JP2005285697A - Lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact lighting system having very high illuminance and uniform light distribution characteristics and being manufacturable comparatively at low cost. <P>SOLUTION: A lamp 10 for reading is provided with an electrical wiring board 15 on which a connector 15a for power supply is formed, a plurality of LED chips 11 mounted on the electrical wiring board 15 in a predetermined arrangement pattern, a deflection lens array 13 which is arranged among the LED chips 11 and a predetermined illumination region Z, while being close to these LED chips 11 and in which a plurality of deflection lenses 17 for leading light emitted from the LED chips 11 into the predetermined illumination region Z, while the light is in a state of being mutually overlapped are integrally formed, and a housing 14 storing these deflection lens array 13 and electrical wiring board 15. The light emitted from the LED chips 11 is collected, in a state of all of the light being superimposed in the common and single illuminating region Z via the deflection lenses 17. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a compact lighting device having high illuminance and uniform light distribution characteristics.

  Light-emitting diodes (LEDs) that are compact, consume less power, and have a lifespan more than ten times that of fluorescent lamps, etc., incorporate a condensing lens that allows light emitted without the addition of special reflectors. About 90% can be emitted forward, and high-luminance light with extremely strong directivity can be emitted. In addition, large LEDs (power LEDs) that have a larger light-emitting area than conventional ones and have significantly higher luminance have been developed. Therefore, low power consumption and compact illumination light sources that replace conventional incandescent and fluorescent lamps have been developed. As such, application is considered in various fields.

  Techniques relating to LEDs that can be used as such illumination light sources have been proposed in Patent Documents 1 to 3 and the like. Patent Document 1 discloses a semiconductor light emitting device that uses a selected light emitting diode element and avoids characteristic deterioration / characteristic defect due to bonding of thin lead wires so that there is no variation in characteristics and reliability can be increased. A module is disclosed. Patent Document 2 discloses a planar semiconductor light emitting element in which collimating optical elements having an arrangement corresponding to the arrangement of LED chips are arranged as a microlens array, and most of the light emitted from each LED chip is disclosed. Can be emitted in a very narrow range. Further, Patent Document 3 discloses a semiconductor light emitting module in which an outer lens facing each of the light emitting diodes arranged at a predetermined interval is arranged so that a wide area can be illuminated.

JP-A-9-69651 JP 2002-49326 A Japanese Patent No. 3118798

  A power LED with a larger light emitting area than a conventional LED has a relatively large variation in light emission brightness from product to product, and in order to obtain a product with a light emission brightness that falls within a predetermined tolerance, its production yield is the current technology. There are only tens of percent. Therefore, when this is adopted as a light source for illumination that requires uniform light distribution characteristics, there is a drawback that it becomes extremely expensive due to the low manufacturing yield described above.

  In the semiconductor light emitting module disclosed in Patent Document 1, light emitting diode elements are selected in order to avoid variation in characteristics. For this reason, as a result of basically eliminating the use of light emitting diode elements that do not fall within a predetermined tolerance, as in the case of power LEDs, the yield of the manufactured light emitting diodes deteriorates and the manufacturing cost of the semiconductor light emitting module is reduced. It has the disadvantage of becoming bulky.

  In the planar semiconductor light emitting element disclosed in Patent Document 2, collimating optical elements having an arrangement corresponding to the arrangement of the LED chips are arranged as a microlens array, and therefore, according to variations in emission luminance of individual LED chips. There is a disadvantage that uneven illumination occurs. In addition, since an LED chip array having an area corresponding to the illumination area is required, when illuminating a wide area with uniform light distribution characteristics, it is necessary to use a large number of LED chips corresponding to this, and the cost is reduced. It is hardly practical in terms.

  As is clear from the fact that the light emitting diode and the outer lens are coaxially arranged in the semiconductor light emitting module disclosed in Patent Document 3, each light emitting diode and the outer lens divide only a part of the entire illumination area. It comes to illuminate. For this reason, as in the case of Patent Document 2, the variation in the light emission luminance of each light emitting diode becomes the illuminance unevenness of the illumination region as it is, and it is basically impossible to obtain a uniform light distribution characteristic, that is, an illuminance distribution. In addition, when light emitting diodes are selected in order to avoid such problems, there is a drawback that the manufacturing cost increases.

  An illumination device according to the present invention includes a wiring board on which a connection to a power source is formed, a plurality of semiconductor light emitting elements mounted on the wiring board in a predetermined arrangement pattern, and the semiconductor light emitting elements in proximity to the semiconductor light emitting elements. An optical deflection optical system disposed between the semiconductor light emitting element and the predetermined spatial region, and guiding the light emitted from the semiconductor light emitting element to the predetermined spatial region in a state of being superimposed on each other, and the optical deflection optical system And a housing for housing the wiring board.

  In FIG. 1 showing the principle of the present invention, light L emitted from each semiconductor light emitting element 1 is guided in a state of being superimposed on a predetermined space region Z via a light deflection optical system 2. In other words, the light emitted from each semiconductor light emitting element 1 is collected in a state where all the light is superimposed on the single space region Z.

  In the lighting device according to the present invention, at least two types of semiconductor light emitting elements having different color rendering properties can be mixedly mounted on the wiring board at a predetermined ratio.

  A filter through which light emitted from at least one semiconductor light emitting element passes can be disposed between the semiconductor light emitting element and the light deflection optical system, or between the light deflection optical system and a predetermined spatial region. In this case, the filter may be a color filter for adjusting color rendering or a neutral filter having a distribution in the amount of transmitted light.

  The semiconductor light emitting element may be an LED in which a condensing lens is integrated, particularly a white LED, and the optical axes of these LEDs may be set parallel to each other.

  The predetermined spatial region in the present invention may be a two-dimensional plane intersecting or parallel to the optical axis of the LED, or may be a three-dimensional solid surface. When the predetermined spatial region is a three-dimensional solid surface, a hologram is suitable as the light deflection optical system.

  The light deflection optical system has a plurality of plano-convex lenses corresponding to individual semiconductor light-emitting elements. These plano-convex lenses are a flat optical surface facing the semiconductor light-emitting element side and a convex optical surface facing the predetermined space region side. And the flat optical surfaces of the individual plano-convex lenses may all be on a common plane.

  In this case, the convex optical surfaces of the individual plano-convex lenses can be formed as asymmetric aspheric surfaces, and the optical axes of these plano-convex lenses can be tilted toward the predetermined spatial region side.

  Alternatively, the optical axis of the LED and the optical axis of the corresponding plano-convex lens are set in parallel, the plano-convex lens array pattern is set to be similar to the semiconductor light-emitting element array pattern, and the spacing between adjacent plano-convex lenses Can be set shorter than the interval between adjacent semiconductor light emitting elements.

  It is effective to integrally form a plurality of plano-convex lenses in an array.

  According to the lighting device of the present invention, a plurality of semiconductor light emitting elements mounted in a predetermined arrangement pattern on a wiring board on which a connection portion for a power source is formed, and the semiconductor light emitting elements in proximity to these semiconductor light emitting elements. All the semiconductor light emitting elements are provided with a light deflection optical system that is arranged between the predetermined spatial areas and guides the light emitted from the semiconductor light emitting elements to the predetermined spatial areas in a state of being superimposed on each other. Since the light from each other is guided to the same place so as to overlap each other, it is possible to illuminate a predetermined spatial region with extremely high luminance. Further, even if there is uneven brightness of the individual semiconductor light emitting elements themselves, since all the light is guided to the same location, the influence of uneven brightness of the individual semiconductor light emitting elements themselves does not occur at all. For this reason, it is possible to use a plurality of semiconductor light emitting elements having a large variation in luminance without sorting, and particularly, it is possible to effectively use a power LED having a low manufacturing yield. Even if one of the plurality of semiconductor light emitting elements does not emit light for some reason, the illuminance of the illumination area only decreases by that amount, and the lighting device cannot be replaced. Very convenient.

  Further, since a plurality of semiconductor light emitting elements are mounted on the wiring board, it becomes possible to modularize the plurality of semiconductor light emitting elements mounted on the wiring board, and according to the illuminance required for the illumination area. By increasing or decreasing the number of modules, the illuminance of the lighting device can be easily changed.

  When at least two types of semiconductor light emitting elements having different color rendering properties are mixedly mounted on the wiring substrate at a predetermined ratio, illumination light having a desired color rendering property can be obtained. For this reason, for example, by only preparing two types of point semiconductor light emitting elements with color temperatures of 4800K and 7200K, by changing the combination of the numbers used, almost any color temperature between 4800K and 7200K is obtained. Illumination light can be obtained, and it is not necessary to use a point semiconductor light emitting element having a specific color rendering property.

  When a filter through which light emitted from at least one semiconductor light emitting element passes is provided, the color temperature of the illumination area can be finely corrected, or the illuminance distribution of the illumination area can be more uniformly corrected.

  When the semiconductor light emitting element is an LED in which a condensing lens is integrated, particularly a white LED, and when the optical axes of these LEDs are set parallel to each other, general white light can be obtained as illumination light. The LED mounting operation on the wiring board can be performed easily and quickly.

  When a hologram is used as the light deflection optical system, uniform illumination can be reliably performed even if the predetermined spatial region is a three-dimensional solid surface. In addition, the illumination device can be made more compact by setting the distance from the semiconductor light emitting element to the hologram to be the shortest.

  When the flat optical surfaces of the individual plano-convex lenses are all set on a common plane, it is possible to prevent the generation of shadows and bright lines due to the boundary portions of adjacent plano-convex lenses. In addition, this enables higher-density mounting of LEDs, and in combination with the ability to reduce the distance from the semiconductor light emitting element to the flat optical surface of each plano-convex lens, It can be made compact.

  When a plurality of plano-convex lenses are integrally formed in an array, the positioning of the plano-convex lens with respect to individual semiconductor light emitting elements becomes extremely easy, and the illumination device can be easily manufactured.

  Embodiments of the lighting device according to the present invention will be described in detail with reference to FIGS. 2 to 6, but the present invention is not limited to such embodiments, and the concept of the present invention described in the claims. Any changes and modifications included in the above are possible, and can naturally be applied to any other technique belonging to the spirit of the present invention.

  The external appearance of an embodiment in which the present invention is applied as a reading lamp incorporated in a learning desk is shown in FIG. 2, its cross-sectional structure is shown in FIG. 3, and the external appearance of the main part is shown in an exploded state in FIG. That is, the reading lamp 10 in the present embodiment is intended to illuminate the top of the deck T by being attached to the back surface of the shelf board S of the writing desk D, and the plurality of LED chips 11 have a predetermined arrangement pattern. The incorporated LED module 12, a deflection lens array 13 that is arranged in proximity to the front of the LED module 12 and irradiates light from the LED module 12 toward the surface of the deck T, and the LED module 12 and the deflection lens The main part is composed of a housing 14 that accommodates the array 13 in a positioned state.

  The LED module 12 includes a plurality of LED chips 11 each integrally incorporating a condenser lens 11a so that these optical axes 11b are parallel to each other, and an electric wiring board on which the LED chips 11 are mounted at a predetermined interval. 15 and a cable 16 for supplying power to the individual LED chips 11, etc., connected to each other via a connector 15 a provided on the electric wiring board 15. The LED chip 11 used as the semiconductor light emitting device of the present invention is a white power LED, and as a heat dissipation measure, the base of the electric wiring board 15 and the housing 14 are formed of aluminum having a relatively high thermal conductivity. In this embodiment, 17 LED chips 11 are arranged in two rows on the electric wiring board 15 and mounted in a state shifted by a half pitch along these directions, but the LED chips for the electric wiring board 15 are mounted. It goes without saying that the arrangement state of 11 can be appropriately changed according to the characteristics required for the illumination device.

  If a special lighting effect is not intended for an object to be illuminated, it is common to use a white LED having a color rendering property similar to sunlight as in the present embodiment. When a desired color rendering property cannot be obtained with only a single type of white LED, at least two types of white LEDs having different color rendering properties were combined and adjusted to the desired color rendering property using color subtraction mixing. Illumination light can be obtained. For example, when trying to obtain illumination light having a color temperature of 5600K, for example, by adopting a white LED having a color temperature of 7200K on the market and a white LED having a color temperature of 4800K in a ratio of 1: 2, Illumination light having a color temperature close to 5600K can be obtained. That is, according to this method, it is not necessary to manufacture a white LED having a color temperature of 5600K, and it is possible to effectively use a commercially available one.

  Since the locus of the color temperature on the chromaticity coordinates is not a straight line but a curved line, the color temperature linear interpolation as described above is possible in a limited area (for example, a range of 4800K to 7200K). When an LED having a color temperature outside this range is used, it is necessary to adjust the LED combination ratio based on the color temperature curve.

  The deflection lens array 13 in the present embodiment, which is arranged in a close proximity to the LED module 12 by a predetermined distance, is a molded product of optically transparent acrylic resin (PMMA), and corresponds to each LED chip 11. It has a deflecting lens 17 (plano-convex lens in this embodiment) set in a similar reduced arrangement pattern. Each deflection lens 17 has a flat optical surface 17a facing the LED chip 11 side and a convex optical surface 17b facing the illumination region Z, that is, the deck T side. Are set in parallel with the optical axis 11b of the condensing lens 11a, but since these are set in a similar reduced arrangement pattern corresponding to the LED chip 11, the interval between the adjacent deflection lenses 17 is adjacent. The state is set to be shorter than the interval between the condenser lenses 11a, and the optical axis 17c of the corresponding deflection lens 17 is offset to the center side of the illumination area Z with respect to the optical axis 11b of the condenser lens 11a. Yes. The offset amount of each deflecting lens 17 is set depending on the focal length and the relative positional relationship between the corresponding LED chip 11 and the illumination area Z.

  In the present embodiment, the flat optical surface 17a facing the LED chip 11 side is all positioned on a common plane so as to be substantially orthogonal to the optical axis 11b of the condenser lens 11a. This facilitates the manufacture of a mold for injection-molding the deflection lens array 13 and eliminates vignetting caused by a step at the boundary portion between adjacent deflection lenses 17 so that dark lines, bright lines, etc. are formed in the illumination area Z. Can be prevented, and further high-density mounting of the LED chip 11 can be enabled. Moreover, combined with the fact that the distance between the condenser lens 11a and the deflecting lens array 13 can be shortened to the shortest, the lighting device can be further downsized.

  The function required for the deflecting lens 17 is to guide the light beam emitted from the condenser lens 11a of each LED chip 11 to the single illumination area Z in an enlarged state with the illuminance distribution as uniform as possible. In other words, each deflection lens 17 is designed so that the image of the end face of the condenser lens 11a forms an image in a magnified state on the single illumination area Z, in this embodiment the surface of the deck T. For this purpose, the offset amount of each deflection lens 17 is set based on the relative position between the corresponding LED chip 11 and the illumination area Z. In addition, the convex optical surface 17b of each deflecting lens 17 is not limited to a spherical surface and is suitable for non-spherical surfaces, in addition to the condensing lens 11a incorporated in the LED chip 11, so that the illuminance distribution of light in the illumination area Z is uniform. It is effective to form a spherical shape.

  In addition, by offsetting the optical axis 17c of the corresponding deflection lens 17 to the center side of the illumination area Z with respect to the optical axis 11b of the condenser lens 11a, the illuminance distribution of the light reaching the illumination area Z is changed. It becomes non-uniform along the offset direction, and the illuminance on one end side (the optical axis 11b side of the corresponding condensing lens 11a) along the offset direction becomes relatively high, but the optical axes 17c of all the deflection lenses 17 By setting the offset direction to be symmetric with respect to the center of the LED module 12, all the non-uniformities in the illuminance distribution are offset, and as a result, the illuminance distribution in the illumination area Z can be kept substantially uniform.

  In this way, since all the light from the individual LED chips 11 is collected in a single illumination area Z, the surface of the deck T can be illuminated with extremely high illuminance, and the individual LED chips can be illuminated. Even if these emission luminances are non-uniform due to the manufacturing variation of 11, the illuminance unevenness as in the conventional illumination device can be completely eliminated. For this reason, the LED chip 11 which has been discarded as a defective product due to lack of luminance or the like can be used without any problem, and the component cost for the semiconductor light emitting element can be greatly reduced. Moreover, even when one LED chip 11 stops emitting light for some reason, the illuminance of the illumination area Z is only reduced by that amount, and can continue to be illuminated as long as there is no special reason.

  On the surface of the deflection lens array 13 facing the LED module 12 (on the flat optical surface 17a side), the LED module depends on the focal length of the deflection lens 17 and the size of the illumination area Z (magnification rate of the LED chip 11). A plurality of spacer pins 18 are formed in a protruding state from a region other than the flat optical surface 17a. Since it is necessary to change the design of the deflection lens 17 in accordance with the distance from the deflection lens array 13 to the illumination area Z (the surface of the deck T) and the size of the illumination area Z, the length of the spacer pin 18 also varies accordingly. It is necessary to change it at the same time. Since it is important to set the distance between the LED module 12 and the deflecting lens array 13 as designed, they are integrated using some fastening means so that their relative positions are not changed by an external force or the like. It is also effective to assemble it.

  The housing 14 is fitted into a main body 14a having a cup-shaped cross section corresponding to the contour shapes of the LED module 12 and the deflecting lens array 13, and an open end of the main body 14a, and is integrally connected by a set screw or the like (not shown). Cover portion 14b. The deflecting lens array 13 has both end edges in the arrangement direction abutting against the cover portion 14b so that the deflecting lens array 13 cannot be detached from the housing 14. Further, the deflecting lens array 13 is more securely attached to the housing 14 by some locking means. It can also be fixed inside. A hole 19 for guiding the cable 16 to the outside of the housing 14 is formed in the main body 14a, and the cable 16 drawn out of the housing 14 from here is supplied with power (not shown) via an on / off switch or dimming switch (not shown). Connected to cable. The LED module 12 is designed so that the back surface of the electric wiring board 15 is in contact with the bottom plate part 14c of the main body part 14a so that heat can be efficiently radiated to the housing 14 side. The structure of the housing 14 only needs to be able to securely fix the LED module 12 and the deflecting lens array 13 in the positioning state in the housing 14 and can be appropriately set in consideration of ease of assembly. is there.

  Therefore, when power is supplied to the LED module 12 via the cable 16, the illumination area Z on the surface of the deck T is illuminated with a uniform light distribution characteristic. The shape of the illumination area Z can be changed to a rectangle, an ellipse, or the like as necessary by changing the contour shape of each deflection lens 17.

  In the embodiment described above, the reading lamp 10 in which the illumination area Z is substantially orthogonal to the illumination light irradiation direction has been described. However, in the illumination device in which the illumination area Z is inclined with respect to the illumination light irradiation direction. The present invention can also be applied.

  FIG. 5 shows the appearance of another embodiment in which the lighting device according to the present invention is applied to a down-spotlight for wall lighting, and FIG. 6 shows the cross-sectional structure thereof. In this case, the same reference numerals are used, and duplicate explanations are omitted. That is, the down-spotlight 20 in the present embodiment is intended to illuminate an object O such as a picture or a photograph that is embedded in a ceiling R of a building and attached to a wall surface W such as a room or a hallway. An LED module 12 in which a plurality of LED chips 11 are incorporated, and the light deflection optics of the present invention that is arranged in front of the LED module 12 and irradiates light from the LED module 12 toward an object O fixed to the wall surface W. The hologram 21 as a system and the cylindrical housing 14 that houses the LED module 12 and the hologram 21 in a positioned state constitute a main part.

  An aluminum heat dissipating member 22 having heat dissipating fins 22 a is integrally joined to the electric wiring substrate 15 of the LED module 12, and the heat dissipating member 22 is attached to the housing 14 via a bracket 23 provided on the inner wall of the housing 14. It is in a fixed state. In the present embodiment, nine LED chips 11 are arranged in a grid pattern at the same pitch on the electric wiring board 15, but the illumination direction is inclined with respect to the optical axis 11 b of the condenser lens 11 a of the LED chip 11. Therefore, the LED module 12 is housed in an offset state with respect to the housing 14 so that vignetting by the housing 14 does not occur.

  The hologram 21 in the present embodiment, which is held in the main body portion 14a of the housing 14 by the cover portion 14b, is a molded product of optically transparent acrylic resin (PMMA). It has the effect | action which guides the light from the chip | tip 11 to the same illumination area | region Z in an enlarged state. In other words, the hologram 21 has a function almost similar to that of the projection lens 24 as shown by a two-dot chain line in FIG. 6 in which the optical axis (not shown) is inclined toward the center of the illumination area Z.

  Instead of the hologram 21 as in the present embodiment, it is possible to use a deflection lens array as in the previous embodiment, but the optical surface facing the LED chip 11 side of each deflection lens is the optical axis of the condenser lens 11a. All can be located on a common plane so as to be substantially orthogonal to 11b. It is also possible to incline the optical axis of each deflection lens toward the center side of the illumination area Z. In this case, the convex optical surface facing the illumination area Z side of the deflection lens is set to an aspherical surface. There is a need.

  In this embodiment, a filter 25 for adjusting color temperature is disposed between the LED module 12 and the hologram 21 so as to overlap the hologram 21, and for example, light from any one LED chip 11 is guided. Only the areas are colored in a predetermined color, and the other areas are completely colorless and transparent. As a result, the color temperature of the illumination area Z can be adjusted to a subtle degree that cannot be corrected by the combination of the commercially available LED chips 11 alone. Of course, it is also possible to use a filter in which an arbitrary region is colored in a plurality of different colors as necessary.

  In the above-described embodiment, the reading lamp 10 incorporated in the writing desk D and the down spotlight 20 embedded in the ceiling R of the building have been described. However, the present invention is not limited to such an illumination device, and is conventionally provided. As a general lighting device to replace incandescent lamps and fluorescent lamps, for example, an arm light attached to the tip of a movable arm having a plurality of joints, or taking advantage of high brightness, a stage lighting device, In addition to outdoor spotlights that attach to the ground etc. to illuminate wall surfaces of buildings, etc., lighting devices that need to be installed in places where replacement or maintenance is difficult by taking advantage of the long life of LEDs, For example, it can be used for a foot lamp incorporated in a bed in a hotel or the like.

  When the present invention is applied to an arm light, it is necessary to be able to exchange the light deflection optical system according to the distance between the illumination area and the semiconductor light emitting element and to change the interval between the semiconductor light emitting element and the light deflection optical system. It goes without saying that there is.

It is a principle diagram of the present invention. It is the stereographic projection figure showing the external appearance of one Embodiment which applied the illuminating device by this invention to the reading lamp integrated in a writing desk. It is sectional drawing of the principal part of embodiment shown in FIG. It is a three-dimensional projection figure showing the external appearance of embodiment shown in FIG. 2 in the decomposition | disassembly state. It is a three-dimensional projection figure showing the utilization condition of other embodiment which applied the illuminating device by this invention to the down spotlight. It is sectional drawing of embodiment shown in FIG.

Explanation of symbols

D Writing desk F Floor surface O Object R Ceiling S Shelf plate T Deck W Wall surface Z Illumination area 10 Reading light 11 LED chip 11a Condensing lens 11b Optical axis 12 LED module 13 Deflection lens array 14 Housing 14a Body portion 14b Cover portion 14c Bottom plate Portion 15 Electrical Wiring Board 15a Connector 16 Cable 17 Deflection Lens 17a Flat Optical Surface 17b Convex Optical Surface 17c Optical Axis 18 Spacer Pin 20 Down Spot Light 21 Hologram 22 Heat Dissipation Member 22a Heat Dissipation Fin 23 Bracket 24 Projection Lens 25 Filter

Claims (7)

A wiring board on which a connection to the power source is formed;
A plurality of semiconductor light emitting elements mounted in a predetermined arrangement pattern on the wiring board;
Light deflection that is disposed between the semiconductor light emitting element and a predetermined space region in a state adjacent to the semiconductor light emitting elements, and guides the light emitted from the semiconductor light emitting element to the predetermined space region in a state of being superimposed on each other. Optical system,
An illumination device comprising: the light deflection optical system; and a housing for housing the wiring board.   The lighting device according to claim 1, wherein at least two types of semiconductor light emitting elements having different color rendering properties are mixedly mounted on the wiring board at a predetermined ratio.   The illumination device according to claim 1, further comprising a filter through which light emitted from at least one of the semiconductor light emitting elements passes.   The said semiconductor light emitting element is LED which integrated the condensing lens integrally, The optical axis of these LED is set mutually parallel, The one in any one of Claims 1-3 characterized by the above-mentioned. Lighting device.   The illumination device according to claim 1, wherein the light deflection optical system is a hologram.   The light deflection optical system has a plurality of plano-convex lenses corresponding to the individual semiconductor light-emitting elements, and these plano-convex lenses are formed on a flat optical surface facing the semiconductor light-emitting element side and on the predetermined space region side. 5. The lighting device according to claim 1, wherein the flat optical surfaces of the individual plano-convex lenses are all on a common plane. The lighting device according to claim 6, wherein the plurality of plano-convex lenses are integrally formed in an array.

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