JP2022126338A - Lens for lighting and lighting fixture - Google Patents

Abstract

To obtain an excellent uniformity ratio of illuminance while suppressing the glare.SOLUTION: There is provided a lens for lighting that is provided to a lighting fixture lighting up a road surface of a road and controls light of a light emitting element that the lighting fixture comprises to form laterally long symmetrical light distribution extending in the traffic direction of the road, and the lens for lighting comprises a convex emission surface 22 from which the light of the light emitting element is emitted and an incidence surface 24 which covers the light emitting element and is concave to the side of the emission surface 22, wherein the emission surface 22 has sag parts 50, including convex parts inside, at both shoulder parts 22A in the traffic direction.SELECTED DRAWING: Figure 4

Description

The present invention relates to lighting lenses and lighting fixtures.

In order to reduce the number of lighting fixtures to be installed by widening the installation interval (span) of lighting fixtures that illuminate the road surface, wide-span fixtures are known that extend the irradiation range of the road surface in the direction of traffic to a greater distance. (See Patent Document 1, for example).

By the way, in road lighting, there has been a problem of "glare" in which pedestrians and drivers feel glare when directly looking at the light emitted from lighting fixtures. In particular, glare is a particular problem with wide-span lighting fixtures because the longer the installation interval, the smaller the elevation angle when the lighting fixture is viewed by the driver of the vehicle.
Regarding glare, it is known that light in the range of 75 degrees or more in the vertical angle on a sine isoluminous curve defined as 0 degrees directly under the lighting fixture and 90 degrees in the horizontal direction (for example, , Non-Patent Document 1). In addition, as a result of an experiment comparing a cut-off type lighting fixture that completely cuts off light with a vertical angle of 75 degrees or more and a non-cut-off type lighting fixture that does not consider glare, more than 80% of the subjects were cut off. There is also a case where the answer was that the glare was reduced by the shape fixture (for example, see Non-Patent Document 2).

JP 2011-187303 A

Tatsuya Saito, Masanao Serita, "Calculation of glare", Journal of the Illuminating Engineering Institute of Japan, The Illuminating Engineering Institute of Japan, 1964, Vol. 48, No. 10, p. 498-504 Tatsuya Saito, "Highway Lighting", Journal of the Institute of Electrical Engineers of Japan, The Institute of Electrical Engineers of Japan, 1964, Vol. 84, No. 905, p. 167-176

Road lighting WHEREIN: One of the important performance indexes is the uniformity of road surface brightness.
However, when comparing the above-mentioned cut-off type lighting fixtures and the above-mentioned non-cut-off type lighting fixtures, the non-cut-off type lighting fixtures are superior in terms of uniformity, and it is difficult to obtain the specified degree of uniformity while suppressing glare. Met.

SUMMARY OF THE INVENTION An object of the present invention is to provide a lighting lens and a lighting fixture that can obtain good uniformity while suppressing glare.

The present invention provides a lighting lens that is provided in a lighting fixture that illuminates a road surface, controls light from a light-emitting element included in the lighting fixture, and forms a laterally elongated symmetrical light distribution that extends in the traffic direction of the road. , a convex emission surface from which the light of the light emitting element is emitted, and an incidence surface that covers the light emitting element and is recessed toward the side of the emission surface, the emission surface being provided on both shoulders in the traffic direction, A sag portion including a convex portion is formed inside.

In the illumination lens according to the present invention, the sag portion has a first sag portion and a second sag portion respectively closer to and farther from the optical center of the lens than the convex portion, and the first sag portion The bottom surface curvature is larger than that of the second sag portion.

In the illumination lens according to the present invention, the change in the angle of the outer shape of the sag portion with respect to the light source optical axis is continuously changed in the cross section along the traffic direction of the road.

In the illumination lens according to the present invention, the sag portion has an inclination angle of 40 degrees from the light source optical axis with the center of the light emitting element as a base point in a cross section including the light source optical axis and along the traffic direction of the road. and 75 degrees.

In the illumination lens according to the present invention, the sag portion is formed within a range of 20 degrees with the lens optical center as a base point when viewed from the direction of the lens optical axis.

According to another aspect of the present invention, there is provided a lighting fixture comprising the lighting lens described above.

According to the present invention, good uniformity can be obtained while suppressing glare.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the whole structure of the tunnel lighting fixture which concerns on embodiment of this invention. It is a figure which shows the installation state of a tunnel lighting fixture. It is a perspective view of a light source unit. It is a top view which expands and shows the lens part with which a light source unit is provided. FIG. 5 is a cross-sectional view showing a cross section taken along line VV of FIG. 4; FIG. 5 is a cross-sectional view showing a cross section taken along the line VI-VI of FIG. 4; FIG. 5 is a cross-sectional view of the lens portion viewed from the VII-VII line cross section of FIG. 4; FIG. 3 shows a tunnel luminaire, a comparative example and sinusoidal isoluminous curves of the comparative example. FIG. 5 is a conceptual diagram showing a comparison between the tunnel lighting fixture according to the present embodiment and a conventional product with respect to the relationship between vertical angle and luminous intensity. FIG. 5 is a perspective view of a light source unit with a different lens plate shown in FIG. 4; 11 is an enlarged plan view showing the lens portion in FIG. 10; FIG. FIG. 12 is a cross-sectional view showing a cross section taken along the line XII-XII of FIG. 11; FIG. 12 is a cross-sectional view showing a cross section taken along line XIII-XIII of FIG. 11; It is the perspective view which looked at the side of the back surface of the lens plate. It is a figure which expands and shows the lens part of FIG. FIG. 4 is an explanatory diagram of a stray light generation mechanism; FIG. 11 is a diagram showing sine isoluminous curves of a tunnel lighting fixture in which light distribution is controlled using the lens plate shown in FIG. 10;

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing the overall configuration of a tunnel lighting fixture 1 according to this embodiment. FIG. 2 is a sectional view showing an installation state of the tunnel lighting fixture 1. As shown in FIG.
As shown in FIG. 1, the front surface of the tunnel lighting fixture 1 is configured as an emission surface 1A, and as shown in FIG. It is installed and illuminates the road surface by emitting illumination light from the emission surface 1A.

As shown in FIG. 1, the tunnel lighting fixture 1 of the present embodiment includes a substantially rectangular parallelepiped housing 2 having a longitudinal direction in the traffic direction D of a tunnel A (road), and an exit surface 1A side of the housing 2. A cover 3 made of a substantially rectangular plate-shaped translucent material that closes an emission opening (not shown) formed in the housing, an opening and closing mechanism 4 that supports the cover 3 so that it can be opened and closed, and a closed cover 3 in a housing. and a fastener 5 that engages with 2.

Further, the tunnel lighting fixture 1 is provided with mounting plates 6 at both ends of the housing 2, and as shown in FIG. installed in tunnel A at an angle ranging from 20 degrees to 50 degrees). The mounting angle α is the vertical downward direction GA with the optical axis of the tunnel lighting fixture 1 (hereinafter referred to as fixture optical axis FA) and the optical center of the tunnel lighting fixture 1 (hereafter referred to as fixture optical center OA) as a starting point. is the angle formed by .

A light source unit 10 that emits illumination light is arranged inside the housing 2, and general tunnel lighting equipment such as a device for controlling lighting of the light source unit 10 and power supply related parts The members provided by are also housed in the housing 2 . In addition, the number of the light source units 10 with which the tunnel lighting fixture 1 is provided is arbitrary.

FIG. 3 is a perspective view showing the configuration of the light source unit 10. As shown in FIG. 4 is an enlarged plan view showing one lens portion 20 included in the light source unit 10, FIG. 5 is a cross-sectional view showing a cross section taken along line VV in FIG. 4, and FIG. 6 is a cross section along line VI-VI in FIG. It is sectional drawing which shows a cross section.
The light source unit 10 includes a light source substrate 12 and a lens plate 14 provided over the light source substrate 12, as shown in FIG.
As shown in FIGS. 5 and 6, the light source board 12 includes a plurality of SMD (Surface Mount Device) type LEDs 30, which are an example of light emitting elements, and a circuit board 32 on which the LEDs 30 are mounted.

As shown in FIG. 3, the lens plate 14 is a member formed by, for example, resin molding of an optically transparent resin material. It is a member provided with a portion 20 . Each lens unit 20 is provided at a position individually covering the LEDs 30 as shown in FIGS. These lens units 20 have the same configuration, and each form a laterally elongated symmetrical light distribution extending symmetrically in both directions of the traffic direction D of the tunnel A (road) centering on the housing 2 .
Specifically, as shown in FIG. 4, the lens portion 20 is a convex lens having a shape similar to a cocoon extending in the traffic direction D in a plan view. , and the LED 30 is arranged at the optical center (hereinafter referred to as the lens optical center OB) set on the first axis C1, so that the LED 30 is symmetrical in both directions of the traffic direction D The emitted light of the LED 30 is emitted.

In addition, when the tunnel lighting fixtures 1 are installed at intervals of at least 20 meters or more, the lens unit 20 of the present embodiment suppresses glare, and furthermore, the overall uniformity of road surface luminance is 0.4 or more. Light distribution is controlled as follows.

As shown in FIGS. 4, 5, and 6, the lens portion 20 includes a convex output surface 22 that is oval in plan view, and an incident surface 24 that is recessed toward the output surface 22 side. there is At least the light emitting portion of the LED 30 is accommodated within the incident surface 24 , and most of the emitted light from the LED 30 is incident on the incident surface 24 .

As shown in FIG. 5, in a cross section perpendicular to the traffic direction D, the incident surface 24 is inclined with respect to the optical axis of the LED 30 (hereinafter referred to as the light source optical axis FB) so that the vertically downward direction GA side is higher. The emitted light of the LED 30 incident on the incident surface 24 is refracted to the opposite side of the vertically downward direction GA, and more light is directed to the road surface or wall surface A1 on the far side from the tunnel lighting fixture 1. As a result, the road surface and wall surface A1 on the far side from the tunnel lighting fixture 1 are distributed with sufficient luminous intensity to obtain a certain level or more of the average luminance and uniformity of the road surface, and the wall surface luminance, and the visibility of the road surface and wall surface A1 on the far side is improved. sufficiently secured.

As shown in FIG. 6, in the cross section in the traffic direction D, the exit surface 22 has curved shoulders 22A at both ends that refract the light to the far side in the traffic direction D to exit the light. , the light is emitted from the shoulder portion 22A toward the distance in both directions of the traffic direction D, forming a horizontally elongated light distribution that allows the installation interval of the tunnel lighting fixtures 1 to be widened. The curved surface shape such as the curvature of the shoulder portion 22A is appropriately designed according to the installation interval of the tunnel lighting fixtures 1. As shown in FIG.

Further, as shown in FIG. 6, a central portion 22B, which is substantially the center of the exit surface 122 in the traffic direction D and intersects the light source optical axis FB (lens optical center OB), is recessed toward the entrance surface 24 side. A recess 60 is provided. As a result, light in the vicinity of the light source optical axis FB of the LED 30 is refracted by the concave portion 60 toward the far side in the traffic direction D and emitted, so that a sufficient amount of light can be secured at the far side.

7 is a cross-sectional view of the lens portion 20 viewed from the VII-VII line cross section of FIG. 4, showing the configuration of the sag portion 50. As shown in FIG.
As shown in FIGS. 4 and 7, on the exit surface 22 of the lens portion 20, the shoulder portions 22A at both ends are formed with sag portions 50 that act on the light emitted from the shoulder portions 22A. As shown in FIG. 4, the sag portion 50 is configured such that the shoulder portion 22A extends along a second axis line (second axis line perpendicular to the first axis C1) C2 passing through the lens optical center OB and parallel to the traffic direction D. It is a recess extending to the end 20T of the portion 20. FIG.

A cross-sectional shape of the sag portion 50 parallel to the first axis C1 is, for example, a U-shape close to a parabolic curve.
On the other hand, the surface of the sag portion 50 includes an uneven shape in the direction of the second axis C2. Specifically, as shown in FIGS. 4 and 7, the sag portion 50 includes a first convex portion 52, a first convex portion 52, a first convex portion 52, a first convex portion 52, a first convex portion 52, a first convex portion 52, a first convex portion 52, and It includes a first sag 53 , an inter-sag protrusion 54 , a second sag 55 and a second protrusion 56 . The first convex portion 52, the inter-sag convex portion 54, and the second convex portion 56 are all curved curved portions, and the first sag portion 53 and the second sag portion 55 are curved concave portions. . A two-step sag shape is formed in the recessed portion of the sag portion 50 by the continuation of the first sag portion 53 , the inter-sag convex portion 54 and the second sag portion 55 .
Further, as shown in FIG. 7, the sag portion 50 is such that the curvature (bottom surface curvature) of the bottom surface 53A of the first sag portion 53 closer to the lens optical center OB is the second sag portion farther from the lens optical center OB. It is larger than the curvature of the bottom surface 55A of 55 (bottom surface curvature).
On the other hand, for the outer shape portion 50A corresponding to the edge of the recessed portion of the sag portion 50, as shown in FIG. (That is, the outer shape portion 50 is changed into a curved shape that does not include unevenness).

By forming the sag portion 50 in the shoulder portion 22A, the glare at a distance in the traffic direction D is suppressed, and an overall uniformity of 0.4 or more is obtained.
The sag portion 50 includes the light source optical axis FB and has an inclination angle γ (FIG. 7) of 40 degrees from the light source optical axis FB with respect to the light emission center 30A of the LED 30 in a cross section along the traffic direction D of the road. to 75 degrees, and in this embodiment, the sag portion 50 is provided over a range of γ from about 42 degrees to about 73 degrees.
In addition to the sag portion 50, a plurality of recesses 25 are formed on the exit surface 22, as shown in FIG. Even without these concave portions 25, the effect of suppressing glare and the overall degree of uniformity of 0.4 or more are obtained.

FIG. 8 is a diagram showing sine isoluminous curves of the tunnel lighting fixture 1 installed at a predetermined mounting angle α. The directions in which the horizontal angles φ of the sinusoidal isoluminous curves are 0° and 180° correspond to the direction G shown in FIG. direction.
As shown in the figure, the light distribution control of the lens portion 20 reduces the luminous intensity in the range RA where the horizontal angle φ is 90 degrees and the vertical angle θ is 60 degrees or more. This range RA includes 75 degrees or more, which is the range of the vertical angle θ that affects glare. Visible glare will be reduced. In addition, in the tunnel lighting fixture 1 of the present embodiment, the relative threshold increase (TI) is 15% or less, and visual performance deterioration glare is sufficiently suppressed.

In addition, by controlling the light distribution of the lens unit 20, the vertical angle θ is in the range of 70 degrees or less, and both sides of the horizontal angle φ = 90 degrees (more precisely, the horizontal angles φ = 80 degrees and 110 degrees). A luminance peak occurs in the range RB, which improves the road surface luminance uniformity, and an overall uniformity of 0.4 or more is obtained.

Here, the range of the vertical angle θ at which light is attenuated by the sag portion 50 varies depending on the groove width WA (FIG. 4) of the sag portion 50 in the direction of the second axis C2. The angle range of the vertical angle θ is expanded to the low angle side. As shown in FIG. 4, when the output surface 22 of the lens portion 20 is viewed from the direction of the lens optical axis FC and the range of the angle β is defined with the lens optical center OB as the base point, the angle β is 20 degrees. If the groove width WA is wider than the range below, the angle range RθB (FIG. 9) of the vertical angle θ in which glare is less likely to be felt is also attenuated, adversely affecting the lighting of the road surface.
Therefore, the sag portion 50 is preferably formed within a range in which the angle β is 20 degrees or less.
On the other hand, the narrower the groove width WA, the narrower the range in which the glare reduction effect is exhibited, but the more difficult it becomes to form the lens portion 20, which increases the manufacturing difficulty.
Therefore, the sag portion 50 of the present embodiment is formed with a groove width WA corresponding to a range in which the angle β is 17 degrees, so that production can be performed with the same method and quality as usual.

FIG. 9 is a conceptual diagram showing a comparison of the relationship between the vertical angle and the luminous intensity between the tunnel lighting fixture 1 of this embodiment and a conventional product. The conventional product has a conventional optical control system in place of the lens portion 20 (lens plate 14), and is a wide-span tunnel lighting fixture that can be installed at the same installation intervals as the present embodiment.
As shown in the figure, in the tunnel lighting fixture 1 of the present embodiment, the sag portion 50 is provided on the shoulder portion 22A of the lens portion 20, so that the luminous intensity is reduced in the angle range RθA of the vertical angle θ where glare is a problem. While the glare is suppressed to the same level as the product, the luminous intensity in the angle range RθB where it is difficult to feel the glare increases, and the uniformity of the road surface luminance can be improved.

Thus, in the lens portion 20 of this embodiment, the sag portions 50 including the inter-sag convex portions 54 are formed on both shoulder portions 22A in the traffic direction D. As shown in FIG.
As a result, the luminous intensity in the angular range RθA where glare is a problem is suppressed, while the luminous intensity in the angular range RθB where glare is less likely to be perceived increases, so that the uniformity of road surface brightness can be improved while suppressing glare.

In addition, in the lens portion 20 of the present embodiment, the sag portion 50 is formed within an angle range of 20 degrees with the lens optical center OB as a base point, so that it is possible to prevent dimming in the angle range RθB in which glare is less likely to be felt.

By the way, according to the lens plate in which lens portions are formed on the surface of the light-transmitting base plate like the lens plate 14 of the present embodiment, most of the light emitted from the LEDs 30 is transmitted and used for illumination. By designing it, the uniformity of the road surface brightness and the illumination rate can be efficiently improved.

On the other hand, since the LED 30 is not a perfect point light source and has a finite size of the light emitting portion, stray light different from the emitted light as optically designed may be generated in the lens plate.
The inventors have found that stray light that causes luminance unevenness that may adversely affect the driver can also occur on the wall surface A1 of the tunnel A and the road surface, and as a result of intensive studies, one of the causes of such stray light is The present inventors have found that this is in the base plate of the lens plate and have invented a lens plate capable of suppressing stray light caused by this base plate.
Such a lens plate will be described below.

FIG. 10 is a perspective view showing the light source unit 110 with the lens plate 114. As shown in FIG.
The light source unit 110 has the same configuration as the light source unit 10 shown in FIG. 4 except that the configuration of the lens plate 114 is different.
The lens plate 114 is a member formed by resin molding of an optically transparent resin material, and is a member in which a plurality of lens portions 120, which are light control portions, are provided on a surface 140A of a base plate 140 having a flat plate shape. be. Each lens unit 120 is provided at a position that individually covers the LEDs 30, similarly to the lens unit 20 of the lens plate 14 shown in FIG. A horizontally long symmetrical light distribution extending symmetrically in both directions of the traffic direction D of the tunnel A (road) with 2 as the center is formed.

FIG. 11 is a plan view showing an enlarged lens portion 120 in FIG. FIG. 12 is a cross-sectional view showing the XII-XII line cross section of FIG. FIG. 13 is a cross-sectional view showing a cross section taken along line XIII--XIII of FIG.
As shown in FIGS. 11, 12, and 13, the lens unit 120 includes an output surface 122 that is oval in plan view and convex in cross section, and an incident surface 124 that is recessed toward the output surface 122 side. ing. By aligning the light source optical axis FB with the lens optical center OB and accommodating at least the light emitting portion of the LED 30 in the incident surface 124, most of the emitted light from the LED 30 is incident on the incident surface 124. . Furthermore, as shown in FIG. 13, in the cross section in the traffic direction D, the exit surface 122 has curved shoulders 122A at both ends that refract the light to the far side in the traffic direction D and exit it. there is As a result, the light is emitted farther in both directions of the traffic direction D from the shoulder portion 122A, and a horizontally elongated light distribution is formed in which the installation interval of the tunnel lighting fixtures 1 can be widened.

In addition, a recess 160 recessed toward the entrance surface 124 is provided in a central portion 122B that is substantially at the center of the exit surface 122 in the traffic direction D and intersects with the light source optical axis FB (lens optical center OB). As a result, light in the vicinity of the light source optical axis FB of the LED 30 is refracted by the concave portion 160 toward the far side in the traffic direction D, and a sufficient amount of light is ensured at the far side.

Unlike the lens portion 20 shown in FIG. 4, the lens portion 120 does not have the sag portion 50 having a glare suppressing effect, but like the lens portion 20, an overall uniformity of 0.4 or more can be obtained. Light distribution is controlled as follows. In addition, the lens unit 120 controls the light distribution so that the lane axis uniformity is 0.6 or more when the tunnel lighting fixtures 1 are installed at an installation interval of about 17 meters.

14 is a perspective view of the rear surface of the lens plate 114, and FIG. 15 is an enlarged view of the lens portion 120 of FIG.
As shown in these figures, in the lens plate 114 , diffusion portions 170 for suppressing stray light are provided around each lens portion 120 on the rear surface 140 B of the base plate 140 .

To be more specific, the inventors have found through extensive studies that stray light is not emitted from the emission surface 122 of the lens unit 120, and light reflected toward the LED 30 is totally reflected by the back surface 140B of the base plate 140. was found to be the cause.
Specifically, as shown in FIG. 16, the light from the LED 30 is reflected inside the light emitting surface 122 of the lens portion 120 toward the inside of the lens portion 120 (light S1 in the figure), and the reflected light S1 is Totally reflected toward the lens portion 120 by the rear surface 140B of the base plate 140 (light S2 in the figure), the reflected light S2 is emitted from the exit surface 122 of the lens portion 120 in an irregular direction (light S2 in the figure). , light S3), and this light S3 becomes stray light.

Therefore, as shown in FIG. 15, on the rear surface 140B, the diffusing portion 170 is provided in an area TA (an area corresponding to the lens portion 120) where the light S1 returning to the rear surface of the base plate 140 is incident. When the lens portion 120 forms a symmetrical light distribution, the area TA is adjacent to the edge portion 124A of the incident surface 124 on both sides in the traffic direction D across the lens portion 120, and each area TA is the first axis line. It is symmetrical about C1.

The diffusing portion 170 is formed by forming a large number of dimples 172 in the area TA of the back surface 140B, and by providing planar portions 174 in the gaps between the dimples 172. Each dimple 172, And the plane part 174 changes the reflection direction of the light S1 returned there, or transmits the light S1 to the light source substrate 12 side, thereby diffusing the light S1, thereby suppressing stray light.

Although the dimple 172 may have any suitable shape, the shape of the dimple 172 is preferably hemispherical or conical. Also, the ratio of the maximum diameter to the depth of the dimple 172 is preferably about 1:1. Further, in the diffusion portion 170, it is preferable that the individual dimples 172 are small in size and large in number, but the maximum diameter is preferably 1 mm or more so as not to increase the difficulty of manufacturing.

FIG. 17 is a diagram showing sine isoluminous curves of the tunnel lighting fixture 1 in which the light distribution is controlled using the lens plate 114. FIG. The same figure shows the sine isoluminous curves when the lens plate 114 is provided with the diffuser 170 and when it is not provided with the diffuser 170 .
As shown in the figure, when the lens plate 114 does not have the diffuser 170, the luminous intensity unevenness due to the stray light occurs in the range RC. The sinusoidal isoluminous curve indicates the luminous intensity distribution of the tunnel lighting fixture 1. When the reflectance of the wall surface A1 and the road surface is substantially constant over the entire surface, if there is luminous intensity unevenness in the range RC, the luminous intensity unevenness causes the range Brightness unevenness occurs on the wall surface A1 and the road surface at the location corresponding to the RC. In particular, when the road surface is paved with asphalt, the specular reflectance is higher than that of the concrete road surface, resulting in stronger luminance unevenness.
On the other hand, when the lens plate 114 has the diffusing portion 170, it can be seen that the luminous intensity unevenness in the range RC is eliminated. It can be seen that unevenness is prevented.

As described above, according to the lens plate 114, the diffusion portion 170 for diffusing light is provided in the area TA corresponding to the lens portion 120 on the back surface 140B of the base plate 140. Stray light due to total reflection of S1 can be suppressed, and luminance unevenness on the wall surface A1 of the tunnel A and the road surface can be suppressed.

Note that the above-described embodiment is merely an example of one aspect of the present invention, and can be arbitrarily modified and applied without departing from the gist of the present invention.

The present invention is applicable not only to tunnel lighting fixtures installed in the tunnel A, but also to any lighting fixtures that illuminate the road surface.
Unless otherwise specified, the horizontal and vertical directions, various numerical values, and shapes in the above-described embodiments include ranges (so-called equivalent ranges) that produce the same effects as those directions, numerical values, and shapes.

1 Tunnel lighting equipment (lighting equipment)
Reference Signs List 10, 110 light source unit 12 light source substrate 14, 114 lens plate 20, 120 lens portion (lighting lens)
22, 122 exit surface 22A, 122A shoulder portion 24, 124 entrance surface 30 LED (light emitting element)
40, 140 base plate 50 sag portion 54 convex portion between sag (convex portion)
140B Back surface 170 Diffusion part 172 Dimple 174 Flat part D Traffic direction FB Light source optical axis FC Lens optical axis OB Lens optical center

Claims (6)

A lighting lens that is provided in a lighting fixture that illuminates a road surface, controls light emitted from a light-emitting element included in the lighting fixture, and forms a horizontally symmetrical light distribution extending in both directions of the traffic direction of the road,
a convex exit surface;
an incident surface that covers the light emitting element and is recessed toward the output surface;
with
The exit surface is
Both shoulders in the traffic direction are formed with sag portions including protrusions therein.
An illumination lens characterized by: The sag portion has a first sag portion and a second sag portion respectively closer to and farther from the lens optical center than the convex portion, and the bottom surface curvature of the first sag portion is equal to the bottom surface curvature of the second sag portion. 2. An illumination lens according to claim 1, characterized in that it is greater than. 3. The lighting lens according to claim 1, wherein in a cross section along the traffic direction of the road, an angle change of the outer shape of the sag portion with respect to the light source optical axis changes continuously. The sag portion is
In a cross section along the traffic direction of the road including the light source optical axis,
The illumination lens according to any one of claims 1 to 3, wherein the angle of inclination from the optical axis of the light source is set within a range of 40 degrees to 75 degrees with the center of the light emitting element as a base point. The sag portion is
5. The illumination lens according to any one of claims 1 to 4, wherein the illumination lens is formed within a range of 20 degrees from the optical center of the lens when viewed from the direction of the lens optical axis. A lighting fixture comprising the lighting lens according to claim 1 .

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