TWM629985U - Polarization beam splitting module and four-beam polarization beam splitting system thereof - Google Patents

Abstract

This creation is about a polarization beam splitting module, which is used in an environment that receives a pulsed light. The polarization beam splitting module includes: a linear polarizer, a quarter-phase retarder, a beam splitter, an air layer, and a reflector , and the isolation layer. Among them, the linear polarizer is used to convert any beam into linearly polarized light, the quarter-phase retarder is used to convert linearly polarized light and circularly polarized light to each other, and the beam splitter is used to divide a beam of circularly polarized light into two Two left-handed (right-handed) circularly polarized lights with the same phase and light intensity and their traveling directions are perpendicular to each other. (Left-handed) circularly polarized light, the mirror is used to change the transmission direction of the beam, and the isolation layer is used to protect the polarization beam splitting module. The present creation further provides a four-beam polarization beam splitting system including the aforementioned polarization beam splitting module.

Description

Polarization beam splitting module and its four-beam polarization beam splitting system

This creation is about a polarization beam splitting module, especially a four-beam polarization beam splitting system that can be realized by simple processing through the polarization beam splitting module.

With the evolution of ranging technology, various ranging technologies are continuously developed, and are widely used in, for example, vehicle distance detection, face recognition, and various Internet-of-Things (IoT) devices. Common ranging technologies are, for example, infrared ranging (Infrared Radiation, IR) technology, ultrasonic (Ultrasound) ranging technology, and pulsed light (Intense Pulsed Light, IPL) ranging technology. However, with the increasing accuracy requirements of ranging, the pulsed light ranging technology using the Time-of-Flight (ToF) measurement method is one of the main research directions in this field.

The time-of-flight measurement method is an active 3D scanning technology that has been frequently used in recent years, mainly due to its large measurable distance range, high resolution and low software complexity, which is conducive to market expansion and technology development. The sensing technology of the time-of-fly ranging method is to add another sensing element capable of measuring depth information to the traditional image sensor. This element calculates the depth information by sensing the time change of light reflection and reception.

For now, the light source in the conventional time-of-flight ranging method generally uses non-polarized light. In recent years, a sensing technology using polarized light has been gradually developed, but two light sources and multiple polarized light must be used. The reason is that the two polarized light sources with orthogonal polarizations are not disturbed by ambient light when received by the light sensor, so that clearer depth information can be obtained.

However, as smart hands become thinner and thinner, the number of components that can be placed in the interior space of smartphones will decrease accordingly. Therefore, how to reduce the internal components of smartphones and the usage space occupied by components should be solved by R&D personnel. one of the problems.

Therefore, the creator of this case came to this creation after observing the above-mentioned needs.

The purpose of this creation is to provide a polarization beam splitting module, which can realize the function of simultaneously completing the excitation light of multiple different polarization directions through simple processing and combination, thereby simplifying and miniaturizing the polarization beam splitting system. , which further improves its technical performance and reliability, and has extremely important practical significance in the fields of optical testing, optical modulation, optical ranging and other application technologies.

Another purpose of the present creation is to provide a four-beam polarization beam splitting system, which can realize excitation light of four different polarization directions through simple processing and combination of polarization beam splitting modules, and it requires at least two light sources to generate complex numbers The ranging sensing technology that can only be performed by a polarized light source is reduced to only one light source and the polarization direction of the excitation light can be adjusted by itself to perform the calculation of the ToF sensing technology, which greatly reduces the cost and increases the stability of the system.

In order to achieve the above-mentioned purpose, the present invention provides a polarization beam splitting system, which is applied in an environment that receives a pulsed light. The polarization beam splitter module includes: a linear polarizer, which is used to convert the pulsed light into linearly polarized light. ; a quarter-phase retarder, which is arranged on the linear polarizer; a beam splitter, which is arranged on the quarter-phase retarder, the beam splitter has an incident surface, a first light-emitting surface, and a second light-emitting surface; an air layer, which is arranged on the quarter-phase retarder, and is coupled to the second light-emitting surface; a reflection mirror, which is arranged on the quarter-phase retarder and coupled to the second light-emitting surface, the reflector is used to reflect the light beam, thereby changing the transmission direction of the light beam, and changing the rotation direction of the circularly polarized light; and an isolation layer, which is arranged on the beam splitter mirror and the reflecting mirror; wherein, the pulsed light is converted into a linearly polarized light with a preset polarization direction after passing through the linear polarizer, and the linearly polarized light with a preset polarization direction passes through the quarter A phase retarder is converted into a circularly polarized light with a first polarization direction, the circularly polarized light with a first polarization direction enters the beam splitter from the incident surface, and the beam splitter outputs from the first light exit surface The circularly polarized light with the first polarization direction transmitted in a first direction is sent to the isolation layer, and the beam splitter outputs the circularly polarized light with the first polarization direction transmitted in a second direction from the second light exit surface the circularly polarized light, the circularly polarized light with the first polarization direction passes through the air layer to the reflector and is reflected, and changes the polarization direction to form a circularly polarized light with a second polarization direction, The circularly polarized light having the second polarization direction is diverted from being transmitted along the second direction to the isolation layer along the first direction.

Preferably, according to the polarization beam splitting module of the present invention, the linear polarizer is a metal grating.

Preferably, according to the polarization beam splitting module of the present invention, the first direction is orthogonal to the second direction.

Preferably, according to the polarization beam splitting module of the present invention, the wavelength of the pulsed light is between 780nm and 1400nm.

Also, in order to achieve the above-mentioned purpose, the present creation is based on the above-mentioned polarization beam splitting module, and further provides a four-beam polarization beam splitting system, which includes: a first polarization beam splitting module, which is used to receive the pulsed light, The first polarizing beam splitting module includes the above-mentioned polarizing beam splitting module and a first quarter-phase retarder, the first quarter-phase retarder is disposed on the isolation layer and covers the beam splitter, the first quarter-phase retarder A quarter-phase retarder is used to convert circularly polarized light into linearly polarized light; a second polarized light splitting module is coupled to the first polarized light splitting module, and the second polarized light splitting module includes The above-mentioned polarization beam splitting module and a second quarter phase retardation plate, the second quarter phase retardation plate is arranged on the isolation layer and covers the beam splitter and the reflection mirror, the second quarter phase retardation plate A phase retarder is used to convert circularly polarized light into linearly polarized light; and a third polarized light splitting module is coupled to the first polarized light splitting module, and the third polarized light splitting module includes the above-mentioned polarized light a light splitting module; wherein, after the first polarized light splitting module receives the pulsed light, the first polarized light splitting module outputs the linearly polarized light with a preset polarization direction to the second polarized light splitting module, and the The first polarized light splitting module outputs the circularly polarized light in the second polarization direction to the third polarized light splitting module, and after the second polarized light splitting module receives the linearly polarized light with the preset polarization direction, the The second polarization beam splitting module outputs the linearly polarized light with the preset polarization direction and a linearly polarized light with a third polarization direction, and the third polarization beam splitting module receives the circular polarization in the second polarization direction After polarized light, the third polarized light splitting module outputs the circularly polarized light with the first polarization direction and a polarized light with a fourth polarization direction.

Preferably, according to the four-beam polarization beam splitting system of the present invention, the predetermined polarization direction and the third polarization direction are orthogonal to each other.

Preferably, according to the four-beam polarization beam splitting system of the present invention, the third polarization beam splitting module further comprises a polarizing layer, the polarizing layer is disposed on the isolation layer, and the polarizing layer is used for converting the circularly polarized light. is linearly polarized light.

Preferably, according to the four-beam polarization beam splitting system of the present invention, the difference between the preset polarization direction and the fourth polarization direction is 45 degrees.

Therefore, the present invention provides a polarization beam splitting module, which can realize the function of simultaneously completing the excitation light of multiple different polarization directions through simple processing and combination, thereby simplifying and miniaturizing the polarization beam splitting system. , which further improves its technical performance and reliability, and has extremely important practical significance in the fields of optical testing, optical modulation, optical ranging and other application technologies. In addition, the linear polarizer and quarter-phase retarder of the polarization beam splitting module can use birefringent polarizers. It is less likely to change under the irradiation of laser, which can prevent heat accumulation after long-term high-energy laser irradiation, and prevent problems such as deformation and deterioration.

In order to make those skilled in the art understand the purpose, features and effects of the creation, the following specific examples are used to describe the creation in detail with the accompanying drawings.

The inventive concept will now be explained more fully hereinafter with reference to the accompanying drawings in which exemplary embodiments of the inventive concept are shown. Advantages and features of the inventive concept and methods for achieving the same will be apparent from the following exemplary embodiments, which are set forth in more detail with reference to the accompanying drawings. However, it should be noted that the present inventive concept is not limited to the following exemplary embodiments, but may be implemented in various forms. Accordingly, the exemplary embodiments are provided merely to disclose the inventive concept and to familiarize those skilled in the art with the class of the inventive concept. In the drawings, exemplary embodiments of the inventive concepts are not limited to the specific examples provided herein and are exaggerated for clarity.

The terminology used herein is used to describe particular embodiments only, and is not intended to limit the present invention. As used herein, the singular terms "a" and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may be present.

Similarly, it will be understood that when an element (eg, a layer, region, or substrate) is referred to as being "on" another element, it can be directly on the other element or intervening elements may be present. In contrast, the term "directly" means that no intervening elements are present. It should be further understood that when the terms "comprising" and "comprising" are used herein, it is intended to indicate the presence of stated features, integers, steps, operations, elements, and/or components, but does not exclude one or more other features , integers, steps, operations, elements, components, and/or the presence or addition of groups thereof.

Furthermore, exemplary embodiments in the detailed description are illustrated in cross-section illustrations that are idealized exemplary illustrations of the present inventive concepts. Accordingly, the shapes of the exemplary figures may be modified according to manufacturing techniques and/or tolerable errors. Therefore, the exemplary embodiments of the present inventive concept are not limited to the specific shapes shown in the exemplary figures, but may include other shapes that may be produced according to the manufacturing process. The regions illustrated in the figures have general characteristics and are used to illustrate specific shapes of elements. Therefore, this should not be considered limited to the scope of this creative concept.

It will also be understood that, although the terms "first," "second," "third," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish each element. Thus, a first element in some embodiments could be termed a second element in other embodiments without departing from the teachings of the present creation. Exemplary embodiments of aspects of the present inventive concept illustrated and described herein include their complementary counterparts. Throughout this specification, the same reference numbers or the same designators refer to the same elements.

Furthermore, example embodiments are described herein with reference to cross-sectional and/or plan views, which are illustrations of idealized example illustrations. Accordingly, deviations from the shapes shown, for example, caused by manufacturing techniques and/or tolerances, are expected. Accordingly, the exemplary embodiments should not be considered limited to the shapes of the regions shown herein, but are intended to include deviations in shapes resulting from, for example, manufacturing. Thus, the regions illustrated in the figures are schematic and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of example embodiments.

Please refer to Figures 1-3, Figure 1 is a block diagram of the polarization beam splitter module according to the present creation; Figure 2 is a schematic diagram of the specific details of the polarization beam splitter module according to the present creation; Figure 3 illustrates the polarization beam splitter module reception of the present creation Schematic diagram of incident light from the external environment. As shown in FIG. 1 , the polarization beam splitting module 100 according to the present invention is applied in the environment in which the pulsed light Lp is received. The polarization beam splitting module 100 includes: a linear polarizer 11 , a quarter-phase retarder 12 , The beam splitter 13 , the reflection mirror 14 , the isolation layer 15 , and the air layer 16 .

Specifically, as shown in FIG. 1 and FIG. 2 , the linear polarizer 11 according to the present invention is used to convert any light beam into linearly polarized light L, wherein the linear polarizer 11 converts the incident pulsed light Lp into Linearly polarized light L with a preset polarization direction D. Specifically, in some embodiments, the linear polarizer 11 is a metal grating. For example, the linear polarizer 11 can use a complementary metal grating structure to make a half-wave plate in the megahertz band, which will have capacitive The inductive metal meshes are stacked mutually perpendicular to each other, so that the electric field components of the incident pulsed light Lp along these two directions undergo different phase changes, thereby changing the polarization state of the pulsed light Lp. Specifically, as shown in FIG. 3 , in some embodiments, the wavelength range of the pulsed light Lp is the infrared light wavelength range. More specifically, the wavelength range of the pulsed light Lp is between 780 nm and 1400 nm. And the linear polarizer 11 converts the incident pulsed light Lp into the horizontal linearly polarized light L1 , wherein the predetermined polarization direction D is the horizontal polarization direction, but the present invention is not limited to this.

Specifically, as shown in FIG. 1 and FIG. 2 , the quarter-phase retardation plate 12 according to the present invention is disposed on the linear polarizer 11 , and the quarter-phase retardation plate 12 is used to convert the linearly polarized light L Converted into circularly polarized light Lc, wherein the quarter-phase retarder 12 converts the linearly polarized light L with a predetermined polarization direction D into a circularly polarized light Lc with a first polarization direction D1. Specifically, in some embodiments, quarter retarder 12 may be one of reflective, dichroic, and birefringent polarizers. Preferably, the quarter-phase retarder 12 can use birefringent crystals. The advantage of using birefringent crystals is that compared with other polarizers, birefringent crystals are less likely to change under the irradiation of high-energy lasers, so as to achieve long-term prevention. The effect of heat accumulation after time high-energy laser irradiation causes problems such as deformation and deterioration. Therefore, the quarter-phase retarder 12 according to the present invention can use a birefringent crystal to convert the linearly polarized light L into the circularly polarized light Lc. Specifically, as shown in FIG. 3 , in this embodiment, the quarter phase retarder 12 may be a quarter wave plate (QWP), so that the horizontal linearly polarized light L1 is incident to the quarter wave plate After one phase retarder 12, a quarter phase retarder 12 converts the horizontal linearly polarized light L1 into a right-handed polarized light Lcr, wherein the first polarization direction D1 is the right-handed polarization direction, but This creation is not limited to this.

Specifically, as shown in FIG. 1 and FIG. 2 , the beam splitter 13 according to the present invention is disposed on the quarter-phase retarder 12 , and the beam splitter 13 has an incident surface 131 , a first light exit surface 132 , and The second light exit surface 133, wherein the circularly polarized light Lc with the first polarization direction D1 enters the beam splitter 13 from the incident surface 131, and the beam splitter 13 outputs the light beam with the first light output along the first direction X from the first light exit surface 132. A circularly polarized light Lc in a polarization direction D1 reaches the isolation layer 15, and the beam splitter 13 outputs a circularly polarized light Lc with a first polarization direction D1 transmitted along the second direction Y from the second light emitting surface 133. Specifically, in some embodiments, the beam splitter 13 may be a birefringent polarizer made of natural calcite crystal, which adopts a double-reflection structure design, and uses the total internal double reflection of the incident light on the crystal interface to change the polarization. The polarization direction and beam splitting can be achieved through the beam splitter 13 to complete the integration of various functions such as changing the polarization direction, beam splitting and beam steering. Specifically, as shown in FIG. 3 , in some embodiments, the right-handed polarized light Lcr is converted into the right-handed polarized light Lcr transmitted along the first direction X through the beam splitter 13 to the isolation layer 15 , and along the second direction The right-handed polarized light Lcr transmitted by Y is transmitted to the air layer 16, but the present invention is not limited thereto.

Specifically, as shown in FIG. 1 and FIG. 2 , the air layer 16 according to the present invention is disposed on the quarter-phase retarder 12 and coupled to the second light emitting surface 133 . Specifically, in some embodiments, the refractive index of the air layer 16 is smaller than the refractive index of the reflector 14 , so that the air layer 16 is an optically rarer medium relative to the reflector 14 , so that the light beam is transmitted from the air layer 16 to the reflector 14 . The polarization direction is changed, and the reflected light orthogonal to the original beam polarization direction is formed.

Specifically, as shown in FIG. 1 and FIG. 2 , the reflector 14 according to the present invention is disposed on the quarter-phase retarder 12 and coupled to the second light emitting surface 133 , and the reflector 14 is used to make The beam is reflected, which in turn changes the direction of transmission of the beam. Specifically, please refer to FIG. 2 and FIG. 3 , in some embodiments, after the right-handed polarized light Lcr transmitted in the second direction Y is transmitted to the mirror 14 , the light Lcr transmitted in the second direction Y with the second polarization is formed. The circularly polarized light Lc in the polarization direction D2, wherein the second polarization direction D2 is the left-handed polarization direction, so that the right-handed polarized light Lcr originally transmitted in the second direction Y is converted into a left-handed polarized light Lcr transmitted in the first direction X The polarized light Lcl reaches the isolation layer 15 . Specifically, in some embodiments, the first polarization direction D1 and the second polarization direction D2 are orthogonal to each other, but the present invention is not limited thereto.

Specifically, as shown in FIGS. 1 and 2 , the isolation layer 15 according to the present invention is disposed on the uppermost layer of the polarization beam splitting module 100 . More specifically, when there are plural polarization beam splitting modules 100 , they are provided between the polarization beam splitting modules 100 . Therefore, the isolation layer 15 may serve as an isolation structure between the complex polarization beam splitting modules 100 in some embodiments. In this creation, the word "isolation" covers both electrical isolation and physical isolation. The isolation layer 15 may be a single layer of inorganic encapsulation material, a multi-layer stack of inorganic encapsulation materials, or a stack of pairs of inorganic encapsulation materials and organic encapsulation materials. The inorganic encapsulating material used is, for example, but not limited to, silicon nitride (SiNx), silicon oxide (SiOx), silicon oxynitride (SiONx), aluminum oxide (AlOx), or titanium oxide (TiOx).

It is worth mentioning that the isolation layer 15 of the polarizing beam splitting module 100 according to the present invention can be directly used as the substrate of other polarizers, without the need for additional substrates, and the user can directly perform simple processing on the isolation layer 15. The excitation light of different polarization directions enables the present invention to realize the thinning of the polarization beam splitting module 100, and at the same time, it has wide applicability.

Therefore, the present invention provides a polarization beam splitting module 100, which can realize the function of simultaneously completing the excitation light of multiple different polarization directions through simple processing and combination, thereby simplifying the polarization beam splitting system and improving the efficiency of the polarization beam splitting system. Thinning further improves its technical performance and reliability, and has extremely important practical significance in the fields of optical testing, optical modulation, optical ranging and other application technologies. In addition, the linear polarizer 11 and the quarter-phase retarder 12 of the polarization beam splitting module 100 are less likely to change under the irradiation of high-energy lasers by using birefringent polarizers, so as to prevent long-term high-energy laser irradiation. The effect of preventing the problem of deformation, deterioration, etc. after the heat accumulation.

Other examples of polarized light splitting modules are provided below, so that those with ordinary knowledge in the technical field to which this creation belongs can more clearly understand possible changes. Elements denoted by the same reference numerals as the above-mentioned embodiments are substantially the same as those described above with reference to FIG. 1 and FIG. 2 . The same elements, features, and advantages as those of the polarization beam splitting module 100 will not be described again.

Please refer to FIG. 4 , which illustrates an exemplary first polarization beam splitting module 100A. The difference between the first polarization beam splitting module 100A and the polarization beam splitting module 100 is that the first polarization beam splitting module 100A is further provided with a first quarter-phase retarder 121 . 121 is disposed on the isolation layer 15A and covers the beam splitter 13A, and the first quarter-phase retarder 121 is used to convert circularly polarized light to linearly polarized light. Specifically, in some embodiments, after the first polarization beam splitting module 100A receives the pulsed light Lp, the first polarization beam splitting module 100A outputs linearly polarized light with a preset polarization direction D and a second polarization direction D2 wherein, the linearly polarized light in the preset polarization direction D is the horizontal linearly polarized light L1, and the circularly polarized light in the second polarization direction D2 is the left-handed polarized light Lcl, but this creation is not limited to this.

Please refer to FIG. 5 , which illustrates an exemplary second polarization beam splitting module 100B. The difference between the second polarization beam splitting module 100B and the polarization beam splitting module 100 is that the second polarization beam splitting module 100B is further provided with a second quarter phase retarder 122 , a second quarter phase retarder 122 Disposed on the isolation layer 15B and encompassing the beam splitter 13B and the mirror 14B, the second quarter-phase retarder 122 is used to convert circularly polarized light to linearly polarized light. Specifically, in some embodiments, after the second polarization beam splitting module 100B receives the linearly polarized light with the preset polarization direction D, the second polarization beam splitter module 100B outputs the linearly polarized light with the preset polarization direction D Light and linearly polarized light with a third polarization direction D3, wherein the quarter-phase retarder 12B can be a quarter-wave plate, and the polarization direction D and the third polarization direction D3 are mutually positive. In this way, the linearly polarized light in the polarization direction D is the horizontal linearly polarized light L1, and the linearly polarized light in the third polarization direction D3 is the vertical linearly polarized light L2, but this creation is not limited to this.

It should be further noted that, compared with the polarization beam splitting module 100, the beam splitter 13B and the reflecting mirror 14B of the second polarization beam splitting module 100B and the beam splitter 13 and the reflecting mirror 14 of the polarization beam splitting module 100 are mirror-symmetrical, resulting in a mirror image. The symmetrical way can be simply by flipping the polarization beam splitting module 100 horizontally by 180 degrees, and then disposing the second quarter-phase retarder 122 on the isolation layer 15B to generate the second polarization beam splitting module 100B. However, the present invention is not limited to this.

Please refer to FIG. 6 , which illustrates an exemplary polarization beam splitting module 100C. The difference between the third polarization beam splitting module 100C and the polarization beam splitting module 100 is that the third polarization beam splitting module 100C is further provided with a polarizing layer 17, and the polarizing layer 17 is disposed on the isolation layer 15C and covers the reflecting mirror 14C. The polarizing layer Series 17 is used to convert circularly polarized light to linearly polarized light. Specifically, in some embodiments, after the third polarization beam splitting module 100C receives the circularly polarized light in the second polarization direction D2, the third polarization beam splitter module 100C outputs the circularly polarized light with the first polarization direction D1 And the linearly polarized light with the fourth polarization direction D4, wherein, the circularly polarized light in the first polarization direction D1 is the right-handed polarized light Lcr, and the polarizing layer 17 can be the polarizer of any polarization direction, In this embodiment, the difference between the fourth polarization direction D4 and the preset polarization direction D is 45 degrees. However, the linearly polarized light in the fourth polarization direction D4 may be linearly polarized light with any polarization angle, No special restriction is required.

It can be understood that those with ordinary knowledge in the technical field to which the present creation belongs can make various changes and adjustments based on the above examples, which will not be listed one by one here. The following will focus on applying the four-beam polarization beam splitting system according to the embodiment.

Please refer to FIG. 7 , which illustrates an exemplary four-beam polarization beam splitting system 10 . As shown in FIG. 6 , according to the four-beam polarization beam splitting system 10 of the present invention, which applies the above-mentioned embodiments, the four-beam polarization beam splitting system 10 includes: a first polarization beam splitting module 100A, a second polarization beam splitting module 100B , and the third polarization beam splitting module 100C.

In order to further understand the structural characteristics of this creation, the use of technical means and the expected effect, the actual execution process of this creation is described here. I believe that this will give you a more in-depth and specific understanding of this creation, as follows:

Specifically, please refer to FIG. 7 , the actual light splitting process of the four-beam polarized light splitting system 10 according to the present invention is described as follows: First, the first polarized light splitting module 100A receives the pulsed light Lp, and the first polarized light splitting module 100A outputs the horizontal linear polarization The light L1 goes to the second polarized light splitting module 100B, and the first polarized light splitting module 100A outputs the left-handed polarized light L1 to the third polarized light splitting module 100C; then, the second polarized light splitting module 100B receives the horizontal linearly polarized light L1, the second The polarization beam splitting module 100B outputs the horizontal linearly polarized light L1 with the preset polarization direction D and the vertical linear polarized light L2 with the third polarization direction D3; at the same time, the third polarization beam splitting module 100C receives the left-handed polarized light L11 , the third polarization beam splitting module 100C outputs the right-handed polarized light Lcr with the first polarization direction D1 and the linearly polarized light with the fourth polarization direction D4.

In this way, through the simple processing and combination of the polarization beam splitting module 100, excitation light in four different polarization directions can be realized in the present invention, and the ranging sensing technology that originally requires at least two light sources to generate complex polarization light sources can be implemented. It is reduced to only one light source and the polarization direction of the excitation light can be adjusted by itself to perform the calculation of the ToF sensing technology, which greatly reduces the cost and increases the stability of the system.

It is worth mentioning that, according to the four-beam polarization beam splitting system 10 of the present creation, the polarization beam splitting module 100 can be processed and combined in different ways, so as to realize excitation light in four different polarization directions. The polarization direction of the output polarized light can be adjusted according to user needs. For example, when the third polarization beam splitting module 100C is not provided with the polarizing layer 17, the polarized light output by the four-beam polarization beam splitting system 10 will be horizontal linear polarization. Light L1, vertically linearly polarized light L2, right-handed polarized light Lcr, and left-handed polarized light Lcl. In addition, when more polarization beam splitting modules 100 are processed and combined differently, the polarization beam splitting module 100 of the present invention can realize a six-beam polarization beam splitting system or an eight-beam polarization beam splitting system. Those with ordinary knowledge can make various changes and adjustments based on the above examples, which will not be listed one by one here.

Finally, the technical features of this creation and its achievable technical effects are summarized as follows:

First, the present invention provides a polarization beam splitting module 100, which can realize the function of simultaneously completing the excitation light of multiple different polarization directions through simple processing and combination, thereby simplifying the polarization beam splitting system. Thinning further improves its technical performance and reliability, and has extremely important practical significance in the fields of optical testing, optical modulation, optical ranging and other application technologies.

Second, by using birefringent polarizers, the linear polarizer 11 and the quarter-phase retarder 12 of the polarizing beam splitting module 100 according to the present invention are less likely to change under the irradiation of high-energy lasers, thereby achieving long-term prevention. The heat accumulation after time high-energy laser irradiation prevents deformation, deterioration and other problems.

Thirdly, through simple processing and combination of the polarization beam splitting module 100, excitation light in four different polarization directions can be realized in this creation, and the ranging sensing technology that originally requires at least two light sources to generate complex polarization light sources can be implemented. It is reduced to only one light source and the polarization direction of the excitation light can be adjusted by itself to perform the calculation of the ToF sensing technology, which greatly reduces the cost and increases the stability of the system.

The above describes the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

The above descriptions are only preferred embodiments of this creation, and are not intended to limit the scope of this creation; all other equivalent changes or modifications that have been completed without departing from the spirit disclosed in this creation shall be included in the following patent scope Inside.

100, 100A, 100B, 100C: Polarization beam splitter module 11, 11A, 11B, 11C: Linear polarizer 12, 12A, 12B, 12C: quarter phase retarder 121: The first quarter phase retarder 122: Second quarter phase retarder 13, 13A, 13B, 13C: Beamsplitters 131: Incident Surface 132: The first light-emitting surface 133: The second light-emitting surface 14, 14A, 14B, 14C: Reflector 15, 15A, 15B, 15C: isolation layer 16: Air layer 17: polarizing layer A: Default polarization direction A1: The first polarization direction A2: The second polarization direction A3: The third polarization direction A4: Fourth polarization direction L: Linearly polarized light Lc: circularly polarized light Lcl: Left-handed polarized light Lcr: right-handed polarized light PL: Pulsed Light X: first direction Y: the second direction

Fig. 1 is the block diagram of the polarization beam splitting module according to the present creation; 2 is a schematic diagram of the specific details of the polarization beam splitting module according to the present creation; 3 is a schematic diagram illustrating that the polarization beam splitting module of the present invention receives incident light from the external environment; 4 to 6 are schematic diagrams of various other exemplary polarization beam splitting modules, respectively; FIG. 7 is a schematic diagram of an exemplary four-beam polarization splitting system.

100: Polarization beam splitter module

11: Linear polarizer

12: Quarter phase retarder

13: Beamsplitter

14: Reflector

15: isolation layer

16: Air layer

Claims (8)

A polarization beam splitting module, which is applied in an environment for receiving a pulsed light, includes: A linear polarizer for converting the pulsed light into linearly polarized light; a quarter-phase retarder, which is arranged on the linear polarizer; a beam splitter, which is arranged on the quarter-phase retarder and has an incident surface, a first light-emitting surface, and a second light-emitting surface; an air layer disposed on the quarter-phase retarder and coupled to the second light-emitting surface; a mirror, which is disposed on the quarter-phase retarder and coupled to the air layer, and is used for reflecting the light beam, thereby changing the transmission direction of the light beam and changing the rotation direction of the circularly polarized light; and an isolation layer, which is arranged on the beam splitter and the reflector; Wherein, the pulsed light is converted into a linearly polarized light with a preset polarization direction after passing through the linear polarizer, and the linearly polarized light with a preset polarization direction is converted into a linearly polarized light through the quarter-phase retarder The circularly polarized light with the first polarization direction enters the beam splitter from the incident surface, and the beam splitter outputs the light transmitted along a first direction from the first light exit surface. The circularly polarized light with the first polarization direction is sent to the isolation layer, and the beam splitter outputs the circularly polarized light with the first polarization direction from the second light emitting surface along a second direction, which has The circularly polarized light in the first polarization direction passes through the air layer to the reflector and is reflected, and changes the polarization direction to form a circularly polarized light with a second polarization direction, which has a second polarization direction. Direction of circularly polarized light is turned from being transmitted along the second direction to being along the first direction to the isolation layer. The polarization beam splitting module according to claim 1, wherein the linear polarizer is a metal grating. The polarization beam splitting module of claim 1, wherein the first direction is orthogonal to the second direction. The polarization beam splitting module according to claim 1, wherein the wavelength of the pulsed light is between 780 nm and 1400 nm. A four-beam polarization beam splitting system includes: A first polarization beam splitting module for receiving the pulsed light, the first polarization beam splitting module includes the polarization beam splitting module as described in claim 1 and a first quarter phase retarder, the first polarization beam splitting module A quarter-phase retarder is disposed on the isolation layer and covers the beam splitter, and the first quarter-phase retarder is used to convert circularly polarized light into linearly polarized light; A second polarization beam splitting module, which is coupled to the first polarization beam splitting module, the second polarization beam splitting module includes the polarization beam splitting module according to claim 1 and a second quarter phase retardation The second quarter-phase retarder is arranged on the isolation layer and covers the beam splitter and the reflector, and the second quarter-phase retarder is used to convert circularly polarized light into linearly polarized light ;as well as a third polarization beam splitting module, which is coupled to the first polarization beam splitting module, and the third polarization beam splitting module includes the polarization beam splitting module according to claim 1; Wherein, after the first polarized light splitting module receives the pulsed light, the first polarized light splitting module outputs the linearly polarized light with a preset polarization direction to the second polarized light splitting module, and the first polarized light splitting module The module outputs the circularly polarized light in the second polarization direction to the third polarization beam splitting module, and after the second polarization beam splitting module receives the linearly polarized light with the preset polarization direction, the second polarization beam splits The module outputs the linearly polarized light with a preset polarization direction and a linearly polarized light with a third polarization direction, and the third polarization beam splitting module receives the circularly polarized light with the second polarization direction, The third polarization beam splitting module outputs the circularly polarized light with the first polarization direction and the polarized light with the fourth polarization direction. The four-beam polarization beam splitting system according to claim 5, wherein the preset polarization direction and the third polarization direction are orthogonal to each other. The four-beam polarization beam splitting system according to claim 5, wherein the third polarization beam splitting module further comprises a polarizing layer, the polarizing layer is disposed on the isolation layer, and the polarizing layer is used to convert the circularly polarized light into Linearly polarized light. The four-beam polarization beam splitting system of claim 7, wherein a difference between the preset polarization direction and the fourth polarization direction is 45 degrees.

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