Lens components, lighting devices, and lighting fixtures

Abstract

To provide lens components, lighting devices, and lighting fixtures capable of reducing color unevenness. [Solution] The lens member is a lens member into which light from a light source can be incident. The lens member comprises: a first incident surface into which the optical axis of the light source intersects and into which first light, including light emitted in the direction in which the optical axis extends, is incident; a second incident surface, in a top view, that surrounds the first incident surface and has first irregularities along the circumferential direction surrounding the optical axis, into which second light, different from the first light, is incident; a reflective surface that surrounds the optical axis and has second irregularities along the circumferential direction, and totally reflects the light incident from the second incident surface; and an exit surface that emits the light reflected by the reflective surface and the light incident from the first incident surface.

Description

Technical Field

[0001] The present disclosure relates to a lens member, a lighting device, and a lighting fixture.

Background Art

[0002] In a lighting device where it is desired to limit the lighting range such as a downlight, a lens member may be combined with a light source to control the traveling direction of light. In this case, the structure of the light source may be projected onto the projection surface by the lens member. If the structure of the light source is symmetric, the problem is less likely to become apparent, but when the structure of the light source is asymmetric, color unevenness may occur on the projection surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present disclosure is to provide a lens member, a lighting device, and a lighting fixture capable of reducing color unevenness.

Means for Solving the Problems

[0005] The lens member according to this disclosure is a lens member to which light from a light source can be incident. The lens member comprises: a first incident surface to which the optical axis of the light source intersects and to which first light, including light emitted in the direction in which the optical axis extends, is incident; a second incident surface to which second light, different from the first light, is incident, surrounds the first incident surface in a top view and has first irregularities along the circumferential direction surrounding the optical axis; a reflective surface to which light incident from the second incident surface is totally reflected, surrounds the optical axis and has second irregularities along the circumferential direction; and an exit surface to which light reflected by the reflective surface and light incident from the first incident surface are emitted.

[0006] The lighting device according to this disclosure comprises the light source and the lens member.

[0007] The illuminating device according to this disclosure comprises a first illuminating device and a second illuminating device. The first illuminating device has a first light source including a first light-emitting element, and a first lens member into which light from the first light source can be incident. The second illuminating device has a second light source including a second light-emitting element, and a second lens member into which light from the second light source can be incident. In a top view, the first direction from the center of the first light source toward the center of the first light-emitting element is different from the second direction from the center of the second light source toward the center of the second light-emitting element. [Effects of the Invention]

[0008] According to this disclosure, it is possible to realize lens components, lighting devices, and lighting fixtures that can reduce color unevenness. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a cross-sectional view showing a lighting device according to the first embodiment. [Figure 2] Figure 2 is a perspective view showing the light source of the lighting device according to the first embodiment. [Figure 3] Figure 3 is a top view showing the light source of the lighting device according to the first embodiment. [Figure 4]Figure 4 is a cross-sectional view taken along the line IV-IV shown in Figure 2. [Figure 5] Figure 5 is a perspective view from the light source side showing the lens member according to the first embodiment. [Figure 6] Figure 6 is a side view showing a lens member according to the first embodiment. [Figure 7] Figure 7 is a bottom view showing a lens member according to the first embodiment. [Figure 8] Figure 8 is a perspective view of the lens member according to the first embodiment, seen from the opposite side of the light source. [Figure 9] Figure 9 is a perspective view showing the first incident surface of the lens member according to the first embodiment. [Figure 10] Figure 10 is a cross-sectional view showing a lens member according to the first embodiment. [Figure 11] Figure 11 is a partially enlarged cross-sectional view showing region XI in Figure 10. [Figure 12] Figure 12 shows the second incident surface and the reflective surface in the first embodiment. [Figure 13] Figure 13 is a partially exploded perspective view showing the curves along the convex and concave portions of the second unevenness of the reflective surface. [Figure 14] Figure 14 is a partial side view showing the curves along the convex and concave portions of the second unevenness of the reflective surface. [Figure 15] Figure 15 is a graph showing the change in curvature in the circumferential direction, with the horizontal axis representing the angle in the circumferential direction and the vertical axis representing the curvature of the reflective surface. [Figure 16] Figure 16 is a top view showing the second incident surface, the reflective surface, and some of the light rays of the lens member according to the first embodiment. [Figure 17] Figure 17 is a top view showing the second incident surface, the reflective surface, and some of the light rays of a lens member according to a comparative example. [Figure 18] Figure 18 is a top view showing the light source of a lighting device according to a first modification of the first embodiment. [Figure 19] Figure 19 is a top view showing the light source of a lighting device according to a second modification of the first embodiment. [Figure 20] FIG. 20 is a top view showing a light source of a lighting device according to a third modification of the first embodiment. [Figure 21] FIG. 21 is a partial cross-sectional view showing a lens member according to the second embodiment. [Figure 22] FIG. 22 is a view showing a second incident surface and a reflection surface in the second embodiment. [Figure 23] FIG. 23 is a perspective view of a lens member according to the third embodiment as viewed from the opposite side of the light source. [Figure 24] FIG. 24 is a perspective view of a lens member according to the fourth embodiment as viewed from the opposite side of the light source. [Figure 25A] FIG. 25A is a graph showing a cross-sectional shape of an exit surface, with the position in the X direction taken on the horizontal axis and the position in the Z direction taken on the vertical axis. [Figure 25B] FIG. 25B is a graph showing a cross-sectional shape of an exit surface, with the position in the Y direction taken on the horizontal axis and the position in the Z direction taken on the vertical axis. [Figure 26] FIG. 26 is a top view showing a lens member according to the fifth embodiment. [Figure 27A] FIG. 27A is a graph showing a sine curve. [Figure 27B] FIG. 27B is a perspective view showing the shape of a convex portion of an exit surface. [Figure 27C] FIG. 27C is a cross-sectional view taken along the XXVII C plane shown in FIG. 27B. [Figure 28] FIG. 28 is a perspective view of a lens member according to the sixth embodiment as viewed from the opposite side of the light source. [Figure 29] FIG. 29 is a top view showing a part of a lens member according to the seventh embodiment. [Figure 30A] FIG. 30A is a graph showing the shape of an exit surface, with the position in the radial direction R taken on the horizontal axis and the position in the Z direction taken on the vertical axis. [Figure 30B] FIG. 30B is a graph showing the shape of an exit surface, with the position in the circumferential direction W taken on the horizontal axis and the position in the Z direction taken on the vertical axis. [Figure 31A]Figure 31A is a perspective view showing the design concept of the lens member according to the eighth embodiment. [Figure 31B] Figure 31B is a perspective view showing the design concept of the lens member according to the eighth embodiment. [Figure 32] Figure 32 is a top view showing a lens member according to the eighth embodiment. [Figure 33] Figure 33 is a perspective view showing a part of the lens member according to the eighth embodiment. [Figure 34A] Figure 34A is a graph showing the shape of the ejection surface along the XXXIVA line shown in Figure 33, with the horizontal axis representing the position in the radial direction R and the vertical axis representing the position in the Z direction. [Figure 34B] Figure 34B is a graph showing the shape of the ejection surface along the XXXIVB line shown in Figure 33, with the horizontal axis representing the position in the radial direction R and the vertical axis representing the position in the Z direction. [Figure 35A] Figure 35A is a graph showing the WZ cross-sectional shape of the emission surface, with the horizontal axis representing the position in the circumferential direction W and the vertical axis representing the position in the Z direction. [Figure 35B] Figure 35B is a graph showing the WZ cross-sectional shape of the emission surface, with the horizontal axis representing the position in the circumferential direction W and the vertical axis representing the position in the Z direction. [Figure 36] Figure 36 is a top view showing a lighting fixture according to the ninth embodiment. [Figure 37A] Figure 37A shows the simulation method used in the test example. [Figure 37B] Figure 38B shows the simulation method used in the test example. [Figure 38A] Figure 38A is a graph showing the simulation results of a lighting device related to a comparative example, with the horizontal axis representing the position in the X direction and the vertical axis representing the position in the Y direction. [Figure 38B] Figure 38B is a graph showing the simulation results of the lighting device according to the second embodiment, with the horizontal axis representing the position in the X direction and the vertical axis representing the position in the Y direction. [Figure 38C]Figure 38C is a graph showing the simulation results of the lighting device according to the first embodiment, with the horizontal axis representing the position in the X direction and the vertical axis representing the position in the Y direction. [Modes for carrying out the invention]

[0010] <First Embodiment> (Lighting equipment) Figure 1 is a cross-sectional view showing a lighting device according to this embodiment.

[0011] As shown in Figure 1, the lighting device 1 according to this embodiment comprises a light source 200 and a lens member 100. The light source 200 is arranged on a substrate 900. Light from the light source 200 can enter the lens member 100.

[0012] Hereafter, for the sake of explanation, the XYZ Cartesian coordinate system will be adopted in this specification. The direction in which the optical axis 200C of the light source 200 extends, and the direction from the light source 200 toward the lens member 100, will be defined as the "Z direction," and the two directions perpendicular to the Z direction and mutually orthogonal will be defined as the "X direction" and the "Y direction." The Z direction is also referred to as "up," and its opposite direction as "down," but this expression is for convenience only and is unrelated to the direction of gravity. In this specification, "top view" means viewing from the Z direction. In the top view, components that are actually hidden from view by other components may be described as visible. Also, all figures are schematic and have been emphasized or simplified as appropriate. For example, even for the same component, the shape and dimensional ratios may not be strictly consistent between figures.

[0013] (light source) Figure 2 is a perspective view showing the light source of the lighting device according to this embodiment. Figure 3 is a top view showing the light source of the lighting device according to this embodiment. Figure 4 is a cross-sectional view taken along the line IV-IV shown in Figure 2.

[0014] As shown in Figures 2 to 4, the light source 200 includes a housing 201, two light-emitting elements 202 and 203, a wavelength conversion member 204, a wavelength conversion member 205, a light-transmitting member 206, and a lead 207. The housing 201 is made of an insulating material and has a box-like shape with an opening on the Z-direction side. The outer shape of the housing 201, including the opening, is, for example, a rectangular parallelepiped.

[0015] The light-emitting elements 202 and 203 are arranged at the bottom of the housing 201, spaced apart from each other in the X direction. The light-emitting elements 202 and 203 emit light primarily in the Z direction. The light-emitting elements 202 and 203 are, for example, LEDs (Light Emitting Diodes). For example, light-emitting elements 202 and 203 are LEDs of the same specifications, and the peak wavelengths of the emitted light are the same. In this specification, "same" means that the design values ​​are the same, and errors that inevitably occur due to variations in process conditions, etc., are ignored. However, the light-emitting elements 202 and 203 may be LEDs of different specifications, and the peak wavelengths of the emitted light may be different from each other.

[0016] The wavelength conversion member 204 is positioned on the light-emitting element 202. The wavelength conversion member 204 converts the peak wavelength of the light emitted from the light-emitting element 202. The light-transmitting member 206 is positioned on the light-emitting element 203. The wavelength conversion member 205 is positioned to cover the light-emitting elements 202 and 203, the wavelength conversion member 204, and the light-transmitting member 206. The wavelength conversion member 205 converts the peak wavelength of the light emitted from the light-emitting elements 202 and 203. The wavelength conversion members 204 and 205 include, for example, a phosphor. For example, the wavelength conversion member 204 includes an SCASN phosphor, and the wavelength conversion member 205 includes a YAG-based phosphor. The light-transmitting member 206 does not include a phosphor. The wavelength conversion member 205 constitutes the light-emitting surface of the light source 200. The side surface of the wavelength conversion member 205 is in contact with the inner surface of the housing 201 around its entire circumference. In other words, in a top view, the wavelength conversion member 205 is arranged throughout the interior of the housing 201. The lead 207 is connected to the electrodes of the light-emitting elements 202 and 203 and is exposed on the side of the housing 201. Note that the lead 207 is omitted from the illustration in Figure 4.

[0017] In the light source 200, light emitted from the light-emitting element 202 passes through the wavelength conversion members 204 and 205 before being emitted from the light source 200. Therefore, the peak wavelength of the light emitted from the light-emitting element 202 is converted by the wavelength conversion members 204 and 205. Light emitted from the light-emitting element 203 passes through the light-transmitting member 206 and the wavelength conversion member 205 before being emitted from the light source 200. Therefore, the peak wavelength of the light emitted from the light-emitting element 203 is converted only by the wavelength conversion member 205. By adjusting the emission intensity ratio of the light-emitting elements 202 and 203, the light emitted from the entire light source 200 can be color-tuned from incandescent to white.

[0018] In this embodiment, in a top view, the center 205c of the wavelength conversion member 205 is located at the center of the light source 200, i.e., at the center of the housing 201. On the other hand, the centers 202c of the light-emitting element 202 and 203c of the light-emitting element 203 are located on the Y-direction side of the center of the light source 200. Therefore, in a top view, the center 205c of the wavelength conversion member 205 does not coincide with the centers 202c of the light-emitting element 202 and 203c of the light-emitting element 203. The centers 202c of the light-emitting element 202 and 203c of the light-emitting element 203 also do not coincide with the center of the light source 200. Thus, the configuration of the light source 200 is asymmetric with respect to the optical axis 200C of the light source 200. The optical axis 200C passes through the center of the housing 201 and the center 205c of the wavelength conversion member 205.

[0019] (Lens component) Figure 5 is a perspective view from the light source side showing the lens member according to this embodiment. Figure 6 is a side view showing the lens member according to this embodiment. Figure 7 is a bottom view showing the lens member according to this embodiment. Figure 8 is a perspective view of the lens component according to this embodiment, seen from the opposite side of the light source. Figure 9 is a perspective view showing the first incident surface of the lens member according to this embodiment. Figure 10 is a cross-sectional view showing a lens member according to this embodiment. Figure 11 is a partially enlarged cross-sectional view showing region XI in Figure 10.

[0020] As shown in Figures 5 to 7, the lens member 100 has a first incident surface 101, a second incident surface 102, a reflective surface 103, and an exit surface 104. The lens member 100 is integrally formed from, for example, a transparent resin material.

[0021] The lens member 100 has a roughly frustoconical shape, with a roughly cylindrical recess formed on the top surface of the frustoconical. The interior of this recess is a roughly cylindrical space, and the inner surface of the recess is composed of an inner bottom surface and an inner side surface. The inner bottom surface of the recess is the first incident surface 101, and the inner side surface of the recess is the second incident surface 102. The outer side surface of the frustoconical is the reflecting surface 103, and the outer bottom surface of the frustoconical is the exit surface 104. An annular region 105 may be positioned between the second incident surface 102 and the reflecting surface 103. An annular plate-shaped flange 106 may be provided between the reflecting surface 103 and the exit surface 104. In Figure 1, the annular region 105 is omitted from the illustration. In Figure 5, the flange 106 is omitted from the illustration.

[0022] As described above, the shape of the lens member 100 is approximately a frustoconical shape, and therefore the lens member 100 has a central axis. The lens member 100 is positioned so that its central axis coincides with the optical axis 200C of the light source 200. Hereafter, the central axis of the lens member 100 will be referred to as the "optical axis 200C".

[0023] As shown in Figures 1, 5 to 9, the optical axis 200C of the light source 200 intersects the first incident surface 101. The first light L1 from the light source 200, which includes light emitted in the Z direction, i.e., in the direction in which the optical axis 200C extends, is incident on the first incident surface 101. The first incident surface 101 protrudes in a convex lens shape toward the light source 200 and has a third concave / concave shape 101A along the circumferential direction W surrounding the optical axis 200C. The circumferential direction W is the direction that circles the optical axis 200C on the XY plane. On the first incident surface 101, convex and concave portions are arranged alternately along the circumferential direction W. Note that the third concave / concave shape 101A is not required on the first incident surface 101, and it may be a simple convex lens surface, a flat surface, or a concave lens surface.

[0024] As shown in Figures 1, 5 to 11, the second incident surface 102 is a cylindrical region surrounding the first incident surface 101 in a top view. The second light L2, which is different from the first light L1, is incident on the second incident surface 102 from the light source 200. The second incident surface 102 has a first uneven surface 102A along the circumferential direction W surrounding the optical axis 200C. In the first uneven surface 102A, convex portions and concave portions are arranged alternately and periodically along the circumferential direction W. In this specification, "convex portion" and "concealed portion" are based on the inside of the lens member 100. Therefore, in any XY cross section, the distance between the vertex of the convex portion of the first uneven surface 102A and the optical axis 200C is shorter than the distance between the vertex of the concave portion of the first uneven surface 102A and the optical axis 200C.

[0025] In the first uneven surface 102A, the number of protrusions arranged along the circumferential direction W is preferably 4 to 36, more preferably 6 to 18, and for example, preferably 12. When the number of protrusions is 12, the angle between the two directions from the optical axis 200C toward two adjacent protrusions is 30°.

[0026] The reflective surface 103 surrounds the optical axis 200C and is inclined with respect to the Z direction such that it moves further away from the optical axis 200C as it moves toward the Z direction. The reflective surface 103 totally reflects the second light L2 incident from the second incident surface 102. The reflective surface 103 has second irregularities 103A along the circumferential direction W. The positional relationship of the second irregularities 103A with respect to the optical axis 200C is the opposite of that of the first irregularities 102A. In any XY cross section, the distance between the vertex of the convex part of the second irregularities 103A and the optical axis 200C is longer than the distance between the vertex of the concave part of the second irregularities 103A and the optical axis 200C.

[0027] In the second uneven surface 103A, the number of protrusions arranged along the circumferential direction W is preferably 4 to 36, more preferably 6 to 18, and for example, preferably 12. The number of protrusions in the second uneven surface 103A is, for example, equal to the number of protrusions in the first uneven surface 102A.

[0028] As shown in Figure 8, the shape of the emission surface 104 is, for example, approximately circular. The emission surface 104 emits the second light L2 reflected by the reflecting surface 103 and the first light L1 incident from the first incident surface 101. In this embodiment, the emission surface 104 is, for example, flat. For example, the emission surface 104 is continuous with the upper surface of the flange portion 106.

[0029] The following describes the positional relationship between the first irregularities 102A of the second incident surface 102 and the second irregularities 103A of the reflective surface 103. Figure 12 shows the second incident surface and the reflective surface in this embodiment. Figure 12 shows an exaggerated depiction of only the first and second contours 102A and 103A in an XY cross-section of the lens member 100. In Figure 12, the angle in the circumferential direction W is expressed as angle θ(°), with the direction from the optical axis 200C toward the convex portion with the second concave / concave 103A as the reference.

[0030] As shown in Figures 10 to 12, in the XY cross section perpendicular to the optical axis 200C, we assume a first straight line S1 that passes through the optical axis 200C and one convex portion of the second unevenness 103A, and a second straight line S2 that passes through the optical axis 200C and one concave portion of the second unevenness 103A. In this embodiment, the first straight line S1 passes through the convex portion of the first unevenness 102A, and the second straight line S2 passes through the concave portion of the first unevenness 102A. In other words, as viewed from the optical axis 200C, the convex portion of the first unevenness 102A on the second incident surface 102 coincides with the convex portion of the second unevenness 103A on the reflecting surface 103, and the concave portion of the first unevenness 102A on the second incident surface 102 coincides with the concave portion of the second unevenness 103A on the reflecting surface 103.

[0031] Let the distance between the second incident surface 102 and the reflecting surface 103 in the first straight line S1 be the first distance D1, and let the distance between the second incident surface 102 and the reflecting surface 103 in the second straight line S2 be the second distance D2. The first distance D1 is different from the second distance D2. In this embodiment, the first distance D1 is longer than the second distance D2. That is, D1 > D2.

[0032] The absolute value of the difference between the first distance D1 and the second distance D2 is preferably 1% or more of the second distance D2, and more preferably 5% or more. That is, it is preferably |D1-D2|≧D2 / 100, and more preferably |D1-D2|≧D2×5 / 100. In one example, D1=2.09mm and D2=1.83mm. In this case, the absolute value of the difference between the first distance D1 and the second distance D2 is 0.26mm, which corresponds to 14.2% of the second distance D2.

[0033] The number of protrusions in the third recess 101A of the first incident surface 101 is also equal to the number of protrusions in the first recess 102A, for example, 12. For example, as shown in Figure 11, in a top view, the protrusions of the first recess 102A face the recesses of the third recess 101A, and the recesses of the first recess 102A face the protrusions of the third recess 101A. However, the number of protrusions in the third recess 101A and its positional relationship with the first recess 102A are not limited to this.

[0034] Next, we will describe the shape of the reflective surface 103 along the Z direction. Figure 13 is a partially exploded perspective view showing the curves along the convex and concave portions of the second unevenness of the reflective surface. Figure 14 is a partial side view showing the curves along the convex and concave portions of the second unevenness of the reflective surface. Figure 15 is a graph showing the change in curvature in the circumferential direction, with the horizontal axis representing the angle in the circumferential direction and the vertical axis representing the curvature of the reflective surface.

[0035] As shown in Figure 14, in a cross-section including the Z direction, the second incident surface 102 is gently concave, and the reflective surface 103 is gently convex. As shown in Figures 13 and 14, the lens member 100 is assumed to have a first cross-section B1 including the optical axis 200C and the first straight line S1. The lens member 100 is also assumed to have a second cross-section B2 including the optical axis 200C and the second straight line S2. In this case, the curvature c1 of the reflective surface 103 in the first cross-section B1 is greater than the curvature c2 of the reflective surface 103 in the second cross-section B2. In other words, the radius of curvature r1 of the reflective surface 103 in the first cross-section B1 is smaller than the radius of curvature r2 of the reflective surface 103 in the second cross-section B2. That is, the reflective surface 103 in the first cross-section B1 is more strongly curved than the reflective surface 103 in the second cross-section B2.

[0036] Furthermore, as shown in Figure 15, the curvature of the reflective surface 103 in the cross section that includes the optical axis 200C and is located between the first cross section B1 and the second cross section B2 is the value obtained by linearly interpolating the curvature c1 in the first cross section B1 and the curvature c2 in the second cross section B2 with respect to the angle θ.

[0037] As shown in Figure 1, light emitted from the light source 200, incident on the second incident surface 102, and reflected at the intersection line 107 (see Figure 10) of the XY cross section perpendicular to the optical axis 200C and the reflection surface 103 has a focal point P0. For example, the second beam L2_1 reflected at the first point P1 on the intersection line 107 and emitted from the exit surface 104, and the second beam L2_2 reflected at the second point P2 on the intersection line 107 and emitted from the exit surface 104, intersect at the focal point P0. The focal point P0 is located, for example, on the optical axis 200C. The position of the focal point P0 in the Z direction may differ for each intersection line 107, may be the same for multiple intersection lines 107, or may be the same for all intersection lines 107.

[0038] (Effects and Benefits) Next, the effects and advantages of this embodiment will be described. Figure 16 is a top view showing the second incident surface, the reflective surface, and some of the light rays of the lens member according to this embodiment. In the explanation using Figure 16, the light emitted from the light source 200 is assumed to originate from the center of the light source 200. The same applies to Figure 17, which will be discussed later.

[0039] As shown in Figure 16, light La emitted from the light source 200 at an angle θ=0° reaches the apex of the convex portion of the first unevenness 102A on the second incident surface 102. When viewed from above, it is incident on the second incident surface 102 at an incident angle of 0°, enters the lens member 100 while maintaining the angle θ, reaches the apex of the convex portion of the second unevenness 103A on the reflecting surface 103, is incident on the reflecting surface 103 at an incident angle of 0° when viewed from above, and is reflected at a reflection angle of 0°. Therefore, light La moves in the direction away from the optical axis 200C (hereinafter referred to as "radial direction R"), but does not move in the circumferential direction W. In other words, light La travels within a single plane that includes the optical axis 200C.

[0040] In contrast, light Lb emitted in a direction slightly offset from light La with respect to angle θ reaches a position slightly offset from the apex of the convexity of the second incident surface 102. In this case, when viewed from above, the angle of incidence of light Lb with respect to the second incident surface 102 is no longer 0°, and the direction of propagation of the refracted light Lb has components not only in the radial direction R but also in the circumferential direction W. When this light Lb reaches the reflective surface 103, it reaches a position offset from the apex of the convexity of the reflective surface 103, so the angle of incidence of light Lb with respect to the reflective surface 103 is no longer 0°, and the direction of propagation of the reflected light Lb has components not only in the radial direction R but also in the circumferential direction W.

[0041] Furthermore, light Lc emitted in a direction further deviated from light Lb with respect to angle θ has an incident angle with respect to the second incident surface 102 that is different from that of light La and light Lb, and an incident angle with respect to the reflecting surface 103 that is also different from that of light La and light Lb, and is reflected in a direction different from that of light La and light Lb with respect to the circumferential direction W.

[0042] Thus, even a slight difference in the angle θ of the direction of light propagation results in a significant difference in the direction of propagation after reflection from the reflective surface 103 with respect to the circumferential direction W. As a result, the light is mixed with respect to the circumferential direction W. On the other hand, with respect to the radial direction R, the directions of propagation of the light La, Lb, and Lc after reflection from the reflective surface 103 are substantially the same. Therefore, the light is not substantially mixed with respect to the radial direction R. This allows the light to be mixed without expanding the illumination range of the projection surface. The "projection surface" is the plane that the lighting device 1 is intended to illuminate. For example, if the lighting device 1 is used as a downlight installed on the ceiling of a room, the projection surface is, for example, the floor of the room or the top surface of a desk.

[0043] As a result, the lens member 100 according to this embodiment can reduce the projection of the structure of the light source 200 onto the projection surface by mixing light along the circumferential direction W. Therefore, even if the structure of the light source 200 is asymmetric with respect to the optical axis 200C, the occurrence of color unevenness can be reduced. In addition, brightness unevenness caused by the asymmetry of the light source 200 can also be reduced.

[0044] This effect can be reliably obtained when the number of protrusions arranged along the circumferential direction W in the first unevenness 102A of the second incident surface 102 is between 4 and 36. If the number of protrusions is 3 or less, the slope of the protrusions becomes gentler, and even if the direction of light changes slightly, the incident angle does not change much. If the number of protrusions is 37 or more, the distance between protrusions becomes shorter, and in the above example, the light Lc may reach the vertex of the adjacent protrusion. In this case as well, the incident angle does not change much. As a result, the effect of mixing light along the circumferential direction W is reduced. If the number of protrusions is between 6 and 18, the effect of mixing light along the circumferential direction W can be obtained more reliably, and if the number of protrusions is 12, it can be obtained even more reliably.

[0045] Furthermore, in this embodiment, the absolute value of the difference between the first distance D1 and the second distance D2 is 1% or more of the second distance D2. This allows for effective mixing of light. It is more preferable that the absolute value of the difference is 5% or more of the second distance D2. Since the first straight line S1 passes through the convex portion of the first unevenness 102A and the convex portion of the second unevenness 103A, and the second straight line S2 passes through the concave portion of the first unevenness 102A and the concave portion of the second unevenness 103A, the first distance D1 can be made longer and the second distance D2 can be made shorter, thus increasing the absolute value of the difference between the first distance D1 and the second distance D2.

[0046] Furthermore, in this embodiment, as shown in Figures 13 and 14, the curvature c1 of the reflective surface 103 in the first cross-section B1 is greater than the curvature c2 of the reflective surface 103 in the second cross-section B2. Although the convex portion of the reflective surface 103 is further from the optical axis 200C than the concave portion, by making the curvature of the convex portion greater than the curvature of the concave portion, the light focusing performance in the radial direction R can be made more uniform. Also, as shown in Figure 15, by making the curvature of the reflective surface 103 in the cross-section located between the first cross-section B1 and the second cross-section B2, which includes the optical axis 200C, a value obtained by linearly interpolating the curvature c1 in the first cross-section B1 and the curvature c2 in the second cross-section B2 with respect to the angle θ, there are no points where the curvature changes discontinuously, and the concentration of light in the circumferential direction W can be reduced.

[0047] Furthermore, in this embodiment, as shown in Figure 1, each intersection line 107 has a focal point P0. This suppresses the spreading of light emitted from the lighting device 1 at positions close to the lighting device 1. As a result, for example, when the lighting device 1 is placed inside a cylindrical housing for use as a downlight, the amount of light emitted from the lighting device 1 reaching the inner surface of the cylindrical housing can be reduced, and therefore, irregular reflection on the inner surface of the housing can be reduced. This improves the controllability of the light.

[0048] Furthermore, in this embodiment, as shown in Figure 9, a third irregularity 101A is formed on the first incident surface 101. This allows the first light L1 incident on the first incident surface 101 to be mixed along the circumferential direction W.

[0049] <Comparative Example> Figure 17 is a top view showing the second incident surface, the reflective surface, and some of the light rays of a lens member according to a comparative example.

[0050] As shown in Figure 17, in the comparative example lens member, the second incident surface 102 does not have a first uneven surface 102A, the reflective surface 103 does not have a second uneven surface 103A, and the first incident surface 101 does not have a third uneven surface 101A. Therefore, in the XY cross-section, the shapes of the second incident surface 102 and the reflective surface 103 are circular.

[0051] Therefore, the light rays La, Lb, and Lc emitted from the light source 200, each with a different angle θ in the circumferential direction W, all enter the lens member at an incident angle of 0° when viewed from above and enter the lens member without refraction along the circumferential direction W. Furthermore, the light rays La, Lb, and Lc enter the reflective surface 103 at an incident angle of 0° when viewed from above and are reflected without changing their direction of propagation along the circumferential direction W. For this reason, the light is not mixed along the circumferential direction W at the second incident surface 102 and the reflective surface 103. Similarly, the light is not mixed along the circumferential direction W at the first incident surface 101.

[0052] In this case, the structure of the light source 200 may be projected onto the projection surface. For example, as shown in Figure 3, if the center 202c of the light-emitting element 202 and the center 203c of the light-emitting element 203 are offset from the center 205c of the wavelength conversion member 205 in the Y direction, the color may differ between the area onto which the light-emitting elements 202 and 203 are projected and the other areas on the projection surface of the lighting device. As a result, color unevenness occurs.

[0053] Furthermore, to mix the light, it is conceivable to install a diffuser or the like on the output side of the lens component. However, in this case, the light is mixed not only in the circumferential direction W but also in the radial direction R. As a result, the illumination range on the projection surface expands. Also, the illumination device becomes larger.

[0054] <First variation of the first embodiment> This modified example, as well as the second and third modified examples described later, are examples in which the light source configuration differs from that of the first embodiment. Figure 18 is a top view showing the light source of the lighting device according to this modified example.

[0055] As shown in Figure 18, in this modified light source 210, the peak wavelength of the light emitted from the light-emitting element 202 is different from the peak wavelength of the light emitted from the light-emitting element 203. Furthermore, the light source 210 does not have wavelength conversion members 204 and 205. Also, in a top view, the center 210c of the light source 210 does not overlap with the center 202c of the light-emitting element 202 and the center 203c of the light-emitting element 203.

[0056] According to this modified example, the color of the light emitted from the lighting device can be changed by controlling the output ratio of the light-emitting element 202 and the light-emitting element 203. For example, the color temperature and brightness of the light can be adjusted depending on the time of day or application. In one example, the color temperature can be set to daylight color at about 5000K during the day, and to incandescent color at about 2700K at night. Furthermore, according to this modified example, the color unevenness caused by the light-emitting elements 202 and 203 can be reduced by the action of the lens member 100. The configuration and effects of this modified example other than those described above are the same as those of the first embodiment.

[0057] <Second variation of the first embodiment> Figure 19 is a top view showing the light source of the lighting device according to this modified example. As shown in Figure 19, in this modified example, the light source 220 does not have a light-emitting element 202 and a wavelength conversion member 204. On the other hand, a light-emitting element 203 and a wavelength conversion member 205 are provided.

[0058] According to this modified example, the lens member 100 reduces color unevenness caused by the difference in position between the center 203c of the light-emitting element 203 and the center 205c of the wavelength conversion member 205. The configuration and effects of this modified example other than those described above are the same as those of the first embodiment.

[0059] <Third Modification of the First Embodiment> Figure 20 is a top view showing the light source of the lighting device according to this modified example. As shown in Figure 20, in the light source 230 of this modified example, the wavelength conversion member 205 is smaller compared to the light source 220 of the second modified example. The wavelength conversion member 205 is in contact with two adjacent sides on the inner surface of the housing 201, but not with the other two sides. In a top view, the wavelength conversion member 205 overlaps with the light-emitting element 203. In this modified example, the center 203c of the light-emitting element 203 and the center 205c of the wavelength conversion member 205 are offset from the center 230c of the light source 230.

[0060] According to this modified example, color unevenness caused by the offset of the center 203c of the light-emitting element 203 and the center 205c of the wavelength conversion member 205 from the center 230c of the light source 230 can be reduced by the action of the lens member 100. The configuration and effects of this modified example other than those described above are the same as those of the first embodiment.

[0061] <Second Embodiment> Figure 21 is a partial cross-sectional view showing a lens member according to this embodiment. Figure 22 shows the second incident surface and the reflective surface in this embodiment. Figure 22 shows an exaggerated depiction of only the first and second contours 102A and 103A in an XY cross-section of the lens member 120.

[0062] As shown in Figures 21 and 22, in the lens member 120 according to this embodiment, in the XY cross section perpendicular to the optical axis 200C, the first straight line S1 passing through the optical axis 200C and passing through one of the protrusions of the second unevenness 103A passes through the recess of the first unevenness 102A of the second incident surface 102, and the second straight line S2 passing through one of the recesses of the second unevenness 103A passes through the protrusion of the first unevenness 102A of the second incident surface 102. In other words, as viewed from the optical axis 200C, the protrusion of the first unevenness 102A of the second incident surface 102 coincides with the recess of the second unevenness 103A of the reflective surface 103, and the recess of the first unevenness 102A of the second incident surface 102 coincides with the protrusion of the second unevenness 103A of the reflective surface 103.

[0063] In this embodiment as well, the first distance D1 between the second incident surface 102 and the reflective surface 103 in the first straight line S1 is longer than the second distance D2 between the second incident surface 102 and the reflective surface 103 in the second straight line S2. In one example, D1 = 1.969 mm and D2 = 1.951 mm. In this case, the absolute value of the difference between the first distance D1 and the second distance D2 is 0.018 mm, which corresponds to 0.922% of the second distance D2.

[0064] This embodiment also provides effects similar to those of the first embodiment. The configuration and effects of this embodiment other than those described above are the same as those of the first embodiment.

[0065] <Third Embodiment> Figure 23 is a perspective view of the lens member according to this embodiment, seen from the opposite side of the light source. As shown in Figure 23, in the lens member 130 according to this embodiment, the exit surface 104 has a microlens array. On the exit surface 104, a plurality of lens elements 131 are arranged in a hexagonal close-packed manner. The shape of each lens element 131 is convex lens-like.

[0066] According to this embodiment, light can be mixed at the exit surface 104. This allows for further mixing of the second light L2, which has been mixed at the second incident surface 102 and the reflecting surface 103, as well as further mixing of the first light L1, which has been mixed at the first incident surface 101. However, at the exit surface 104, mixing occurs not only in the circumferential direction W but also in the radial direction R. The configuration and effects of this embodiment other than those described above are the same as those of the first embodiment.

[0067] <Fourth Embodiment> Figure 24 is a perspective view of the lens member according to this embodiment, seen from the opposite side of the light source. Figure 25A is a graph showing the cross-sectional shape of the emission surface, with the horizontal axis representing the position in the X direction and the vertical axis representing the position in the Z direction. Figure 25B is a graph showing the cross-sectional shape of the emission surface, with the horizontal axis representing the position in the Y direction and the vertical axis representing the position in the Z direction.

[0068] As shown in Figures 24, 25A, and 25B, in the lens member 140 of this embodiment, the shape of the XZ cross section of the exit surface 144 is a sinusoidal curve. Furthermore, the shape of the YZ cross section of the exit surface 144 is also a sinusoidal curve. Note that "shape is a sinusoidal curve" means that the design values ​​were determined along a sinusoidal curve, and errors in shape due to process errors and thermal deformation are within an acceptable range.

[0069] The point where the sine curve reaches its maximum value in the XZ cross-section shown in Figure 25A also reaches its maximum value in the YZ cross-section shown in Figure 25B, and the point where the sine curve reaches its minimum value in the XZ cross-section also reaches its minimum value in the YZ cross-section. The distance between the point where the sine curve reaches its maximum value on the exit surface 144 and the first incident surface 101 is greater than the distance between the point where the sine curve reaches its minimum value on the exit surface 144 and the first incident surface 101. In a top view, the points where the sine curve reaches its maximum value and the points where the sine curve reaches its minimum value are arranged in a staggered pattern.

[0070] According to this embodiment, similar to the third embodiment, light can be mixed at the emission surface 144. This reduces the need to provide a diffusion sheet on the emission surface 144 side of the lens member 140. As a result, the lighting device can be miniaturized. The configuration and effects of this embodiment other than those described above are the same as those of the first embodiment.

[0071] <Fifth Embodiment> Figure 26 is a top view showing the lens member according to this embodiment. Figure 27A is a graph showing a sine curve. Figure 27B is a perspective view showing the shape of the convex portion of the ejection surface. Figure 27C is a cross-sectional view taken along the XXVIIC plane shown in Figure 27B.

[0072] As shown in Figure 26, in the lens member 150 of this embodiment, a plurality of protrusions 151 are provided on the emission surface 154. The plurality of protrusions 151 are arranged in a matrix along the X and Y directions.

[0073] As shown in Figure 27A, we assume a region 157 enclosed by a part of the sine curve 152 that contains one point 155 where it takes a maximum value and two points 156 where it takes a minimum value, and a line segment 153 connecting the two points 156 where it takes a minimum value. As shown in Figures 27B and 27C, the shape of the convex portion 151 is the shape obtained by cutting out the inside of a square that is inscribed in a top view from a solid of revolution obtained by rotating the region 157 around a rotation axis extending in the Z direction.

[0074] According to this embodiment, light can be mixed at the emission surface 154, similar to the fourth embodiment. The configuration and effects of this embodiment other than those described above are the same as those of the fourth embodiment.

[0075] <Sixth Embodiment> Figure 28 is a perspective view of the lens member according to this embodiment, seen from the opposite side of the light source. As shown in Figure 28, the lens member 160 in this embodiment has a different arrangement of protrusions 151 compared to the lens member 150 in the fifth embodiment. On the exit surface 164 of the lens member 160, a plurality of protrusions 151 are arranged concentrically. The shape of the protrusions 151 is as described in the fifth embodiment.

[0076] According to this embodiment, by arranging the protrusions 151 in a concentric circle, the occurrence of grid-like unevenness on the illumination surface of the lighting device can be reduced. The configuration and effects of this embodiment other than those described above are the same as those of the fifth embodiment.

[0077] <Seventh Embodiment> Figure 29 is a top view showing a part of the lens member according to this embodiment. Figure 30A is a graph showing the shape of the ejection surface, with the horizontal axis representing the position in the radial direction R and the vertical axis representing the position in the Z direction. Figure 30B is a graph showing the shape of the ejection surface, with the horizontal axis representing the position in the circumferential direction W and the vertical axis representing the position in the Z direction.

[0078] As shown in Figures 29, 30A, and 30B, the lens member 180 according to this embodiment differs from the lens member 160 according to the sixth embodiment in that a plurality of annular regions 183 are provided on the emission surface 184. Each annular region 183 is arranged to include point 186 at each point 186 where the sine curve in the RZ cross section takes its minimum value. Therefore, the plurality of annular regions 183 are arranged concentrically around a first point 181 where the emission surface 184 intersects the optical axis 200C of the light source 200. Each annular region 183 is substantially flat in the Z direction. Therefore, the emission surface 184 has a flat cross-sectional shape along the circumferential direction W, including point 186.

[0079] On the other hand, the exit surface 184 includes point 185 where the sine curve in the RZ cross section takes its maximum value, and its cross-sectional shape along the circumferential direction W is a sine curve. Furthermore, the exit surface 184 is a sine curve in the RZ cross section that includes the first point 181 and the second point on the outer edge of the exit surface 184. The configuration and effects of this embodiment other than those described above are the same as those of the seventh embodiment.

[0080] <Eighth Embodiment> First, the design concept of the lens member 190 according to this embodiment will be explained. Figures 31A and 31B are perspective views illustrating the design concept of the lens component according to this embodiment.

[0081] As shown in Figures 31A and 31B, irregularities are formed on the exit surface 194 of the lens member 190 such that the cross section along the radial direction R is a sinusoidal curve. This creates a plurality of fin portions 501 arranged concentrically on the exit surface 194. Each fin portion 501 has an annular shape. Also, the height of the plurality of fin portions 501 is the same. At this stage, the WZ cross-sectional shape of the exit surface 194 along the circumferential direction W is flat at all positions along the radial direction R.

[0082] Next, multiple virtual cones 502 are assumed. These multiple cones 502 are then arranged periodically along the circumferential direction W so as to be interposed between multiple fin portions 501. At this time, the vertex 502a of the cone 502 is located at the first point 194a of the emission surface 194, that is, at the intersection of the emission surface 194 and the optical axis 200C of the light source 200, the central axis 502c of the cone 502 extends in the radial direction R, and the base surface 502b of the cone 502 is located outside the outer edge of the emission surface 194. In the inner region of the emission surface 194, the cone 502 does not reach the grooves between the fin portions 501, but in the outer region of the emission surface 194, it enters the grooves between the fin portions 501.

[0083] Next, the portion of the exit surface 194 that overlaps with the cone 502 is removed. The cone 502 is also removed. As a result, periodic recesses 503 are formed in the fin portion 501 along the circumferential direction. When viewed from the radial direction R, the shape of the recesses 503 is the lower part of a circular arc or a sinusoidal curve.

[0084] The shape of the ejection surface 194 designed in this manner will now be described. Figure 32 is a top view showing a lens member according to this embodiment. Figure 33 is a perspective view showing a part of the lens member according to this embodiment. Figure 34A is a graph showing the shape of the ejection surface along the XXXIVA line shown in Figure 33, with the horizontal axis representing the position in the radial direction R and the vertical axis representing the position in the Z direction. Figure 34B is a graph showing the shape of the ejection surface along the XXXIVB line shown in Figure 33, with the horizontal axis representing the position in the radial direction R and the vertical axis representing the position in the Z direction. Figure 35A is a graph showing the WZ cross-sectional shape of the emission surface, with the horizontal axis representing the position in the circumferential direction W and the vertical axis representing the position in the Z direction. Figure 35B is a graph showing the WZ cross-sectional shape of the emission surface, with the horizontal axis representing the position in the circumferential direction W and the vertical axis representing the position in the Z direction.

[0085] As shown in Figures 32 to 33, the exit surface 194 of the lens member 190 according to this embodiment has a structure that combines a structure along the radial direction R and a structure along the circumferential direction W. Multiple radial protrusions 191a extending radially from a first point 194a along the radial direction R are arranged radially on the exit surface 194, and the space between adjacent radial protrusions 191a is a radial recess 191b. The radial recess 191b corresponds to the hypothetical cone shape 502 described above. Therefore, the radial recess 191b becomes deeper as it moves from the first point 194a to the second point 194b. The second point 194b is located on the outer edge of the exit surface 194. The line XXXIVA shown in Figure 33 is located on the radial protrusion 191a, and the line XXXIVB is located on the radial recess 191b.

[0086] As shown in Figure 34A, the RZ cross-sectional shape of the radial convex portion 191a is a sine curve. That is, in the radial convex portion 191a, the shape of the RZ cross-section including the first point 194a and the second point 194b is a sine curve. The sine curve of the RZ cross-section of the radial convex portion 191a contains multiple points 195 that are local maxima. These multiple points 195 that are local maxima lie on the same virtual plane 505. Plane 505 is the XY plane. The exit surface 194 as a whole is located at or below plane 505.

[0087] As shown in Figure 34B, the RZ cross-sectional shape of the radial recess 191b is a straight line. The radial recess 191b is tangent to the virtual plane 505 at the first point 194a. The radial recess 191b is displaced downward as it moves away from the first point 194a.

[0088] As shown in Figure 35A, the exit surface 194 includes point 195, which is the maximum value of the sine curve of the RZ cross section, and in the WZ cross section along the circumferential direction W, circumferential straight sections 192a and circumferential recesses 192b are arranged alternately. The circumferential straight sections 192a are the parts that intersect with the radial convex sections 191a and correspond to the parts between the recesses 503 of the fin section 501 described above. The circumferential recesses 192b are the parts that intersect with the radial recesses 191b and correspond to the recesses 503 of the fin section 501 described above.

[0089] As described above, in the sine curve of a single RZ section, there are multiple points 195 that have a maximum value. Let one of these points 195 be the third point 195c and the other be the fourth point 195d. The third point 195c is a different point from the first point 194a. The third point 195c may coincide with the second point 194b, or it may be different. The fourth point 195d is located between the third point 195c and the first point 194a. That is, the fourth point 195d is located inside the exit surface 194 than the third point 195c.

[0090] In Figure 35A, the WZ cross section passing through the third point 195c is shown as curve 511, and the WZ cross section passing through the fourth point 195d is shown as curve 512. Curve 511 is located in the outer region of the exit surface 194, and curve 512 is located in the inner region of the exit surface 194.

[0091] As shown in Figure 35A, the WZ section (curve 511) passing through the third point 195c has a longer arrangement period of the circumferential straight section 192a and the circumferential recess 192b, and the circumferential recess 192b is deeper, compared to the WZ section (curve 512) passing through the fourth point 195d. For this reason, in the WZ section (curve 511) including the third point 195c and along the circumferential direction W, the third distance D3 in the Z direction between the third point 195c and the point 192c that is the minimum value within the circumferential recess 192b, i.e., in the direction in which the optical axis 200C extends, is greater than the fourth distance D4 in the Z direction between the fourth point 195d and the point 192d that is the minimum value within the circumferential recess 192b in the WZ section (curve 512) including the fourth point 195d and along the circumferential direction W. That is, D3 > D4.

[0092] In Figure 35B, among the WZ cross-sections along the circumferential direction W that include the radial recess 191b, the cross-section located next to curve 511 is shown as curve 513, and the cross-section located next to curve 512 is shown as curve 514. Curve 513 is located in the outer region of the exit surface 194, and curve 514 is located in the inner region of the exit surface 194.

[0093] As shown in Figure 35B, the WZ cross section along the circumferential direction W, which includes the radial recess 191b, has alternating circumferential straight sections 196a and circumferential recesses 196b in the outer region (curve 513) of the exit surface 194, and is substantially flat in the inner region (curve 514) of the exit surface 194.

[0094] According to this embodiment, the same optical effects as those of the seventh embodiment described above can be obtained. Furthermore, according to this embodiment, modeling during manufacturing is easier compared to the seventh embodiment. The configuration and effects of this embodiment other than those described above are the same as those of the seventh embodiment.

[0095] <Ninth Embodiment> This embodiment is an example of a lighting fixture that combines multiple lighting devices. Figure 36 is a top view showing a lighting fixture according to this embodiment.

[0096] As shown in Figure 36, the lighting fixture 1000 according to this embodiment includes four lighting devices 2 to 5. The lighting devices 2 to 5 are arranged on a common substrate 900. The lighting devices 2 to 5 are arranged in a line at equal intervals along the Y direction. The illumination positions of the four lighting devices 2 to 5 are substantially the same.

[0097] The configurations of each of the lighting devices 2 to 5 are, for example, the same as those of the first embodiment described above, or any of the second to eighth embodiments. However, they are not limited to these configurations. It is preferable that the configurations of the lighting devices 2 to 5 are the same as those of each other, but they may be different.

[0098] In this embodiment, an example will be described in which the configuration of the lighting devices 2 to 5 is the same as the second modified example of the first embodiment (see Figure 19). That is, each of the lighting devices 2 to 5 has a light source 220 and a lens member 100. The light source 220 has one light-emitting element 203 and a wavelength conversion member 205.

[0099] Illumination device 2 (first illumination device) includes a light source 220 (first light source) including a light-emitting element 203 (first light-emitting element), and a lens member 100 (first lens member) into which light from the light source 220 can be incident. Illumination device 3 (second illumination device) includes a light source 220 (second light source) including a light-emitting element 203 (second light-emitting element), and a lens member 100 (second lens member) into which light from the light source 220 can be incident. The configurations of illumination devices 4 and 5 are similar.

[0100] In a top view, the direction from the center 220c of the light source 220 of lighting device 2 towards the center 203c of the light-emitting element 203 is defined as the first direction V1. The direction from the center 220c of the light source 220 of lighting device 3 towards the center 203c of the light-emitting element 203 is defined as the second direction V2. The direction from the center 220c of the light source 220 of lighting device 4 towards the center 203c of the light-emitting element 203 is defined as the third direction V3. The direction from the center 220c of the light source 220 of lighting device 5 towards the center 203c of the light-emitting element 203 is defined as the fourth direction V4. The first direction V1, the second direction V2, the third direction V3, and the fourth direction V4 are all different from each other. For example, the first direction V1, the second direction V2, the third direction V3, and the fourth direction V4 are all 90° apart.

[0101] According to this embodiment, the lighting devices 2 to 5 cancel out color unevenness, thereby reducing color unevenness in the lighting fixture 1000 as a whole. The configuration and effects of this embodiment other than those described above are the same as those of the first embodiment.

[0102] <Example Test> In this test example, the lighting apparatus according to the first embodiment, the second embodiment, and the comparative example described above was assumed, and the mixing of light was calculated by performing a simulation. Figures 37A and 37B show the simulation method used in this test example. Figures 38A to 38C are graphs showing the simulation results in this test example, with the horizontal axis representing the position in the X direction and the vertical axis representing the position in the Y direction. Figure 38A shows a lighting device according to a comparative example, Figure 38B shows a lighting device according to a second embodiment, and Figure 38C shows a lighting device according to a first embodiment.

[0103] As shown in Figure 37A, the light emitted from the light source 200, which is emitted in a direction tilted 60° in the Y direction from the optical axis 200C in the YZ plane, is defined as the reference light L10. Then, a collection of light obtained by changing the emission direction within a range of ±15° or less from the reference light L10 in the YZ plane is assumed, and this is defined as the reference light band L11.

[0104] When the reference light band L11 enters the lens member 100 from the second incident surface 102 and reaches the reflective surface 103, the reference light band L11 is in contact with the reflective surface 103 at the line segment L11S. The reference light L10 is in contact with the reflective surface 103 at point L11P within the line segment L11S. Then, the reference light band L11 is reflected by the reflective surface 103 and exits from the exit surface 104.

[0105] As shown in Figure 37B, in this simulation, the reference light source L10 was kept constant, while the reference light band L11 was rotated around the reference light source L10. The rotation angles were set to 0°, 45°, and 90°. The position of the reference light band L11, which was reflected by the reflective surface 103 and emitted from the emission surface 104, when it reached the projection surface was calculated.

[0106] Figures 38A to 38C show the arrival positions of the reference light band L11 on the projection plane. As shown in Figure 38A, in the lighting device of the comparative example, the reference light band L11 reached the projection surface in a substantially straight line, and no mixing effect was observed.

[0107] As shown in Figure 38B, in the lighting device according to the second embodiment, the arrival position of the reference light band L11 on the projection surface changes by approximately ±1000 mm in the X direction, and a certain mixing effect was observed.

[0108] As shown in Figure 38C, in the lighting device according to the first embodiment, the arrival position of the reference light band L11 on the projection surface changes by approximately ±1500 mm in the X direction, and a significant mixing effect was observed.

[0109] The embodiments and their modifications described above are examples that embody the present invention, and the present invention is not limited to these embodiments and modifications. For example, the present invention is also included in the embodiments and modifications described above in which some components are added, deleted, or changed. Furthermore, the embodiments and modifications described above can be implemented in combination with each other.

[0110] The present invention includes the following embodiments.

[0111] (Note 1) A lens member into which light from a light source can be incident, The optical axes of the light source intersect, and a first incident surface is into which first light, which includes light emitted in the direction in which the optical axes extend, is incident. In a top view, the first incident surface surrounds the first incident surface and has first irregularities along the circumferential direction surrounding the optical axis, and a second incident surface is into which a second light, different from the first light, from the light source is incident, A reflective surface that surrounds the optical axis, has a second uneven surface along the circumferential direction, and totally reflects the light incident from the second incident surface, An emitting surface from which light reflected by the reflective surface and light incident from the first incident surface are emitted, A lens component equipped with the following features.

[0112] (Note 2) The lens member according to Appendix 1, wherein the number of protrusions arranged along the circumferential direction in the first irregularities of the second incident surface is 4 or more and 36 or less.

[0113] (Note 3) The lens member according to Appendix 2, wherein the number of protrusions arranged along the circumferential direction in the first irregularities of the second incident surface is 6 or more and 18 or less.

[0114] (Note 4) The lens member according to Appendix 3, wherein the number of protrusions arranged along the circumferential direction in the first irregularities of the second incident surface is 12.

[0115] (Note 5) A lens member according to any one of the appendices 1 to 4, wherein, in a cross section perpendicular to the optical axis, the first distance between the second incident surface and the reflective surface in a first straight line passing through the optical axis and the convex portion of the second unevenness is different from the second distance between the second incident surface and the reflective surface in a second straight line passing through the optical axis and the concave portion of the second unevenness.

[0116] (Note 6) The lens member described in Appendix 5, wherein the first distance is longer than the second distance.

[0117] (Note 7) The lens member according to Appendix 5 or 6, wherein the first straight line passes through the convex portion of the first unevenness, and the second straight line passes through the concave portion of the first unevenness.

[0118] (Note 8) The lens member according to Appendix 5 or 6, wherein the absolute value of the difference between the first distance and the second distance is 1% or more of the second distance.

[0119] (Note 9) The lens member described in Appendix 8, wherein the absolute value is 5% or more of the second distance.

[0120] (Note 10) The lens member according to any one of the appendices 5 to 9, wherein the curvature of the reflective surface in the first cross-section including the optical axis and the first straight line is greater than the curvature of the reflective surface in the second cross-section including the optical axis and the second straight line.

[0121] (Note 11) The lens member according to Appendix 10, wherein the curvature of the reflective surface in a cross section located between the first cross section and the second cross section, including the optical axis, is a value obtained by linear interpolation of the curvature in the first cross section and the curvature in the second cross section.

[0122] (Note 12) A lens member according to any one of the appendices 1 to 11, wherein light emitted from the light source, incident from the second incident surface, reflected at a first point on the line of intersection between the cross section perpendicular to the optical axis and the reflective surface, and emitted from the emission surface, intersects with light emitted from the light source, incident from the second incident surface, reflected at a second point on the line of intersection, and emitted from the emission surface.

[0123] (Note 13) The lens member according to any one of appendices 1 to 12, wherein the first incident surface protrudes toward the light source and has a third uneven surface along the circumferential direction.

[0124] (Note 14) The emission surface is a lens member according to any one of appendices 1 to 13, having a microlens array.

[0125] (Note 15) The lens member according to any one of the appendices 1 to 13, wherein the emission surface is a sine curve in a cross-section including a first point where the emission surface intersects the optical axis and a second point on the outer edge of the emission surface.

[0126] (Note 16) The lens member described in Appendix 15, wherein the emission surface includes the point of maximum value of the sine curve and, in a cross section along the circumferential direction, alternately arranged circumferential straight sections consisting of straight lines and circumferential recesses consisting of concave sections.

[0127] (Note 17) There are multiple points where the sine curve has a maximum value, and these points lie on the same plane. The aforementioned multiple points of local maximum value include a third point different from the first point, and a fourth point located between the third point and the first point. The lens member according to Appendix 16, wherein, in a cross-section including the third point and along the circumferential direction, the distance in the direction in which the optical axis extends between the third point and the point that is the minimum value within the circumferential recess is greater than the distance in the direction in which the optical axis extends between the fourth point and the point that is the minimum value within the circumferential recess in a cross-section including the fourth point and along the circumferential direction.

[0128] (Note 18) The aforementioned light source, A lens component described in any one of the appendices 1 to 17, A lighting device equipped with this.

[0129] (Note 19) The aforementioned light source is At least one light-emitting element, A wavelength conversion member that converts the peak wavelength of light emitted from the light-emitting element, It has, The lighting device according to Appendix 18, wherein, in a top view, the center of the wavelength conversion member and the centers of all the light-emitting elements do not overlap.

[0130] (Note 20) The light source has a plurality of light-emitting elements with mutually different peak wavelengths. The lighting device according to Appendix 18 or 19, wherein, in a top view, the center of the light source and the centers of all the light-emitting elements do not overlap.

[0131] (Note 21) First lighting device, The second lighting device, Equipped with, Older 1 lighting device, A first light source including a first light-emitting element, A first lens member described in any one of appendices 1 to 17, into which light from the first light source can be incident, It has, The second lighting device, A second light source including a second light-emitting element, A second lens member described in any one of appendices 1 to 17, into which light from the second light source can be incident, It has, In a top view, the first direction from the center of the first light source to the center of the first light-emitting element is different from the second direction from the center of the second light source to the center of the second light-emitting element. [Explanation of Symbols]

[0132] 1, 2, 3, 4, 5: Lighting devices 100: Lens component 101: 1st entrance plane 101A: 3rd unevenness 102:Second incidence plane 102A: 1st unevenness 103: Reflective surface 103A: 2nd unevenness 104: Ejection surface 105 :Area 106: Tsuba (guard) 107: Intersection line 120: Lens component 130: Lens component 131: Lens element 140: Lens component 144: Ejection surface 150: Lens component 151: Convex part 152 :Sine curve 153: Line segment 154: Ejection surface 157 :Area 160: Lens component 164: Exit surface 180: Lens component 181: 1st point 183: Ring region 184: Ejection surface 190: Lens component 191a: Radial protrusion 191b: Radial recess 192a: Circumferential straight section 192b: Circumferential recess 194: Exit surface 194a :1st point 194b: 2nd point 195c: 3rd point 195d: 4th point 196a: Circumferential straight section 196b: Circumferential recess 200: Light source 200C: Optical axis 201: Cabinet 202: Light-emitting element 202c :center 203: Light-emitting element 203c :center 204: Wavelength conversion component 205: Wavelength conversion component 205c :center 206: Translucent material 207: Lead 210 :Light source 210c:center 220 :Light source 220c:center 230 :Light source 230c: Center 501: Fin section 502: Cone 502a: Vertex 502b: Bottom 502c: Central axis 503: Recess 505: Plane 511, 512, 513, 514: curve 900: Circuit board 1000: Lighting fixtures B1: 1st cross section B2: 2nd cross section D1: First distance D2: 2nd distance D3: Third distance D4: 4th distance L1: 1st light L10: Reference light L11: Reference band L11P: The point where the reference light L10 touches the reflective surface 103. L11S: The line segment where the reference light band L11 is tangent to the reflective surface 103. L2, L2_1, L2_2: Second light La, Lb, Lc: Light P0: Focus point P1: 1st point P2: 2nd point R: Radial direction S1: 1st straight line S2: 2nd straight line V1: 1st direction V2 :Second direction V3: Third Direction V4: Fourth Direction W: Zhou Fangxiang θ: angle

Claims

1. A lens member into which light from a light source can be incident, The optical axes of the light source intersect, and a first incident surface is into which first light, including light emitted in the direction in which the optical axes extend, is incident. In a top view, the first incident surface surrounds the first incident surface and has first irregularities along the circumferential direction surrounding the optical axis, and the second incident surface is into which a second light, different from the first light, from the light source is incident. A reflective surface that surrounds the optical axis, has a second uneven surface along the circumferential direction, and totally reflects the light incident from the second incident surface, An emitting surface that emits light reflected by the reflective surface and light incident from the first incident surface, A lens component equipped with the following features.

2. The lens member according to claim 1, wherein the number of protrusions arranged along the circumferential direction in the first irregularities of the second incident surface is 4 or more and 36 or less.

3. The lens member according to claim 2, wherein the number of protrusions arranged along the circumferential direction in the first irregularities of the second incident surface is 6 or more and 18 or less.

4. The lens member according to claim 3, wherein the number of protrusions arranged along the circumferential direction in the first irregularities of the second incident surface is 12.

5. The lens member according to claim 1, wherein, in a cross-section perpendicular to the optical axis, the first distance between the second incident surface and the reflective surface in a first straight line passing through the optical axis and the convex portion of the second unevenness is different from the second distance between the second incident surface and the reflective surface in a second straight line passing through the optical axis and the concave portion of the second unevenness.

6. The lens member according to claim 5, wherein the first distance is longer than the second distance.

7. The lens member according to claim 5, wherein the first straight line passes through the convex portion of the first unevenness, and the second straight line passes through the concave portion of the first unevenness.

8. The lens member according to claim 5, wherein the absolute value of the difference between the first distance and the second distance is 1% or more of the second distance.

9. The lens member according to claim 8, wherein the absolute value is 5% or more of the second distance.

10. The lens member according to claim 5, wherein the curvature of the reflective surface in the first cross-section including the optical axis and the first straight line is greater than the curvature of the reflective surface in the second cross-section including the optical axis and the second straight line.

11. The lens member according to claim 10, wherein the curvature of the reflective surface in a cross section located between the first cross section and the second cross section, including the optical axis, is a value obtained by linear interpolation of the curvature in the first cross section and the curvature in the second cross section.

12. The lens member according to claim 1, wherein light emitted from the light source, incident on the second incident surface, reflected at a first point on the line of intersection between the cross section perpendicular to the optical axis and the reflective surface, and emitted from the emission surface, intersects with light emitted from the light source, incident on the second incident surface, reflected at a second point on the line of intersection, and emitted from the emission surface.

13. The lens member according to claim 1, wherein the first incident surface protrudes toward the light source and has a third uneven surface along the circumferential direction.

14. The lens member according to claim 1, wherein the emission surface has a microlens array.

15. The lens member according to claim 1, wherein the emission surface is a sinusoidal curve in a cross-section including a first point where the emission surface intersects the optical axis and a second point on the outer edge of the emission surface.

16. The lens member according to claim 15, wherein the emission surface includes a point that is the maximum value of the sine curve and, in a cross section along the circumferential direction, a circumferential straight portion consisting of a straight line and a circumferential recess consisting of a concave shape are arranged alternately.

17. There are multiple points where the sine curve has a maximum value, and these points lie on the same plane. The aforementioned multiple points of local maximum value include a third point different from the first point, and a fourth point located between the third point and the first point. The lens member according to claim 16, wherein, in a cross-section including the third point and along the circumferential direction, the distance in the direction in which the optical axis extends between the third point and the point that is the minimum value within the circumferential recess is greater than the distance in the direction in which the optical axis extends between the fourth point and the point that is the minimum value within the circumferential recess in a cross-section including the fourth point and along the circumferential direction.

18. The aforementioned light source, A lens member according to any one of claims 1 to 17, A lighting device equipped with this.

19. The aforementioned light source is At least one light-emitting element, A wavelength conversion member that converts the peak wavelength of light emitted from the light-emitting element, It has, The lighting device according to claim 18, wherein, in a top view, the center of the wavelength conversion member and the centers of all the light-emitting elements do not overlap.

20. The light source has a plurality of light-emitting elements with mutually different peak wavelengths. The lighting device according to claim 18, wherein, in a top view, the center of the light source and the centers of all the light-emitting elements do not overlap.

21. First lighting device and The second lighting device, Equipped with, The first lighting device is A first light source including a first light-emitting element, A first lens member according to any one of claims 1 to 17, into which light from the first light source can be incident, It has, The second lighting device, A second light source including a second light-emitting element, A second lens member according to any one of claims 1 to 17, into which light from the second light source can be incident, It has, In a top view, the first direction from the center of the first light source toward the center of the first light-emitting element is different from the second direction from the center of the second light source toward the center of the second light-emitting element.

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