Illumination light modulator, illumination device, and projection device

Abstract

This application provides an illumination light modulator, an illumination device, and a projection device, relating to the field of optical technology. The light modulator has multiple pixel regions, each containing multiple pixel units. The light modulator includes: a power supply layer comprising multiple mutually insulated power supply units; and an electrode layer comprising multiple spaced-apart electrode units, each electrode unit corresponding to a pixel region. Each electrode unit and power supply unit are electrically connected and correspond one-to-one. The power supply unit inputs a voltage to its corresponding electrode unit, and the electrode unit controls the direction or polarization state of light incident on the pixel region corresponding to that electrode unit from the illumination light modulator based on the voltage. The state changes of all pixel units within each pixel region are consistent. This invention achieves the control of multiple pixel units by a single electrode unit at the underlying circuit level rather than the control signal level, resulting in low cost and reliable performance.

Description

Technical Field

[0001] This application relates to the field of optical technology, and more particularly to an illumination light modulator, illumination device, and projection device. Background Technology

[0002] With societal progress, lighting devices have become indispensable products. However, existing lighting devices typically cannot change the direction of light emission by controlling their internal structure. To change the direction of light emission, the position of the lighting device must be adjusted, or an additional light path deflector (such as a movable reflector) must be installed. In the field of automotive lighting, the Adaptive Frontlighting System (AFS) technology is known. It uses a horizontal drive motor and a vertical adjustment motor to adjust the horizontal and vertical angles of the headlights respectively to achieve different lighting functions (such as urban lighting, cornering lighting, and highway lighting). This technology uses the entire headlight module as the adjustment object, resulting in a large size, high power consumption, high requirements for mechanical reliability, and very inflexible adjustment. It can only achieve a few preferred lighting modes and has no room for upgrades or modifications.

[0003] Researchers have proposed combining a color wheel with a GOBO board to create different emission patterns through the rotation of the color wheel, thus addressing diverse lighting needs. However, this solution still utilizes a color wheel requiring a mechanical motor, which is unsuitable for applications demanding high mechanical reliability. Furthermore, the mechanical motor also requires a control chip, adding to both cost and power consumption.

[0004] In high-end automotive headlights, there are already products using LCD (Liquid Crystal Device) technology and pre-research products using DMD (Digital Micromirror Device) technology. These products apply LCD / DMD display chips from the projection display field to lighting to achieve pixel-level image illumination. However, these products have complex structures, leading to high manufacturing costs and low product yields. Especially when used as optical switches, the redundancy in pixel-level modulation capabilities makes the system less robust. Summary of the Invention

[0005] This application provides an illumination light modulator, an illumination device, and a projection device to improve the above-mentioned problems.

[0006] In a first aspect, an illumination light modulator is provided, having multiple pixel regions, each pixel region comprising multiple pixel units. The illumination light modulator includes: a power supply layer comprising multiple power supply units that are mutually insulated; and an electrode layer comprising multiple electrode units spaced apart, each electrode unit corresponding to a pixel region. The electrode units and power supply units are one-to-one and electrically connected. The power supply units are used to input a voltage to their corresponding electrode units, and the electrode units are used to control the emission direction or polarization state of light incident on the pixel region corresponding to the electrode unit from the illumination light modulator according to the voltage. The state changes of each pixel unit contained in each pixel region are consistent.

[0007] This application provides an illumination light modulator, which includes a power supply layer and an electrode layer. The emission direction of light emitted from the illumination light modulator can be changed by controlling the voltage input to the electrode units; alternatively, the polarization state of the light emitted from the illumination light modulator can be changed by controlling the voltage input to the electrode units, thereby altering the brightness of the emitted light. Furthermore, since each electrode unit corresponds to a pixel region, compared to conventional light modulators, this application embodiment has fewer power supply units and fewer signals used to control the electrode units, reducing the operating memory of the illumination light modulator. Moreover, by providing a power supply layer for each pixel unit, this application eliminates the need to control the state of light emitted from that pixel unit through the switching of multiple transistors, thus avoiding the complexity of interconnecting multiple transistors and the need to fabricate a multi-layer structure to accommodate large-scale circuit components. Therefore, this application simplifies the structure of the illumination light modulator and reduces its thickness. Meanwhile, compared to mechanical control methods, the embodiments of this application can change the emission direction or polarization state of light through electronic control, which is more intelligent and can avoid the mechanical reliability and noise problems of mechanical control technology, as well as avoid the additional cost and power consumption of mechanical control chips.

[0008] In a second aspect, a lighting device is provided, including a light source, a lens, and the lighting light modulator described in the first aspect. The lighting light modulator receives and emits light emitted from the light source, and the lens is disposed on the light-emitting side of the lighting light modulator. The lens includes at least a first lens and a second lens, and a plurality of electrode units include at least a first electrode unit and a second electrode unit. The first lens is correspondingly disposed with the first electrode unit, and the second lens is correspondingly disposed with the second electrode unit. When the first electrode unit is in an active state, the light emitted from the light source is modulated by the lighting light modulator and then emitted as a first beam by the first lens. When the second electrode unit is in an active state, the light emitted from the light source is modulated by the lighting light modulator and then emitted as a second beam by the second lens. The lighting device can emit either the first beam or the second beam, or simultaneously emit both the first beam and the second beam, by independently controlling the first electrode unit and the second electrode unit.

[0009] This application provides a lighting device, including a light source, a lens, and an illumination light modulator. The illumination light modulator includes a power supply layer and an electrode layer. Light emitted from the light source can illuminate multiple electrode units on the electrode layer, be reflected by the electrode units, exit from the illumination light modulator, and enter the lens. After being modulated by the lens, it is used for illumination. Furthermore, the emission direction of the light emitted from the illumination light modulator can be changed by controlling the voltage input to the electrode units; or, the polarization state of the light emitted from the illumination light modulator can be changed by controlling the voltage input to the electrode units, thereby changing the brightness of the emitted light. Simultaneously, since each electrode unit corresponds to a pixel region containing multiple pixel units, compared to traditional illumination light modulators, this application embodiment has fewer power supply units and fewer signals used to control the electrode units, reducing the operating memory of the illumination light modulator. Moreover, by providing a power supply layer for each pixel unit, this application eliminates the need for switching multiple transistors to control the state of the light emitted from that pixel unit, thus simplifying the structure of the illumination light modulator and reducing its thickness. Meanwhile, compared to mechanical control methods, the embodiments of this application can change the emission direction or polarization state of light through electronic control, which is more intelligent and can avoid the mechanical reliability and noise problems of mechanical control technology, as well as avoid additional cost and power consumption issues of control chips.

[0010] Thirdly, a projection device is provided, including a light source, an image light modulator, and the illumination light modulator described in the first aspect. The illumination light modulator receives light emitted from the light source, modulates the illumination light, and then emits it. The light emitted from the illumination light modulator is incident on the image light modulator, modulated by the image light modulator, and emitted as image light.

[0011] This application provides a projection device, which includes a light source, an image light modulator, and an illumination light modulator. The illumination light modulator includes a power supply layer and an electrode layer. Light emitted from the light source can illuminate multiple electrode units on the electrode layer, and after reflection by the electrode units, it exits from the illumination light modulator and enters the image light modulator. After being modulated by the image light modulator, it is used to display an image. Furthermore, the emission direction of the light emitted from the illumination light modulator can be changed by controlling the magnitude of the voltage input to the electrode units; or, the polarization state of the light emitted from the illumination light modulator can be changed by controlling the magnitude of the voltage input to the electrode units, thereby changing the brightness of the emitted light. Meanwhile, since each electrode unit corresponds to a pixel region containing multiple pixel units, compared to traditional illumination light modulators, the number of power supply units in this application embodiment is less, and the number of signals used to control the electrode units is also less, which can reduce the working memory of the illumination light modulator; furthermore, in each pixel unit, this application sets a power supply layer, eliminating the need to control the state of the light emitted from that pixel unit through the switching of multiple transistors, thus simplifying the structure of the illumination light modulator and reducing its thickness.

[0012] Building upon this, embodiments of this application can also utilize a fixed color conversion element to replace the existing color wheel, replacing mechanical light color adjustment with electrical light color adjustment. Compared to the complex and thick motor / color wheel, the color conversion element of this application is easier to construct and can reduce the thickness of the projection device. Simultaneously, it saves the motor and motor control chip required to drive the color wheel, and also saves the electrical energy required to drive the color wheel. Furthermore, this application can leverage Moore's Law to achieve mass production and cost reduction, while mechanical components such as motors / color wheels do not follow Moore's Law and are excessively expensive. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a schematic diagram illustrating the principle structure of the illumination light modulator of this application;

[0015] Figure 2 This is a schematic diagram of the illumination light modulator provided in Embodiment 1 of this application;

[0016] Figure 3 This is a schematic diagram of the side structure of the illumination light modulator provided in Embodiment 1 of this application;

[0017] Figure 4 This is a schematic diagram of the illumination light modulator provided in Embodiment 2 of this application;

[0018] Figure 5 This is a schematic diagram of the structure of a lighting device provided in an embodiment of this application;

[0019] Figure 6 This is a schematic diagram of the structure of a projection device provided in an embodiment of this application;

[0020] Figure 7 This is a schematic diagram of another projection device provided in an embodiment of this application.

[0021] Attached icon:

[0022] 10-Illumination light modulator; 11-Power supply layer; 111-Power supply unit; 1111-First power supply unit; 1112-Second power supply unit; 1113-Third power supply unit; 12-Electrode layer; 121-Electrode unit; 1211-Electrode subunit; 13-Liquid crystal layer; 14-Transparent electrode layer; 14'-Transparent electrode layer power supply unit; 15-Lower alignment layer; 16-Upper alignment layer; 18-Substrate; 100-Illumination device; 20-Light source; 30-Lens; 31-First lens; 32-Second lens; 33-Third lens; 200-Projection device; 40-Image light modulator; 50-Color light conversion element; 60-Relay optical element. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. It should be noted that, unless otherwise specified, the features in the embodiments of this application can be combined with each other.

[0024] The illumination light modulator of this invention is based on the working principle of traditional spatial light modulators, but differs significantly in structure and function. Structurally, it is primarily characterized by a significant simplification of the layer and circuit structures. Functionally, it primarily involves "controlling a pixel region containing multiple pixel units through a single power supply unit / electrode unit." For example, traditional spatial light modulators can be reflective phase light modulators, such as Liquid Crystal on Silicon (LCoS), transmissive phase light modulators, such as Liquid Crystal Display (LCD), or micro-electro-mechanical systems (MEMS), such as Digital Micromirror Devices (DMDs). These traditional spatial light modulators have complex circuit structures, requiring an electrode unit or switch for each pixel unit for control; they also have complex layer structures, necessitating multiple layers of circuitry and dielectric layers between the circuits to accommodate the control circuitry for so many pixel units. Utilizing these complex structures, it is possible to achieve complex functions, namely, independently controlling each pixel unit. This invention, starting from different practical purposes, breaks away from the rigid thinking of the original spatial light modulator and designs an illumination light modulator with a simpler structure, lower cost, and more convenient operation.

[0025] like Figure 1 The diagram shown is a schematic representation of the principle structure of the illumination light modulator of this application. This application provides an illumination light modulator 10, which has multiple pixel regions, each pixel region including multiple pixel units. The illumination light modulator 10 includes a power supply layer 11 and an electrode layer 12. The power supply layer 11 includes multiple mutually insulated power supply units 111 (as shown, it includes two power supply units 111, but the invention is not limited to this number; it can also have three or more). The electrode layer 12 includes multiple spaced-apart electrode units 121, each electrode unit 121 corresponding to a pixel region. The electrode units 121 and power supply units 111 are electrically connected and correspond one-to-one. The power supply unit 111 is used to input a voltage to its corresponding electrode unit 121. The electrode unit 121 is used to control the direction or polarization state of light incident on the pixel region corresponding to the electrode unit 121 from the illumination light modulator 10 according to the voltage, so that the state changes of each pixel unit contained in each pixel region are consistent. Therefore, the illumination light modulator 10 of the present invention can control multiple pixel units through a power supply unit 111 / an electrode unit 121.

[0026] Specifically, in one embodiment of the present invention, each electrode unit includes multiple electrode sub-units spaced apart and corresponding one-to-one with pixel units. Electrode sub-units belonging to the same electrode unit are conductive and connected in series (e.g., connected via conductive leads). This series circuit configuration ensures that the voltage of each electrode sub-unit controlled by one electrode unit is the same at any given time, thereby achieving consistent control of its corresponding multiple pixel units. Furthermore, compared to traditional spatial light modulators where each pixel unit has a storage unit (mainly composed of transistors, such as SRAM which typically contains 6 transistors), the pixel units of the present invention do not have a storage unit; only a voltage output terminal is required.

[0027] For the series connection of electrode subunits, each electrode subunit can be connected in series using a mesh-like electrical connection. Based on this, even if a certain electrode subunit is not connected to the power supply voltage, causing it to malfunction, the other electrode subunits in the same electrode unit can still function normally.

[0028] Apart from the conductive connection structure, the electrode subunits are separated by an insulating layer structure to keep each electrode subunit isolated from the others.

[0029] The basic inventive concept of this invention lies mainly in the control backplane circuit of the illumination light modulator 10. The specific complete structure of the illumination light modulator 10 is not limited, as long as the illumination light modulator 10 receives and emits the incident light from the light source 20 based on the above modulation principle. The illumination light modulator 10 can be either reflective (i.e., the light incident surface and the light emitting surface are the same surface) or transmissive (i.e., the light incident surface and the light emitting surface are two opposing surfaces).

[0030] In this invention, the material of the power supply unit 111 is not limited, as long as the power supply unit 111 can conduct electricity. In some embodiments, the material of the power supply unit 111 can be a metal such as copper / aluminum or a transparent conductive material such as indium tin oxide (ITO).

[0031] In this invention, the material of the electrode unit 121 is not limited, as long as the electrode unit 121 can conduct electricity. If the illumination light modulator 10 is reflective, the material of the electrode unit 121 can be metal; if the illumination light modulator 10 is transmissive, the material of the electrode unit 121 can be a transparent conductive material such as ITO.

[0032] Insulating material can be provided between different electrode subunits, or no structure can be provided between multiple electrode subunits 1211.

[0033] In some embodiments of the present invention, the power supply unit 111 can be electrically connected to the electrode unit 121 via conductive leads, and input voltage to the electrode unit 121 via the conductive leads. The conductive leads can be fabricated by deposition. In one specific embodiment, the circuit of the illumination light modulator 10 includes a metal layer, with the electrode layer and the power supply layer each being a part of this metal layer. The circuit patterns of the power supply layer and the electrode layer can be fabricated in one step using integrated circuit manufacturing processes. Compared to traditional spatial light modulators that often require 3-4 metal layers, the present invention can achieve the illumination light modulation function with only one circuit layer, greatly simplifying the process.

[0034] Based on this, the illumination light modulator 10 may also include a switch (not shown in the figure), and the power supply unit 111 can be electrically connected to its corresponding electrode unit 121 through the switch. When it is necessary to change the light emission from the illumination light modulator 10, the switch is turned on, and the power supply unit 111 inputs voltage to its corresponding electrode unit 121 through the switch; when it is not necessary to change the light emission from the illumination light modulator 10, the switch is turned off, and the power supply unit 111 no longer inputs voltage to its corresponding electrode unit 121.

[0035] In some embodiments, since each power supply unit 111 is relatively independent, the voltage input by multiple power supply units 111 to their corresponding electrode units 121 may be the same or different to meet different application requirements due to different lighting light modulation needs.

[0036] The illumination light modulator 10 may further include a main control circuit, which controls the input voltage from each power supply unit 111 to its corresponding electrode unit 121. In some embodiments, the main control circuit can control the magnitude, duty cycle, and voltage waveform of the voltage input from the power supply unit 111 to its corresponding electrode unit 121, and can also control the order in which multiple power supply units 111 input voltage to their corresponding electrode units 121.

[0037] The following describes different optical modulation structure technologies in conjunction with specific implementation methods. For common parts in the following embodiments, the descriptions of the above-mentioned implementation methods can be referred to without further elaboration, provided that they do not conflict with the technical solution of the embodiment.

[0038] Please see Figure 2 This is a schematic diagram of the illumination light modulator provided in Embodiment 1 of this application. Please refer to... Figure 3 This is a schematic diagram of the side structure of the illumination light modulator provided in Embodiment 1 of this application. Compared to Figure 1 A schematic diagram of the principle structure. Figure 2 The structure of the pixel unit and the electrode layer are presented in an exploded view. For ease of description, Figure 2 and Figure 3 Only a partial structure of the illumination light modulator is shown in each example. This illumination light modulator is a modulator based on LCoS technology.

[0039] like Figure 2 and Figure 3 As shown, the illumination light modulator 10 includes a power supply layer 11 and an electrode layer 12. The power supply layer 11 includes multiple power supply units 111, and the electrode layer 12 includes multiple electrode units 121. Each electrode unit includes multiple electrode sub-units 1211 spaced apart. One electrode sub-unit corresponds to one pixel unit, and the electrode sub-units 1211 under the same electrode unit 121 are conductive and connected in series. Figure 3 (Represented by dashed lines), specifically, it can be manifested as the electrical connection between adjacent electrode subunits 1211, for example, by connecting them through conductive leads. The illumination light modulator 10 also includes a liquid crystal layer 13 and a transparent electrode layer 14 disposed on the light-emitting side of the electrode layer 12; the electrode layer 12 is used to reflect light to the liquid crystal layer 13, and the light is modulated by the liquid crystal layer 13 and emitted from the illumination light modulator 10.

[0040] First, let's describe the backplate portion of the illumination modulator 10 in detail. For example... Figure 3 As shown ( Figure 2 (The structure is omitted here). The backplane mainly includes a circuit layer (integrated circuit structure) and a substrate 18 (e.g., single-crystal silicon or other semiconductor substrate) that carries the circuit layer. The circuit layer includes a power supply layer 11 and an electrode layer 12, which are different functional parts of the circuit layer.

[0041] In this embodiment, the electrode layer 12 is located in the pixel region below the liquid crystal layer 13, vertically corresponding to the entire pixel region composed of multiple pixel regions; the power supply layer 11 is located in the wiring area surrounding the entire pixel region. The power supply layer 11 and the electrode layer 12 are disposed on the same layer, made of the same material, and obtained through the same patterning process. In semiconductor integrated circuit technology, this type of circuit layer is usually called a metal layer. In this embodiment, the illumination light modulator 10 contains only one metal layer, with the electrode layer 12 and the power supply layer 11 each being a part of the metal layer. The electrode layer 12 and the power supply layer 11 can constitute the entire metal layer, or the metal layer can include other circuit structures in addition to the electrode layer 12 and the power supply layer 11.

[0042] In this embodiment, the backplane also includes a dielectric layer located between the circuit layer and the substrate 18, i.e., as shown in the figure. Figure 3 The structure between the intermediate electrode subunit 1211 and the substrate 18. This structure is electrically insulating. It can be understood that in other variations of this embodiment, there may be no dielectric layer, and instead, the substrate 18 may be etched directly, and then a metal layer may be deposited in the etched pattern to form a circuit layer including the power supply layer 11 and the electrode layer 12.

[0043] It is understood that in modified embodiments of this example, multiple metal layers (such as M1, M2, M3, etc.) may be included, and the power supply layer and the electrode layer may be located on different metal layers, which would require multi-layer deposition.

[0044] In terms of manufacturing processes, multiple steps are typically required, including depositing a dielectric layer on a substrate, depositing a metal layer, coating a mask layer, photolithography, etching circuit patterns, and filling the dielectric layer. The more metal layers a structure has, the more complex the process becomes, and the more difficult it is to control cost and yield. In this embodiment, the electrode layer does not require dedicated storage circuit elements or independent control circuit elements for each pixel unit. Therefore, the circuit structure is very simple, requiring only one metal layer, which greatly simplifies the structure and significantly reduces cost.

[0045] Furthermore, in this embodiment, the electrode layer 12 is preferably made of aluminum metal electrodes. On the one hand, aluminum is conductive; on the other hand, aluminum has good visible light reflectivity, which can be directly used as the reflective substrate of the illumination light modulator 10 without the need for an additional reflective layer connected to the electrode layer, achieving two benefits at once. In addition, this embodiment uses an array of multiple aluminum metal electrode sub-units to form a whole electrode unit 121. There are gaps between adjacent aluminum metal electrode sub-units that do not directly contact each other (except for the conductive circuit part). Compared with using a whole piece of aluminum electrode, the size is decomposed, which is beneficial to control the overall optical flatness by controlling the flatness of the aluminum metal electrode sub-units. Conversely, the larger the size, the more difficult it is to control the flatness. If a whole piece of aluminum metal is used as the electrode unit, the flatness at large sizes is difficult to guarantee. For the illumination light modulator, the undulation of the aluminum metal electrode unit has a great impact on the uniformity of the output light. An overall undulation of 1° will produce a large deviation at a long distance.

[0046] The structure of the light incident side of the backplate of the illumination modulator 10 will now be described in detail. Please refer again to... Figure 2 and Figure 3 Above the backplate, there are sequentially arranged a lower alignment layer 15, a liquid crystal layer 13, an upper alignment layer 16, and a transparent electrode layer 14 (such as ITO). The lower alignment layer 15 and the upper alignment layer 16 are located on opposite sides of the liquid crystal layer 13 and can be PI (polyimide) films, used to orient the liquid crystal molecules within the liquid crystal layer 13. Enclosures are also provided around the other sides of the liquid crystal layer 13 to form enclosed spaces for the liquid crystal molecules.

[0047] The transparent electrode layer 14 is connected to the transparent electrode layer power supply unit 14', which outputs voltage to the transparent electrode layer 14, thereby controlling the voltage level of the transparent electrode layer 14. Driven by the electric field formed by the electrode layer 12 and the transparent electrode layer 14, the liquid crystal molecules in the liquid crystal layer 13 have a potential difference at both ends and are deflected. Different deflection angles of the liquid crystal result in different polarization states of the light emitted from the illumination light modulator 10 after refraction by the liquid crystal.

[0048] Among them, the voltage input from the power supply unit 111 to its corresponding electrode unit 121 is different, the electric field strength between the electrode layer 12 and the transparent electrode layer 14 is different, the deflection angle of the liquid crystal is also different, the polarization state of the light is different, and with the polarization beam splitter in the application scenario, the final brightness of the light emitted from the illumination light modulator 10 is different.

[0049] In this embodiment, the output voltage amplitude of the power supply unit 111 to the electrode unit 121 can be fixed, and low level and high level can be set. By controlling the duty cycle of the high and low levels, the switching of multiple pixel units in the pixel area corresponding to the electrode unit 121 can be controlled, thereby controlling the opening or closing of the output light.

[0050] In some embodiments, the illumination light modulator 10 drives the liquid crystal to deflect in the form of a twisted nematic (TN), vertical alignment (VA), fringe field switching (FFS), in-plane switch (IPS), or advanced superdimensional switch (ADS).

[0051] The above, combined with Figure 2 and Figure 3An illumination light modulator based on an LCoS architecture modification in Embodiment 1 is described. In a modified embodiment of Embodiment 1 of the present invention, an illumination light modulator based on an LCD architecture modification is used. Since LCD and LCoS are both optical phase modulators, their working principles are basically the same. The main difference is that LCD is transmissive, while LCoS is reflective; the former uses a glass substrate, while the latter uses a silicon substrate. Furthermore, since there is no need for reflected light, transparent conductive materials can be used as the materials for the power supply layer and / or electrode layer to improve light transmittance. Of course, since there is no need to set up storage circuits under the pixel unit, even if metal is used as the material for the power supply layer and electrode layer, narrow lines can be used without having the electrode sub-unit cover almost the entire corresponding pixel unit, thus not occupying too much area and having little impact on the light beam. Based on this, when the illumination light modulator based on LCD technology is applied, it also needs to be used with a polarizer located in the upstream optical path and an analyzer located in the downstream optical path to switch the light after the polarization state change. The above describes the main technical differences between the modified embodiment of Embodiment 1 and Embodiment 1. Other technical features related to the circuit structure principle of the control backplane can be referred to the description in Embodiment 1 above, and will not be repeated here.

[0052] Please refer to Figure 4 This is a schematic diagram of the illumination light modulator provided in Embodiment 2 of this application. The difference between this embodiment and Embodiment 1 and its variations is that this embodiment is an illumination light modulator based on a microelectromechanical system (MEMS). Specifically, the structural features of the illumination light modulator in this embodiment, such as its optical structure, can refer to existing mature digital micromirror devices; the main difference lies in the circuit structure of the control backplane.

[0053] like Figure 4 As shown, the illumination light modulator 10 includes a power supply layer 11 and an electrode layer 12. The power supply layer 11 includes a plurality of mutually insulated power supply units 111. The electrode layer 12 includes a plurality of spaced-apart electrode units 121. Each electrode unit 121 contains a plurality of spaced-apart electrode sub-units 1211. The electrode sub-units 1211 contained in each electrode unit 121 are electrically connected to each other in series. Each electrode sub-unit 1211 corresponds one-to-one with a pixel unit. In this embodiment, each pixel unit corresponds to a micromirror.

[0054] Based on the working principle of the digital micromirror device, each micromirror requires three electrodes for control. According to the potential difference between the electrodes, an electromagnetic force is formed between the metal micromirror and the substrate, thereby controlling the deflection angle of the micromirror.

[0055] Therefore, in this embodiment, each electrode subunit 1211 includes a first electrode, a second electrode, and a reset metal pad arranged at intervals. Multiple first electrodes in the same electrode unit 121 are connected in series (represented by dotted lines), multiple second electrodes in the same electrode unit 121 are connected in series (represented by solid lines), and multiple reset metal pads in the same electrode unit 121 are connected in series (represented by dashed lines). The power supply unit 111 includes a first power supply unit 1111, a second power supply unit 1112, and a third power supply unit 1113. The first power supply unit 1111 inputs a first voltage to the first electrode, the second power supply unit 1112 inputs a second voltage to the second electrode, and the third power supply unit 1113 inputs a third voltage to the reset metal pad.

[0056] The reset metal pad changes its tilt direction according to the first voltage, the second voltage, and the third voltage, thereby changing the emission direction of light from the illumination light modulator 10. The change in the tilt direction of the reset metal pad alters the emission direction of the light reflected from the illumination light modulator 10.

[0057] When a first voltage is applied to the first electrode, a second voltage is applied to the second electrode, and a third voltage is applied to the reset metal pad, an electrostatic attraction will be generated on one side of the reset metal pad, causing the reset metal pad to tilt until electrostatic equilibrium is maintained.

[0058] The reset metal pad includes a metal micro-mirror that can receive light emitted from the light source and reflect the received light. The emission angle of the light from the illumination light modulator 10 changes with the tilt angle of the reset metal pad.

[0059] In some embodiments, the illumination light modulator 10 may further include an encapsulation layer disposed outside the electrode layer 12 to protect the conductive reflector 12 from moisture and oxygen ingress, which could lead to corrosion of the electrode layer 12. The encapsulation layer may include a transparent light window for light to enter and exit.

[0060] In this embodiment, the illumination light modulator 10 can be based on a low-cost, high-yield microelectromechanical system. On the one hand, the structure is relatively simple, no storage transistor backplane is required, the fabrication process is simple, and the thickness of the illumination light modulator 10 will not be increased. On the other hand, it will not consume additional power.

[0061] The following describes the application of the various lighting light modulators described above in lighting equipment. The technical features of the lighting light modulators can be referred to the descriptions of the above embodiments, and will not be repeated here.

[0062] like Figure 5As shown, this application embodiment provides a lighting device 100, which includes a light source 20, a lens 30, and a lighting light modulator 10. The lighting light modulator 10 receives and emits light emitted from the light source 20, and the lens 30 is disposed on the light-emitting side of the lighting light modulator 10. The lighting light modulator 10 can be referred to the above description. Figures 1-4 The description of the corresponding instruction manual will not be elaborated here.

[0063] In some embodiments, the lens 30 is disposed on the light-emitting side of the illumination light modulator 10. After light is emitted from the illumination light modulator 10, it can enter the lens 30. The lens 30 can modulate the received light in an imaging or non-imaging manner, and then emit it according to the user's needs. Based on this, the specific structure and function of the lens 30 are related to the purpose of the lighting device. For example, the lighting device 100 is a vehicle headlight, and the lens 30 can modulate the light emitted from the illumination light modulator 10 according to the user's needs, thereby realizing the lighting function.

[0064] Based on this, the working process of the lighting device 100 is as follows: according to the user's needs, some or all of the power supply units 111 in the power supply layer 11 are controlled to input a certain voltage value to the electrode unit 121 of the corresponding electrode layer 12, so that the light from the output state of the lighting light modulator 10 changes, and then enters the corresponding lens 30 and is projected out through the lens 30.

[0065] like Figure 5 As shown, in this embodiment, the lens 30 includes a first lens 31, a second lens 32, and a third lens 33. The electrode layer 12 contains three electrode units 121, which can be defined as a first electrode unit, a second electrode unit, and a third electrode unit. The first lens 31 is correspondingly disposed with the first electrode unit, the second lens 32 is correspondingly disposed with the second electrode unit, and the third lens 33 is correspondingly disposed with the third electrode unit. When the first electrode unit is in an active state, the light emitted from the light source is modulated by the illumination light modulator 10 and then emitted as a first beam from the first lens 31. When the second electrode unit is in an active state, the light emitted from the light source is modulated by the illumination light modulator 10 and then emitted as a second beam from the second lens 32. When the third electrode unit is in an active state, the light emitted from the light source is modulated by the illumination light modulator 10 and then emitted as a third beam from the third lens 32.

[0066] In this invention, the lighting modulator 10 is characterized by its ability to simultaneously control multiple pixel units within a single pixel region using a single electrode unit, with the pixel regions controlled by different electrode units operating independently. Therefore, by independently controlling the first electrode unit and the second electrode unit, the lighting device can emit either a first beam or a second beam, or both simultaneously. Furthermore, this approach, where a pixel region contains multiple pixel units, decomposes the size compared to a single large pixel unit. This decomposition improves overall optical performance (such as uniformity) and, by distributing and connecting the circuitry, prevents a single circuit failure from rendering the entire pixel region unusable.

[0067] In this embodiment, the lens 30 includes three sets of lenses. It can be understood that the present invention is not limited to this number of sets, as long as it can include at least two lenses (such as the first lens and the second lens) so that the regional independent modulation function of the illumination light modulator 10 can be performed.

[0068] In some embodiments, the functions of the first lens 31 and the second lens 32 may be the same or different, as long as the first lens 31 is arranged opposite to the first electrode unit and the second lens 32 is arranged opposite to the second electrode unit.

[0069] For example, the illumination distance of the first beam emitted from the first lens 31 is greater than the illumination distance of the second beam emitted from the second lens 32.

[0070] In some embodiments, the specific structure of the first lens 31 and the second lens 32 is not limited, and their structure can be designed according to the functions of the first lens 31 and the second lens 32.

[0071] For example, the first lens 31 and the second lens 32 can be separate lenses or lens groups. Light can be reflected or refracted in the lens or lens group, and then exit from the lens or lens group.

[0072] In this invention, the purpose of the lighting device 100 is not limited. The lighting device 100 can be a vehicle headlight, a searchlight, an industrial lighting lamp, etc.

[0073] In this embodiment of the application, the lighting device can be used as a vehicle headlight to achieve illumination at different distances.

[0074] Regarding the control of the lighting light modulator 10 in the lighting device 100, in this embodiment, taking the lighting light modulator 10 including a liquid crystal layer 13 and a transparent electrode layer 14 as an example, the power supply unit 111 is controlled to input voltage to its corresponding electrode unit 121, and the power supply unit 14' of the transparent electrode layer is controlled to apply a common voltage to the transparent electrode layer 14. When there is a potential difference between the transparent electrode layer 14 and the electrode layer 12, an electric field is formed between the electrode layer 12 and the transparent electrode layer 14. Driven by the electric field, the liquid crystal in the liquid crystal layer 13 is deflected, and the light reflected by the electrode layer 12 is refracted when passing through the liquid crystal. Specifically, different voltages input by the power supply unit 111 to its corresponding electrode unit 121 result in different electric field strengths between the electrode layer 12 and the transparent electrode layer 14, different deflection angles of the liquid crystal, different polarization states of the light, and ultimately different brightness of the light emitted from the lighting light modulator 10. Subsequently, the light emitted from the illumination modulator 10 enters the corresponding lens 30, is modulated by the lens in an imaging or non-imaging manner, and then exits from the lens 30 to achieve illumination. When the voltage difference between a certain electrode unit 121 and the transparent electrode layer 14 is less than a threshold, the polarization state of the emitted light is the same as that of the incident light. In this case, this part of the light will be returned to the light source under the action of, for example, a polarizing beam splitter (not shown in the figure), so that the corresponding lens does not emit light.

[0075] In a modified embodiment of the lighting device in this example, taking the lighting light modulator 10 as a MEMS-based light modulator, by controlling the voltage of different electrode units, the tilt angle of the micro-mirrors of multiple pixel units contained in the pixel area corresponding to the electrode unit can be controlled, thereby controlling the angle of the light emitted from the lighting light modulator 10 and determining whether different areas are in a lit state or a closed state.

[0076] In some embodiments, the light source 20 can emit light of various colors as needed, such as white light, yellow light, or even infrared light (for detection illumination). The type of light source 20 can be an incandescent lamp, a laser light source, an LED light source, a laser fluorescent light source, etc. The intensity of the light emitted by the light source 20 can be changed according to actual needs to achieve different levels of illumination.

[0077] The following describes the application of the various illumination light modulators described above in projection equipment. The technical characteristics of the illumination light modulators can be found above. Figures 1-4 The description of the corresponding instruction manual will not be repeated here.

[0078] like Figure 6The diagram shown is a schematic diagram of the structure of a projection device provided in an embodiment of this application. The projection device 200 includes a light source 20, an image light modulator 40, and an illumination light modulator 10. The illumination light modulator 10 receives the light emitted by the light source 20, modulates the illumination light, and then emits it. The light emitted from the illumination light modulator 10 is incident on the image light modulator 40, modulated by the image light modulator 40, and then emitted as image light.

[0079] Based on this, the projection device 200 may also include a screen and a projection lens disposed on the light-emitting side of the image light modulator 40.

[0080] When the illumination light modulator 10 is applied to a projection device, the illumination light modulator 10 can provide illumination light for display to the image light modulator 40. After the display light is modulated by the image light modulator 40, a specific image can be displayed. After the displayed image is passed through the projection lens, an image display can be achieved.

[0081] Based on this, the working process of the projection device 200 is as follows: according to the user's needs, the main control circuit controls the brightness of the illumination light emitted from the corresponding pixel area by controlling different electrode units. The illumination light emitted from the pixel area is mapped to the image light modulator 40, and the image light modulator 40 modulates it according to the image signal to obtain an image.

[0082] Although Figure 6 The illumination light modulator 10 shown is a simplified structure based on the LCoS technology architecture. It can be understood that, for the purpose of controlling the regional brightness of the illumination light, the technical architecture of the illumination light modulator 10 can be replaced with a simplified structure of the LCD technology architecture or a simplified structure of the digital micromirror device technology architecture as described in the above embodiments.

[0083] In some embodiments, when the illumination light modulator 10 is applied to the projection device 200, the light emitted by the light source 20 can be white light. The type of light source 20 can be a bulb light source, an LED light source, a pure laser light source, a laser fluorescent light source, or a combination of the aforementioned light sources.

[0084] In this embodiment, the image light modulator can be an LCD, LCoS, DMD, etc.

[0085] Please see Figure 7 This is a schematic diagram of another projection device provided in an embodiment of the present invention. The projection device 200 includes a light source 20, an illumination light modulator 10, a color light conversion element 50, a relay optical element 60, and an image light modulator 40. The technical features of the illumination light modulator 10 can be found above. Figures 1-4 The description of the corresponding instruction manual will not be repeated here.

[0086] The illumination light modulator 10 receives light emitted from the light source 20, modulates it, and then emits it. The light emitted from the illumination light modulator 10 is incident on the image light modulator 40, modulated by the image light modulator 40, and then emitted as image light. A color conversion element 50 and a relay optical element 60 are disposed between the illumination light modulator 10 and the image light modulator 40. The color conversion element 50 includes multiple color zones, which correspond to the electrode units in the illumination light modulator 10. The light emitted from the illumination light modulator 10 is converted into spatially separated temporally colored beams by the color conversion element 50. The relay optical element 60 superimposes the emitted light from each color zone onto the light incident surface of the image light modulator 40. The image light modulator 40 modulates the temporally colored beams and displays the image.

[0087] like Figure 7 As shown, the color conversion element 50 includes three color zones: red zone R, green zone G, and blue zone B. It is understood that in other embodiments of the present invention, there may be more than three color zones. Each color zone corresponds one-to-one with an electrode unit in the illumination light modulator 10. By controlling the voltage of each electrode unit in the illumination light modulator 10, the emitted light brightness of each pixel area of ​​the illumination light modulator 10 is controlled, thereby controlling the color brightness of the corresponding color zone.

[0088] A single frame of a display image can be divided into multiple subframes. In each subframe, the color of the light emitted from the projection device is one of the three primary colors. Since the display time of a single frame is very short, it can be ignored. Therefore, the image presented to the user is the actual color image after modulation.

[0089] In traditional single-panel projection technology, sequential colored light is typically obtained using a light-emitting element and a color wheel. Whether it's white light with a filter wheel or excitation light with a phosphor wheel, a motor is needed to drive the color wheel to rotate. This color wheel assembly is a mechanical component, which has many problems, such as: mechanical reliability issues; noise caused by the rotation of the color wheel; additional power consumption from the color wheel's control chip; and the fact that mechanical components such as the motor / color wheel do not follow Moore's Law, resulting in excessively high costs that are difficult to reduce through mass production.

[0090] The projection device of this invention uses an illumination light modulator 10 in conjunction with a stationary color light conversion element 50 to achieve the effect of a color wheel. By replacing mechanical light color adjustment with electrical light color adjustment, the color light conversion element 50 of this application is easier to construct compared to a complex and thick color wheel. When combined with the illumination light modulator 10, it can achieve a smaller thickness relative to the color wheel assembly. Simultaneously, it saves the need for a motor and motor control chip required to drive the color wheel, and also saves the electrical energy required to drive the color wheel. Furthermore, the semiconductor structure architecture based on the illumination light modulator 10 allows for mass production through wafer-level manufacturing processes, significantly reducing costs.

[0091] In this embodiment, the illumination modulator 10 is further characterized by the ability to simultaneously control multiple pixel units within a single pixel region using a single electrode unit, with the pixel regions controlled by different electrode units operating independently. Therefore, by independently controlling the first and second electrode units, different color zones of the color conversion element can independently emit light of different colors, or multiple color zones can simultaneously emit mixed light of multiple colors, unlike a color wheel which requires an additional mixing segment to emit mixed-color light. Furthermore, the technical solution of a pixel region containing multiple pixel units, compared to a solution where a pixel region contains only one large pixel unit, decomposes the size, which on the one hand improves overall optical performance (such as uniformity), and on the other hand, disperses and connects the circuitry, preventing the entire pixel region from becoming unusable due to a single circuit failure.

[0092] In a preferred embodiment of this example, the illumination light modulator 10 and the image light modulator 40 are the same type of light modulator. During each image frame, the illumination light modulator 10 and the image light modulator 40 perform illumination light modulation and image modulation respectively based on the same image signal.

[0093] Here, the image illumination modulator 40 and the illumination modulator are the same type of light modulator, meaning that the principle by which the image modulator 40 modulates light is the same as that of the illumination modulator. However, since the illumination modulator 10 is used to modulate the outgoing direction of light to achieve illumination from different directions, while the image modulator 40 is used to modulate light and display images, although the image modulator 40 and the illumination modulator are of the same type, their specific structures still differ. The difference lies in:

[0094] First, the image light modulator 40 modulates light using a single pixel unit as the smallest unit; while the illumination light modulator 10 modulates light using a pixel region containing multiple pixel units as the smallest unit.

[0095] Second, the image light modulator 40 requires a specific pixel driving circuit to drive a pixel unit to emit light and display. The pixel driving circuit includes at least one storage circuit. However, the electrode sub-units under each pixel unit in the same pixel area of ​​the illumination light modulator 10 are connected in series within the same electrode unit range and do not have a storage circuit.

[0096] Specifically, the illumination light modulator 10 can be based on MEMS to modulate light, and the spatial image light modulator 40 can be a digital micromirror device (DMD). The illumination light modulator 10 can include a liquid crystal layer and a transparent electrode layer, and the electrode layer can reflect light. The image light modulator 40 can be a silicon-based liquid crystal. The illumination light modulator 10 can include a liquid crystal layer and a transparent electrode layer, and the electrode layer can transmit light. The image light modulator 40 can be an LCD.

[0097] In this embodiment, the illumination light modulator 40 and the image light modulator 40 are of the same type, and the methods for controlling the image light modulator 40 and the illumination light modulator 10 are also the same. Therefore, the main control circuit can control the illumination light modulator 10 and the image light modulator 40 to work separately through a unified signal, thereby simplifying the operation of the projection device 200.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An illumination light modulator, characterized in that, The illumination light modulator includes multiple pixel regions, each pixel region comprising multiple pixel units, and comprises: A power supply layer, comprising multiple power supply units that are mutually insulated; An electrode layer includes a plurality of electrode units spaced apart, each electrode unit corresponding to a pixel region. Each electrode unit is electrically connected to a power supply unit. The power supply unit is used to input a voltage to the electrode unit corresponding to it. The electrode unit is used to control the direction or polarization state of light incident on the pixel region corresponding to the electrode unit from the illumination light modulator according to the voltage. The state changes of each pixel unit contained in each pixel region are consistent. Each electrode unit includes a plurality of electrode sub-units spaced apart, each electrode sub-unit corresponding to a pixel unit, and the plurality of electrode sub-units of each electrode unit are conductive and connected in series.

2. The illumination light modulator according to claim 1, characterized in that, The illumination light modulator further includes a liquid crystal layer and a transparent electrode layer disposed on the light-emitting side of the electrode layer; the electrode layer is used to reflect light to the liquid crystal layer, and the light is modulated by the liquid crystal layer and emitted from the illumination light modulator.

3. The illumination light modulator according to claim 2, characterized in that, Driven by the electric field formed by the electrode layer and the transparent electrode layer, the liquid crystal in the liquid crystal layer is deflected; The different deflection angles of the liquid crystal result in different polarization states of the light rays refracted by the liquid crystal and emitted from the illumination light modulator.

4. The illumination light modulator according to claim 2 or 3, characterized in that, The illumination light modulator also has a wiring area located around the plurality of pixel areas, the electrode layer is located in the pixel areas, and the power supply layer is located in the wiring area; The electrode layer and the power supply layer are made of the same material and are obtained through the same patterning process.

5. The illumination light modulator according to claim 1, characterized in that, The illumination light modulator adjusts the light based on a microelectromechanical system. The electrode subunit includes a first electrode, a second electrode, and a reset metal pad arranged at intervals. Multiple first electrodes in the same electrode unit are connected in series, and multiple second electrodes in the same electrode unit are connected in series. The power supply unit includes a first power supply unit, a second power supply unit, and a third power supply unit. The first electron supply unit inputs a first voltage to the first electrode, the second electron supply unit inputs a second voltage to the second electrode, and the third electron supply unit inputs a third voltage to the reset metal pad.

6. The illumination light modulator according to claim 5, characterized in that, The reset metal pad changes its tilt direction according to the first voltage, the second voltage, and the third voltage; The tilt direction of the reset metal pad changes, and the light reflected by the reset metal pad changes its emission direction from the illumination light modulator.

7. The illumination light modulator according to claim 2 or 5, characterized in that, The illumination light modulator includes a metal layer, and the electrode layer and the power supply layer are each part of the metal layer.

8. A lighting device, characterized in that, The device includes a light source, a lens, and an illumination light modulator as described in any one of claims 1-7, wherein the illumination light modulator receives and emits light emitted by the light source, and the lens is disposed on the light-emitting side of the illumination light modulator; the lens includes at least a first lens and a second lens, and the plurality of electrode units include at least a first electrode unit and a second electrode unit. The first lens is configured to correspond to the first electrode unit, and the second lens is configured to correspond to the second electrode unit. When the first electrode unit is in an active state, the light emitted from the light source is modulated by the illumination light modulator and then emitted as a first beam from the first lens. When the second electrode unit is in an active state, the light emitted from the light source is modulated by the illumination light modulator and then emitted as a second beam from the second lens. The lighting device can emit either the first beam or the second beam, or both, by independently controlling the first electrode unit and the second electrode unit.

9. A projection device, characterized in that, The light source includes an image light modulator and an illumination light modulator as described in any one of claims 1-7. The illumination light modulator receives light emitted from the light source, modulates the light by illumination light, and then emits light. The light emitted from the illumination light modulator is incident on the image light modulator, modulated by the image light modulator, and then emitted as image light.

10. The projection device according to claim 9, characterized in that, The projection device further includes a color light conversion element and a relay optical element disposed between the illumination light modulator and the image light modulator. The color light conversion element includes multiple color zones, each corresponding to the electrode unit. The relay optical element is used to overlay the emitted light from each color zone onto the light incident surface of the image light modulator. The light emitted from the illumination light modulator is converted into a spatially separated temporal color beam by the color conversion element, and the image light modulator modulates the temporal color beam to display an image.

11. The projection device according to claim 9 or 10, characterized in that, The illumination light modulator and the image light modulator are the same type of light modulator. During each image frame, the illumination light modulator and the image light modulator perform illumination light modulation and image modulation respectively based on the same image signal.

Images