Optical member

Abstract

The invention provides an optical member (1) which is provided with a light guide body (2) made of a light-transmitting material. The light guide body (2) is provided with an incident part (2a), an emergent part (2b) and a smooth surface (2c), wherein the incident part (2a) is incident with outdoor scene light (L1); the emergent part (2b) comprises a surface which the light incident from the incident part initially reaches and is provided with a plurality of convex prism parts (4) and a plurality of flat surfaces (3) which are alternately arranged; and the smooth surface (2c) is opposite to the emergent part and is parallel to the flat surfaces. The direction in which the emission section faces the smooth surface is referred to as X direction. The light guide further has a reinforcing portion (2Rz) protruding or recessed from the flat surface or the smooth surface in the X direction.

Description

Technical Field

[0001] The present disclosure relates to optical components. Background Art

[0002] Patent Document 1 proposes an optical component used as a blind spot auxiliary device for projecting an image in a blind spot area. The optical component includes an incident portion for incident external scene light, an exit portion formed by alternately arranging a plurality of prism portions and a plurality of flat surfaces, and a smooth surface disposed opposite to the exit portion and parallel to the flat surface. The optical component displays an image in a blind spot area by totally reflecting and guiding the light incident from the incident portion using the flat surface and the smooth surface, and emitting the light from the plurality of prism portions disposed in the exit portion.

[0003] Prior Art Literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2023-028532 Summary of the invention

[0006] However, the optical component described in Patent Document 1 may not be able to maintain parallelism between the smooth surface and the flat surface when the smooth surface changes in shape such as warping or expansion due to time-dependent changes, etc., resulting in a decrease in flatness. In this case, display distortion and parallax occur, resulting in deterioration in the aesthetics of the display. In addition, since the optical component is an integrated light guide formed of the same material or an integrated light guide formed by joining multiple materials, it is difficult to correct only the shape change of the smooth surface.

[0007] The present disclosure has been made in view of the above-mentioned points, and an object of the present disclosure is to provide an optical member capable of maintaining a smooth surface and a flat surface in parallel and preventing deterioration in the aesthetic appearance of display.

[0008] According to one aspect of the present disclosure, an optical member for guiding external scene light by internal reflection includes a light guide body made of a light-transmitting material, the light guide body including an incident portion into which the external scene light is incident, an exit portion including a surface into which the light incident from the incident portion first reaches and in which a plurality of protruding prism portions and a plurality of flat surfaces are alternately arranged, and a smooth surface opposed to the exit portion and arranged parallel to the flat surface. When the direction in which the exit portion and the smooth surface are opposed is set as the X direction, the direction in which the prism portions and the flat surfaces are alternately arranged is set as the Z direction, and the direction orthogonal to the X direction and the Z direction is set as the Y direction, the light guide body further includes a reinforcing portion that protrudes or is recessed from the flat surface or the smooth surface in the X direction and extends along the Z direction.

[0009] According to this, the light guide has a reinforcing portion, so that the rigidity is improved, and the shape change such as warping and expansion in the Z direction caused by the smooth surface and the flat surface due to the change over time can be suppressed. Therefore, the reduction in the flatness of the smooth surface and the flat surface can be suppressed, and the smooth surface and the flat surface can be kept parallel. Therefore, the optical component can prevent the deterioration of the aesthetics of the display such as distortion and parallax of the display.

[0010] In the present disclosure, “parallel” refers to a substantially parallel state, and includes a state of being completely parallel as well as a state of being substantially parallel despite slight deviations due to manufacturing tolerances and the like.

[0011] According to another aspect of the present disclosure, an optical member for guiding external scene light by internal reflection includes a light guide body made of a light-transmitting material, the light guide body having an incident portion into which the external scene light is incident, an exit portion including a surface where the light incident from the incident portion first reaches and having a plurality of protruding prism portions and a plurality of flat surfaces arranged alternately, and a smooth surface opposed to the exit portion and arranged parallel to the flat surface. When the direction in which the exit portion and the smooth surface are opposed to each other is set as the X direction, the direction in which the prism portions and the flat surfaces are arranged alternately is set as the Z direction, and the direction orthogonal to the X direction and the Z direction is set as the Y direction, the incident portion is composed of a plurality of incident prism portions extending in the Y direction and arranged in the Z direction, and the light guide body further includes a reinforcing portion protruding or recessed from the flat surface or the smooth surface in the X direction and extending in the Z direction.

[0012] Accordingly, the optical member based on another aspect of the present disclosure also achieves the same operational effects as the optical member based on one aspect of the present disclosure.

[0013] According to another aspect of the present disclosure, an optical component that guides light by reflecting external light internally includes a light guide body made of a light-transmitting material, the light guide body having an incident portion into which the external light is incident, an exit portion including a surface where the light incident from the incident portion first reaches and having a plurality of protruding prism portions and a plurality of flat surfaces arranged alternately, and a smooth surface that is opposed to the exit portion and is arranged parallel to the flat surface. When the direction in which the exit portion and the smooth surface are opposed is set to the X direction, the direction in which the prism portions and the flat surfaces are arranged alternately is set to the Z direction, and the direction orthogonal to the X direction and the Z direction is set to the Y direction, the light guide body further includes a reinforcing portion that protrudes or is recessed from the smooth surface in the X direction and extends in the Y direction. When the refractive index of the medium outside the light guide body is set to n 1 , let the refractive index of the light guide be n 2 , and the light guide angle is defined as Φ, which is the internal angle between the direction of the light incident from the incident part and the flat surface and the smooth surface and the X direction when traveling inside the light guide. 1 / n 2The enhancement portion is provided in a region on the side opposite to the incident portion in the Z direction relative to the following line, wherein the line is a line obtained by intersecting the smooth surface with an imaginary surface that passes through a position closest to the smooth surface in the prism portion arranged at a position farthest from the incident portion in the Z direction and is inclined at a light guide angle relative to the X direction.

[0014] According to this, the light guide has a reinforcing portion, so that the rigidity is improved, and the shape change such as warping and expansion in the Y direction caused by the smooth surface and the flat surface due to the change over time can be suppressed. Therefore, the reduction in the flatness of the smooth surface and the flat surface can be suppressed, and the smooth surface and the flat surface can be kept parallel. Therefore, the optical component can prevent the deterioration of the aesthetics of the display such as distortion and parallax of the display.

[0015] Furthermore, the reinforcing portion is provided in a region that does not contribute to light guiding, so that light is not captured by the reinforcing portion and light scattering does not occur, thereby preventing a decrease in display brightness. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional view for explaining light guidance in the optical member according to the first embodiment.

[0017] Figure 2 It is a side view of the optical member according to the first embodiment.

[0018] Figure 3 is from Figure 2 Rear view of the optical component observed from direction III.

[0019] Figure 4 It is a side view of the optical member of the second embodiment.

[0020] Figure 5 from Figure 4 Rear view of the optical component observed in the V direction.

[0021] Figure 6 It is a side view of the optical member of the third embodiment.

[0022] Figure 7 is from Figure 6 Rear view of the optical component observed from the VIII direction.

[0023] Figure 8 In the optical component of the fourth embodiment, Figure 3 Rear view of the part.

[0024] Fig. 9 In the optical component of the fifth embodiment, Figure 3 Rear view of the part.

[0025] Fig.10It is a side view of the optical member according to the sixth embodiment.

[0026] Fig.11 is from Fig.10 Rear view of the optical component observed in the XI direction.

[0027] Fig.12 It is a side view of the optical member of the seventh embodiment.

[0028] Fig.13 is from Fig.12 Rear view of the optical component observed from the XIII direction.

[0029] Fig.14 It is a plan view of an optical member according to an eighth embodiment.

[0030] Fig.15 is from Fig.14 Side view of the optical component observed from the XV direction.

[0031] Fig.16 is from Fig.14 and Fig.15 Rear view of the optical components observed from the XVI direction.

[0032] Fig.17 It is a side view of the optical member of the ninth embodiment.

[0033] Fig.18 is from Fig.17 Rear view of the optical component observed from the XVIII direction.

[0034] Fig.19 It is a side view of an optical member according to a tenth embodiment.

[0035] Fig. 20 is from Fig.19 Rear view of the optical component observed in the XX direction.

[0036] Fig.21 It is a plan view of an optical member according to an eleventh embodiment.

[0037] Fig. 22 is from Fig.21 Side view of the optical component observed from the XXII direction.

[0038] Fig.23 In the optical component of the twelfth embodiment, Fig. 22 Side view of the part.

[0039] Fig.24 It is a side view of an optical component according to a thirteenth embodiment.

[0040] Fig.25 is from Fig.24 Rear view of the optical component observed from the XXV direction. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals and their descriptions are omitted.

[0042] In addition, in the description of each embodiment, reference is made to Figure 1 to Figure 25 The structure of each part of the optical component 1 is simplified and described as larger than the actual structure for the convenience of description. Figure 1 , Figure 2 to Figure 25 The structure of each part of the optical component 1 is further simplified. Figure 1 This is a cross-sectional view of the optical member 1 , but hatching indicating the cross section is omitted for convenience of description.

[0043] (First Embodiment)

[0044] An optical member 1 according to a first embodiment will be described with reference to the drawings.

[0045] 〔Basic structure〕

[0046] like Figure 1 As shown, the optical component 1 of the first embodiment can be used as a blind spot assistance device, for example, which is installed on a light blocking body 100 or an obstacle that blocks the user's field of vision and creates a blind spot, and is used to enable the user to visually confirm the scene in the blind spot area.

[0047] like Figure 1 to Figure 3 As shown, the optical member 1 of the first embodiment includes a light guide 2 formed of a light-transmitting material. The light guide 2 constituting the optical member 1 has an incident portion 2a, an emitting portion 2b, a smooth surface 2c, a terminal surface 2d, and a reinforcing portion 2Rz, and can guide the external scene light L1 by reflecting it internally.

[0048] In the following, for the sake of convenience, the external light incident on the incident part 2a is referred to as "external light L1", the light incident from the incident part 2a to the inside of the light guide 2 is referred to as "incident light L2", and the light emitted from the inside of the light guide 2 to the outside is referred to as "outgoing light L3".

[0049] The incident portion 2a is a surface for the external scene light L1 to be incident inside. The exit portion 2b is formed to include a surface for the incident light L2 incident from the incident portion 2a to first arrive at, and is a structure in which a plurality of protruding prism portions 4 and a plurality of flat surfaces 3 are alternately arranged. The smooth surface 2c is a surface opposite to the exit portion 2b, and is provided parallel to the flat surface 3. The reinforcing portion 2Rz will be described later.

[0050] In the following, for the sake of convenience, the direction in which the flat surface 3 and the smooth surface 2c are opposite to each other is referred to as the "X direction". The X direction is a direction perpendicular to the flat surface 3 and the smooth surface 2c. The X direction can also be referred to as the thickness direction of the light guide 2. Sometimes, the direction from the flat surface 3 side toward the smooth surface 2c side is appropriately referred to as the +X direction, and the direction from the smooth surface 2c side toward the flat surface 3 side is appropriately referred to as the -X direction. In addition, the direction in which the plurality of prism portions 4 and the plurality of flat surfaces 3 are alternately arranged is referred to as the "Z direction". The Z direction is a direction orthogonal to the X direction. The direction from the incident portion 2a toward the terminal surface 2d, that is, the direction in which the incident light L2 incident from the incident portion 2a is guided, is appropriately referred to as the +Z direction, and the opposite direction is referred to as the -Z direction. In addition, the direction orthogonal to the X direction and the Z direction is referred to as the "Y direction". The Y direction is a direction in which the plurality of prism portions 4 and the plurality of flat surfaces 3 extend respectively.

[0051] like Figure 1 As shown, the optical component 1 has the following structure: a part of the incident light L2 incident from the incident portion 2a of the light guide 2 is reflected by the flat surface 3 of the emission portion 2b, and the light reflected by the flat surface 3 is reflected by the smooth surface 2c and is directed to the emission portion 2b side again. The optical component 1 guides the incident light L2 incident from the incident portion 2a inside the light guide 2 and emits it from the prism portion 4 of the emission portion 2b to the outside. As a result, the optical component 1 enables a user located on the emission portion 2b side to visually recognize the outside scenery of the blind spot area formed by the light shielding body 100 arranged on the smooth surface 2c side. In addition, the light shielding body 100 is set to be an object that creates a blind spot area, such as the A-pillar of a car, in the case of vehicle-mounted use, but it is not limited to this and can be appropriately changed.

[0052] The light guide 2 is a single member in a generally plate-like shape, made of a resin material such as polyethylene terephthalate, polycarbonate, polyethylene, or acrylic, or a light-transmitting material such as glass. The light guide 2 is formed, for example, by resin injection molding. The light guide 2 has the following structure: a portion of the incident light L2 is incident on the prism portion 4 of the exit portion 2b, and the rest of the incident light L2 is reflected by the flat surface 3, and the reflected light is directed toward the smooth surface 2c. Furthermore, the light guide 2 is designed to guide the incident light L2 incident from the incident portion 2a to the interior of the light guide 2 by total reflection on the smooth surface 2c and the flat surface 3. Specifically, when the refractive index of the medium (specifically, air) outside the light guide 2 is set to n 1 , the refractive index of the material constituting the light guide 2 is set to n 2 When the incident angle of the incident light L2 relative to the smooth surface 2c and the flat surface 3, i.e., the light guide angle, is set to Φ, the design satisfies the following formula (1). In detail, the light guide angle Φ refers to the internal angle between the direction in which the incident light L2 is incident on the flat surface 3 and the smooth surface 2c when traveling inside the light guide 2 and the X direction.

[0053] sinΦ>n 1 / n 2 ··· (1)

[0054] Therefore, even if the light guide 2 does not have a semi-transparent mirror or a reflective mirror made of a reflective material different from the light guide 2, a part of the incident light L2 can be repeatedly reflected between the flat surface 3 and the smooth surface 2c and emitted to the outside from the output surface 4a of the prism portion 4.

[0055] In the first embodiment, the incident portion 2a is a surface that intersects the exit portion 2b and the smooth surface 2c. The incident portion 2a is inclined toward the end surface 2d side as it moves from the exit portion 2b side toward the smooth surface 2c side. The internal angle formed by the incident portion 2a and the X direction is set to an inclination angle Ψ. The inclination angle Ψ of the incident portion 2a is smaller than the light guide angle Φ. At this time, if the angle of the external light L1 relative to the X direction is set to θ1 and the refraction condition is set to Ψ<π / 2-Φ, the incident light L2 is refracted in a direction where the light guide angle Φ is larger than the angle θ1 of the external light L1 and is guided to a larger range of the exit portion 2b. The angle θ1 can also be said to be the incident angle of the external light L1 relative to the light guide 2. The light guide 2, for example, has the following structure: Since Φ becomes the total reflection angle, the refractive index of a normal light-transmitting resin material is 1.4 or more, so according to n 2 ·sinΦ>1 gives Φ>45.3, which satisfies Φ>Ψ.

[0056] The emission portion 2b is formed adjacent to and intersecting the incident portion 2a. The emission portion 2b has a plurality of prism portions 4, which are triangular protrusions in cross-sectional view, and a plurality of flat surfaces 3. The prism portions 4 and the flat surfaces 3 are alternately arranged from the incident portion 2a toward the terminal surface 2d.

[0057] A plurality of prism portions 4 protrude from the flat surface 3 in the -X direction. The height Hp of the plurality of prism portions 4 protruding in the -X direction and the width Wp in the Z direction are of the same size. In addition, in the present disclosure, "same" means substantially the same, and in addition to being completely the same, it also includes a state that is slightly different but roughly the same due to manufacturing tolerances, etc. The plurality of prism portions 4 have an exit surface 4a that emits a portion of the incident light L2 to the outside and another surface 4b adjacent to the exit surface 4a. The exit surface 4a of the plurality of prism portions 4 is a surface parallel to the incident portion 2a, and the inclination angle relative to the X direction is set to Ψ. As a result, the light of the incident light L2 that reaches the exit surface 4a is emitted to the outside as the exit light L3 at the same angle θ2 as the external scene light L1. Therefore, the continuity between the external scene that does not pass through the optical component 1 when observed by the user on the side of the exit portion 2b and the external scene in the blind area that can be visually confirmed by the optical component 1 (i.e., the display based on the optical component 1) is ensured. Among the plurality of prism portions 4 , for example, the interval between the prism portions 4 adjacent to each other in the Z direction (that is, the width Ws of the flat surface 3 in the Z direction) is constant.

[0058] The plurality of flat surfaces 3 are opposite to the smooth surface 2c and are formed parallel to the smooth surface 2c. In the present disclosure, "parallel" refers to a substantially parallel state, and includes a state in which the plane is substantially parallel despite slight deviations due to manufacturing tolerances, etc. The plurality of flat surfaces 3 are arranged on the same plane. With respect to the plurality of flat surfaces 3, since the incident light L2 from the incident portion 2a is incident at an angle greater than the critical angle, the plurality of flat surfaces 3 function as a reflection surface that reflects the incident light L2 toward the smooth surface 2c side by total reflection.

[0059] The end face 2d is a face connecting the emission part 2b and the smooth face 2c. The inclination of the end face 2d is arbitrary. In addition, the side faces 2f located at both ends of the light guide 2 in the Y direction and connecting the incident part 2a, the emission part 2b, the smooth face 2c and the end face 2d are faces that do not contribute optically, and the shape, structure, etc. are arbitrary. The above is the basic structure of the optical component 1.

[0060] [Reinforcement section 2Rz]

[0061] Next, refer to Figure 2 and Figure 3 Next, the reinforcing portion 2Rz will be described.

[0062] When the smooth surface 2c of the light guide 2 constituting the optical member 1 changes in shape such as warping or expansion due to time-dependent changes, and the flatness is reduced, the smooth surface 2c may not be kept parallel to the flat surface 3. In this case, display distortion and parallax occur, resulting in deterioration of the aesthetics of the display.

[0063] Therefore, the optical component 1 has a reinforcing portion 2Rz at a portion on the side of the smooth surface 2c of the light guide 2. In the first embodiment, the reinforcing portion 2Rz is a convex portion that protrudes from the smooth surface 2c in the +X direction and extends along the Z direction. In addition, the reinforcing portion 2Rz is provided at both ends in the Y direction of the smooth surface 2c. The reinforcing portion 2Rz is, for example, quadrilateral in cross-sectional observation in the XY plane (in other words, in cross-sectional observation perpendicular to the Z direction).

[0064] In the first embodiment, the reinforcing portion 2Rz is formed of the same material as the light-transmitting material constituting the light guide 2. The reinforcing portion 2Rz can be formed integrally and continuously with the light guide 2 by, for example, resin injection molding. In addition, without limitation thereto, as described in (1) of "other embodiments" described later, the reinforcing portion 2Rz can also be formed of a material different from the light-transmitting material constituting the light guide 2, and be provided as a structure joined to the light guide 2.

[0065] The reinforcing portion 2Rz of the first embodiment functions like a beam with respect to the light guide 2, and can improve the rigidity of the light guide 2. The reinforcing portion 2Rz suppresses the smooth surface 2c and the flat surface 3 from changing in shape such as warping and expansion in the X direction due to time changes in the Z direction. Therefore, it is possible to suppress the reduction in the flatness of the smooth surface 2c and the flat surface 3, and keep the smooth surface 2c and the flat surface 3 parallel. Therefore, the optical component 1 can prevent the deterioration of the aesthetics of the display, such as distortion and parallax of the display.

[0066] (Second to Eighth Embodiments)

[0067] The second to eighth embodiments are different from the first embodiment in that the structure of the reinforcement portion 2Rz is changed, and the other parts are the same as the first embodiment, so only the parts different from the first embodiment will be described.

[0068] (Second Embodiment)

[0069] The second embodiment is described. Figure 4 and Figure 5 As shown in FIG. 1 , the reinforcing portion 2Rz of the optical member 1 of the second embodiment is formed in a groove shape that is recessed from the smooth surface 2c in the -X direction and extends in the Z direction, that is, in a concave shape. The reinforcing portion 2Rz is provided at a position that is closer to the inside than the two side surfaces 2f in the Y direction of the light guide 2. The reinforcing portion 2Rz is formed integrally with the light guide 2, for example, by resin injection molding. That is, the reinforcing portion 2Rz is formed of the same material as the light-transmitting material constituting the light guide 2.

[0070] The reinforcing portion 2Rz of the second embodiment improves the rigidity of the light guide 2 by utilizing its concave shape, thereby suppressing the smooth surface 2c and the flat surface 3 from changing in shape such as warping and expansion in the X direction in the Z direction due to changes over time. Therefore, it is possible to suppress the reduction in the flatness of the smooth surface 2c and the flat surface 3, thereby maintaining the smooth surface 2c and the flat surface 3 parallel. Therefore, the optical member 1 can prevent the deterioration of the aesthetics of the display.

[0071] (Third Embodiment)

[0072] like Figure 6 and Figure 7 As shown, the optical component 1 of the third embodiment has a reinforcing portion 2Rz on the side of the emission portion 2b of the light guide 2. The reinforcing portion 2Rz of the third embodiment protrudes from the flat surface 3 of the emission portion 2b in the -X direction and extends along the Z direction. In addition, the reinforcing portion 2Rz is arranged on the outside of the prism portion 4 of the emission portion 2b in the Y direction and is connected to the prism portion 4. The reinforcing portion 2Rz is formed integrally with the light guide 2, for example, by resin injection molding. That is, the reinforcing portion 2Rz is formed of the same material as the light-transmitting material constituting the light guide 2.

[0073] The reinforcing portion 2Rz of the third embodiment functions like a beam with respect to the light guide 2, and can improve the rigidity of the light guide 2. The reinforcing portion 2Rz suppresses the smooth surface 2c and the flat surface 3 from changing in shape such as warping and expansion in the X direction due to time changes in the Z direction. Therefore, it is possible to suppress the reduction in the flatness of the smooth surface 2c and the flat surface 3, and keep the smooth surface 2c and the flat surface 3 parallel. Therefore, the optical component 1 can prevent the deterioration of the aesthetics of the display, such as distortion and parallax of the display.

[0074] (Fourth Embodiment)

[0075] The fourth embodiment is a modified example of the first embodiment. Figure 8 As shown, the optical component 1 of the fourth embodiment has a reinforcing portion 2Rz protruding from the smooth surface 2c in the +X direction and extending along the Z direction. The reinforcing portion 2Rz is triangular in cross-sectional observation of the XY plane (in other words, in cross-sectional observation perpendicular to the Z direction). The reinforcing portion 2Rz of the fourth embodiment also has the same effect as the first embodiment.

[0076] (Fifth Embodiment)

[0077] The fifth embodiment is also a modified example of the first embodiment. Fig. 9As shown, the optical component 1 of the fifth embodiment also has a reinforcing portion 2Rz that protrudes from the smooth surface 2c in the +X direction and extends along the Z direction. The surface of the reinforcing portion 2Rz facing the +X direction is a curved surface shape that is convex in the +X direction when viewed in a cross-section in the XY plane (in other words, when viewed in a cross-section perpendicular to the Z direction). The reinforcing portion 2Rz of the fifth embodiment also has the same effects as those of the first embodiment.

[0078] (Sixth Embodiment)

[0079] The sixth embodiment is described. Fig.10 and Fig.11 As shown, the optical component 1 of the sixth embodiment also has a reinforcing portion 2Rz protruding from the smooth surface 2c in the +X direction and extending along the Z direction. In the sixth embodiment, the width Wy of the light guide 2 in the Y direction is larger than the width Wpy of the prism portion 4 of the emission portion 2b in the Y direction. In addition, the reinforcing portion 2Rz of the sixth embodiment is provided at a position on the side of the smooth surface 2c of the light guide 2 at a position closer to the outside in the Y direction than the prism portion 4 of the emission portion 2b.

[0080] Among them, if it is assumed that the enhancement part 2Rz is set at a position opposite to the prism part 4 in the X direction, when the incident light L2 is reflected by the flat surface 3 and the smooth surface 2c and guided in the Z direction, the light will be captured by the enhancement part 2Rz and light scattering will occur, resulting in a phenomenon of reduced brightness of the display.

[0081] In contrast, in the sixth embodiment, the reinforcing portion 2Rz is disposed outside the prism portion 4 in the Y direction. Thus, when the incident light L2 is reflected by the flat surface 3 and the smooth surface 2c and guided along the Z direction, the light is not captured by the reinforcing portion 2Rz and light scattering does not occur, thereby preventing a decrease in the brightness of the display.

[0082] (Seventh Embodiment)

[0083] The seventh embodiment is described. Fig.12 and Fig.13 As shown, in the seventh embodiment, the reinforcing portion 2Ry is provided at a portion on the side of the end surface 2d on the side of the smooth surface 2c of the light guide 2. The reinforcing portion 2Ry protrudes from the smooth surface 2c in the +X direction and extends along the Y direction. In the following description, the reinforcing portion 2Rz extending along the Z direction described in the first to sixth embodiments is sometimes referred to as the "first reinforcing portion 2Rz", and the reinforcing portion 2Ry extending along the Y direction to be described in the seventh embodiment is sometimes referred to as the "second reinforcing portion 2Ry".

[0084] exist Fig.12 and Fig.13In FIG. 1 , the region where the second reinforcement portion 2Ry can be provided is indicated by arrows S1 and S2 . The region is defined as follows.

[0085] first, Fig.12 The double-dashed line DL represents the following imaginary surface, which passes through the position 4c closest to the smooth surface 2c in the prism portion 4 arranged at the position farthest from the incident portion 2a in the Z direction and is inclined at a light guide angle Φ relative to the X direction. In addition, the light guide angle Φ is calculated according to the following formula (2).

[0086] arcsin(n 1 / n 2 )=Φ ··· (2)

[0087] n 1 is the refractive index of the medium (specifically, air) outside the light guide 2, n 2 is the refractive index of the light guide 2.

[0088] then, Fig.12 ξ represents the line obtained by the intersection of the virtual surface indicated by the double-dashed line DL and the smooth surface 2c. The area closer to the +Z direction than the line ξ (i.e., the area closer to the end surface 2d than the line ξ) is the area defined by arrows S1 and S2. This area is an area that does not contribute to the light guiding on the smooth surface 2c. The second reinforcing portion 2Ry is provided in this area.

[0089] The second reinforcing portion 2Ry of the optical member 1 of the seventh embodiment extends in the Y direction, thereby preventing the smooth surface 2c and the flat surface 3 from changing in shape such as warping or expansion in the X direction due to time-dependent changes in the Y direction. Therefore, it is possible to prevent the flatness of the smooth surface 2c and the flat surface 3 from decreasing, thereby maintaining the smooth surface 2c and the flat surface 3 parallel to each other.

[0090] Furthermore, the second reinforcing portion 2Ry of the optical member 1 of the seventh embodiment is provided in the region defined by the arrows S1 and S2. This region does not contribute to the light guiding. Therefore, light is not captured by the second reinforcing portion 2Ry, and light scattering does not occur, thereby preventing a decrease in display brightness.

[0091] (Eighth Embodiment)

[0092] like Figure 14 to Figure 16 As shown, the optical member 1 of the eighth embodiment includes the first reinforcing portion 2Rz described in the sixth embodiment and the second reinforcing portion 2Ry described in the seventh embodiment. The end of the first reinforcing portion 2Rz on the distal end surface 2d side is continuously formed with both ends of the second reinforcing portion 2Ry in the Y direction.

[0093] The optical member 1 of the eighth embodiment can suppress the smooth surface 2c and the flat surface 3 from changing in shape such as warping or expansion in the X direction in the Z direction and the Y direction by the first reinforcing portion 2Rz and the second reinforcing portion 2Ry.

[0094] Furthermore, in the eighth embodiment, the first reinforcing portion 2Rz is disposed outside the prism portion 4 in the Y direction, and the second reinforcing portion 2Ry is disposed in the region defined by arrows S1 and S2. Thus, light is not captured by the first reinforcing portion 2Rz and the second reinforcing portion 2Ry, and light scattering does not occur, thereby preventing a decrease in display brightness.

[0095] (Ninth and Tenth Embodiments)

[0096] The ninth and tenth embodiments are different from the first embodiment and the like in that they include a light absorbing portion and are otherwise the same as the first embodiment and the like, and therefore only the differences from the first embodiment and the like will be described.

[0097] (Ninth Embodiment)

[0098] like Fig.17 and Fig.18 As shown, the reinforcing portion 2Rz provided in the optical component 1 of the ninth embodiment is the same as the reinforcing portion described in the sixth embodiment. In addition, the optical component 1 of the ninth embodiment includes a light absorbing portion 5 covering the reinforcing portion 2Rz. The light absorbing portion 5 is composed of, for example, a black sheet or a black coating that absorbs light. The light absorbing portion 5 is provided on at least a corner portion of the reinforcing portion 2Rz. Specifically, the light absorbing portion 5 is provided on a surface facing the +X direction and a surface facing the inner side in the Y direction in the reinforcing portion 2Rz. In addition, on the side surface 2f facing the outer side in the Y direction in the light guide 2, when a bracket not shown in the figure is provided, the light absorbing portion 5 is not required.

[0099] Among them, when the light absorption part 5 is not set at the corner of the reinforcing part 2Rz, when the incident light L2 is reflected by the flat surface 3 and the smooth surface 2c and guided in the Z direction, there is a concern that the light will reach the corner of the reinforcing part 2Rz and scatter, thereby causing the aesthetics of the display to deteriorate.

[0100] In contrast, the optical member 1 of the ninth embodiment includes the light absorbing portion 5 covering at least the corner of the reinforcing portion 2Rz, so that the light reaching the corner of the reinforcing portion 2Rz is absorbed by the light absorbing portion 5. Therefore, the optical member 1 can prevent light scattering caused by light reaching the corner of the reinforcing portion 2Rz, thereby preventing deterioration in the aesthetics of the display.

[0101] (Tenth Embodiment)

[0102] like Fig.19 and Fig. 20As shown in FIG. 1 , the reinforcing portion 2Rz included in the optical member 1 of the tenth embodiment is formed in a groove shape that is recessed from the smooth surface 2c in the -X direction and extends in the Z direction, that is, a concave shape. The reinforcing portion 2Rz is provided on the smooth surface 2c at a position that is closer to the outside in the Y direction than the prism portion 4 included in the emission portion 2b. The optical member 1 of the tenth embodiment also includes a light absorbing portion 5 that covers the corner of the reinforcing portion 2Rz. The light absorbing portion 5 is provided in a manner that covers the inner surface of the concave reinforcing portion 2Rz including the corner.

[0103] The optical member 1 of the tenth embodiment includes the light absorbing portion 5 covering the inner surface including the corner of the concave reinforcing portion 2Rz, thereby preventing light scattering caused by light reaching the reinforcing portion 2Rz and preventing degradation of the display aesthetics.

[0104] (Eleventh and Twelfth Embodiments)

[0105] The eleventh and twelfth embodiments differ from the first embodiment in that the incident portion 2a is composed of a plurality of incident prism portions 6, and the rest is the same as the first embodiment. Therefore, only the differences from the first embodiment will be described.

[0106] (Eleventh Embodiment)

[0107] like Fig.21 and Fig. 22 As shown, the incident portion 2a of the optical component 1 of the eleventh embodiment is composed of a plurality of incident prism portions 6. The plurality of incident prism portions 6 protrude from the smooth surface 2c in the +X direction. The plurality of incident prism portions 6 extend respectively along the Y direction and are arranged in the Z direction. The joints between the plurality of incident prism portions 6 (i.e., the valleys of the plurality of incident prism portions 6) are arranged on the same plane as the smooth surface 2c. In the following description, the surface of the plurality of incident prism portions 6 facing the side opposite to the end surface 2d is referred to as the "prism incident surface 6a", and the surface facing the end surface 2d side is referred to as the "prism other surface 6b". The inclination angle Ψ of the prism incident surface 6a is the same as the inclination angle Ψ of the incident portion 2a described in the first embodiment.

[0108] The optical member 1 of the eleventh embodiment has the following structure: a part of the incident light L2 incident from the plurality of prism incident surfaces 6a to the inside of the light guide 2 is reflected by the flat surface 3 of the emission portion 2b, and the light reflected by the flat surface 3 is reflected by the smooth surface 2c and is directed toward the emission portion 2b side again. The optical member 1 guides the incident light L2 incident from the plurality of prism incident surfaces 6a inside the light guide 2 and emits it from the prism portion 4 of the emission portion 2b to the outside. Thus, the optical member 1 enables a user located on the emission portion 2b side to visually recognize the outside view of the blind spot area formed by the light shielding body 100 disposed on the smooth surface 2c side.

[0109] The optical member 1 of the eleventh embodiment includes a first reinforcing portion 2Rz and a second reinforcing portion 2Ry. The first reinforcing portion 2Rz is disposed outside the plurality of incident prism portions 6 in the Y direction. The end portion on the terminal surface 2d side of the first reinforcing portion 2Rz is formed continuously with both ends in the Y direction of the second reinforcing portion 2Ry. In addition, the first reinforcing portion 2Rz is disposed outside the prism portion 4 constituting the emission portion 2b in the Y direction.

[0110] The optical member 1 of the eleventh embodiment can suppress the smooth surface 2c and the flat surface 3 from changing in shape such as warping or expansion in the X direction in the Z direction and the Y direction by the first reinforcing portion 2Rz and the second reinforcing portion 2Ry.

[0111] Furthermore, in the eleventh embodiment, the first reinforcing portion 2Rz is disposed outside the plurality of incident prism portions 6 in the Y direction, and is disposed outside the plurality of prism portions 4 constituting the emission portion 2b in the Y direction. The second reinforcing portion 2Ry is disposed in the region defined by arrows S1 and S2. Thus, light guided in the light guide 2 is not captured by the first reinforcing portion 2Rz and the second reinforcing portion 2Ry, and light scattering is not generated, thereby preventing a reduction in display brightness.

[0112] (Twelfth Embodiment)

[0113] The twelfth embodiment is different from the eleventh embodiment in that the heights of the first reinforcement portion 2Rz and the second reinforcement portion 2Ry in the X direction are changed. The other parts are the same as the eleventh embodiment, and therefore only the differences from the eleventh embodiment will be described.

[0114] like Fig.23 As shown, in the eleventh embodiment, the height of the first reinforcing portion 2Rz and the second reinforcing portion 2Ry in the X direction is set to H, the distance between the flat portion and the smooth surface 2c is set to Hw, and the height of the plurality of incident prism portions 6 in the X direction is set to h. At this time, the following relationship is established between equations (3) and (4).

[0115] H≤3Hw ··· (3)

[0116] H>h ··· (4)

[0117] According to the above formula (3), the height H of the first reinforcing portion 2Rz and the second reinforcing portion 2Ry in the X direction is set to be less than or equal to 3 times the distance Hw between the flat portion and the smooth surface 2c. Thus, when the light guide 2 is formed by resin injection molding, it is possible to suppress the mixing of bubbles into the first reinforcing portion 2Rz and the second reinforcing portion 2Ry, and it is possible to suppress the occurrence of poor demolding from the injection molding mold in the first reinforcing portion 2Rz and the second reinforcing portion 2Ry.

[0118] In addition, according to the above formula (4), when the light guide 2 is housed in a bracket (not shown), it is possible to prevent the vertices of the plurality of incident prism portions 6 from interfering with the inner side surface of the bracket and causing damage to the plurality of incident prism portions 6. In addition, although not limiting the present disclosure, it is preferable to set Hw = 10 (mm), h = 1 (mm), and H = 0.1 + h (mm), for example.

[0119] (Thirteenth embodiment)

[0120] The thirteenth embodiment is different from the sixth embodiment in that the number of reinforcing portions 2Rz is changed and the rest is the same as the sixth embodiment, so only the differences from the sixth embodiment will be described.

[0121] like Fig.24 and Fig.25 As shown in FIG. 13 , the optical member 1 of the thirteenth embodiment has a plurality of reinforcing portions 2Rz that protrude from the smooth surface 2c in the +X direction and extend in the Z direction. Fig.25 As shown, two reinforcing parts 2Rz are provided at one end of the smooth surface 2c in the Y direction, and two reinforcing parts 2Rz are provided at the other end of the smooth surface 2c in the Y direction. The plurality of reinforcing parts 2Rz are provided on the smooth surface 2c at a position closer to the outside of the prism part 4 of the emission part 2b in the Y direction.

[0122] In the thirteenth embodiment, the width of the light guide 2 in the Y direction is larger than the width of the prism portion 4 of the emission portion 2b in the Y direction. Therefore, a step surface 7 is provided on the outer side of the prism portion 4 of the emission portion 2b in the Y direction. The plurality of reinforcing portions 2Rz are provided on the smooth surface 2c side of the light guide 2 at a position opposite to the step surface 7 in the X direction.

[0123] However, when the light guide 2 is formed by resin injection molding, if the volume of the reinforcing portion 2Rz is increased, there is a concern that a molding defect called a sink mark may occur on the step surface 7 .

[0124] In contrast, in the thirteenth embodiment, the reinforcing portion 2Rz on one side in the Y direction is formed of a plurality of pieces, and the reinforcing portion 2Rz on the other side in the Y direction is also formed of a plurality of pieces. Thus, when the light guide 2 is formed by resin injection molding, molding defects of the step surface 7 can be alleviated.

[0125] (Other embodiments)

[0126] (1) In the above-mentioned embodiments, the scheme in which the reinforcing parts 2Rz and 2Ry are formed of the same material as the translucent material constituting the light guide 2 is described, but it is not limited to this. For example, the reinforcing parts 2Rz and 2Ry may be formed of a material different from the translucent material constituting the light guide 2, and be provided with a structure joined to the light guide 2. In this case, as the material of the reinforcing parts 2Rz and 2Ry, for example, metals such as aluminum, resins such as polypropylene, rubber, etc. can be used. In addition, the rubber is preferably hard rubber. Thus, the reinforcing parts 2Rz and 2Ry can be added to the light guide 2 to suppress the reduction in the flatness of the smooth surface 2c and the flat surface 3, and the smooth surface 2c and the flat surface 3 can be kept parallel. Therefore, the optical component 1 can prevent the deterioration of the aesthetics of the display, such as distortion and parallax of the display.

[0127] (2) In the first, fourth, and fifth embodiments, the cross-sectional shape of the reinforcement portion 2Rz is exemplified by a quadrangular shape, a triangular shape, and a curved shape. However, the reinforcement portions 2Rz and 2Ry are not limited thereto and may have any shape.

[0128] (3) In the seventh and eighth embodiments, the second reinforcement portion 2Ry is described as being convex and protruding from the smooth surface 2c in the +X direction. However, the present invention is not limited thereto and the second reinforcement portion 2Ry may be concave and recessed from the smooth surface 2c in the -X direction.

[0129] (4) In the above-mentioned thirteenth embodiment, the reinforcement portion arranged on one side in the Y direction in the first reinforcement portion 2Rz is composed of multiple roots, and the reinforcement portion arranged on the other side in the Y direction is also composed of multiple roots, but it is not limited to this. For example, the second reinforcement portion 2Ry can also be composed of multiple roots.

[0130] The present disclosure is not limited to the above-mentioned embodiments, and can be appropriately changed within the scope described in the claims. In addition, the above-mentioned embodiments and a part thereof are not embodiments that have nothing to do with each other, and can be appropriately combined except for the case that is obviously not combinable. In addition, in the above-mentioned embodiments, the elements constituting the embodiments are not necessarily necessary elements, except for the cases that are specifically stated as necessary and the cases that are clearly considered to be necessary in principle. In addition, in the above-mentioned embodiments, when referring to the number, value, amount, range and other numerical values ​​of the constituent elements of the embodiments, except for the cases that are specifically stated as necessary and the cases that are clearly limited to a specific number in principle, it is not limited to the specific number. In addition, in the above-mentioned embodiments, when referring to the shape, positional relationship, etc. of the constituent elements, etc., except for the cases that are specifically stated and the cases that are limited to a specific shape, positional relationship, etc. in principle, it is not limited to the shape, positional relationship, etc.

Claims

1. An optical member that guides light by reflecting external scene light internally, characterized in that: The optical member includes a light guide body made of a light-transmitting material, the light guide body having an incident portion into which the external scene light is incident, an exit portion including a surface into which the light incident from the incident portion first reaches and having a plurality of protruding prism portions and a plurality of flat surfaces alternately arranged, and a smooth surface opposed to the exit portion and provided parallel to the flat surface. When the direction in which the emission portion and the smooth surface face each other is defined as the X direction, the direction in which the prism portions and the flat surfaces are alternately arranged is defined as the Z direction, and the direction orthogonal to the X direction and the Z direction is defined as the Y direction, The light guide further includes a reinforcing portion that protrudes or is recessed from the flat surface or the smooth surface in the X direction and extends along the Z direction.

2. An optical member that guides light by reflecting external scene light internally, characterized in that: The optical member includes a light guide body made of a light-transmitting material, the light guide body having an incident portion into which the external scene light is incident, an exit portion including a surface into which the light incident from the incident portion first reaches and having a plurality of protruding prism portions and a plurality of flat surfaces alternately arranged, and a smooth surface opposed to the exit portion and provided parallel to the flat surface. When the direction in which the emission portion and the smooth surface face each other is defined as the X direction, the direction in which the prism portions and the flat surfaces are alternately arranged is defined as the Z direction, and the direction orthogonal to the X direction and the Z direction is defined as the Y direction, The incident portion is composed of a plurality of incident prism portions extending along the Y direction and arranged in the Z direction, The light guide further includes a reinforcing portion that protrudes or is recessed from the flat surface or the smooth surface in the X direction and extends along the Z direction.

3. The optical component according to claim 2, wherein: The reinforcement portion is a structure protruding from the smooth surface in the X direction. When the height of the reinforcing portion in the X direction is H, and the distance between the vertices of the plurality of incident prism portions and the smooth surface in the X direction is h, There is a relationship of H>h.

4. The optical component according to claim 1 or 2, characterized in that: The reinforcing portion is provided on the light guide at an outer side in the Y direction than the prism portion.

5. The optical component according to claim 1 or 2, characterized in that: When the reinforcing portion is referred to as a first reinforcing portion, The light guide further includes a second reinforcing portion that protrudes or is recessed from the smooth surface in the X direction and extends along the Y direction. When the refractive index of the medium outside the light guide is n1, the refractive index of the light guide is n2, and the internal angle formed by the direction of the light incident from the incident portion toward the flat surface and the smooth surface and the X direction when traveling inside the light guide, i.e., the light guide angle is Φ, The light guide angle is calculated using arcsin(n1 / n2)=Φ, The second enhancement portion is arranged in an area on the side opposite to the incident portion in the Z direction relative to the following line, wherein the line is a line obtained by intersecting the smooth surface with an imaginary surface that passes through the position closest to the smooth surface in the prism portion arranged at the position farthest from the incident portion in the Z direction and is inclined at the light guiding angle relative to the X direction.

6. The optical component according to claim 1 or 2, characterized in that: The reinforcement portion is a structure protruding from the smooth surface in the X direction. When the height of the reinforcing portion in the X direction is H and the distance between the flat surface and the smooth surface is Hw, It has the relationship of H≤3×Hw.

7. The optical component according to claim 1 or 2, characterized in that: The optical member further includes a light absorbing portion covering a corner portion of the reinforcing portion.

8. The optical component according to claim 1 or 2, characterized in that: The reinforcing portion is formed continuously with the light guide body from the same material as the light-transmitting material constituting the light guide body.

9. The optical component according to claim 1 or 2, characterized in that: The reinforcing portion is a structure protruding from the flat surface or the smooth surface in the X direction. The reinforcing portion is formed of a material different from a light-transmitting material constituting the light guide and is bonded to the light guide.

10. The optical component according to claim 1 or 2, characterized in that: Among the reinforcing portions, a plurality of the reinforcing portions are provided on one side in the Y direction, and a plurality of the reinforcing portions are provided on the other side in the Y direction.

11. An optical member that guides light by reflecting external scene light internally, characterized in that: The optical member includes a light guide body made of a light-transmitting material, the light guide body having an incident portion into which the external scene light is incident, an exit portion including a surface into which the light incident from the incident portion first reaches and having a plurality of protruding prism portions and a plurality of flat surfaces alternately arranged, and a smooth surface opposed to the exit portion and provided parallel to the flat surface. When the direction in which the emission portion and the smooth surface face each other is defined as the X direction, the direction in which the prism portions and the flat surfaces are alternately arranged is defined as the Z direction, and the direction orthogonal to the X direction and the Z direction is defined as the Y direction, The light guide further comprises a reinforcing portion protruding or recessed from the smooth surface in the X direction and extending in the Y direction. When the refractive index of the medium outside the light guide is n1, the refractive index of the light guide is n2, and the internal angle formed by the direction of the light incident from the incident portion toward the flat surface and the smooth surface and the X direction when traveling inside the light guide, i.e., the light guide angle is Φ, The light guide angle is calculated using arcsin(n1 / n2)=Φ, The enhancement portion is arranged in an area on the side opposite to the incident portion in the Z direction relative to the following line, wherein the line is a line obtained by intersecting the smooth surface with an imaginary surface that passes through a position closest to the smooth surface in the prism portion arranged at a position farthest from the incident portion in the Z direction and is inclined at the light guiding angle relative to the X direction.

12. The optical component according to claim 11, wherein The incident portion is composed of a plurality of incident prism portions extending along the Y direction and arranged in the Z direction.

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