Light source device and display device
By reversing the arrangement of light sources with different wavelengths, the light source device achieves uniform illuminance distribution and suppresses speckle generation, addressing the issue of non-uniformity in laser-based devices without increasing size or cost.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- NICHIA CORP
- Filing Date
- 2022-05-13
- Publication Date
- 2026-05-21
AI Technical Summary
Speckle generation occurs in light source devices using laser light sources due to non-uniform illuminance distribution and wavelength bias, which is exacerbated by the difficulty in averaging angular multiplicity for each wavelength, leading to increased speckle contrast values.
The arrangement of light sources with different wavelengths is reversed in vertical, horizontal, and vertical directions, ensuring that light of varying wavelengths is incident on a wavelength multiplexing member to achieve a sparse wavelength distribution, thereby averaging the angle multiplicity and reducing speckle generation without the need for additional components like a subfly array lens.
This configuration results in a uniform illuminance distribution, effectively suppressing speckle generation while maintaining a compact device size and cost-effectiveness by eliminating the need for additional optical elements.
Smart Images
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Abstract
Description
Technical Field
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[0001] The present invention relates to a light source device and a display device.
Background Art
[0002] A light source device is used in a display device such as a projector. In the light source device, it is desired to equalize the illuminance distribution. [[ID=According to an embodiment of the present invention, the light source device includes a first optical member, a second optical member, and a light source unit. The light source unit includes a first light source that emits a first laser beam having a first peak wavelength, a second light source that emits a second laser beam having a second peak wavelength different from the first peak wavelength, a third light source that emits a third laser beam having a third peak wavelength different from the first peak wavelength and also different from the second peak wavelength, a fourth light source that emits a fourth laser beam having the second peak wavelength, a fifth light source that emits a fifth laser beam having the third peak wavelength, a sixth light source that emits a sixth laser beam having the second peak wavelength, a seventh light source that emits a seventh laser beam having the first peak wavelength, and an eighth light source that emits an eighth laser beam having the second peak wavelength. The first laser beam passes through the first optical member. The second laser beam passes through the second optical member. The third laser beam is reflected by the second optical member. The fourth laser beam is reflected by the first optical member. The fifth laser beam passes through the first optical element. The sixth laser beam passes through the second optical element. The seventh laser beam is reflected by the second optical element. The eighth laser beam is reflected by the first optical element. [Effects of the Invention]
[0006] According to embodiments of the present invention, a light source device and a display device capable of suppressing the occurrence of speckles are provided. [Brief explanation of the drawing]
[0007] [Figure 1] Figure 1 is a schematic perspective view illustrating a light source device according to the first embodiment. [Figure 2] Figure 2 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 3] Figure 3 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 4] Figure 4 is a schematic diagram illustrating the state of light according to the first embodiment. [Figure 5] Figure 5 is a schematic diagram illustrating the state of light according to the first embodiment. [Figure 6] Figure 6 is a schematic diagram illustrating the state of light according to the first embodiment. [Figure 7] Figure 7 is a schematic diagram illustrating the state of light according to the first embodiment. [Figure 8] Figure 8 is a schematic perspective view illustrating a light source device according to the first embodiment. [Figure 9] Figure 9 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 10] Figure 10 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 11] Figure 11 is a schematic perspective view illustrating a light source device according to the first embodiment. [Figure 12] Figure 12 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 13] Figure 13 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 14] Figure 14 is a schematic perspective view illustrating a light source device according to the first embodiment. [Figure 15] Figure 15 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 16] Figure 16 is a schematic plan view illustrating a light source device and display device according to the first embodiment. [Figure 17] Figure 17 is a schematic plan view illustrating a light source device and display device according to the second embodiment. [Modes for carrying out the invention]
[0008] Embodiments of the present invention will be described below with reference to the drawings. Please note that the drawings are schematic or conceptual, and the relationships between the thickness and width of each part, as well as the ratios of the sizes of the parts, may not necessarily be identical to those of reality. Even when representing the same part, the dimensions and ratios may be depicted differently in different drawings. In the specification of the present application, elements similar to those described above with respect to the previously presented figures are denoted by the same reference numerals, and detailed descriptions thereof are omitted as appropriate.
[0009] (First Embodiment) FIG. 1 is a schematic perspective view illustrating a light source device 110 according to the first embodiment. FIGS. 2 and 3 are schematic plan views illustrating the light source device 110 and the display device 210 according to the first embodiment. As shown in FIGS. 1 to 3, the light source device 110 according to the embodiment includes a first optical member 21, a second optical member 22, and a light source unit 10. The light source unit 10 includes a first light source 11, a second light source 12, a third light source 13, a fourth light source 14, a fifth light source , a sixth light source 16, a seventh light source 17, and an eighth light source 18.
[0010] As shown in FIG. 2, the first light source 11 emits a first laser beam 11L having a first peak wavelength. The second light source 12 emits a second laser beam 12L having a second peak wavelength. The second peak wavelength is different from the first peak wavelength. The third light source 13 emits a third laser beam 13L having a third peak wavelength. The third peak wavelength is different from the first peak wavelength and also different from the second peak wavelength. The fourth light source 14 emits a fourth laser beam 14L having the second peak wavelength.
[0011] As shown in FIG. 3, the fifth light source 15 emits a fifth laser beam 15L having the third peak wavelength. The sixth light source 16 emits a sixth laser beam 16L having the second peak wavelength. The seventh light source 17 emits a seventh laser beam 17L having the first peak wavelength. The eighth light source 18 emits an eighth laser beam 18L having the second peak wavelength.
[0012] As shown in FIG. 2, the first laser beam 11L passes through the first optical member 21. The second laser beam 12L passes through the second optical member 22. The third laser beam 13L is reflected by the second optical member 22. The fourth laser beam 14L is reflected by the first optical member 21.
[0013] As shown in Figure 3, the fifth laser beam 15L passes through the first optical member 21. The sixth laser beam 16L passes through the second optical member 22. The seventh laser beam 17L is reflected by the second optical member 22. The eighth laser beam 18L is reflected by the first optical member 21.
[0014] The first optical element 21 and the second optical element 22 are, for example, dichroic mirrors.
[0015] As shown in Figure 1, for example, the first light source 11, the second light source 12, the fifth light source 15, and the sixth light source 16 are included in the first module 10A. The third light source 13, the fourth light source 14, the seventh light source 17, and the eighth light source 18 are included in the second module 10B.
[0016] In these two modules, the arrangement of light sources with different wavelengths is reversed in the vertical, horizontal, and vertical directions. This configuration makes it easier to obtain light with a uniform illuminance distribution. According to the embodiment, a light source device is provided that can suppress the generation of speckle.
[0017] Speckle can occur in light source devices that use laser light sources. For example, in the light source device shown in Figures 1 to 3, when light sources of different wavelengths are provided in the same orientation in the up, down, left, and right directions, and light rays are incident on a wavelength multiplexing member from each light source, light of the same wavelength is incident near the same wavelength multiplexing member, resulting in wavelength-biased light being emitted from the wavelength multiplexing member. As a result, wavelength bias occurs within the irradiation area of the light emitted from the wavelength multiplexing member. The illuminance distribution tends to be non-uniform, and wavelength unevenness tends to be large. Therefore, in the member into which the light emitted from the light source device is incident, the incident angle differs depending on the wavelength, and the angular multiplicity for each wavelength is difficult to average out. When the angular multiplicity for each wavelength is difficult to average out, the speckle contrast value increases, and speckle occurs.
[0018] To suppress the difference in incident angle due to wavelength and thus reduce speckle generation, a configuration can be considered in which a subfly array lens is added between the wavelength multiplexing member and the display device. By adding a subfly array lens, the illuminance distribution of the light emitted from the wavelength multiplexing member is made uniform. By making the illuminance distribution uniform, the angular multiplicity for each wavelength of light incident on the optical switch is averaged out, and the generation of speckle can be suppressed. However, adding a subfly array lens increases the number of parts and lengthens the optical distance. As a result, the optical device becomes larger. In addition, adding a subfly array lens increases the cost.
[0019] In contrast, in the light source device 110 according to this embodiment, the arrangement of light sources with different wavelengths is reversed in the vertical, horizontal, and vertical directions, and light rays are incident from each light source onto the wavelength multiplexing member (first optical member 21 or second optical member 22). By reversing the arrangement of each light source, light of different wavelengths is incident near the same wavelength multiplexing member, so that light with a sparse wavelength distribution is emitted from the wavelength multiplexing member. As a result, the wavelength distribution within the irradiation area of the light emitted from the wavelength multiplexing member becomes sparse, and the illuminance distribution is more easily made uniform. By making the illuminance distribution uniform, the difference in incident angle due to wavelength is suppressed in the member into which the light emitted from the light source device is incident, and the angle multiplicity for each wavelength is averaged. By averaging the angle multiplicity for each wavelength, the speckle contrast value can be reduced, and the occurrence of speckle can be suppressed. For example, the illuminance distribution can be made uniform and the angle multiplicity for each wavelength can be averaged without adding a subfly array lens. By eliminating the need for a subfly array lens, it is possible to provide a light source device that suppresses speckle generation while keeping the device size and cost down.
[0020] In one example, the second peak wavelength is longer than the first peak wavelength. The first peak wavelength is longer than the third peak wavelength.
[0021] For example, the first laser beam 11L is green light. The peak wavelength of the green light is between 495nm and 570nm. The second laser beam 12L is red light. The peak wavelength of the red light is between 605nm and 750nm. The third laser beam 13L is blue light. The peak wavelength of the blue light is between 420nm and 494nm. The fourth laser beam 14L is red light. The fifth laser beam 15L is blue light. The sixth laser beam 16L is red light. The seventh laser beam 17L is green light. The eighth laser beam 18L is red light.
[0022] As shown in Figures 1 to 3, the direction from the first light source 11 to the second light source 12 follows the first direction D1. The direction from the third light source 13 to the fourth light source 14 follows the second direction D2. The second direction D2 intersects with the first direction D1. The direction from the fifth light source 15 to the sixth light source 16 follows the first direction D1. The direction from the seventh light source 17 to the eighth light source 18 follows the second direction D2.
[0023] The direction from the fifth light source 15 to the first light source 11 is along the third direction D3. The third direction D3 intersects the plane containing the first direction D1 and the second direction D2. The direction from the sixth light source 16 to the second light source 12 is along the third direction D3. The direction from the seventh light source 17 to the third light source 13 is along the third direction D3. The direction from the eighth light source 18 to the fourth light source 14 is along the third direction D3.
[0024] For example, let the first direction D1 be the X-axis direction. Let the direction perpendicular to the X-axis direction be the Y-axis direction. Let the direction perpendicular to both the X-axis and Y-axis directions be the Z-axis direction. The second direction D2 is, for example, the Y-axis direction. The third direction D3 is, for example, the Z-axis direction.
[0025] As shown in Figure 2, the first laser beam 11L is emitted from the first light source 11 along the second direction D2. The second laser beam 12L is emitted from the second light source 12 along the second direction D2. The third laser beam 13L is emitted from the third light source 13 along the first direction D1. The fourth laser beam 14L is emitted from the fourth light source 14 along the first direction D1.
[0026] As shown in Figure 3, the fifth laser beam 15L is emitted from the fifth light source 15 along the second direction D2. The sixth laser beam 16L is emitted from the sixth light source 16 along the second direction D2. The seventh laser beam 17L is emitted from the seventh light source 17 along the first direction D1. The eighth laser beam 18L is emitted from the eighth light source 18 along the first direction D1.
[0027] In this example, the distance between the first light source 11 and the third light source 13 is shorter than the distance between the first light source 11 and the fourth light source 14. The distance between the first light source 11 and the third light source 13 is shorter than the distance between the second light source 12 and the third light source 13. The distance between the fifth light source 15 and the seventh light source 17 is shorter than the distance between the sixth light source 16 and the seventh light source 17. The distance between the fifth light source 15 and the seventh light source 17 is shorter than the distance between the fifth light source 15 and the eighth light source 18. As will be described later, the relative positions of these light sources can be changed.
[0028] As shown in Figures 2 and 3, the light source device 110 may further include a first mirror 31 and a second mirror 32.
[0029] As shown in Figure 2, the first laser beam 11L that passes through the first optical member 21 and the fourth laser beam 14L that is reflected by the first optical member 21 are reflected by the first mirror 31 and pass through the second mirror 32. The second laser beam 12L that passes through the second optical member 22 and the third laser beam 13L that is reflected by the second optical member 22 are reflected by the second mirror 32.
[0030] As shown in Figure 3, the fifth laser beam 15L that passed through the first optical member 21, and the eighth laser beam 18L that was reflected by the first optical member 21, are reflected by the first mirror 31 and pass through the second mirror 32. The sixth laser beam 16L that passed through the second optical member 22, and the seventh laser beam 17L that was reflected by the second optical member 22, are reflected by the second mirror 32.
[0031] The first mirror 31 is, for example, a total internal reflection mirror. The second mirror 32 is, for example, a reflective polarizing element. In this embodiment, wavelength synthesis is performed, followed by polarization synthesis.
[0032] As shown in Figures 2 and 3, the light source device 110 may further include an optical shaping member 40. The first laser beam 11L and the fourth laser beam 14L that have passed through the second mirror 32 pass through the optical shaping member 40. The second laser beam 12L and the third laser beam 13L that have been reflected by the second mirror 32 pass through the optical shaping member 40. The fifth laser beam 15L and the eighth laser beam 18L that have passed through the second mirror 32 pass through the optical shaping member 40. The sixth laser beam 16L and the seventh laser beam 17L that have been reflected by the second mirror 32 pass through the optical shaping member 40.
[0033] For example, the optical shaping member 40 includes a first lens 41 and a second lens 42. In one example, the first lens 41 is either a concave lens or a convex lens. In another example, the second lens 42 is the other of a concave lens or a convex lens. For example, at least one of the first lens 41 and the second lens 42 may be a cylindrical lens.
[0034] The light shaping member 40 shapes the light including the first to eighth laser beams 11L to 18L. The light shaping member 40 expands the width of the light including the first to eighth laser beams 11L to 18L in any direction, and the light is mixed.
[0035] As shown in Figures 2 and 3, the light source device 110 may further include a diffusion element 51. A cylindrical lens array, a microlens array, or a plate with a textured surface can be used as the diffusion element 51. The first to eighth laser beams 11L to 18L emitted from the optical shaping member 40 are incident on the diffusion element 51. The diffusion element 51 controls the emission angle of the light, including the first to eighth laser beams 11L to 18L.
[0036] As shown in Figures 2 and 3, the light source device 110 may further include a fly-eye lens 52. The first to eighth laser beams 11L to 18L emitted from the diffusion element 51 pass through the fly-eye lens 52. The fly-eye lens 52 further shapes the light, including the first to eighth laser beams 11L to 18L, into a substantially uniform light.
[0037] As shown in Figures 2 and 3, the light emitted from the fly-eye lens 52 is incident on the control element 81. The control element 81 includes, for example, a plurality of optical switches. The control element 81 may also include, for example, elements based on MEMS (Micro Electro Mechanical Systems). The control element 81 provides the light necessary to form the image to be displayed.
[0038] As shown in Figures 2 and 3, an imaging optical member 82 may be provided. The imaging optical member 82 forms an image of the light emitted from the control element 81. The imaging optical member 82 includes, for example, a projection lens.
[0039] Figures 4 to 7 are schematic diagrams illustrating the state of light according to the first embodiment. These diagrams schematically illustrate the state of light in a plane perpendicular to the direction of light propagation.
[0040] Figure 4 illustrates the state of laser light after it has passed through or reflected from the first optical member 21 and the second optical member 22, and before it is incident on the first mirror 31 and the second mirror 32. The first laser beam 11L and the fourth laser beam 14L overlap with each other. The second laser beam 12L and the third laser beam 13L overlap with each other. The fifth laser beam 15L and the eighth laser beam 18L overlap with each other. The sixth laser beam 16L and the seventh laser beam 17L overlap with each other. For example, in the state of laser light shown in Figure 4, since light sources with different wavelengths are arranged inverted in the up, down, left, and right directions, the green laser beam and the red laser beam overlap with each other in the upper right laser beam. The blue laser beam and the red laser beam overlap with each other in the upper left laser beam. The blue laser beam and the red laser beam overlap with each other in the lower right laser beam. The green laser beam and the red laser beam overlap with each other in the lower left laser beam. In contrast, when light sources with different wavelengths are arranged in the same orientation in the up, down, left, and right directions, the green laser beams in the upper right overlap with each other. The red laser beams in the upper left overlap with each other. The blue laser beams in the lower right overlap with each other. The red laser beams in the lower left overlap with each other. By arranging light sources with different wavelengths inverted in the up, down, left, and right directions, the wavelength distribution is not biased.
[0041] Figure 5 illustrates the state of light emitted from the second mirror 32. The first to fourth laser beams 11L to 14L overlap with each other. The fifth to eighth laser beams 15L to 18L overlap with each other. For example, in the laser light state shown in Figure 5, since light sources with different wavelengths are arranged inverted in the up-down and left-right directions, the green, red, and blue laser beams overlap in both the upper and lower laser beams. In contrast, if light sources with different wavelengths are arranged in the same direction in the up-down and left-right directions, the green and red laser beams overlap in the upper laser beam, and the blue and red laser beams overlap in the lower laser beam. In this embodiment, even in the laser light state shown in Figure 5, the wavelength distribution is not biased by arranging light sources with different wavelengths inverted in the up-down and left-right directions.
[0042] Figures 6 and 7 illustrate the state of light emitted from the optical shaping member 40. For example, the light irradiation area 10R, which includes the first to eighth laser beams 11L to 18L, has a roughly rectangular shape (including a square).
[0043] In one example, the light emitted from the photoshaping member 40 is substantially white. The light emitted from the photoshaping member 40 may be a color other than white. A uniform illumination area 10R is obtained.
[0044] As shown in Figures 1 to 3, the light source unit 10 may include a first sealing member 11M, a second sealing member 12M, a third sealing member 13M, and a fourth sealing member 14M. The first sealing member 11M seals the first light source 11 and the fifth light source 15. The second sealing member 12M seals the second light source 12 and the sixth light source 16. The third sealing member 13M seals the third light source 13 and the seventh light source 17. The fourth sealing member 14M seals the fourth light source 14 and the eighth light source 18. The first sealing member 11M, the second sealing member 12M, the third sealing member 13M, and the fourth sealing member 14M are spaced apart from each other.
[0045] It is preferable that the first sealing member 11M, the second sealing member 12M, the third sealing member 13M, and the fourth sealing member 14M are spaced apart from each other. The first sealing member 11M and the second sealing member 12M may be in contact with each other. The first sealing member 11M and the second sealing member 12M may be formed as a single unit. The third sealing member 13M and the fourth sealing member 14M may be in contact with each other. The third sealing member 13M and the fourth sealing member 14M may be formed as a single unit.
[0046] As shown in Figure 1, the light source unit 10 may include one or more other light sources 10x in addition to the first to eighth light sources 11 to 18. The other light sources 10x emit laser light. The laser light emitted from the other light source 10x may pass through or reflect off the first optical member 21 or the second optical member 22 and be incident on the first mirror 31 or the second mirror 32. The peak wavelength of the laser light emitted from the other light source 10x is arbitrary. By providing the other light source 10x, a higher luminous flux can be obtained. Furthermore, if light sources 10x of the same wavelength are provided in positions that are inverted vertically and horizontally, a higher luminous flux can be obtained while maintaining a uniform illuminance distribution. In Figures 4 to 6, the laser light emitted from the other light sources 10x is omitted.
[0047] Figure 8 is a schematic perspective view illustrating a light source device 110a according to the first embodiment. As shown in Figure 8, in the light source device 110a according to the embodiment, the light source unit 10 may include a plurality of first light sources 11 and a plurality of third light sources 13. The direction from one of the plurality of first light sources 11 to another of the plurality of first light sources 11 is along the third direction D3. The direction from one of the plurality of third light sources 13 to another of the plurality of third light sources 13 is along the third direction D3.
[0048] As shown in Figure 8, the light source unit 10 may include a plurality of fifth light sources 15 and a plurality of seventh light sources 17. The direction from one of the plurality of fifth light sources 15 to another of the plurality of fifth light sources 15 is along the third direction D3. The direction from one of the plurality of seventh light sources 17 to another of the plurality of seventh light sources 17 is along the third direction D3. The configuration of the light source device 110a, excluding the above, may be the same as the configuration of the light source device 110. Even with the light source device 110a, a light source device that can suppress the generation of speckle can be provided.
[0049] Figures 9 and 10 are schematic plan views illustrating the light source device 111 and display device 210 according to the first embodiment. As shown in Figure 9, in the light source device 111 according to this embodiment, the first laser beam 11L emitted from the first light source 11 is S-polarized 10S. The first laser beam 11L with S-polarization 10S is incident on the first optical member 21. The second laser beam 12L emitted from the second light source 12 is P-polarized 10P. The second laser beam 12L with P-polarization 10P is incident on the second optical member 22.
[0050] In P-polarized light 10P, the direction of vibration of the electric field follows the third direction D3. In S-polarized light 10S, the direction of vibration of the electric field is perpendicular to the direction of light propagation and intersects (e.g., orthogonal) with the direction of vibration of the electric field in P-polarized light 10P.
[0051] As shown in Figure 9, a phase element 61 may be provided. The phase element 61 is, for example, a λ / 2 plate. For example, the third laser beam 13L emitted from the third light source 13 is S-polarized 10S. The S-polarized 10S third laser beam 13L passes through the phase element 61 and is converted to P-polarized 10P. The P-polarized 10P third laser beam 13L is incident on the second optical member 22. For example, the fourth laser beam 14L emitted from the fourth light source 14 is P-polarized 10P. The P-polarized 10P fourth laser beam 14L passes through the phase element 61 and is converted to S-polarized 10S. The S-polarized 10S fourth laser beam 14L is incident on the first optical member 21.
[0052] As shown in Figure 10, the fifth laser beam 15L emitted from the fifth light source 15 is S-polarized 10S. The fifth laser beam 15L with S-polarization 10S is incident on the first optical member 21. The sixth laser beam 16L emitted from the sixth light source 16 is P-polarized 10P. The sixth laser beam 16L with P-polarization 10P is incident on the second optical member 22.
[0053] As shown in Figure 10, for example, the seventh laser beam 17L emitted from the seventh light source 17 is S-polarized 10S. The S-polarized 10S seventh laser beam 17L passes through the phase element 61 and is converted to P-polarized 10P. The seventh laser beam 17L converted to P-polarized 10P is incident on the second optical member 22. For example, the eighth laser beam 18L emitted from the eighth light source 18 is P-polarized 10P. The P-polarized 10P eighth laser beam 18L passes through the phase element 61 and is converted to S-polarized 10S. The eighth laser beam 18L converted to S-polarized 10S is incident on the first optical member 21.
[0054] When using light sources that emit different polarizations, the polarization can be aligned by providing the phase element 61, thereby performing polarization multiplexing.
[0055] Figure 11 is a schematic perspective view illustrating a light source device 120 according to the first embodiment. Figures 12 and 13 are schematic plan views illustrating the light source device 120 and display device 210 according to the first embodiment. As shown in Figures 11 to 13, the light source device 120 according to this embodiment includes a first optical member 21, a second optical member 22, and a light source unit 10. The light source unit 10 includes a first light source 11, a second light source 12, a third light source 13, a fourth light source 14, a fifth light source 15, a sixth light source 16, a seventh light source 17, and an eighth light source 18. In the light source device 120, the positions of light sources with different wavelengths are different from those in the light source device 110. The configuration of the light source device 120, apart from this, may be the same as that of the light source device 110.
[0056] As shown in Figure 12, in the light source device 120, the distance between the second light source 12 and the fourth light source 14 is shorter than the distance between the second light source 12 and the third light source 13. The distance between the second light source 12 and the fourth light source 14 is shorter than the distance between the first light source 11 and the fourth light source 14.
[0057] As shown in Figure 13, in the light source device 120, the distance between the sixth light source 16 and the eighth light source 18 is shorter than the distance between the sixth light source 16 and the seventh light source 17. The distance between the sixth light source 16 and the eighth light source 18 is shorter than the distance between the fifth light source 15 and the eighth light source 18.
[0058] As shown in Figure 12, the second laser beam 12L that passes through the second optical member 22, and the third laser beam 13L that is reflected by the second optical member 22, are reflected by the first mirror 31 and pass through the second mirror 32. The first laser beam 11L that passes through the first optical member 21, and the fourth laser beam 14L that is reflected by the first optical member 21, are reflected by the second mirror 32.
[0059] As shown in Figure 13, the sixth laser beam 16L that passed through the second optical member 22, and the seventh laser beam 17L that was reflected by the second optical member 22, are reflected by the first mirror 31 and pass through the second mirror 32. The fifth laser beam 15L that passed through the first optical member 21, and the eighth laser beam 18L that was reflected by the first optical member 21, are reflected by the second mirror 32.
[0060] As shown in Figure 12, the second laser beam 12L and the third laser beam 13L that have passed through the second mirror 32 pass through the optical shaping member 40. The first laser beam 11L and the fourth laser beam 14L that have been reflected by the second mirror 32 also pass through the optical shaping member 40.
[0061] As shown in Figure 13, the sixth laser beam 16L and the seventh laser beam 17L that have passed through the second mirror 32 pass through the optical shaping member 40. The fifth laser beam 15L and the eighth laser beam 18L that have been reflected by the second mirror 32 also pass through the optical shaping member 40.
[0062] In the light source device 120 as well, the angular multiplicity for each wavelength can be averaged, and a light source device that can suppress the generation of speckle can be provided.
[0063] Figure 14 is a schematic perspective view illustrating a light source device 120a according to the first embodiment. As shown in Figure 14, in the light source device 120a according to the embodiment, the light source unit 10 may include a plurality of first light sources 11 and a plurality of third light sources 13. The direction from one of the plurality of first light sources 11 to another of the plurality of first light sources 11 is along the third direction D3. The direction from one of the plurality of third light sources 13 to another of the plurality of third light sources 13 is along the third direction D3.
[0064] As shown in Figure 14, the light source unit 10 may include a plurality of fifth light sources 15 and a plurality of seventh light sources 17. The direction from one of the plurality of fifth light sources 15 to another of the plurality of fifth light sources 15 is along the third direction D3. The direction from one of the plurality of seventh light sources 17 to another of the plurality of seventh light sources 17 is along the third direction D3. The configuration of the light source device 120a, excluding the above, may be the same as the configuration of the light source device 120. Even with the light source device 120a, a light source device can be provided in which the angular multiplicity for each wavelength can be averaged and the generation of speckle can be suppressed.
[0065] In the light source devices 110a and 120a, a plurality of second light sources 12, a plurality of fourth light sources 14, a plurality of sixth light sources 16, and a plurality of eighth light sources 18 may be provided. The direction from one of the plurality of second light sources 12 to another of the plurality of second light sources 12 is along the third direction D3. The direction from one of the plurality of fourth light sources 14 to another of the plurality of fourth light sources 14 is along the third direction D3. The direction from one of the plurality of sixth light sources 16 to another of the plurality of sixth light sources 16 is along the third direction D3. The direction from one of the plurality of eighth light sources 18 to another of the plurality of eighth light sources 18 is along the third direction D3.
[0066] Figures 15 and 16 are schematic plan views illustrating the light source device 121 and display device 210 according to the first embodiment. As shown in Figure 15, for example, in the light source device 121 according to the embodiment, the first laser beam 11L with S polarization 10S is incident on the first optical member 21. The second laser beam 12L with P polarization 10P is incident on the second optical member 22.
[0067] As shown in Figure 15, a phase element 61 (for example, a λ / 2 plate) may be provided. For example, the third laser beam 13L emitted from the third light source 13 is S-polarized 10S. After passing through the phase element 61, it is converted to P-polarized 10P and the third laser beam 13L is incident on the second optical member 22. For example, the fourth laser beam 14L emitted from the fourth light source 14 is P-polarized 10P. After passing through the phase element 61, it is converted to S-polarized 10S and the fourth laser beam 14L is incident on the first optical member 21.
[0068] As shown in Figure 16, for example, the fifth laser beam 15L with S polarization 10S is incident on the first optical member 21. The sixth laser beam 16L with P polarization 10P is incident on the second optical member 22.
[0069] As shown in Figure 16, for example, the seventh laser beam 17L emitted from the seventh light source 17 is S-polarized 10S. The seventh laser beam 17L, converted to P-polarized 10P after passing through the phase element 61, is incident on the second optical member 22. For example, the eighth laser beam 18L emitted from the eighth light source 18 is P-polarized 10P. The eighth laser beam 18L, converted to S-polarized 10S after passing through the phase element 61, is incident on the first optical member 21.
[0070] In this embodiment, the maximum brightness value within the illumination area 10R is defined as 100%. The area within the illumination area 10R, excluding the portion where the brightness value is 10% or less of the maximum brightness value, is divided into 16 equal parts. For each of the 16 divided areas, the average brightness value in the area with the lowest average brightness value is defined as the first value. The average brightness value in the area with the highest average brightness value is defined as the second value. The ratio of the first value to the second value is defined as the first ratio. A high first ratio indicates high uniformity of the illuminance distribution. In this embodiment, in one example of a state where the illuminance distribution is uniform, the first ratio is 50% or more. In another example of a state where the illuminance distribution is uniform, the first ratio is 65% or more. In yet another example of a state where the illuminance distribution is uniform, it is 80% or more. If the first ratio is excessively low, the suppression of speckle generation may be insufficient.
[0071] (Second Embodiment) Figure 17 is a schematic plan view illustrating a light source device 140 and a display device 210 according to the second embodiment. As shown in Figure 17, the light source device 140 according to the embodiment includes a first optical member 21, a second optical member 22, and a light source unit 10. The light source unit 10 includes a first light source 11, a second light source 12, a third light source 13, and a fourth light source 14. The first light source 11 emits a first laser beam 11L having a first peak wavelength. The second light source 12 emits a second laser beam 12L. The second laser beam 12L has a second peak wavelength different from the first peak wavelength. The third light source 13 emits a third laser beam 13L having a first peak wavelength. The fourth light source 14 emits a fourth laser beam 14L having a second peak wavelength.
[0072] The first laser beam 11L passes through the first optical member 21. The second laser beam 12L passes through the second optical member 22. The third laser beam 13L is reflected by the second optical member 22. The fourth laser beam 14L is reflected by the first optical member 21.
[0073] In the light source device 140, the arrangement of light sources with different wavelengths is reversed. This configuration makes it easier to obtain uniform light. According to this embodiment, a light source device is provided that can suppress the generation of speckle.
[0074] In the light source device 140, the first laser beam 11L that has passed through the first optical member 21 is reflected by the first mirror 31 and passes through the second mirror 32. The fourth laser beam 14L that has been reflected by the first optical member 21 is reflected by the first mirror 31 and passes through the second mirror 32. The second laser beam 12L that has passed through the second optical member 22 is reflected by the second mirror 32. The third laser beam 13L that has been reflected by the second optical member 22 is reflected by the second mirror 32. These laser beams pass through the optical shaping member 40 and are then incident on the diffusion element 51.
[0075] (Third embodiment) The third embodiment relates to a display device. For example, the display device 210 according to the embodiment (see, for example, Figures 2 and 3) includes a light source device according to the first or second embodiment (light source device 110 in the example shown in Figures 2 and 3) and a control element 81. As already described, light emitted from the light source device 110 is incident on the control element 81. The display device 210 may also include an imaging optical member 82. The imaging optical member 82 forms an image of the light emitted from the control element 81. The display device 210 is, for example, a projector. Since the display device 210 includes a light source device according to the first or second embodiment, it is possible to provide a display device that can display with suppressed speckle generation.
[0076] The embodiments may include the following items. (Section 1) First optical component and The second optical component and Light source section, Equipped with, The aforementioned light source unit is A first light source that emits a first laser beam having a first peak wavelength, A second light source that emits a second laser beam having a second peak wavelength different from the first peak wavelength, A third light source that emits a third laser beam having a third peak wavelength that is different from the first peak wavelength and also different from the second peak wavelength, A fourth light source that emits a fourth laser beam having the second peak wavelength, A fifth light source that emits a fifth laser beam having the third peak wavelength, A sixth light source that emits a sixth laser beam having the second peak wavelength, A seventh light source that emits a seventh laser beam having the first peak wavelength, An eighth light source that emits an eighth laser beam having the second peak wavelength, Includes, The first laser beam passes through the first optical member, The second laser beam passes through the second optical member, The third laser beam is reflected by the second optical component, The fourth laser beam is reflected by the first optical member, The fifth laser beam passes through the first optical member, The sixth laser beam passes through the second optical member, The seventh laser beam is reflected by the second optical component, The aforementioned 8th laser beam is reflected by the aforementioned 1st optical component in a light source device.
[0077] (Section 2) The second peak wavelength is longer than the first peak wavelength. The light source device according to item 1, wherein the first peak wavelength is longer than the third peak wavelength.
[0078] (Section 3) The direction from the first light source to the second light source is along the first direction, The direction from the third light source to the fourth light source follows the second direction which intersects the first direction. The direction from the fifth light source to the sixth light source is along the first direction, The direction from the seventh light source to the eighth light source is along the second direction, The direction from the fifth light source to the first light source is along a third direction that intersects a plane including the first and second directions. The direction from the sixth light source to the second light source is along the third direction, The direction from the seventh light source to the third light source is along the third direction, The light source device according to item 1 or 2, wherein the direction from the eighth light source to the fourth light source is along the third direction.
[0079] (Section 4) The first laser light is emitted from the first light source along the second direction, The second laser beam is emitted from the second light source along the second direction, The third laser beam is emitted from the third light source along the first direction, The fourth laser beam is emitted from the fourth light source along the first direction, The fifth laser beam is emitted from the fifth light source along the second direction, The sixth laser beam is emitted from the sixth light source along the second direction, The seventh laser beam is emitted from the seventh light source along the first direction, The light source device according to item 3, wherein the eighth laser beam is emitted from the eighth light source along the first direction.
[0080] (Section 5) The light source device according to any one of claims 1 to 4, wherein the distance between the first light source and the third light source is shorter than the distance between the first light source and the fourth light source, and shorter than the distance between the second light source and the third light source.
[0081] (Section 6) The light source device according to any one of claims 1 to 4, wherein the distance between the second light source and the fourth light source is shorter than the distance between the second light source and the third light source, and shorter than the distance between the first light source and the fourth light source.
[0082] (Section 7) Further comprising a first mirror and a second mirror, The first laser beam that has passed through the first optical member, and the fourth laser beam that has been reflected by the first optical member, are reflected by the first mirror and pass through the second mirror. The second laser beam that has passed through the second optical member, and the third laser beam that has been reflected by the second optical member, are reflected by the second mirror. The fifth laser beam that has passed through the first optical member, and the eighth laser beam that has been reflected by the first optical member, are reflected by the first mirror and pass through the second mirror. The light source device according to any one of claims 1 to 6, wherein the sixth laser light that has passed through the second optical member and the seventh laser light that has been reflected by the second optical member are reflected by the second mirror.
[0083] (Section 8) Further equipped with optical shaping components, The light source device according to item 7, wherein the first laser beam and the fourth laser beam that have passed through the second mirror, the second laser beam and the third laser beam that have been reflected by the second mirror, the fifth laser beam and the eighth laser beam that have passed through the second mirror, and the sixth laser beam and the seventh laser beam that have been reflected by the second mirror pass through the optical shaping member.
[0084] (Section 9) Further comprising a first mirror and a second mirror, The second laser beam that has passed through the second optical member, and the third laser beam that has been reflected by the second optical member, are reflected by the first mirror and pass through the second mirror. The first laser beam that has passed through the first optical member and the fourth laser beam that has been reflected by the first optical member are reflected by the second mirror. The sixth laser beam that has passed through the second optical member, and the seventh laser beam that has been reflected by the second optical member, are reflected by the first mirror and pass through the second mirror. The light source device according to any one of claims 1 to 6, wherein the fifth laser beam that has passed through the first optical member and the eighth laser beam that has been reflected by the first optical member are reflected by the second mirror.
[0085] (Section 10) Further equipped with optical shaping components, The light source device according to item 9, wherein the second laser beam and the third laser beam that have passed through the second mirror, the first laser beam and the fourth laser beam that have been reflected by the second mirror, the sixth laser beam and the seventh laser beam that have passed through the second mirror, and the fifth laser beam and the eighth laser beam that have been reflected by the second mirror pass through the optical shaping member.
[0086] (Section 11) Further equipped with a diffusion element, The light source device according to item 8 or 10, wherein the first to eighth laser beams emitted from the optical shaping member are incident on the diffusion element.
[0087] (Section 12) Equipped with a fly-eye lens, The light source device according to item 11, wherein the first to eighth laser beams emitted from the diffusion element pass through the fly-eye lens.
[0088] (Section 13) The light source unit includes a plurality of first light sources and a plurality of third light sources, The direction from one of the plurality of first light sources to another of the plurality of first light sources is the 3 Along the direction, The direction from one of the plurality of third light sources to another of the plurality of third light sources is the 3 A light source device as described in item 3 or 4, aligned with the direction.
[0089] (Section 14) A first sealing member that seals the first light source and the fifth light source, A second sealing member that seals the second light source and the sixth light source, A third sealing member that seals the third light source and the seventh light source, A fourth sealing member that seals the fourth light source and the eighth light source, Furthermore, The light source device according to any one of claims 1 to 13, wherein the first sealing member, the second sealing member, the third sealing member, and the fourth sealing member are spaced apart from each other.
[0090] (Section 15) First optical component and The second optical component and Light source section, Equipped with, The aforementioned light source unit is A first light source that emits a first laser beam having a first peak wavelength, A second light source that emits a second laser beam having a second peak wavelength different from the first peak wavelength, A third light source that emits a third laser beam having the first peak wavelength, A fourth light source that emits a fourth laser beam having the second peak wavelength, Includes, The first laser beam passes through the first optical member, The second laser beam passes through the second optical member, The third laser beam is reflected by the second optical component, The light source device in which the aforementioned fourth laser beam is reflected by the aforementioned first optical component.
[0091] (Section 16) A light source device as described in any one of items 1 to 14, A control element into which light emitted from the aforementioned light source device is incident, An imaging optical member that forms an image of the light emitted from the control element, A display device equipped with the following features.
[0092] According to the embodiment, a light source device and a display device that can suppress the occurrence of speckle can be provided.
[0093] In this specification, "perpendicular" does not refer only to strictly perpendicular lines, but also includes variations in the manufacturing process, for example, and includes cases that are substantially perpendicular.
[0094] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, with regard to the specific components of a light source, wavelength multiplexing member, element, and mirror included in a light source device, the present invention can be implemented in the same manner and similar effects can be obtained by appropriately selecting components from the range known to those skilled in the art, as long as such components are included within the scope of the present invention.
[0095] Combinations of two or more elements from any of the specific examples, to the extent technically feasible, are also included within the scope of the present invention, insofar as they encompass the gist of the invention.
[0096] Furthermore, all light source devices and display devices that can be implemented by those skilled in the art by appropriately modifying the design based on the above-described embodiments of the present invention also fall within the scope of the present invention, insofar as they encompass the gist of the present invention.
[0097] Furthermore, within the scope of the concept of the present invention, a person skilled in the art could conceive of various modifications and alterations, and these modifications and alterations are also understood to fall within the scope of the present invention. [Explanation of symbols]
[0098] 10…Light source unit, 10A, 10B…1st and 2nd modules, 10P…P-polarized light, 10S…S-polarized light, 10x…Light source, 11~18…1st to 8th light sources, 11L~18L…1st to 8th laser beams, 11M~14M…1st to 4th sealing members, 21, 22…1st and 2nd optical members, 31, 32…1st and 2nd mirrors, 40…Optical shaping member, 41, 42…1st and 2nd lenses, 51…Diffusion element, 52…Fly-eye lens, 61…Phase element, 81…Control element, 82…Imaging optical member, 110, 110a, 111, 120, 120a, 121, 140…Light source device, 210…Display device, D1~D3…1st to 3rd directions
Claims
1. First optical component and The second optical component and Light source section, Equipped with, The aforementioned light source unit is A first light source that emits a first laser beam having a first peak wavelength, A second light source that emits a second laser beam having a second peak wavelength different from the first peak wavelength, A third light source that emits a third laser beam having a third peak wavelength that is different from the first peak wavelength and also different from the second peak wavelength, A fourth light source that emits a fourth laser beam having the second peak wavelength, A fifth light source that emits a fifth laser beam having the third peak wavelength, A sixth light source that emits a sixth laser beam having the second peak wavelength, A seventh light source that emits a seventh laser beam having the first peak wavelength, An eighth light source that emits an eighth laser beam having the second peak wavelength, Includes, The first laser beam passes through the first optical member, The second laser beam passes through the second optical member, The third laser beam is reflected by the second optical member, The fourth laser beam is reflected by the first optical member, The fifth laser beam passes through the first optical member, The sixth laser beam passes through the second optical member, The seventh laser beam is reflected by the second optical member, The eighth laser beam is reflected by the first optical member in the light source device.
2. The second peak wavelength is longer than the first peak wavelength. The light source device according to claim 1, wherein the first peak wavelength is longer than the third peak wavelength.
3. The direction from the first light source to the second light source is along the first direction, The direction from the third light source to the fourth light source is along the second direction which intersects with the first direction. The direction from the fifth light source to the sixth light source is along the first direction, The direction from the seventh light source to the eighth light source is along the second direction, The direction from the fifth light source to the first light source is along a third direction that intersects a plane including the first and second directions. The direction from the sixth light source to the second light source is along the third direction, The direction from the seventh light source to the third light source is along the third direction, The light source device according to claim 1, wherein the direction from the eighth light source to the fourth light source is along the third direction.
4. The first laser light is emitted from the first light source along the second direction, The second laser light is emitted from the second light source along the second direction, The third laser beam is emitted from the third light source along the first direction, The fourth laser beam is emitted from the fourth light source along the first direction, The fifth laser beam is emitted from the fifth light source along the second direction, The sixth laser beam is emitted from the sixth light source along the second direction, The seventh laser beam is emitted from the seventh light source along the first direction, The light source device according to claim 3, wherein the eighth laser beam is emitted from the eighth light source along the first direction.
5. The light source device according to claim 1, wherein the distance between the first light source and the third light source is shorter than the distance between the first light source and the fourth light source, and shorter than the distance between the second light source and the third light source.
6. The light source device according to claim 1, wherein the distance between the second light source and the fourth light source is shorter than the distance between the second light source and the third light source, and shorter than the distance between the first light source and the fourth light source.
7. Further comprising a first mirror and a second mirror, The first laser beam that has passed through the first optical member, and the fourth laser beam that has been reflected by the first optical member, are reflected by the first mirror and pass through the second mirror. The second laser beam that has passed through the second optical member, and the third laser beam that has been reflected by the second optical member, are reflected by the second mirror. The fifth laser beam that has passed through the first optical member, and the eighth laser beam that has been reflected by the first optical member, are reflected by the first mirror and pass through the second mirror. The light source device according to claim 1, wherein the sixth laser light that has passed through the second optical member and the seventh laser light that has been reflected by the second optical member are reflected by the second mirror.
8. Further equipped with optical shaping components, The light source device according to claim 7, wherein the first laser beam and the fourth laser beam that have passed through the second mirror, the second laser beam and the third laser beam that have been reflected by the second mirror, the fifth laser beam and the eighth laser beam that have passed through the second mirror, and the sixth laser beam and the seventh laser beam that have been reflected by the second mirror pass through the optical shaping member.
9. Further comprising a first mirror and a second mirror, The second laser beam that has passed through the second optical member, and the third laser beam that has been reflected by the second optical member, are reflected by the first mirror and pass through the second mirror. The first laser beam that has passed through the first optical member and the fourth laser beam that has been reflected by the first optical member are reflected by the second mirror. The sixth laser beam that has passed through the second optical member, and the seventh laser beam that has been reflected by the second optical member, are reflected by the first mirror and pass through the second mirror. The light source device according to claim 1, wherein the fifth laser beam that has passed through the first optical member and the eighth laser beam reflected by the first optical member are reflected by the second mirror.
10. Further equipped with optical shaping components, The light source device according to claim 9, wherein the second laser beam and the third laser beam that have passed through the second mirror, the first laser beam and the fourth laser beam that have been reflected by the second mirror, the sixth laser beam and the seventh laser beam that have passed through the second mirror, and the fifth laser beam and the eighth laser beam that have been reflected by the second mirror pass through the optical shaping member.
11. Further equipped with a diffusion element, The light source device according to claim 8, wherein the first to eighth laser beams emitted from the optical shaping member are incident on the diffusion element.
12. Equipped with a fly-eye lens, The light source device according to claim 11, wherein the first to eighth laser beams emitted from the diffusion element pass through the fly-eye lens.
13. The light source unit includes a plurality of first light sources and a plurality of third light sources, The direction from one of the plurality of first light sources to another of the plurality of first light sources is along the third direction, The light source device according to claim 3, wherein the direction from one of the plurality of third light sources to another of the plurality of third light sources is along the third direction.
14. A first sealing member that seals the first light source and the fifth light source, A second sealing member that seals the second light source and the sixth light source, A third sealing member that seals the third light source and the seventh light source, A fourth sealing member that seals the fourth light source and the eighth light source, Furthermore, The light source device according to claim 1, wherein the first sealing member, the second sealing member, the third sealing member, and the fourth sealing member are spaced apart from each other.
15. First optical component and The second optical component and Light source section, Equipped with, The aforementioned light source unit is A first light source that emits a first laser beam having a first peak wavelength, A second light source that emits a second laser beam having a second peak wavelength different from the first peak wavelength, A third light source that emits a third laser beam having the first peak wavelength, A fourth light source that emits a fourth laser beam having the second peak wavelength, Includes, The first laser beam passes through the first optical member, The second laser beam passes through the second optical member, The third laser beam is reflected by the second optical member, A light source device in which the fourth laser beam is reflected by the first optical member.
16. A light source device according to any one of claims 1 to 14, A control element into which light emitted from the aforementioned light source device is incident, An imaging optical member that forms an image of the light emitted from the control element, A display device equipped with the following features.