Light source device and projector

Abstract

To reduce the size of a light source device and a projector.SOLUTION: A light source device 11 include a light emitter 12 for emitting light, and a scan element 13 for scanning the light. A progress vector of the light includes only a positive component for a component perpendicular to a surface of the scan element 13. The light emitter 12 and the scan element 13 are thus unified.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a light source device and a projector incorporating the light source device. [Background technology]

[0002] Conventionally, projectors have been used as image projection devices that project images such as computer screens and video images onto a screen. In these projectors, light emitted from a light source device is reflected by a MEMS (Micro Electro Mechanical Systems) mirror and scanned to project an image onto the screen (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-185943 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional projectors, the light source and the mirror are arranged at positions apart from each other in a configuration in which light from the light source is reflected by a mirror, making it difficult to reduce the size of the projector. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, the light source device of the present invention is characterized in that it comprises a light-emitting element that emits light and a scanning element that scans the light, and the traveling vector of the light includes only positive components in a perpendicular direction relative to the surface of the scanning element.

[0006] In the light source device according to the present invention, the scanning element may rotate in two axial directions.

[0007] In the light source device according to the present invention, a light emitting element may be mounted on the scanning element.

[0008] In the light source device according to the present invention, the scanning element may include a light transmitting portion, and light emitted from the light emitting element may be transmitted through the light transmitting portion.

[0009] In the light source device according to the present invention, a light refraction element may be provided in the light transmitting portion.

[0010] In addition, the light source device of the present invention may be such that the scanning element comprises a fixed frame, a movable frame, and a movable part, the movable frame is connected to the inside of the fixed frame via a first beam formed on both sides of the movable frame, the movable part is connected to the inside of the movable frame via a second beam formed on both sides of the movable part, and the direction of the first beam is perpendicular to the direction of the second beam.

[0011] A projector according to the present invention includes the light source device and a control unit. Effect of the Invention

[0012] According to the present invention, it is possible to integrate a light emitting element and a scanning element, and to provide a small light source device and projector. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a block diagram showing the configuration of a projector according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram for explaining the operation of the light source device according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a diagram showing the configuration of a light source device according to a first embodiment of the present invention. [Figure 4] FIG. 4 is a schematic side view for explaining the operation of the light source device according to the first embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram showing the configuration of a light source device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] <First embodiment> A light source device and a projector according to a first embodiment of the present invention will be described with reference to FIGS.

[0015] <Light source device and projector configuration> As shown in Fig. 1, the projector 1 according to this embodiment includes a light source device 1_1 and a control unit 1_4. The light source device 1_1 includes a light emitting element 1_2 and a scanning element 1_3, and the control unit 1_4 includes a light emitting element driving power supply 1_5 and a scanning element driving power supply 1_6. The light emitting element 1_2 is connected to the light emitting element driving power supply 1_5, and the scanning element 1_3 is connected to the scanning element driving power supply 1_6.

[0016] <Light source operation> The operation of the light source device 1_1 in the projector 1 according to this embodiment will be described with reference to Fig. 2(a). For comparison, Fig. 2(b) shows the configuration of a light source device of a conventional projector.

[0017] Here, the direction perpendicular to the emission surface (surface) of the light source device 1_1 or the scanning element 1_3' is defined as the Z direction. The positive direction (Z+ direction) in the Z direction is defined as the direction toward the side where light is emitted from the light source device 1_1 or the scanning element 1_3'. The negative direction (Z- direction) in the Z direction is defined as the direction opposite to the side where light is emitted from the light source device 1_1 or the scanning element 1_3'.

[0018] In the configuration of the light source device of the conventional projector, the emitted light L from the light emitting element 1_2' is reflected by the scanning element 1_3', and the reflected light R is scanned by driving (rotating) the scanning element 1_3'.

[0019] In this configuration, as shown in FIG. 2(b), the traveling vector of the emitted light L from the light-emitting element 1_2' includes a negative Z-direction component (Z-), and the traveling vector of the reflected light R from the scanning element 1_3' includes a positive Z-direction component (Z+).

[0020] Thus, the travel vector of the light in this configuration includes a negative Z component (Z-) and a positive Z component (Z+).

[0021] Therefore, in the configuration of the light source device of the conventional projector, since the reflected light R is utilized, a certain distance is required between the light emitting element 1_2' and the scanning element 1_3', which makes it difficult to reduce the size of the projector.

[0022] On the other hand, in the light source device 1_1 of the projector 1 according to the present embodiment, the light emitting element 1_2 and the scanning element 1_3 are integrated, so that the emitted light L or the transmitted light T is used without using reflected light. The emitted light L or the transmitted light T is scanned and projected by driving (rotating) the scanning element 1_3.

[0023] In this configuration, as shown in FIG. 2(a), the traveling vector of the emitted light L or transmitted light T of the light source device 1_1 does not include a negative Z direction component (Z-), but only includes a positive Z direction component (Z+).

[0024] Therefore, in the light source device 1_1 according to the present embodiment, since reflected light is not used and the light emitting element 1_2 and the scanning element 1_3 are integrated, the projector can be made compact.

[0025] <First Example> A light source device and a projector according to a first embodiment of the present invention will be described with reference to FIGS.

[0026] <Light source device and projector configuration> A projector 10 according to this embodiment has the same configuration as that of the first embodiment. A light source device 11 according to this embodiment includes a light emitting element 12 and a scanning element 13.

[0027] 3(a) and (b) respectively show a schematic bird's-eye view and a schematic front view of a light source device 11 according to this embodiment. In the light source device 11, a light-emitting element 12 is mounted on a scanning element 13 as shown in FIG.

[0028] An electromagnetically driven MEMS is used for the scanning element 13. The scanning element 13 includes a movable frame 132 formed to be rotatable about a first axis 130_1, a fixed frame 131 supporting the movable frame 132, and a movable part 133 formed to be rotatable about a second axis 130_2 perpendicular to the first axis 130_1.

[0029] Also, a first magnet (N pole) 135_1 and a second magnet (S pole) 135_2 for forming a magnetic field in a direction between the first axis 130_1 and the second axis 130_2 are arranged on both sides of the fixed frame 131. For example, the N pole of the first magnet 135_1 and the S pole of the second magnet 135_2 are arranged on a diagonal line of the fixed frame 131. The first magnet (N pole) 135_1 and the second magnet (S pole) 135_2 can be formed of, for example, a permanent magnet or an electromagnet.

[0030] The movable frame 132 is connected to the inside of the fixed frame 131 via first beams 134_1 formed on both sides of the movable frame 132 in the direction of the first axis 130_1.

[0031] 3(b), a first drive coil 136_1 for rotating the movable frame 132 about the first axis 130_1 is disposed on the movable frame 132. For example, the first drive coil 136_1 is configured by being wound so as to make a plurality of turns within the plane of the movable frame 132, one end of which is connected to a first electrode 137_1 of the fixed frame 131 via a first beam 134_1, and the other end of which is connected to a second electrode 137_2 of the fixed frame 131 via the first beam 134_1.

[0032] A first signal for driving the movable frame 132 is applied to the first driving coil 136_1. When the first signal is applied to the first driving coil 136_1, a Lorentz force generated by a magnetic field formed by the first magnet (N pole) 135_1 and the second magnet (S pole) 135_2 and a current flowing through the first driving coil 136_1 drives the movable frame 132 to rotate about the first shaft 130_1 as a central axis.

[0033] On the other hand, the movable part 133 is disposed inside the movable frame 132 and connected to the movable frame 132. The movable part 133 is connected to the inside of the movable frame 132 via second beams 134_2 formed on both sides of the movable part 133 in the direction of the second axis 130_2.

[0034] Here, the direction of the first axis 130_1 and the direction of the second axis 130_2 are perpendicular to each other, and therefore the extension lines of the first beam 134_1 and the second beam 134_2 are also perpendicular to each other.

[0035] 3(b), a second drive coil 136_2 for rotating the movable part 133 about the second shaft 130_2 as a central axis is disposed in the movable part 133. For example, the second drive coil 136_2 is configured by being wound so as to make a plurality of turns within the plane of the movable part 133, and one end of the second drive coil 136_2 is connected to a third electrode 137_3 of the fixed frame 131 via the first beam 134_1 and the second beam 134_2, and the other end of the second drive coil 136_2 is connected to a fourth electrode 137_4 of the fixed frame 131 via the first beam 134_1 and the second beam 134_2.

[0036] A second signal for driving the movable part 133 is applied to the second driving coil 136_2. When the second signal is applied to the second driving coil 136_2, a Lorentz force generated by a magnetic field formed by the first magnet (N pole) 135_1 and the second magnet (S pole) 135_2 and a current flowing through the second driving coil 136_2 drives the movable part 133 to rotate about the second shaft 130_2 as a central axis.

[0037] The light emitting element 12 is mounted on a movable part 133 of the scanning element 13. The light emitting element 12 is composed of a red light source element that emits red laser light, a green light source element that emits green laser light, and an element that emits blue laser light.

[0038] For example, the red light source element, the green light source element, and the blue light source element are semiconductor lasers (LD) having central wavelengths of 630 nm, 530 nm, and 430 nm, respectively.

[0039] In this way, the light emitting element 12 can emit light in the red wavelength range, light in the green wavelength range, and light in the blue wavelength range, and these lights are combined to change the chromaticity.

[0040] In projector 10 according to this embodiment, the light emitting element driving power supply includes a red light source driving power supply, a green light source driving power supply, and a blue light source driving power supply, which respectively drive the red light source elements, green light source elements, and blue light source elements.

[0041] By changing the drive current for each of the red light source element, green light source element, and blue light source element, the amount of light (light intensity) of each is changed, and the chromaticity of the combined light is changed.

[0042] <Light source operation> The light emitted from the light emitting element 12 scans in the horizontal and vertical directions by driving the scanning element 13 and rotating it about the second axis 130_2 and the first axis 130_1 as central axes, resulting in an image being projected two-dimensionally on the screen.

[0043] For example, when the scanning element 13 is rotated about the second axis 130_2 to horizontally scan the emitted light of the light emitting element 12, it is desirable to drive it with a high frequency signal in order to scan the emitted light at high speed.

[0044] Therefore, when the movable part 133 of the scanning element 13 is driven in the horizontal direction, a high-frequency signal is used as the second signal applied to the second driving coil 136_2 from the scanning element driving power supply. Here, the movable part 133 and the second beam 134_2 are designed to have mass and elastic rigidity suitable for high-frequency vibration, respectively.

[0045] Also, for example, when the scanning element 13 is rotated about the first axis 130_1 as the central axis to scan the emitted light of the light-emitting element 12 in the vertical direction, it is not necessary to scan the emitted light in the vertical direction at high speed, so it may be driven by a low-frequency signal.

[0046] Therefore, when driving the movable frame 132 of the scanning element 13 in the vertical direction, a low-frequency signal is used as the first signal applied to the first driving coil 136_1 from the scanning element driving power supply. Here, the movable frame 132 and the first beam 134_1 are designed to have mass and elastic rigidity suitable for low-frequency vibration, respectively.

[0047] In this way, the light source device 11 according to this embodiment can scan the emitted light from the light emitting element 12 in the horizontal and vertical directions by driving the scanning element 13 to rotate it about the second axis 130_2 and the first axis 130_1 as central axes.

[0048] Furthermore, in light source device 11 according to this embodiment, the light emitted from light emitting element 12 is scanned and projected without reflecting the light emitted from the light emitting element as in the conventional light source device. Therefore, the light traveling vector in light source device 11 according to this embodiment includes only a positive component (Z+ direction component) in the perpendicular direction component to the surface of scanning element 13 as shown in FIG.

[0049] According to the light source device and projector of this embodiment, the light emitting element and the scanning element can be integrated, so that the light source device and the projector can be made compact.

[0050] <Second Example> A projector according to a second embodiment of the present invention will be described with reference to FIG.

[0051] <Light source device and projector configuration> The projector 20 according to the present embodiment has a similar configuration to the projector 10 according to the first embodiment.

[0052] 5(a) and (b) are a schematic bird's-eye view and a schematic side view, respectively, of a light source device 21 according to this embodiment. The light source device 21 includes a support base 27, a scanning element 23, and a light-emitting element 22, as shown in FIG.

[0053] In the light source device 21, the scanning element 23 is disposed above the light emitting element 22. As an example, as shown in FIG. 5, the light emitting element 22 is mounted on the upper surface of the bottom wall portion of the support base 27, and the scanning element 23 is disposed above the light emitting element 22.

[0054] The scanning element 23 includes a light transmitting portion 238 on the movable portion 233. A transmission plate such as a plate-shaped glass or a lens is provided in the light transmitting portion 238. The light transmitting portion 238 may be disposed on the entire surface of the movable portion 233 or may be disposed on a part of the movable portion 233, as long as the light emitted from the light emitting element 22 is transmitted therethrough.

[0055] In the scanning element 23, the configuration of the driving mechanism and the like other than the light transmitting portion 238 is similar to that of the first embodiment.

[0056] The configuration of the light emitting element 22 is similar to that of the first embodiment.

[0057] <Light source operation> As shown in Fig. 5(b), the emitted light L of the light-emitting element 22 passes through the light-transmitting portion 238 of the scanning element 23, and the transmitted light T is scanned by driving the scanning element 23 and projected onto a screen (not shown). Fig. 5(b) shows a manner of rotation of the scanning element 23 about the first axis 230_1, but the scanning element 23 also rotates in the same manner about the second axis 230_2.

[0058] When the lens 239 is provided in the light transmitting portion 238, the emitted light L of the light emitting element 22 is transmitted and refracted through the light transmitting portion 238 and the lens 239, and the transmitted light T is emitted from the scanning element 23. As a result, since the refraction angle at the lens 239 is larger in this embodiment than in the case where a transmitting plate is provided and in the first embodiment, the scanning range of the transmitted light T can be expanded. Here, the same effect can be achieved even if an element that refracts light (light refraction element), such as a prism, is provided other than a lens.

[0059] In addition, a half mirror, a polarizing plate, etc. may be provided in the light transmitting portion 238. Furthermore, by using a diffraction grating, a photonic crystal, etc., it is possible to change the color by tilting the scanning element even with a single color light source. Furthermore, an optical element that utilizes the transmission of light, such as an element related to holography, may be provided.

[0060] In addition, a blind structure may be provided in the light transmitting portion 238. For example, a blind structure in which light transmitting portions and light blocking portions are alternately arranged is used. The amount of light passing through the blind structure can be changed by rotating the scanning element.

[0061] In this way, the light source device 21 according to this embodiment can scan the light emitted from the light emitting element 22 in the horizontal and vertical directions by driving the scanning element 23 and rotating it about the second axis and the first axis as the central axis.

[0062] Furthermore, in the light source device 21 according to this embodiment, unlike the conventional light source device, the light emitted from the light emitting element 22 is not reflected, but the light emitted L from the light emitting element 22 is transmitted through the scanning element 23 and projected. Therefore, the traveling vector of the light in the light source device 21 according to this embodiment includes only a positive component (Z+ direction component) in the perpendicular direction component with respect to the surface of the scanning element 23.

[0063] According to the projector of this embodiment, the light emitting element and the scanning element can be integrated, so that the projector can be made compact.

[0064] In the embodiment and examples of the present invention, an example has been shown in which an electromagnetically driven MEMS is used as the scanning element, but an electrostatically driven MEMS, a piezoelectrically driven MEMS, or the like may also be used.

[0065] When using an electrostatically actuated MEMS, instead of the magnets in the embodiments of the present invention, electrodes for capacitance can be provided in the opposing parts of the fixed frame and the movable frame and in the opposing parts of the movable frame and the movable part.

[0066] Furthermore, when a piezoelectrically driven MEMS is used, piezoelectric elements may be provided on the first beam and the second beam instead of the magnets in the embodiments of the present invention.

[0067] In the embodiment and examples of the present invention, examples of the structure, dimensions, materials, etc. of each component in the configuration of the light source device and projector are shown, but the present invention is not limited to these. Anything that can exert the function and effect of the projector may be used. [Industrial Applicability]

[0068] The present invention can be applied to a projection type projector and an image display device. [Explanation of symbols]

[0069] 10. Projector 11 Light source device 12 Light emitting element 13 Scanning element 131 Fixed Frame 132 Movable Frame 133 Moving parts 134_1, 134_2 beam 135_1, 135_2 Magnets 136_1, 136_2 drive coil 137_1, 137_2, 137_3, 137_4 electrode 1_4 Control section 1_5 Light emitting element drive power supply 1_6 Scanning element drive power supply

Claims

1. A light emitting element that emits light; a scanning element for scanning the light, the light propagation vector includes only positive components in a direction perpendicular to a surface of the scanning element; The scanning element rotates in two axial directions, the scanning element includes a fixed frame, a movable frame, a movable portion, a first magnet, a second magnet, a first drive coil, and a second drive coil; The movable frame is connected to the fixed frame via first beams formed on both sides of the movable frame; the movable portion is connected to an inside of the movable frame via second beams formed on both sides of the movable portion; the direction of the first beam is perpendicular to the direction of the second beam; the N pole of the first magnet and the S pole of the second magnet are disposed diagonally on the fixed frame, the first drive coil is wound and arranged so as to make a plurality of turns within a plane of the movable frame; the second drive coil is wound and arranged so as to make a plurality of turns within a plane of the movable portion, the scanning element comprises a light transmitting portion; The light emitted from the light-emitting element disposed at a predetermined distance from one surface of the scanning element passes through the light-transmitting portion and is emitted from the other surface of the scanning element. A light source device characterized by:

2. A light refraction element is provided in the light transmitting portion.

2. The light source device according to claim 1.

3. The light source device according to claim 1 or 2, Control unit and A projector comprising:

Images