JP2013235820A - Light distribution decentralized control type led lighting device and lighting method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting method capable of attaining illumination for securing illumination intensity required for a lighting target and being useful and restraining color unevenness.SOLUTION: A lighting method uses an LED lighting device having a plurality of LED lighting devices including light-distributing angle control lenses for controlling light in designated light-distributing angles by receiving light emitted from light sources, and microlens arrangement parts including a plurality of microlenses and dispersing light by receiving the emitted light wherein the light-distributing angles are controlled. Here, each microlens is an anisotropic microlens wherein a curvature radius R and/or a pitch P are different in a designated direction within a lens arrangement surface. The light emitted from the plurality of LED lighting devices in the LED lighting device are joined together in order to form irradiation light having a lighting zone part with a fixed width, and the irradiation light is irradiated to the lighting target surface. Thus, a lighting shape having the fixed width can be adapted to the lighting target.

Description

  The present invention relates to a lighting technique using a light emitting diode (LED).

  In recent years, LED lighting devices using LEDs as light sources have been developed, and their commercialization is progressing at a rate to replace conventional lighting devices such as incandescent lamps and fluorescent lamps. The LED lighting device can achieve low power consumption that surpasses that of fluorescent lamps that have been required to have high luminous efficiency, and has a longer lifetime. Furthermore, there is no need for specific harmful substances such as mercury that are restricted in use by the RoHS Directive (2006, European Union), which is advantageous in terms of measures against environmental problems.

  In this LED illuminating device, it is very important to control the light distribution in order to realize illumination light having illumination range and illuminance suitable for the illumination target.

  As an LED illuminating device that adjusts the light distribution characteristics, Patent Literature 1 discloses a luminaire that includes first and second LEDs arranged in rows on two arrangement surfaces of a columnar base. It is disclosed. As an example of lighting, an internal space of a road (a tunnel passage that accommodates communication cables, power transmission cables, gas pipes, etc. and is large enough for a person to enter for work) is taken as an example. Here, an overlapped bright portion of the bright portion of the surface to be illuminated by the illumination light from the first LED and the bright portion of the surface to be illuminated by the illumination light from the second LED is generated on the surface to be illuminated in the road. Light distribution is adjusted.

  Patent Document 2 discloses an LED illumination apparatus that illuminates the vicinity of the apparatus with an LED having a large emission angle and illuminates a distant area with an LED having a small emission angle. In this apparatus, an LED having a small emission angle is arranged at the upper part of the light source plate, while an LED having a large emission angle is arranged at the lower part of the light source plate.

  Furthermore, Patent Document 3 discloses an LED lighting device installed in a place that requires uniform illuminance or luminance distribution on the floor surface. In this apparatus, two or more LED illumination unit modules in which a plurality of LED light sources are arranged on a substantially semi-cylindrical inner curved surface or outer curved surface are arranged in the longitudinal direction.

  Patent Document 4 discloses an LED illumination device having a reflector that reflects light emitted from an LED light source. Patent Document 4 describes an embodiment in which this LED lighting device is used as a street lamp.

  Furthermore, Patent Document 5 includes a light source composed of a plurality of LEDs and a plurality of convex lenses, each positioned on each LED, and changes the distance and inclination angle of the convex lens with respect to the LEDs to change the light emitted from the light source. An LED lighting device that changes light distribution characteristics is disclosed.

JP 2010-40247 A JP 2008-4519 A Special table 2011-521422 gazette JP 2011-40196 A JP 2010-92700 A

  As described above, conventionally, various devices have been devised in order to control the light distribution characteristics of irradiation light in an LED lighting device. However, it has still been difficult to realize lean illumination in which necessary illuminance is ensured according to the illumination target.

  For example, when controlling the light distribution characteristics of the emitted light from the LED using an ordinary circular convex lens as in Patent Document 4, the illuminance of the irradiated light has a concentric intensity distribution around the maximum illuminance point. Therefore, the illumination range is limited to a circle. As a result, for example, when the object to be illuminated is a quadrangular (rectangular) area as seen in a work / exhibition space, etc., it has a limited width such as a road (passage) and a road (tunnel passage). In the case of a rectangular region extending in the longitudinal direction, it becomes difficult to perform illumination without waste while ensuring necessary illuminance.

  That is, in this case, if the circular illumination range is completely taken into this quadrangular area, the illuminance at the corners or sides of the quadrangular area is insufficient. On the other hand, if this circular illumination range is taken larger and the rectangular area is taken in, a large amount of power must be supplied to the LED illumination device, and the outside of the rectangular area is unnecessarily illuminated, which is contrary to low power consumption. .

  In particular, when illuminating a road, since the street lamp is installed on the side of the road, the area outside the road is also illuminated, resulting in wasteful power consumption. In addition, it may be a problem in the living environment to illuminate an area outside the road where illumination is not necessary, for example, a private house site.

  With respect to such a problem, Patent Document 1 describes securing a necessary bright portion in the road, but that alone does not realize a wasteful illumination area according to the irradiation target. . Further, Patent Document 2 describes that a predetermined range is uniformly irradiated with sufficient brightness, and Patent Document 3 also describes that the illuminance or luminance distribution is made uniform. Furthermore, Patent Document 4 intends to expand the illumination range and effectively use the emitted light. However, similarly to Patent Document 1, it is clearly difficult to realize a lean illumination in which a necessary illuminance is ensured according to an illumination target only with these technologies.

  Furthermore, the problem of color unevenness peculiar to the LED lighting device is still serious particularly in the lighting device using the white LED light source using the phosphor.

  Many white LED light sources include a blue LED chip and a yellow phosphor, and the blue emitted light from the blue LED chip and the yellow fluorescence generated by exciting the yellow phosphor by the emitted light (complementary light of blue light). To obtain white light. At this time, the degree of white is determined by the light quantity ratio between blue light and yellow light. As a result, for example, just above the blue LED chip, the ratio of blue light is increased to obtain blueish white light, and the tendency to change to yellowish white light as it moves away from the position directly above toward the periphery of the light source Occurs.

  Furthermore, in order to control the light distribution characteristics of the radiated light from such a light source, if the radiated light is passed through an optical system such as a convex lens, the difference in the color mixture ratio between blue light and yellow light is further expanded. . As a result, for example, the vicinity of the center of the irradiation light emitted from this optical system becomes a pale color, and a yellowish ring may be visible around the periphery, resulting in color unevenness. However, in the conventional techniques represented by Patent Documents 1 to 5 described above, it has not been sufficient to cope with such a color unevenness problem in realizing an illumination range corresponding to an illumination target.

  Therefore, the present invention provides an LED illumination device capable of realizing illumination with no illuminance required for each illumination target and suppressing color unevenness, and an illumination method using the LED illumination device. The purpose is to do.

According to the present invention, an illumination method using an LED illumination apparatus including a plurality of LED illumination devices,
LED lighting devices
A light source with a light emitting diode chip;
A light distribution angle control lens unit that receives the emitted light from the light source and controls it to a predetermined light distribution angle;
Including a plurality of microlenses arranged with the emission positions of the light distribution angle control lens unit as lens arrangement surfaces, and a microlens arrangement unit that receives and disperses the radiation light whose light distribution angle is controlled,
The plurality of microlenses have a radius of curvature R, a pitch P that is a distance between the lens vertices of the adjacent microlenses, or both the radius of curvature R and the pitch P. An anisotropic microlens that differs between the direction of one axis and the direction of an axis perpendicular to the axis, and the direction of the axis connecting the lens vertices in the lens arrangement plane with respect to the pitch P,
The lighting method is
Combining light emitted from a plurality of LED lighting devices to form illumination light having an illumination region portion of a certain width,
An illumination method is provided that irradiates a surface to be illuminated with irradiation light. Here, it is also preferable to irradiate the illumination target surface with the optical axis of the illumination light from the LED illumination device inclined with respect to the normal line of the illumination target surface.

  In the illumination method according to the present invention, in the microlens array portion of the plurality of LED illumination devices used for illumination, the curvature radius R and pitch P of the microlens or both the curvature radius R and pitch P are predetermined in the lens array plane. Different values are set and controlled in different directions. Thereby, the irradiation light which has an illumination area | region part of a fixed width | variety can be formed. As a result, it is possible to adapt the illumination shape having a certain width to the illumination target, so that it is possible to realize a lean illumination in which the illuminance required according to the illumination target is ensured. In addition, since the emitted light whose light distribution angle is controlled by the light distribution angle control lens unit is dispersed by the micro lens array unit, illumination with suppressed color unevenness is realized.

In the illumination method according to the present invention, a plurality of LED illumination devices are arranged side by side along the longitudinal direction of the illumination target surface at a position facing the illumination target surface,
It is also preferable that the illumination light from each of the plurality of LED illumination devices is arranged in the longitudinal direction while being adjacent to each other or partially overlapped to irradiate the illumination target surface. Here, examples of the illumination target surface include a road surface of a road or a passage, or a floor surface and a side surface of a road (tunnel passage).

In the illumination method according to the present invention, the LED illumination apparatus includes a plurality of device groups including a plurality of LED illumination devices,
The optical axis of one device group and the optical axis of the other device group have different directions from each other in the longitudinal vertical plane including the longitudinal axis and the normal line of the illumination target surface. It is also preferable to irradiate the illumination target surface with irradiation light and irradiation light from the other device group. By using such an LED illumination device, it is possible to irradiate the irradiation target surface with irradiation light having a sufficiently large light distribution angle and sufficiently high illuminance while controlling the illumination shape.

Furthermore, in the illumination method according to the present invention, the LED illumination apparatus includes a plurality of device groups including a plurality of LED illumination devices,
In a state in which the optical axis of one device group and the optical axis of the other device group have different directions in a cross section perpendicular to the longitudinal axis of the illumination target surface, the irradiation light from the one device group It is also preferable to irradiate the illumination target surface with irradiation light from the other device group.

  In the embodiment including the plurality of device groups, it is also preferable that the plurality of LED lighting devices included in one device group form one row. Alternatively, a plurality of LED lighting devices included in one device group and a plurality of LED lighting devices included in another device group may be alternately arranged or mixed to form one row. preferable. Furthermore, for these arrangements, this single row may also have a direction in a longitudinal vertical plane that includes the longitudinal axis and normal of the surface to be illuminated, or a direction in a cross-section that is orthogonal to the longitudinal axis of the surface to be illuminated. preferable.

Moreover, in the illumination method according to the present invention, the plurality of LED illumination devices are installed at a predetermined interval above at least one end in the width direction of the illumination target surface,
The illumination light is irradiated with the illumination light in a state where the optical axis of the illumination light from each of the plurality of LED illumination devices is inclined with respect to the normal line of the illumination target surface in a cross section orthogonal to the longitudinal axis of the illumination target surface. It is also preferable to irradiate the target surface. At this time, it is also preferable to make the width of the illumination shape in the width direction of the illumination target surface substantially coincide with the width of the illumination target surface. Thereby, in the width direction of the surface to be illuminated, necessary illumination is ensured and illumination without waste is realized.

Further, in the embodiment in which the width of the illumination shape is substantially matched with the width of the illumination target surface, the height from the illumination target surface to the LED illumination device is h, the width of the illumination target surface is W, and the LED illumination device The angle θ _el formed by the optical axis of the irradiation light and the normal of the illumination target surface, where α is the irradiation angle of the irradiation light from
W = h · tan (α / 2 + θ _el ) + h · tan (α / 2−θ _el )
It is also preferable to irradiate the illumination target surface with irradiation light from a plurality of LED illumination devices.

Moreover, in the illumination method according to the present invention, the LED illumination apparatus includes a plurality of device groups including a plurality of LED illumination devices,
The first device group illuminates a region (region immediately below the device) directly facing the device on the illumination target surface,
The second device group has an optical axis that is at a larger angle with respect to the normal of the illumination target surface as compared to the optical axis of the first device group, and further outside the outer region. It is also preferred to illuminate the area.

In the embodiment including the plurality of device groups, the illumination target surface is a portion of the inner surface including the side surface in the passage,
A plurality of LED lighting devices included in the third device group form a predetermined angle with respect to a plane defined by the optical axis of the first device group and the optical axis of the second device group. It is also preferable to irradiate a region within a predetermined range on the side surface of the passage having an inclined optical axis.

Furthermore, in the embodiment including the plurality of device groups described above, the illumination target surface is a portion of the inner surface including the side surface in the passage,
A plurality of LED illumination devices included in a plurality of device groups provided in the LED illumination apparatus are illuminated with a longitudinal axis in the apparatus (for example, the x axis in FIG. 25A) and the object directly facing the apparatus. It is inclined at a predetermined angle (for example, θ _SIDE ) with respect to a plane (for example, zx plane) defined by an axis (for example, the z axis in FIG. 25A) extending from the apparatus toward the surface area. It is also preferable to irradiate a region within a predetermined range on the side surface of the passage.

  Furthermore, in the illumination method according to the present invention, the LED illumination apparatus includes a light diffuser on the emission side of at least one LED illumination device, and passes light emitted from the at least one LED illumination device through the light diffuser. It is also preferable to irradiate with diffusion. It is also preferable to increase the illuminance in a region (region immediately below the device) directly facing the device on the illumination target surface by passing the emitted light through the light diffuser.

  Furthermore, in the illumination method according to the present invention, a plurality of LED illumination devices are arranged side by side along the longitudinal direction of the surface to be illuminated, and after adjusting the haze value Hz of the light diffuser in each LED illumination device, the emitted light is emitted as light. By passing through the diffuser, the illuminance in the intermediate area between the area directly facing the apparatus on the surface to be illuminated (the area directly under the apparatus) is substantially equal to the illuminance when the light diffuser is not used. It is also preferable to do. Here, it is also preferable to adjust the haze value of the light diffuser to a value of 70% or more and less than 90%.

Furthermore, in the illumination method according to the present invention, when the height from the illumination target surface to the LED illumination device is h, and the installation interval of the plurality of LED illumination devices is D, the irradiation angle β of the irradiation light from the LED illumination device is
β ≧ 2 · tan ⁻¹ (D / (2h))
It is also preferable to irradiate the illumination target surface with irradiation light from a plurality of LED illumination devices.

  Furthermore, in the illumination method according to the present invention, the illumination shape of the irradiation light having the illumination region portion of a certain width is made into a substantially rectangular shape or a substantially square shape in which the area ratio with respect to the circumscribed rectangle or square is 0.9 or more. It is also preferable.

According to the present invention, there is further provided an LED lighting apparatus including a plurality of LED lighting devices,
LED lighting devices
A light source with a light emitting diode chip;
A light distribution angle control lens unit that receives the emitted light from the light source and controls it to a predetermined light distribution angle;
Including a plurality of microlenses arranged with the emission positions of the light distribution angle control lens unit as lens arrangement surfaces, and a microlens arrangement unit that receives and disperses the radiation light whose light distribution angle is controlled,
The plurality of microlenses have a radius of curvature R, a pitch P that is a distance between the lens vertices of the adjacent microlenses, or both the radius of curvature R and the pitch P. An anisotropic microlens that differs between the direction of one axis and the direction of an axis perpendicular to the axis, and the direction of the axis connecting the lens vertices in the lens arrangement plane with respect to the pitch P,
Provided is an LED illumination apparatus, wherein the LED illumination devices are arranged such that emitted light from each of the LED illumination devices forms illumination light having an illumination region portion having a constant width. Is done.

  The LED illumination apparatus according to the present invention includes a plurality of device groups including a plurality of LED illumination devices, and the optical axis of one device group and the optical axes of the other device groups may have different directions. preferable. In this case, it is also preferable that the plurality of LED lighting devices included in one device group form one row. Alternatively, a plurality of LED lighting devices included in one device group and a plurality of LED lighting devices included in another device group are alternately arranged or mixed to form one row. It is also preferable.

  Moreover, in the LED lighting apparatus according to the present invention, the plurality of LED lighting devices included in one device group and the plurality of LED lighting devices included in the other device group each have an emission surface of less than 180 degrees or It is also preferable that they are arranged so as to form a predetermined angle exceeding 180 degrees.

  Furthermore, in the LED lighting device according to the present invention, it is also preferable that the light distribution angle control lens unit and the micro lens array unit in the plurality of LED lighting devices included in one device group are integrally formed.

Further, in the LED illumination device according to the present invention, the first device group is installed so as to illuminate an outer region of a region (region immediately below the device) directly facing the device on the illumination target surface,
The second device group has an optical axis that forms a larger angle with respect to the direction toward the region directly facing the device as compared with the optical axis of the first device group, and It is also preferably arranged to illuminate a further outer area of the area.

  Furthermore, in the embodiment having the first and second device groups, the plurality of LED illumination devices included in the third device group include the optical axis of the first device group and the second device group. It is also preferable to have an optical axis that is inclined at a predetermined angle with respect to a plane defined by the optical axis.

  Further, in an embodiment having a plurality of device groups, a plurality of LED illumination devices included in the plurality of device groups includes a longitudinal axis in the apparatus and a region of the illumination target surface directly facing the apparatus (the apparatus It is also preferable to have an optical axis inclined at a predetermined angle with respect to a plane defined by an axis extending from the apparatus toward the region immediately below.

  Furthermore, the LED illumination apparatus according to the present invention further includes a light diffuser that is provided on the emission side of the at least one LED illumination device and diffuses and emits the emitted light from the at least one LED illumination device. It is also preferable. Here, the haze value of the light diffuser is preferably 70% or more and less than 90%.

  The LED illumination device and the illumination method using the LED illumination device according to the present invention can realize illumination that ensures a sufficient illuminance depending on an illumination target and is free from color unevenness.

It is the perspective view, side sectional view, bottom view, and top view which show one Embodiment of the LED lighting device with which the LED lighting apparatus of this invention is equipped. FIG. 6 is a top view and a side cross-sectional view for explaining a microlens array in the microlens array section 131. FIG. It is a cross-sectional schematic for demonstrating the light distribution angle control in a light distribution angle control lens part, and the graph which shows the example of control of ratio P / R in a micro lens arrangement | sequence part. In the graph which shows the illuminance distribution in x'y 'plane in Example 1, the graph which shows the illuminance distribution in x'y' plane in Example 2, and in the x'y 'plane in Example 3-3 It is a graph which shows illuminance distribution. It is the front view, sectional drawing, and rear view which show one Embodiment of the LED lighting apparatus by this invention. It is a perspective view which shows roughly two embodiment which concerns on the illumination shape of the LED lighting apparatus by this invention. It is a perspective view showing roughly one embodiment in the lighting method by the LED lighting device of the present invention. It is the schematic for demonstrating other embodiment in the illumination method by the LED lighting apparatus of this invention. It is the schematic for demonstrating embodiment which inclines the optical axis of irradiated light with respect to the normal line of a road surface shown in FIG. 8, and the schematic which shows a mode that the LED lighting apparatus was installed in the way. 9A is a schematic diagram for explaining the setting of the angle for matching the width of the illumination area with the width of the road surface and the setting of the position of the LED lighting device, and the illumination areas by the irradiation light are adjacent to each other. It is a schematic diagram for explaining the setting of the irradiation angle of irradiation light for arranging in the longitudinal direction while partially overlapping. It is the front view, sectional drawing, and side view which show other embodiment of the LED lighting apparatus by this invention. It is the front view and sectional drawing which show other embodiment of the LED lighting apparatus by this invention. It is the front view and sectional drawing which show other embodiment of the LED lighting apparatus by this invention. It is the front view and sectional drawing which show other embodiment of the LED lighting apparatus by this invention. It is the schematic for demonstrating embodiment which concerns on installation of the illuminating device in the longitudinal direction of a road (or passage) or a road. It is the schematic for demonstrating other embodiment which concerns on the illumination method in the longitudinal direction of a way. It is a top view, a front view, a bottom view, and a sectional view showing an LED lighting device used in an example in which a road is illuminated by the lighting method of the present invention. It is the schematic which shows the orientation of the LED lighting device in an LED lighting apparatus, and the schematic which shows the direction of the optical axis of an LED lighting device. It is a graph which shows the characteristic of the emitted light radiated | emitted from a LED lighting device. It is a graph which shows the illuminance distribution at the time of illuminating the road with an LED illuminating device. It is a graph which shows the illuminance distribution at the time of illuminating the road with an LED illuminating device. It is a graph which shows the illumination intensity distribution at the time of illuminating the way 6 with a fluorescent lamp (20W). It is the graph which displayed in three dimensions the illumination intensity distribution on the floor surface and side surface of a way in a present Example (LED lighting apparatus 97) and a comparative example (fluorescent lamp). It is sectional drawing which shows the change aspect of a LED lighting apparatus. It is the front view and sectional drawing which show the LED lighting apparatus as one Embodiment of this invention, and the schematic which shows orientation of the LED lighting device in an apparatus. It is the schematic which explains the effect | action of the graph which shows the relationship between the angle which a line-of-sight direction makes with respect to an emitted light, and the light beam quantity which feels "dazzle", and a light-diffusion sheet. It is a graph which shows the illumination intensity distribution of the illumination by an LED illuminating device in the case where a light-diffusion sheet is used and the case where it is not used. A graph showing the illuminance distribution of the illumination by the LED illumination device when the uniformizing optical body (lens system) is installed and using the light diffusion sheet, and the uniformizing optical body (lens system) 6 is a graph showing the illuminance distribution of illumination by the LED illumination device when the light diffusing sheet is used and when it is not used.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated in detail, referring an accompanying drawing. In the drawings, the same elements are denoted by the same reference numerals. In addition, the dimensional ratios in the components in the drawings and between the components are arbitrary for easy viewing of the drawings.

[LED lighting device]

  FIG. 1 is a perspective view, a side sectional view, a bottom view, and a top view showing an embodiment of an LED lighting device provided in the LED lighting device of the present invention. In each figure, an x'y'z 'coordinate system that is an index of the orientation of the device is shown.

  FIG. 1A shows an LED lighting device 10 as one embodiment. FIG. 1B shows a side cross section of the LED lighting device 10 in which the device central portion is cut by the z′x ′ plane. According to both figures, the LED lighting device 10 includes a base 11, an LED light source 12 installed on the base 11, a homogenizing optical body 13 positioned at least above the LED light source 12, and a homogenizing optical body. 13 is provided with legs 14 for installing the base 13 on the base 11.

  The homogenizing optical body 13 is a plastic material such as acrylic resin, polycarbonate resin, cycloolefin polymer resin, cyclic olefin resin, optical special polyester resin, optical silicone resin or high density polyethylene resin, or transparent optical glass or fluorescent glass. Etc. are formed using a ceramic material. The LED light source 12 is installed and fixed on the base 11, is electrically connected to the wiring provided inside or on the surface of the base 11, and receives power supply from an external power source.

  The LED light source 12 includes a light emitting diode chip (LED chip) that emits light of a first wavelength, and emits light of mixed colors of at least light of the first wavelength and light of a second wavelength different from the first wavelength. It is. The LED light source 12 is, for example, an LED chip that emits light of a first wavelength (for example, blue light) and a resin that covers the light emitting surface of the LED chip, and absorbs light of the first wavelength. And a resin containing a phosphor that emits light of the second wavelength (for example, yellow light) as fluorescence. Since the above-described uniformizing optical body 13 promotes color mixing and color uniformity of irradiation light, it is possible to suppress the occurrence of color unevenness such as a yellow ring due to the LED light source 12.

  Similarly, according to FIGS. 1A and 1B, the homogenizing optical body 13 is positioned at least above the LED light source 12 and receives the emitted light from the LED light source 12 to promote color mixing and color uniformity. It is an optical system that emits the irradiated light. The homogenizing optical body 13 is installed on the base 11 with four legs 14 in this embodiment, but the installation method is not limited to this.

  The homogenizing optical body 13 includes a light distribution angle control lens unit 130 and a micro lens array unit 131. The light distribution angle control lens unit 130 has an incident surface (incident inner surface) 130cs on which the emitted light (mixed color light) from the LED light source 12 is collected after being incident, and the incident emitted light (mixed color light) is predetermined. Control the light distribution angle to a value within the range. As will be described later, this light distribution angle is preferably controlled to a value within a range from 5 degrees (°) to 40 ° as a full width at half maximum.

  Further, in the present embodiment, the light distribution angle control lens unit 130 includes a recess 130c that includes at least the light emitting surface 12e of the LED light source 12 (substantially the entire LED light source 12 in the present embodiment). Thereby, the light distribution angle control lens unit 130 can receive the emitted light from the LED light source 12 with high efficiency.

  The concave portion 130c includes an incident inner surface 130cs having a convex lens surface shape. Thereby, the radiated light (mixed color light) from the LED light source 12 enters the incident inner surface 130cs and then is condensed. As a result, the light distribution angle of the radiated light (mixed color light) propagating in the diverging direction can be controlled to a value within a predetermined range. The incident inner surface 130cs is not limited to the convex lens surface shape, and may be a surface that is incident at an incident angle such that the emitted light (mixed color light) from the LED light source 12 is collected. For example, depending on the set light distribution angle, it may be substantially planar. Further, the recess 130 c includes an inner wall surface 130 cw provided at a position surrounding the LED light source 12. Thereby, the light distribution angle control lens unit 130 can receive the emitted light (mixed color light) from the LED light source 12 through the inner wall surface 130cw.

  The microlens array unit 131 transmits light (mixed color light) whose light distribution angle is controlled from the light distribution angle control lens unit 130 via an emission position on the side opposite to the incident inner surface 130cs in the light distribution angle control lens unit 130. It is an optical part that receives light and disperses it to promote color uniformity. Here, the emission position of the light distribution angle control lens unit 130 (boundary with the minute lens array unit 131) is a planar lens array surface 131a in the present embodiment. Therefore, the light distribution angle control lens unit 130 can be regarded as a surface light source that emits light whose light distribution angle is controlled from the emission position surface, while the microlens array unit 131 is distributed from the surface light source. The light whose light is controlled can be regarded as a dispersion control optical system that receives light through the lens array surface 131a.

  Further, as shown in FIG. 1D, which is a top view, the microlens array unit 131 includes a plurality of microlenses 131m arranged with the lens array surface 131a as a bottom surface. The arrangement of the micro lenses 131m will be described in detail later with reference to FIG.

  It is preferable that the light distribution angle control lens unit 130 and the minute lens array unit 131 or these portions and the leg portion 14 are formed integrally. As this formation method, an optically transparent resin such as an acrylic resin, a polycarbonate resin, a cycloolefin polymer resin, a cyclic olefin resin, an optical special polyester resin, an optical silicone resin, or a high-density polyethylene resin, Alternatively, a method of injecting and curing transparent optical glass, fluorescent glass, or the like can be employed.

[Micro lens array]

  FIGS. 2A and 2B are a top view and a side sectional view for explaining the microlens array in the microlens array section 131. FIG.

  FIG. 2 (A1) shows a hexagonal array of a plurality of microlenses 131m. FIG. 2 (A2) shows a side cross section of the hexagonal array taken along the z'x 'plane. According to FIGS. 2A1 and 2A2, the hexagonal array is an array in which a plurality of microlenses 131m are arranged so that the lens apexes 131mt form a hexagonal lattice. Each micro lens 131m has a shape that becomes a part of a micro hemisphere or a semi-spheroid (semi-elliptic sphere). As a modification, the surface shape of the minute lens 131m can be an aspherical surface.

  As shown in FIGS. 2A1 and 2A2, each microlens 131m has a bottom surface as a lens arrangement surface 131a (an emission position of the light distribution angle control lens unit 130), and a light emitting surface (an emission side surface). Let R be the radius of curvature. Here, since the light emitting surface is convex in the light traveling direction (+ z ′ direction), its radius of curvature is originally a negative value. However, for convenience of calculation and the like, hereinafter, the absolute value is taken as an R value, and this R value is taken as a radius of curvature. Further, let P be the distance (pitch) between the lens apexes 131 mt of the adjacent minute lenses 131 m.

Here, in the arrayed microlenses 131m, the curvature radius R, the pitch P, or both the curvature radius R and the pitch P are one axis connecting the vertexes of the lens in the lens array surface 131a with respect to the curvature radius R. With respect to the pitch P between the direction of the (y ′ axis) and the direction of the axis (x ′ axis) perpendicular to this axis (the y ′ axis and the x ″ axis) connecting the lens vertices in the lens array surface 131a. ) Different in each direction. Specifically, in FIG. 2A1, the radius of curvature R _{y ′} in the y′-axis direction is larger than the radius of curvature R _{x ′} in the x′-axis direction, and the pitch P _{y in} the y′-axis direction is larger. _“ Is larger than the pitch P _{x” in} the x ″ axis direction.

Here, the arrangement of the microlenses 131m is considered using the ratio P / R of the pitch P and the radius of curvature R as a parameter. In FIG. 2 (A1), there is a triple point where the three microlenses 131m overlap each other, and if the interval between the microlenses 131m is further increased (the ratio P / R in each axial direction connecting the lens apexes increases). Then, there is a limit state in which a region other than the microlens 131m is formed in the lens array surface 131a. In other words, in a state where the ratio P / R has an upper limit value that does not form a region that is not the minute lens 131m in the lens array surface 131a in each axial direction (y ′ axis, x ″ axis) connecting the lens apexes. is there. Here, the curvature radius R in the ratio P / R in the x ″ axis direction is the curvature radius R _{x ″ in} the x ″ axis direction. When the plurality of microlenses 131m are arranged in a regular hexagon and the bottom surface of the lens is circular (R _{y ′} = R _{x ′} ), the upper limit value of the ratio P / R is 1.73 (√3). Become.

  On the other hand, when the ratio P / R decreases in each axial direction and the interval between the microlenses 131m becomes narrow, the overlapping portion of the adjacent microlenses 131m increases, and the degree of unevenness of the light emitting surface as the entire microlens array portion 131 increases. Decrease. As a limit, at the ratio P / R = 0, the light emitting surface of the microlens array portion 131 is a surface along the lens array surface 131a having no unevenness. As will be described in detail later with reference to FIG. 3, the ratio P / R is preferably 0.4 or more and not more than the above upper limit value in this hexagonal arrangement. By controlling the ratio P / R in this way, it is possible to obtain irradiation light having a desired illuminance in which the mixed color light emitted from the LED light source 12 is sufficiently uniformed.

  FIG. 2B shows a quadrangular arrangement of a plurality of microlenses 131m. According to the figure, the square array is an array in which a plurality of microlenses 131m are arranged such that the lens apexes 131mt form a square lattice or a rectangular lattice. Details of the individual microlenses 131m are the same as those shown in FIGS. 2A1 and 2A2.

In the arrayed microlenses 131m, the radius of curvature R and the pitch P, or both the radius of curvature R and the pitch P, with respect to the radius of curvature R, one axis (x ′) connecting the lens vertices in the lens array surface 131a. Between the direction of the axis) and the direction of the axis perpendicular to this axis (y ′ axis), the pitch P is the direction of each axis (x ′ axis and y ′ axis) connecting the lens vertices in the lens array surface 131a. Is different. Specifically, in FIG. 2B, the curvature radius R _{y ′} in the y′-axis direction is larger than the curvature radius R _{x ′} in the x′-axis direction, and the pitch P _{y in} the y′-axis direction is larger. _' Is larger than the pitch P _{x' in the x-} axis direction.

  Here, even in the quadrangular arrangement, the arrangement of the microlenses 131m is considered using the ratio P / R of the pitch P and the radius of curvature R as a parameter. In FIG. 2B, there are four points where four microlenses 131m are superimposed, and when the interval between the microlenses 131m is further increased (the ratio P / R in each axial direction connecting the lens apexes increases). Then, there is a limit state in which a region other than the microlens 131m is formed in the lens array surface 131a. In other words, the ratio P / R is in a state of taking an upper limit value in which a region other than the microlens 131m is not formed in the lens arrangement surface 131a in each axial direction (x ′ axis, y ′ axis) connecting the lens apexes. .

When the plurality of microlenses 131m are arranged in a square pattern and the bottom surface of the lens is circular (R _{y ′} = R _{x ′} ), the upper limit value of this ratio P / R is 1.41 (√2). . Further, as will be described later with reference to FIG. 3, the ratio P / R is preferably 0.4 or more and not more than the above upper limit value even in this square array. By controlling the ratio P / R in this way, it is possible to obtain irradiation light having a desired illuminance in which the mixed color light emitted from the LED light source 12 is sufficiently uniformed.

[Light distribution angle / ratio P / R control]

  FIG. 3A is a schematic cross-sectional view for explaining light distribution angle control in the light distribution angle control lens unit 130, and FIG. 3B shows the ratio P / R in the microlens array unit 131. It is a graph which shows the example of control.

According to FIG. 3A, the light (mixed color light) emitted from the LED light source 12 enters the light distribution angle control lens unit 130 via the incident inner surface 130cs, and the light distribution is controlled, so that the light distribution angle. The light exits from the exit surface 130e, which is the exit position of the control lens unit 130. Note that the emitted light is not actually radiated to the outside, but is immediately propagated to the micro lens array portion 131 via the lens array surface 131a. An angular distribution of the emitted light intensity (energy intensity (W / m ² )) is indicated by an intensity distribution 15. The emitted light intensity is a normalized intensity with the maximum value being 1 in FIG.

The light distribution angle θ _d of the emitted light is a generatrix in a cone formed by a generatrix in which the emitted light intensity is 0.5 (half the maximum intensity) with the maximum intensity direction (z′-axis direction) of the emitted light as an axis. Is defined as twice the angle formed by the z ′ axis and the full width at half maximum of the emitted light. The intensity distribution 15 in FIG. 3A is a distribution of outgoing light with a light distribution angle θ _d = 40 °.

Here, light emitted from the exit surface 130e as light distribution angle theta _d becomes large dispersed, whereas, the center illuminance at the light emitted from the exit surface 130e as light distribution angle theta _d becomes smaller the higher. In the present invention, it is preferable that the light distribution angle control lens unit 130 controls the light (mixed color light) emitted from the LED light source 12 to a light distribution angle θ _d having a value in the range of 5 ° to 40 °. . That is,
(1) 5 ° ≦ θ _d ≦ 40 °
It is preferable that

Indeed, then as described with reference to FIG. 3 (B), the place of the simulation experiment by combining the light distribution angle control lens 130 and the microlens array portion 131, light distribution angle theta _d is the above equation ( In the case of taking a value within the range of 1), it has been confirmed that irradiation light having no color unevenness (yellow ring) and maintaining the central illuminance is realized by controlling the ratio P / R. Here, by setting the light distribution angle θ _d to 5 ° or more, the optical dimensional accuracy of the light distribution angle control lens unit 130 required for controlling the light distribution angle θ _d is usually It is within the range that can be realized at the manufacturing cost. In fact, in order to ensure that the light distribution angle is kept within 3 ° to 4 °, processing accuracy is required more than the production process of the normal illumination device optical system, and it is usually more expensive than necessary. I know from my experience.

On the other hand, distribution angle theta _d is the case of 40 ° or less, the dispersion-equalizing effect of the light distribution angle control lens unit 130 is effectively exhibited. Actually, when the light distribution angle θ _d exceeds 40 °, there is almost no contribution of dispersion by the microlens array portion 131 due to an experiment similar to the simulation experiment in FIG. It has been confirmed. For this reason, it has been clarified that an irradiation range in which a necessary central illuminance can be secured according to a predetermined illumination target is realized only when the light distribution angle θ _d is 40 ° or less.

As described above, the light with the light distribution angle θ _d controlled to a value within the range of the above equation (1) is emitted from the light distribution angle control lens unit 130, as will be described below. Therefore, the central illuminance and the degree of dispersion of the irradiation light can be adapted to the illumination target.

  FIG. 3B shows the relationship between the ratio P / R in the microlens array portion 131, the central illuminance of the emitted light, and the full width at half maximum (FWHM) obtained by an optical simulation experiment. Here, the optical simulation experiment was performed using the Monte Carlo method of non-sequential ray tracing. Further, the microlens array portion 131 has a plurality of microlenses 131m in a regular hexagonal array, and each microlens 131m has a shape that becomes a hemispherical lens portion.

The light distribution angle θ _d of the light emitted from the light distribution angle control lens unit 130 is 8.5 °. Further, the central illuminance (unit: lux (lx)) and FWHM (°) are each represented by a standard value where the maximum value in the simulation measurement range is 1. The experimental results described below using the ratio P / R as a parameter are the same even if the actual dimensions (P value and R value) are different from the principle of the optical system if the ratio P / R is the same. It should be noted. The ratio P / R is a value in each of the y′-axis direction and the x ″ -axis direction showing an angle of 60 ° with respect to the y′-axis in FIG. Have the same value.

  According to FIG. 3B, as the ratio P / R increases from zero (the light emitting surface is a surface without unevenness), the pitch P of the microlenses relatively increases, and the convex region of the microlens expands. . As a result, the dispersion effect of the microlens array portion 131 is enhanced and the FWHM of the emitted light is increased, while the central illuminance is monotonously decreased. That is, an effect of suppressing the occurrence of color unevenness such as a yellow ring appears.

  Here, when the inflection point of the FWHM curve is calculated from the second derivative of the FWHM shown in FIG. 3B, the ratio P / R at the inflection point is 0.4. Thus, it is confirmed that when the ratio P / R is 0.4 or more, the FWHM starts to increase substantially and the effect of suppressing the occurrence of color unevenness becomes significant. On the other hand, when the ratio P / R exceeds 1.73, as described with reference to FIGS. 2A1 and 2A2, the microlens 131m is within the lens array surface 131a of the light distribution angle control lens unit 130. No area is formed. That is, a gap is generated between the minute lenses 131m. As a result, the dispersion action by the minute lens 131m is reduced.

  Therefore, the ratio P / R is preferably 0.4 or more and 1.73 or less in this regular hexagonal arrangement. By controlling the ratio P / R in this way, it is possible to obtain irradiation light having a desired central illuminance in which the mixed color light emitted from the LED light source 12 is sufficiently uniformed. Furthermore, even in the square array, the result that the ratio P / R is 0.4 or more and preferably 1.41 or less is obtained by the same optical simulation experiment.

  As described above, these ratio P / R values 1.73 and 1.41 are both small lenses within the lens array surface 131 of the micro lens array section 131 in the y′-axis direction and the x ″ -axis direction. This is an upper limit value for preventing formation of a region that is not 131 m. Accordingly, when considering the above results together, as shown in FIGS. 2A1 and 2B, when the radius of curvature R and / or pitch P is different in the direction of each axis connecting the lens apexes, the lens In the direction of each axis connecting the lens vertices in the array surface 131a, the ratio P / R is 0.4 or more, and an upper limit that does not form a region that is not a microlens in the lens array surface 131a of the microlens array portion 131. It will be appreciated that it is preferably less than or equal to the value.

Even when the light distribution angle θ _d takes other values within the range of the above formula (1) (5 ° ≦ θ _d ≦ 40 °), the same result as described above is obtained by the optical simulation. Obtained. That is, irradiation light having FWHM as designed without color unevenness (yellow ring) was realized under the condition of 5 ° ≦ θ _d ≦ 40 ° in the above-mentioned preferable range of the ratio P / R.

[Example 1: Rectangular array of microlenses]

An irradiation experiment using the microlens array unit 131 including a plurality of microlenses 131m arranged in a rectangular shape was performed by optical simulation. Table 1 shows the experimental results of Example 1.

In Example 1 of Table 1, the light distribution angle θ _d of the light distribution angle control lens unit 130 is 9 °, and the lens diameter d _d (FIG. 1C) of the light distribution angle control lens unit 130 is 23 mm. (Mm). Overall shape microlens array portion 131 (the lens array surface 131a), in x'y 'plane, a circular shape having a large area enough than circle the lens diameter d _d forms. As shown in FIG. 2B, the curvature radii R _{x ′} and R _{y ′} are the curvature radii in the cross section taken along the z′x ′ plane and the cross section taken along the y′z ′ plane of the microlens 131m. The curvature radii R _{x ′} and R _{y ′} are 1.0 mm, and the shape of each microlens is a hemispherical portion. Also, the pitches P _{x ′} and P _{y ′} are the distances between the apexes of the minute lenses 131m adjacent in the x′-axis direction and the y′-axis direction, respectively, as shown in FIG. 2B. Further, F _{x ′} and F _{y ′} are angles formed by buses existing in a cross section by the z′x ′ plane and the y′z ′ plane including the apex, respectively, in the cone formed by the full width at half maximum of the emitted light. .

  In Table 1, the central luminous intensity is the optical axis passing through the centers of the light distribution angle control lens unit 130 and the microlens array unit 131 (in the z′-axis direction) (the dashed line in FIG. 1B). It is the luminous intensity (unit: candela (cd)) of the emitted light at the intersection with the light emitting surface of the array part 131. Further, the half-value illuminance is the illuminance (unit is lux (lx)) that is half the value of the central illuminance in an illumination target (planar shape perpendicular to the optical axis) 1 m away from the LED illumination device in the optical axis direction. is there.

According to Table 1 and FIG. 4A, in Example 1, the microlenses 131m are arranged in a rectangular shape. The radii of curvature R _{x ′} and R _{y ′} are both equal to 1.0 mm. The pitches P _{x ′} and P _{y ′} between the microlenses are 0.8 mm and 1.2 mm, respectively, and the pitch P has anisotropy. That is, the pitch P is different between the directions of the x ′ axis and the y ′ axis which are a plurality of axes connecting the lens apexes and perpendicular to each other. As a result, the ratio P / R also has anisotropy (P _{x ′} / R _{x ′} = 0.8, P _{y ′} / R _{y ′} = 1.2). The central luminous intensity is 205 cd, and the luminous intensity distributions are different Gaussian distributions in the x′-axis direction and the y′-axis direction.

Furthermore, in Example 1, the full widths at half maximum F _{x ′} and F _{y ′} are 24.5 ° and 33.5 °, respectively, which are different values. In addition, the point where 110 lx is measured as the half-value illuminance is ± 40 cm from the origin on the x ′ axis when the x′y′z ′ coordinate system (the intersection with the optical axis is the origin) is introduced into the illumination target plane. Centimeter), and a position of ± 60 cm from the origin on the y ′ axis.

  FIG. 4A is a graph showing the illuminance distribution in the x′y ′ plane in the first embodiment.

  As shown in FIG. 4A, in Example 1 in which the dispersion of irradiation light has anisotropy in the x′-axis direction and the y′-axis direction, the illumination shape when the emitted light irradiates the illumination target plane is It becomes a substantially rectangular shape. Note that the illuminance distribution in FIG. 4A is a planar distribution at a position 1 m along the optical axis from the microlens array portion 131 (perpendicular to the optical axis).

  Therefore, it is understood that the illumination shape can be controlled to a rectangular shape by arranging the microlenses 131m in a rectangular shape and giving anisotropy to the ratio P / R (pitch P). Further, in this simulation experiment, no distribution corresponding to the blue and yellow rings in the central portion is seen in the illumination shape, and it has been confirmed that the uniformization of the irradiation light is promoted.

[Example 2: Hexagonal arrangement of microlenses]

An irradiation experiment using a microlens array portion 131 having a plurality of microlenses 131m arranged in a hexagonal shape was performed by optical simulation. Table 2 shows the experimental results of Example 2.

In Example 2 of Table 2, the light distribution angle θ _d of the light distribution angle control lens unit 130 is 9 °, and the lens diameter d _d (FIG. 1C) of the light distribution angle control lens unit 130 is 23 mm. It is. The shape of the micro lens array 131 (lens array surface 131a), in x'y 'plane, a circular shape having a large area enough than circle the lens diameter d _d forms. As shown in FIG. 2A, the curvature radii R _{x ′} and R _{y ′} are the curvature radii in the cross section taken along the z′x ′ plane and the cross section taken along the y′z ′ plane of the microlens 131m. These radii of curvature R _{x ′} and R _{y ′} are 2.0 mm and 1.0 mm, respectively, and the shape of each microlens is an elliptical spherical portion. Further, as shown in FIG. 2A, the pitches P _{x ′} and P _{y ′} are the distances between the vertexes of the minute lenses 131m adjacent in the x ″ axis direction and the y ′ axis direction, respectively. Here, the x ″ axis is an axis in a direction rotated by 60 ° from the y ′ axis toward the x ′ axis in the x′y ′ plane. Further, F _{x ′} and F _{y ′} are angles formed by buses existing in a cross section by the z′x ′ plane and the y′z ′ plane including the apex, respectively, in the cone formed by the full width at half maximum of the emitted light. .

According to Table 2, in Example 2, the microlenses 131m are arranged in a hexagonal shape, the radii of curvature _{Rx ′} and _{Ry ′} are 2.0 mm and 1.0 mm, respectively, and the radii of curvature R are different. Has a direction. That is, the radius of curvature R differs between the direction of the y ′ axis and the direction of the x ′ axis perpendicular to the y ′ axis. On the other hand, the pitches P _{x ′} and P _{y ′} between the micro lenses are both equal to 0.8 mm. As a result, the ratio P / R has anisotropy (P _{x ′} / R _{x ′} = 0.4, P _{y ′} / R _{y ′} = 0.8). The central luminous intensity is 580 cd, and the luminous intensity distributions are different Gaussian distributions in the x′-axis direction and the y′-axis direction.

Furthermore, in Example 2, the full widths at half maximum F _{x ′} and F _{y ′} are 12.5 ° and 21.5 °, respectively, which are different values. In addition, the point where 700 lx is measured as the half-value illuminance is ± 20 cm from the origin on the x ′ axis when the x′y′z ′ coordinate system (the intersection with the optical axis is the origin) is introduced into the illumination target plane. The position is ± 38 cm from the origin on the y ′ axis.

  FIG. 4B is a graph showing the illuminance distribution in the x′y ′ plane in the second embodiment.

  As shown in FIG. 4 (B), in Example 2 in which the dispersion of the irradiation light has anisotropy in the x′-axis direction and the y′-axis direction, the illumination shape when the emitted light irradiates the illumination target plane is It becomes a substantially elliptical shape. Note that the illuminance distribution in FIG. 4B is a distribution in a planar shape (perpendicular to the optical axis) located at a position 1 m along the optical axis from the microlens array portion 131.

  Therefore, it is understood that the illumination shape can be controlled to an elliptical shape by arranging the micro lenses 131m in a hexagonal shape and giving anisotropy to the ratio P / R (curvature radius R). Further, in this simulation experiment, no distribution corresponding to the blue and yellow rings in the central portion is seen in the illumination shape, and it has been confirmed that the uniformization of the irradiation light is promoted.

[Example 3: Rectangular arrangement of microlenses, ratio P / R isotropic]

An irradiation experiment using the microlens array unit 131 including a plurality of microlenses 131m arranged in a rectangular shape was performed by optical simulation. Table 3 shows the experimental results of Example 3.

In any of Examples 3-1, 3-2, and 3-3 in Table 3, the light distribution angle θ _d of the light distribution angle control lens unit 130 is 9 °, and the lens of the light distribution angle control lens unit 130 The diameter d _d (FIG. 1C) is 23 mm. The shape of the micro lens array 131 (lens array surface 131a), in x'y 'plane, a circular shape having a large area enough than circle the lens diameter d _d forms. The radii of curvature R _{x ′} and R _{y ′} are different from each other, and the shape of each microlens is an elliptical spherical portion.

According to Table 3, in Example 3-1 and 3-2, the microlenses 131m are arranged in a rectangular shape, and the radii of curvature R _{x ′} and R _{y ′} are 1.0 mm and 1 respectively in Example 3-1. 0.05 mm, and 1.0 mm and 0.95 mm in Example 3-2, respectively, and the curvature radius R has anisotropy. The pitches P _{x ′} and P _{y ′} between the microlenses are also 0.8 mm and 0.84 mm in Example 3-1, respectively, and are 1.2 mm and 1.14 mm in Example 3-2, respectively. The pitch P also has anisotropy. That is, both the radius of curvature R and the pitch P are between a direction of the x′-axis for the radius of curvature R and a direction of the y′-axis perpendicular to the x′-axis. (X ′ axis and y ′ axis) are different between the respective directions. In Examples 3-1 and 3-2, this makes the ratio P / R isotropic. That is, in Example 3-1, _{Px '} / _Rx' = _{Py '} / _Ry' = 0.8, and in Example 3-2, _{Px '} / _Rx' = _{Py '} / _Ry'. = 1.2.

The central luminous intensity is 290 cd in Example 3-1, 150 cd in Example 3-2, and the luminous intensity distribution is a Gaussian distribution that matches in the x′-axis direction and the y′-axis direction. Furthermore, in Examples 3-1 and 3-2, the full widths at half maximum F _{x ′} and F _{y ′} are both 24.5 ° in Example 3-1 and 34.5 ° in Example 3-2. And the same value.

According to Table 3, also in Example 3-3, the micro lenses 131m are arranged in a rectangular shape, the curvature radii R _{x ′} and R _{y ′} are 1.0 mm and 2.0 mm, respectively, and the curvature radius R is Has anisotropy. Further, the pitches P _{x ′} and P _{y ′} between the microlenses are 0.4 mm and 0.8 mm, respectively, and the pitch P has anisotropy. That is, both the radius of curvature R and the pitch P are between a direction of the x′-axis for the radius of curvature R and a direction of the y′-axis perpendicular to the x′-axis. (X ′ axis and y ′ axis) are different between the respective directions. Also in Example 3-3, this makes the ratio P / R isotropic (P _{x ′} / R _{x ′} = P _{y ′} / R _{y ′} = 0.4). The central luminous intensity is 875 cd, and the luminous intensity distribution is a Gaussian distribution that matches in the x′-axis direction and the y′-axis direction.

Further, in Example 3-3, the full widths at half maximum F _{x ′} and F _{y ′} are both 12 ° and the same value. In addition, the point where 1050 lx ′ is measured as the half-value illuminance is ± 22 cm from the origin on the x ′ axis when the x′y′z ′ coordinate system (the intersection with the optical axis is the origin) is introduced into the illumination target plane. The position is ± 22 cm from the origin even on the y ′ axis. That is, the illuminance distribution is also isotropic in the x′-axis direction and the y′-axis direction.

  FIG. 4C is a graph showing the illuminance distribution in the x′y ′ plane in Example 3-3.

As shown in FIG. 4C, the ratio P / R is isotropic in the x′-axis direction and the y′-axis direction (P _{x ′} / R _x) even though the microlens array is a rectangular array. _In Example 3-3 where _' = _Py' / _{Ry '} ), the illumination shape when the emitted light irradiates the illumination target plane is a substantially square shape. Note that the illuminance distribution of FIG. 4C is a planar distribution at a position 1 m along the optical axis from the microlens array portion 131 (perpendicular to the optical axis). Moreover, as shown in Table 3, also in Examples 3-1 and 3-2, a substantially square illuminance distribution similar to that in FIG. 4C is obtained.

  From the results of Examples 3-1, 3-2, and 3-3 described above, the illumination shape can be made square by making the ratio P / R isotropic even if the microlenses 131m are arranged in a rectangular shape. It is understood that it can be controlled. Further, in this simulation experiment, no distribution corresponding to the blue and yellow rings in the central portion is seen in the illumination shape, and it has been confirmed that the uniformization of the irradiation light is promoted.

In addition, the degree of anisotropy in the radius of curvature R and the pitch P in Example 3-1 is as follows.
_{(R y '-R x')} / R x '(= (P y' -P x ') / P x') = + 0.05 (+ 5%)
The degree of anisotropy in the curvature radius R and pitch P in Example 3-2 is
_{(R y '-R x')} / R x '(= (P y' -P x ') / P x') = - 0.05 (-5%)
It is. If the microlens array unit 131 has at least ± 5% anisotropy under the optical system processing accuracy at the manufacturing site, the curvature radius R and the pitch P are adjusted as described above to change the illumination shape. Experiments have confirmed that it can be set to a substantially square shape.

  As described above in detail with reference to various embodiments, according to the LED illumination device 10 of the present invention, the uniformizing optical body 13 promotes the color mixing and color uniformity of the irradiation light, and the LED light source 12 It is possible to suppress the occurrence of color unevenness such as a yellow ring. In addition, by controlling the optical configuration (microlens arrangement, radius of curvature R and pitch P) of the uniformizing optical body 13 with respect to each of different directions, for example, from an illumination state that illuminates a wide range like a conventional fluorescent lamp, It is possible to realize a highly condensing illumination state such as a spotlight while suppressing occurrence of color unevenness.

  Moreover, according to the LED lighting device 10 of the present invention, it is possible to achieve a necessary illuminance according to the illumination target and an illumination shape suitable for the shape of the illumination target while suppressing occurrence of color unevenness. As a result, it is possible to greatly reduce the emitted light that is out of the illumination target and is wasted, and the illumination target can be illuminated with sufficient illuminance under the inherent low power consumption of the LED illumination. As a result, more efficient lighting can be realized.

Here, the range of “substantially” in a substantially rectangular shape or a substantially square shape will be described. First, the illumination region is a region in which light within the light distribution angle (full width at half maximum) range of the emitted light illuminates the illumination target surface (perpendicular to the normal of the emission surface) immediately below the LED illumination device 10. Suppose there is. The illumination shape is assumed to be the shape of this illumination area. When a minimum rectangle or square circumscribing the illumination shape is assumed, a ratio r (≦ 1) between the area S of the illumination region (illumination shape) and the area S ₀ of the circumscribed rectangle or square is
(2) r = S / S ₀ ≧ 0.9
When the above condition is satisfied, the illumination shape of the illumination area is assumed to be “substantially” rectangular or “substantially” square.

Here, the lower limit value of r = 0.9 is the value of the area ratio S / S ₀ in Example 3-1, and the degree of anisotropy at the curvature radius R and the pitch P is 5% as described above. This is the value in some cases. Under the optical system processing accuracy at the manufacturing site, if the anisotropy setting is at least 5%, the effect on the anisotropic illumination shape is ensured. It is a boundary. Moreover, the illumination shape in Example 1 (Table 1, FIG. 4 (A), Example 2 (Table 2, FIG. 4 (B)), and Example 3 (Table 3, FIG. 4 (C)) mentioned above is also, It has been confirmed that the condition of the above formula (2) is satisfied.

The ratio of the area S ′ of the ellipse to the area S ₀ ′ of the rectangle circumscribing the ellipse is about 0.79. The above-mentioned value of r = 0.9 is approximately the median (intermediate value) between about 0.79 and 1. Furthermore, the range of “substantially” in the substantially elliptical shape is similarly defined using the maximum elliptical area that is inscribed respectively.

[LED lighting device 1]

  FIG. 5 is a front view, a cross-sectional view, and a rear view showing an embodiment of an LED lighting device according to the present invention. Here, FIG. 5B shows a cross section taken along the plane AA of FIG.

  According to FIGS. 5A and 5B, the LED lighting device 1 includes a case 16, a plurality of LED lighting devices 10 arranged in series in the case 16, and an opening provided in the upper part of the case 16. A lid 17 is provided so as to be fitted, and a power line 18 for supplying power to each LED lighting device 10.

  The case 16 is made of a metal material such as aluminum die cast or stainless steel, or a non-permeable plastic material containing polycarbonate, PET, acrylic, or the like, and is opaque. Case 16 may be formed by sheet metal processing. The lid 17 is formed of a transparent material such as a glass material such as tempered glass, or a transparent plastic material including polycarbonate, PET, acrylic, or the like. Further, the plurality of LED lighting devices 10 are installed with the micro lens array part 131 facing the lid body 17. Thereby, the emitted light from the plurality of LED lighting devices 10 is radiated through the lid body 17 and becomes irradiation light.

  The bases 11 of the plurality of LED lighting devices 10 are arranged in contact with each other or linearly with a predetermined interval. As a modification mode, the plurality of bases 11 are integrated into one circuit board, and a plurality of LED light sources 12 and a plurality of uniformizing optical bodies 13 are installed on the circuit board to form a plurality of LED lighting devices 10. It is good.

  Any of the various embodiments (Examples 1 to 3) described above can be adopted as the homogenizing optical body 13 of the LED lighting device 10, particularly the microlens array portion 131. Further, the radius of curvature R, the pitch P, or both of them is between the direction of one axis in the lens arrangement plane for the radius of curvature R and the direction of the axis perpendicular to this axis, and the lens arrangement plane for the pitch P. If the microlens array portion 131 is different between the directions of the axes connecting the lens vertices, it can be adopted. As a result, it is possible to emit the emitted light whose uniformity is further promoted and whose illuminance and illumination shape are controlled.

  As shown in FIG. 5C, the power supply line 18 is drawn out from the base 11 to the outside through, for example, a slit opening 160 provided at the bottom end of the case 16. Between the power line 18 and the cut opening 160 and between the lid 17 and the opening of the case 16, a waterproof / oil-proof treatment using an adhesive, a seal member, or the like is performed according to the use environment. It is also preferred that

[Lighting shape of LED lighting device]

  FIG. 6 is a perspective view schematically showing two embodiments according to the illumination shape of the LED illumination device according to the present invention.

  According to the embodiment of FIG. 6A, the LED illumination device 1 illuminates the illumination target plane. In this LED illumination device 1, a plurality of LED illumination devices 10 are arranged, and the illumination target plane is a plane perpendicular to the optical axis of these LED illumination devices 10 (homogenizing optical bodies 13).

The LED lighting device 10 employs, for example, the same form as that of the first embodiment or the third embodiment described above, and the illumination area 200 formed by the emitted light 20 of each LED lighting device 10 on the illumination target plane is constant. Including an illumination area portion having a width W of ₃₀₀ , and is set to have a substantially rectangular shape or a substantially square shape.

In this case as well, the range of “substantially” in the substantially rectangular shape or the substantially square shape is a range that satisfies the condition of the above-described formula (2) r = S / S ₀ ≧ 0.9. Further, the “constant” range in the constant width is a range in which the variation of the width (W ₃₀₀ ) in the illumination region portion is within ± 5%. It has been confirmed that the substantially rectangular shape or the substantially square shape includes an illumination region in which the fluctuation width of the width W ₃₀₀ is within ± 5%.

  In this case, the irradiation light 30 emitted from the LED lighting device 1 is arranged such that the emitted light 20 is partially overlapped with each other. As a result, the illumination area 300 formed by the irradiation light 30 on the illumination target plane is arranged such that the illumination areas 200 partially overlap each other, and is in the apparatus longitudinal direction (array direction of the LED illumination device 10: x-axis direction). It becomes the extended substantially rectangular shape.

  According to the embodiment of FIG. 6B, the LED lighting device 10 in the lighting device adopts, for example, the same form as in the above-described embodiment 2, and the emitted light 21 of each LED lighting device 10 is The illumination area 210 formed on the illumination target plane is set to be substantially elliptical.

In this case, the irradiation light 31 radiated from the LED lighting device 1 is arranged such that the emitted light 21 is partially overlapped with each other. As a result, the illumination area 310 formed by the irradiation light 31 on the illumination target plane is arranged such that the illumination areas 210 partially overlap each other, and has an illumination area portion having a certain width W ₃₁₀ , and the longitudinal direction of the apparatus. It becomes a rectangular shape in which both sides in the direction (x-axis direction) are curved.

  According to the embodiment described above, it is possible to obtain irradiation light whose uniformity is promoted and whose illumination shape is controlled from the LED illumination device. Here, by matching the illumination shape of the irradiation light to the shape of the irradiation target, it is possible to illuminate only the lighting target. As a result, the required illuminance can be ensured with high power efficiency within the required range.

[Workbench lighting]

  FIG. 7 is a perspective view schematically showing an embodiment of the illumination method by the LED illumination device of the present invention.

  According to FIG. 7, the LED lighting device 1 is installed on a work table 3 having a work area 3 s that is a surface to be irradiated. The work area 3s has a square shape. Here, since the work implement is installed immediately above the work area 3s, the LED lighting device 1 is installed at a position obliquely above the work area 3s to illuminate the work area 3s.

The irradiation light 33 radiated from the LED lighting device 1 has an illumination region with a certain width W _{33 on} a surface 330 perpendicular to the optical axis (of the LED lighting device 10), and has a substantially rectangular shape. However, since the irradiation light 33 is obliquely incident on the work area 3s, the illumination area 331 in the work area 3s by the illumination light 33 is substantially square. Here, the irradiation light 33 can illuminate only the work area 3 s by making the substantially square shape of the irradiation light 33 substantially coincide with the square shape of the work area 3 s.

  Here, as a modification, it is also possible to realize a substantially rectangular illumination region 331 having a different long / short side ratio by using the irradiation light 33 having a substantially rectangular shape or a substantially square shape on the surface 330. Alternatively, a substantially elliptical illumination region 331 having a substantially circular shape or a different major / short axis ratio can be realized by using the substantially elliptical irradiation light 33 on the surface 330.

The ratio of the orthogonal sides or the ratio of the orthogonal axes in the illumination shape of the illumination area 331 adjusts the angle θ ₄₀ formed by the optical axis of the irradiation light 33 from the LED illumination device 1 and the normal line of the work area 3s. Thus, it can be arbitrarily set within a considerable range. As described above, also in the present embodiment, it is possible to realize illumination that is free of waste and in which color unevenness is suppressed, in which illuminance required according to the illumination target is ensured.

[Lighting of roads, passages or roads by LED lighting device 1]

  FIG. 8 is a schematic view for explaining another embodiment in the illumination method by the LED illumination device of the present invention. In each figure, an XYZ coordinate system serving as an indicator of the direction of illumination is shown.

  FIG. 8A shows an embodiment in which the road (or passage) 5 is illuminated using the LED lighting device 1. Here, the LED illumination device 10 of the LED illumination device 1 adopts, for example, the same form as in the first or third embodiment, and the illumination region 340 of the LED illumination device 1 has an illumination region portion having a certain width. And has a substantially rectangular shape (or a substantially square shape).

According to FIG. 8 (A), LED illumination device 1 is installed at a predetermined distance D ₁ above the at least one end portion in the width direction of the road 5 (X-axis direction). Here, the irradiation light 34 radiated from the LED lighting device 1 irradiates the road surface 50 that is the irradiation target surface, and forms a substantially rectangular illumination region 340 on the road surface 50.

  The illumination areas 340 formed by the plurality of LED illumination devices 1 are arranged in the longitudinal direction (Y-axis direction) of the road 5 while forming an overlapping area 340v by partially overlapping each other. As a result, the illumination shape of the entire illumination area of the road surface 50 is a shape arranged in the longitudinal direction (Y-axis direction) of the road 5 while the substantially rectangular shapes by the irradiation light 34 partially overlap each other.

Further, the LED lighting device 1 is installed so as to have a tip portion with respect to the road surface 50. Thereby, the exit surface of the LED lighting device 10 in the apparatus 1 forms an angle θ _el with respect to the road surface 50 in a cross section (ZX plane) orthogonal to the longitudinal axis (Y axis) of the road surface 50. As a result, the optical axis of the irradiation light 34 is inclined by the angle θ _{el with} respect to the normal line of the road surface 50 in the ZX plane.

  The exit surface of the LED illumination device 10 is the upper surface of the microlens array portion 131 (the surface including each vertex of the microlens) and is a surface parallel to the lens array surface 131a. Further, the optical axis of the irradiation light 34 is an axis in the optical axis direction of the emitted light from the LED lighting device 10 in the LED lighting device 1, and is a region of the entire emitting surface of the LED lighting device 10 arranged in the device 1. Is defined as the axis through the center of

In this way, by tilting the optical axis of the irradiation light 34 with respect to the normal line of the road surface 50, the width W ₃₄₀ of the illumination region 340 in the X-axis direction is changed, and as shown in FIG. W ₃₄₀ can be substantially matched with the width W ₅₀ of the road surface 50 in the X-axis direction. Thereby, in the width direction (X-axis direction) of the illumination region 340, the necessary minimum illuminance (for example, 3lx) required for the illumination of the road 5 can be ensured. The above “substantially match” is based on the premise that the width W ₃₄₀ of the illumination area 340 and the illuminance range width equal to or greater than the required minimum illuminance generally match each other. Actually, for example, even if the width W ₃₄₀ of the illumination area 340 is slightly smaller than the width W _{50 of the} road surface 50, the required minimum illuminance may be satisfied, and vice versa, “Mostly match” is intended to include these ranges as well.

On the other hand, in the LED lighting device using the conventional convex lens, the irradiation shape is a circular shape or an elliptical shape close to a circular shape. As a result, as shown in FIG. 8 (C), when you try to provide illumination required on the road surface 50, since the diameter of the illumination shape larger inevitably than the width W ₅₀ of the road surface 50, the illumination light Unnecessary portions outside the road surface 50 are also illuminated considerably. As a result, the power for illumination is wasted. Moreover, this situation cannot be solved even if this LED lighting device is inclined and installed in the ZX plane.

  On the other hand, in the illumination using the LED illumination device 1 according to the present invention, the illumination shape can be made approximately coincident with the road surface 50 as shown in FIG. Therefore, it is possible to sufficiently suppress the illumination light 34 from illuminating unnecessary portions outside the road surface 50.

  Furthermore, the end portion in the longitudinal direction (Y-axis direction) of the road surface 50 having the lowest illuminance in the illumination region 340 overlaps with the end portion of the adjacent illumination region 340 to form an overlap region 340v. As a result, even if there is an area where the required minimum illuminance (for example, 3lx in the case of a security light) is not ensured in the illumination area 340 alone, adjustment is performed so that the necessary minimum illuminance can be ensured in the overlapping area 340v. This makes it possible to secure the necessary illuminance on the entire road surface 50.

  Further, when the necessary minimum illuminance is ensured by providing the overlapping region 340v, the value of the maximum illuminance in the illumination region 340 can be suppressed without being unnecessarily increased. This makes it possible to reduce the height difference of the illuminance in the entire illumination area and to reduce the power consumption required to ensure the necessary minimum illuminance.

  When the required minimum illuminance is ensured by the illumination area 340 alone, adjacent illumination areas may be arranged adjacent to each other as in the illumination area 340 ′ of FIG. 8B. In this case, since the overlapping region 340v is not provided, the number of LED lighting devices 1 required per unit length of the road 50 can be reduced if the size and shape of the illumination region are not changed.

  In any case, in the microlens array unit 131 in the LED lighting device 1, the curvature radius R and pitch P of the plurality of microlenses 131m, or both the curvature radius R and pitch P are determined in the lens array surface 131a. Different values are set and controlled between directions. As a result, the light distribution angle (or FWHM) in the ZX plane and the light distribution angle (or FWHM) in the YZ plane of the emitted light of the LED lighting device 10, that is, the irradiation light of the LED lighting device 1, are independent. Each can be controlled individually. Therefore, the range of the illumination region 340 in the width direction (X-axis direction) of the road (or passage) 5 and the range of the illumination region 340 in the longitudinal direction (Y-axis direction) of the road (or passage) 5 are individually set. Control becomes possible. Thereby, the illumination area (illumination shape) suitable for the road surface 50 can be realized in both the width direction and the longitudinal direction of the road surface 50.

  As described above, by using the LED lighting device 1, it is possible to realize illumination without waste, in which illuminance required according to the road surface 50 is ensured.

  FIG. 9 is a schematic diagram for explaining the embodiment shown in FIG. 8 in which the optical axis of the irradiation light 34 is inclined with respect to the normal line of the road surface 50, and a state in which the LED lighting device 1 is installed in the road. FIG.

FIG. 9A is a schematic diagram showing a relationship between the LED lighting device 1 installed so as to have a tip portion with respect to the road surface 50 and the road 5. According to the figure, the LED lighting device 1 is inclined at an angle θ _el with respect to the road surface 50 in the ZX plane at the tip of an L-shaped pole standing on the side of the road (or passage) 5. It is attached as follows. As a result, the optical axis of the irradiation light 34 is inclined at an angle theta _el with respect to the normal to the road surface 50 in the ZX plane. In addition, as shown with the broken line of FIG. 9 (A), it is also possible to install the LED illuminating device 1 in parallel with the road surface 50 directly above the center of the road surface 50 in the width direction (X-axis direction). . In this case, the optical axis of the irradiation light 34 is also parallel to the normal line of the road surface 50.

  FIG. 9B shows a state in which the LED lighting device 1 is installed in the path 6. The road 6 has a cable (/ tube) shelf 61 for accommodating a communication cable, a power transmission cable, a gas pipe, and the like, and is a tunnel passage that is large enough for a person to enter for work.

  According to FIG. 9B, the LED lighting device 1 is installed in the center of the ceiling portion of the road 6, and the illumination area 350 of the irradiation light 35 includes a floor surface 60 and at least a side surface 60 s including the position of the cable shelf 61. The lower part of That is, the illumination area 350 is set so as to illuminate the cable (• pipe) of the cable shelf 61 that is the work target.

  Here, if the illumination shape of the illumination region 350 is substantially rectangular, the upper end (boundary) of the illumination region 350 on the side surface 60s is more than the cable shelf 61 extending along the longitudinal direction (Y-axis direction) of the path 6. It is on the upper side and becomes a straight line extending in parallel with the cable shelf 61. As a result, the cable shelf 61 can be illuminated all along the longitudinal direction (Y-axis direction) without waste.

  As a change mode, as shown by the broken line in FIG. 9B, the LED illumination device 1 is installed obliquely upward as viewed from the center of the floor surface 60, and the optical axis of the irradiation light 35 is changed to that of the floor surface 60. It is also possible to tilt with respect to the normal.

  Here, as a condition for illumination of the way 6, the necessary minimum illuminance is, for example, 5 lx, the average illuminance in the illumination area is, for example, 15 lx or more, and the interval between the illumination devices is, for example, 10 m. It is known from simulation experiments that it is possible to implement illumination satisfying this condition by performing the illumination described above using the LED illumination device 1.

  In addition, it is also preferable to install in the ceiling part of the road 6 without hanging down the LED lighting apparatus 1 in the road 6. As a result, it becomes easy to take a sufficient height of the lighting device and widen the illumination area in the road 6 with a limited height. Furthermore, it becomes easy to avoid the situation where the irradiation light from the lighting device directly enters the eyes of the worker and hinders the work. Moreover, it is also preferable that the LED lighting device 1 installed on the road 6 is provided with a secondary battery for guaranteeing illumination for, for example, 30 minutes as an evacuation time at the time of a power failure.

10A shows the setting of the angle θ _{el and} the setting of the position of the LED lighting device 1 for making the width W ₃₄₀ of the illumination area 340 coincide with the width W _{50 of the} road surface 50 shown in FIG. 9A. It is the schematic for demonstrating. Here, for the sake of brevity, the irradiation light 34 approximates that emitted from one point of the LED lighting device 1. In addition, the following description is the content applicable also to the illumination by LED illuminating device 7, 8, 9 and 9 'demonstrated later.

As shown in FIG. 10A, it is assumed that the width W ₃₄₀ of the illumination region 340 matches the width W _{50 of the} road surface 50. Further, the irradiation angle of the irradiation light 34 from the LED lighting device 1 is α, and the height from the road surface 50 of the LED lighting device 1 (the point light source position) is h ₁ . Note that the irradiation angle is an angular range in which light rays constituting the irradiation light forming the illumination area spread.

In this case, the angle θ _el is expressed by the following equation (3) W ₅₀ = h ₁ · tan (α / 2 + θ _el ) + h ₁ · tan (α / 2−θ _el )
Meet. Accordingly, by solving the equation (3), the angle θ _el under the condition of W ₃₄₀ = W ₅₀ can be obtained.

Further, by using the angle θ _el obtained by solving the above equation (3), the position l _{1 in} the width direction (X-axis direction) from the end of the road surface 50 of the LED lighting device 1 (the point light source position thereof) is The following equation (4) l ₁ = h ₁ tan (α / 2−θ _el )
Is obtained by calculating

FIG. 10B is a schematic diagram for explaining the setting of the irradiation angle β of the irradiation light for arranging the illumination regions 360 by the irradiation light 36 adjacent to each other or partially overlapping with each other in the longitudinal direction. Here, for the sake of brevity, the irradiation light 36 is approximated to that emitted from one point of the LED lighting device 1, and the angle θ _el = 0 °.

As shown in FIG. 10B, the irradiation angle in the YZ plane of the irradiation light 36 from the LED lighting device 1 is β, and the height from the road surface 50 of the LED lighting device 1 (the point light source position) is h _1. And In this case, the condition for causing the illumination areas 360 to be adjacent to each other or partially overlap each other is as follows: (5) β ≧ 2 · tan ⁻¹ (D ₁ / (2h ₁ ))
It is represented by That is, by adopting the LED illumination device 1 having the irradiation angle β satisfying the expression (5), it is possible to illuminate the entire road surface 50 without any problem.

  In any case, in the microlens array unit 131 in the LED lighting device 1, the curvature radius R and pitch P of the plurality of microlenses 131m, or both the curvature radius R and pitch P are determined in the lens array surface 131a. Different values are set and controlled between directions. As a result, the light distribution angle (or FWHM) in the ZX plane and the light distribution angle (or FWHM) in the YZ plane of the emitted light of the LED lighting device 10, and further the irradiation light of the LED lighting device 1 The irradiation angle in the ZX plane and the irradiation angle in the YZ plane can be independently controlled. Therefore, the range of the illumination region 360 in the width direction (X-axis direction) of the road (or passage) 5 and the range of the illumination region 360 in the longitudinal direction (Y-axis direction) of the road (or passage) 5 are individually determined. Control becomes possible. Thereby, the illumination area (illumination shape) suitable for the road surface 50 can be realized in both the width direction and the longitudinal direction of the road surface 50.

[LED lighting device 7]

  FIG. 11 is a front view, a sectional view, and a side view showing another embodiment of the LED lighting device according to the present invention. Here, FIG. 11B shows a cross section taken along plane B-B in FIG.

  11A to 11C, the LED lighting device 7 includes a housing 71, a plurality of LED lighting devices 10 arranged in two rows on the installation surface of the housing 71, and these LED lighting devices. 10, a cover 72 attached to the upper portion of the housing 71 using attachment screws 74 and a power line 73 for supplying power to each LED lighting device 10 are provided.

The casing 71 has a first installation surface 710 and a second installation surface 711 that extend in the longitudinal direction (x-axis direction) of the device 7 and are inclined so as to form an angle θ ₇₁ with each other. Among them, the plurality of LED lighting devices 10 installed in a row on the first installation surface 710 form the first group 10f, and the plurality of LED lighting devices 10 installed in a row on the second installation surface 711 are included. The second group 10s is formed. Accordingly, the LED lighting device 10 belonging to the first group 10f, and the LED lighting device 10 belonging to the second group 10s, the exit surface of each other are arranged at an angle theta _71.

These optical axis _{X 10f} of the first group 10f and the optical axis _{X 10s} of the second group 10s, in the yz plane, the angle _{(6) θ 7x = π-} θ 71 ( in radians)
They are leaning from each other. In the present embodiment, θ ₇₁ is less than π (180 °) (thus θ _7x > 0).

  The optical axis of the first group 10f (second group 10s) is an axis in the optical axis direction of the emitted light from each LED lighting device 10 belonging to the first group 10f (second group 10s), and is the first axis. It is defined as an axis that passes through the center of the entire region of the emission surface of the LED lighting devices 10 belonging to the group 10f (second group 10s).

Here, as described in detail later, the angle θ _7x formed by the optical axis is such that the illumination shape by the irradiation light from the first group 10f and the illumination shape by the irradiation light from the second group 10s are adjacent to each other or partially overlapped. The illumination shape by the irradiation light from the device 7 is formed by aligning them while being arranged.

  The casing 71 is made of a metal material such as aluminum die-casting or stainless steel, or a non-permeable plastic material including polycarbonate, PET, acrylic, or the like, and is opaque. The casing 71 may be formed by sheet metal processing. The cover 72 is made of a transparent material such as a glass material such as tempered glass, or a transparent plastic material including polycarbonate, PET, acrylic, or the like.

  Further, in each of the first group 10f and the second group 10s, the bases 11 of the plurality of LED lighting devices 10 are in contact with each other or arranged linearly at a predetermined interval. As a modification, the plurality of bases 11 are integrated into one circuit board, and a plurality of LED light sources 12 and a plurality of uniformizing optical bodies 13 are installed on the circuit board, and the first group 10f and It is good also as the some LED lighting device 10 which comprises each of 2nd group 10s.

Furthermore, as another embodiment, a plurality of LED lighting devices 10 in the first group 10f and a plurality of LED lighting devices 10 in the second group 10s are alternately arranged or mixed to form one row. It may be done. When arranged alternately, the optical axis X _10f and the optical axis X _10s are switched for each LED lighting device 10 in a row. As still another embodiment, the plurality of LED lighting devices 10 of the first group 10f and the plurality of LED lighting devices 10 of the second group 10s are connected in the front and back of each other to form one row. Also good.

  Any of the various embodiments (Examples 1 to 3) described above can be used for the homogenizing optical body 13 of the LED lighting device 10, particularly the microlens array unit 131, and the homogenization is promoted. Furthermore, it is possible to emit outgoing light with controlled illuminance and illumination shape.

[LED lighting device 8]

  FIG. 12 is a front view and a sectional view showing still another embodiment of the LED lighting device according to the present invention. Here, FIG. 12B shows a cross section taken along the CC plane of FIG.

  According to FIGS. 12A and 12B, the LED lighting device 8 includes a housing 81 and four LED lighting device bodies 100, 101, 102 arranged in parallel on the installation surface of the housing 81. And 103, a cover 82 attached to the upper part of the housing 81 using attachment screws 84 so as to cover these LED lighting device bodies 100 to 103, and a power supply line for supplying power to each LED lighting device 10 83.

  Each LED lighting device body 100 to 103 uses one circuit board corresponding to the integrated base 11 of the LED lighting device 10, and a plurality of LED light sources 12 and a plurality of equalizing optics are provided on the circuit board. The body 13 is installed. Therefore, the LED lighting device bodies 100 to 103 correspond to a first group to a fourth group each including the plurality of LED lighting devices 10.

Here, the optical axes X ₁₀₀ , X ₁₀₁ , X ₁₀₂ and X ₁₀₃ of the irradiation light emitted from the LED lighting device bodies _{100 to 103} are angles θ ₁₀₀ , θ ₁₀₁ , θ ₁₀₂ and θ _{103 with} respect to the z axis, respectively. Make. The installation angle of the installation surface of the housing 81 is such that the angle of the optical axis of the installed LED lighting device bodies _{100 to 103} is as follows: (7) θ ₁₀₀ (> 0) = − θ ₁₀₃ > θ ₁₀₁ (> 0) = −θ ₁₀₂
Designed to have

By adjusting these angles θ _{100 to} θ ₁₀₃ , the irradiation angle of the irradiation light emitted from the entire LED lighting device 8 can be arbitrarily set within a considerably wide range, and further, the set irradiation is set. Irradiation light with sufficiently high illuminance can be supplied within the angular range. This also makes it possible to reduce the height difference of the illuminance in the entire illumination area of the apparatus 8 and to reduce the power consumption required to ensure the necessary minimum illuminance. In addition, it is also preferable that these angles θ _{100 to} θ ₁₀₃ are adjusted so that the illumination shapes of the irradiation lights from the LED lighting device bodies _{100 to 103} are arranged adjacent to each other or partially overlapping.

  In addition, it is also preferable that the LED lighting device bodies 100 and 103 arranged on the outer side emit emitted light having a smaller light distribution angle as compared with the inner LED lighting device bodies 101 and 102. When such an LED lighting device 8 is used, for example, for lighting a road or a road, the central region between the lighting devices that tends to have low illuminance is illuminated with light emitted from the LED lighting device bodies 100 and 103. Illuminance can be supplemented. This makes it possible to make the illuminance distribution in the longitudinal direction of the road or road more uniform.

  Further, the uniformizing optical body 13 of the LED lighting device 10, particularly the microlens array unit 131, can employ any of the various embodiments described above (Examples 1 to 3), and the uniformization is promoted. Furthermore, it is possible to emit outgoing light with controlled illuminance and illumination shape. Here, in the LED lighting device in which a plurality of LED lighting device rows such as the above-described device 8 are arranged in parallel, the substantially rectangular or substantially square-shaped emitted light is combined to form not only a substantially rectangular shape but also a substantially square shape. It is also possible to form irradiation light.

[LED lighting device 9]

  FIG. 13 is a front view and a sectional view showing still another embodiment of the LED lighting device according to the present invention. Here, FIG. 13B shows a cross section taken along the line D-D in FIG. FIG. 13C shows a cross section of the modified embodiment of FIG. Further, FIG. 13D shows a cross section taken along the plane EE of FIG.

  According to FIGS. 13A and 13B, the LED lighting device 9 includes a housing 91 and two circuits that are installed on the installation surface of the housing 91 and each serve as a plurality of bases 11. A board 110, a plurality of LED light sources 12 arranged in a line at predetermined intervals on each circuit board 110, and a uniform installed on the two circuit boards 110 so as to cover these two rows of LED light sources 12 13A, the cover 92 attached to the upper part of the housing 91 using the attachment screws 94 so as to cover the uniform optical assembly 13A, and a power source for supplying power to each LED lighting device 10 Line 93.

Homogenizing optical assembly 13A includes a plurality of homogenizing optical element 13 arranged in two rows, so as to form an angle theta _13A between rows is an optical member which is integrated into one. Therefore, the homogenizing optical assembly 13A, the plurality of LED light sources 12, and the two circuit boards 110 correspond to a first group and a second group each including a plurality of LED illumination devices 10 arranged in a line.

Here, the irradiation light emitted from the LED illumination device 9 includes the first irradiation light emitted from the first group (first row) of LED illumination devices 10 and the second group (second row) of LED illumination devices. 10 and the second irradiation light emitted from 10. A first irradiation light optical axis _{X 13A1} and the second irradiation light optical axis _{X 13A2,} in the yz plane, the angle _{(8) θ 9xA = π-} θ 13A ( in radians)
They are leaning from each other. In the present embodiment, θ _13A is less than π (180 °) (thus θ _9xA > 0).

As will be described in detail later, the angle θ _9xA formed by the optical axis is obtained by _{aligning the} illumination shape by the first irradiation light and the illumination shape by the second irradiation light adjacent to each other or partially overlapping each other. It is adjusted so as to form an illumination shape by irradiation light.

  FIG. 13C shows a change mode in the uniform optical assembly (and the housing) in FIG. According to FIG. 13C, two circuit boards 110 are installed on the installation surface of the casing 91B, and a plurality of LED light sources 12 are installed in a line at predetermined intervals on each circuit board 110. . Furthermore, the homogenizing optical assembly 13B is installed on the circuit board 110 so as to cover the two rows of LED light sources 12.

The equalizing optical assembly 13B is a plurality of homogenizing optical element 13 arranged in two rows, so as to form an angle theta _13B between rows is an optical member which is integrated into one. Therefore, the homogenizing optical assembly 13B, the plurality of LED light sources 12, and the two circuit boards 110 correspond to a first group and a second group, each including a plurality of LED lighting devices 10 arranged in a line.

Here, the irradiation light emitted from the entire apparatus is from the first irradiation light emitted from the first group (first row) LED illumination devices 10 and from the second group (second row) LED illumination devices 10. It is divided into the emitted second irradiation light. A first irradiation light optical axis _{X 13B1} and the second irradiation light optical axis _{X 13B2,} in the yz plane, the angle _{(9) θ 9xB = θ 13B} -π ( radians)
They are leaning from each other. In the present embodiment, θ _13B is a value exceeding π (180 °) (thus, θ _9xB > 0).

The first irradiating light and the second irradiating light are emitted from the uniformizing optical assembly 13B, then propagate with their optical axes intersecting (while overlapping each other), and then radiated away from each other. Is done. As will be described in detail later, the angle θ _9xB formed by the optical axis is determined by _{aligning the} illumination shape of the first irradiation light and the illumination shape of the second irradiation light adjacent to each other or partially overlapping each other. It is adjusted so as to form an illumination shape by irradiation light.

  FIG. 13D shows a cross section taken along the line E-E in FIG. 13B (the plane F-F in FIG. 13C). According to FIG. 13D, a circuit board 110 serving as a plurality of bases 11 is provided in a housing 91 (91B), and a plurality of LED light sources 12 are arranged on the circuit board 110 at predetermined intervals. is set up. Further, the uniformized optical assembly 13A (13B) is installed on the circuit board 110 so as to cover the plurality of LED light sources 12 installed. Further, the cover 92 (92B) covers the uniform optical assembly 13A (13B).

  As described above, the cover 92 protects the uniform optical assemblies 13A and 13B. The surface of the cover 92 has a water-repellent or oil-repellent coating agent containing a fluororesin or the like, or a self-cleaning function. It is also preferred to protect the surface of the LED lighting device 9 (cover 92) by applying a hydrophilic coating agent or the like having a coating film. Here, the self-cleaning function refers to a function in which even if dust, dust, fats and oils, contaminants, etc. in the atmosphere adhere to the coat film, the deposits are washed away by running water such as subsequent rainfall.

  As described above, by using the circuit board 110, the plurality of LED light sources 12, and the uniformizing optical assembly 13A, it is easier and simpler than connecting the plurality of LED lighting devices 10. The first group (second group) corresponding to the plurality of LED lighting devices 10 can be configured with higher accuracy.

[LED lighting device 9 ']

  FIG. 14 is a front view and a sectional view showing still another embodiment of the LED lighting device according to the present invention. Here, FIG. 14B shows a cross section taken along the line F-F in FIG. FIG. 14C shows a cross section taken along the line G-G in FIG.

  According to FIGS. 14A and 14B, the LED lighting device 9 ′ includes a housing 91 ′, four heat dissipating portions 19 installed on the installation surface of the housing 91 ′, and four heat dissipating portions. 19, four circuit boards 110, each of which serves as a plurality of bases 11, a plurality of LED light sources 12 arranged in a line at predetermined intervals on each circuit board 110, and these Two uniformizing optical assemblies 13C installed on the circuit board 110 so as to cover two rows of the LED light sources 12 respectively, and a power supply line 94 ′ for supplying power to each LED lighting device 10 I have.

  The two uniformized optical assemblies 13C, the plurality of LED light sources 12, and the four circuit boards 110 correspond to a first group to a fourth group each including a plurality of LED illumination devices 10 arranged in a line. Become.

Here, the optical axes X _13C1 , X _13C2 , X _13C3, and X _13C4 of the irradiation light emitted from the two homogenizing optical assemblies 13C have angles θ _13C1 , θ _13C2 , θ _13c3, and θ with respect to the z axis, respectively. Make _13C4 . The installation surface of the casing 91 ′ has the following relationship between the angles of these optical axes in the installed circuit board 110 (homogenized optical assembly 13C):
(10) θ _13C1 (> 0) = − θ _13C4 > θ _13C2 (> 0) = − θ _13c3
Designed to have

By adjusting these angles θ _{13C1 to} θ _13C4 , the irradiation angle of the irradiation light emitted from the entire LED lighting device 9 ′ can be arbitrarily set within a considerably wide range, and further set. Irradiation light with sufficiently high illuminance can be supplied within the irradiation angle range. The angles θ _{13C1 to} θ _13C4 are preferably adjusted so that the illumination shapes of the irradiation lights from the two homogenizing optical assemblies 13C are arranged adjacent to each other or partially overlapping.

  It is also possible to integrate the two uniform optical assemblies 13C into one uniform optical assembly. In any case, as a method of forming the homogenized optical assemblies 13A to 13C including the one shown in FIG. 13, an acrylic resin, polycarbonate resin, cycloolefin polymer resin, cyclic olefin resin, optical A method of injecting and curing an optically transparent resin such as a silicone resin, an optical special polyester resin, or a high-density polyethylene resin, or a transparent optical glass or fluorescent glass can be employed. Thereby, the uniformized optical assemblies 13A to 13C can be stably mass-produced and can be manufactured at low cost. Further, the number of parts at the time of device assembly is reduced, and the optical system of the LED lighting apparatus is completed by simply attaching the integrated uniform optical assembly to the base 11 or the circuit board 110.

  Further, the two homogenizing optical assemblies 13C are sealed at the periphery by seal members 940 'and 941' and holding frames 920 'and 921' for suppressing the seal members 940 'and 941', respectively. Here, the holding frames 920 ′ and 921 ′ are tightened to the mounting screws 930 ′ and 931 ′, respectively, thereby pressing the seal members 940 ′ and 941 ′ against the uniformizing optical assembly 13 </ b> C. As a result, the airtightness / dustproofness and the waterproofness / moistureproofness of the LED lighting device 9 ′ are ensured.

  The casing 91 'is made of a metal material such as aluminum die cast or stainless steel, or an opaque plastic material including polycarbonate, PET, acrylic, or the like, and is opaque. The casing 91 'may be formed by sheet metal processing. The heat dissipating part 19 is preferably a plate-like material formed of a metal material such as aluminum or copper, or a heat conductive sheet (or a laminate thereof) such as silicone, acrylic, graphite or inorganic.

  FIG. 14C illustrates a cross section taken along the line HH in FIG. According to FIG. 14C, the heat radiating part 19 is provided on the casing 91 ′, the circuit board 110 serving as the plurality of bases 11 is provided on the heat radiating part 19, and the plurality of LED light sources 12 are The circuit boards 110 are installed at predetermined intervals. Further, the uniformizing optical assembly 13C is installed on the circuit board 110 so as to cover the plurality of LED light sources 12 installed.

  In this way, the two uniformized optical assemblies 13C also serve as a cover in the LED lighting device 9 '. Therefore, a coating film is formed on the surface of the homogenizing optical assembly 13C by applying a water-repellent or oil-repellent coating agent containing a fluororesin or the like, or a hydrophilic coating agent having a self-cleaning function. It is also preferable to protect the surface of the aggregate 13C.

  As described above, by using the circuit board 110, the plurality of LED light sources 12, and the uniformizing optical assembly 13C, it is easier and simpler than connecting the plurality of LED lighting devices 10. The plurality of LED lighting devices 10 forming the first group to the fourth group can be configured with higher accuracy. Further, since the uniformized optical assembly 13C also serves as a cover for the apparatus 9 ', it is not necessary to provide a new cover, and the manufacturing becomes easier.

  Moreover, LED lighting device 7, 8, 9 and 9 'demonstrated in FIGS. 11-14 is provided with the several group which consists of several LED lighting device 10, and the irradiation light from each group mutually adjoins or partially overlaps. It is set to be. As a result, it is possible to realize irradiation light having a sufficiently high illuminance, a sufficiently large irradiation angle, and a controlled illumination shape. Such irradiation light is suitable for illumination of the road surface or floor surface of a road or a passage, as will be described later. Furthermore, it is very suitable for an illumination target such as a road that needs to be illuminated over a very long distance while the height is limited.

  The arrangement / number of rows formed by the plurality of LED lighting devices 10 in each of the LED lighting devices 7, 8, 9 and 9 'is not limited to that described above. For example, the LED lighting device 7 (FIG. 11) can include two or more rows of LED lighting devices 10 on each of the first and second installation surfaces 710 and 711. Further, the LED lighting device 9 ′ (FIG. 14) may include five or more groups (rows) of the LED lighting devices 10 having different optical axis directions.

[Lighting of roads, passages or roads by LED lighting device 7]

  FIG. 15 is a schematic diagram for explaining an embodiment related to the installation of the lighting device 7 in the longitudinal direction of the road (or passage) 5 or the road 6. Also in this embodiment, the LED lighting device 10 of the LED lighting device 7 adopts, for example, the same form as in the first or third embodiment, and the illumination area 380 of the LED lighting device 7 is substantially rectangular. (Or substantially square shape).

FIG. 15A shows the installation of the lighting device 7 in the longitudinal direction of the road (or passage) 5. According to the figure, the LED illumination devices 7 are arranged with a distance D ₇ in the longitudinal direction of the road 5. Here, the LED illumination device 7 is inclined at an angle θ _el in the ZX plane, similarly to the LED illumination device 1 shown in FIG. The arrangement direction of the LED lighting devices 10 in the LED lighting device 7 (longitudinal direction of the LED lighting device 7) is also in the ZX plane.

The irradiation light 38 radiated from the LED illumination device 7 is formed such that the irradiation light 38a radiated from the first group 10f and the irradiation light 38b radiated from the second group 10s are adjacent or partially overlapped. . As shown in FIG. 15A, when an illumination area of the irradiation light 38 is a combination of the illumination area of the irradiation light 38a and the illumination area of the irradiation light 38b, the irradiation angle γ of the irradiation light 38 in the YZ plane is When the irradiation angle in the YZ plane of the irradiation light 38a and the irradiation light 38b is β,
(11) β <γ ≦ 2β
The irradiation angle γ of the irradiation light 38 emitted from the entire LED lighting device 7 can be arbitrarily set within a considerably wide range, and is sufficiently high within the set irradiation angle range. Illuminance illumination light can be provided.

  Further, the end in the longitudinal direction (Y-axis direction) of the road surface 50 having the lowest illuminance in the formed illumination area 380 overlaps with the end of the adjacent illumination area 380 to form an overlap area 380v. . As a result, even if there is an area where the required minimum illuminance is not secured in the illumination area 380 alone, the adjustment is made so that the necessary minimum illuminance can be secured in the overlapping area 380v, so that it is necessary on the entire road surface 50. It is possible to secure a sufficient illuminance.

  In addition, the illuminance tends to be insufficient in the central region in the longitudinal direction between the adjacent LED lighting devices 7. In order to cope with this, it is also preferable to mix LED lighting devices 10 having a smaller light distribution angle (long focal length) in each of the first group 10f and the second group 10s of the LED lighting device 7. This makes it possible to supplement the central area with illuminance and make the illuminance distribution in the longitudinal direction of the road 5 more uniform. Moreover, when required illumination intensity is ensured only by the illumination area | region 380, adjacent illumination areas may mutually be arrange | positioned mutually.

FIG. 15B shows a state of installation of the LED lighting device 7 in the longitudinal direction of the path 6. According to the figure, the LED illumination devices 7 are arranged with a distance D ₇ ′ in the longitudinal direction of the path 6. The arrangement direction of the LED lighting devices 10 in the LED lighting device 7 is the width direction (X-axis direction) of the path 6.

  Furthermore, the irradiation angle γ ′ of the irradiation light 39 emitted from the LED lighting device 7 can be set to a sufficiently large value, similarly to the irradiation angle γ of FIG. In addition, the end in the longitudinal direction (Y-axis direction) of the floor surface 60 having the lowest illuminance in the illumination area 390 overlaps with the end of the adjacent illumination area 390 to form an overlap area 390v. As a result, the irradiation light 39 secures necessary illuminance over a very long distance in the longitudinal direction of the path 6 on the side surface including the floor surface 60 and the cable shelf 61 in the path 6 where the height is limited, Moreover, it is possible to illuminate without waste.

  In addition, also on the road 6, the central region in the longitudinal direction between the adjacent LED lighting devices 7 tends to have insufficient illuminance. In order to cope with this, it is also preferable to mix LED lighting devices 10 having a smaller light distribution angle (long focal length) in each of the first group 10f and the second group 10s of the LED lighting device 7. This makes it possible to supplement the central area with illuminance and make the illuminance distribution in the longitudinal direction of the path 6 more uniform.

  As described above, the illumination method described in FIGS. 15A and 15B has been described on the assumption that the LED illumination device 7 is used. However, the illumination method is not limited to this, and the LED illumination devices 8, 9 or Even if 9 ′ is used, it is possible to irradiate road surface 50 or floor surface 60 with irradiation light having a sufficiently large irradiation angle and sufficiently high illuminance while controlling the illumination shape. As a result, it is possible to realize illumination with no illuminance in which illuminance required according to the illumination target of the road (passage) 5 and the road 6 is ensured, and color unevenness is suppressed. In particular, by using the LED illumination device 8 or 9 ', the irradiation angle of the irradiation light can be set larger. As a result, it is possible to further widen the installation interval of the devices in the longitudinal direction of the road (passage) 5 or the road 6, and it is possible to perform illumination while ensuring necessary illuminance even in a section having a severe height restriction.

  In particular, in the road 6, the height of the ceiling is often about 2.4 m, for example. In this case, there is no great difference between the height of the lighting device in the trail 6 and the height of the eyes of the worker. As a result, in the conventional illuminating device, strong light from the illuminating device directly enters the eyes of the operator and is very dazzling. On the other hand, as described above, this problem can be solved by using the LED lighting device 7 in which the LED lighting device 10 having a smaller light distribution angle is mixed in each of the first group 10f and the second group 10s. The That is, since the LED illumination device 10 having a long focal length with a small light distribution angle is used in the central region between the adjacent LED illumination devices 7, almost no light is incident on the operator's eyes and glare is reduced. Further, even in the vicinity immediately below the LED lighting device 7, the dispersed irradiation light having a large light distribution angle can be obtained, so that the glare is reduced.

  Here, FIG. 15C is used to show conditions under which the irradiation light 38 is formed from the irradiation light 38a and the irradiation light 38b in FIG. 15A. It should be noted that the following calculation is an approximate calculation in which the irradiation light 38a and the irradiation light 38b are emitted from the same point light source.

As shown in FIG. 15C, the irradiation angle of each of the irradiation light 38a and the irradiation light 38b is β, and the angle formed by the first installation surface 710 and the second installation surface 711 (FIG. 11) of the housing 71 is θ. ₇₁ . At this time, the angle θ _7x formed by the optical axes X _10f and X _{10s of} the irradiation light 38a and the irradiation light 38b, respectively, is expressed by Equation (6): θ _7x = π−θ ₇₁ .

Therefore, when the angle in the YZ plane of the light beam forming the overlapping region 380ab of the irradiation light 38a and 38b is θ _380ab ,
(12) θ _380ab = 2 · (β / 2− (π−θ ₇₁ ) / 2)
= Β + θ ₇₁ −π
It becomes. Here, the condition in which the irradiation light 38a and the irradiation light 38b are adjacent to each other or partially overlapped is θ _380ab ≧ 0.
(13) β ≧ π−θ ₇₁
It becomes. That is, by setting the irradiation angles β of the irradiation light 38a and the irradiation light 38b to values satisfying the expression (13), a sufficiently large irradiation angle γ
(14) γ = 2β−θ _380ab
= Β + π−θ ₇₁
It is possible to realize the irradiation light 38 having the following.

  In any case, in the microlens array unit 131 in the LED illumination device 7, the curvature radius R and pitch P of the plurality of microlenses 131m, or both the curvature radius R and pitch P are determined in the lens array surface 131a. Different values are set and controlled between directions. As a result, the light distribution angle (or FWHM) in the ZX plane and the light distribution angle (or FWHM) in the YZ plane in the emitted light of the LED lighting device 10, and further in the irradiation light of the LED lighting device 7 The irradiation angle in the ZX plane and the irradiation angle in the YZ plane can be independently controlled. Therefore, the range of the illumination region 380 (390) in the width direction (X-axis direction) of the road 5 or the road 6 and the range of the illumination region 380 (390) in the longitudinal direction (Y-axis direction) of the road 5 or the road 6 Are individually controllable. Thereby, the illumination area (illumination shape) suitable for the road surface 50 or the floor surface 60 can be realized in both the width direction and the longitudinal direction of the road surface 50 or the floor surface 60.

  FIG. 16 is a schematic diagram for explaining another embodiment according to the illumination method in the longitudinal direction of the path 6. Also in this embodiment, the LED lighting device 10 of the installed LED lighting device adopts, for example, the same form as in Example 1 or 3, and the illumination area 400 of the LED lighting device 7 is substantially the same. It is set to have a rectangular shape (or a substantially square shape).

FIG. 16A shows a state of installation of the LED illumination device 7 in the longitudinal direction (Y-axis direction) of the path 6. According to the figure, a group of two LED lighting devices 7 are arranged with a distance D ₇₇ in the longitudinal direction of the path 6. Here, each of the two LED illuminating devices 7 forming a group is installed so as to have a tip portion at an angle θ ₇₇ with respect to the floor surface 60 in the YZ plane. Therefore, the plurality of LED lighting devices 10 constituting each LED lighting device 7 are arranged in the YZ plane.

In addition, the emission surfaces of the plurality of LED illumination devices 10 in each LED illumination device 7 form an angle θ ₇₇ with respect to the floor surface 60 in the YZ plane. As a result, the optical axis of the irradiation light from the first group 10f (second group 10s) of the LED lighting device 10 is inclined by the angle θ _{77 with} respect to the normal line of the floor surface 60 in the YZ plane.

  Furthermore, the irradiation light 40 radiated from the entire group of the two LED lighting devices 7 is formed such that the irradiation light radiated from each of the LED lighting devices 7 is adjacent or partially overlapped. As a result, the irradiation light 40 can have a sufficiently large irradiation angle, and irradiation light with a sufficiently high illuminance can be provided in the illumination region 400.

  Further, the end in the longitudinal direction (Y-axis direction) of the floor surface 60 having the lowest illuminance in the illumination area 400 formed by the irradiation light 40 overlaps with the end of the adjacent illumination area 400, and the overlap area 400v is formed. As a result, even if there is an area where the required minimum illuminance is not ensured in the illumination area 400 alone, adjustment is performed so that the necessary illuminance can be ensured in the overlapping area 400v. Illuminance can be secured. In addition, when required illumination intensity is ensured by the illumination area 400 alone, the adjacent illumination areas 400 may be arranged adjacent to each other.

  Here, the illumination area 400 extends to the floor surface 60 of the path 6 and the lower part of the side surface including the position of the cable shelf 61. By making the illumination shape of the illumination area 400 substantially rectangular, it is possible to illuminate all the cable shelves 61 extending along the longitudinal direction (Y-axis direction) of the path 6 without waste.

FIG. 16B shows an illumination method using the LED illumination device 95 in the longitudinal direction (Y-axis direction) of the path 6. According to the figure, a plurality of LED lighting devices 10 are arranged in the longitudinal direction of the path 6 in the LED lighting device 95. The optical axes X _{950 to} X ₉₅₄ of the emitted light radiated from these LED lighting devices 10 extend in the direction of separating (diverging) from each other toward the floor surface 60 in the YZ plane. As a result, the irradiation light 41 from the LED lighting device 95 can have a sufficiently large irradiation angle, and irradiation light with sufficiently high illuminance can be provided to the illumination region 410.

In addition, the distribution of the directions of the optical axes X _{950 to} X ₉₅₄ in the plurality of LED lighting devices 10 arranged in the longitudinal direction of the path 6 is not limited to the form shown in FIG. Further, the number of the LED lighting devices 10 arranged in one row is not limited to the form (five) shown in FIG. For example, the LED lighting device 10 having the optical axis having the first direction in the YZ plane and the LED lighting device 10 having the optical axis having the second direction are alternately arranged and arranged in one row. May be.

  FIG. 16C shows an illumination method using the LED illumination device 96 in the longitudinal direction (Y-axis direction) of the path 6. According to the figure, a plurality of LED lighting devices 10 form one row in the longitudinal direction of the path 6 in the LED lighting device 96. Among these LED lighting devices 10, the LED lighting devices 10 a and 10 c that emit emitted light that bears the end portion or the vicinity of the end portion in the longitudinal direction of the illumination region 420 by the irradiation light 42 are the center portion or the vicinity of the center portion of the illumination region 420. The LED illumination device 10b that emits the emitted light that bears the emission light is set to emit the emitted light having a smaller light distribution angle.

  Here, in general, emitted light having a smaller light distribution angle provides higher illuminance in an illumination area at a certain distance from the light source. In other words, the degree of light dispersion is small, and illumination with high illuminance is possible even further away. Therefore, in the illumination area 420 by the illumination light 42, a sufficiently high illuminance can be realized even at the end in the longitudinal direction (Y-axis direction). This makes it possible to reduce the height difference of the illuminance in the entire illumination area and to reduce the power consumption required to ensure the necessary minimum illuminance.

  Moreover, it is preferable that the light distribution angles in the ZX plane of the emitted light from each of the LED lighting devices 10a to 10c are equal to each other. Thereby, the width in the width direction (X-axis direction) of the path 6 in the illumination area of these emitted lights is made the same, and the side surface of the path 6 including the cable shelf 61 is extended along the longitudinal direction (Y-axis direction). It is possible to reliably illuminate at a certain height. When the cross section of the internal space of the path 6 is substantially circular, the width (in the X-axis direction) of the illumination area of these emitted lights can be about the diameter of this circle.

  Furthermore, as another embodiment, in FIGS. 16A to 16C, the output of the emitted light can be changed for each LED lighting device 10. For example, the output (input power) of the LED illumination device that emits the emitted light that bears the end in the longitudinal direction of the illumination shape formed by the irradiation light or the vicinity of the end is the emitted light that bears the center or near the center of the illumination shape. It is also preferable to make it higher than the output (input power) of the LED lighting device that emits light. Thereby, the height difference of the illumination intensity in the whole illumination area | region can be made small.

  As described above, in the embodiment of the illumination method shown in FIGS. 8, 9, 10, 15, and 16, the road (or passage) 5 or the road 6 is the illumination target, but the illumination target is not limited to this. . The illumination method of the present invention can also be applied to illumination of a region extended to a predetermined distance with a constant or a width within a predetermined range.

  Furthermore, in the embodiment of the illumination method shown in FIGS. 8, 9, 10, 15 and 16, the illumination shape of the illumination area is substantially rectangular or square. However, the present invention is not necessarily limited to these. For example, as shown in FIG. 6B, a longitudinal direction (X-axis) formed by arranging substantially elliptical shapes or substantially circular shapes partially overlapping each other. It may be a rectangular shape with curved ends. Here, by overlapping a sufficient number of substantially elliptical shapes (substantially circular shapes), the rectangular shape with curved both ends can be made a substantially rectangular shape. However, it is possible to realize irradiation light that is closer to a rectangular shape (square shape) by combining substantially rectangular or square-shaped emitted light, and it is possible to perform lean illumination more suitable for a rectangular illumination target. .

[Example of Todoroki Lighting: LED lighting device 97]

  FIG. 17 is a top view (FIG. 17A), a front view (FIG. 17B), and a bottom view (FIG. 17) showing an LED illumination device used in an example in which a road is illuminated by the illumination method of the present invention. 17 (C)) and cross-sectional views (FIGS. 17D1 to D3). Here, FIG. 17D1 shows a cross section taken along the HH plane in FIG. 17B, FIG. 17D2 shows a cross section taken along the II plane in FIG. 17B, and FIG. D3) shows a cross section taken along the JJ plane and the KK plane of FIG.

  17A to 17C, the LED lighting device 97 is attached to a case 970 made of aluminum die cast (or made of sheet metal), an attachment support 973, and the case 970 and the attachment support 973. A plurality of angle setting holders 972A, 972B and 972C, LED lighting devices 10A, 11B and 11C attached to the angle setting holders 972A, 972B and 972C, a mother circuit board 974, an AC / DC converter 976, A secondary battery 971 and an optically transparent plastic cover 975 are provided.

  The secondary battery 971 is an emergency power source. When the supply of AC power from the outside is stopped due to a disaster or accident, the control circuit provided on the mother circuit board 974 automatically sets the secondary power supply source to the secondary power source. Switch to battery 971. In FIG. 17A, the secondary battery 971 is externally attached, but can be installed inside the housing 970 as indicated by 971 '. The AC / DC converter 976 is installed inside the housing 970, and converts alternating current (100V or 200V) taken in via the cable 977 and the waterproof connector into direct current (for example, 12V).

  The cover 975 is attached to the housing 970 in such a manner that the cover 975 is pressed against an O-ring attached to a groove provided in the housing 970 (not shown) for waterproofing inside the housing. Yes. The orientation of the surface of the cover 975 is adjusted to be as perpendicular as possible to the optical axes of the LED lighting devices 10A, 10B, and 10C in order to suppress reflection of emitted light.

  Four LED lighting devices 10A and eight LED lighting devices 10B and 10C are provided, respectively. Two rows are arranged in the order of 10C, 10C, 10B, 10B, 10A, 10A, 10B, 10B, 10C and 10C. Configure. Here, the LED lighting device 10A and the LED lighting devices 10B and 10C have different optical characteristics as described later.

  The LED lighting devices 10A, 10B, and 10C include circuit boards (or circuit sheets) 110A, 110B, and 110C that function as a plurality of bases 11, respectively, and are installed in angle setting holders 972A, 972B, and 972C, respectively. The circuit boards 110 </ b> A, 110 </ b> B, and 110 </ b> C are supplied with controlled power from the mother circuit board 974 through wiring that passes through the mounting support 973.

  It is also possible to use a homogenizing optical assembly in which the homogenizing optical bodies 13 of the two LED lighting devices 10A (10B or 10C) are integrally formed, and to install this in the angle setting holder 972A (972B or 973C). It is.

The angle setting holders 972A, 972B, and 972C have a mechanism that allows the installation angle of the LED lighting device to be freely set. In the present embodiment, as shown in FIGS. 17D1 to 17D3, the optical axes _X10A , _X10B, and _X10C ( _X10C ′) of the LED lighting devices 10A, 10B, and 10C are formed with respect to the z-axis. The angles θ _10A , θ _10B and θ _10C are
θ _10A = 50 ° (degrees)
θ _10B = 62.5 °
θ _10C = 79.5 °
Is set to

Furthermore, as shown in FIG. 17C, the angle setting holder 972C is further inclined to lift one side, and the optical axis X _10C (X _10C ′) of the LED lighting device 10C is formed with respect to the y-axis. The angle θ _SIDE is
θ _SIDE = 9 °
Is set to Here, the optical axes X _10C (X _10C ′) of the eight LED lighting devices 10C all extend outside the apparatus, that is, in a direction away from the LED lighting device 10A at the center of the apparatus.

In addition, four LED light sources 12A are provided at the lower end of the mounting support 973. The optical axis _{X 12A} of the LED light source 12A is extended in the z-axis direction, the LED light source 12A illuminates the area immediately below the device. In addition, the circuit board (or circuit sheet) 110D of the LED light source 12A is supplied with controlled electric power from the mother circuit board 974 through a wiring passing through the mounting support 973.

  The LED illumination device 97 includes a total of 20 LED illumination devices 10A, 10B, and 10C having different roles with respect to the illumination area in two rows at the same height with respect to the z axis. As a result, the thickness of the device in the z-axis direction becomes smaller and the device is downsized.

  FIG. 18 is a schematic diagram illustrating the orientation of the LED lighting devices 10A, 10B, and 10C in the LED lighting device 97, and a schematic diagram illustrating the direction of the optical axis of the LED lighting devices 10A, 10B, and 10C.

According to FIG. 18 (A), in one row of LED lighting devices 10A, 10B and 10C arranged in the order of 10C, 10C, 10B, 10B, 10A, 10A, 10B, 10B, 10C and 10C, light It can be seen that the directions of the axes X _10C , X _10B and X _10A also change sequentially as shown below.
(A) LED lighting device 10C: θ _10C = 79.5 °, θ _SIDE = 9 ° (-x direction)
(B) LED lighting device 10B: θ _10B = 62.5 °
(C) LED lighting device 10A: θ _10A = 50 °
(D) LED lighting device 10C: θ _10C = 79.5 °, θ _SIDE = 9 ° (+ x direction)

  FIG. 18B shows a mode in which the LED lighting device 97 is installed on the ceiling of the road 6 which is the illumination target of this embodiment. In the figure, the size of the inside of the path 6 and the direction of the optical axis of the LED lighting devices 10A, 10B and 10C are shown.

  As shown in FIG. 18B, the plurality of LED lighting devices 97 are installed on the ceiling of the road 6 at the center in the width direction (X-axis direction) with an interval of 10 m in the longitudinal direction (Y-axis direction). Has been. At this time, the longitudinal direction (x-axis direction) of the LED lighting device 97 is set to the width direction (X-axis direction) of the path 6. Further, the height in the road 6 is 2.4 m. The LED lighting device 97 can also be suspended from the ceiling.

Irradiation light of the LED illumination device 97 includes emission light emitted from each of the LED illumination devices 10A, 10B, and 10C and emission light from the LED light source 12A. Of these, the optical axis _{X 12A} of light emitted from the LED light source 12A is, extends from the LED lighting device 97, reaches a point _{P 97} immediately below the LED illumination apparatus 97.

Further, the optical axis X _10A of the emitted light from the LED lighting device 10A extends from the LED lighting device 97, and is a midpoint P _MID between the devices in the longitudinal direction (Y-axis direction) on the floor surface 60 of the path 6. When reaching a position between the point _{P 97} immediately below the LED illumination apparatus 97. Further, the optical axis _{X 10B} of the light emitted from the LED lighting device 10B decompresses the LED lighting device 97, reaches a point beyond the middle point _{P MID} between devices.

Furthermore, the optical axis _{X 10C} of the light emitted from the LED lighting device 10C from LED lighting device 97, also extending beyond the point _{P 97} immediately below next to the LED lighting device 97. Here, the optical axes X _10C and X _10C ′ of the LED lighting device 10C are inclined in the −x direction and the + x direction, respectively, with the angle θ _SIDE = 9 ° as described above, and each side surface 60s of the path 6 is 60s. And the other side surface 60s.

That is, the above is summarized:
a) LED light source 12A illuminates mainly point _{P 97} immediately below device.
b) LED lighting device 10A illuminates mainly the area between the midpoint _{P MID} between the equipment and the point _{P 97} immediately below device.
c) The LED lighting device 10B illuminates centering on a region beyond the midpoint P _MID between the devices.
d) The LED lighting device 10 </ b> C illuminates around both side surfaces 60 s of the path 6.

[Example of way illumination: Optical characteristics of LED lighting devices 10A, 10B, and 10C]

  FIG. 19 is a graph showing characteristics of emitted light emitted from the LED lighting devices 10A, 10B, and 10C. The irradiation experiment with the emitted light is performed by optical simulation.

First, the LED lighting devices 10B and 10C will be described. The microlenses 131m of these devices are arranged in a rectangular shape. The radii of curvature R _{x ′} and R _{y ′} are both equal to 1.0 mm. The pitches P _{x ′} and P _{y ′} between the microlenses are 1.7 mm and 0.6 mm, respectively, and the pitch P has anisotropy. That is, the microlenses 131m of the LED lighting devices 10B and 10C are anisotropic microlenses having different pitches P. The x ′ axis and the y ′ axis comply with the coordinate system shown in FIGS.

FIG. 19A1 shows the luminous intensity distribution of the emitted light from the LED lighting devices 10B and 10C. Here, according to the figure, the luminous intensity distributions are different Gaussian distributions in the x′-axis direction and the y′-axis direction. The full widths at half maximum F _{x ′} and F _{y ′} are 34.0 ° and 19.3 °, respectively, which are different values.

  FIG. 19A2 shows the illuminance distribution in the x′y ′ plane of the light emitted from the LED lighting devices 10B and 10C, and FIG. 19A3 shows the light emitted from the LED lighting devices 10B and 10C. The illuminance distribution in the x′-axis direction and y′-axis direction is shown. Here, the illuminance distribution in both figures is a distribution on a plane (perpendicular to the optical axis) at a position of 2.4 m (corresponding to the height of the path) along the optical axis from the microlens array part 131. is there.

  As shown in FIG. 19 (A2), since the LED illumination devices 10B and 10C use anisotropic microlenses having different pitches P, the illumination shape of the emitted light has a long side in the x′-axis direction. It is controlled in a rectangular shape. Actually, as shown in FIG. 19A3, the illuminance distribution is greatly different between the x′-axis direction and the y′-axis direction. In this illumination shape, no distribution corresponding to the blue and yellow rings in the center is seen, and it is confirmed that the uniformization of the emitted light is promoted.

  Here, the LED lighting devices 10 </ b> B and 10 </ b> C are set so that the long side in the x′-axis direction in the substantially rectangular illumination shape is the width direction (X-axis direction) of the road 6.

Next, the LED lighting device 10A will be described. The microlenses 131m of the LED lighting device 10A are arranged in a square. The radii of curvature R _{x ′} and R _{y ′} are both equal to 1.0 mm. Further, the pitches P _{x ′} and P _{y ′} between the microlenses are both 1.4 mm and equal. That is, the micro lens 131m of the LED lighting device 10A is an isotropic micro lens. As a result, the full widths at half maximum F _{x ′} and F _{y ′} in the luminous intensity distribution are both 33.4 ° and are equal.

  FIG. 19B1 shows the illuminance distribution in the x′y ′ plane of the light emitted from the LED lighting device 10A. FIG. 19B2 shows the illuminance distribution in the x′-axis direction and the y′-axis direction of the light emitted from the LED lighting device 10A. The illuminance distribution in both figures is also a distribution on a plane (perpendicular to the optical axis) at a position of 2.4 m (corresponding to the height of the path) along the optical axis from the micro lens array part 131.

  As shown in FIG. 19 (B1), the LED illumination device 10A uses an isotropic microlens, so that the illumination shape of the emitted light is circular. Actually, the illuminance distributions substantially coincide in the x′-axis direction and the y′-axis direction as shown in FIG. In addition, no distribution corresponding to the blue and yellow rings in the center is observed in the illumination shape, and it is confirmed that the uniformization of the emitted light is promoted. In this embodiment, an isotropic microlens is used as the LED lighting device 10A, but anisotropic microlenses can be used as in the LED lighting devices 10B and 10C. It is.

Here, when the optical characteristics of the emitted light in the LED lighting devices 10A, 10B, and 10C described above are summarized,
a) The LED lighting device 10 </ b> A has a circular illumination shape and illuminates around a region between a point P ₉₇ directly below the device and a midpoint P _MID between the devices.
b) The LED lighting device 10B illuminates centering on a region beyond the middle point P _MID between the devices, but in accordance with the road width direction (X-axis direction) extending along the long side of the substantially rectangular illumination shape, It plays the role which raises illumination intensity to the both ends of 60 width directions.

c) The LED lighting device 10 </ b> C has a substantially rectangular illumination shape and illuminates around both side surfaces 60 s of the path 6. It has a small depression angle (θ _10C = 79.5 °) and an inclination (θ _SIDE = 9 °) from the longitudinal direction (Y-axis direction) to the side surface 60s, and illuminates a region close to the ceiling on the side surface 60s. . Thereby, the illuminance necessary for work can be secured even at the position of the cable shelf 61 installed near the ceiling of the side surface 60s.

  Further, the LED lighting device 97 emits irradiation light composed of light emitted from the LED lighting devices 10A, 10B, and 10C and light emitted from the LED light source 12A. The irradiation light from the LED illumination device 97 includes an illumination area portion having a certain width, and forms a substantially rectangular illumination area on the illumination target plane. Hereinafter, the Example which illuminated the inside of the road 6 using this LED lighting apparatus 97 is described with a comparative example.

[Example of way illumination: illumination of way 6 by LED illumination device 97]

  20 and 21 are graphs showing the illuminance distribution when the road 6 is illuminated by the LED illumination device 97. FIG. Here, the size of the inside of the road 6 and the installation state of the LED lighting device 97 are as shown in FIG. In this simulation, the amount of light flux of each of the LED light sources 12 and the LED light sources 12A of the LED lighting devices 10A, 10B, and 10C is calculated as 100 lm (lumen).

  FIG. 20A shows the illuminance distribution on the center line in the longitudinal direction (Y-axis direction) of the floor surface 60 of the road 6 and the illuminance distribution in the width direction (X-axis direction) of the floor surface 60. According to the figure, the illuminance distribution in the longitudinal direction is generally within the range of 30 to 55 lx. Moreover, the illuminance distribution in the width direction is generally within the range of 30 to 45 lx. Therefore, it can be seen that the variation in illuminance on the floor surface 60 is about twice as large as the ratio of the maximum value / minimum value. Note that the graph curve in FIG. 20A shows variations other than the original distribution due to the limitations of the simulation calculation time and the memory amount of the calculation hardware.

  Further, the minimum value of 30 lx in illuminance is significantly higher than the standard minimum illuminance (for example, 5 lx) required for a normal road. Further, the average illuminance on the center line of the floor surface 60 is 36.5 lx. This average illuminance is a value more than twice the reference average illuminance (for example, 15 lx) required for a normal road.

  Next, FIG. 20B shows a graph representing the illuminance distribution of FIG. 20A on the floor surface 60 (XY plane) of the road 6. According to the figure, the LED lighting device 97 illuminates the floor surface 60 extending in the Y-axis direction with a substantially uniform illuminance both in the longitudinal direction (Y-axis direction) and in the width direction (X-axis direction). I understand that

  Next, in FIG. 21A, the illuminance distribution in the longitudinal direction (Y-axis direction) at a position on the side surface 60s of the path 6 and 1.5 m above the floor surface 60, and above the floor surface 60. The illuminance distribution in the width direction (X-axis direction) at a position of 1.5 m is shown. Here, the position range of the illuminance distribution in the width direction includes a point immediately below the device 97. According to the figure, even at a position 1.5 m above the floor surface 60, an illuminance of at least a reference minimum illuminance (for example, 5 lx) required for a normal path is secured. Note that, in the graph of the illuminance distribution in the width direction in FIG. 21A, both ends of the graph have dropped to positions where the illuminance is zero. This is due to the convenience related to the setting of boundary conditions in the simulation. In practice, it should be noted that the illuminance in the width direction matches the illuminance in the longitudinal direction at a position on the side surface 60s.

  Next, FIG. 21B is a graph showing the illuminance distribution on the side surface 60s of the path 6 on the YZ plane. According to the figure, the LED illumination device 97 illuminates a range from the lower end of the side surface 60s extending in the Y-axis direction to a certain height (the height of the ceiling in the figure) with a substantially uniform illuminance. I understand that. Actually, a cable shelf 61 is provided on the side surface 60s of the path 6 and the LED lighting device 97 illuminates the cable shelf 61 with sufficient illuminance to work.

The reason that the LED lighting device 97 illuminates the side surface 60s of the path 6 substantially uniformly up to a certain height (the height of the ceiling in FIG. 21B) is mainly the outside at an angle θ _SIDE. By the outgoing light of the inclined LED lighting device 10C.

[Example of Todoroki illumination: Comparison with comparative example (fluorescent lamp illumination)]

  Here, a comparative example in which the path 6 is illuminated with a conventional fluorescent lamp will be described. The fluorescent lamp used for the simulation of this comparative example is 20 W. Here, the installation situation of the fluorescent lamp is that in FIG. 18B, the fluorescent lamp is installed in place of the LED illumination apparatus 97 at the installation position of the LED illumination apparatus 97. The fluorescent lamp is installed such that its longitudinal direction is parallel to the width direction (X-axis direction) of the path 6.

  FIG. 22 is a graph showing the illuminance distribution when the path 6 is illuminated with a fluorescent lamp (20 W).

  FIG. 22A shows the illuminance distribution on the center line in the longitudinal direction (Y-axis direction) of the floor surface 60 of the road 6. According to the figure, the illuminance distribution in the longitudinal direction varies approximately in the range of 4 to 32 lx, and there is a fluctuation of about 8 times as the ratio of the maximum value / minimum value. Further, the minimum value of 4 lx in the illuminance is equal to or lower than the reference minimum illuminance (for example, 5 lx) required for the normal road. On the other hand, as compared with this comparative example, the illuminance distribution of this example (FIG. 20A) is about twice as large as the ratio of the maximum value / minimum value as described above, and further the minimum illuminance is The value is also significantly higher than the reference minimum illuminance (for example, 5 lx), and it is understood that illumination with more uniform and sufficient illuminance is realized.

  Next, FIG. 22 (B1) shows a graph representing the illuminance distribution on the side surface 60s of the path 6 on the YZ plane in the comparative example (fluorescent lamp). According to the figure, it can be seen that the illuminance on the side surface 60s by the fluorescent lamp varies considerably in the longitudinal direction of the road (Y-axis direction) and also in the road height direction (Z-axis direction). On the other hand, as compared with this comparative example, it is understood that the LED lighting device 97 of this example (FIG. 21B) illuminates the side surface 60s with a more uniform illuminance as described above.

  Further, FIG. 22B2 shows the illuminance in the longitudinal direction (Y-axis direction) at a position on the side surface 60s of the path 6 and 1.5 m above the floor surface 60 in the comparative example (fluorescent lamp). The distribution and the illuminance distribution in the width direction (X-axis direction) at a position 1.5 m above the floor surface 60 are shown. Here, the position range of the illuminance distribution in the width direction includes a point directly under the fluorescent lamp. According to the figure, when the position is 1.5 m above the floor surface 60, the illuminance is greatly reduced to 3 lx at a position between the fluorescent lamp and the adjacent fluorescent lamp (position of ± 5 m). It does not satisfy the reference minimum illuminance (for example, 5 lx) required for the road. On the other hand, as compared with this comparative example, the LED lighting device 97 of the present example (FIG. 21A) is required to be at least a normal road even at a position 1.5 m above the floor surface 60 as described above. An illuminance of a reference minimum illuminance (for example, 5 lx) is secured, and illumination with a sufficient illuminance is realized. Note that, also in the graph of the illuminance distribution in the width direction in FIG. 22B2, both ends of the graph fall into positions where the illuminance is zero. This drop in the graph is also due to the convenience related to the setting of boundary conditions in the simulation. In practice, it should be noted that the illuminance in the width direction matches the illuminance in the longitudinal direction at a position on the side surface 60s.

  FIG. 23 is a graph that three-dimensionally displays the illuminance distribution on the floor surface 60 and the side surface 60s of the path 6 in the present example (LED lighting device 97) and the comparative example (fluorescent lamp).

  FIG. 23A shows a graph of this example. According to the figure, the illuminance distribution on the floor surface 60 and the side surface 60s of the road 6 is substantially uniform by the LED lighting devices 97 installed at equal intervals (every 10 m) on the ceiling of the road 6. It is understood that

  On the other hand, FIG. 23B shows a graph of a comparative example. According to the figure, the illuminance distribution on the floor surface 60 and the side surface 60 s of the road 6 by the fluorescent lamps 99 installed at equal intervals (every 10 m) on the ceiling of the road 6 is the installation interval of the fluorescent lamps 99. The light and darkness (illumination unevenness) corresponding to is clearly shown. Here, it is understood that the illuminance is greatly reduced at a position between the fluorescent lamp 99 and the adjacent fluorescent lamp 99.

  As described above, the LED lighting device 97 of the present invention can be used to illuminate the inside of the road 6 with a substantially uniform and sufficient illuminance. In particular, it is possible to illuminate the side surface 60s of the path 6 where the cable shelf 61 to be worked is installed with a substantially uniform and sufficient illuminance. Further, occurrence of color unevenness such as a yellow ring can be suppressed. As a result, a good working environment can be provided even in the road 6.

  Further, conventionally, there has been a problem that the illuminance in the intermediate region between the lighting devices of the path 6 becomes insufficient, but by using the LED lighting device 97 of the present invention, the illuminance having a sufficient magnitude in this intermediate region is also provided. Is secured and this problem is solved.

  Further, conventionally, there is a large difference between the maximum illuminance and the minimum illuminance in the road 6, and when the minimum illuminance is raised above the reference, the maximum illuminance becomes unnecessarily high, resulting in unnecessary power consumption. However, by using the LED lighting device 97 of the present invention, the ratio of the maximum illuminance to the minimum illuminance can be reduced to about twice, and the power consumption can be greatly suppressed.

  FIG. 24 is a cross-sectional view showing a modified embodiment of the LED lighting device 97.

  24 shows a cross section taken along the yz plane of the LED lighting device 97 ′, and corresponds to FIGS. 17D1, 17D2 and D3 in the LED lighting device 97. As shown in FIG. 24, the LED illumination device 97 ′ does not include the LED light source 12A for illumination directly below the LED illumination device 97, but instead has a reflective surface whose surface is a mirror surface. A portion 972R is provided.

  The reflecting portion 972R is attached to the lower end of the angle setting holder 972A, 972B, or 972C to which the LED lighting device 10A, 10B, or 10C is attached, and plays a role of supplementing the light flux by the omitted LED light source 12A. That is, the LED illumination device 10A, 10B, or 10C plays a role of reflecting and adding the return light emitted from the LED light source 12 and reflected by the uniformizing optical body 13 or the return light reflected by the cover to the irradiation light.

In addition, since the LED illumination device 97 ′ does not include the LED light source 12A that is a point light source, it does not have a bright spot even when the device is directly viewed from the outside, and is visually appealing and excellent in appearance. Furthermore, since the illumination directly under the apparatus can be supplemented by the reflecting portion 972R, sufficiently uniform illumination of the path 6 can be realized. In addition, in this change aspect, it is also preferable to provide the LED illumination device which has the optical axis directed directly below the apparatus, rather than the LED illumination device 10A (θ _10A = 50 °).

[Example of Todoroki Lighting: LED lighting device 98]

  FIG. 25 is a front view (FIG. 25 (A)) and a cross-sectional view (FIG. 25 (C)) showing an LED lighting device 98 as an embodiment of the present invention, and LED lighting devices 10D and 10E in the device 98. It is the schematic (FIG. 25 (B1)-(B4)) which shows orientation. FIG. 25C illustrates a cross section taken along the line L-L in FIG.

  According to FIG. 25 (A), the LED lighting device 98 is the same as the LED lighting device 97 (see FIG. It has the same configuration as 17).

  The LED lighting device 98 includes 12 LED lighting devices 10D and 4 LED lighting devices 10E, and includes device rows (groups) arranged in the order of 10E, 10D, 10D, 10D, 10D, 10D, 10D, and 10E. Includes two rows. These LED lighting devices 10D and 10E are installed in angle setting holders 982A and 982B, respectively, and are set to have different orientations and optical characteristics.

  Specifically, the LED lighting device 10D has the same optical characteristics as the LED lighting device 10B (FIGS. 19A1 to 19A3) as a long-distance optical system. On the other hand, the LED lighting device 10E has the same optical characteristics as the LED lighting device 10A (FIG. 19 (B1) and (B2)) as an intermediate distance optical system.

Further, according to FIGS. 25B1 to 25B4, the orientations of the LED lighting devices 10D and 10E, that is, the orientations of the optical axes _X10D and _X10E are set as follows.
LED lighting device 10D: θ _10D = 30 to 50 °
θ _SIDE1 = 15 to 40 ° (+ x direction)
LED lighting device 10E: θ _10E = 15 to 40 °
θ _SIDE2 = 15 to 40 ° (+ x direction)
Here, the orientations of the optical axes X _10D and X _10E shown in FIGS. 25B1 to 25B with respect to the xyz axis are those for the LED lighting devices 10D and 10E located on the lower right side in FIG. It should be noted that the optical axes X _10D and X _10E at other positions are appropriately changed as to which of the positive and negative sides of the xyz axis is directed.

  As described above, in the LED lighting device 98, the optical axes of the 16 LED lighting devices are not only tilted in the + z direction from the xy plane, but are also tilted in the ± x axis direction from the yz plane. Therefore, when the LED lighting device 98 is installed, for example, on the ceiling part of the road, these optical axes extend not only to the floor surface but also to the side surface of the road. Further, when the LED lighting device 98 is installed, for example, on the side surface (wall surface) of the shaft shaft portion of the roadway, these optical axes are not only directed to the side surface facing the side surface of the roadway but also adjacent to the side surface. It will also extend toward the side.

  According to FIG. 25C, the LED lighting device 98 includes an optically transparent cover 985 attached so as to cover the LED lighting devices 10D and 10E. In addition, a light diffusion sheet 988 is installed immediately inside the cover 985. In general, a light diffusion sheet is made of a copolymer of methyl methacrylate and vinyl benzoate, or a resin in which a large number of fine particles (beads) formed from silica or the like are dispersed inside, a film such as polyester or polyethylene terephthalate (PET). It coats on one side or both sides. Light is diffused at the interface of these beads and resin having different refractive indexes.

  In the LED illumination device 98, a light diffusion sheet 988 is installed at a position separated from the emission surfaces of the LED illumination devices 10D and 10E by 1 mm or more. By securing this distance, the diffusion effect of the emitted light by the light diffusion sheet 988 can be made effective.

In general, lighting in an environment where natural light is not inserted, such as a road,
(A) not only have sufficient illuminance to perform or pass the work,
(B) It is required to use irradiation light that is not dazzling for workers or passersby (does not interfere with work / passage). However, illumination using an LED light source appears to be a point light source for an operator or passer looking toward the light source even if the emitted light has a predetermined light distribution angle using an optical lens system. It will make you feel glare and give it “dazzle”. For these reasons, illumination using a fluorescent lamp that has a radiated light diffused and looks like a surface light source has been mainly employed on a road that is a work space and a passage.

  In contrast, in the LED lighting device 98, the combination of the LED lighting devices 10D and 10E and the light diffusing sheet 988 secures the illuminance required according to the illumination target and suppresses “dazzle”. Can be provided. Hereinafter, the operational effects of this exceptional combination will be described. First, “dazzle” will be considered.

  FIG. 26 is a graph showing the relationship between the angle formed by the line-of-sight direction with respect to the emitted light and the amount of luminous flux that feels “dazzle”, and a schematic diagram for explaining the action of the light diffusion sheet.

As an experiment for considering “glare”, the glare when the LED lighting device emitting light was viewed from various angles was measured. The measurement of the glare was performed as visual judgment of the same tester, that is, as a sensory test. Specifically, the tester increases the amount of current applied to the LED lighting device while looking at the LED lighting device having a predetermined optical characteristic emitted from a position 1 m away from the position with a line-of-sight angle θ _s. The total luminous flux at the time when the person judged “dazzling” was defined as “dazzling luminous flux threshold”.

In the graph of FIG. 26 (A), the horizontal axis is an angle between the optical axis and the visual axis of the LED lighting device gaze angle theta _{s (degree} (°)), the vertical axis, the line of sight angle theta _s " These are the “dazzling luminous flux threshold” (lm) and the applied current amount (mA) at that time.

According to FIG. 26 (A), there is a “dazzling luminous flux threshold” at which any gaze angle θ _s does not feel dazzling. Further, the “glare luminous flux threshold” increases as the line-of-sight angle θ _s increases. Incidentally, a similar experiment, towards LED lighting device for a smaller long-distance light distribution angle is "glare light flux threshold" is less than, i.e. more bright at the same line of sight angle theta _s, it has been confirmed . This is considered to be due to the fact that in the LED lighting device for long distances with a smaller light distribution angle, the peak value of illuminance is higher even if the total luminous flux is almost the same as that for short distances. From this, it is understood that the illuminance peak value strongly influences the glare.

From the above results, it is understood that glare can be suppressed by adjusting the installation angle of the LED lighting device (the sight angle θ _s for an assumed worker or passerby). Specifically, it is considered that the directions of the optical axes X _10D and X _10E of the LED lighting devices 10D and 10E are tilted as shown in FIGS. 25 (B1) to (B4) (or according to the figure). In this case, the angles θ _10D , θ _10E , θ _SIDE1, and θ _SIDE2 are set so that the line-of-sight angle θ _s corresponding to the “dazzling luminous flux threshold” at the set input current amount is sufficiently secured for the worker or the passerby. It is understood that glare can be sufficiently suppressed by adjusting.

However, when the installation angle of the device is set as shown in FIGS. _25B1 to _25B4 , for example, the illuminance at the illumination destination (for example, the side surface of the road) with illumination light inclined at angles θ _SIDE1 and θ _SIDE2 It has been found that there may be cases where there is an excessively high region. For example, in the case of a road, it is very preferable in terms of work that the cable shelf 61 (FIG. 16A) installed on the side surface becomes brighter. However, from the viewpoint of the illuminance design of the entire road and the reduction of power consumption, it is desirable that the illuminance distribution in the longitudinal direction on this side not only ensure sufficient illuminance but also be leveled as much as possible. It is. In order to solve the problem of leveling the illuminance distribution, the LED lighting device 98 (FIG. 25C) includes a light diffusion sheet 988.

  In this LED lighting device 98, as shown in FIGS. 26B and 26C, the emitted light from the LED lighting device 10D or 10E passes through the light diffusion sheet 988 and the cover 985 and propagates to the outside. To do. At this time, the diffusion mode changes depending on the haze value Hz of the light diffusion sheet 988.

Here, the haze value Hz is an index indicating the degree of cloudiness or turbidity in a light transmission target such as a sheet or film, and the smaller the value, the more transparent. The haze value Hz is generally expressed by the following formula (15) Hz (%) = Td / Tt × 100
Defined by Here, Td is the diffuse transmittance, and Tt is the total light transmittance.

  As shown in FIG. 26B, when the light diffusion sheet 988 having a small haze value Hz is used, the emitted light from the LED lighting device 10D or 10E is partially diffused by the light diffusion sheet 988. The orientation by the lens system (homogenizing optical body) in the device is maintained, and the light is concentrated and emitted in the direction along the optical axis. On the other hand, as shown in FIG. 26C, when a light diffusion sheet 988 having a large haze value Hz is used, a large amount of emitted light from the LED lighting device 10D or 10E is diffused by the light diffusion sheet 988. The orientation imparted by the inner lens system (homogenizing optical body) is lowered to approach diffused light. At this time, part of the diffused radiated light propagates and reflects toward the inside of the apparatus, and contributes to improvement of illuminance in the vicinity immediately below the apparatus.

  FIG. 27 is a graph showing the illuminance distribution of illumination by the LED illumination device 98 when the light diffusion sheet is used and when it is not used.

  Here, as an experimental condition for deriving the illuminance distribution of FIG. 27, the LED illumination device 98 is located at a height of 2 m, on the center line in the longitudinal direction on the illumination target surface assuming the floor surface of the road, A plurality were provided at intervals of 10 m, and the apparatus was installed so that the longitudinal direction of the apparatus was orthogonal to the longitudinal direction of the illumination target surface.

FIG. 27A shows the illuminance distribution for the longitudinal position Y on the center line of the illumination target surface (floor surface) when the light diffusion sheet 988 having a haze value of 89% is used and when it is not used. According to the figure, by using the light diffusing sheet 988 (Hz = 89%), the illuminance increases at a position directly below the LED lighting device 98, that is, a position directly facing the device 98 (Y = 0 and 10 m). On the other hand, the illuminance slightly decreases at an intermediate position (Y = 5 m) between the two LED illumination devices 98. this is,
(A) As shown in FIG. 26C, a part of the diffused radiation is propagated and reflected toward the inside of the apparatus, or (b) is far or laterally (for example, by the lens system) The emitted light oriented in the direction of the side of the road is returned to the vicinity of the device by the light diffusion sheet 988,
This is considered to contribute to illumination in the vicinity immediately below the device 98.

  Actually, when the light diffusion sheet 988 (Hz = 89%) is used, the average value of illuminance on the center line of the illumination target surface (floor surface) is 18.9 lx, and the light diffusion sheet 988 is not used. It is improved to about 1.4 times the average illuminance value (13.4 lx).

Next, FIG. 27B shows the illuminance distribution with respect to the longitudinal position Y on the center line of the illumination target surface (floor surface) when the light diffusion sheet 988 having a haze value of 86% is used and when not used. . Here, regarding the orientation of the optical axes X _10D and X _10E of the LED illumination device 10D or 10E in the LED illumination device 98 used in the experiment of FIG. 27, the LED illumination device used in the experiment of FIG. The angle is different from the orientation of the optical axes X _10D and X _10E at 98. Therefore, it should be noted that the illuminance absolute value cannot be compared between the graphs of FIGS. 27A and 27B.

  According to FIG. 27B, by using the light diffusing sheet 988 (Hz = 86%), the illuminance increases at the position (Y = 0 and 10 m) immediately below the LED lighting device 98, while the two LEDs Unlike the case of the light diffusion sheet 988 (Hz = 89%), the illuminance is generally maintained at the intermediate position (Y = 5 m) of the illumination device 98. Thus, by appropriately adjusting the haze value Hz of the light diffusing sheet 988, while increasing the illuminance directly under the apparatus, the illuminance substantially the same as when the light diffusing sheet 988 is not used even in the area between the apparatuses. The distribution can be maintained.

  Further, when the light diffusion sheet 988 (Hz = 86%) is used, the average illuminance on the center line of the illumination target surface (floor surface) is 20.1 lx, and the light diffusion sheet 988 is not used. It is improved to about 1.2 times the average illuminance value (16.7 lx).

  Next, in FIG. 27C, when the light diffusion sheet 988 having a haze value of 86% is used and when it is not used, the center line is parallel to the longitudinal center line of the illumination target surface (floor surface). The illuminance distribution at a point 1.5 m above a parallel line 1 m away from the width direction is shown. That is, the illuminance in the graph of FIG. 27C assumes illumination on the side of the road, and is illuminance at a height point of 1.5 m from the longitudinal position Y ′ on the parallel line. . Further, the LED lighting device 98 used in the figure is the same as the device used in FIG.

  According to FIG. 27C, by using the light diffusing sheet 988 (Hz = 86%), the illuminance is substantially maintained at the intermediate position (Y ′ = 5 m) between the two LED lighting devices 98 (substantially the same). On the other hand, at the position (Y ′ = 0 and 10 m) corresponding to the LED lighting device 98 in the position Y ′ direction, the illuminance decreases. As a result, it is understood that the illuminance distribution at a point of 1.5 m in height (corresponding to the position on the side of the road) is leveled to a considerable extent. This leveled illuminance generally indicates a value of 5 lx or more (for example, illuminance required for work) at any position Y ′.

  Here, the illuminance decreases at a position corresponding to the device 98 in the position Y ′ direction (Y = 0 and 10 m) because, for example, the radiated light oriented to the side surface side for illuminating the side surface is light diffused. It is considered that a part of the sheet 988 is collected in an intermediate region between the apparatuses by passing through the sheet 988. Note that the illuminance at the intermediate position (Y = 5 m) of the two devices 98 in FIGS. 27A and 27B is not reduced or maintained by the radiated light collected in the intermediate region. It is.

Next, as described above as an example,
<Combination of LED lighting devices 10D and 10E and light diffusion sheet 988>
In order to confirm the special effects of the illuminant, the illuminance distribution between the case where the homogenizing optical body (lens system) is installed and the case where it is not installed is compared, and the difference between the two is considered.

  FIG. 28A is a graph showing the illuminance distribution of illumination by the LED illumination device 98 when the uniformizing optical body (lens system) is installed and when the light diffusion sheet 988 is used and when it is not used. is there. FIG. 28B shows the illuminance distribution of illumination by the LED illumination device 98 when the uniformizing optical body (lens system) is not installed and when the light diffusion sheet 988 is used and when it is not used. It is a graph.

  In the graph of FIG. 28A, the illuminance value is normalized with the value when the lens system is installed and the light diffusion sheet 988 is not used being set to 1. In the graph of FIG. 28B, the illuminance value is standardized with a value of 1 when no lens system is installed and the light diffusion sheet 988 is not used. Furthermore, the illuminance distribution is a distribution with respect to the longitudinal position Y on the center line of the illumination target surface (floor surface). For the light diffusion sheet 988, three types of haze values Hz = 86%, 89% and 92% were used.

  According to FIG. 28A, which has a lens system, when there is a lens system and a light diffusion sheet (Hz = 86 to 92%), there is a lens system and no light diffusion sheet (standardized illuminance = 1). Compared with the case, the illuminance directly under the LED lighting device 98 is increased. In addition, with the lens system and the light diffusion sheet (Hz = 86%, 89%), the illuminance is with the lens system and no light diffusion sheet (standardized illuminance = 1) even if the lens 98 is separated from the position immediately below the device 98. Maintains roughly the same as the case. These results are similar to the results shown in FIGS. 27 (A) and (B).

  On the other hand, according to FIG. 28B, which has no lens system, when there is no lens system and there is a light diffusion sheet (Hz = 86 to 92%), there is no lens system and no light diffusion sheet (standardized illuminance = Compared with the case of 1), the illuminance is substantially equal or decreased in the entire longitudinal position Y. In particular, when the lens system is not used and the light diffusion sheet is used (Hz = 92%), the illuminance is significantly reduced.

  Here, the haze value Hz of the light diffusion sheet 988 to be used is preferably 90% (less than) as the upper limit from the results described above. On the other hand, with regard to the lower limit, it has been confirmed by experiments that a strong correlation exists between the haze value Hz and the spectral transmittance (%). When the haze value Hz is 70% or more, the spectral transmittance is reduced. I know it will be abrupt. Accordingly, the haze value Hz = 70% (or higher) at which the spectral transmittance starts to be influenced more strongly and the above-described operational effects of the present invention are easily exhibited can be set as the lower limit. That is, the haze value Hz is preferably set to a value of 70% or more and less than 90%. Further, since the result of the illuminance distribution in FIG. 27B is more preferable than the result of the illuminance distribution in FIG. 27A, the haze value Hz is set to a value of 70% or more and less than 87%. More preferably.

  From the results of FIGS. 28A and 28B described above, (a) increase in illuminance directly under the apparatus, and (b) in the presence of a lens system and light diffusion sheet (Hz = 86%, 89%). The extraordinary effects of maintaining the illuminance at a position separated from directly under the device and (c) improving the average illuminance as a result of these will not be successful if either the lens system or the light diffusion sheet is missing. It is understood that this is due to a bond.

  In addition, it is also preferable that the LED illuminating device 98 which exhibits these effects (a) to (c) is installed, for example, on the side surface (wall surface) of the shaft portion in the tunnel. In this case, after lighting not only the wall facing the wall where the device is installed, but also the adjacent wall, a good lighting environment is realized in which glare is suppressed for workers and passersby in the shaft It becomes possible.

  All the embodiments described above are illustrative of the present invention and are not intended to be limiting, and the present invention can be implemented in various other modifications and changes. Therefore, the scope of the present invention is defined only by the claims and their equivalents.

1, 7, 8, 9, 9 ′, 95, 96, 97, 97 ′, 98 LED lighting device 10, 10a, 10b, 10c, 10A, 10B, 10C, 10D, 10E LED lighting device 100, 101, 102, DESCRIPTION OF SYMBOLS 103 LED illumination device body 11 Base 110,110A, 110B, 110C Circuit board 12,12A LED light source 13 Homogenizing optical body 13A, 13B, 13C Homogenizing optical assembly 130 Light distribution angle control lens part 131 Microlens array part 15 Intensity distribution 16 Case 17 Lid 18, 73, 83, 93, 94 ′ Power supply line 19 Heat radiation part 20, 21 Emission light 200, 210, 300, 310, 331, 340, 350, 360, 380, 390, 400, 410 , 420 Illumination area 30, 31, 33, 34, 35, 36, 38, 38a, 38b, 39, 40, 41, 42 Irradiation light 330 Plane perpendicular to optical axis 5 Road (passage)
50 Road surface 6 Road 60 Floor surface 60s Side surface 61 Cable (/ tube) shelf 71, 81, 91, 91 ', 970 Housing 710, 711 Installation surface 72, 82, 92, 975, 985 Cover 74, 84, 94, 930 ', 931' Mounting screw 920 ', 921' Holding frame 940 ', 941' Seal member 971, 971 'Secondary battery 972A, 972B, 972C, 982A, 982B Angle setting holder 972R Reflector 973 Mounting support 974 Mother circuit Substrate 976 AC / DC converter 977 Cable 99 Fluorescent lamp 988 Light diffusion sheet

Claims (31)

An illumination method using an LED illumination device including a plurality of LED illumination devices,
The LED lighting device is:
A light source with a light emitting diode chip;
A light distribution angle control lens unit that receives the emitted light from the light source and controls the light distribution angle to a predetermined light distribution angle;
Including a plurality of microlenses arranged with the emission positions of the light distribution angle control lens section as lens arrangement surfaces, and a microlens array section that receives and disperses the emitted light whose light distribution angle is controlled,
The plurality of microlenses has a radius of curvature R, a pitch P that is a distance between lens vertices in adjacent microlenses, or both the radius of curvature R and the pitch P. An anisotropic microlens that differs between the direction of one axis and the direction of the axis perpendicular to the axis, and the pitch P differs between the directions of the axes connecting the lens vertices in the lens array plane. ,
The illumination method includes:
Combine the emitted light from the plurality of LED lighting devices to form an illumination light having an illumination region portion of a certain width,
An illumination method, wherein the illumination target surface is irradiated with the irradiation light. A plurality of the LED lighting devices are arranged side by side along the longitudinal direction of the illumination target surface at a position facing the illumination target surface,
2. The illumination method according to claim 1, wherein irradiation light from each of the plurality of LED illumination devices is arranged in the longitudinal direction while being adjacent to each other or partially overlapped to irradiate the illumination target surface. . The LED lighting apparatus includes a plurality of device groups including a plurality of the LED lighting devices,
The optical axis of one device group and the optical axis of the other device group are different from each other in the longitudinal vertical plane including the longitudinal axis and the normal line of the illumination target surface. The illumination method according to claim 2, wherein the illumination target surface is irradiated with the irradiation light from the other device group and the irradiation light from the other device group. The LED lighting apparatus includes a plurality of device groups including a plurality of the LED lighting devices,
Irradiation light from the one device group in a state in which the optical axis of one device group and the optical axis of the other device group have different directions in a cross section orthogonal to the longitudinal axis of the illumination target surface The illumination method according to claim 2, wherein the illumination target surface is irradiated with the irradiation light from the other device group.   The lighting method according to claim 3 or 4, wherein the plurality of LED lighting devices included in one device group form one row.   The plurality of LED lighting devices included in one device group and the plurality of LED lighting devices included in the other device group are alternately arranged or mixed to form one row. The illumination method according to claim 3 or 4, characterized in that   The one row has a direction in a longitudinal vertical plane including a longitudinal axis and a normal line of the illumination target surface, or a direction in a cross section perpendicular to the longitudinal axis of the illumination target surface. The illumination method according to 5 or 6. The plurality of LED illumination devices are installed at a predetermined interval above at least one end in the width direction of the illumination target surface,
In a state where the optical axis of the irradiation light from each of the plurality of LED illumination devices is inclined with respect to the normal line of the illumination target surface in a cross section orthogonal to the longitudinal axis of the illumination target surface, the irradiation light is The illumination method according to any one of claims 2 to 7, wherein the illumination target surface is irradiated.   The illumination method according to claim 8, wherein the width of the illumination shape in the width direction of the illumination target surface is substantially matched with the width of the illumination target surface. The height from the illumination target surface to the LED illumination device is h, the width of the illumination target surface is W, the irradiation angle of the irradiation light from the LED illumination device is α, and the optical axis of the irradiation light and the The angle θ _el formed by the normal of the surface to be illuminated is
W = h · tan (α / 2 + θ _el ) + h · tan (α / 2−θ _el )
The illumination method according to claim 9, wherein the illumination target surface is irradiated with irradiation light from a plurality of the LED illumination devices. The LED lighting apparatus includes a plurality of device groups including a plurality of the LED lighting devices,
The first device group illuminates the outer region of the region directly facing the device on the illumination target surface,
The second device group has an optical axis that forms a larger angle with respect to the normal of the illumination target surface as compared to the optical axis of the first device group, and The illumination method according to claim 1, wherein a further outer region is illuminated. The illumination target surface is a portion of an inner surface including a side surface in the passage,
A plurality of the LED lighting devices included in the third device group are respectively predetermined with respect to a surface defined by the optical axis of the first device group and the optical axis of the second device group. The illumination method according to claim 11, wherein the illumination method irradiates a region within a predetermined range on a side surface of the passage having an optical axis inclined at an angle. The illumination target surface is a portion of an inner surface including a side surface in the passage,
The LED lighting apparatus includes a plurality of device groups including a plurality of the LED lighting devices,
The plurality of LED lighting devices included in the plurality of device groups are defined by a longitudinal axis in the apparatus and an axis extending from the apparatus toward the region of the illumination target surface directly facing the apparatus. 12. The method according to claim 1, further comprising: irradiating a region within a predetermined range on a side surface of the passage having an optical axis inclined at a predetermined angle with respect to the surface to be formed. The illumination method according to item.   The LED illumination apparatus includes a light diffuser on the emission side of at least one of the LED illumination devices, and diffuses and emits light emitted from the at least one LED illumination device through the light diffuser. The lighting method according to claim 1, wherein the lighting method is performed.   The illumination method according to claim 14, wherein the illuminance in the region directly facing the device on the illumination target surface is increased by passing the emitted light through the light diffuser. A plurality of the LED lighting devices are installed side by side along the longitudinal direction of the illumination target surface,
After adjusting the haze value of the light diffuser in each LED illuminating device, the intermediate region between the regions directly facing the device on the illumination target surface by passing the emitted light through the light diffuser The illumination method according to claim 14, wherein the illuminance at is substantially equal to the illuminance when the light diffuser is not used.   The lighting method according to claim 15 or 16, wherein the haze value of the light diffuser is adjusted to a value of 70% or more and less than 90%. When the height from the illumination target surface to the LED illumination device is h, and the installation interval of the plurality of LED illumination devices is D, the irradiation angle β of the irradiation light from the LED illumination device is
β ≧ 2 · tan ⁻¹ (D / (2h))
11. The illumination method according to claim 2, wherein the illumination target surface is irradiated with irradiation light from a plurality of the LED illumination devices.   2. The illumination shape of the irradiation light having the illumination region portion having a certain width is a substantially rectangular shape or a substantially square shape in which an area ratio with respect to a circumscribed rectangle or square is 0.9 or more. The lighting method according to any one of 18 to 18.   2. The illumination according to claim 1, wherein the illumination target surface is irradiated with the irradiation light in a state where an optical axis of the illumination light from the LED illumination device is inclined with respect to a normal line of the illumination target surface. Method. An LED lighting device comprising a plurality of LED lighting devices,
The LED lighting device is:
A light source with a light emitting diode chip;
A light distribution angle control lens unit that receives the emitted light from the light source and controls the light distribution angle to a predetermined light distribution angle;
Including a plurality of microlenses arranged with the emission positions of the light distribution angle control lens section as lens arrangement surfaces, and a microlens array section that receives and disperses the emitted light whose light distribution angle is controlled,
The plurality of microlenses has a radius of curvature R, a pitch P that is a distance between lens vertices in adjacent microlenses, or both the radius of curvature R and the pitch P. An anisotropic microlens that differs between the direction of one axis and the direction of the axis perpendicular to the axis, and the pitch P differs between the directions of the axes connecting the lens vertices in the lens array plane. ,
A plurality of LED lighting devices are arranged such that emitted light from each of the plurality of LED lighting devices forms irradiation light having an illumination region portion having a constant width. A plurality of device groups including a plurality of the LED lighting devices;
The LED illumination apparatus according to claim 21, wherein the optical axis of one device group and the optical axis of another device group have different directions.   The LED lighting device according to claim 22, wherein a plurality of the LED lighting devices included in one device group form one row.   The plurality of LED lighting devices included in one device group and the plurality of LED lighting devices included in another device group are alternately arranged or mixed to form one row. The LED illumination device according to claim 22.   A plurality of the LED lighting devices included in one device group and a plurality of the LED lighting devices included in another device group have a predetermined angle with respect to each other of an emission surface of less than 180 degrees or more than 180 degrees. The LED lighting device according to any one of claims 22 to 24, wherein the LED lighting device is arranged so as to be formed.   26. The light distribution angle control lens unit and the micro lens array unit in a plurality of the LED lighting devices included in one device group are integrally formed. The LED lighting device according to item 1. The first device group is installed so as to illuminate an outer region of a region directly facing the device on the illumination target surface,
The second device group has an optical axis that forms a larger angle with respect to the direction toward the region that directly faces the device, as compared to the optical axis of the first device group, 27. The LED lighting device according to any one of claims 22 to 26, wherein the LED lighting device is installed so as to illuminate a further outer region of the outer region. A plurality of the LED lighting devices included in the third device group are predetermined with respect to a surface defined by the optical axis of the first device group and the optical axis of the second device group. 28. The LED lighting device according to claim 27, wherein the LED lighting device has an optical axis inclined at an angle.   The plurality of LED lighting devices included in the plurality of device groups are defined by a longitudinal axis in the apparatus and an axis extending from the apparatus toward a region directly facing the apparatus on the illumination target surface. The LED illumination device according to any one of claims 22 to 27, wherein each of the LED illumination devices has an optical axis that is inclined at a predetermined angle with respect to the surface.   A light diffuser is provided on the emission side of the at least one LED lighting device, and further includes a light diffuser for diffusing and irradiating the emitted light from the at least one LED lighting device. Item 30. The LED illumination device according to any one of Items 22 to 29.   The LED lighting device according to claim 30, wherein the light diffuser has a haze value of 70% or more and less than 90%.