TWI778262B - Tunable light projector - Google Patents

Abstract

A tunable light projector including a light source, a fixed optical phase modulator, a tunable liquid crystal panel, and a driver is provided. The light source is configured to emit a light beam. The fixed optical phase modulator is disposed on a path of the light beam and configured to modulate phases of the light beam. The tunable liquid crystal panel is disposed on the path of the light beam and configured to switch the light beam between a structured light and a flood light. The driver is electrically connected to a first electrode layer and a second electrode layer of the tunable liquid crystal panel and configured to change a voltage difference between the first electrode layer and the second electrode layer, so as to switch the light beam between the structured light and the flood light.

Description

Adjustable light projector

The present invention relates to a sensing device and a light projector, and more particularly, to an optical sensing device, a structured light projector and an adjustable light projector.

At present, the mainstream technologies of 3D sensing are divided into time of flight (TOF) and structured illumination (structured illumination). TOF technology uses a pulsed laser and a complementary metal-oxide-semiconductor (CMOS) sensor to measure light reflection time and convert it into distance. Due to cost and structure, it is generally more suitable for long-distance object analysis. In structured light technology, an IR source (IR source) is projected onto a diffractive optical element (DOE) to generate a two-dimensional diffraction pattern, and a sensor is used to collect the reflected light. The three-dimensional distance of an object can be converted using trigonometry. Structured light technology is limited by a projection lens with a fixed focal length, so the distance at which the diffraction pattern can be clearly imaged is also limited, and ultimately the distance of the object that can be resolved is limited to a small range.

In order to solve the above-mentioned problems of the structured light technology, some people propose a system in which an apodized lens is added to the lens group to generate multiple focal lengths. However, this approach sacrifices optical efficiency as well as the number and resolution of the 2D diffraction pattern.

In addition, in the 3D face recognition of the mobile device, both the flood light system and the structured light system are used to achieve the 3D face recognition. The floodlight system is first used to determine whether the approaching object is a human face. If the approaching object is a human face, the structured light system is then activated and used to determine whether the detected face is the user of the mobile device s face. However, using two systems simultaneously (ie, the flood light system and the structured light system) in one mobile device takes up a lot of space and is expensive.

The present invention provides an optical sensing device using liquid crystal to control the focus of structured light.

The invention provides a structured light projector which utilizes liquid crystal to control the focusing of structured light.

The present invention provides an adjustable light projector, which utilizes an adjustable liquid crystal panel to switch light beams between structured light and flood light.

An embodiment of the present invention provides an optical sensing device suitable for detecting an object or a feature of the object. The optical sensing device includes a structured light projector and a sensor. The structured light projector is used for projecting a structured light to the object. The structured light projector includes a light source, a diffractive optical element and a liquid crystal lens module. The light source is used for emitting a light beam. The diffractive optical element is disposed on the path of the light beam, and is used to generate a diffractive pattern to form structured light. The liquid crystal lens module is disposed on at least one of the path of the light beam and the path of the structured light, and can control the focus between at least two focus states. The sensor is adjacent to the structured light projector for sensing a reflected light. The reflected light is structured light body reflection.

An embodiment of the present invention provides a structured light projector. The structured light projector includes a light source, a diffractive optical element and a liquid crystal lens module. The light source is used for emitting a light beam. The diffractive optical element is disposed on the path of the light beam, and is used to generate a diffractive pattern to form structured light. The liquid crystal lens module is disposed on at least one of the path of the light beam and the path of the structured light, and can control the focus between at least two focus states.

An embodiment of the present invention provides an adjustable light projector, which includes a light source, a fixed optical phase modulator, an adjustable liquid crystal panel, and a driver. The light source is used for emitting a light beam. The fixed optical phase modulator is arranged on the path of the light beam and is used to modulate the phase of the light beam. The adjustable liquid crystal panel is arranged on the path of the light beam, and is used for switching the light beam between a structured light and a flood light. The adjustable liquid crystal panel includes a first substrate, a second substrate, a liquid crystal layer, a first electrode layer and a second electrode layer. The liquid crystal layer is disposed between the first substrate and the second substrate. At least one of the first electrode layer and the second electrode layer is a patterned layer. Both the first electrode layer and the second electrode layer are disposed on one of the first substrate and the second substrate, or are respectively disposed on the first substrate and the second substrate. The driver is electrically connected to the first electrode layer and the second electrode layer, and is used for changing the voltage difference between the first electrode layer and the second electrode layer, so as to switch the light beam between structured light and flood light.

Based on the above, the structured light projector according to the embodiment of the present invention includes at least one liquid crystal lens module with adjustable zoom. Providing a liquid crystal lens module with adjustable zoom in the structured light projector increases the focusable range of structured light. In addition, a small optical sensor utilizing the above structured light projector can be obtained. in the implementation of the present invention In the adjustable light projector of the example, an adjustable liquid crystal panel is used to switch the light beam between structured light and flood light. Therefore, the embodiment of the present invention integrates the flood light system and the structured light system into a single system, which reduces the need for Cost and volume of electronic devices with structured light and floodlight functions.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are given and described in detail with the accompanying drawings as follows.

10: Optical sensing device

102: Objects

100, 200a, 200b, 200c: Structured Light Projectors

104: Sensor

106: Opening

110: Light source

120, 220, 320, 420a, 420b, 520, 620, 720: Liquid crystal lens module

122: Liquid crystal lens unit

124: Solid State Lens

130: Diffractive Optical Elements

222: liquid crystal layer

224a: first substrate

224b: Second substrate

226: Liquid Crystal Molecule

228, 428a, 428b: Power

230a: First Electrode/Electrode

230b: Second Electrode/Electrode

230c: Third Electrode/Electrode

232a: alignment film/first alignment film

232b: alignment film/second alignment film

530a: Electrodes

530b: Floating Electrode

640: High impedance material layer

722: Liquid crystal cell

724: Anisotropic Lens

800, 800c, 800k: Adjustable Light Projector

810: Light source

811: Beam

820: Fixed Optical Phase Modulator

830: Drive

900, 900a, 900b, 900c, 900d, 900e, 900f, 900g, 900h, 900i, 900j: Adjustable LCD Panel

910: First substrate

920: Second substrate

930, 930a, 930b: liquid crystal layer

932, 932b: Liquid crystal molecules

934: Polymer Networks

934b: Polymer

940, 940g: the first electrode layer

942: Micro opening

942g, 952g: Conductive micropattern

950, 950g, 950h, 950j: the second electrode layer

960, 960a, 960d: the first alignment layer

970, 970a, 970d: the second alignment layer

980: High impedance layer

990: Insulation layer

A1: Optical axis

D: maximum diameter

F1, F2: focal length

L1: Alignment

LB: Beam

LP: polarized light

R1: Local same alignment region

R2: spot area

SL: Structured Light

△V: Voltage difference

FIG. 1 is a schematic diagram of an optical sensing device according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of the structured light projector of FIG. 1 .

3A to 3C are schematic cross-sectional views of another structured light projector according to at least one embodiment of the present invention.

4A and 4B are schematic cross-sectional views of different liquid crystal lens modules of FIG. 2 in two different states according to at least one embodiment of the present invention.

5 to 8 are schematic cross-sectional views of different liquid crystal lens modules of FIG. 2 according to at least one embodiment of the present invention.

9 is a schematic top view of a liquid crystal layer according to at least one embodiment of the present invention.

10A to 10B are schematic cross-sectional views of another liquid crystal lens module in two different states according to at least one embodiment of the present invention.

11A and FIG. 11B are schematic cross-sectional views of an adjustable light projector in a structured light mode and a flood light mode, respectively, according to an embodiment of the present invention.

12A , 12B and 12C are schematic top views of the first electrode layer in FIGS. 11A and 11B according to three embodiments of the present invention, respectively.

13A , 13B and 13C are schematic top views of other three variations of the first electrode layer of FIG. 12A .

14A is a schematic cross-sectional view of the adjustable liquid crystal panel of FIG. 11A .

14B and 14C illustrate other two variations of the adjustable liquid crystal panel of FIG. 14A.

15A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

15B is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

15C is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

FIG. 16A illustrates the alignment of the first alignment layer or the second alignment layer in FIG. 15A or FIG. 15C according to an embodiment of the present invention.

FIG. 16B illustrates another variation of the alignment of the first alignment layer or the second alignment layer in FIG. 15A or FIG. 15C according to another embodiment of the present invention.

FIG. 17A is a schematic cross-sectional view of a tunable light projector using the alignment layer of FIG. 16B .

FIG. 17B is a schematic top view of the light spot area and the alignment layer in FIG. 17A .

18A , 18B and 18C are schematic cross-sectional views of an adjustable liquid crystal panel and voltage differences applied to the liquid crystal layer in three different modes.

19A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

FIG. 19B is a schematic top view of the first substrate in FIG. 19A .

20A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

FIG. 20B is a schematic top view of the first substrate in FIG. 20A .

21A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

21B is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention.

22 is a schematic cross-sectional view of an adjustable light projector according to another embodiment of the present invention.

Exemplary embodiments will be described in detail below in conjunction with the drawings, and where possible, the same reference numerals and statements will be used in relation to the same elements or equivalent elements in the drawings.

In addition, for ease of description, expressions such as "underlying", "below", "lower", "overlying", "upper", "top" may be used herein. (top)," "bottom," "left," "right," and the like are spatially relative terms used to describe one element or feature and another element as illustrated in the figures or characteristic relationship. In addition to the orientation depicted in the figures, spatially relative terms are also intended to encompass the device in use or operation different orientations in . The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

FIG. 1 is a schematic diagram of an optical sensing device 10 according to an embodiment of the present invention. The optical sensing device 10 shown in FIG. 1 is a sensing device that uses structured light to detect objects. Specifically, the optical sensing device 10 includes a structured light projector 100 and a sensor 104 adjacent to the structured light projector 100 . The structured light projector 100 is used for generating structured light SL to the object 102 , and the sensor 104 is used for sensing the structured light SL reflected from the object 102 . Structured light SL may include, but is not limited to, multiple beams of light that project a light pattern onto object 102, such as a series of lines, circles, dots, or the like. Wherein the lines, circles, dots or the like can be arranged in order or out of order. Object 102 may be, for example, a palm, a human face, or any object having three-dimensional features. When the structured light SL is projected on the object 102 , the light pattern of the structured light SL is deformed by the uneven surface of the object 102 . The deformed structured light SL is then reflected from the object 102 and the reflected light passes through the opening 106 to the sensor 104 . For example, openings 106 may include lenses, apertures, transparent covers, and the like. The sensor 104 senses the deformation of the light pattern on the object 102 to calculate the depth of the surface of the object 102 , that is, the distance from a point on the surface of the object 102 to the sensor 104 . The sensor 104 may be connected to a processor (not shown) for calculating three-dimensional features of the object 102 .

FIG. 2 is a schematic cross-sectional view of a structured light projector 100 according to an embodiment of the present invention. The structured light projector 100 includes a light source 110 , a liquid crystal lens module 120 and a diffractive optical element (DOE) 130 . The light source 110 disposed at one end of the structured light projector 100 is used to emit the light beam LB. The light source 110 can be Light emitting diodes (LEDs), laser diodes, edge emitting lasers, vertical-cavity surface-emitting lasers (VCSELs), or any other or invisible (eg infrared (IR) or ultraviolet (UV)) beam LB. In some embodiments, the light source 110 may be a single IR laser diode, and in other embodiments, the light source 110 may be an IR laser diode array, and the number of light sources forming the light source 110 is not limited thereto.

The structured light projector 100 further includes a liquid crystal lens module 120 disposed on the path of the light beam LB. The liquid crystal lens module 120 can control the focus state of the light beam LB to provide at least two focus states for the structured light projector 100 . Optionally, a polarizer (not shown in the figure) is placed on the light beam LB in front of the liquid crystal lens module 120 to provide the liquid crystal lens module 120 with a polarized light beam LB.

As shown in FIG. 2 , the diffractive optical element 130 is disposed on the path of the light beam LB and behind the liquid crystal lens module 120 . However, the arrangement order of the diffractive optical element 130 and the liquid crystal lens module 120 is not limited to this. In some embodiments, the diffractive optical element 130 may be disposed on the path of the light beam LB and before the liquid crystal lens module 120 . In some embodiments, it may even be placed on the path of the light beam LB and between multiple elements of the liquid crystal lens module 120 . The diffractive optical element 130 is an optical element for generating a diffraction pattern for generating the structured light SL as described above with reference to FIG. 1 . For example, the diffractive optical element 130 may include a pattern that splits the light beam LB into a plurality of points, or a pattern that shapes the light beam LB to grid lines, but is not limited thereto. For simplicity, the light beam LB passing through the diffractive optical element 130 is hereinafter referred to as structured light SL. Furthermore, for ease of description, the x-direction and the z-direction that are perpendicular to each other are provided. For example, In this embodiment, the z-direction is defined as the direction perpendicular to the surface on which the light source 110 emits light.

3A-3C illustrate schematic cross-sectional views of various structured light projectors 200a-200c according to some embodiments of the present invention. The structured light projectors 200a to 200c are similar to the structured light projector 100 shown in FIG. 2 . The difference between the structured light projectors 200 a to 200 c and the structured light projector 100 is that the structured light projectors 200 a to 200 c include the liquid crystal lens unit 122 and the solid-state lens 124 but do not include the liquid crystal lens module 120 . In some embodiments, the combination of the liquid crystal lens unit 122 and the solid-state lens 124 can be used as the liquid crystal lens module 120 of FIG. 2 .

Referring to FIG. 3A , the solid-state lens 124 is disposed on the path of the light beam LB and is located between the diffractive optical element 130 and the light source 110 , and the liquid crystal lens unit 122 is disposed on the path of the light beam LB and located between the solid-state lens 124 and the diffractive optical element 130 between. In FIG. 3B , the solid-state lens 124 is disposed on the path of the light beam LB between the diffractive optical element 130 and the light source 110 , and the liquid crystal lens unit 122 is disposed on the side of the diffractive optical element 130 away from the light source 110 . In other words, the liquid crystal lens unit 122 is disposed on the path of the structured light SL. In FIG. 3C , the solid-state lens 124 is disposed on the path of the light beam LB and between the diffractive optical element 130 and the light source 110 , and the liquid crystal lens unit 122 is disposed on the path of the light beam LB and between the solid-state lens 124 and the light source 110 .

In some embodiments, the solid-state lens 124 may be a single lens or a combination with multiple lenses that defines the primary focal length of the structured light projector 200a. In some embodiments, the solid state lens 124 collimates the light beam LB before it enters the liquid crystal lens unit 122 or the diffractive optical element 130 . In some embodiments, the liquid crystal lens unit 122 has an adjustable zoom and includes at least one liquid crystal cell layer. The focal length of the liquid crystal lens unit 122 can be controlled by applying a voltage to control the orientation of liquid crystal molecules (not shown) within the liquid crystal lens unit 122 .

FIGS. 4A to 8 disclose some embodiments of a liquid crystal lens module that can be used as the liquid crystal lens module 120 of FIG. 2 . In some embodiments, the liquid crystal lens module disclosed in FIGS. 4A to 8 can be used as the liquid crystal lens unit 122 of FIGS. 3A to 3C , and the present invention is not limited thereto.

4A and 4B are schematic cross-sectional views of a liquid crystal lens module 220 according to an embodiment of the present invention. The liquid crystal lens module 220 includes a first substrate 224 a , a second substrate 224 b and a liquid crystal layer 222 . The liquid crystal layer 222 is sandwiched between the first substrate 224a and the second substrate 224b in the vertical direction (z-direction). The effective refractive index of each part of the liquid crystal layer 222 is related to the voltage applied to the first electrode 230a and the second electrode 230b, wherein the first electrode 230a is disposed on the first substrate 224a and interposed between the liquid crystal layer 222 and the first substrate 224a. During this time, the second electrode 230b is disposed on the second substrate 224b between the liquid crystal layer 222 and the second substrate 224b, and the voltage is provided by the power supply 228. The liquid crystal lens module 220 further includes alignment films 232 respectively disposed on the first electrode 230 a and the second electrode 230 b and in contact with opposite sides of the liquid crystal layer 222 . The alignment film 232a and the alignment film 232b have surface textures for providing initial orientation of the liquid crystal molecules 226 by controlling the pretilt angle and the polar angle of the liquid crystal molecules 226 . The pretilt angle refers to the angle between the long axis of the liquid crystal molecules 226 and the plane perpendicular to the z-direction; the polar angle refers to the angle between the long axis of the liquid crystal molecules 226 on the plane perpendicular to the z-direction and a fixed axis. (eg: along the x-direction). Used for the alignment film 232 of this embodiment The material may be a polymer (eg, polyimide), but is not limited thereto.

Referring to FIG. 4A , the liquid crystal layer 222 of the liquid crystal lens module 220 has a non-uniform thickness. As shown in FIG. 4A , the liquid crystal layer 222 has a curved surface and a flat surface, and is thickest at the middle portion. The curved surface of the liquid crystal layer 222 corresponds to the curved surface of the first substrate 224a, the curved first electrode 230a and the curved upper alignment film 232a. In addition, in this embodiment, when the electrodes 230a and 230b are disconnected from the power source 228, all the liquid crystal molecules 226 in the liquid crystal layer 222 are arranged in substantially the same orientation. That is, the long axes of all liquid crystal molecules 226 are along the horizontal x-direction, where the x-direction is orthogonal to the z-direction. When the electrodes 230a and 230b are turned on with the power source 228, as shown in FIG. 4B, the orientation of the liquid crystal molecules 226 is rotated so that the long axis and the z-direction are aligned.

In this embodiment, the liquid crystal lens module 220 of FIGS. 4A to 4B can be used as a refractive lens. Specifically, when the liquid crystal lens module 220 is not connected to the power source 228, the liquid crystal layer 222 has a first effective refractive index such that when combined with the convex shape of the liquid crystal lens module 220, light entering along the z-direction will be focused to The first focal length F1. In FIG. 4B , when the liquid crystal lens module 220 is connected to the power supply 228 , the alignment of the liquid crystal molecules 226 along the z-axis will change the effective refractive index of the liquid crystal layer 222 to the second effective refractive index, so that when the liquid crystal layer 222 is aligned with the convexity of the liquid crystal layer 222 When combined, light entering in the z-direction is focused to the second focal length F2. Therefore, the focal length of the liquid crystal lens module 220 can be controlled by turning on or off the power supply 228 .

FIG. 5 is a schematic cross-sectional view of a liquid crystal lens module 320 according to an embodiment of the present invention. The liquid crystal lens module 320 includes a first substrate 224a, a second substrate 224b, a liquid crystal layer 222, a first electrode 230a, a second electrode 230b, an alignment film 232a and 232b, the arrangement is similar to that of the liquid crystal lens module 220. 5 , the difference between the liquid crystal lens module 320 and the liquid crystal lens module 220 lies in the shapes of the first substrate 224a, the first electrode 230a, the second electrode 230b and the first alignment film 232a. Specifically, in FIG. 5, the first substrate 224a is a substrate with a uniform thickness in the z-direction, the first electrode 230a and the first alignment film 232a are flat, and the second electrode 230b and the second alignment film are flat 232b is stepped. Since the second electrode 230b and the second alignment film 232b are stepped, the liquid crystal layer 222 has a liquid crystal layer with a non-uniform thickness and has optical properties of a diffractive lens. For example, the stepped shapes of the second electrode 230b and the second alignment film 232b can be designed so that the liquid crystal layer 222 following the stepped shapes can be a Fresnel lens, but the invention is not limited thereto. Similar to the liquid crystal lens module 220, the focal length of the liquid crystal lens module 320 can be controlled by applying a voltage between the first electrode 230a and the second electrode 230b.

6A is a schematic cross-sectional view of a liquid crystal lens module 420a according to an embodiment of the present invention.

In FIG. 6A , the liquid crystal lens module 420 a includes a first substrate 224 a , a second substrate 224 b , a liquid crystal layer 222 , a second electrode 230 b , and alignment films 232 a and 232 b , which are arranged similarly to the liquid crystal lens module 220 . 6A , the difference between the liquid crystal lens module 420a and the liquid crystal lens module 220 lies in the first substrate 224a, the first electrode 230a and the first alignment film 232a. Specifically, in FIG. 6A, the first substrate 224a is a substrate having a uniform thickness in the z-direction, the first electrode 230a is a patterned electrode with a gap or opening therebetween and is disposed on the first substrate 224a and the liquid crystal On the opposite side of the layer 222, and the first alignment film 232a is flat. Therefore, this embodiment The liquid crystal layer 222 has a uniform thickness. In some embodiments, the first electrode 230a may also be disposed between the first substrate 224a and the first alignment film 232a, but is not limited thereto.

Based on the pattern of the first electrode 230a, the voltage in the liquid crystal layer 222 is unevenly distributed, causing the liquid crystal molecules 226 to have different orientations when the first electrode 230a is connected to a power source. In some embodiments, the pattern of the first electrode 230a may be any other pattern than the pattern shown in FIG. 6A. The non-uniform distribution of liquid crystal orientation produces a distributed index of refraction. The liquid crystal lens module 420a may be a refractive lens or a diffractive lens depending on the distribution of the refractive index.

6B is a schematic cross-sectional view of the liquid crystal lens module 420b according to an embodiment of the present invention. The liquid crystal lens module 420b is similar to the liquid crystal lens module 420a, except that the liquid crystal lens module 420b further includes a third electrode 230c. The third electrode 230c is adjacent to the first electrode 230a and away from the liquid crystal layer 222 . In this embodiment, the first electrode 230a and the second electrode 230b may be connected to the first power source 428a to provide the voltage V1, and the third electrode 230c and the second electrode 230b may be connected to the second power source 428b to provide the voltage V2. The addition of the third electrode 230c allows further control of the voltage distribution in the liquid crystal layer 222 to provide further fine-tuning of the optical properties. The liquid crystal lens module 420b may be a refractive lens or a diffractive lens depending on the distribution of the refractive index.

7 is a schematic cross-sectional view of a liquid crystal lens module 520 according to an embodiment of the present invention. The liquid crystal lens module 520 is a liquid crystal lens module having a liquid crystal layer 222 of uniform thickness. Specifically, the liquid crystal lens module 520 includes a first substrate 224a and a second substrate 224b, a liquid crystal layer 222, a second electrode 230b, and alignment films 232a and 232b, Its arrangement is similar to the liquid crystal lens module 420a. The difference between the liquid crystal lens module 520 and the liquid crystal lens module 420a lies in the position of the first electrode 230a and the structure of the second electrode 230b. Specifically, in FIG. 7, the first electrode 230a is disposed between the first substrate 224a and the first alignment film 232a, and the second electrode 230b is a pixelated electrode. The second electrode 230b includes at least one electrode 530a connected to the power source 228 and at least one floating electrode 530b disposed adjacent to the electrode 530a to form a pixelated structure. The floating electrodes 530b are separated by an insulator disposed therebetween, eg, by a portion of the first alignment film 232b, as shown in FIG. 7 . In some embodiments, the floating electrode 530b may also be disposed on the first substrate 224a, the second substrate 224b, or both the first substrate 230a and the second substrate 230b. The voltage on the floating electrode 530b of the second electrode 230b is related to the adjacent electrode 530a. The floating electrode 530b provides more voltage variation pitch to better control the orientation of the liquid crystal molecules in the liquid crystal layer 222 . Alternatively, some or all of the floating electrodes 530b may also be individually connected to other power sources to further control the liquid crystal molecules. Depending on the distribution of the refractive index, the liquid crystal lens module 520 may be a refractive lens or a diffractive lens.

8 is a schematic cross-sectional view of a liquid crystal lens module 620 according to an embodiment of the present invention. The liquid crystal lens module 620 is similar to the liquid crystal lens module 520, except that the liquid crystal lens module 620 has a pixelated first electrode 230a, and further includes a pixelated first electrode 230a and the first alignment film 232a. High resistance material layer 640 . The high resistance material layer 640 provides a continuously varying voltage between the electrodes, thus improving the quality of the image formed. The sheet resistance of the high resistance material layer 640 ranges from 10 ⁹ to 10 ¹⁴ ohms per square (Ω/sq). For example, the high-resistance material layer 640 is made of semiconductor materials (including III-V semiconductor compounds or II-VI semiconductor compounds) or polymer materials (including poly(3,4-ethylenedioxythiophene); PEDOT))) made. Of course, the high-resistance material layer 640 can be implemented in any of the above-mentioned liquid crystal lens modules, and can have any other patterns. The present invention is not limited to this.

9 is a schematic top view (ie, along the z-direction) of the liquid crystal layer 222 according to an embodiment of the present invention. Specifically, FIG. 9 is an exemplary arrangement pattern of liquid crystal molecules in the liquid crystal layer 222 on the x-y plane due to the control of the alignment film. The y-direction provided in Figure 9 is perpendicular to the x and z directions. As shown in FIG. 9, the polar angles of the liquid crystal molecules are controlled by the alignment film to form a Pancharatnam-Berry phase liquid crystal lens. Other liquid crystal lenses may be formed by alignment films having different surface patterns, and the present invention is not limited thereto.

10A and 10B are schematic cross-sectional views of a liquid crystal lens module 720 according to an embodiment of the present invention. In FIGS. 10A and 10B , the liquid crystal lens module 720 includes a liquid crystal cell 722 and an anisotropic lens 724 , wherein the liquid crystal cell 722 is connected to the power source 228 . In the liquid crystal lens module 720, the liquid crystal cells 722 are disposed on the path of light polarized perpendicular to the x and z directions (polarized light LP as shown in FIG. 10A). The liquid crystal cell 722 is configured to control the polarization of incident light.

10A and 10B, when the liquid crystal cell 722 is in the off state (no voltage is applied), the polarization of the incident light is not affected, and when the liquid crystal cell 722 is in the on state (voltage is applied), the polarization of the incident light is rotated by 90 degrees to x direction. In other words, when the liquid crystal cell 722 is turned on, the liquid crystal cell acts as a half-wave plate to change the incidence Polarization of light. An anisotropic lens 724 is provided on the optical path passing through the liquid crystal cell 722 . The refractive index (that is, the focal length) of the anisotropic lens 724 depends on the polarization of the light. For example, when the light is polarized in the direction of the optical axis A1 of the anisotropic lens, the refractive index is the largest, and when the polarization direction of the light is positive to the optical axis A1. When intersecting, the refractive index is the smallest. Because the opening and closing of the liquid crystal cell 722 changes the polarization of the light, the focal length of the anisotropic lens also changes. The liquid crystal lens module 720 is also referred to as a passive liquid crystal lens because the liquid crystal cells do not actively focus or scatter light.

The voltage distribution applied to the liquid crystal lens module, the liquid crystal lens unit, and the electrodes of the liquid crystal cell as described above may be controlled by a controller coupled to the electrodes. In some embodiments, the controller is, for example, a central processing unit (CPU), a microprocessor, a digital signal processor (DSP), a programmable controller, a programmable logic device (PLD) ) or other similar elements, or combinations of said elements, are not particularly limited by the present invention. Furthermore, in some embodiments, each function of the controller may be implemented in multiple code codes. The code will be stored in memory or non-transitory storage medium so that the code can be executed by the controller. Alternatively, in one embodiment, each function of the controller may be implemented in one or more circuits. The present invention is not intended to limit whether each function of the controller is implemented by software or hardware.

By providing a liquid crystal lens with adjustable zoom in the structured light projector, the focusing range of the structured light projector becomes adjustable and can cover a wider range, enabling the measurement of features at different distances on a 3D object. In addition, compared with the traditional voice coil motor (VCM) in the focusing lens, the use of liquid crystal Lensed optical projectors have the advantage of being smaller and lower power consumption. Therefore, the optical projector of the present invention can be easily installed in a mobile electronic device to provide 3D sensing features for the mobile electronic device.

11A and FIG. 11B are schematic cross-sectional views of an adjustable light projector in a structured light mode and a flood light mode, respectively, according to an embodiment of the present invention. Referring to FIGS. 11A and 11B , the adjustable light projector 800 of this embodiment includes at least one light source 810 (a plurality of light sources 810 are taken as an example in FIGS. 11A and 11B ), a fixed optical phase modulator 820 , a Adjustable liquid crystal panel 900 and a driver 830 . These light sources 810 are used for emitting a plurality of light beams 811 (in FIG. 11A and FIG. 11B , one light source 810 is schematically shown as an example for emitting one light beam 811 ). In this embodiment, the light sources 810 are respectively a plurality of light-emitting regions (or light-emitting points) of a vertical resonant cavity surface-emitting laser, or are respectively a plurality of edge-emitting lasers (EEL), or a plurality of other suitable laser emitters or laser diodes, respectively.

The fixed optical phase modulator 820 is disposed on the path of the light beam 811 and is used to modulate the phase of the light beam 811 . In this embodiment, the fixed optical phase modulator 820 is, for example, a diffractive optical element or a lens array, which modulates the light beam 811 into a structured light.

The adjustable liquid crystal panel 900 is disposed on the path of the light beam 811 and is used to switch the light beam 811 between a structured light (as shown in FIG. 11A ) and a flood light (as shown in FIG. 11B ). In this embodiment, the adjustable liquid crystal panel 900 is disposed on the path of the light beam 811 from the fixed optical phase modulator 820 . The adjustable liquid crystal panel 900 includes a first substrate 910, a second substrate 920, a liquid crystal layer 930, A first electrode layer 940 and a second electrode layer 950 . The liquid crystal layer 930 is disposed between the first substrate 210 and the second substrate 920 . At least one of the first electrode layer 940 and the second electrode layer 950 is a patterned layer. 11A and 11B illustrate that the first electrode layer 940 is a patterned layer. However, in other embodiments, the second electrode layer 950 may be a patterned layer, or both the first electrode layer 940 and the second electrode layer 950 are patterned layers. In this embodiment, the first substrate 910 and the second substrate 920 are transparent substrates, such as glass substrates or plastic substrates. The first electrode layer 940 and the second electrode layer 950 may be made of indium tin oxide (ITO), other conductive metal oxides or other transparent conductive materials.

The first electrode layer 940 and the second electrode layer 950 are both disposed on one of the first substrate 910 and the second substrate 920 , or disposed on the first substrate 910 and the second substrate 920 respectively. The driver 830 is electrically connected to the first electrode layer 940 and the second electrode layer 950, and is used to change the voltage difference between the first electrode layer 940 and the second electrode layer 950, so that the light beam 811 is between the structured light and the flood light. switch between. Specifically, the optical spatial phase distribution of the liquid crystal layer 930 changes with the change of the voltage difference, so that the light beam 811 is switched between structured light and flood light.

For example, in FIG. 11A , the voltage difference between the first electrode layer 940 and the second electrode layer 950 is about zero, and the refractive index distribution of the liquid crystal layer 930 is uniform, so the liquid crystal layer 930 resembles a transparent layer. Therefore, the structured light from the fixed optical phase modulator 820 will pass through the transparent layer and still be a structured light, and the tunable light projector 800 is in a structured light mode. In FIG. 11B , the voltage difference between the first electrode layer 940 and the second electrode layer 950 is not equal to zero, and the refraction of the liquid crystal layer 930 The rate distribution is non-uniform, so the liquid crystal layer 930 resembles a lens array. Therefore, the structured light from the fixed optical phase modulator 820 is converted into a flood light by the lens array, and the tunable light projector 800 is in a flood light mode. This structured light can be irradiated on the object to form a light pattern with multiple dots, with stripes, or with other suitable patterns on the object. This floodlight illuminates objects evenly.

In the adjustable light projector of this embodiment, the adjustable liquid crystal panel 900 is used to switch the light beam 811 between structured light and flood light, so this embodiment integrates the flood light system and the structured light system into a single system, It reduces the cost and volume of electronic devices with structured light and floodlight functions.

In another embodiment, the fixed optical phase modulator 820 is used to modulate the light beam 811 into a flood light. In addition, when the voltage difference between the first electrode layer 940 and the second electrode layer 950 is about zero, the flood light from the fixed optical phase modulator 820 penetrates the liquid crystal layer 930 (which is a transparent layer at this time) and Still a floodlight. When the voltage difference between the first electrode layer 940 and the second electrode layer 950 is not zero, the flood light from the fixed optical phase modulator 820 is blocked by the liquid crystal layer 930 (at this time it is an optical layer similar to a lens array) into a structured light.

In yet another embodiment, the fixed optical phase modulator 820 is used to modulate the light beam into a collimated light, and the two voltage differences between the first electrode layer 940 and the second electrode layer 950 respectively adjust the liquid crystal layer 930 Switching to two refractive index profiles, and then switching the collimated light from the fixed optical phase modulator 820 into a structured light and a flood light, respectively.

12A, FIG. 12B and FIG. 12C are the first images in FIG. 11A and FIG. 11B, respectively. Schematic top view of an electrode layer according to three embodiments of the present invention. 12A , 12B and 12C, the patterned layer (such as the first electrode layer 940 or the second electrode layer 950, and the first electrode layer 940 is shown as an example) has a plurality of micro-openings 942, It has a maximum diameter D of less than 1 mm. The shapes of the micro openings 942 include circle (as shown in FIG. 12A ), rectangle (as shown in FIG. 12B ), square, hexagon (as shown in FIG. 12C ), other geometric shapes, and other irregular shapes or a combination thereof.

13A , 13B and 13C are schematic top views of other three variations of the first electrode layer of FIG. 12A . Referring to FIGS. 12A , 13A, 13B and 13C, the sizes and positions of the micro-opening holes 942 may be regular or irregular. For example, in FIG. 12A , the sizes of the micro-opening holes 942 are equal to each other, and the positions of the micro-opening holes 942 are regular. In FIG. 13A, the sizes of the micro-opening holes 942 are equal to each other, and the positions of the micro-opening holes 942 are irregular. In FIG. 13B , the micro-apertures 942 have different sizes, and the positions of the micro-apertures 942 are regular. In FIG. 13C, the micro-apertures 942 have different sizes, and the positions of the micro-apertures 942 are irregular.

14A is a schematic cross-sectional view of the adjustable liquid crystal panel of FIG. 11A , and FIGS. 14B and 14C illustrate other two variations of the adjustable liquid crystal panel of FIG. 14A . Referring to FIG. 14A , the adjustable liquid crystal panel 900 has a liquid crystal layer 930 including a polymer network liquid crystal (PNLC) including liquid crystal molecules 932 and a polymer network 934 . Referring to FIG. 14B, the adjustable liquid crystal panel 900a may have a liquid crystal layer 930a including a nematic liquid crystal. Referring to FIG. 14C, the adjustable liquid crystal panel 900b may have a liquid crystal layer 930b including polymer dispersed liquid crystal (polymer dispersed liquid crystal) liquid crystal, PDLC), which includes liquid crystal molecules 932b and polymers 934b.

15A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention. Referring to FIG. 15A, the adjustable liquid crystal panel 900c of this embodiment is similar to the adjustable liquid crystal panel 900a of FIG. 14B, and the main differences are as follows. In this embodiment, the adjustable liquid crystal panel 900c further includes a first alignment layer 960 and a second alignment layer 970 . The first alignment layer 960 is disposed between the first substrate 910 and the liquid crystal layer 930a, and the second alignment layer 970 is disposed between the second substrate 920 and the liquid crystal layer 930a. In this embodiment, the first alignment layer 960 is disposed between the first electrode layer 940 and the liquid crystal layer 930a, and the second alignment layer 970 is disposed between the second electrode layer 950 and the liquid crystal layer 930a. In this embodiment, the first alignment layer 960 and the second alignment layer 970 are parallel alignment layers.

15B is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention. Referring to FIG. 15B , the adjustable liquid crystal panel 900d of this embodiment is similar to the adjustable liquid crystal panel 900c, and the main differences are as follows. In the adjustable liquid crystal panel 900d of this embodiment, the first alignment layer 960d and the second alignment layer 970d are vertical alignment layers.

15C is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention. Referring to FIG. 15C , the adjustable liquid crystal panel 900e of this embodiment is similar to the adjustable liquid crystal panel 900c, and the main differences are as follows. In the adjustable liquid crystal panel 900e of this embodiment, the first alignment layer 960 and the second alignment layer 970d are a combination of a vertical alignment layer and a horizontal alignment layer. For example, the first alignment layer 960 is a horizontal alignment layer, and the second alignment layer 970d is a vertical alignment layer.

FIG. 16A illustrates the alignment direction of the first alignment layer or the second alignment layer in FIG. 15A or FIG. 15C according to an embodiment of the present invention. Referring to FIG. 16A , in one embodiment, the alignment L1 of the first alignment layer 960 and the second alignment layer 970 has a uniform spatial distribution. In other words, the azimuthal angles of the alignments in different regions of the first alignment layer 960 or the second alignment layer 970 are the same as each other.

FIG. 16B illustrates another variation of the alignment of the first alignment layer or the second alignment layer in FIG. 15A or FIG. 15C according to another embodiment of the present invention. Referring to FIG. 16B, in another embodiment, the alignment L1 of the first alignment layer 960a and the second alignment layer 970a have irregular spatial distribution. In other words, the azimuth angles of the alignments in different regions of the first alignment layer 960a or the second alignment layer 970a are different from each other. Different alignments and different azimuth angles can refract or diffract light beams 811 of different polarization directions from the light source 810 .

FIG. 17A is a schematic cross-sectional view of a tunable light projector using the alignment layer of FIG. 16B . FIG. 17B is a schematic top view of the light spot area and the alignment layer in FIG. 17A . Referring to FIGS. 17A and 17B , the adjustable light projector 800 c of this embodiment is similar to the adjustable light projector 800 of FIG. 11A , and the main differences are as follows. In the adjustable light projector 800c of the present embodiment, the locally identical alignment region R1 of the irregular spatial distribution of the alignment of the first alignment layer 960a and the second alignment layer 970a is smaller than that on the adjustable liquid crystal panel 900c from the fixed A light spot area R2 irradiated by the light beam 811 of the optical phase modulator 820 . Therefore, the light beams 811 with various polarization directions can be refracted or diffracted by the liquid crystal layer 900c.

18A , 18B and 18C are schematic cross-sectional views of an adjustable liquid crystal panel and voltage differences applied to the liquid crystal layer in three different modes. 18A , 18B and 18C, the adjustable liquid crystal panel 900f of this embodiment is similar to the adjustable liquid crystal panel 900b of FIG. 14C, and the main differences are as follows. The adjustable liquid crystal panel 900f of this embodiment further includes a high impedance layer 980 (same as the high impedance material layer 640 in FIG. 8 ), which is adjacent to the patterned layer (eg, the first electrode layer 940 ). In FIG. 18A, when the voltage difference between the first electrode layer 940 and the second electrode layer 950 is zero, the voltage difference ΔV applied to the liquid crystal layer 930b is zero, and the liquid crystal layer 930b is in a scattering mode, and is used for The beam 811 from the fixed optical phase modulator 820 is scattered.

In 18B, when the voltage difference between the first electrode layer 940 and the second electrode layer 950 is a high-frequency alternating voltage (the “high frequency” is, for example, a frequency greater than 1 kHz and less than or equal to 60 kHz), applied to the liquid crystal layer The voltage difference ΔV of 930 gradually changes with the position due to the action of the high impedance layer 980, and the liquid crystal layer 930b is in a scattering and condensing mode for slightly scattering and condensing the light beam 811 from the fixed optical phase modulator 820 .

In 18C, when the voltage difference between the first electrode layer 940 and the second electrode layer 950 is a low-frequency AC voltage (the "low frequency" is, for example, a frequency greater than or equal to 60 Hz and less than or equal to 1 kHz), applied to the liquid crystal layer 930 The voltage difference ΔV of ΔV remains approximately constant at different positions, the liquid crystal layer 930b is in a transparent mode and resembles a transparent layer, and the light beam 811 penetrates the liquid crystal layer 930b. In addition, the above-mentioned "high frequency" is larger than the above-mentioned "low frequency".

19A is a cross-section of an adjustable liquid crystal panel according to another embodiment of the present invention FIG. 19B is a schematic top view of the first substrate in FIG. 19A . Referring to FIGS. 19A and 19B , the adjustable liquid crystal panel 900g of this embodiment is similar to the adjustable liquid crystal panel 900c of FIG. 15A , and the main differences are as follows. In the adjustable liquid crystal panel 900g of the present embodiment, both the first electrode layer 940g and the second electrode layer 950g are disposed on the same substrate (eg, the first substrate 910 ), and both are patterned layers. The first electrode layer 940g and the second electrode layer 950g have an in-plane switch (IPS) electrode design. Specifically, the first electrode layer 940g includes a plurality of conductive micropatterns 942g, and the second electrode layer 950g includes a plurality of conductive micropatterns 952g. The conductive micropatterns 942g and the conductive micropatterns 952g are alternately arranged along one direction (eg, the right direction in FIGS. 19A and 19B ). The conductive micropattern 942g and the conductive micropattern 952g may have a linear shape. For example, each of conductive micropattern 942g and conductive micropattern 952g may extend in a direction perpendicular to the plane of FIG. 19A. However, in this embodiment, the conductive micropattern 942g and the conductive micropattern 952g may have a zigzag shape as shown in FIG. 19B .

20A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention, and FIG. 20B is a schematic top view of the first substrate in FIG. 20A . The adjustable liquid crystal panel 900h of this embodiment is similar to the adjustable liquid crystal panel 900g in FIG. 19A, and the main differences are as follows. In the adjustable liquid crystal panel 900h of this embodiment, the first electrode layer 940g and the second electrode layer 950h have a fringe-field switch (FFS) electrode design. The second electrode layer 950h is a flat continuous layer, which is interposed between the first electrode layer 940g and the first substrate 910, and the insulating layer 990 between the first electrode layer 940g and the second electrode layer 950 is arranged to insulate each other. edge. The first electrode layer 940g in FIGS. 20A and 20B is the same as the description of the first electrode layer 940g in FIGS. 19A and 19B .

21A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention. Referring to FIG. 21A, the adjustable liquid crystal panel 900j of this embodiment is similar to the adjustable liquid crystal panel 900a of FIG. 14B, and the main differences are as follows. In the adjustable liquid crystal panel 900j, the first electrode layer 940 and the second electrode layer 950j are two patterned layers respectively disposed on the first substrate 910 and the second substrate 920, and the patterns of the two patterned layers are identical to each other. However, in other embodiments, the patterns of the two patterned layers may be different from each other.

21B is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention. Referring to FIG. 21B , the adjustable liquid crystal panel 900i of this embodiment is similar to the adjustable liquid crystal panel 900g or 900h in FIG. 19A or FIG. 20A , and the main differences are as follows. The adjustable liquid crystal panel 900i of the present embodiment includes a first electrode layer 940g and a second electrode layer 950g as shown in FIG. 19A disposed on the first substrate 910 , and includes a first electrode layer 940g and a second electrode layer 950g disposed on the second substrate 920 as shown in FIG. 19A . The first electrode layer 940g and the second electrode layer 950 shown in 20A. That is, the first substrate 910 side has an electrode design of lateral electric field switching, and the second substrate 920 side has an electrode design of fringe field switching. However, in other embodiments, both the first substrate 910 side and the second substrate 920 side may have lateral electric field switching electrode designs, or both the first substrate 210 side and the second substrate 920 side may have fringe field switching electrodes design.

22 is a schematic cross-sectional view of an adjustable light projector according to another embodiment of the present invention. The adjustable light projector 800k of the present embodiment is the adjustable light projector 800k of FIG. 11A and FIG. 11B The type light projector 800 is similar, and the difference between the two lies in the arrangement order of the fixed optical phase modulator 820 and the adjustable liquid crystal panel 900 . In FIGS. 11A and 11B , the fixed optical phase modulator 820 is disposed between the light source 810 and the adjustable liquid crystal panel 900 . However, in this embodiment, the adjustable liquid crystal panel 200 is disposed in the light source 810 and the fixed optical phase modulator 820, that is, the fixed optical phase modulator 820 is disposed on the path of the light beam from the adjustable liquid crystal panel 200, In this way, when the adjustable liquid crystal panel 900 is switched between different modes as in the previous embodiment, the light beam passing through the fixed optical phase modulator 820 can still be switched between structured light and flood light.

To sum up, in the adjustable light projector of the embodiment of the present invention, the adjustable liquid crystal panel is used to switch the light beam between the structured light and the flood light, so the embodiment of the present invention combines the flood light system with the structured light The system is integrated into a single system, which reduces the cost and volume of electronic devices with structured light and floodlight functions. Each of the above-mentioned various types of adjustable light projectors can replace any one of the above-mentioned various types of structured light projectors in the optical sensing device to form an optical sensing device having both the flood light recognition function and the structured light recognition function. In the flood light recognition function, the sensor can sense the object and determine whether the object is a human face. In the structured light recognition function, the sensor can sense the light pattern on the object, and determine whether the detected face is the face of a user of an electronic device.

Although the present invention has been disclosed above by the embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, Protection scope of the present invention The scope of the patent application attached shall prevail.

800: Adjustable Light Projector

810: Light source

811: Beam

820: Fixed Optical Phase Modulator

830: Drive

900: Adjustable LCD panel

910: First substrate

920: Second substrate

930: Liquid crystal layer

940: first electrode layer

950: second electrode layer

Claims (17)

An adjustable light projector, comprising: a light source for emitting a light beam; a fixed optical phase modulator, disposed on the path of the light beam, and used to modulate the phase of the light beam; an adjustable liquid crystal panel, configured On the path of the light beam, and used to switch the light beam between a structured light and a flood light, the adjustable liquid crystal panel includes: a first substrate; a second substrate; a liquid crystal layer, disposed on the first substrate between a substrate and the second substrate; a first electrode layer; and a second electrode layer, wherein at least one of the first electrode layer and the second electrode layer is a patterned layer, and the first electrode layer Both the electrode layer and the second electrode layer are arranged on one of the first substrate and the second substrate, or are arranged on the first substrate and the second substrate respectively; a first alignment layer is arranged on the between the first substrate and the liquid crystal layer; and a second alignment layer disposed between the second substrate and the liquid crystal layer, wherein at least part of different regions of the first alignment layer or the second alignment layer The azimuthal angles of the alignments are different from each other, and the different azimuthal angles of the alignments in the at least partially different regions are used to refract or diffract light beams of different polarization directions from the light source; and a driver electrically connected to the first electrode layer and the second electrode layer, wherein the driver is used to change the voltage difference between the first electrode layer and the second electrode layer, and to change the refractive index of the liquid crystal layer The distribution mode makes the light beam switch between the structured light and the flood light, wherein when the voltage difference between the first electrode layer and the second electrode layer is not equal to zero, the liquid crystal layer is equivalent to a lens array optical layer. The adjustable light projector of claim 1, wherein the fixed optical phase modulator is used to modulate the light beam into structured light or flood light. The adjustable light projector of claim 1, wherein the fixed optical phase modulator is used to modulate the light beam into a collimated light. The adjustable light projector as claimed in claim 1, wherein the patterned layer has a plurality of micro-opening holes with a maximum diameter of less than 1 mm. The adjustable light projector according to claim 4, wherein the shapes of the micro-openings include circles, rectangles, squares, hexagons, or combinations thereof. The adjustable light projector as claimed in claim 4, wherein the sizes and positions of the micro-opening holes are regular. The adjustable light projector as claimed in claim 4, wherein the sizes and positions of the micro-opening holes are irregular. The adjustable light projector as claimed in claim 1, wherein the optical spatial phase distribution of the liquid crystal layer changes with the change of the voltage difference, so that the light beam is switched between the structured light and the flood light . The adjustable light projector of claim 1, wherein the liquid crystal layer comprises nematic liquid crystal, polymer dispersed liquid crystal or polymer network liquid crystal. The adjustable light projector of claim 1, wherein the first alignment layer and the second alignment layer are vertical alignment layers, horizontal alignment layers, or a combination thereof. The adjustable light projector as claimed in claim 1, wherein the at least some of the different regions include partially identical alignment regions, and the partially identical alignment regions are smaller than the area on the adjustable liquid crystal panel that is modulated by the fixed optical phase from the fixed optical phase. A light spot area of the device illuminated by the beam. The adjustable light projector as described in claim 1, further comprising a high-impedance layer adjacent to the patterned layer. The adjustable light projector of claim 1, wherein the patterned layer comprises a plurality of conductive micropatterns. The adjustable light projector of claim 13, wherein the conductive micropatterns have a linear shape or a zigzag shape. The adjustable light projector of claim 1, wherein the first electrode layer and the second electrode layer have electrode designs of lateral electric field switching or fringe field switching. The adjustable light projector as claimed in claim 1, wherein the first electrode layer and the second electrode layer are two patterned layers, respectively disposed on the first substrate and the second substrate, and the two The patterns of the patterned layers are different from each other. The adjustable light projector as claimed in claim 1, wherein the first electrode layer and the second electrode layer are two patterned layers, respectively disposed on the first substrate and the second substrate, and the two The patterns of the patterned layers are the same as each other.

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