Optical block and image display device

Abstract

To provide an optical block for holding a plurality of optical components so as to suppress positional deviation of the optical components due to a temperature change, and an image display device to which a configuration of the optical block is applied.SOLUTION: An optical block includes: a base member 10; a mirror 31 (first optical component) fixed to a first installation surface of the base member 10 with an adhesive 61 (first adhesive); a mirror 32 (second optical component) fixed to a second installation surface facing the first installation surface of the base member 10 with an adhesive 62 (second adhesive); and an adhesive 63 (third adhesive) that is interposed between the mirror 31 and the mirror 32, and suppresses, by expansion or contraction due to a temperature change, displacement occurring in the mirror 31 and the mirror 32 by expansion or contraction due to a temperature change of the adhesive 61 and the adhesive 62.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an optical block in which a plurality of optical components are installed on a base member, and an image display device that displays an image using the plurality of optical components.

Background Art

[0002] Conventionally, as image display devices that scan light to display an image, a head-up display and a head-mounted display are known. In these devices, light modulated by a video signal is scanned in the horizontal and vertical directions to display an image for one frame. For example, in order to scan light in each direction, two MEMS mirrors are used, and an optical system for guiding light to these MEMS mirrors is arranged. A plurality of optical components constituting the optical system are position-adjusted on a base member so as to properly guide light, and are fixed to the base member with an adhesive.

[0003] Patent Document 1 below describes a configuration for preventing the relative positional relationship of the light beams of semiconductor lasers from shifting due to deformation caused by a change in ambient temperature in a pickup device using two semiconductor lasers. In this configuration, two semiconductor lasers and two coupling lenses for guiding the laser light emitted from these semiconductor lasers onto a recording medium are respectively held by a plurality of holding members. Then, the arrangement, shape, and material of each holding member are adjusted so that the amount and direction of displacement of the optical axis of the semiconductor laser caused by the deformation of each holding member due to temperature change are substantially the same.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above-described image display device, a plurality of optical components constituting the optical system are each fixed to the base member by an adhesive. Therefore, due to the expansion or contraction of each adhesive caused by a temperature change, displacement may occur in each optical component. When displacement occurs in the optical component, light cannot be properly guided to the two MEMS mirrors, resulting in a deterioration in the quality of the displayed image.

[0006] In view of such problems, an object of the present invention is to provide an optical block that holds a plurality of optical components in such a manner as to suppress displacement of the optical components due to temperature changes, and an image display device to which the configuration of the optical block is applied.

Means for Solving the Problems

[0007] A first aspect of the present invention relates to an optical block. The optical block according to this aspect includes a base member, a first optical component fixed to a first installation surface of the base member with a first adhesive, a second optical component fixed to a second installation surface facing the first installation surface of the base member with a second adhesive, and a third adhesive interposed between the first optical component and the second optical component, the third adhesive suppressing displacement occurring in the first optical component and the second optical component due to expansion or contraction of the first adhesive and the second adhesive caused by a temperature change by expansion or contraction due to a temperature change.

[0008] According to the optical block according to this aspect, even if the first adhesive and the second adhesive expand or contract due to a temperature change, the third adhesive interposed between the first optical component and the second optical component expands or contracts due to a temperature change, suppressing displacement of the first optical component and the second optical component in the direction in which the first installation surface and the second installation surface face each other. Therefore, displacement of the first optical component and the second optical component due to a temperature change can be suppressed.

[0009] The second aspect of the present invention relates to an image display device. The image display device according to this aspect includes a light source that emits light modulated by a video signal, at least one light deflector that two-dimensionally scans the light emitted from the light source, and the optical block according to any one of claims 1 to 6. The optical block holds optical components that impart an optical action corresponding to the scanning to the light emitted from the light source.

[0010] According to the image display device according to this aspect, since it includes the optical block according to the first aspect, displacement of the optical components due to temperature changes can be suppressed. Therefore, even when a temperature change occurs, an appropriate optical action corresponding to the scanning can be imparted to the light from the light source, and the quality of the displayed image can be maintained high.

Effects of the Invention

[0011] As described above, according to the present invention, it is possible to provide an optical block that holds a plurality of optical components in such a manner that displacement of the optical components due to temperature changes can be suppressed, and an image display device to which the configuration of the optical block is applied.

[0012] The effects or significance of the present invention will become clearer from the description of the embodiments shown below. However, the embodiments shown below are merely examples when implementing the present invention, and the present invention is not limited to those described in the following embodiments at all.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

BEST MODE FOR CARRYING OUT THE INVENTION

[0014] FIGS. 1(a) and (b) are perspective views showing the configuration of an image display device 1 according to the embodiment.

[0015] In FIGS. 1(a) and (b), X, Y, and Z axes orthogonal to each other are appended. The X-axis direction, Y-axis direction, and Z-axis direction are the front-rear direction, left-right direction, and up-down direction of the image display device 1, respectively.

[0016] The image display device 1 includes a base member 10, a light source 20, an optical system 30, a first light deflector 41, and a second light deflector 42. The base member 10 and the optical system 30 constitute an optical block 2. The base member 10 holds the light source 20, the optical system 30, the first light deflector 41, and the second light deflector 42.

[0017] The light source 20 emits light modulated by a video signal under the control of a circuit unit (not shown). The light source 20 includes, for example, three semiconductor lasers that emit light in the red wavelength band, green wavelength band, and blue wavelength band, respectively, three collimator lenses that collimate these laser lights, and an alignment optical system that aligns the optical axes of these laser lights. The alignment optical system can be constituted by, for example, two dichroic mirrors and one total reflection mirror.

[0018] However, the configuration of the light source 20 is not limited to this, and for example, a configuration that emits monochromatic parallel light modulated by a video signal may be used.

[0019] The first light deflector 41 scans the light emitted from the light source 20 in the Y-axis direction by rotating the mirror 41a (see Fig. 2(a)) about the rotation axis R1 parallel to the X-axis. The optical system 30 guides the light scanned by the first light deflector 41 to the mirror 42a of the second light deflector 42. The second light deflector 42 scans the light in a direction parallel to the X-Z plane by rotating the mirror 42a about the rotation axis R2 parallel to the Y-axis direction. Thus, by scanning the light from the light source 20 in two directions, an image for one frame is displayed.

[0020] The first light deflector 41 and the second light deflector 42 are each constituted by, for example, MEMS (Micro Electro Mechanical Systems) mirrors. For convenience, in Figs. 1(a), (b) and Fig. 2(a) and subsequent figures, the illustration of the specific configurations of the first light deflector 41 and the second light deflector 42 is omitted, and only the outer frames and the mirrors 41a, 42a are shown. The first light deflector 41 and the second light deflector 42 may be of the same type of MEMS mirror, or may be of different types of MEMS mirrors. Further, the first light deflector 41 and the second light deflector 42 may be light deflectors of types other than MEMS mirrors.

[0021] Fig. 2(a) is a diagram showing the configuration of the optical system 30.

[0022] For convenience, in Fig. 2(a), together with the optical system 30, the configurations of the light source 20, the first light deflector 41 and the second light deflector 42 are shown. Also, in Fig. 2(a), when the mirror 41a of the first light deflector 41 and the mirror 42a of the second light deflector 42 are each in the neutral position, the optical path traveled by the light emitted from the light source 20 is indicated by a dotted line.

[0023] The optical system 30 includes four mirrors 31 to 34 (optical components). The mirrors 31 and 34 have concave reflecting surfaces, and the mirrors 32 and 33 have convex reflecting surfaces. The reflecting surfaces of the mirrors 31 and 34 are cylindrical with a generatrix parallel to the X-axis, and the reflecting surfaces of the mirrors 32 and 33 are cylindrical with a generatrix parallel to the X-axis. The light reflected by the mirror 41a of the first light deflector 41 enters the reflecting surfaces of these mirrors in the order of the mirrors 31, 32, 33, and 34. The light reflected by the fourth mirror 34 enters the mirror 42a of the second light deflector 42.

[0024] When the mirror 41a of the first light deflector 41 is rotated, the light reflected by the mirror 41a is swung in the Y-axis direction. The first mirror 31 restricts the range of the swing angle of the light to the range of the reflecting surface of the second mirror 32. The second mirror 32 restricts the range of the swing angle of the light to the range of the reflecting surface of the third mirror 33. The third mirror 33 slightly expands the range of the swing angle of the light and makes the light at each swing angle enter the fourth mirror 34. The fourth mirror 34 directs the light at each swing angle toward the mirror 42a of the second light deflector 42.

[0025] The optical system 30 collects the light swung by the first light deflector 41 to the mirror 42a of the second light deflector 42 by the above actions. Thereby, the mirror 42a of the second light deflector 42 can be made smaller. Also, the optical system 30 can expand the range of the incident angle of the light when entering the mirror 42a of the second light deflector 42 by the above actions. Thereby, the angular range in the horizontal direction of the light reflected by the mirror 42a can be expanded, and a large screen can be displayed smoothly.

[0026] In the present embodiment, as shown in FIG. 2(b), a relay member 51 is disposed between the mirrors 31 and 32 arranged in the Z-axis direction, and a relay member 52 is also disposed between the mirrors 33 and 34 arranged in the Z-axis direction.

[0027] By applying an adhesive to the region A1 near the boundary between the outer surface of the relay member 51 and the outer surface of the mirror 31, the relay member 51 and the mirror 31 are integrated. Also, by applying an adhesive to the region A1 near the boundary between the outer surface of the relay member 52 and the outer surface of the mirror 33, the relay member 52 and the mirror 33 are integrated.

[0028] In this state, a gap A2 is formed between the relay member 51 and the mirror 32, and a gap A2 is also formed between the relay member 52 and the mirror 34. As will be described later, these gaps A2 are each filled with an adhesive. Thereby, the mirror 32 is connected to the relay member 51, and the mirror 34 is connected to the relay member 52.

[0029] Figure 3 is a perspective view showing the configuration of the base member 10.

[0030] The base member 10 has a rectangular box shape. The shape of the base member 10 is symmetric with respect to the Y-axis direction. The base member 10 has a rectangular recess 11 with an open top. The inner surface 12 on the positive X-axis side of the recess 11 is an inclined surface with the upper part recessed in the positive X-axis direction. Further, the recess 11 is open on the negative X-axis side by an opening 13. Below the recess 11, a gap 14 for installing the first light deflector 41 is provided, and this gap 14 is connected to the recess 11 by an opening 14a. On the upper part of the base member 10, two inclined surfaces 15 for installing the second light deflector 42 are formed.

[0031] On the positive and negative Y-axis side surfaces of the base member 10, openings 16 connected to the recess 11 are respectively formed. The opening 16 includes installation surfaces 16a, 16b facing each other in the Z-axis direction, installation surfaces 16c, 16d facing each other in the X-axis direction, and installation surfaces 16e, 16f facing each other in the X-axis direction. The mirrors 31 to 34 in Fig. 2(a) are installed with an adhesive on these mutually facing installation surfaces.

[0032] Figures 4 and 5 are cross-sectional views when the image display device in Fig. 1(a) is cut along a plane parallel to the X-Z plane at the intermediate position in the Y-axis direction.

[0033] Figures 4 and 5 show the configuration near the opening 16 on the positive Y-axis side. The configuration near the opening 16 on the negative Y-axis side is the same as that shown in Figures 4 and 5. That is, also at the opening 16 on the negative Y-axis side, in the same manner as in Figures 4 and 5, the four mirrors 31 to 34 are fixed to the installation surfaces 16a to 16f of the opening 16 by the adhesives 61 to 63, 71 to 73.

[0034] As shown in Figures 4 and 5, the mirrors 31 and 33 are fixed to the installation surface 16a (see Figure 3) of the opening 16 by the adhesive 61, and the mirrors 32 and 34 are fixed to the installation surface 16b (see Figure 3) of the opening 16 by the adhesive 62. Also, the relay member 51 and the mirror 32 are fixed by the adhesive 63, and the relay member 52 and the mirror 34 are fixed by the adhesive 53.

[0035] In the present embodiment, further, the mirrors 31 and 32 are respectively fixed to the installation surfaces 16d and 16f of the opening 16 by the adhesive 71, and the mirrors 33 and 34 are respectively fixed to the installation surfaces 16c and 16e of the opening 16 by the adhesive 72. Also, the mirrors 31 and 33 are fixed by the adhesive 73, and the mirrors 32 and 34 are fixed by the adhesive 73.

[0036] The adhesives 61 to 63, 71 to 73 are, for example, acrylic adhesives that cure by ultraviolet irradiation. Here, the same type of adhesive is used for the adhesives 61 to 63, 71 to 73. Therefore, the adhesives 61 to 63, 71 to 73 are adhesives having substantially the same expansion and contraction characteristics due to temperature changes.

[0037] During assembly, after the positions of mirrors 31 to 34 are adjusted so that the above-described optical action is imparted to light, adhesives 61 and 62 are cured by ultraviolet rays, and mirrors 31 to 34 are fixed to installation surfaces 16a and 16b. Next, as described with reference to FIG. 2(b), relay members 51 and 52 are integrated with mirrors 31 and 33 by an adhesive. Then, adhesives 63 are filled in the gaps between relay members 51 and 52 and mirrors 32 and 34, respectively, and adhesives 63 are cured by ultraviolet rays. Thereby, relay members 51 and 52 and mirrors 32 and 34 are fixed to each other.

[0038] Subsequently, adhesives 71 and 72 are filled between mirrors 31 and 33 and installation surfaces 16d and 16c, respectively, and adhesive 73 is filled between mirrors 31 and 33. Also, adhesives 71 and 72 are filled between mirrors 32 and 34 and installation surfaces 16f and 16e, respectively, and adhesive 73 is filled between mirrors 32 and 34. In this state, adhesives 71 to 73 are cured by ultraviolet rays. Thereby, mirrors 31 to 34 are fixed in the X-axis direction. Thus, the assembly of mirrors 31 to 34 constituting optical system 30 to base member 10 is completed.

[0039] Here, the thicknesses of adhesives 61 to 63 and 71 to 73 are adjusted so that the forces applied to mirrors 31 to 34 are balanced when these adhesives expand or contract due to temperature changes.

[0040] That is, as shown in FIG. 5, the thickness D13 of adhesive 63 is substantially equal to the total thickness obtained by integrating the thicknesses D11 and D12 of adhesives 61 and 62. More specifically, the thickness D11 of adhesive 61 and the thickness D12 of adhesive 62 are substantially the same, and the thickness D13 of adhesive 63 is substantially twice the thickness D11 of adhesive 61.

[0041] Thus, by adjusting the thicknesses of the adhesives 61 to 63, the forces in the negative Z-axis direction and the positive Z-axis direction applied to the mirror 31 and the mirror 32 from the adhesive 61 and the adhesive 62, respectively, due to expansion or contraction caused by temperature change (indicated by the upward arrow and the downward arrow in FIG. 5), and the forces in the positive Z-axis direction and the negative Z-axis direction applied to the mirror 31 and the mirror 32 from the adhesive 63, respectively, due to expansion or contraction caused by temperature change (indicated by the upward arrow and the downward arrow in FIG. 5) are substantially balanced. Thereby, displacement of the positions of the mirrors 31 and 32 in the Z-axis direction due to expansion or contraction of the adhesives 61 and 62 caused by temperature change is suppressed.

[0042] Similarly, displacement of the positions of the mirrors 33 and 34 in the Z-axis direction due to expansion or contraction of the adhesives 61 and 62 caused by temperature change is suppressed by the adhesive 63 interposed between these mirrors 33 and 34.

[0043] Further, the thickness D23 of the adhesive 73 is substantially equal to the total thickness obtained by integrating the thicknesses D21 and D22 of the adhesives 71 and 72. More specifically, the thickness D21 of the adhesive 71 and the thickness D22 of the adhesive 72 are substantially the same, and the thickness D23 of the adhesive 73 is substantially twice the thickness D21 of the adhesive 71.

[0044] Thus, by adjusting the thicknesses of the adhesives 71 to 73, the forces in the X-axis direction applied to the mirrors 31 and 33, respectively, due to expansion or contraction of the adhesives 71 to 73 caused by temperature change (indicated by the leftward arrow and the rightward arrow in FIG. 5) are balanced, and the forces in the X-axis direction applied to the mirrors 32 and 34 (indicated by the leftward arrow and the rightward arrow in FIG. 5) are also balanced. Therefore, displacement of the positions of these mirrors 31 to 34 in the X-axis direction due to expansion or contraction of the adhesives 71 and 72 caused by temperature change is suppressed.

[0045] Therefore, according to the configuration of the present embodiment, displacement of the mirrors 31 to 34 due to temperature change can be effectively suppressed.

[0046] <Effect of the Embodiment> According to the above embodiment, the following effects are achieved.

[0047] As shown in FIGS. 1(a), (b), 3, 4, and 5, the optical block 2 includes a base member 10, mirrors 31 and 33 (first optical components) fixed to the installation surface 16a (first installation surface) of the base member 10 with an adhesive 61 (first adhesive), mirrors 32 and 34 (second optical components) fixed to the installation surface 16b (second installation surface) facing the installation surface 16a (first installation surface) of the base member 10 with an adhesive 62 (second adhesive), and an adhesive 63 (third adhesive) interposed between the mirrors 31 and 33 (first optical components) and the mirrors 32 and 34 (second optical components), which suppresses displacement of the mirrors 31 and 33 (first optical components) and the mirrors 32 and 34 (second optical components) caused by expansion or contraction due to temperature change of the adhesive 61 (first adhesive) and the adhesive 62 (second adhesive) by expansion or contraction due to temperature change.

[0048] According to this configuration, even if the adhesives 61 and 62 expand or contract due to temperature change, the adhesive 63 interposed between the mirrors 31 and 33 and the mirrors 32 and 34 expands or contracts due to temperature change, thereby suppressing displacement of the positions of the mirrors 31 and 33 and the mirrors 32 and 34 in the direction (Z-axis direction) in which the installation surfaces 16a and 16b face each other. Therefore, displacement of the mirrors 31 and 33 and the mirrors 32 and 34 due to temperature change can be suppressed.

[0049] As described above, the adhesive 61 (first adhesive), the adhesive 62 (second adhesive), and the adhesive 63 (third adhesive) are adhesives having substantially the same expansion and contraction characteristics due to temperature change, and the thickness of the adhesive 63 (third adhesive) is substantially equal to the total thickness of the adhesive 61 (first adhesive) and the adhesive 62 (second adhesive).

[0050] According to this configuration, the force applied to the mirrors 31, 32 and the mirrors 32, 34 from the adhesives 61, 62 due to expansion or contraction caused by temperature changes can be substantially balanced with the force applied to the mirrors 31, 32 and the mirrors 32, 34 from the adhesive 63 due to expansion or contraction caused by temperature changes. Therefore, displacement of the mirrors 31, 32 and the mirrors 32, 34 due to temperature changes can be suppressed.

[0051] As described with reference to FIG. 5, the thickness D11 of the adhesive 61 (first adhesive) and the thickness D12 of the adhesive 62 (second adhesive) are substantially the same, and the thickness D13 of the adhesive 63 (third adhesive) is substantially twice the thickness of the adhesive 61 (first adhesive).

[0052] According to this configuration, by making the thicknesses of the adhesives 61 and 62 uniform, the adhesives 61 and 62 can be easily arranged with respect to the installation surfaces 16a and 16b.

[0053] As described above, the adhesive 61 (first adhesive), the adhesive 62 (second adhesive), and the adhesive 63 (third adhesive) are the same adhesive.

[0054] According to this configuration, a common adhesive can be used for the adhesives 61 to 63. Therefore, these adhesives 61 to 63 can be easily arranged in the corresponding regions.

[0055] As shown in FIGS. 4 and 5, the optical block 2 includes relay members 51 and 52 interposed between the mirrors 31, 33 (first optical components) and the mirrors 32, 34 (second optical components), and the mirrors 31, 33 (first optical components) and the mirrors 32, 34 (second optical components) are connected by the adhesive 63 (third adhesive) and the relay members 51 and 52.

[0056] According to this configuration, when there is a relatively large gap between the mirrors 31, 33 and the mirrors 32, 34 as shown in FIG. 2(a), by arranging the relay members 51 and 52, the adhesive 63 can be smoothly interposed between the mirrors 31, 33 and the mirrors 32, 34 with a predetermined thickness.

[0057] As shown in FIGS. 4 and 5, a set of mirror 31, 33 (first optical component), mirror 32, 34 (second optical component), adhesive 61 (first adhesive), adhesive 62 (second adhesive), and adhesive 63 (third adhesive) is arranged in plurality between installation surface 16a (first installation surface) and installation surface 16b (second installation surface).

[0058] According to this configuration, in each set, displacement of mirrors 31, 33 and mirrors 32, 34 due to temperature change can be suppressed.

[0059] As shown in FIGS. 3, 4, and 5, base member 10 includes installation surface 16d (third installation surface) and installation surface 16c (fourth installation surface) that sandwich a plurality of mirrors 31, 33 (first optical component) each included in a plurality of sets. Among the plurality of mirrors 31, 33 (first optical component), adhesive 71 (fourth adhesive) that fixes the mirror 31 (first optical component) closest to the installation surface 16d (third installation surface) to the installation surface 16d (third installation surface), and among the plurality of mirrors 31, 33 (first optical component), adhesive 72 (fifth adhesive) that fixes the mirror 33 (first optical component) closest to the installation surface 16c (fourth installation surface) to the installation surface 16c (fourth installation surface), and an adhesive 72 (sixth adhesive) that is interposed between adjacent mirrors 31, 33 (first optical component) and suppresses displacement generated in the plurality of mirrors 31, 33 (first optical component) due to expansion or contraction of the adhesives 71 (fourth adhesive) and 72 (fifth adhesive) due to temperature change by expansion or contraction due to temperature change.

[0060] According to this configuration, the adhesives 71 to 73 can fix the plurality of mirrors 31, 33 to the base member 10 more firmly. Further, even if the adhesives 71, 72 expand or contract due to temperature change, the adhesive 73 interposed between the adjacent mirrors 31, 33 expands or contracts due to temperature change, so that the positions of the plurality of mirrors 31, 33 are displaced in the direction (X-axis direction) in which the installation surfaces 16d, 16c face each other. Therefore, displacement of the mirrors 31, 33 due to temperature change can be suppressed.

[0061] Here, the effects of mirrors 31 and 33 are described as the first optical components. However, the same effects can be achieved when mirrors 32 and 34 are used as the first optical components.

[0062] As shown in FIGS. 1(a) and 1(b), the image display device 1 includes a light source 20 that emits light modulated by a video signal, a first light deflector 41 and a second light deflector 42 that two-dimensionally scan the light emitted from the light source 20, and an optical block 2. The optical block 2 holds optical components (mirrors 31 to 34) of an optical system 30 that imparts an optical action corresponding to the scan to the light emitted from the light source 20.

[0063] According to this configuration, since the optical block 2 shown in FIGS. 4 and 4 is provided, displacement of (mirrors 31 to 34) due to temperature change can be suppressed. Therefore, even when a temperature change occurs, an optical action corresponding to the scan can be appropriately imparted to the light from the light source 20, and the quality of the displayed image can be maintained high.

[0064] <Modification Example 1> FIG. 6 is a cross-sectional view of the image display device 1 according to Modification Example 1. The cross-sectional view of FIG. 6 is also taken at the same position as FIG. 5 when the image display device 1 is cut.

[0065] Compared with the above-described embodiment, in Modification Example 1, adhesives 71 to 73 are omitted. For this reason, in the configuration of Modification Example 1, the fixing strength of mirrors 31 to 34 to the base member 10 is slightly reduced. Therefore, in the configuration of Modification Example 1, the impact resistance is slightly reduced compared with the above-described embodiment.

[0066] However, also in the configuration of Modification Example 1, similar to the above-described embodiment, an adhesive 63 is interposed between mirrors 31 and 32, and an adhesive 63 is interposed between mirrors 33 and 34. For this reason, similar to the above-described embodiment, displacement of the positions of mirrors 31 to 34 in the Z-axis direction due to expansion or compression of adhesives 61 and 62 due to temperature change can be suppressed.

[0067] In the first modification, all the adhesives 71 to 73 are omitted from the configuration of FIG. 5, but the adhesives 71 to 73 on the positive Z-axis side may be left, or the adhesives 71 to 73 on the negative Z-axis side may be left.

[0068] <Second Modification> In the above embodiment, the plurality of optical components arranged on the base member 10 are four mirrors 31 to 34, but the number of optical components arranged on the base member 10 is not limited to this.

[0069] FIG. 7 is a cross-sectional view showing the configuration of the image display device 1 near the opening 16 according to the second modification.

[0070] For the sake of convenience, FIG. 7 schematically shows the configuration near the opening 16 on the positive Y-axis side. The cutting plane of the cross-sectional view is the same as that in the case of FIG. 5. In FIG. 7, the mirrors 31 to 36 are shown in a simplified manner, but as in the above embodiment, these mirrors 31 to 36 may be concave mirrors or convex mirrors.

[0071] In the example of FIG. 7, two sets of mirrors arranged in the Z-axis direction are arranged in three sets in the X-axis direction and installed on the base member 10. Between the mirrors 31 and 32, the relay member 51 and the adhesive 63 are interposed. Between the mirrors 33 and 34, the relay member 52 and the adhesive 63 are interposed. Between the mirrors 35 and 36, the relay member 53 and the adhesive 63 are interposed. Each set of mirrors is fixed to the installation surfaces 16a and 16b of the opening 16 by the adhesives 61 and 62. Further, the mirrors at both ends in the X-axis direction are fixed to the installation surfaces 16d, 16c and 16f, 16e of the opening 16 by the adhesives 71 and 72. Also, an adhesive 73 is interposed between the adjacent mirrors in the X-axis direction.

[0072] Also in this configuration, as in the above embodiment, the thicknesses of the adhesives 61 to 63 and 71 to 73 are adjusted so that the forces applied to the mirrors 31 to 36 are balanced when these adhesives expand or contract due to temperature changes.

[0073] That is, the thickness D13 of the adhesive 63 is substantially equal to the total thickness obtained by adding the thicknesses D11 and D12 of the adhesives 61 and 62. More specifically, the thickness D11 of the adhesive 61 and the thickness D12 of the adhesive 62 are substantially the same, and the thickness D13 of the adhesive 63 is substantially twice the thickness D11 of the adhesive 61. Thus, similar to the above-described embodiment, it is possible to suppress the displacement of the positions of the mirrors 31 to 36 in the Z-axis direction due to the expansion or contraction of the adhesives 61 and 62 caused by temperature changes.

[0074] Also, the thickness D23 of the adhesive 73 is substantially equal to the total thickness obtained by adding the thicknesses D21 and D22 of the adhesives 71 and 72. More specifically, the thickness D21 of the adhesive 71 and the thickness D22 of the adhesive 72 are substantially the same, and the thickness D23 of the adhesive 73 is substantially twice the thickness D21 of the adhesive 71.

[0075] In this way, by adjusting the thicknesses of the adhesives 71 to 73, the forces in the X-axis direction applied to the mirrors 31, 33, and 35 respectively due to the expansion or contraction of the adhesives 71 to 73 caused by temperature changes are balanced, and the forces in the X-axis direction applied to the mirrors 32, 34, and 36 are also balanced. Therefore, it is possible to suppress the displacement of the positions of these mirrors 31 to 36 in the X-axis direction due to the expansion or contraction of the adhesives 71 and 72 caused by temperature changes.

[0076] Also in the configuration of FIG. 7, similar to the above-described Modification 1, the adhesives 71 to 73 may be omitted. Further, in addition to the example shown in FIG. 7, one or four or more sets of two mirrors arranged in the Z-axis direction may be provided on the base member 10. Also in this case, the thickness of each adhesive may be adjusted in the same manner as described above.

[0077] <Other Modifications> The configurations of the image display device 1 and the optical block 2 can be variously modified other than the configurations shown in the above-described embodiment and Modifications 1 and 2.

[0078] For example, in the above embodiment, the thicknesses of the adhesives 61 and 62 were the same, but the thicknesses of the adhesives 61 and 62 may be different. Even in this case, the thickness of the adhesive 63 may be adjusted to be substantially equal to the total thickness of the adhesives 61 and 62. Thereby, a force can be generated in the adhesive 63 by the temperature change to balance the force applied to the mirror due to the expansion or contraction of the adhesives 61 and 62 caused by the temperature change. Therefore, similar to the above embodiment, displacement of the mirror in the Z-axis direction due to temperature change can be suppressed.

[0079] Similarly, the thicknesses of the adhesives 71 and 72 may be different from each other. Even in this case, the thickness of the adhesive 73 may be adjusted to be substantially equal to the total thickness of the adhesives 71 and 72.

[0080] Note that the thickness of the adhesive 63 does not necessarily have to be adjusted to the total thickness of the adhesives 61 and 62, and the thickness of the adhesive 63 may be somewhat different from the total thickness of the adhesives 61 and 62. Even in this case, compared to the case where the adhesive 63 is not interposed between the mirrors arranged in the Z-axis direction, displacement of these mirrors due to temperature change can be effectively suppressed.

[0081] Also, in the above embodiment, the same type of adhesive was used as the adhesives 61 to 63 and 71 to 73, but different types of adhesives may be used as the adhesives 61 to 63 and 71 to 73. For example, the same type of adhesive may be used for the adhesives 61 and 62, and a different type of adhesive from the adhesives 61 and 62 may be used for the adhesive 63.

[0082] In this case, the adhesives 61, 62, and the adhesive 63 may be adhesives having substantially the same expansion and contraction characteristics due to temperature change, or the adhesives 61, 62, and the adhesive 63 may be adhesives having different expansion and contraction characteristics due to temperature change.

[0083] Here, in the former case, when the adhesives 61, 62, and 63 have substantially the same expansion and contraction characteristics due to temperature changes, the thickness of the adhesive 63 is preferably adjusted to be substantially equal to the total thickness of the adhesives 61, 62. If the thicknesses of the adhesives 61, 62 are substantially the same, the thickness of the adhesive 63 is preferably adjusted to be substantially twice the thickness of the adhesives 61, 62. Thereby, similar to the above-described embodiment, displacement of the mirror in the Z-axis direction due to temperature changes can be suppressed.

[0084] Also, in the latter case, when the adhesives 61, 62, and 63 have different expansion and contraction characteristics due to temperature changes, the thickness of the adhesive 63 is preferably adjusted to a thickness that causes a force generated in the adhesive 63 due to the temperature change to balance the force applied to the mirror due to the expansion or contraction of the adhesives 61, 62 due to the temperature change. Thereby, similar to the above-described embodiment, displacement of the mirror in the Z-axis direction due to temperature changes can be suppressed.

[0085] The adhesives 61 to 63 may be adjusted in terms of material and thickness so that the forces applied to the two mirrors arranged in the Z-axis direction are balanced due to expansion or contraction caused by temperature changes. Similarly, the adhesives 71 to 73 may be adjusted in terms of material and thickness so that the forces applied to the two mirrors arranged in the X-axis direction are balanced due to expansion or contraction caused by temperature changes.

[0086] Also, in the above-described embodiment, the relay members 51, 52 are used because the gap between the two mirrors arranged in the Z-axis direction is large. However, when the gap between the two mirrors arranged in the Z-axis direction is small, the relay members 51, 52 may be omitted. Also in this case, the thicknesses of the adhesives 61 to 63 may be adjusted so that the forces applied to the two mirrors arranged in the Z-axis direction are balanced due to expansion or contraction caused by temperature changes.

[0087] In the above embodiment, the first light deflector 41 and the second light deflector 42 are separately arranged to scan light in the horizontal and vertical directions. However, one light deflector that rotates about two axes may be arranged. In this case, the two optical components arranged in the Z-axis direction may be adjusted to optical characteristics suitable for scanning by one light deflector, and the arrangement positions of these optical component sets with respect to the light deflector may be adjusted according to these optical characteristics. These optical components may be fixed to the base member 10 with an adhesive in the same manner as in the above embodiment.

[0088] In the above embodiment, the optical block used in the image display device 1 is exemplified. However, the present invention may be applied to an optical block used in a device other than the image display device 1. Further, the optical components installed in the optical block are not limited to mirrors, and may be other optical components such as lenses and diffraction gratings. The optical action imparted by the optical component to light is not limited to the optical action shown in the above embodiment.

[0089] In addition, various modifications can be appropriately made to the embodiments of the present invention within the scope of the technical idea shown in the claims.

[0090] (Supplementary Note) From the description of the above embodiments, the following technology is disclosed.

[0091] (Technology 1) A base member, A first optical component fixed to the first installation surface of the base member with a first adhesive, A second optical component fixed to the second installation surface facing the first installation surface of the base member with a second adhesive, A third adhesive interposed between the first optical component and the second optical component, which suppresses the displacement generated in the first optical component and the second optical component due to the expansion or contraction caused by the temperature change of the first adhesive and the second adhesive by the expansion or contraction due to the temperature change, An optical block characterized by the above.

[0092] According to this technique, even if the first adhesive and the second adhesive expand or contract due to a temperature change, the third adhesive interposed between the first optical component and the second optical component expands or contracts due to the temperature change, so that the positions of the first optical component and the second optical component are suppressed from being displaced in the direction in which the first installation surface and the second installation surface face each other. Therefore, displacement of the first optical component and the second optical component due to a temperature change can be suppressed.

[0093] (Technique 1) In the optical block described in Technique 1, the first adhesive, the second adhesive, and the third adhesive are adhesives having substantially the same expansion and contraction characteristics due to a temperature change, the thickness of the third adhesive is substantially equal to the total thickness of the first adhesive and the second adhesive, An optical block characterized by this.

[0094] According to this technique, the force applied to the first optical component and the second optical component from the first adhesive and the second adhesive due to expansion or contraction caused by a temperature change and the force applied to the first optical component and the second optical component from the third adhesive due to expansion or contraction caused by a temperature change can be substantially balanced. Therefore, displacement of the first optical component and the second optical component due to a temperature change can be suppressed.

[0095] (Technique 3) In the optical block described in Technique 2, the thickness of the first adhesive and the thickness of the second adhesive are substantially the same, the thickness of the third adhesive is substantially twice the thickness of the first adhesive, An optical block characterized by this.

[0096] According to this technique, by making the thicknesses of the first adhesive and the second adhesive uniform, the first adhesive and the second adhesive can be easily arranged with respect to the first installation surface and the second installation surface.

[0097] (Technique 4) In the optical block according to Technique 2 or 3, the first adhesive, the second adhesive, and the third adhesive are the same adhesive, characterized in that it is an optical block.

[0098] According to this technique, a common adhesive can be used for the first adhesive, the second adhesive, and the third adhesive. Therefore, the first adhesive, the second adhesive, and the third adhesive can be easily arranged in the corresponding regions.

[0099] (Technique 5) In the optical block according to any one of Techniques 1 to 4, a relay member interposed between the first optical component and the second optical component is provided, the first optical component and the second optical component are connected by the third adhesive and the relay member, characterized in that it is an optical block.

[0100] According to this technique, when there is a relatively large gap between the first optical component and the second optical component, by arranging the relay member, the third adhesive can be smoothly interposed between the first optical component and the second optical component.

[0101] (Technique 6) In the optical block according to any one of Techniques 1 to 5, a plurality of sets of the first optical component, the second optical component, the first adhesive, the second adhesive, and the third adhesive are arranged between the first installation surface and the second installation surface, characterized in that it is an optical block.

[0102] According to this technique, in each set, displacement of the first optical component and the second optical component due to temperature change can be suppressed.

[0103] (Technique 7) In the optical block according to Technique 6, The base member includes a third installation surface and a fourth installation surface that sandwich the plurality of first optical components respectively included in the plurality of sets. A fourth adhesive for fixing the first optical component closest to the third installation surface among the plurality of first optical components to the third installation surface, A fifth adhesive for fixing the first optical component closest to the fourth installation surface among the plurality of first optical components to the fourth installation surface, A sixth adhesive that is interposed between adjacent first optical components and suppresses displacement generated in the plurality of first optical components due to expansion or contraction caused by temperature change of the fourth adhesive and the fifth adhesive by expanding or contracting due to temperature change. An optical block characterized by the above.

[0104] According to this technique, the plurality of first optical components can be more firmly fixed to the base member by the fourth adhesive, the fifth adhesive, and the sixth adhesive. Further, even if the fourth adhesive and the fifth adhesive expand or contract due to temperature change, the sixth adhesive interposed between adjacent first optical components expands or contracts due to temperature change, so that the positions of the plurality of first optical components are displaced in the direction in which the third installation surface and the fourth installation surface face each other. This is suppressed. Therefore, displacement of the first optical component due to temperature change can be suppressed.

[0105] (Technique 8) A light source that emits light modulated by a video signal, At least one light deflector that two-dimensionally scans the light emitted from the light source, An optical block according to any one of Techniques 1 to 7, The optical block holds optical components of an optical system that imparts an optical action corresponding to scanning to the light emitted from the light source. An image display device characterized by the above.

[0106] According to this technology, since it is provided with an optical block related to any one of Technologies 1 to 7, displacement of the optical component due to temperature change can be suppressed. Therefore, even when a temperature change occurs, an optical action corresponding to scanning can be appropriately imparted to the light from the light source, and the quality of the displayed image can be maintained at a high level.

Explanation of Signs

[0107] 1 Image display device 2 Optical block 10 Base member 16a~16f Installation surface 20 Light source 30 Optical system 31~36 Mirror (optical component) 41 First light deflector 42 Second light deflector 51~53 Relay member 61~63, 71~73 Adhesive

Claims

1. A base member, a first optical component fixed to the first installation surface of the base member with a first adhesive, a second optical component fixed to the second installation surface facing the first installation surface of the base member with a second adhesive, and a third adhesive interposed between the first optical component and the second optical component, which suppresses displacement occurring in the first optical component and the second optical component due to expansion or contraction caused by temperature changes of the first adhesive and the second adhesive by expansion or contraction due to temperature changes. An optical block characterized by the above.

2. In the optical block according to Claim 1, the first adhesive, the second adhesive, and the third adhesive are adhesives having substantially the same expansion and contraction characteristics due to temperature changes, and the thickness of the third adhesive is substantially equal to the total thickness of the first adhesive and the second adhesive. An optical block characterized by the above.

3. In the optical block according to Claim 2, the thickness of the first adhesive and the thickness of the second adhesive are substantially the same, and the thickness of the third adhesive is substantially twice the thickness of the first adhesive. An optical block characterized by the above.

4. In the optical block according to Claim 2, the first adhesive, the second adhesive, and the third adhesive are the same adhesive. An optical block characterized by the above.

5. In the optical block according to Claim 1, a relay member interposed between the first optical component and the second optical component is provided, and the first optical component and the second optical component are connected by the third adhesive and the relay member. An optical block characterized by the above.

6. In the optical block according to Claim 1, a plurality of sets of the first optical component, the second optical component, the first adhesive, the second adhesive, and the third adhesive are arranged between the first installation surface and the second installation surface. An optical block characterized by the above.

7. In the optical block according to Claim 6, the base member includes a third installation surface and a fourth installation surface that sandwich a plurality of the first optical components respectively included in the plurality of sets, a fourth adhesive for fixing the first optical component closest to the third installation surface among the plurality of first optical components to the third installation surface, and a fifth adhesive for fixing the first optical component closest to the fourth installation surface among the plurality of first optical components to the fourth installation surface. A sixth adhesive that is interposed between the adjacent first optical components and suppresses displacement occurring in the plurality of first optical components due to expansion or contraction caused by temperature changes in the fourth adhesive and the fifth adhesive by expansion or contraction due to temperature changes. An optical block characterized by the above. **Claim 8** A light source that emits light modulated by a video signal. At least one light deflector that two-dimensionally scans the light emitted from the light source. An optical block according to any one of claims 1 to 7, wherein the optical block holds optical components of an optical system that imparts an optical action corresponding to scanning to the light emitted from the light source. An image display device characterized by the above. ​

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