Laser display device

Abstract

The invention provides a laser display device, and relates to the technical field of laser display. The laser display device comprises a light source part, a light transmitting part and a light modulation part, the light source component is configured to emit laser with at least one color, and the laser reaches the light modulation component after passing through the light transmitting component; the light transmitting component is arranged between the light source component and the light modulation component, the light transmitting component is configured to receive incident light in different directions, emergent light comprises first polarized light and second polarized light, and the first polarized light is perpendicular to the second polarized light; the proportions of the first polarized light and the second polarized light of the emergent light corresponding to the incident light in different directions are different; and the light modulation component is configured to modulate the received light beam to obtain the light beam with the to-be-displayed image information. The invention is used for providing a new speckle improvement scheme suitable for the laser display device.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of laser display technology, and more specifically, to a laser display device. Background Art

[0002] Laser-Display Technology (LDT) is an image information terminal display technology that uses lasers as light sources. Compared with traditional LED light sources, laser display has a wider color gamut coverage, better color expression, and more outstanding color reproduction capabilities. Although lasers have advantages such as high color gamut and high color saturation, due to the characteristics of high laser collimation, narrow spectrum, and high coherence, laser speckle is also produced, which seriously affects the quality of laser display images.

[0003] At present, the main methods for eliminating laser speckle include reducing laser temporal coherence, spatial coherence and time averaging. Among them, reducing temporal coherence is mainly achieved by broadening the laser spectrum, including adding lasers of different wavelengths, or increasing the laser spectrum from the laser chip end; reducing spatial coherence is mainly achieved by increasing the optical expansion of the system, including using a diffuser to amplify the laser spot, using a compound eye or optical waveguide to homogenize the laser spot; or changing the laser polarization to orthogonal polarization to eliminate the speckle and reduce the laser coherence. Time averaging mainly involves adding moving parts to the system, such as adding a diffuser wheel, moving diffusers, etc.

[0004] However, the above-mentioned speckle elimination method usually changes the spot size or transmission path of the laser, resulting in the need for additional optical elements to further modulate the light beam, which in turn makes the overall structure of the laser display device more complicated. Therefore, a new solution to improve speckle is needed. Summary of the invention

[0005] An exemplary embodiment of the present application provides a laser display device, which is used to provide a new solution for improving speckles applicable to the laser display device.

[0006] This application provides the following technical solutions:

[0007] The present application provides a laser display device, comprising: a light source component, a light-transmitting component, and a light modulation component;

[0008] The light source component is configured to emit laser light having at least one color, and the laser light reaches the light modulation component after passing through the light-transmitting component;

[0009] The light-transmitting component is disposed between the light source component and the light modulation component, and the light-transmitting component is configured to receive light incident from different directions, and the outgoing light includes a first polarized light and a second polarized light, the first polarized light is perpendicular to the second polarized light, and the ratios of the first polarized light and the second polarized light of the outgoing light corresponding to the light incident from different directions are different;

[0010] The light modulation component is configured to modulate the received light beam to obtain a light beam having image information to be displayed.

[0011] It can be seen from the above technical scheme that in the laser display device provided by the present application, a light-transmitting component is arranged between the light source component and the light modulation component, and the light-transmitting component is configured to receive light incident from different directions, and its output light includes a first polarized light and a second polarized light, the first polarized light is perpendicular to the second polarized light, and the ratios of the first polarized light and the second polarized light of the output light corresponding to the light incident from different directions are different. The light-transmitting component can be used to adjust the polarization distribution of light incident from different directions to be more diversified, thereby improving the speckle problem, and a new scheme for improving speckle suitable for a laser display device is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the implementation methods in the embodiments of the present application or the related technologies, the following is a brief introduction to the drawings required for use in the embodiments or the related technology descriptions. Obviously, the drawings described below are some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0013] Figure 1 A schematic diagram showing the structure of a laser display device in some embodiments is shown;

[0014] Figure 2 A schematic diagram showing the working principle of the light-transmitting component in some embodiments is shown;

[0015] Figure 3 shows a schematic structural diagram of a crystal wave plate in some embodiments;

[0016] Figure 4 A schematic diagram showing the working principle of a crystal wave plate in some embodiments is shown;

[0017] Figure 5 A schematic diagram showing the application principle of crystal wave plates in some embodiments is shown;

[0018] Figure 6 shows a schematic structural diagram of a crystal wave plate in some embodiments;

[0019] Figure 7 A schematic diagram showing the working principle of a crystal wave plate in some embodiments is shown;

[0020] Figure 8 A schematic diagram showing the application principle of crystal wave plates in some embodiments is shown;

[0021] Fig. 9 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0022] Fig.10 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0023] Fig.11 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0024] Fig.12 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0025] Fig.13 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0026] Fig.14 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0027] Fig.15 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0028] Fig.16 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0029] Fig.17 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0030] Fig.18 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0031] Fig.19 A partial structural schematic diagram of a laser display device in some embodiments is shown;

[0032] Fig. 20 A schematic diagram showing the structure of a laser display device in some embodiments is shown;

[0033] Fig.21 A schematic diagram showing the structure of a laser display device in some embodiments is shown;

[0034] Fig. 22 A schematic diagram showing the structure of a laser display device in some embodiments is shown;

[0035] Fig.23 A schematic structural diagram of a laser display device in some embodiments is shown. DETAILED DESCRIPTION

[0036] In order to make the purpose and implementation method of the present application clearer, the exemplary implementation method of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0037] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0038] The terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to all the components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0039] The technical solution provided in the embodiments of the present application can be applied to the field of laser display, for example, in the field of laser projection display. By setting a light source component including lasers of the three primary colors of red, green and blue (RGB), full-color laser display can be achieved; by setting a light-transmitting component for polarization conversion, the polarization distribution of light incident from different directions can be adjusted to be more diversified, thereby improving the speckle problem; at the same time, since the light-transmitting component does not change the direction of the light, it can be located at any position between the light source component and the light modulation component without the need to additionally set up additional optical elements, thereby solving the speckle problem without changing the transmission direction of the light beam (i.e., light), which is beneficial to avoiding the complication of the overall structure of the laser display device.

[0040] The laser display device provided in the embodiment of the present application is exemplarily described below with reference to the accompanying drawings.

[0041] For example, Figure 1 shows a schematic structural diagram of a laser display device 10 in some embodiments, Figure 2 FIG. 1 is a schematic diagram showing the working principle of the light-transmitting component 120 in some embodiments. Figure 1 and Figure 2As shown, the laser display device 10 includes: a light source component 110, a light-transmitting component 120 and a light modulation component 130; the light source component 110 is configured to emit a laser having at least one color, and the laser reaches the light modulation component 130 after passing through the light-transmitting component 120; the light-transmitting component 120 is arranged between the light source component 110 and the light modulation component 130, and the light-transmitting component 120 is configured to receive light incident from different directions (i.e., angles), and the emitted light includes a first polarized light and a second polarized light, the first polarized light is perpendicular to the second polarized light, and the ratios of the first polarized light and the second polarized light of the emitted light corresponding to the light incident from different directions are different; optionally, the light-transmitting component 120 is also configured to keep the incident direction and the emitting direction of the light the same; the light modulation component 130 is configured to modulate the received light beam to obtain a light beam having image information to be displayed.

[0042] The light source component 110 is a component for emitting light, and may include a laser that emits an initial light; the initial light may be a laser having at least one color, and the at least one color may be at least one of basic colors such as red, green, and blue. Correspondingly, the laser may include a monochromatic laser, for example, for realizing a monochromatic display; or may include a multicolor laser, for example, for realizing a full-color display, which is not limited here.

[0043] In the laser display device 10, along the light transmission direction, after the light source component 110, other optical elements for modulating the initial light may be included, such as a beam combining element, a focusing element, a beam expanding element, or other elements known to those skilled in the art, which are not limited here. The laser light emitted by the light source component 110 passes through the optical elements in the laser display device 10 and the light-transmitting component 120 interspersed in the light path, and then reaches the light modulation component 130.

[0044] The light-transmitting component 120 can receive light incident from different directions and perform polarization conversion; and due to different incident angles and different deflection angles, it can form outgoing light with different polarization ratios. For example, Figure 2As shown, the dotted line and the solid line represent light rays incident on the light-transmitting component 120 from different directions and emitted after polarization conversion, wherein the ratio of light rays in two different polarization directions when the light rays represented by the solid line are emitted is a first ratio, and the ratio of light rays in two different polarization directions when the light rays represented by the dotted line are emitted is a second ratio, and the second ratio is different from the first ratio. Thus, the light-transmitting component 120 can adjust the polarization distribution of light incident from different directions to be more diversified by performing polarization conversion on light incident from different directions, thereby improving the speckle problem and providing a new solution for improving speckle. Optionally, since the light-transmitting component 120 does not change the direction of the light, that is, the light emission direction is parallel to the incident direction, it can be located at any position between the light source component 110 and the light modulation component 130 without the need to additionally set up additional optical elements, thereby solving the speckle problem without changing the direction of light beam transmission, which is conducive to avoiding the complication of the overall structure of the laser display device 10.

[0045] The light modulation component 130 can spatially modulate the light beam after the speckle improvement to form a light beam carrying the image information to be displayed; the specific modulation method can be to use the array of lenses to reflect the light at different spatial positions or to use other methods to achieve the spatial modulation of the light beam. Exemplarily, the light modulation component 130 can be a digital micromirror device (DMD) or other spatial light modulation devices, which are not limited here.

[0046] It should be noted that Figure 1 The figure only shows by way of example a light beam in a converging state passing through the light-transmitting component 120; in other embodiments, a light beam in a diverging state may pass through the light-transmitting component 120, and it is only necessary to ensure that light from different directions is incident on the light-transmitting component 120. The embodiment of the present application does not limit whether the light beam incident on the light-transmitting component 120 is a converging light beam or a diverging light beam.

[0047] at the same time, Figure 1 The light source component 110, the light-transmitting component 120 and the light modulation component 130 are only shown as examples, and do not constitute a limitation on the laser display device 10 provided in the embodiment of the present application; in other implementations, other optical elements may be provided between the light source component 110 and the light modulation component 130, before and after the light-transmitting component 120, or after the light modulation component 130, which are not limited here.

[0048] also, Figure 2 Only two light rays with different incident directions are shown by way of example, but this does not constitute a limitation on the light rays incident on the light-transmitting component 120 in the laser display device 10 provided in the embodiment of the present application; in other embodiments, the light rays incident on the light-transmitting component 120 may also include light rays with multiple different directions, which are not limited here.

[0049] The laser display device 10 provided in the embodiment of the present application includes a light source component 110, a light-transmitting component 120 and a light modulation component 130, wherein the laser light having at least one color emitted by the light source component 110 passes through the light-transmitting component 120 and reaches the light modulation component 130, so that the light beam after the speckle improvement is spatially modulated by the light modulation component 130 to obtain a light beam having image information to be displayed, thereby facilitating image display; wherein the light-transmitting component 120 can receive light incident from different directions, emit light with different polarization ratios, and keep the incident direction and the emitting direction of the light beam consistent. At the same time, the light-transmitting component 120 can deflect light incident from different directions at different angles, thereby emitting light with different polarization ratios, thereby achieving a more diversified adjustment of the polarization distribution of light incident from different directions, thereby improving the speckle problem; at the same time, since the light-transmitting component 120 does not change the direction of the light, it can be located at any position between the light source component 110 and the light modulation component 130 without the need to additionally set up additional optical elements, thereby solving the speckle problem without changing the transmission direction of the light beam (i.e., light), which is beneficial to avoiding the complication of the overall structure of the laser display device 10.

[0050] In some embodiments, Figure 3 Schematic diagrams of the structures of crystal wave plates in some embodiments are shown. Figure 1 Based on Figure 3 In the laser display device 10, the light-transmitting component 120 may include a crystal wave plate 121 with uniform thickness; the incident surface 1211 of the crystal wave plate 121 is parallel to the exit surface 1212, and is configured to refract the incident light at the incident surface 1211 and the exit surface 1212 successively to obtain an exit light having the same transmission direction as the incident light.

[0051] Specifically, in the process of passing through the crystal wave plate 121, the light beam first undergoes the first refraction at the incident surface 1211, and then undergoes the second refraction at the exit surface 1212. Since the exit surface 1212 is parallel to the incident surface 1211, the transmission direction of the light beam will not change, that is, the transmission direction of the incident light and the exit light are the same. It can also be understood that the incident angle of the light beam at the incident surface 1211 is the same as its exit angle at the exit surface 1212.

[0052] With such a configuration, since the light emitting direction does not change, the overall viewing angle configuration of the laser display device 10 will not be affected. The crystal wave plate 121 can be disposed at any position between the light source component 110 and the light modulation component 130 .

[0053] For example, Figure 4 Schematic diagram showing the working principle of the crystal wave plate in some embodiments, Figure 5 FIG. 1 is a schematic diagram showing the application principle of the crystal wave plate in some embodiments. Figure 3 Based on Figure 4 and Figure 5 When a parallel laser beam converges after passing through the lens structure, a crystal wave plate with a birefringence effect, such as a half-wave plate, a quarter-wave plate or other types of wave plates, is placed near the convergence point with its optical axis parallel to the surface.

[0054] Polarization refers to the phenomenon that the vibration vector (perpendicular to the propagation direction of the wave) of a transverse wave (light in the embodiment of the present disclosure) is biased in certain directions. Figure 4 Taking the direction shown in FIG. 1 as an example, the arrow from left to right shows the propagation direction of the light; the line segment or ellipse in the propagation direction shows the polarization direction of the light; Figure 5 For example, the direction of the straight line with an arrow is the propagation direction of the light, and the point or line segment in the propagation direction illustrates the polarized light.

[0055] For a crystal wave plate, the polarization direction can be decomposed into a part perpendicular to the optical axis (i.e., o light) and a part parallel to the optical axis (i.e., e light). The o light and the e light have different refractive indices in the crystal wave plate. Therefore, after passing through a wafer wave plate with a thickness of d, the o light and the e light will have a phase difference, as shown below:

[0056]

[0057] Wherein, no represents the refractive index of o light, ne represents the refractive index of e light, δ represents the phase, that is, the polarization direction, and different δ represents different polarization directions. For example, δ=π, which is linearly polarized light;

[0058] When δ=nπ+0.5π, it is elliptically polarized light.

[0059] For example, Figure 4 As shown in the figure, when the light beam enters the crystal wave plate along the normal direction (i.e., the direction perpendicular to the surface of the crystal wave plate 121), the polarization direction can be decomposed into two mutually perpendicular components, namely o light and e light; wherein the e light polarization is parallel to the plane formed by the optical axis and the incident light, and the o light is perpendicular to this plane. Specifically, the light beam is shown by vector A in the figure, and P represents its polarization direction; Ae shows e light, and Ao shows o light.

[0060] Exemplarily, taking the crystal wave plate 121 as a 1 / 2 wave plate (ie, a half-wave plate), if the polarization direction of the incident light forms an angle of 45° with the optical axis of the half-wave plate, the polarization direction of the outgoing light rotates 90°.

[0061] like Figure 2 or Figure 5As shown in FIG. 1 , when a light beam is incident on the surface of a crystal wave plate, the outgoing light is divided into o-light and e-light and is emitted at different positions of the crystal wave plate. The ratio of the o-light and e-light components is related to the incident angle and the polarization direction of the incident light. Specifically, when the incident angle is different, the ratio of the o-light and e-light components is different (e.g. Figure 2 ); When the polarization direction of the incident light is different, the ratio of the o-light and e-light components is also different; and the polarization direction P of the light beam formed by different ratios of o-light and e-light is also different (such as Figure 4 ). Further, when the crystal wave plate emits o light and e light, these two beams of light are linearly polarized lights that are perpendicular to each other (such as Figure 5 ). In which, no matter whether the incident light is perpendicular to the surface of the crystal wave plate or not, the outgoing light will be divided into o-light and e-light, but when the incident light is perpendicular, the ratio of o-light and e-light in each direction is the same, so there is only one synthesized polarization direction, and polarization diversification adjustment cannot be achieved; in the embodiment of the present disclosure, by using light from different directions to be incident on the crystal wave plate, polarization diversification adjustment can be achieved, thereby improving speckle.

[0062] In the embodiment of the present application, when light incident from different directions, that is, light at different angles, is incident on different positions of the crystal wave plate, the ratio of o-light to e-light is different due to the different angles between the incident light and the optical axis of the crystal wave plate. Therefore, for incident light at different angles and / or different positions, the polarization of the emitted light is different, and the ratio of o-light to e-light is different. In this way, the polarization directions emitted from different positions can be divided into two types: o-light and e-light, and the ratio of o-light to e-light at different positions is different, the coherence will be reduced, and thus the speckle reduction will be caused.

[0063] In the above implementation, after the same beam of light passes through the crystal wave plate with birefringence effect, two beams of light with different polarization directions will be generated; among them, for the incident light, whether it is elliptically polarized light or linearly polarized light, it is necessary to pay attention to the angle between the polarization direction of the incident light and the optical axis of the crystal wave plate. If it is not incident parallel to or perpendicular to the optical axis, it can be divided into non-zero o light and e light components; if it is incident perpendicular to the optical axis, it will also be divided into two components, but one of the components is 0, so the polarization direction of the outgoing light will be the same as or perpendicular to the polarization direction of the incident light.

[0064] Exemplarily, in the above embodiment, if the incident light (for example, red light) is P light, the vertically incident half-wave plate will become S light, that is, the phase difference between the outgoing light and the incident light is π; if the polarization direction of the incident light is at a certain angle to the optical axis (that is, it is not parallel or perpendicular to the optical axis), it can be divided into o light and e light components.

[0065] The laser display device 10 proposed in the embodiment of the present application is a laser display device that improves speckle based on a crystal wave plate 121. The crystal wave plate 121 is located at a position in the optical path where the light beam has different angles, and can make the polarization variables of light incident at different angles different, thereby adjusting the polarization distribution of light incident from different directions to be more diversified, thereby achieving the effect of improving speckle (i.e., reducing the influence of speckle); at the same time, since the exit surface 1212 of the crystal wave plate 121 is parallel to the incident surface 1211, that is, the crystal wave plate 121 is a flat plate and does not affect the transmission direction of the light beam, it can be placed at any position in the optical path without the need to additionally set up additional optical elements, thereby not increasing the overall complexity of the laser display device 10.

[0066] In some embodiments, in the laser display device 10 , the crystal wave plate 121 is a half-wave plate and / or a quarter-wave plate.

[0067] With such an arrangement, the polarization directions of light incident from different directions can be adjusted differently, thereby making the polarization distribution of the outgoing light more diversified and improving speckle.

[0068] In other embodiments, the crystal wave plate 121 may also be other optical elements having birefringence characteristics, which is not limited here.

[0069] In some embodiments, Figure 6 Schematic diagrams showing the structures of crystal wave plates in some embodiments are shown. Figure 7 Schematic diagram showing the working principle of the crystal wave plate in some embodiments, Figure 8 FIG. 2 shows a schematic diagram of the application principle of the crystal wave plate in some embodiments. Figure 6-Figure 8 As shown in any of the figures, the emission surface 1212 of the crystal wave plate 121 is configured as a diffusion surface 1213; the diffusion surface 1213 includes an irregular concave-convex structure.

[0070] Exemplarily, the incident surface 1211 of the crystal wave plate 121 can be a smooth surface, and the exit surface 1212 can be made into an irregular diffusion surface 1213 by etching or other methods. The diffusion surface 1213 can also be called a diffusion layer; the crystal wave plate 121 can be placed at any position between the light source component 110 and the light modulation component 130.

[0071] like Figure 6-Figure 8 As shown, no matter the light beam is incident on the crystal wave plate 121 at different angles or at different positions at the same angle, the polarization of the outgoing light will be different due to the birefringence characteristics of the crystal wave plate 121 and the characteristics of the surface diffusion layer. That is, no matter the angle or position at which the light beam is incident on the crystal wave plate 121 is different, the polarization after passing through the crystal wave plate 121 will be different, thereby reducing the laser coherence and reducing the laser speckle. Figure 8In the figure, d1 and d2 represent the optical path lengths at different positions.

[0072] Exemplarily, the surface of the crystal wave plate 121 can be micro-machined to make it into an irregular surface like a diffuser surface. The light passing through the crystal wave plate 121 will produce different polarization elimination effects due to the different paths it passes through.

[0073] In some embodiments, Fig. 9 shows a partial structural schematic diagram of a laser display device in some embodiments, Fig.10 FIG. 1 is a schematic diagram showing a partial structure of a laser display device in some embodiments. Figure 1 and Figure 3 Based on Fig. 9 or Fig.10 The laser display device 10 also includes: a lens structure 140, the lens structure 140 includes a focusing lens 141 and / or a beam expanding lens 142; the focusing lens 141 is configured to form a converging light beam, and the beam expanding lens 142 is configured to form a diverging light beam; wherein the crystal wave plate 121 is arranged behind the lens structure 140 along the light transmission direction.

[0074] like Fig. 9 As shown, the lens structure 140 is a focusing lens 141, which can converge the light beam. The crystal wave plate 121 is placed behind the focusing lens 141 along the light transmission direction, and can adjust the polarization of the converged light beam, thereby adjusting the polarization of light incident from different directions in the converged light beam, so that the polarization ratio of the emergent light is different, polarization diversification is achieved, and speckle is improved; at the same time, since the crystal wave plate 121 is set at the place where the light beam converges, the area of ​​the crystal wave plate 121 can be made small, which is conducive to saving space.

[0075] like Fig.10 As shown, the lens structure 140 is a beam expander lens 142, which can diverge the light beam. The crystal wave plate 121 is placed behind the beam expander lens 142 along the light transmission direction, and can adjust the polarization of the divergent light beam, thereby adjusting the polarization of light incident from different directions in the divergent light beam, so that the polarization ratio of the outgoing light is different, achieving polarization diversification and improving speckle; at the same time, since the crystal wave plate 121 is set at the divergence of the light beam, the spot size at this position is larger, and the setting flexibility of the crystal wave plate 121 is higher.

[0076] In other embodiments, the lens structure 140 in the laser display device 10 may include a focusing lens 141 and a beam expanding lens 142 at the same time, and the crystal wave plate 121 may be arranged in front of or behind at least one lens structure 140 to meet the requirement that light rays from different directions are incident on the crystal wave plate 121, which is not limited here.

[0077] In some embodiments, Fig.11 shows a partial structural schematic diagram of a laser display device in some embodiments, Fig.12 shows a partial structural schematic diagram of a laser display device in some embodiments, Fig.13 FIG. 1 is a schematic diagram showing a partial structure of a laser display device in some embodiments. Figure 1 and Figure 3 On the basis of Figure 11-13 As shown in any figure, the laser display device 10 further includes: a light pipe 150; the light pipe 150 is configured to receive a convergent light beam and emit a light beam with uniform brightness; wherein the crystal wave plate 121 is arranged in front of the light pipe 150 along the light transmission direction.

[0078] For example, the crystal wave plate 121 may be placed at the entrance of the light pipe 150, such as Fig.11 or Fig.12 As shown, since the light beam at the entrance of the light pipe 150 is in a focused state, light at different angles will be incident on the crystal wave plate 121, and the polarization ratios of the corresponding outgoing light are different, and the polarization directions are diversified, thereby improving the speckle problem.

[0079] For example, Fig.11 or Fig.12 As shown, regardless of whether the crystal wave plate 121 includes the diffusion surface 1213, the crystal wave plate 121 can be located between the lens structure 140 and the light pipe 150; or Fig.13 As shown, in the structure where the crystal wave plate 121 includes a diffusion surface 1213, the crystal wave plate 121 can also be arranged before the lens structure 140. In this structure, the diffusion surface 1213 of the crystal wave plate 121 is first used to perform polarization differentiation adjustment on the light beam, and then the lens structure 140 is used to focus the light beam, and the light pipe 150 is used to homogenize the light beam.

[0080] In some embodiments, Fig.14 shows a partial structural schematic diagram of a laser display device in some embodiments, Fig.15 FIG. 1 is a schematic diagram showing a partial structure of a laser display device in some embodiments. Figure 1 and Figure 3 On the basis of Fig.14 or Fig.15 As shown, the laser display device 10 may also include: a lens structure 140, configured to converge a light beam; a first telescope 161 and a second telescope 162, arranged between the light source component 110 and the lens structure 140; the first telescope 161 is configured to converge a light beam, and the second telescope 162 is configured to diverge a light beam; wherein the crystal wave plate 121 is located between the first telescope 161 and the second telescope 162 along the light transmission direction, and / or is located behind the lens structure 140.

[0081] The first telescope 161 and the second telescope 162 can compress the light spot to obtain a light spot with a higher energy density. The light spot is further processed by the lens structure 140, that is, it can be homogenized after being converged.

[0082] For example, Fig.14 As shown, the crystal wave plate 121 can be located at the focal position of the first telescope 161, and the focal position of the first telescope 161 and the focal position of the second telescope 162 can be the same position; or, the crystal wave plate 121 can be located at any position between the first telescope 161 and the second telescope 162, and both can satisfy the light from different directions incident on the crystal wave plate 121, thereby facilitating the realization of polarization diversification adjustment and improving speckle.

[0083] For example, Fig.15 As shown, the number of crystal wave plates 121 can be two, wherein one crystal wave plate 121 is located between the first telescope 161 and the second telescope 162, and the other crystal wave plate 121 is located after the lens structure 140, both of which can satisfy the requirement that light rays from different directions are incident on the crystal wave plate 121, thereby facilitating polarization diversification adjustment and improving speckle.

[0084] In other embodiments, when the number of the crystal wave plate 121 is one, the crystal wave plate 121 may also be located only behind the lens structure 140 ( Fig.14 and Fig.15 (not shown), it is sufficient to satisfy the requirement that light rays from different directions are incident on the crystal wave plate 121, and this is not limited here.

[0085] In the embodiment of the present application, the crystal wave plate 121 may be a structure in which both the incident surface and the exit surface are smooth planes, or a structure in which the exit surface is a diffusion surface, which is not limited here.

[0086] In other implementations, a diffuser may also be placed at the location of the crystal wave plate 121 to improve speckle, which is not limited here.

[0087] In some embodiments, Fig.16 shows a partial structural schematic diagram of a laser display device in some embodiments, Fig.17 FIG. 1 is a schematic diagram showing a partial structure of a laser display device in some embodiments. Fig.14 or Fig.15 On the basis of Fig.16 or Fig.17 As shown, the laser display device 10 may further include: a light pipe 150 , and a lens structure 140 is disposed between the second telescope 162 and the light pipe 150 .

[0088] Specifically, the second telescope 162 and the first telescope 161 form a group of telescopes to compress the light spot; the lens structure 140 can converge the compressed light spot here, and the light pipe 150 receives the converged light spot and performs homogenization processing to improve the uniformity of energy distribution while improving the energy density of the light spot.

[0089] For example, Fig.16 As shown, along the light beam transmission direction, the first telescope 161, the crystal wave plate 121, the second telescope 162, the lens structure 140 and the light guide 150 are arranged in sequence; or, as Fig.17 As shown, along the light beam transmission direction, the first telescope 161, the crystal wave plate 121 (one), the second telescope 162, the lens structure 140, the crystal wave plate 121 (the second) and the light guide 150 are arranged in sequence.

[0090] In other embodiments, the number and arrangement order of the optical elements may be set in other ways, which are not limited here.

[0091] In some embodiments, Fig.18 shows a partial structural schematic diagram of a laser display device in some embodiments, Fig.19 FIG. 1 is a schematic diagram showing a partial structure of a laser display device in some embodiments. Fig.14 or Fig.15 On the basis of Fig.18 or Fig.19 As shown, the laser display device 10 may further include: a fly-eye lens 170 , which is disposed between the second telescope 162 and the lens structure 140 .

[0092] Specifically, the second telescope 162 and the first telescope 161 form a group of telescopes to compress the light spot; the reduced light spot can illuminate the compound eye lens 170, which is first used to even the light, and then the lens structure 140 is used to converge the light.

[0093] For example, Fig.18 As shown, along the light beam transmission direction, the first telescope 161, the crystal wave plate 121, the second telescope 162, the fly-eye lens 170 and the lens structure 140 are arranged in sequence; or, as Fig.19 As shown, along the light beam transmission direction, the first telescope 161, the crystal wave plate 121 (one), the second telescope 162, the fly-eye lens 170, the lens structure 140 and the crystal wave plate 121 (the second) are arranged in sequence.

[0094] In other embodiments, the number and arrangement order of the optical elements may be set in other ways, which are not limited here.

[0095] In the laser display device 10 provided in the above embodiment, since the light-transmitting component 120 does not change the transmission direction of the light beam, it can be set at any position between the light source component 110 and the light modulation component 130, so it can meet the application requirements of small-size design. Exemplarily, the light source component 110 may include a semiconductor laser chip. Since the number and packaging method of the semiconductor laser chips in the light source component 110 are positively correlated with the final output luminous flux, for small-size laser TVs or laser micro-projectors, the laser chips used are getting smaller and smaller, and the light spots and optical extensions are also getting smaller and smaller. By matching the size of the light-transmitting component 120 with it, it is helpful to reduce the difficulty of laser homogenization and laser speckle elimination.

[0096] In some embodiments, Fig. 20 FIG. 1 shows a schematic diagram of the structure of a laser display device in some embodiments. Figure 1 and Figure 3 On the basis of Fig. 20 As shown, in the laser display device 10 , the light-transmitting component 120 further includes a diffuser 122 and a diffuser wheel 123 ; the diffuser 122 and the diffuser wheel 123 have the same optical axis, and the diffuser wheel 123 is configured to rotate around the optical axis relative to the diffuser 122 .

[0097] The diffusion wheel 123 can also be called a vibration diffuser. Since the laser emitted by the light source component 110 has high coherence and its intensity distribution is Gaussian, the uniformity is poor; in the embodiment of the present application, the light-transmitting component 120 also includes a diffusion sheet 122 and a diffusion wheel 123, which can increase the uniformity of the laser, reduce the coherence of the laser, and reduce the speckle.

[0098] In an embodiment of the present application, the light-transmitting component 120 may include a crystal wave plate 121, a diffuser 122 and a diffuser wheel 123, wherein the diffuser 122, the crystal wave plate 121 and the diffuser wheel 123 may be arranged in sequence along the light beam transmission direction; the lens structure 140 may be arranged between the diffuser 122 and the crystal wave plate 121, and the light guide 150 may be arranged behind the diffuser wheel 123.

[0099] In other embodiments, the number and arrangement order of the optical elements may be set in other ways, which are not limited here.

[0100] In some embodiments, Fig.21 shows a schematic structural diagram of a laser display device in some embodiments, Fig. 22 shows a schematic structural diagram of a laser display device in some embodiments, Fig.23 FIG. 2 shows a schematic diagram of the structure of a laser display device in some embodiments. Figure 21-23 As shown in any of the figures, in the laser display device 10, the light source component 110 includes a laser with a preset light output color.

[0101] Exemplarily, the light source component 110 may include a green laser 111, a blue laser 112, and a red laser 113. Correspondingly, the preset light emission colors may include green, blue, and red, so as to achieve full-color display.

[0102] In other embodiments, the light source component 110 may also include a monochromatic laser, a dual-color laser, or lasers of other colors, which are not limited herein.

[0103] For example, continue to refer to Figure 21-23 As shown in any of the figures, in the laser display device 10, the light-transmitting component 120 further includes: a polarization modulation element 124, which is arranged on the light-emitting side of at least part of the laser; the polarization modulation element 124 is configured to modulate the laser light of a single polarization direction into a laser light having at least two polarization directions for laser light of at least one color.

[0104] Exemplarily, the polarization modulation element 124 can be disposed between the laser and the crystal wave plate 121, and can perform polarization modulation on the three-color laser light before beam combination, or on the multi-color laser light after beam combination, which is not limited here. Among them, by providing the polarization modulation element 124, the laser light polarized in a single direction can be modulated into laser light with different polarization directions, so that at least one of the direction, incident position and polarization direction of the light beam incident to the crystal wave plate 121 can be different, thereby increasing the randomness of the polarization of the laser light after passing through the crystal wave plate 121, that is, increasing the difference, improving the uniformity, and improving the speckle.

[0105] For example, Fig.21 As shown, the polarization modulation element 124 can be set corresponding to the red laser 113, and is used to change the polarization direction of the red laser emitted by part of the red laser 113, so that the red laser can include P light and S light when incident on the crystal wave plate 121, thereby further improving the polarization uniformity and improving the speckle.

[0106] For example, Fig. 22 As shown, the polarization modulation element 124 can be set corresponding to the green laser 111, the blue laser 112 and the red laser 113; wherein, the polarization modulation element 124 may include a modulation area and a hollow area. For each color of light, part of the light changes its deflection direction through the modulation area, and part of the light keeps its polarization direction unchanged through the hollow area. Therefore, each color of light includes two different polarization directions when incident on the crystal wave plate 121, which further increases the randomness of the laser polarization after passing through the crystal wave plate 121, that is, increases the difference, improves the uniformity, and improves the speckle.

[0107] Above Fig.21 and Fig. 22In the embodiment, the polarization modulation element 124 corresponds to a monochromatic laser setting. In other embodiments, the polarization modulation element 124 may also correspond to a multi-color laser setting, and may perform polarization modulation on the combined light beams, such as Fig.23 shown.

[0108] In the above implementation mode, if Figure 20-23 As shown in any figure, the structure of a three-color laser display device is shown. Among them, the red, green and blue lasers are combined by a dichroic plate, and then after passing through a diffuser 122, a lens structure 140, a crystal wave plate 121 and a diffuser wheel 123, they are incident on a light guide 150. The lasers are reflected back and forth in the light guide 150, and finally output a uniform white light spot; behind the light guide 150 is a set of lighting system 102, which is usually composed of 2 to 4 lenses, and is used to illuminate the uniform white light output by the light guide 150 to the light modulation component 130, such as a DMD display chip, and then the image formed by the light modulation component 130 is magnified by the TIR lens 104 and the lens 160 to project an enlarged image.

[0109] The polarization modulation element 124 may be located between the laser and the dichroic plate, or at any position between the crystal wave plate 121 and the laser, which is not limited here.

[0110] The crystal wave plate 121 may adjust the entire light beam or a portion of the light beam, which is not limited here.

[0111] In the laser display device 10 provided in the embodiment of the present application, by arranging the light source component 110 to include red, green and blue three-color lasers, full-color laser display can be achieved; by arranging the light-transmitting component 120 to include a crystal wave plate 121, polarization conversion of different polarization ratios can be achieved for light incident from different directions without changing the transmission direction of the light beam, thereby improving polarization diversity and improving speckle while facilitating miniaturization design; optionally, the exit surface 1212 of the crystal wave plate 121 may be a diffusion surface 1213, thereby further improving speckle; optionally, the light-transmitting component 120 may also include a diffusion plate or a diffusion wheel, thereby improving the uniformity of the light spot and further improving the speckle; optionally, the light-transmitting component 120 may also include a polarization modulation element 124, which is used to increase the polarization diversity before the crystal wave plate 121 and further improve the speckle (i.e., speckle contrast).

[0112] In other embodiments, the laser display device 10 may further include a projection screen or other components, which are not described or limited herein.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0114] For the convenience of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. A laser display device, characterized in that: include: A light source component, a light transmitting component and a light modulating component; The light source component is configured to emit laser light having at least one color, and the laser light reaches the light modulation component after passing through the light-transmitting component; The light-transmitting component is disposed between the light source component and the light modulation component, and the light-transmitting component is configured to receive light incident from different directions, and the outgoing light includes a first polarized light and a second polarized light, the first polarized light is perpendicular to the second polarized light, and the ratios of the first polarized light and the second polarized light of the outgoing light corresponding to the light incident from different directions are different; The light modulation component is configured to modulate the received light beam to obtain a light beam having image information to be displayed.

2. The laser display device according to claim 1, characterized in that: The light-transmitting component is also configured to keep the incident direction and the emitting direction of the light the same.

3. The laser display device according to claim 2, characterized in that: The light-transmitting component comprises a crystal wave plate with uniform thickness; The incident surface and the exit surface of the crystal wave plate are parallel, and are configured to refract the incident light at the incident surface and then at the exit surface to obtain an exit light whose transmission direction is the same as that of the incident light.

4. The laser display device according to claim 3, characterized in that: The crystal wave plate is a half-wave plate and / or a quarter-wave plate.

5. The laser display device according to claim 3, characterized in that: The exit surface of the crystal wave plate is set as a diffusion surface; The diffusion surface includes an irregular concave-convex structure.

6. The laser display device according to claim 3, characterized in that: Also includes: A lens structure, wherein the lens structure comprises a focusing lens and / or a beam expanding lens; The focusing lens is configured to form a converging light beam, and the beam expanding lens is configured to form a diverging light beam; Wherein, the crystal wave plate is arranged behind the lens structure along the light transmission direction.

7. The laser display device according to claim 3, characterized in that: Also includes: Light guide; The light guide is configured to receive a convergent light beam and emit a light beam with uniform brightness; Wherein, the crystal wave plate is arranged before the light guide along the light transmission direction.

8. The laser display device according to claim 3, characterized in that: Also includes: a lens structure configured to converge a light beam; A first telescope and a second telescope are arranged between the light source component and the lens structure; the first telescope is configured to converge the light beam, and the second telescope is configured to diverge the light beam; Wherein, the crystal wave plate is located between the first telescope and the second telescope along the light transmission direction, and / or is located behind the lens structure.

9. The laser display device according to claim 8, characterized in that: Also includes: a light guide tube, wherein the lens structure is disposed between the second telescope and the light guide tube; Or a fly-eye lens, wherein the fly-eye lens is arranged between the second telescope and the lens structure.

10. The laser display device according to any one of claims 2 to 8, characterized in that: The light-transmitting component further includes a diffusion sheet and a diffusion wheel; The diffuser sheet and the diffuser wheel have the same optical axis, and the diffuser wheel is configured to rotate around the optical axis relative to the diffuser sheet; And / or, the light source component includes a laser having a preset light emission color; The light-transmitting component further comprises: a polarization modulation element, which is arranged on the light-emitting side of at least part of the laser; The polarization modulation element is configured to modulate laser light with a single polarization direction into laser light with at least two polarization directions for laser light of at least one color.

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