Lens, inner lens, and light-emitting device

Abstract

To provide a lens capable of guiding light from a light source to a wider range, an inner lens, and a light emitting device.SOLUTION: The lens 23 guides light emitted from the light emitting element 21. The lens 23 includes the condensing portion 30 that faces the light emitting element 21, extends in a direction facing the light emitting element 21, and has the axis J passing through the light emitting element 21, the reflection surface 37,38 that reflects the light condensed by the condensing portion 30, and the emission surface 39 that emits the light reflected by the reflection surface 37,38. The reflection surface 37,38 has an arc shape centered on the axis J in a cross-sectional view when cut along a plane orthogonal to the axis J, and the distance from the axis J becomes shorter or longer as it goes away from the condensing portion 30 in the direction in which the axis J extends.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a lens, an inner lens, and a light-emitting device. [Background technology]

[0002] A known example of a conventional light-emitting device is the display device shown in Patent Document 1. This display device includes a housing having a recess inside a peripheral wall surrounding an opening, a light source disposed on the outer periphery of the recess, and a lid whose end is joined to the top surface of the peripheral wall so as to close the opening of the housing.

[0003] A light-transmitting decorative surface is formed on the surface of the lid facing the housing. A light guide plate that guides light from the light source toward the center of the housing is located inside the housing closer to the lid than the light source. The light from the light source is reflected by the inclined surface (reflective surface) of the light guide plate, then passes through the lid and is emitted to the outside, causing the lid to emit light. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-224414 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the display device described above, the inclined surface of the light guide plate is flat. Therefore, the inclined surface can only reflect the light from the light source in one direction. Therefore, there is room for improvement in reflecting the light from the light source in a wider range of directions. [Means for solving the problem]

[0006] Below, various aspects of a lens, an inner lens, and a light emitting device for solving the above problems will be described. [Embodiment 1] A lens that guides light emitted from a light source, comprising: a focusing section that faces the light source and extends in a direction facing the light source and has an axis that passes through the light source; a reflective surface that reflects the light focused by the focusing section; and an exit surface that emits the light reflected by the reflective surface, wherein the reflective surface has an arc shape centered on the axis in a cross-sectional view when cut with a plane perpendicular to the axis, and the distance from the axis becomes shorter or longer as it moves away from the focusing section in the direction in which the axis extends.

[0007] According to the above configuration, the reflecting surface is an arc-shaped curved surface centered on the axis of the light collecting portion, so that light can be reflected in a wider range of directions than if the reflecting surface were flat, and therefore the light from the light source can be guided over a wider range.

[0008] [Aspect 2] The lens according to [Aspect 1], wherein the reflecting surface is a curved surface forming the side surface of a semi-cone. According to the above configuration, the reflective surface can reflect light in directions within a range of 180°.

[0009] [Aspect 3] A lens described in [Aspect 1] or [Aspect 2], characterized in that the exit surface has an arc shape centered on the axis when viewed in cross section when cut on a plane perpendicular to the axis, and the distance from the axis becomes shorter as the exit surface moves away from the focusing section in the direction in which the axis extends.

[0010] According to the above configuration, the exit surface is an arc-shaped curved surface centered on the axis of the light collecting portion, so the exit surface can be made smaller than when the exit surface is flat. [Aspect 4] The lens according to any one of [Aspect 1] to [Aspect 3], wherein the light exit surface is a curved surface forming the side surface of a semicircular truncated cone.

[0011] According to the above configuration, the light can be emitted from the exit surface in directions within a range of 180°. [Aspect 5] An inner lens comprising an annular frame and a lens according to any one of [Aspects 1] to [Aspect 4] provided on the frame, wherein the exit surface of the lens faces inward of the frame.

[0012] According to the above configuration, the light from the light source can be emitted toward the inside of the frame by the lens provided in the frame. [Aspect 6] A light emitting device comprising a bottomed box-shaped housing having an opening, an inner lens described in [Aspect 5] arranged within the housing, a light source arranged within the housing opposite the focusing portion of the lens, and a cover member that covers the opening and has a translucent portion through which the light passes.

[0013] According to the above configuration, the lens provided in the frame of the inner lens inside the housing emits light from the light source toward the inside of the inner lens. Therefore, even if the light-transmitting portion is located in the center of the cover member, the light from the light source passes through the light-transmitting portion and is emitted to the outside of the housing, allowing the light-transmitting portion to emit light in an optimal manner. [Effects of the Invention]

[0014] The present invention can direct the light of the light source over a wider range. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 2 is a cross-sectional view of an embodiment of a light-emitting emblem. [Figure 2] FIG. 2 is a front view of the inner lens. [Figure 3] FIG. [Figure 4] FIG. 2 is a perspective view of the lens as viewed from the light collecting portion side. [Figure 5] FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 5. [Figure 7] FIG. 10 is an end view showing a state in which light from a light-emitting element is guided by a lens. DETAILED DESCRIPTION OF THE INVENTION

[0016] An embodiment in which the light emitting device is embodied in a light emitting emblem for a vehicle will be described below with reference to the drawings. <Luminous Emblem 11> As shown in Fig. 1, an illuminating emblem 11, which is an example of a light-emitting device, is attached to the front grille of a vehicle for use, for example. The illuminating emblem 11 includes a housing 12, a substrate 13, an inner lens 14, a millimeter-wave sensor 15, and a cover member 16. Note that the front-rear direction, left-right direction, and up-down direction shown in Figs. 1 and 2 respectively correspond to the front-rear direction, left-right direction (vehicle width direction), and up-down direction of the vehicle when the traveling direction of the vehicle is the forward direction.

[0017] <Housing 12> As shown in Fig. 1, the housing 12 is shaped like a bottomed box having a bottom wall 17 and peripheral walls 18. The housing 12 has an opening 19 at the front end. The housing 12 is made of, for example, synthetic resin. The housing 12 accommodates a substrate 13, an inner lens 14, and a millimeter-wave sensor 15 inside.

[0018] <Board 13> As shown in FIG. 1, the substrate 13 is an insulating glass epoxy substrate or the like on which a required circuit pattern is formed. The substrate 13 has a substantially rectangular ring shape. The substrate 13 is fixed to, for example, the housing 12 by a fixing portion (not shown). Light-emitting elements 21 as an example of a plurality of light sources and circuits (not shown) required for controlling each light-emitting element 21 are mounted on a mounting surface 20, which is the front surface of the substrate 13. The light-emitting elements 21 are configured, for example, by LEDs (Light Emitting Diodes) that emit visible light. The light-emitting elements 21 are arranged at intervals in the circumferential direction on the peripheral edge of the mounting surface 20.

[0019] <Inner lens 14> 1 and 2, the inner lens 14 is disposed on the front side of the substrate 13 so as to face the substrate 13 in the front-to-rear direction, and is fixed to, for example, the housing 12 by a fixing portion (not shown). The inner lens 14 includes a plate-shaped, approximately rectangular annular frame portion 22 corresponding to the substrate 13, and a plurality of lenses 23 (two in this example) formed integrally with the frame portion 22. The inner lens 14 is made of, for example, a transparent resin such as polycarbonate (PC).

[0020] The lenses 23 are arranged one at the top end and one at the bottom end in the center in the left-right direction on the front surface of the frame portion 22. That is, the two lenses 23 formed on the frame portion 22 face each other in the up-down direction. The lenses 23 are arranged facing the light-emitting elements 21 of the substrate 13 in the front-to-back direction, and guide light emitted from the light-emitting elements 21. In the inner lens 14, the lenses 23 are integrally formed with the frame portion 22 so that an exit surface 39, which will be described later, faces the center of the inside of the frame portion 22.

[0021] <Millimeter wave sensor 15> As shown in FIG. 1, the millimeter-wave sensor 15 is disposed inside the annular substrate 13 and the annular inner lens 14, approximately in the center of the housing 12. The millimeter-wave sensor 15 transmits millimeter waves, which are electromagnetic waves, toward the front of the vehicle and receives millimeter waves reflected by objects outside the vehicle, including preceding vehicles and pedestrians. Based on the transmitted and received millimeter waves, the millimeter-wave sensor 15 recognizes the objects outside the vehicle and detects the distance and relative speed between the vehicle and the objects. Millimeter waves are radio waves with a wavelength of 1 mm to 10 mm and a frequency of 30 GHz to 300 GHz.

[0022] <Cover member 16> 1, the cover member 16 has a plate shape and includes an outer lens 24 and an ornament portion 25 laminated on the front surface of the outer lens 24.

[0023] The outer lens 24 is fixed to the housing 12 so as to close the opening 19 of the housing 12. The outer lens 24 is a transparent member that guides light from the light-emitting element 21 inside the housing 12 to the ornament portion 25. The outer lens 24 is made of a transparent resin such as polycarbonate (PC). The outer lens 24 may contain a diffusing material such as a light-diffusing filler to enhance the light diffusion properties.

[0024] The ornament part 25 is attached to the outer lens 24 from the front side (outside) so as to cover the entire outer lens 24. The ornament part 25 has a central light-transmitting part 26 as an example of a light-transmitting part configured by a through-hole formed in the center, and an outer edge light-transmitting part 27 as an example of a transmitting part configured by a through-hole formed in the outer edge. A part of the outer lens 24 is exposed from the central light-transmitting part 26 and the outer edge light-transmitting part 27 of the ornament part 25.

[0025] The ornament portion 25 emits light that is guided by the outer lens 24 and passes through the central light-transmitting portion 26 and the outer edge light-transmitting portion 27. The areas of the ornament portion 25 other than the central light-transmitting portion 26 and the outer edge light-transmitting portion 27 are non-light-transmitting portions 28 that do not transmit light. The ornament portion 25 is made of a transparent resin such as polycarbonate (PC). The non-light-transmitting portions 28 of the ornament portion 25 are coated or plated with a light-blocking material, for example.

[0026] <Lens 23> 1, 3, 4, and 6, the lens 23 includes a lens body 29 and a light-collecting portion 30 formed integrally with the lens body 29. The light-collecting portion 30 faces the light-emitting element 21 and has an axis J that extends in a direction facing the light-emitting element 21 and passes through the light-emitting element 21. In other words, the light-emitting element 21 is disposed in the housing 12 facing the light-collecting portion 30 of the lens 23.

[0027] 3 to 6, the light collecting section 30 has a cylindrical first convex portion 31 that protrudes from the lens body 29 toward the light emitting element 21, and a spherical crown-shaped second convex portion 32 that protrudes from the lens body 29 toward the light emitting element 21 and is disposed inside the first convex portion 31. The amount of protrusion of the first convex portion 31 from the lens body 29 along the axis J is at least twice the amount of protrusion of the second convex portion 32 from the lens body 29 along the axis J. The outer peripheral surface of the first convex portion 31 forms an inclined surface 33 that is inclined in the direction in which the axis J extends so that the outer diameter becomes smaller as it approaches the light emitting element 21.

[0028] Lens body 29 includes a reflecting surface forming portion 34 having a semiconical shape centered on axis J, and an exit surface forming portion 35 having a truncated semiconical shape centered on axis J. Reflecting surface forming portion 34 and exit surface forming portion 35 are integrally formed with their flat surfaces facing each other. A reflecting surface forming recess 36 having a semiconical shape centered on axis J is provided at the end of exit surface forming portion 35 opposite to the light collecting portion 30 side.

[0029] The side surface of the semicone that forms the reflecting surface forming portion 34 is a first reflecting surface 37, which is an example of a reflecting surface. The side surface of the semicone that forms the reflecting surface forming recess 36 is a second reflecting surface 38, which is an example of a reflecting surface. The first reflecting surface 37 and the second reflecting surface 38 are both curved surfaces that form the side surfaces of a semicone. The first reflecting surface 37 and the second reflecting surface 38 are continuous and flush with each other. The first reflecting surface 37 and the second reflecting surface 38 both form an arc shape centered on the axis J in a cross section when cut along a plane perpendicular to the axis J.

[0030] The distance between the first reflecting surface 37 and the axis J decreases as the first reflecting surface 37 moves away from the light collecting unit 30 in the direction in which the axis J extends. The distance between the second reflecting surface 38 and the axis J increases as the second reflecting surface 38 moves away from the light collecting unit 30 in the direction in which the axis J extends. Both the first reflecting surface 37 and the second reflecting surface 38 reflect the light of the light-emitting element 21 that has been collected by the light collecting unit 30.

[0031] The side surface of the truncated semicone that forms the exit surface forming portion 35 serves as an exit surface 39 that emits light reflected by the first reflecting surface 37 and the second reflecting surface 38. The exit surface 39 is a curved surface that forms the side surface of the truncated semicone. The exit surface 39 has an arc shape centered on the axis J in a cross section when cut along a plane perpendicular to the axis J. The distance between the exit surface 39 and the axis J decreases as the exit surface moves away from the light collecting portion 30 in the direction in which the axis J extends.

[0032] <Operation of the embodiment> 1, when the illuminating emblem 11 is illuminated, light is first emitted from each light-emitting element 21 mounted on the mounting surface 20 of the substrate 13 inside the housing 12. The light emitted from the light-emitting element 21 that is not facing the lens 23 in the front-to-rear direction is guided by the outer lens 24, causing the outer edge light-transmitting portion 27 of the ornament portion 25 to illuminate.

[0033] 7, light emitted from light-emitting element 21 facing lens 23 in the front-to-rear direction is collected by light-collecting section 30 of lens 23 and reflected by first reflecting surface 37 and second reflecting surface 38. At this time, first reflecting surface 37 and second reflecting surface 38 cover a range of 180° around axis J, so the light collected by light-collecting section 30 is reflected in directions within a range of 180° around axis J and guided to light exit surface 39.

[0034] The light guided to this exit surface 39 passes through the exit surface 39 and is emitted to the outside. At this time, the exit surface 39 covers a range of 180° centered on the axis J, similar to the first reflecting surface 37 and the second reflecting surface 38. Therefore, the exit surface 39 emits the light reflected by the first reflecting surface 37 and the second reflecting surface 38 in directions within a range of 180° centered on the axis J, as indicated by the two-dot chain arrows in FIG. 5 .

[0035] As a result, as shown in Figure 1, the light emitted from the exit surface 39 is guided over a wide area throughout the central portion of the cover member 16, and then guided by the outer lens 24 to cause the central translucent portion 26 of the ornament portion 25 to emit light.

[0036] Thus, in the luminous emblem 11, even if the light emitting element 21 cannot be positioned in the center of the mounting surface 20 of the substrate 13 due to the positioning of the millimeter wave sensor 15, the light from the light emitting element 21 positioned on the periphery of the mounting surface 20 can be guided by the lens 23 over a wide area across the entire central portion of the cover member 16. Therefore, the light from the light emitting element 21 guided by the lens 23 can be used to suitably illuminate the central translucent portion 26 located in the central portion of the cover member 16.

[0037] <Effects of the embodiment> According to the embodiment described above in detail, the following effects are achieved. (1) In the lens 23, the first reflecting surface 37 and the second reflecting surface 38 each have an arc shape centered on the axis J in a cross section taken along a plane perpendicular to the axis J. The distance between the first reflecting surface 37 and the axis J decreases with increasing distance from the light collecting unit 30 in the direction in which the axis J extends. The distance between the second reflecting surface 38 and the axis J increases with increasing distance from the light collecting unit 30 in the direction in which the axis J extends.

[0038] According to the above configuration, the first reflecting surface 37 and the second reflecting surface 38 are arc-shaped curved surfaces centered on the axis J of the light collecting unit 30, and therefore, light can be reflected in a wider range of directions than when the first reflecting surface 37 and the second reflecting surface 38 are flat surfaces. Therefore, the light from the light-emitting element 21 can be guided over a wider range.

[0039] (2) In the lens 23, the first reflecting surface 37 and the second reflecting surface 38 are curved surfaces that form the side surfaces of a semi-cone. According to the above configuration, the first reflecting surface 37 and the second reflecting surface 38 can reflect light in directions within a range of 180°.

[0040] (3) In lens 23, exit surface 39 has an arc shape centered on axis J in a cross section taken along a plane perpendicular to axis J. The distance between exit surface 39 and axis J decreases as the exit surface moves away from light-collecting unit 30 in the direction in which axis J extends.

[0041] According to the above configuration, the exit surface 39 is an arc-shaped curved surface centered on the axis J of the light collecting unit 30, so the exit surface 39 can be made smaller than if the exit surface 39 were flat, which can contribute to the miniaturization of the lens 23.

[0042] (4) In the lens 23, the exit surface 39 is a curved surface that forms the side surface of a semicircular truncated cone. According to the above configuration, light can be emitted from the exit surface 39 in directions within a range of 180°.

[0043] (5) The inner lens 14 includes an annular frame 22 and a lens 23 provided in the frame 22. An exit surface 39 of the lens 23 faces inward of the frame 22. According to the above configuration, the light from the light emitting element 21 can be emitted toward the inside of the frame portion 22 by the lens 23 provided in the frame portion 22 .

[0044] (6) The luminous emblem 11 comprises a bottomed box-shaped housing 12 having an opening 19, an inner lens 14 arranged within the housing 12, a light-emitting element 21 arranged within the housing 12 opposite the light-collecting portion 30 of the lens 23, and a cover member 16 that covers the opening 19 and has a central translucent portion 26 through which light passes.

[0045] According to the above configuration, the lens 23 provided on the frame portion 22 of the inner lens 14 inside the housing 12 emits light from the light-emitting element 21 toward the inside of the inner lens 14. Therefore, light from the light-emitting element 21, which is located at a position facing the peripheral portion of the cover member 16, can be sufficiently guided to the central light-transmitting portion 26, which is located in the center of the cover member 16. Therefore, most of the light from the light-emitting element 21 passes through the central light-transmitting portion 26 and is emitted to the outside of the housing 12, allowing the central light-transmitting portion 26 to emit light in an appropriate manner.

[0046] <Example of change> The above embodiment can be modified as follows: Furthermore, the above embodiment and the following modifications can be combined with each other within the scope of technical compatibility.

[0047] The light exit surface 39 of the lens 23 may be a curved surface that forms the side surface of a part of a truncated cone having an angle range smaller than that of a semi-frustum of a cone. The exit surface 39 of the lens 23 may be formed of one or more flat surfaces.

[0048] The first reflecting surface 37 and the second reflecting surface 38 of the lens 23 may be curved surfaces that form the side surfaces of a part of a cone with an angle range smaller than that of a semi-cone. In the lens 23, either the first reflecting surface 37 or the second reflecting surface 38 may be omitted.

[0049] In the inner lens 14, the lens 23 may be formed as a separate member from the frame portion 22. In this case, the lens 23 is attached by, for example, gluing or fitting into a hole formed in the frame portion 22.

[0050] In the inner lens 14, the number of lenses 23 formed in the frame portion 22 may be changed as appropriate, for example, to one, three or more. The arrangement of the lenses 23 formed in the frame portion 22 may also be changed as appropriate.

[0051] The luminous emblem 11 may omit the millimeter wave sensor 15. The luminous emblem 11 may be applied to vehicles other than automobiles. The light emitting device is not limited to the light emitting emblem 11, but may be used for decorating the interior and exterior of a vehicle such as a car, or for decorating the interior and exterior of a building. [Explanation of symbols]

[0052] 11...Luminous emblem as an example of a luminous device 12. Housing 13... Circuit board 14...Inner lens 15...Millimeter wave sensor 16...Cover member 17...Bottom wall 18...Peripheral wall 19...Opening 20...Mounting surface 21...Light emitting element as an example of a light source 22...Frame 23...Lens 24...Outer lens 25...Ornament section 26...Central light-transmitting portion as an example of a light-transmitting portion 27...Outer edge light-transmitting portion as an example of a light-transmitting portion 28…Non-transparent part 29...Lens body 30...Light collecting part 31...First convex part 32...Second convex part 33…Slope surface 34…Reflecting surface forming part 35...Emission surface forming section 36...Reflective surface forming recess 37...First reflecting surface as an example of a reflecting surface 38...Second reflecting surface as an example of a reflecting surface 39...Exit surface J…Axis line

Claims

1. A lens that guides light emitted from a light source, a light collecting portion facing the light source, extending in a direction facing the light source and having an axis passing through the light source; a reflecting surface that reflects the light collected by the light collecting unit; an exit surface that emits the light reflected by the reflecting surface; Equipped with The lens is characterized in that the reflective surface has an arc shape centered on the axis when viewed in cross section when cut along a plane perpendicular to the axis, and the distance from the axis becomes shorter or longer as the reflective surface moves away from the focusing section in the direction in which the axis extends.

2. 2. The lens according to claim 1, wherein the reflecting surface is a curved surface forming a side surface of a semi-cone.

3. 3. The lens according to claim 1, wherein the exit surface has an arc shape centered on the axis when viewed in cross section along a plane perpendicular to the axis, and the distance from the axis decreases as the exit surface moves away from the light-condensing portion in the direction in which the axis extends.

4. 3. The lens according to claim 1, wherein the light exit surface is a curved surface forming a side surface of a semicircular truncated cone.

5. an annular frame portion; The lens according to claim 1 or 2 provided on the frame portion; Equipped with An inner lens, characterized in that the light exit surface of the lens faces inward of the frame portion.

6. a box-shaped housing having a bottom and an opening; The inner lens according to claim 5 disposed within the housing; a light source disposed in the housing opposite the light-collecting portion of the lens; a cover member that covers the opening and has a light-transmitting portion through which the light passes; A light emitting device comprising:

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