JP6345632B2 - Illumination device, optical member, and optical member design method - Google Patents

Description

The present invention is used as a hollow edge light illumination or an external illumination signboard illumination used for an interior lighting signboard, etc., and is a lighting device , an optical member, and an optical member design method for suppressing color unevenness and illumination intensity unevenness on a light irradiation surface About.

  In recent years, there is an illuminating device using an LED as a light source, which suppresses color unevenness on a light irradiation surface (see Patent Document 1).

  This illuminating device includes a white LED as a light source and a lens having a recess for housing the LED. The lens has a first incident surface, a second incident surface, and a third incident surface on which light emitted from the white LED is incident on the concave portion, and is further incident from the first incident surface, the second incident surface, and the third incident surface. A reflecting surface for reflecting the reflected light in the light irradiation direction, and an exit surface for emitting the light reflected by the reflecting surface in the light irradiation direction. The first incident surface and the second incident surface are surfaces on which light in the central region of the light emitting range of the white LED is incident, and the third incident surface is a surface on which light in a region outside the central region is incident. The light incident on the third incident surface contains a lot of yellow light and causes yellow ring. However, the light incident on the third incident surface is reflected so as not to be concentrated on a specific area. By designing the surface, uneven color of the light irradiated on the light irradiation surface is suppressed.

JP 2014-38233 A

  However, the conventional illumination device suppresses uneven color of the light irradiated on the light irradiation surface, but the optical axis of the white LED as the light source and the normal direction of the light irradiation surface are matched. In applications where the optical axis of the light source and the normal direction of the light irradiation surface are orthogonal, for example, when used as a hollow edge light, the illuminance of light irradiated near the light source on the light irradiation surface is There exists a problem that it becomes low and does not necessarily suppress uneven illumination.

Accordingly, an object of the present invention is to be used as hollow edge light illumination or external illumination signboard illumination used for an interior lighting signboard, and suppresses unevenness in color and illuminance of light irradiated on a light irradiation surface. Another object of the present invention is to provide a lighting device , an optical member, and a method for designing the optical member .

[1] a semiconductor light emitting device;
A first shaping unit that distributes light from a first emission surface at a wide angle in the optical axis direction of the semiconductor light emitting device with a light beam emitted from the semiconductor light emitting device and incident on a first incident surface formed on the bottom surface of the recess as a central light beam When the emitted from the semiconductor light emitting device, the optical axis direction from the second emission surface as a peripheral light flux to the light beam incident on the second incident face to form a side by total reflection to condensed by the reflecting surface of the concave portion An optical member having a second shaping unit that emits light having a narrower light distribution angle than the central light flux ,
The first emission surface of the first shaping unit and the second emission surface of the second shaping unit are planes having normal lines parallel to the optical axis,
The second shaping unit has a trough of illuminance at a first distance when irradiating light emitted from the second emission surface on an irradiation surface parallel or substantially parallel to the optical axis direction,
The first incident surface of the first shaping unit complements the valley of the illuminance of the second shaping unit to the first distance when the irradiation surface is irradiated with light emitted from the first emission surface. An illumination device designed to have a concave aspherical shape so as to have a peak of illuminance.
[2] The illumination device according to [1], wherein the second shaping unit emits light parallel or substantially parallel to the optical axis from the second emission surface .
[3] In the semiconductor light emitting device according to [1] or [2], the phosphor that is excited by the first color light emitted from the semiconductor light emitting device and emits the second color light is provided on the surface . The lighting device described.
[ 4 ] A first light that is emitted from the semiconductor light emitting element and is distributed at a wide angle in the optical axis direction of the semiconductor light emitting element from the first emission surface as a central light beam that is incident on the first incident surface formed on the bottom surface of the recess. Shaping section;
Said emitted from the semiconductor light emitting element, the center from the second emission surface as a peripheral light flux to the light beam incident on the second incident face to form a side by total reflection to condensed by the reflecting surface of the concave portion in the optical axis direction A second shaping unit that emits light having a narrower light distribution angle than the luminous flux ,
The first emission surface of the first shaping unit and the second emission surface of the second shaping unit are planes having normal lines parallel to the optical axis,
The second shaping unit has a trough of illuminance at a first distance when irradiating light emitted from the second emission surface on an irradiation surface parallel or substantially parallel to the optical axis direction,
The first incident surface of the first shaping unit complements the valley of the illuminance of the second shaping unit to the first distance when the irradiation surface is irradiated with light emitted from the first emission surface. An optical member designed in a concave aspherical shape so as to have a peak of illuminance .
[5] A first shaping unit that distributes light at a wide angle in the optical axis direction of the semiconductor light emitting element as a central light beam emitted from the semiconductor light emitting element;
Design of an optical member having a second shaping unit that condenses a peripheral light beam emitted from the semiconductor light emitting element to the periphery of the central light beam and emits light having a narrower light distribution angle than the central light beam in the optical axis direction A method,
When the light emitted from the second shaping unit is irradiated on an irradiation surface parallel or substantially parallel to the optical axis direction, obtaining a first distance of the valley of illuminance;
When the irradiation surface is irradiated with light emitted from the first shaping unit, the first shaping unit has an illuminance peak that complements the illuminance valley of the second shaping unit at the first distance. And designing the optical member.

  ADVANTAGE OF THE INVENTION According to this invention, in the use as a hollow edge light illumination used for an internal lighting signboard, an external lighting signboard illumination, etc., the color nonuniformity and illumination nonuniformity of the light irradiated with respect to a light irradiation surface can be suppressed.

FIG. 1 is a schematic perspective view showing an example of the configuration of an internal lighting signboard using the illumination device according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of the interior lighting signboard. FIG. 3 is a longitudinal sectional view showing a schematic configuration example of the illumination device according to the first embodiment of the present invention. FIG. 4 is a schematic view showing an optical path of light emitted from the LED light source. FIG. 5 is a graph showing the relationship between the distance from the LED illumination device on the light irradiation surface and the illuminance of light irradiated at the distance. FIGS. 6A to 6C show light irradiated on the light irradiation surface by the LED illumination device. FIG. 7 is a graph showing the relationship between the distance from the LED illumination device on the light irradiation surface and the chromaticity (x coordinate by CIE) of light irradiated at the distance. FIG. 8 is a graph showing the relationship between the distance from the LED illumination device on the light irradiation surface and the chromaticity (y coordinate by CIE) of light irradiated at the distance. FIG. 9 is a longitudinal sectional view showing a schematic configuration example of a lighting device as a comparative example of the first embodiment. FIG. 10 is a longitudinal sectional view showing a schematic configuration example of a lighting device as a comparative example of the first embodiment. FIG. 11 is a graph showing the relationship between the distance from the LED illumination device on the light irradiation surface and the illuminance of light irradiated at the distance. FIG. 12 is a longitudinal cross-sectional view illustrating a schematic configuration example of the illumination device serving as a first modification of the first embodiment. FIG. 13 is a schematic diagram showing an optical path of light emitted from the LED light source of the illumination device shown in FIG. FIG. 14 is a longitudinal cross-sectional view illustrating a schematic configuration example of a lighting device serving as a second modification of the first embodiment. FIG. 15 is a schematic diagram showing an optical path of light emitted from the LED light source of the illumination device shown in FIG. FIG. 16: is a longitudinal cross-sectional view which shows the example of a schematic structure of the illuminating device which concerns on the 2nd Embodiment of this invention. FIG. 17 is a schematic diagram illustrating an optical path of light emitted from the LED light source of the illumination device illustrated in FIG. 16. FIG. 18 is a longitudinal cross-sectional view illustrating a schematic configuration example of a lighting device as a first modification of the second embodiment. FIG. 19 is a schematic diagram showing an optical path of light emitted from the LED light source of the illumination device shown in FIG. FIG. 20 is a longitudinal cross-sectional view illustrating a schematic configuration example of a lighting device serving as a second modification of the second embodiment. FIG. 21 is a schematic diagram illustrating an optical path of light emitted from the LED light source of the illumination device illustrated in FIG. 20. FIG. 22 is a schematic perspective view showing another example of the configuration of the internal lighting signboard using the illumination device. FIG. 23 is a graph showing the relationship between angle and luminous intensity. FIG. 24 is a graph showing the relationship between the angle and the vertical surface illuminance.

  Hereinafter, embodiments and examples of the present invention will be described with reference to the drawings. In addition, in each figure, about the component which has the substantially same function, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted.

[First Embodiment]
FIG. 1 is a schematic perspective view showing an example of the configuration of an internal lighting signboard using the illumination device according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the configuration of the interior lighting signboard.

  The inner signboard 2 has panel portions 3 and 4 that diffuse light to the outside by being irradiated with light from the inside, an outer frame portion 5 that holds the panel portions 3 and 4, and a lower side inside the outer frame portion 5. A plurality of LED illuminating devices 100 </ b> A that are arranged and irradiate the panel portions 3 and 4 with light.

  The LED illumination device 100A has an optical axis 110a of an LED element 1 (FIG. 3), which will be described later, in the vertical direction in FIG. 2, and is orthogonal to the normal lines of the light irradiation surfaces 30 and 40 of the panel portions 3 and 4, respectively. . The optical axis 110a and the normal lines of the light irradiation surfaces 30 and 40 may be provided with an angle of 90 ° to several degrees without being completely orthogonal. In other words, the optical axis 110a and the light irradiation surfaces 30 and 40 are parallel or substantially parallel.

Vertical illuminance E _v of the light irradiated to the position L1 and L2 in the light irradiation surface 30 and 40, the sinθ times the illuminance E of the light emitted at an angle θ with respect to the optical axis 110a.

(Configuration of lighting device)
FIG. 3 is a longitudinal sectional view showing a schematic configuration example of the illumination device according to the first embodiment of the present invention. FIG. 4 is a schematic diagram showing an optical path of light emitted from the LED light source 110.

The illumination device 100A includes an LED light source 110, which is a light source with a wide-angle light distribution using LED elements whose energization direction is a vertical direction, and light in the vicinity of the optical axis 110a of light emitted from the LED light source 110 with a wide-angle light distribution angle. The light l _ci is collected to emit light at a wide light distribution angle, and the light l _oi around the optical axis 110a out of the light emitted from the LED light source 110 is condensed to form a narrow light distribution angle. And an optical member 130A that emits light. The LED element is an example of a semiconductor light emitting element. The optical member 130A is an example of an optical system.

(Configuration of LED light source)
The LED light source 110 includes the LED element 1 and, as an example, a heat dissipation structure including a copper block 111 and a radiator 117. The heat dissipation structure may be a resin substrate or an aluminum substrate. The LED light source 110 further includes a phosphor that emits light of the second color when excited by the first color of light emitted from the LED element. The phosphor may be a powdery substance attached to the surface of the LED element 1 via a resin, or a phosphor containing a phosphor may be formed on the surface of the LED element 1. For example, an LED element that emits light of a blue color is used as the LED element 1, and a YAG phosphor that converts blue light into yellow light, a BOS phosphor, or the like as a phosphor. By using the LED light source 110, the blue light emitted from the LED element and the yellow light emitted from the phosphor are mixed and emitted to emit white light.

  For example, the LED element 1 is formed so as to partially disperse and cover an n-type semiconductor substrate and the surface of the n-type semiconductor substrate, and a difference in refractive index from the n-type semiconductor substrate is 0.15 or less. A dielectric layer, an n-type semiconductor layer formed on the n-type semiconductor substrate via the dielectric layer, and in contact with the dielectric layer and a portion of the surface of the n-type semiconductor substrate that is not covered with the dielectric layer; a light-emitting layer formed on the n-type semiconductor layer, a p-type semiconductor layer formed on the light-emitting layer, an n-type electrode formed on the opposite side of the surface on which the dielectric layer of the n-type semiconductor substrate is formed, And a p-type electrode formed on the p-type semiconductor layer.

(Configuration of optical member)
The optical member 130A includes an incident surface 131a _A formed in a concave aspherical shape on which light l _ci near the optical axis 110a is incident out of light emitted from the LED light source 110 with a wide light distribution angle, and an incident surface 131a. _A light emitting surface 131b that emits light l _ci having a wide light distribution angle by being refracted at _A , and a substantially cylindrical shape from which light l _oi around the optical axis 110a is incident out of the light emitted from the LED light source 110. An incident surface 132b, a reflecting surface 132c that totally reflects the light l _oi refracted by the incident surface 132b, and an emitting surface 132d that emits the light l _oi having a narrow light distribution angle by being reflected by the reflecting surface 132c. Is provided.

The path of the light l _ci in the entrance surface 131a _A , the exit surface 131b, and the optical member 130A is referred to as a first shaping lens unit. The path of the light l _{oi in} the incident surface 132b, the reflecting surface 132c, the emitting surface 132d, and the optical member 130A is referred to as a second shaping lens unit. In the first embodiment, the first and second shaping lens portions have overlapping regions in the optical member 130A.

  The first and second shaping lens portions are made of a transparent resin such as an acrylic resin, for example. Here, the first shaping lens unit is an example of a first shaping unit, and the second shaping lens unit is an example of a second shaping unit. In FIG. 3, P indicates the position of the point light source. The optical member 130A has a rotationally symmetric shape about the optical axis 110a.

Here, a light beam transmitted through the first shaping lens unit is referred to as a central light beam l _c . Further, a light beam that is irradiated through the second shaping lens unit is referred to as a peripheral light beam l _o .

  The reflecting surface 132c of the second shaping lens unit is designed so that the light refracted by the incident surface 132b can be incident at an angle larger than the critical angle, and the reflected light becomes as narrow-angle light as possible on the optical axis 110a. It is a surface approximated to a surface obtained by rotating an aspherical shape such as a rotating paraboloid or a Bezier curve obtained by rotating a parabola around the optical axis 110a. A reflecting mirror such as a metal plate may be used instead of the reflecting surface 132c of the second shaping lens unit.

  The exit surface 131b of the first shaping lens unit and the exit surface 132d of the second shaping lens unit are planes orthogonal to the optical axis and have a circular shape.

  FIG. 5 is a graph showing the relationship between the distance from the LED illumination device 100A on the light irradiation surface 30 or 120 and the illuminance of light irradiated at the distance. FIGS. 6A to 6C show light irradiated on the light irradiation surface 30 or 120 by the LED illumination device 100A. The distance from the LED lighting device 100A and the angle θ from the optical axis 110a of the LED lighting device 100A described below are examples, and vary depending on the design of the LED lighting device 100A and the positional relationship with the light irradiation surfaces 30 and 40. The value to be

As shown in solid line and 6 (b) of FIG. 5, the central ray l _c, the peak of the illuminance at a distance relatively close from the LED lighting device 100A (around 40 mm) because it is light distribution in a wide angle Have.

As shown in the thin broken line in FIG. 5 and FIG. 6C, the peripheral luminous flux l _o is distributed at a narrow angle, so that the illuminance of the illuminance is at a relatively far position (around 120 mm) from the LED illumination device 100A. It has a peak and has a valley of illuminance at a relatively short distance (around 40 mm). It should be noted that the distance of the valley of the illuminance of the peripheral light beam l _o coincides with the peak distance of the central light beam l _c .

Therefore, as shown in the thick broken line in FIG. 5 and FIG. 6A, the total luminous flux is a combination of the central luminous flux l _c and the peripheral luminous flux l _o , so that the illuminance valley of the peripheral luminous flux l _o is the central luminous flux. Illuminance that is compensated by the illuminance peak of l _c and gradually and monotonously decreases after the distance of 120 mm is obtained.

Here, the reason why the peripheral light l _o the illuminance of the valley occurs will be described with reference to FIG. 2, FIGS. 23 and 24. FIG. 23 is a graph showing the relationship between the angle θ and the luminous intensity I. Further, FIG. 24 is a graph showing a relationship between the angle θ and the vertical plane illuminance E _v.

First, in general, the vertical illuminance of the light irradiation surface is E _v = Esin θ. Therefore, when θ is brought close to 0, the E _v component decreases. Further, since the distance between the LED lighting device 100A and the light irradiation surface 30 and 40 which increases in 1 / sin [theta times relative to the time of θ = 90 °, _{E v} by the inverse square law of the distance brought close to theta to 0 sin ² decreases to θ times. That is, when referred to the case of θ = 90 °, _{E v} is the sin ³ theta times. In order to compensate for this decrease and aim for uniform illumination, it is necessary to increase the luminous intensity in a region where θ is small, so that the required light distribution has a narrow angle.

If the light distribution of the narrow-angle light distribution lens is a Gaussian distribution, the relationship between the angle θ and the luminous intensity I is as shown in the graph in FIG. Normalizing in terms (× sin ³ θ) in this relationship vertical illuminance E _v, is as in the graph shown in FIG. 24.

  Suppose that θe (the angle formed by the line segment connecting the upper end surface of the light irradiation surface 30 or 40 in FIG. 2 and the LED illumination device 100A and the optical axis of the LED illumination device 100A) is 10 °. When a narrow-angle light distribution illumination device (1/2 beam angle 10 °) is selected as the LED illumination device 100A, no light intensity peak appears on the light irradiation surface 30 or 40, but light of θ <10 ° is emitted from the signboard edge. The light is not absorbed efficiently, and the illumination efficiency is low and the average illumination intensity of the light irradiation surface is low. Therefore, it is not realistic from the viewpoint of energy saving to select a lighting device with a narrow-angle light distribution. Therefore, in order to increase the average illuminance of the light irradiation surface 30 or 40, a lighting device with a wide-angle light distribution is selected.

  For example, when an illumination device having a 1/2 beam angle of 20 ° is selected as the illumination device with a wide-angle light distribution, the light irradiation surface 30 or 40 has an illuminance peak. In other words, the light use efficiency is high and the average illuminance of the light irradiation surface is high compared to a narrow-angle light distribution illuminating device, but there is a disadvantage that illuminance unevenness occurs due to the peak of illuminance.

Although not shown in the graph shown in FIG. 24, E is caused by leakage light of the LED illumination device 100A (stray light that has not been successfully captured by the optical member 130A) in the range of θ> 30 ° to 40 °. _v increases. and increase in θ> 30 ° ~40 ° in the range of E _v, to occur between the peaks of the illuminance as described above is the illumination of the valley that occurs peripheral light l _o.

  FIG. 7 is a graph showing the relationship between the distance from the LED illumination device 100A on the light irradiation surface 30 or 120 and the chromaticity (x coordinate by CIE) of light irradiated at the distance. FIG. 8 is a graph showing the relationship between the distance from the LED illumination device 100A on the light irradiation surface 30 or 120 and the chromaticity (y coordinate by CIE) of light irradiated at the distance. 7 and 8 use a LED element that emits blue light as the LED element 1, and use YAG fluorescent light that converts blue light into yellow light as a phosphor. Body, a BOS phosphor, and the like.

As shown in thin broken line in FIG. 7 and FIG. 8, the peripheral light l _o, many wavelengths affected phosphor is long light, a light close to yellow, distribution such light within a narrow angle Since it is illuminated, it has a peak at a position (near 60 mm) closer to the LED illumination device 100A than the peak position of illuminance described above. This is because many LED packages increase the light emitting area (phosphor area) of the LED package rather than the chip area of the blue LED in order to increase the light extraction efficiency.

Further, as shown in solid lines in FIGS. 7 and 8, the central ray l _c, many optical wavelength shorter not affected by the phosphor, a light close to blue. That is, color unevenness is suppressed by superimposing light close to the blue color of the central light beam lc on the portion of the peripheral light beam lo close to yellow.

(Comparative example)
FIG. 9 and FIG. 10 are longitudinal sectional views showing schematic configuration examples of a lighting device as a comparative example of the first embodiment.

The LED lighting devices 100B and 100C have optical members 130B and 130C different from the LED lighting device 100A, and the other configurations are the same. An optical member 130B and 130C are different shapes of the incident surface 131a _B and 131a _C is an incident surface 131a _A of the optical member 130A, while the incident surface 131a _A is an aspherical shape, the incident surface 131a _B by spherical The incident surface 131a _C is formed in a conical shape.

  FIG. 11 is a graph showing the relationship between the distance from the LED illumination devices 100A-100C on the light irradiation surface 30 or 120 and the illuminance of the light irradiated at the distance.

As described with reference to FIG. 5, in the optical member 130A, the distance of the valley of the illuminance of the peripheral light beam l _o coincides with the peak distance of the central light beam l _c , but in the optical members 130B and 130C, the peripheral light beam l The distance of the illuminance valley of _o does not coincide with the peak distance of the central light beam l _c .

(Effects of the first embodiment)
According to the first embodiment, the following effects can be obtained.
(1) The central light beam l _c has a wide-angle light distribution and the peripheral light beam l _o has a narrow-angle light distribution by the optical member 130A, so that color unevenness and illuminance on the light irradiation surfaces 30 and 40 when used as a hollow edge light. Unevenness can be suppressed. In addition, since the LED element 1 itself can use a light source with a wide-angle light distribution having color unevenness, it is not necessary to use an expensive light source with little color unevenness, and cost can be suppressed.
(2) Since the emission surfaces 131b and 132d of the LED lighting device 100A are configured as flat surfaces, dirt does not accumulate easily and cleaning is facilitated, and the frequency of maintenance can be suppressed.

[Modification 1]
FIG. 12 is a longitudinal cross-sectional view illustrating a schematic configuration example of the illumination device serving as a first modification of the first embodiment. FIG. 13 is a schematic view showing an optical path of light emitted from the LED light source 110 of the illumination device shown in FIG.

The illumination device 100D of Modification 1 has an optical member 130D different from the LED illumination device 100A, and the other configurations are the same. The optical member 130D is different from the shape of the incident surface 131a _D is an incident surface 131a _A of the optical member 130A, while the incident surface 131a _A is concave, incident surface 131a _D is a convex shape, the central ray l the _c is for the light collector to be incident on the exit surface 131b _D. The optical member 130D, the shape of the exit surface 131b _D is different from the emission surface 131b of the optical member 130A, whereas the emission surface 131b is a flat exit surface 131b _D is a concave shape, it is condensed the central ray l _c is for the wide angle light distribution.

With the above structure, the same central ray l _c of the first embodiment is obtained, the same effects.

[Modification 2]
FIG. 14 is a longitudinal cross-sectional view illustrating a schematic configuration example of a lighting device serving as a second modification of the first embodiment. FIG. 15 is a schematic view showing an optical path of light emitted from the LED light source 110 of the illumination device shown in FIG.

The illumination device 100E of Modification 2 has an optical member 130E different from the LED illumination device 100A, and the other configurations are the same. The optical member 130E is different from the shape of the incident surface 131a _E is the incident surface 131a _A of the optical member 130A, while the incident surface 131a _A is concave, incident surface 131a _E is a convex shape, the central ray l _c is condensed so as to be incident on the reflection surface 131b _E.

The optical member 130E is different from the optical member 130A having an exit surface 131b of the plane, focused central ray _{l c} of total reflection light irradiation surface 30 of the central ray _{l c} which is reflected and the reflection surface 131b _E to or And an emission surface 131c _E that emits in the direction of 120.

With the above structure, it is possible to light distribution of the central ray l _c a wider angle compared to the embodiment and Modification 1 of the first embodiment.

[Second Embodiment]
The second embodiment is different from the first embodiment in that it is used in an internal lighting signboard or an external lighting signboard in which the panel portion is provided only on one side rather than on both sides. The shape of the incident surface of the member is different. In addition, about the structure which is common in 1st Embodiment, the common code | symbol is attached | subjected.

(Configuration of lighting device)
FIG. 16: is a longitudinal cross-sectional view which shows the example of a schematic structure of the illuminating device which concerns on the 2nd Embodiment of this invention. FIG. 17 is a schematic view showing an optical path of light emitted from the LED light source 110 of the illumination device shown in FIG.

The illumination device 100F of the second embodiment has an optical member 130F different from the LED illumination device 100A of the first embodiment, and the other configurations are the same. The incident surface 131a _A of the optical member 130A is all a concave lens, whereas the optical member 130F is an incident surface 131a _F1 that is a half convex lens, and an incident surface 131a _F2 that is a half concave lens, which are combined. It is a thing. Incident surface 131a _F1 is a convex lens, the left side of the light beam from the optical axis 110a in out view 17 of the central ray _{l c} is condensed is intended to narrow-angle light distribution, the incident surface 131a _F2 is a concave lens Te, in which the right of the light beam from the optical axis 110a of the central ray l _c a wide angle light distribution.

With the above configuration, if there is a light irradiation surface on the right side of FIG. 16 and FIG. 17, the right side of the light beam from the optical axis 110a of the central ray l _c is from LED lighting apparatus 100F because it is light distribution in a wide angle with distance has a peak illuminance in a relatively close, left of the light beam from the optical axis 110a of the central ray l _c, the distance is relatively far position from the LED lighting apparatus 100G because it is light distribution in the narrow angle The light is distributed so as to have a peak of illuminance. Therefore, the illuminance at a relatively far position can be improved as compared with the first embodiment.

[Modification 1]
FIG. 18 is a longitudinal cross-sectional view illustrating a schematic configuration example of a lighting device as a first modification of the second embodiment. FIG. 19 is a schematic view showing an optical path of light emitted from the LED light source 110 of the illumination device shown in FIG.

The illumination device 100G of Modification 1 includes an optical member 130G that is different from the LEG illumination device 100A, and the other configurations are the same. The optical member 130G is different shapes of the incident surface 131a _G is an incident surface 131a _A of the optical member 130A, while the incident surface 131a _A is concave, incident surface 131a _G is a convex shape, the central ray l _c is condensed so as to enter the exit surface 131b _G. The optical member 130G is different in the shape of the exit surface 131b _{G from} the exit surface 131b of the optical member 130A and the exit surface 131b is flat, whereas the exit surface 131b _G is provided on the inner diameter side of the exit surface 132d. The bottom surface of the cylindrical concave portion has a shape in which the depth of the bottom surface becomes shallower in a curved or linear shape from the left side to the right side of the drawing, and the condensed central light beam l _c is wide-angled on the right side in the drawing. Is emitted.

With the above configuration, the same effects as those of the second embodiment can be obtained.
[Modification 2]
FIG. 20 is a longitudinal cross-sectional view illustrating a schematic configuration example of a lighting device serving as a second modification of the second embodiment. FIG. 21 is a schematic diagram showing an optical path of light emitted from the LED light source 110 of the illumination device shown in FIG.

The illumination device 100H of Modification 2 includes an optical member 130H different from the LED illumination device 100A, and the other configurations are the same. The optical member 130H is different shapes of the incident surface 131a _H is an incident surface 131a _A of the optical member 130A, while the incident surface 131a _A is concave, incident surface 131a _H is a convex shape, the central ray l the _c is for the light collector to be incident on the reflecting surface 131b _H.

The optical member 130H is different from the optical member 130A having an exit surface 131b of the plane, focused central ray _{l c} the direction of the light irradiation surface of the central ray _{l c} which is reflected a total reflection to the reflecting surface 131b _H And a light exit surface 131c _H that exits from the light source.

With the above structure, it is possible to light distribution of the central ray l _c a wider angle compared to the embodiment and Modification 1 of the second embodiment.

  In addition, this invention is not limited to the said embodiment and said Example, A various deformation | transformation is possible within the range which does not change the summary of invention. For example, the LED lighting devices 100A-100H (collectively LED lighting devices 100) are arranged on the upper side in addition to being arranged on the lower side inside the outer frame portion 5 of the internal lighting signboard 2 as shown in FIG. Also good.

  FIG. 22 is a schematic perspective view showing another example of the configuration of the internal lighting signboard using the illumination device.

  As shown in FIG. 22, the interior lighting signboard 2 </ b> A arranges the LED lighting devices 100 on the upper side and the lower side inside the outer frame portion 5, thereby supplementing each other with illuminance that monotonously decreases with respect to the distance from the LED lighting device 100. It is possible to suppress illuminance unevenness of the panel portions 3 and 4.

DESCRIPTION OF SYMBOLS 1 LED element 2 Internal illumination signboard 3, 4 Panel part 5 Outer frame part 30, 40 Light irradiation surface 100 LED illumination apparatus 100A-100H LED illumination apparatus 110 LED light source 110a Optical axis 111 Copper block 117 Radiator 130A-130H Optical member 131a _A entrance surface 131a _B entrance surface 131a _C entrance surface 131a _D entrance surface 131a _E entrance surface 131a _F1 entrance surface 131a _F2 entrance surface 131a _G entrance surface 131a _H entrance surface 131b exit surface 131b _D exit surface 131b _E exit surface 131b _G exit surface 131b _H reflecting surface 131c _E emitting surface 131c _H emitting surface 132b incident surface 132c reflecting surface 132d emitting surface

Claims (5)

A semiconductor light emitting device;
A first shaping unit that distributes light from a first emission surface at a wide angle in the optical axis direction of the semiconductor light emitting device with a light beam emitted from the semiconductor light emitting device and incident on a first incident surface formed on the bottom surface of the recess as a central light beam When the emitted from the semiconductor light emitting device, the optical axis direction from the second emission surface as a peripheral light flux to the light beam incident on the second incident face to form a side by total reflection to condensed by the reflecting surface of the concave portion An optical member having a second shaping unit that emits light having a narrower light distribution angle than the central light flux ,
The first emission surface of the first shaping unit and the second emission surface of the second shaping unit are planes having normal lines parallel to the optical axis,
The second shaping unit has a trough of illuminance at a first distance when irradiating light emitted from the second emission surface on an irradiation surface parallel or substantially parallel to the optical axis direction,
The first incident surface of the first shaping unit complements the valley of the illuminance of the second shaping unit to the first distance when the irradiation surface is irradiated with light emitted from the first emission surface. An illumination device designed to have a concave aspherical shape so as to have a peak of illuminance. The lighting device according to claim 1, wherein the second shaping unit emits light parallel or substantially parallel to the optical axis from the second emission surface . 3. The lighting device according to claim 1, wherein the semiconductor light emitting element is provided with a phosphor that is excited by a first color light emitted from the semiconductor light emitting element to emit a second color light. A first shaping unit that distributes light from a first emission surface at a wide angle in the optical axis direction of the semiconductor light-emitting element as a central light beam emitted from the semiconductor light-emitting element and incident on a first incident surface formed on the bottom surface of the recess; ,
Said emitted from the semiconductor light emitting element, the center from the second emission surface as a peripheral light flux to the light beam incident on the second incident face to form a side by total reflection to condensed by the reflecting surface of the concave portion in the optical axis direction A second shaping unit that emits light having a narrower light distribution angle than the luminous flux ,
The first emission surface of the first shaping unit and the second emission surface of the second shaping unit are planes having normal lines parallel to the optical axis,
The second shaping unit has a trough of illuminance at a first distance when irradiating light emitted from the second emission surface on an irradiation surface parallel or substantially parallel to the optical axis direction,
The first incident surface of the first shaping unit complements the valley of the illuminance of the second shaping unit to the first distance when the irradiation surface is irradiated with light emitted from the first emission surface. An optical member designed in a concave aspherical shape so as to have a peak of illuminance . A first shaping unit that distributes light at a wide angle in the optical axis direction of the semiconductor light emitting element as a central light beam emitted from the semiconductor light emitting element;
Design of an optical member having a second shaping unit that condenses a peripheral light beam emitted from the semiconductor light emitting element to the periphery of the central light beam and emits light having a narrower light distribution angle than the central light beam in the optical axis direction A method,
When the light emitted from the second shaping unit is irradiated on an irradiation surface parallel or substantially parallel to the optical axis direction, obtaining a first distance of the valley of illuminance;
When the irradiation surface is irradiated with light emitted from the first shaping unit, the first shaping unit has an illuminance peak that complements the illuminance valley of the second shaping unit at the first distance. Designing the stage,
An optical member design method including: