystal droplets 352, and the plurality of second liquid crystal droplets 352 are dispersedly disposed on the second polymer matrix 351. When the first conductive film 41 and the second conductive film 42 on the third substrate 35 are energized and the voltage is set to a preset value, the refractive index of the second polymer matrix 351 is the same as that of the second liquid crystal droplet 352, so that the third substrate 35 corresponding to the first conductive film 41 and the second conductive film 42 is in a transparent state, and parallel light projected from the collimator lens 20 passes through the third substrate 35 in the transparent state, then passes through the diffraction beam expansion and replication action of the second microstructure 34, and finally passes through the transparent fourth substrate 36 to be projected to an external target object in the form of structured light; at this time, the diffractive optical element 30 corresponding to the first conductive film 41 and the second conductive film 42 is in a diffraction state. When the first conductive film 41 and the second conductive film 42 on the third substrate 35 are not energized, and the refractive index of the second polymer matrix 351 is different from the refractive index of the second liquid crystal droplet 352, the third substrate 35 corresponding to the first conductive film 41 and the second conductive film 42 is in a diffusion state, the parallel light projected from the collimator lens 20 firstly passes through the third substrate 35 in the diffusion state, and is scattered by the diffusion effect of the third substrate 35 to form a bright infrared light, then sequentially passes through the transparent second microstructure 34 and the fourth substrate 36, and finally is projected to an external target object; at this time, the diffractive optical element 30 corresponding to the first conductive film 41 and the second conductive film 42 is in a diffused state; after the parallel light is scattered by the third substrate 35 to form the infrared light, the second microstructure 34 does not diffract the light emitted from the third substrate 35 at this time, that is, does not diffract the infrared light.

Through adopting above-mentioned technical scheme, make third base plate 35 adopt the material of polymer dispersed liquid crystal to make, then third base plate 35 just can switch into transparent state or diffusion state respectively through its self structure, with corresponding make diffractive optical element 30 switch into diffraction state or diffusion state, thereby make the module of throwing throw out structured light or pan infrared light selectively, need not additionally to set up the optical element who is used for scattering structured light for pan infrared light, thus, the use of the optical element who throws the module has been reduced, the cost of manufacture of the module of throwing has been saved, the volume of the module of throwing has also been reduced simultaneously, help further realizing imaging device's miniaturized design.

In one embodiment, the third substrate 35 includes one diffraction region or includes a plurality of diffraction regions.

Alternatively, as shown in fig. 5, the third substrate 35 includes one diffraction region, the first conductive film 41 and the second conductive film 42 are disposed on two sides of the third substrate 35 along the first direction X, and the first conductive film 41 and the second conductive film 42 are both set as one, an external voltage device can adjust the voltage between the first conductive film 41 and the second conductive film 42, so that the entire third substrate 35 can be in different voltage states, and the third substrate 35 can be switched to the diffraction state or the diffusion state at different voltages, so that the imaging device can obtain an infrared image or a uniform infrared image with a band structure characteristic.

Alternatively, as shown in fig. 6, the third substrate 35 is divided into a plurality of the above-mentioned diffraction regions, the first conductive films 41 and the second conductive films 42 are respectively disposed on two opposite sides of the third substrate 35 along the first direction X, the first conductive films 41 and the second conductive films 42 are both disposed in plurality, the plurality of first conductive films 41 and the plurality of second conductive films 42 are disposed in one-to-one correspondence, and each diffraction region has the first conductive film 41 and the second conductive film 42 on two opposite sides along the first direction X; in this way, an external voltage device can cause each diffraction region to switch to the diffraction state or the diffusion state by individually controlling the voltage between the first conductive film 41 and the second conductive film 42 on the opposite sides of the diffraction region. In this way, an external voltage device can independently control the voltage between the first conductive film 41 and the second conductive film 42 on the plurality of diffraction regions, so that all the diffraction regions on the entire third substrate 35 are switched to be in a transparent state, and thus, parallel light projected from the collimator lens 20 passes through the third substrate 35, the second microstructure 34 and the fourth substrate 36 in sequence, and then undergoes diffraction replication and beam expansion reaction to be projected to an external target object, and then the imaging module can acquire an infrared image of a band structure characteristic based on the structured light; or, all the diffraction regions on the third substrate 35 are switched to a diffusion state, and the parallel light projected from the collimator lens 20 undergoes a scattering reaction after passing through the third substrate 35, the second microstructure 34, and the fourth substrate 36 in sequence, and is projected to an external target object in the form of uniform infrared light, so that the imaging module can obtain a uniform infrared image based on the uniform infrared light; alternatively, a part of the diffraction region on the third substrate 35 is switched to the transparent state and the other part of the diffraction region is switched to the diffused state, so that a part of the diffractive optical element 30 is switched to the diffraction state and the other part is switched to the diffused state.

The rest of this embodiment is the same as the first embodiment, and the unexplained features in this embodiment are explained by the first embodiment, which is not described herein again.

EXAMPLE III

Referring to fig. 7 and fig. 8, the present embodiment is substantially the same as the second embodiment except that: the material of the third substrate 35 is different from that of the third substrate 35 in the second embodiment, the third substrate 35 in this embodiment is in a transparent state, and optionally, the third substrate 35 is made of quartz or glass with high transmittance; the material of the fourth substrate 36 is different from that of the second substrate 33, and the material of the fourth substrate 36 is polymer dispersed liquid crystal.

As can be understood, the first conductive film 41 and the second conductive film 42 are respectively disposed on two opposite sides of the fourth substrate 36 along the first direction X, and an external voltage device controls the voltages of the first conductive film 41 and the second conductive film 42, so that the fourth substrate 36 is switched into the transparent state and/or the diffusion state under the action of different voltages. The first conductive film 41 is disposed between the fourth substrate 36 and the second microstructure 34, and the second conductive film 42 is disposed on a side of the fourth substrate 36 away from the second microstructure 34, and optionally, the first conductive film 41 and the second conductive film 42 are electroplated on two opposite sides of the fourth substrate 36 along the first direction X in an electroplating manner. As can be appreciated, the fourth substrate 36 is switched to the lens state, and the diffractive optical element 30 is in the diffractive state; alternatively, the fourth substrate 36 is switched to the diffusing state so that the diffractive optical element 30 is in the diffusing state; alternatively, a part of the fourth substrate 36 is switched to the transparent state and the other part is switched to the diffusive state, so that a part of the diffractive optical element 30 is switched to the diffractive state and the other part is switched to the diffusive state.

The fourth substrate 36 includes a third polymer base 361 and a plurality of third liquid crystal droplets 362, and the plurality of third liquid crystal droplets 362 are dispersed on the third polymer base 361. When the first conductive film 41 and the second conductive film 42 are electrified and the voltage is set at a preset value, the refractive index of the third polymer matrix 361 is the same as that of the third liquid crystal droplet 362, so that the fourth substrate 36 corresponding to the first conductive film 41 and the second conductive film 42 is in a transparent state, parallel light projected from the collimator lens 20 passes through the third substrate 35 in the transparent state, then passes through the diffraction beam expanding and copying functions of the second microstructure 34, and finally passes through the transparent fourth substrate 36 to be projected to an external target object in the form of structured light; at this time, the diffractive optical element 30 is in a diffractive state. When the first conductive film 41 and the second conductive film 42 are not energized, and the refractive index of the third polymer matrix 361 is different from the refractive index of the third liquid crystal droplet 362, the fourth substrate 36 corresponding to the first conductive film 41 and the second conductive film 42 is in a diffused state, and the parallel light projected from the collimator lens 20 firstly passes through the third substrate 35 in a transparent state, then passes through the second microstructure 34, and finally passes through the fourth substrate 36 in a diffused state, and is scattered under the diffusion effect of the fourth substrate 36 to form a bright infrared light, and finally is projected to an external target object; at this time, the diffractive optical element 30 is in a diffused state.

Through adopting above-mentioned technical scheme, make fourth base plate 36 adopt the material of polymer dispersed liquid crystal to make, then fourth base plate 36 just can switch into transparent state or diffusion state respectively through its self structure, with corresponding make diffractive optical element 30 switch into diffraction state or diffusion state, need not additionally to set up the optical element who is used for scattering the structured light for the pan infrared light, thus, the optical element's of projecting the module use has been reduced, the cost of manufacture of projecting the module has been saved, the volume of projecting the module has also been reduced simultaneously, help further realizing imaging device's miniaturized design.

It should be noted that, in the present embodiment, the fourth substrate 36 includes one diffraction region or includes a plurality of diffraction regions.

Alternatively, as shown in fig. 7, if the fourth substrate 36 includes one diffraction region, the first conductive film 41 and the second conductive film 42 on two opposite sides of the fourth substrate 36 along the first direction X are both provided as one, and an external voltage device adjusts the voltage between the first conductive film 41 and the second conductive film 42, so that the fourth substrate 36 is switched into the transparent state or the diffusion state under the action of different voltages, thereby enabling the imaging device to acquire an infrared image or a uniform infrared image of a band structure characteristic.

Alternatively, as shown in fig. 8, the fourth substrate 36 includes a plurality of the above-mentioned diffraction regions, the first conductive films 41 and the second conductive films 42 on the two opposite sides of the fourth substrate 36 in the first direction X are provided in plurality, the plurality of first conductive films 41 and the plurality of second conductive films 42 are provided in one-to-one correspondence, and the first conductive films 41 and the second conductive films 42 are provided on the two opposite sides of each diffraction region in the first direction X, so that an external voltage device can switch the diffraction region into the diffraction state or the diffusion state by individually controlling the voltage between the first conductive films 41 and the second conductive films 42 on the two opposite sides of each diffraction region. It will be appreciated that when it is desired to obtain an infrared map of the band structure characteristics, an external voltage device controls the voltage across all the diffractive regions on the fourth substrate 36, such that all the diffractive regions of the fourth substrate 36 are in a transparent state; when a uniform infrared image needs to be acquired, an external voltage device controls the voltage of all diffraction regions on the fourth substrate 36, so that all diffraction regions of the fourth substrate 36 are in a diffusion state; the external voltage device can also control part of the diffraction region to be switched to a transparent state, and the other part of the diffraction region to be switched to a diffusion state, so that an infrared image with both band structure characteristics and a uniform infrared image is obtained, and the variety of the infrared image is increased.

The rest of this embodiment is the same as the embodiment, and the unexplained features in this embodiment are explained by the embodiment two, which is not described again here.

Example four

Referring to fig. 1, fig. 2 and fig. 9, the present embodiment differs from the first, second and third embodiments in the specific structure of the diffractive optical element 30.

The diffractive optical element 30 in the present embodiment includes a body portion 37 and a diffuser portion (not shown). The main body 37 is provided on the light exit side of the collimator lens 20, and the main body 37 is a structure for diffracting light by the diffractive optical element 30; the main body 37 is in a transparent state. The diffusion part is polymer dispersed liquid crystal, and is arranged on the body part 37; the diffusion can be switched to a transparent state and/or a diffused state under the action of different voltages.

The main body 37 is used for diffraction. The diffusion part is used for being switched into a transparent state and/or a diffusion state under the action of different voltages; it is understood that the first conductive film 41 and the second conductive film 42 of the conductive film 40 are respectively disposed on opposite sides of the diffusion portion along the first direction X, and the diffusion portion is switched to the transparent state and/or the diffusion state by an external pressurizing device by controlling voltages of the first conductive film 41 and the second conductive film 42. Wherein the diffusion portion is switched to a transparent state so that the diffractive optical element 30 is in a diffractive state; alternatively, the diffusion portion is switched to the diffusion state so that the diffractive optical element 30 is in the diffusion state; alternatively, one part of the diffusion portion is switched to the transparent state and the other part is switched to the diffusion state, so that one part of the diffractive optical element 30 is switched to the diffractive state and the other part is switched to the diffusion state. When the first conductive film 41 and the second conductive film 42 are energized and the voltage is set at a preset value, the diffusion portion corresponding to the first conductive film 41 and the second conductive film 42 is switched to a transparent state, and then parallel light projected from the collimating mirror 20 passes through the diffusion portion and the body portion 37 in the transparent state, is subjected to diffraction beam expansion and replication, and is projected to an external target object in the form of structured light; at this time, the diffractive optical element 30 is in a diffractive state. When the first conductive film 41 and the second conductive film 42 are not energized, the diffusion portion corresponding to the first conductive film 41 and the second conductive film 42 is switched to the diffusion state, and then the parallel light projected from the collimator lens 20 is scattered to form the infrared light when passing through the diffusion portion in the diffusion state, and finally projected to the external target object; at this time, the diffractive optical element 30 is in a diffused state.

Wherein, the diffusion part is polymer dispersed liquid crystal, and the diffusion part comprises a polymer matrix and a plurality of liquid crystal droplets dispersedly arranged on the polymer matrix; under the action of different voltages, the diffusion part is switched into a transparent state and/or a diffusion state by adjusting the refractive index of the liquid crystal droplet of the diffusion part.

Through adopting above-mentioned technical scheme for diffraction optical element 30 can switch into diffusion state or diffraction state, then throws the module and has only set up a light source 10, can realize the projection work of structure light sum pan infrared light, like this, has saved the cost of manufacture who throws the module, has also reduced the volume of throwing the module simultaneously, helps imaging device's miniaturized design.

In one embodiment, referring to fig. 9, the main body 37 includes a third microstructure 371, and the third microstructure 371 is disposed on the light-emitting side of the collimating mirror 20.

A plurality of third grooves 3711 are formed in a side of the third microstructure 371 away from the collimating mirror 20, that is, a plurality of third grooves 3711 are formed in the light exit side of the third microstructure 371, and the plurality of third grooves 3711 are distributed at intervals; correspondingly, the light-emitting side of the third microstructure 371 is provided with a plurality of third protrusions 3712 distributed at intervals, and the third protrusions 3712 and the third grooves 3711 are arranged adjacently, so that the light-emitting side of the third microstructure 371 is in an uneven design; thus, the phase of the incident light is modulated by changing the optical path difference of the incident light, and the diffraction beam expanding and copying effects of the incident light are realized, so that the third microstructure 371 is used for performing the diffraction effect. The third microstructure 371 is the same as the first microstructure 31 and the second microstructure 34 in the above embodiments, except that: the third microstructure 371 is a structure in a transparent state and is used for diffraction.

The diffusion portion is disposed inside the third microstructure 371; alternatively, the diffusion portion is provided on one side of the third microstructure 371 in the first direction X. Since the diffusion portion can be switched to the transparent state or the diffusion state, the parallel light emitted from the collimator mirror 20 can pass through the diffusion portion in the transparent state or the diffusion portion in the diffusion state.

By adopting the above technical solution, the diffusion portion is integrated inside the third microstructure 371 or is disposed at one side of the third microstructure 371, and the diffusion portion can be switched to the transparent state and/or the diffusion state under the action of different voltages, so that the diffractive optical element 30 can be switched to the diffraction state and/or the diffusion state when the diffusion portion is switched to the state; moreover, the diffusion part is integrated inside the third microstructure 371, so that the integration level of the third microstructure 371 and the diffusion part is improved, and the volume of the projection module is further reduced; the diffusion portion is disposed on one side of the third microstructure 371, which helps to simplify the bonding process between the third microstructure 371 and the diffusion portion.

In one embodiment, referring to fig. 9, the main body 37 further includes a fifth substrate 372 and a sixth substrate 373, the collimating mirror 20, the fifth substrate 372 and the sixth substrate 373 are sequentially distributed along the first direction X, the fifth substrate 372 is disposed on the light-emitting side of the collimating mirror 20, and the third microstructure 371 is sandwiched between the fifth substrate 372 and the sixth substrate 373; in operation, the parallel light projected from the collimating mirror 20 passes through the fifth substrate 372, the third microstructure 371 and the sixth substrate 373 in sequence, and then is projected to an external target object. The fifth substrate 372 has the same structure as the first substrate 32 and the third substrate 35 in the above embodiment, and the sixth substrate 373 has the same structure as the second substrate 33 and the fourth substrate 36 in the above embodiment, except that: the fifth substrate 372 and the sixth substrate 373 are both in a transparent state, that is, the entire main body 37 of the diffractive optical element 30 is in a transparent state, and the material of the entire main body 37 is not polymer dispersed liquid crystal.

It should be noted that the fifth substrate 372 and the sixth substrate 373 protect the third microstructure 371.

Note that the diffusion portion is provided inside the fifth substrate 372, or the diffusion portion is provided inside the sixth substrate 373, or the diffusion portion is provided on the side of the fifth substrate 372 in the first direction X, or the diffusion portion is provided on the side of the sixth substrate 373 in the first direction X. By adopting the above technical solution, the diffusion portion can be disposed inside the fifth substrate 372, on the side of the fifth substrate 372, inside the sixth substrate 373, or on the side of the sixth substrate 373, so that the flexibility of the disposition of the diffusion portion is improved, which contributes to switching the diffractive optical element 30 between the diffractive state and the diffusion state.

In one embodiment, the diffusion portion has one diffraction region as described above, the first conductive film 41 and the second conductive film 42 on two opposite sides of the body portion 37 in the first direction X are both provided as one, and an external voltage device adjusts the voltage between the first conductive film 41 and the second conductive film 42, so that the diffusion portion is switched into a transparent state and/or a diffusion state under the action of different voltages, thereby enabling the imaging device to acquire an infrared image or a uniform infrared image of a band structure characteristic.

Alternatively, the diffusion portion is divided into a plurality of the above-described diffraction regions, the first conductive film 41 and the second conductive film 42 are respectively disposed on opposite sides of the diffusion portion in the first direction X, and each of the diffraction regions has the first conductive film 41 and the second conductive film 42 on opposite sides in the first direction X; in this way, the external voltage device switches each diffraction region to the diffraction state or the diffusion state by individually controlling the voltage between the first conductive film 41 and the second conductive film 42 on the opposite sides of each diffraction region.

EXAMPLE five

Referring to fig. 1 and 2, the present embodiment provides an imaging device, which includes an imaging module and a projection module, wherein the projection module is configured to project structural light and/or infrared light to an external target object, and the imaging module receives the structural light and/or infrared light projected by the projection module onto the target object, so as to identify the target object through the structural light and/or infrared light projected by the projection module, thereby imaging the target object. It should be noted that the infrared image of the target object acquired by the imaging module based on the structured light and/or the infrared-flashing light projected by the projection module is an infrared image of a structural feature, or a uniform infrared image, or both an area of the infrared image of the structural feature and an area of the uniform infrared image.

Wherein, the imaging module includes infrared camera and color camera, and infrared camera can acquire the infrared picture of taking the structural feature based on the structured light to can acquire even infrared picture based on the pan infrared light, and color camera is used for acquireing the colored drawing. Therefore, the imaging device provided by the embodiment has the function of acquiring the depth map, the uniform infrared image and the color map of the target object, and can be applied to the field of face brushing so as to effectively deal with the plane attack means.

Through adopting above-mentioned technical scheme, throw the module and only set up a light source 10, realized the work of throwing of structured light and pan infrared light promptly, like this, saved the cost of manufacture who throws the module, also reduced the volume of throwing the module simultaneously, helped imaging device's miniaturized design.

The rest of this embodiment is the same as the first, second, third, or fourth embodiment, and the unexplained features in this embodiment are explained in the first, second, third, or fourth embodiment, which is not described herein again.

EXAMPLE six

Referring to fig. 1 and fig. 2, the present embodiment provides an electronic device, which includes an electronic device body and an imaging device disposed on the electronic device body.

Through adopting above-mentioned technical scheme, throw the module and only set up a light source 10, realized the work of throwing of structured light and pan infrared light promptly, like this, saved the cost of manufacture who throws the module, also reduced the volume of throwing the module simultaneously, helped imaging device's miniaturized design to help electronic equipment's miniaturized design.

It should be noted that, by the concept of the above embodiment, the electronic device provided by the embodiment has the function of acquiring a depth map, a uniform infrared map and a color map of a target object, and can be applied to the field of face brushing to effectively cope with a plane attack means; the electronic device body provided in this embodiment may be, but is not limited to, a mobile phone, a tablet, or a notebook computer.

The rest of this embodiment is the same as the first, second, third, fourth, or fifth embodiment, and the unexplained features in this embodiment are explained in the first, second, third, fourth, or fifth embodiment, which is not described herein again.

The above description is only exemplary of the present application and should not be taken as limiting the present application, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A projection module, comprising:

a light source for projecting structured light;

2. The projection module of claim 1, wherein the diffractive optical element comprises a first microstructure disposed on the light exit side of the collimator, and a plurality of first grooves are disposed at intervals on a side of the first microstructure facing away from the collimator; the first microstructure is made of polymer dispersed liquid crystal and can be switched into a transparent state and/or a diffusion state under the action of different voltages.

3. The projection module of claim 2, wherein the diffractive optical element further comprises a transparent first substrate and a transparent second substrate, the first substrate and the second substrate are sequentially distributed along the light-emitting direction of the light source, and the first microstructure is sandwiched between the first substrate and the second substrate.

4. The projection module of claim 1, wherein the diffractive optical element comprises a third substrate, a fourth substrate, and a transparent second microstructure, the third substrate and the fourth substrate are sequentially distributed along the light-emitting direction of the light source, the third substrate is disposed on the light-emitting side of the collimating mirror, and the second microstructure is sandwiched between the third substrate and the fourth substrate; a plurality of second grooves distributed at intervals are formed in one side, away from the third substrate, of the second microstructure;

5. The projection module of claim 1 wherein the diffractive optical element comprises a body portion and a diffuser portion; the main body part is arranged on the light-emitting side of the collimating mirror to diffract the structured light projected from the collimating mirror; the diffusion part is polymer dispersed liquid crystal and is arranged on the body part; the diffusion portion can be switched to a transparent state and/or a diffusion state by different voltages.

6. The projection module of claim 5, wherein the body comprises a transparent third microstructure, the third microstructure is disposed on the light-emitting side of the collimating mirror, a plurality of third grooves are disposed on a side of the third microstructure facing away from the collimating mirror, and the diffusion portion is disposed inside the third microstructure or on a side of the third microstructure along the light-emitting direction of the light source.

7. The projection module of claim 6, wherein the main body further comprises a fifth transparent substrate and a sixth transparent substrate, the fifth and sixth substrates are sequentially distributed along a light emitting direction of the light source, and the third microstructure is sandwiched between the fifth and sixth substrates; the diffusion part is arranged in the fifth substrate, in the sixth substrate, on one side of the fifth substrate in the light emitting direction of the light source or on one side of the sixth substrate in the light emitting direction of the light source.

8. The projection module according to any of claims 1 to 7 wherein the diffractive optical element comprises a diffractive region which can be switched into a diffractive state or into a diffusive state under the action of different voltages;

9. An imaging device comprising an imaging module, and further comprising a projection module according to any one of claims 1 to 8, wherein the imaging module is configured to receive the light projected by the projection module to image a target object.

10. An electronic apparatus comprising an electronic apparatus body, further comprising the imaging device according to claim 9, the imaging device being provided on the electronic apparatus body.