TWI747224B - Tunable light projector - Google Patents

Abstract

A tunable light projector including a light source, a fixed optical phase modulator, and a tunable liquid crystal panel is provided. The light source is configured to emit a light beam, and 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 be switched between a plurality of states, wherein the plurality of states include a lens array state in which the tunable liquid crystal panel comprises a lens array.

Description

Adjustable light projector

The 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. TOF technology uses pulsed laser and complementary metal oxide semiconductor (CMOS) sensors 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 infrared light source (IR source) is projected onto a diffractive optical element (DOE) to generate a two-dimensional diffraction pattern, and then a sensor is used to collect the reflected light. The three-dimensional distance of an object can be calculated using trigonometry. Structured light technology is limited to 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 structured light technology problems, some people have proposed a system in which an apodized lens is added to the lens group to generate multiple focal lengths. However, this approach sacrifices light efficiency and the number of points and resolution of the two-dimensional diffraction pattern.

In addition, in the three-dimensional face recognition of mobile devices, both the floodlight system and the structured light system are used to achieve the three-dimensional 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 human face is the user of the mobile device s face. However, the simultaneous use of two systems (ie flood light system and structured light system) in a mobile device will take up a lot of space and is more expensive.

The invention provides an optical sensing device that uses liquid crystal to control the focusing of structured light.

The invention provides a structured light projector that uses liquid crystal to control the focusing of the structured light.

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

An embodiment of the present invention provides an optical sensing device suitable for detecting objects or features of objects. The optical sensing device includes a structured light projector and a sensor. The structured light projector is used to project 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 to emit a light beam. The diffractive optical element is arranged on the path of the light beam and used to generate a diffractive pattern to form structured light. The liquid crystal lens module is configured 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. Reflected light is the reflection of structured light from an object.

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 to emit a light beam. The diffractive optical element is arranged on the path of the light beam and used to generate a diffractive pattern to form structured light. The liquid crystal lens module is configured 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 to emit a light beam. The fixed optical phase modulator is arranged on the path of the light beam and used to modulate the phase of the light beam. The adjustable liquid crystal panel is arranged 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, 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. The first electrode layer and the second electrode layer are both configured on one of the first substrate and the second substrate, or are respectively configured 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 to change 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.

An embodiment of the present invention provides an adjustable light projector, which includes a light source, a fixed optical phase modulator, and an adjustable liquid crystal panel. The light source is used to emit a light beam. The fixed optical phase modulator is arranged on the path of the light beam and used to modulate the phase of the light beam. The adjustable liquid crystal panel is arranged on the path of the light beam and used to switch between a plurality of states, wherein these states include a lens array state, and the adjustable liquid crystal panel in the lens array state includes a lens array.

Based on the above, the structured light projector of 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 the structured light. In addition, it is possible to obtain a small-sized optical sensor using the above-mentioned structured light projector. In the adjustable light projector of the embodiment of the present invention, the adjustable liquid crystal panel is used to switch the beam between structured light and floodlight. Therefore, the embodiment of the present invention integrates the floodlight system and the structured light system into a single system , Which reduces the 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 comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

The exemplary embodiments will be described in detail below in conjunction with the drawings. For the same elements or equivalent elements in the drawings, the same reference numerals and statements are used as much as possible.

In addition, for ease of description, examples such as "underlying", "below", "lower", "overlying", "upper", and "top" can be used in this article. (Top)”, “bottom”, “left”, “right” and similar spatially relative terms to describe one element or feature as shown in the figure and another element Or the relationship of characteristics. In addition to the orientations depicted in the figures, spatial relative terms are also intended to cover different orientations of the device in use or operation. The device can be oriented in other ways (rotated by 90 degrees or in other orientations), and the spatial relative descriptors used in this article can also be interpreted accordingly.

FIG. 1 is a schematic diagram of an optical sensing device 10 according to an embodiment of the 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 to generate structured light SL to the object 12, and the sensor 104 is used to sense the structured light SL reflected from the object 12. The structured light SL may include, but is not limited to, multiple light beams that project a light pattern onto the object 12, such as a series of lines, circles, dots, or the like. The lines, circles, dots or the like can be arranged in an orderly or disorderly arrangement. The object 12 may be, for example, a palm, a human face, or any object with three-dimensional features. When the structured light SL is projected to the object 12, the light pattern of the structured light SL will be deformed due to the uneven surface of the object 12. The deformed structured light SL is then reflected from the object 12, and the reflected light passes through the opening 106 to reach the sensor 104. For example, the opening 106 may include a lens, a hole, a transparent cover, and the like. The sensor 104 senses the deformation of the light pattern on the object 12 to calculate the depth of the surface of the object 12, that is, the distance between a point on the surface of the object 12 and the sensor 104. The sensor 104 may be connected to a processor (not shown in the figure) for calculating the three-dimensional feature of the object 12.

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 a light beam LB. The light source 110 can be a light emitting diode (LED), a laser diode, an edge emitting laser, a vertical-cavity surface-emitting laser (VCSEL), or any Others can emit visible or invisible (for example: infrared light (IR) or ultraviolet light (UV)) light 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 the structured light projector 100 with at least two focus states. A polarizer (not shown in the figure) can be selectively 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 sequence 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 arranged on the path of the light beam LB and before the liquid crystal lens module 120. In some embodiments, it can 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 used to generate a diffraction pattern and used to generate the structured light SL described above with reference to FIG. 1. For example, the diffractive optical element 130 may include a pattern that splits the light beam LB to multiple points, or a pattern that shapes the light beam LB into grid lines, but is not limited thereto. For simplicity, the light beam LB passing through the diffractive optical element 130 is referred to as structured light SL below. In addition, for ease of description, the x-direction and the z-direction perpendicular to each other are provided. For example, in this embodiment, the z-direction is defined as a direction perpendicular to the surface on which the light source 110 emits light.

3A to 3C show schematic cross-sectional views of various structured light projectors 200a to 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 projector 200a to 200c and the structured light projector 100 is that the structured light projector 200a to 200c includes the liquid crystal lens unit 122 and the solid lens 124 but does not include the liquid crystal lens module 120. In some embodiments, the combination of the liquid crystal lens unit 122 and the solid lens 124 can be used as the liquid crystal lens module 120 of FIG. 2.

3A, the solid lens 124 is disposed on the path of the light beam LB and 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 on the solid lens 124 and the diffractive optical element 130 between. In FIG. 3B, the solid 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 diffractive optical element 130 on the side 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 arranged 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 arranged on the path of the light beam LB and is located between the solid-state lens 124 and the light source 110 .

In some embodiments, the solid lens 124 may be a single lens or a combination with multiple lenses, which defines the main focal length of the structured light projector 200a. In some embodiments, the solid-state lens 124 collimates the light beam before the light beam LB 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 controlling the orientation of liquid crystal molecules (not shown in the figure) in the liquid crystal lens unit 122 by applying a voltage.

4A to FIG. 8 disclose some embodiments of the liquid crystal lens module that can be used as the liquid crystal lens module 120 in 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 invention. The liquid crystal lens module 220 includes a first substrate 224a, a second substrate 224b, 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. The first electrode 230a is disposed on the first substrate 224a between the liquid crystal layer 222 and the first substrate 224a. Meanwhile, 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 an alignment film 232 respectively disposed on the first electrode 230 a and the second electrode 230 b and contacting 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 and polar angles 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 long axis of the liquid crystal molecules 226 on the plane perpendicular to the z-direction and a fixed axis (For example: along the x-direction) between the angles. The material used for the alignment film 232 in this embodiment may be a polymer (for example: 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 the thickest in the middle part. 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 supply 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 the 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 connected to the power supply 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 supply 228, the liquid crystal layer 222 has a first effective refractive index so that when combined with the convex shape of the liquid crystal lens module 220, the 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 arrangement 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 convex When the type is combined, the light entering along the z-direction will be focused to the second focal length F2. Therefore, the focal length of the liquid crystal lens module 220 can be controlled by turning the power supply 228 on or off.

FIG. 5 is a schematic cross-sectional view of a liquid crystal lens module 320 according to an embodiment of the 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, and alignment films 232a and 232b, and its arrangement is similar to 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 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 the optical characteristics of a diffractive lens. For example, the step shape of the second electrode 230b and the second alignment film 232b may be designed such that the liquid crystal layer 222 following the step shape may 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.

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

In FIG. 6A, the liquid crystal lens module 420a includes a first substrate 224a, a second substrate 224b, a liquid crystal layer 222, a second electrode 230b, and alignment films 232a and 232b, and its arrangement is similar to the liquid crystal lens module 220. 6A, the difference between the liquid crystal lens module 420a and the liquid crystal lens module 220 is 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, and the first electrode 230a is a patterned electrode having a gap or an opening therebetween and is disposed on the first substrate 224a and the liquid crystal The layer 222 is on the opposite side, and the first alignment film 232a is flat. Therefore, the liquid crystal layer 222 of this embodiment 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, which causes 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 pattern other than the pattern shown in FIG. 6A. The uneven distribution of the liquid crystal orientation produces a distributed refractive index. Depending on the distribution of refractive index, the liquid crystal lens module 420a may be a refractive lens or a diffractive lens.

6B is a schematic cross-sectional view of a liquid crystal lens module 420b according to an embodiment of the 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 far 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 makes it possible to further control the voltage distribution in the liquid crystal layer 222 to provide further fine-tuning of the optical properties. Depending on the distribution of refractive index, the liquid crystal lens module 420b may be a refractive lens or a diffractive lens.

FIG. 7 is a schematic cross-sectional view of a liquid crystal lens module 520 according to an embodiment of the 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, and 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 electrode 530b is separated by an insulator disposed therebetween, for example, separated by a part 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 224a and the second substrate 224b. 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 intervals 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 can also be separately connected to other power sources to further control the liquid crystal molecules. Depending on the distribution of refractive index, the liquid crystal lens module 520 may be a refractive lens or a diffractive lens.

FIG. 8 is a schematic cross-sectional view of a liquid crystal lens module 620 according to an embodiment of the 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 a first alignment film 232a. High-resistance material layer 640. The high-resistance material layer 640 provides a continuously varying voltage between the electrodes, thereby improving the quality of the formed image. The sheet resistance of the high-impedance 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-impedance 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.

FIG. 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 the 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 Figure 9, the polar angle of the liquid crystal molecules is controlled by the alignment film to form a Pancharatnam-Berry phase liquid crystal lens. Other liquid crystal lenses can be formed by alignment films with 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 invention. In FIGS. 10A and 10B, the liquid crystal lens module 720 includes a liquid crystal cell 722 and an anisotropic lens (anisotropic lens) 724, wherein the liquid crystal cell 722 is connected to a power source 228. In the liquid crystal lens module 720, the liquid crystal cell 722 is 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, 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 opened, the liquid crystal cell acts as a half-wave plate to change the polarization of incident light. The anisotropic lens 724 is provided on the light 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. When crossing, the refractive index is the smallest. Because the opening and closing of the liquid crystal cell 722 changes the polarization of light, the focal length of the anisotropic lens also changes. The liquid crystal lens module 720 is also called a passive liquid crystal lens because the liquid crystal cell does not actively focus or diverge 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 can 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, and a programmable logic device (PLD). ) Or other similar elements, or combinations of the elements, are not particularly limited by the present invention. In addition, in some embodiments, each function of the controller can be implemented by multiple codes. These codes will be stored in memory or non-transitory storage media so that these codes can be executed by the controller. Or, in an embodiment, each function of the controller may be implemented by one or more circuits. The present invention is not intended to limit whether each function of the controller is realized by software or hardware.

By providing a liquid crystal lens with an adjustable zoom in the structured light projector, the focus range of the structured light projector becomes adjustable and can cover a wider range, making it possible to measure features at different distances on a 3D object. In addition, compared with the traditional voice coil motor (VCM) in the focusing lens, the optical projector using the liquid crystal lens has the advantages of smaller size and low power consumption. Therefore, the optical projector of the present invention can be easily installed in a mobile electronic device, providing the mobile electronic device with 3D sensing features.

11A and 11B are schematic cross-sectional views of the adjustable light projector in the structured light mode and the 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 (in FIGS. 11A and 11B are multiple light sources 810 as an example), a fixed optical phase modulator 820, and Adjustable LCD panel 900 and a driver 830. These light sources 810 are used to emit multiple light beams 811 (in FIGS. 11A and 11B, one light source 810 is schematically shown as an example of emitting one light beam 811 ). In this embodiment, the light sources 810 are multiple light-emitting areas (or light-emitting points) of a vertical cavity surface-emitting laser, or multiple edge-emitting lasers (EEL), respectively. Or multiple other suitable laser transmitters or laser diodes, respectively.

The fixed optical phase modulator 820 is disposed on the path of the light beam 811 and 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 arranged 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 show 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 may be 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 are 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 in between the structured light and the flood light. Switch between. Specifically, the optical spatial phase distribution of the liquid crystal layer 930 changes as the voltage difference changes, 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 is similar to a transparent layer. Therefore, the structured light from the fixed optical phase modulator 820 will penetrate the transparent layer and still be a structured light, and the adjustable 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 refractive index distribution of the liquid crystal layer 930 is not uniform, so the liquid crystal layer 930 is similar to a lens array. Therefore, the structured light from the fixed optical phase modulator 820 is converted into a floodlight by the lens array, and the adjustable light projector 800 is in a floodlight mode. The structured light can be irradiated on the object to form a light pattern with multiple dots, stripes or other suitable patterns on the object. This floodlight can illuminate the object evenly.

In the adjustable light projector of this embodiment, the adjustable liquid crystal panel 900 is used to switch the beam 811 between structured light and floodlight. Therefore, this embodiment integrates the floodlight 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 floodlight. 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 (it is a transparent layer at this time) and Still a flood. When the voltage difference between the first electrode layer 940 and the second electrode layer 950 is not zero, the floodlight from the fixed optical phase modulator 820 is covered by the liquid crystal layer 930 (in this case, it is an optical layer similar to a lens array) Converted into a structured light.

In 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 separate the liquid crystal layer 930 Switch to two refractive index distributions, and then respectively switch the collimated light from the fixed optical phase modulator 820 into a structured light and a flood light.

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. 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 less than 1 mm. The shape of the micro-opening 942 includes a circle (as shown in FIG. 12A), a rectangle (as shown in FIG. 12B), a square, a hexagon (as shown in FIG. 12C), other geometric shapes, and other irregular shapes Or a combination.

13A, 13B, and 13C are schematic top views of other three variations of the first electrode layer in FIG. 12A. Referring to FIGS. 12A, 13A, 13B, and 13C, the size and position of the micro-opening 942 can be regular or irregular. For example, in FIG. 12A, the sizes of the micro-openings 942 are equal to each other, and the positions of the micro-openings 942 are regular. In FIG. 13A, the sizes of the micro-openings 942 are equal to each other, and the positions of the micro-openings 942 are irregular. In FIG. 13B, the micro-openings 942 have different sizes, and the positions of the micro-openings 942 are regular. In FIG. 13C, the micro-openings 942 have different sizes, and the positions of the micro-openings 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. 14A, the adjustable liquid crystal panel 900 has a liquid crystal layer 930, which includes a polymer network liquid crystal (PNLC), which includes liquid crystal molecules 932 and a polymer network 934. 14B, the adjustable liquid crystal panel 900a may have a liquid crystal layer 930a, which includes a nematic liquid crystal (nematic liquid crystal). 14C, the adjustable liquid crystal panel 900b may have a liquid crystal layer 930b, which includes a polymer dispersed liquid crystal (PDLC), which includes liquid crystal molecules 932b and a polymer 934b.

15A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the invention. Please refer 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 invention. 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 invention. Please refer 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 shows 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 alignment 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 has an irregular spatial distribution. In other words, the azimuth angles of the alignment in different regions of the first alignment layer 960a or the second alignment layer 970a are different from each other. Different orientations and different azimuth angles can refract or diffract the light beam 811 from the light source 810 in different polarization directions.

FIG. 17A is a schematic cross-sectional view of an adjustable light projector using the alignment layer of FIG. 16B. FIG. 17B is a schematic top view of the spot area and the alignment layer in FIG. 17A. Referring to FIGS. 17A and 17B, the adjustable light projector 800c 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 irregular spatial distribution of the first alignment layer 960a and the second alignment layer 970a have a locally identical alignment area R1 that is smaller than the fixed alignment area R1 on the adjustable liquid crystal panel 900c. A spot area R2 irradiated by the light beam 811 of the optical phase modulator 820. Therefore, the light beams 811 having various polarization directions can be refracted or diffracted by the liquid crystal layer 900c.

18A, 18B, and 18C show schematic cross-sectional views of an adjustable liquid crystal panel and the voltage difference applied to the liquid crystal layer in three different modes. Please refer to FIGS. 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 (such as 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 for scattering The light beam 811 from the fixed optical phase modulator 820.

In 18B, when the voltage difference between the first electrode layer 940 and the second electrode layer 950 is a high-frequency AC voltage (this "high frequency" is, for example, a frequency greater than 1 kHz and less than or equal to 60 kHz), the The voltage difference ΔV of the liquid crystal layer 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, and is used to slightly scatter and condense the light beam from the fixed optical phase modulator 820 811.

In 18C, when the voltage difference between the first electrode layer 940 and the second electrode layer 950 is a low-frequency alternating voltage (this "low frequency" is, for example, a frequency greater than or equal to 60 Hz and less than or equal to 1 kHz), the liquid crystal is applied The voltage difference ΔV of the layer 930 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 aforementioned "high frequency" is greater than the aforementioned "low frequency".

FIG. 19A is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the present invention, and FIG. 19B is a schematic top view of the first substrate in FIG. 19A. 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 this embodiment, both the first electrode layer 940g and the second electrode layer 950g are disposed on the same substrate (for example, 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 micro patterns 942g, and the second electrode layer 950g includes a plurality of conductive micro patterns 952g. The conductive micropatterns 942g and the conductive micropatterns 952g are alternately arranged along one direction (for example, 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 the conductive micropattern 942g and the conductive micropattern 952g may extend along 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 between the first electrode layer 940g and the first substrate 910, and the first electrode layer 940g and the second electrode layer 950 are disposed between the insulating layer 990 to insulate each other. 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 invention. Please refer 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 Same as 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 invention. Please refer 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 this embodiment includes a first electrode layer 940g and a second electrode layer 950g as shown in FIG. 19A, which are arranged on the first substrate 910, and includes the image shown on the second substrate 920. The first electrode layer 940g and the second electrode layer 950 shown in 20A. In other words, the first substrate 910 side has a lateral electric field switching electrode design, and the second substrate 920 side has a fringe field switching electrode design. However, in other embodiments, both the first substrate 910 side and the second substrate 920 side may have electrode designs for lateral electric field switching, or the first substrate 210 side and the second substrate 920 side may both have fringe field switching electrodes. design.

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

23A and FIG. 23B are schematic cross-sectional views of the adjustable light projector in the structured light mode and the flood light mode, respectively, according to another embodiment of the present invention. Please refer to FIGS. 23A and 23B. The adjustable light projector 8001 of this embodiment is similar to the adjustable light projector 800, and the main differences between the two are as follows. In the adjustable light projector 8001 of this embodiment, the adjustable liquid crystal panel 9001 is used to switch between a plurality of states (FIG. 23A and FIG. 23B schematically show two states respectively), and these states include a lens array In the state (as shown in FIG. 23B), the adjustable liquid crystal panel 9001 in the lens array state includes a lens array including a plurality of lenses 905 arranged in an array. In this embodiment, the lenses 905 are a plurality of Pancharatnam-Berry phase liquid crystal lenses arranged in an array, and the alignment of the liquid crystal molecules of the liquid crystal layer 9301 of each lens 905 is as shown in FIG. 9, which can be It is achieved by the alignment layers 960l and 970l.

In the structured light mode, no voltage difference is applied between the first electrode layer 940 and the second electrode layer 950 of the adjustable liquid crystal panel 900l, and the adjustable liquid crystal panel 900l is like a transparent plate, so it comes from a fixed optical phase modulator The structured light of 820 is maintained and penetrates the adjustable liquid crystal panel 900l. In addition, in the flood mode, the driver 830 applies a voltage difference between the first electrode layer 940 and the second electrode layer 950, and the adjustable liquid crystal panel 9001 is like a lens array, and will come from the fixed optical phase modulator 820 The structured light is converted to flood light.

The adjustable liquid crystal panel 9001 can also be used to replace the liquid crystal lens unit 122 of FIGS. 3A, 3B, and 3C to change the focal length.

Please refer to FIGS. 23A and 23B again. In this embodiment, the lens array covers the entire adjustable liquid crystal panel 900l. However, in other embodiments, the lens array can be located in a region of interest of the adjustable liquid crystal panel 9001, which can be formed by at least one of the first electrode layer 940 and the second electrode layer 950 The pattern design and the appropriate voltage difference distribution applied between them are achieved.

In an embodiment, the driver 830 is used to change the focal length of each of the lenses 905 of the lens array. In an embodiment, the driver 830 is used to change the position of each of the lenses 905 of the lens array. In an embodiment, the driver 830 is used to change the size of each of the lenses 905 of the lens array. In an embodiment, the driver 830 is used to change at least one of the focal length, position, and size of each of the lenses 905 of the lens array.

In this embodiment, the adjustable liquid crystal panel 9001 is a transmissive liquid crystal panel and is arranged on the path of the light beam 811 from the fixed optical phase modulator 820. However, in other embodiments, the fixed optical phase modulator 820 may be configured on the path of the light beam 811 from the adjustable liquid crystal panel 9001 (as shown in FIG. 22).

24 is a schematic cross-sectional view of an adjustable light projector according to another embodiment of the invention. Please refer to FIG. 24. The adjustable light projector 800m of this embodiment is similar to the adjustable light projector 8001 of FIGS. 23A and 23B, and the main differences between the two are as follows. In the adjustable light projector 800m of this embodiment, the adjustable liquid crystal panel 900m is a reflective liquid crystal panel that reflects the light beam 811 from the light source 810 to the fixed optical phase modulator 820. However, in other embodiments, the adjustable liquid crystal panel 900m can reflect the light beam 811 from the fixed optical phase modulator 820 to the object 12 (as shown in FIG. 1).

In this embodiment, the adjustable liquid crystal panel 900m may include the adjustable liquid crystal panel 900l and a reflector 906 disposed thereon, so the light beam 811 can pass through the liquid crystal layer of the adjustable liquid crystal panel 900m twice. The reflector 906 can be a reflective film coated on the substrate of the adjustable liquid crystal panel 900l, or can be a reflective sheet disposed on the substrate of the adjustable liquid crystal panel 900l, and the reflector 906 can be on the inside or outside of the substrate superior.

In this embodiment, since the light beam 811 passes through the liquid crystal layer of the adjustable liquid crystal panel 900 m twice, the optical path length of the light beam 811 in the liquid crystal layer becomes twice. Therefore, the thickness of the liquid crystal layer of the adjustable liquid crystal panel 900m can be reduced. Generally speaking, the response time of the liquid crystal is inversely squared to the thickness of the liquid crystal layer, so the 900 m response time of the adjustable liquid crystal panel can be effectively shortened.

In this embodiment, the solid lens 124 is arranged on the path of the light beam 811. However, in other embodiments, the solid lens 124 may not be used.

In summary, in the adjustable light projector of the embodiment of the present invention, the adjustable liquid crystal panel is used to switch the beam between structured light and floodlight. Therefore, the embodiment of the present invention combines the floodlight 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 aforementioned multiple adjustable light projectors can replace any of the aforementioned multiple structured light projectors in the optical sensing device to form an optical sensing device with both floodlight recognition and structured light recognition functions. In the flood recognition function, the sensor can sense an 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 human face is the face of the user of an electronic device.

Although the present invention has been disclosed in the above 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. The scope of protection of the present invention shall be subject to those defined by the attached patent scope.

10: Optical sensing device 12: Object 100, 200a, 200b, 200c: structured light projector 104: Sensor 106: open 110: light source 120, 220, 320, 420a, 420b, 520, 620, 720: LCD lens module 122: liquid crystal lens unit 124: solid lens 130: Diffraction optics 222: liquid crystal layer 224a: first substrate 224b: second substrate 226: Liquid Crystal Molecules 228, 428a, 428b: power supply 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: Electrode 530b: Floating electrode 640: High-impedance material layer 722: LCD unit 724: Anisotropic lens 800, 800c, 800k, 800l, 800m: 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, 900l, 900m: adjustable LCD panel 905: lens 906: reflector 910: The first substrate 920: second substrate 930, 930a, 930b, 930l: liquid crystal layer 932, 932b: Liquid crystal molecules 934: polymer network 934b: polymer 940, 940g: first electrode layer 942: Micro-opening 942g, 952g: conductive micro pattern 950, 950g, 950h, 950j: second electrode layer 960, 960a, 960d: the first alignment layer 960l, 970l: alignment layer 970, 970a, 970d: second alignment layer 980: high impedance layer 990: Insulation layer A1: Optical axis D: Maximum diameter F1, F2: Focal length L1: Orientation LB: beam LP: Polarized light R1: Locally same alignment area R2: Spot area SL: structured light ΔV: Voltage difference

FIG. 1 is a schematic diagram of an optical sensing device according to an embodiment of the 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 the 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. FIG. 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 11B are schematic cross-sectional views of the adjustable light projector in the structured light mode and the 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 in FIG. 12A. FIG. 14A is a schematic cross-sectional view of the adjustable liquid crystal panel of FIG. 11A. 14B and 14C show 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 invention. 15B is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the invention. 15C is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the invention. Fig. 16A shows 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 an adjustable light projector using the alignment layer of FIG. 16B. FIG. 17B is a schematic top view of the spot area and the alignment layer in FIG. 17A. 18A, 18B, and 18C show schematic cross-sectional views of an adjustable liquid crystal panel and the voltage difference 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 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 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 invention. 21B is a schematic cross-sectional view of an adjustable liquid crystal panel according to another embodiment of the invention. 22 is a schematic cross-sectional view of an adjustable light projector according to another embodiment of the invention. 23A and FIG. 23B are schematic cross-sectional views of the adjustable light projector in the structured light mode and the flood light mode, respectively, according to another embodiment of the present invention. 24 is a schematic cross-sectional view of an adjustable light projector according to another embodiment of the invention.

800l: adjustable light projector

810: light source

811: beam

820: fixed optical phase modulator

830: drive

900l: Adjustable LCD panel

905: lens

910: The first substrate

920: second substrate

930l: liquid crystal layer

940: first electrode layer

950: second electrode layer

960l, 970l: alignment layer

980: high impedance layer

Claims (13)

An adjustable light projector includes: a light source for emitting a light beam; a fixed optical phase modulator arranged on the path of the light beam and used for modulating the phase of the light beam; and an adjustable liquid crystal panel configured On the path of the light beam and used to switch between a plurality of states, wherein the states include a lens array state, and the adjustable liquid crystal panel in the lens array state includes a lens array; and a driver, It is electrically connected to the adjustable liquid crystal panel and used to change the position of each of the lenses of the lens array. The adjustable light projector according to claim 1, wherein the lens array is located in an area of the adjustable liquid crystal panel corresponding to the fixed optical phase modulator. The adjustable light projector according to claim 1, wherein the driver is used to change the focal length of each of the lenses of the lens array. The adjustable light projector according to claim 1, wherein the driver is used to change the size of each of the lenses of the lens array. The adjustable light projector according to claim 1, wherein the driver is used to change the focal length and size of each of the lenses of the lens array. The adjustable light projector according to claim 1, wherein the fixed optical phase modulator is used to modulate the beam into structured light or floodlight. The adjustable light projector according to claim 1, wherein the fixed optical phase modulator is used to modulate the light beam into a collimated light. The adjustable light projector according to claim 1, wherein the optical spatial phase distribution of the liquid crystal layer of the adjustable liquid crystal panel changes as the voltage difference between the plurality of electrode layers of the adjustable liquid crystal panel changes to Switch the beam between structured light and flood light. The adjustable light projector according to claim 1, wherein the lens array includes a plurality of Berry phase liquid crystal lenses arranged in an array. The adjustable light projector according to claim 1, wherein the adjustable liquid crystal panel is a transmissive liquid crystal panel. The adjustable light projector according to claim 1, wherein the adjustable liquid crystal panel is a reflective liquid crystal panel. The adjustable light projector according to claim 1, wherein the fixed optical phase modulator is arranged on the path of the light beam from the adjustable liquid crystal panel. The adjustable light projector according to claim 1, wherein the adjustable liquid crystal panel is arranged on the path of the light beam from the fixed optical phase modulator.

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