JP7065316B2 - Lighting equipment and lenses - Google Patents

Description

The present disclosure relates to lighting equipment. The present disclosure also relates to lenses used in lighting devices.

Conventionally, as a lighting device, there is one described in Patent Document 1. The illuminator comprises a housing, a light source disposed within the housing, and a Fresnel lens disposed within the housing. The Fresnel lens has a plurality of Fresnels having a sawtooth shape in a cross section including the central axis from the radial center side to the edge side on the incident side. The Fresnel lens is arranged below (front side) the light source in the housing, receives the light from the light source, and projects the light into the projection region. The housing has a tubular member below the Fresnel lens. The tubular member includes an incident opening, an exit opening, and a truncated cone-shaped inner peripheral surface located between them. The light from the Fresnel lens enters the incident opening and is emitted from the exit opening. Further, the inner peripheral surface of the tubular member reflects the light that has reached the inner peripheral surface toward the projection region side. The lighting device realizes diffused light distribution that widens the 1/2 beam angle by totally reflecting the light with Fresnel.

Japanese Unexamined Patent Publication No. 2017-50188

In specifications where diffused light is desired, it is necessary to spread and diffuse the light from the light source. However, if the light from the light source is excessively diffused, a large amount of light is reflected on the inner peripheral surface of the tubular member. Then, when a person looks up at the lighting device, a large amount of reflected light is incident on the eyes, and the person tends to feel glare.

Therefore, an object of the present disclosure is to provide a lighting device and a lens that can appropriately spread the light from a light source, appropriately illuminate a set irradiation area, and suppress glare when a person looks up. To do.

In order to solve the above problems, the lighting device according to the present disclosure includes a light source arranged in a housing, an incident portion in which light from the light source is incident, and a lens having an exit portion for emitting light. The emission surface on the light emission side of the light source has a concave surface portion located at the central portion in the radial direction and a convex surface portion located between the concave surface portion and the peripheral edge thereof.

Further, the lens according to the present disclosure is a lens that is built in a lighting device and transmits light from the light source of the lighting device, and includes an incident portion in which light from the light source is incident and an exit portion that emits light. The light emitting surface on the light emitting side has a concave surface portion located at the central portion in the radial direction and a convex surface portion located between the concave surface portion and the peripheral edge thereof.

According to the lighting device and the lens according to the present disclosure, the light from the light source can be appropriately spread, the set irradiation area can be appropriately illuminated, and the glare when a person looks up can be suppressed.

It is a perspective view of the lighting apparatus which concerns on one Embodiment of this disclosure. It is an exploded perspective view of the main part of a lighting device. It is sectional drawing of the area including a lens when the illuminating device is cut in the plane including the central axis of the auxiliary reflection member. It is a schematic cross-sectional view when the lens is cut in the plane including the central axis thereof. It is a perspective view when the lens is seen from the lower side. It is a perspective view when the lens is seen from the upper side. FIG. 3 is an enlarged cross-sectional view of the vicinity of the central portion of the lens in FIG. FIG. 3 is an enlarged cross-sectional view of the vicinity of the peripheral edge of the lens in FIG.

Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. When a plurality of embodiments and modifications are included in the following, it is assumed from the beginning that a new embodiment is constructed by appropriately combining the characteristic portions thereof. Further, in the following examples, the same components are designated by the same reference numerals in the drawings, and duplicate description will be omitted. Further, the plurality of drawings include schematic views, and the dimensional ratios of the vertical, horizontal, and height of each member do not always match between different drawings. Further, in the present specification, the lower side refers to the light emitting side in the height direction, and the upper side means the side opposite to the light emitting side in the height direction. More specifically, in the following description, when words related to the vertical direction, for example, the lower side, the upper side, the horizontal direction, etc. are used, those words are such that the light emitted from the lighting device 1 illuminates the lower side in the vertical direction. It is expressed in a state where the optical axes of the emitted light are aligned in the vertical direction. That is, in this embodiment, the case where the lighting device 1 is arranged so that the height direction coincides with the vertical direction will be described as an example. The lighting device 1 may be used in a state where the height direction coincides with the direction of inclination in the vertical direction.

FIG. 1 is a perspective view of a lighting device 1 according to an embodiment of the present disclosure. The lighting device 1 is an embedded downlight, which is embedded in the ceiling of a building such as a hall and illuminates the lower part. As shown in FIG. 1, the lighting device 1 includes a housing 5 and a mounting portion 90, and the housing 5 has a base 10 and a frame body 80. The base 10 is an outer member of the lighting device 1 and has a bottomed cylindrical portion 11. The base 10 functions as a mounting base for mounting the light source 20 (see FIG. 2) in the bottomed cylindrical portion 11. Further, the base 10 has a plurality of fins 12 protruding upward. The base 10 also functions as a heat sink that dissipates the heat generated by the light source 20, and in particular, the fins 12 dissipate the heat from the light source 20 to the outside air. Therefore, it is preferable that the base 10 is made of a material having high thermal conductivity such as a metal material. The bottomed cylindrical portion 11 and the fin 12 may be integrally molded by aluminum die casting or the like, or may be integrated by joining. In this case, for example, the bottomed cylindrical portion and the fin may be connected by inserting the protrusion provided in the bottomed cylindrical portion into the hole provided in the fin and then plastically deforming the protrusion. The base does not have to have fins.

The frame 80 is formed of, for example, a metal material such as aluminum or a resin material such as polybutylene terephthalate. The frame body 80 is a substantially cylindrical member, and the light from the light source 20 passes through the inside of the frame body 80 and is emitted to the outside of the lighting device 1. The outer diameter of the frame 80 is about the same as the outer diameter of the base 10. The mounting portion 90 has three mounting springs 91. The three mounting springs 91 are mounted on the frame body 80, and are arranged, for example, on the outside of the frame body 80 at substantially equal intervals in the circumferential direction of the frame body 80. Each mounting spring 91 extends in a direction substantially orthogonal to the height direction in a state before being fixed to the embedded hole in the ceiling. The mounting spring 91 is composed of, for example, a long metal plate and has a leaf spring structure. The mounting spring 91 abuts around the embedding hole and applies a radial outward force to the inner peripheral surface of the embedding hole and the like. The lighting device 1 is fixed to the embedded hole by receiving the reaction force of the radial outer force from the inner peripheral surface or the like. Two or four or more mounting springs 91 may be provided. Further, the structure of the mounting portion is not limited to the structure shown in FIG. 1, and the mounting portion may not have a mounting spring. The structure of the mounting portion may be any structure as long as the lighting main body, which is a portion of the lighting device excluding the mounting portion, can be fixed to the ceiling.

FIG. 2 is an exploded perspective view of a main part of the lighting device 1. Next, with reference to FIG. 2, the basic structure of the lighting device 1 and the fixed structure of the main member included in the lighting device 1 will be briefly described. As shown in FIG. 2, the lighting device 1 includes a light source 20, a light source holder 30, a reflection member 40, a lens 50, and an auxiliary reflection member 70 in addition to the base 10 and the frame 80. The reflective member 40 and the auxiliary reflective member 70 are included in the housing 5 (see FIG. 1).

The light source 20 has a substrate 21 and a light emitting unit 22. The substrate 21 has a substantially square shape in a plan view, and the light emitting portion 22 has a disk-like shape. The light emitting unit 22 is arranged substantially in the center of the lower surface (mounting surface) of the substrate 21. The light source 20 has, for example, a COB (Chip On Board) structure, and the light emitting unit 22 includes a plurality of LEDs (light emitting diodes) mounted on the substrate 21 and a sealing member for sealing the plurality of LEDs. ..

The substrate 21 is composed of, for example, a ceramic substrate, a resin substrate, a metal base substrate, or the like. Although not described in detail, a pair of electrode terminals and an LED drive circuit having a predetermined pattern are formed on the substrate 21. Further, the LED drive circuit is a circuit for driving the LEDs, and the LEDs are electrically connected to each other. DC power from the outside is supplied to the LED drive circuit via a pair of electrode terminals, and a current is passed through the LED drive circuit to cause the LED to emit light.

The LED is composed of, for example, a bare chip that emits visible light of a single color, and is composed of a blue LED chip that emits blue light when energized. The plurality of LEDs are arranged in a matrix on the substrate 21, for example. Only one LED may be mounted on the board. The sealing member is made of, for example, a translucent resin and contains a fluorescent substance. The phosphor serves to wavelength-convert the light from the LED. The sealing member is composed of, for example, a phosphor-containing resin in which fluorescent particles are dispersed in a silicone resin. When the light source 20 is a blue LED chip that emits white light and the LED emits blue light, the phosphor particles are composed of, for example, a YAG-based yellow phosphor. As the sealing member, all the LEDs may be collectively sealed, a plurality of LEDs may be sealed in a line for each row, or each LED may be individually sealed one by one.

The light source holder 30 includes a light source accommodating chamber having a rectangular opening corresponding to the substrate 21 on the upper side in a plan view, and the light source 20 is accommodated in the light source accommodating chamber with the light emitting unit 22 facing downward. The lighting device 1 further includes a substrate locking member 31, and the lower side of the light source holder 30 so that the substrate receiving portion formed of a part of the substrate locking member 31 overlaps the light source accommodating chamber when viewed from the height direction. Placed in. The light source accommodating chamber has a through hole at a position overlapping the light source 20 when viewed from the height direction, and the light from the light source 20 is emitted downward through the lower opening of the through hole. A part of the peripheral portion of the lower surface of the substrate 21 is supported by the upper surface of the substrate receiving portion. Bolts (not shown) are tightened in the order of the substrate locking member 31, the light source holder 30, and the main surface 14 of the base 10, from the lower side, and as a result, the substrate locking member 31, the light source holder 30, and the light source 20 are tightened in this order. Is attached to the base 10.

The reflective member 40 is an annular member, and its inner peripheral surface reflects the light emitted from the light source 20 to guide the light from the light source 20 to the lens 50 side in a state where stray light is not substantially generated, and from the light source 20. Controls the light distribution of the light source. The reflective member 40 is formed of, for example, a white resin material. Polybutylene terephthalate or the like can be preferably used as the resin material constituting the reflective member 40. The reflective member 40 may be formed of a metal material such as aluminum, or may have a metal film such as aluminum formed on the inner surface of the resin molded product. The reflective member 40 has a plurality of lens locking portions 41 arranged on the outer peripheral side at intervals in the circumferential direction.

The lens 50 is a translucent member having translucency, and transmits light from the reflecting member 40. The lens 50 is made of a translucent material having translucency, and is preferably formed of, for example, an acrylic, a silicone-based resin material, a transparent resin material such as polycarbonate, or a glass material. The lens 50 covers the lower opening of the reflective member 40, so that the lower side of the light source 20 is covered by the lens 50 and the light source 20 is protected. The lens 50 includes a plurality of engaging claws 51 projecting outward in the warp direction on the outer peripheral side. The plurality of engaging claws 51 are arranged at intervals in the circumferential direction. Each engaging claw 51 is fixed to the corresponding lens locking portion 41 in the reflective member 40 by a snap fit, and as a result, the lens 50 is attached to the reflective member 40.

The auxiliary reflection member 70 is arranged inside the frame body 80. The auxiliary reflection member 70 is an annular frame made of a thin metal plate such as aluminum, and has a cup-shaped portion 76 whose inner diameter gradually increases toward the lower side. Almost all of the cup-shaped portions 76 are arranged under the lens 50. The inner peripheral surface of the cup-shaped portion 76 reflects the light emitted from the lens 50 and guides the light to the irradiation region. The auxiliary reflective member 70 has a plurality of engaging claws 77 arranged at intervals in the circumferential direction and extending radially outward at the upper end portion.

Although not shown, the frame 80 has an annular flange portion that extends radially inward at the upper end portion, and the flange portion is provided with a plurality of engaging recesses arranged at intervals in the circumferential direction. .. By engaging the engaging claw 77 of the auxiliary reflecting member 70 with the engaging recess of the frame body 80, the auxiliary reflecting member 70 is positioned with respect to the frame body 80.

The illuminating device 1 further includes a plurality of bolts 8 (see also FIG. 1). The bolt 8 is used to integrate the base 10, the reflective member 40, and the frame 80. Specifically, each of the flange portion of the base 10, the reflective member 40, and the frame body 80 has a plurality of bolt fastening holes that overlap each other when viewed from the height direction. With reference to FIGS. 1 and 2, bolts 8 are fastened to the screw holes of the reflective member 40 and the frame 80 from the upper surface 19 (see FIG. 1) on which the fins 12 extend on the base 10. As a result, the base 10, the reflective member 40, and the frame 80 are integrally fastened, and the main part of the lighting device 1 is assembled.

Next, the light distribution in the lens 50 and the lens structure capable of realizing the light distribution will be described. FIG. 3 is a cross-sectional view of a region including the lens 50 when the lighting device 1 is cut in a plane including the central axis of the auxiliary reflection member 70, and FIG. 4 is a cross-sectional view of the lens 50 cut in a plane including the central axis thereof. It is a schematic cross-sectional view at the time of. Further, FIG. 5 is a perspective view of the lens 50 when viewed from below, and FIG. 6 is a perspective view of the lens 50 when viewed from above. Further, FIG. 7 is an enlarged cross-sectional view of the vicinity of the central portion of the lens 50 in FIG. 3, and FIG. 8 is an enlarged cross-sectional view of the vicinity of the peripheral portion of the lens 50 in FIG. In FIGS. 5 and 6, the engaging claw 51, which has little to do with the light distribution function of the lens 50, is not shown.

As shown in FIGS. 3 and 4, the lens 50 has an incident portion 52 into which light from a light source is incident and an emitting portion 53 in which light is emitted. Further, the emission surface 56 on the light emitting side of the lens 50 includes a concave surface portion 54 provided in the central portion in the radial direction and a convex surface portion 55 provided between the concave surface portion 54 and the peripheral edge thereof, and the convex surface portion 55 includes a convex surface portion 55. It is continuously and smoothly connected to the concave surface portion 54.

With reference to FIG. 5, the concave surface portion 54 is composed of a concave surface having a substantially circular edge in a plan view, and the convex surface portion 55 has an annular ridge-shaped shape that is smoothly connected to the outer peripheral edge portion of the concave surface portion 54. As shown in FIG. 4, an annular flat surface portion 57 is provided on the radial outer side of the convex surface portion 55 on the exit surface 56. The flat surface portion 57 is smoothly connected to the radial outer end portion of the annular convex surface portion 55, and spreads in a direction substantially perpendicular to the central axis of the concave surface portion 54.

As shown in FIGS. 4 and 6, the lens 50 has a flat surface portion 58 having a circular edge at the radial center portion on the light incident side, and Fresnel 59 is provided at the peripheral portion of the annular shape on the radial outer side thereof. Have. The Fresnel 59 has a sawtooth shape in a cross section including the central axis of the lens 50 (corresponding to the central axis of the concave portion 54), and the sawtooth teeth project upward in the height direction. As shown in FIG. 4, the concave portion 54 is preferably provided inward in the radial direction from the radial inward end of the Fresnel 59 (the radial position is indicated by a), and is viewed from the height direction. At times, it is preferable that the Fresnel 59 does not overlap the concave surface portion 54. Further, when the convex surface portion 55 and the flat surface portion 57 are connected around a position overlapping in the height direction with the tip of the Fresnel 59 (the radial position is indicated by b) located most radially outward on the emission surface 56. preferable.

In the cross section shown in FIG. 3, the light-shielding angle θ is a straight line 72 connecting one end 75 of the lower opening of the auxiliary reflection member 70 and the end 63 of the lower surface 62 of the lens 50 opposite to the one end 75 side, and auxiliary reflection. It is defined as the angle formed by the straight line 73 drawn by the lower opening of the member 70. The shading angle θ may be any value, but is preferably 5 ° or more and 40 ° or less, more preferably 10 ° or more and 30 ° or less, and most preferably 13 ° or more and 20 ° or less.

As described above, the lighting device 1 includes a light source 20 arranged in the housing 5, an incident portion 52 in which the light from the light source 20 is incident, and a lens 50 having an emitting portion 53 that emits the light. The emission surface 56 on the light emission side of the lens 50 has a concave surface portion 54 located at the central portion in the radial direction, and a convex surface portion 55 located between the concave surface portion 54 and the peripheral edge thereof.

According to this configuration, the emission surface 56 on the light emission side of the lens 50 has a concave surface portion 54 at the center portion in the radial direction. Therefore, the diameter of the light emitted from the light source 20 and reaching the concave portion 54, such as the light 64 shown by the alternate long and short dash line in FIGS. 3 and 7, and the light 65 shown by the alternate long and short dash line in FIG. It can be bent outward in the direction. Therefore, since the light distribution angle can be increased at the concave surface portion 54 and the light from the light source 20 can be appropriately spread, an appropriate diffused light can be generated and the set irradiation region can be appropriately illuminated.

Further, since the light from the light source 20 can be appropriately spread by the concave surface portion 54 located in the central portion, the luminous intensity directly under the irradiation light can be reduced. As a result, it is possible to suppress the glare of the central portion of the lighting device 1 when a person looks up at the lighting device 1.

Further, the exit surface 56 has a convex portion 55 between the concave portion 54 and the peripheral edge. Therefore, as in the case of the light 67 shown by the solid line in FIGS. 3 and 8, the traveling direction of the light emitted from the light source 20 and reaching the convex surface portion 55 is the case where the concave surface portion is formed instead of the convex surface portion 55. By comparison, the convex surface portion 55 can be changed inward in the radial direction. Therefore, as compared with the case where the concave surface portion is formed instead of the convex surface portion 55, it is possible to suppress the light reaching the outer peripheral side of the exit surface 56 from diffusing to the outside, and the reflection surface 79 of the auxiliary reflection member ( (See FIG. 3) can be suppressed. As a result, the amount of light reflected by the reflecting surface 79 can be reduced, so that when a person looks up at the lighting device 1, the reflected light from the reflecting surface 79 can be suppressed from being incident on the eyes, and the person is dazzled. It becomes difficult to feel.

Further, on the light incident side of the lens 50, a flat surface portion 58 is provided in the central portion in the radial direction, while a Fresnel 59 having a sawtooth-like shape in a cross section including the central axis is provided in the peripheral portion of the annular shape. May be good.

When a diffused light distribution having a relatively large 1/2 beam angle is desired, the illuminating device often provides a lens with a frennel that totally reflects the light in order to realize such a diffused light distribution. However, if Fresnel is formed up to the radial center on the light incident side, the light totally reflected by Fresnel inward in the radial direction increases and diffuses outward in the radial direction, as shown by the light 68 shown by the dotted line in FIG. The amount of light that intersects with the light (for example, the light as shown by 64,65,67) increases. The light 68 that intersects with such other light contributes to increasing the brightness especially in the central portion of the illuminating device to an unnecessary value, and the amount of light rays that come toward the line of sight when looking up at the illuminating device. In particular, it causes glare when looking up at the lighting device at an elevation angle of about 30 °.

On the other hand, according to the above configuration, the Fresnel 59 is provided only on the peripheral portion of the ring on the light incident side, and is not provided on the radial center portion on the light incident side. Therefore, the Fresnel 59 located on the outer peripheral side can pick up the peripheral light, and not only can the illumination light having an appropriate brightness be realized, but also the crossed light (dotted line) that intersects with other light near the center of the lens in the emitting side region. The light 68) as shown can be reduced. As a result, it is possible to suppress the amount of light rays coming toward the line of sight when looking up near the center of the lighting device, and it is possible to effectively suppress the maximum brightness of the light when looking up at the lighting device, especially at an elevation angle of about 30 °. , The glare can be effectively suppressed.

Further, as described above, the luminous intensity directly under the irradiation light can be reduced by the concave surface portion 54 in the central portion on the emission side. Therefore, due to the synergistic effect of the reduction of the crossed light due to the formation position of the Fresnel 59 and the reduction of the direct light intensity due to the formation of the concave surface portion 54, the glare when looking up near the central portion of the lighting device can be greatly suppressed, and it is beautiful and comfortable. A good illumination light can be realized.

Further, the light-shielding angle θ that makes the lens 50 invisible due to being blocked by the housing 5 may be 5 ° or more and 40 ° or less.

According to the above configuration, since the light blocking angle θ is 40 ° or less, the irradiation area by the lighting device 1 is unlikely to be narrowed, and it is easy to realize an appropriate diffused light distribution. Further, since the light blocking angle θ is 5 ° or more, the emission side region of the lens 50 can be appropriately covered with the housing 5, and the light projected from the lens 50 can be suppressed from directly entering the eyes. Therefore, the glare of the illumination light can be suppressed from the aspect of the arrangement of the housing 5.

Further, the concave surface portion 54 and the convex surface portion 55 may be smoothly connected.

According to the above configuration, there is no luminance unevenness caused by the corner portion as compared with the case where the corner portion is generated at the connection portion between the concave surface portion and the convex surface portion. Therefore, it is easy to realize the desired light distribution control, and it is easy to generate beautiful illumination light.

Further, the lens 50 is built in the lighting device 1 and transmits light from the light source 20 of the lighting device 1. Further, the lens 50 includes an incident portion 52 into which the light from the light source 20 is incident, and an emitting portion 53 for emitting the light. Further, the emission surface 56 on the light emission side of the lens 50 has a concave surface portion 54 located at the central portion in the radial direction and a convex surface portion 55 located between the concave surface portion 54 and the peripheral edge.

According to this configuration, the light from the light source 20 of the lighting device 1 can be appropriately diffused, and the glare when a person looks up can be suppressed.

The present disclosure is not limited to the above-described embodiment and its modifications, and various improvements and changes can be made within the scope of the claims of the present application and the equivalent scope thereof.

For example, in the above embodiment, the LED is adopted as the light emitting element, but the light emitting element may be a semiconductor laser element, and even if the phosphor is irradiated with the laser light from the semiconductor laser element, the illumination light is generated. good. Further, the light emitting unit of the light source may be configured by using a light emitting unit other than the semiconductor light emitting element, for example, an incandescent light bulb or the like.

Further, a case where the flat surface portion 58 is provided at the center portion in the radial direction on the light incident side of the lens 50 has been described. However, it is not necessary to provide a flat surface portion in the radial center portion on the light incident side of the lens, and for example, a frennel may be provided in the radial center portion on the light incident side of the lens instead of the flat surface portion. Further, a case where the concave surface portion 54 and the convex surface portion 55 are smoothly connected has been described. However, the connecting portion between the concave portion and the convex portion may include a corner portion. Even in these cases, the light emitting surface on the light emitting side of the lens includes a concave surface portion located in the central portion in the radial direction and a convex surface portion located between the concave surface portion and the peripheral edge thereof. The light from the light can be spread appropriately, and the glare when a person looks up can be suppressed.

Further, the case where the lighting device 1 is an embedded light has been described. However, the lighting device may be a downlight suspended from a rail or a ceiling. Alternatively, the illuminating device does not have to be a downlight. Further, the components of the lighting device are not limited to the above-mentioned components, and for example, one or more components may be deleted from the above-mentioned components, and conversely, one or more components may be added to the above-mentioned components. You may add it. Further, the fixed structure of each configuration is not limited to the fixed structure described above, and any fixed structure may be adopted. In short, the illuminating device of the present disclosure may include a light source arranged in a housing, an incident portion in which light from the light source is incident, and a lens having an exit portion for emitting light. Then, the emission surface on the light emission side of the lens may include a concave surface portion located at the central portion in the radial direction and a convex surface portion located between the concave surface portion and the peripheral edge thereof.

1 Lighting device, 5 housing, 20 light source, 50 lens, 52 incident part, 53 exit part, 54 concave part, 55 convex part, 56 exit surface, 58 flat part, 59 Fresnel, θ shading angle.

Claims (4)

The light source placed inside the housing and
A lens having an incident portion in which light from the light source is incident and an exit portion in which light is emitted.
Equipped with
The emission surface of the lens on the light emission side has a concave surface portion located at the center portion in the radial direction and a convex surface portion located between the concave surface portion and the peripheral edge thereof .
On the light incident side of the lens, a flat surface portion is provided in the central portion in the radial direction, while a fresnel having a sawtooth-like shape in a cross section including the central axis is provided in the peripheral portion of the annular shape.
When viewed from the height direction, the Fresnel does not overlap the concave surface portion, and the Fresnel lens does not overlap with the concave surface portion.
The radial outer end of the convex portion is located inward in the radial direction with respect to the Fresnel located in the outermost direction in the radial direction and is adjacent to the Fresnel located in the outermost direction. A lighting device located outward in the radial direction from a position where the tip of the Fresnel overlaps in the height direction . The lighting device according to claim 1 , wherein the light-shielding angle at which the lens becomes invisible due to being blocked by the housing is 5 ° or more and 40 ° or less. The lighting device according to claim 1 or 2 , wherein the concave surface portion and the convex surface portion are smoothly connected to each other. A lens that is built into a lighting device and transmits light from the light source of the lighting device.
It is equipped with an incident part where light from a light source is incident and an exit part which emits light.
The emission surface on the light emitting side has a concave surface portion located at the central portion in the radial direction and a convex surface portion located between the concave surface portion and the peripheral edge thereof .
On the light incident side of the lens, a flat surface portion is provided in the central portion in the radial direction, while a fresnel having a sawtooth-like shape in a cross section including the central axis is provided in the peripheral portion of the annular shape.
When viewed from the height direction, the Fresnel does not overlap the concave surface portion, and the Fresnel lens does not overlap with the concave surface portion.
The radial outer end of the convex portion is located inward in the radial direction with respect to the Fresnel located in the outermost direction in the radial direction and is adjacent to the Fresnel located in the outermost direction. A lens located outward in the radial direction from a position where it overlaps the tip of the Fresnel in the height direction .

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