JP5689981B2 - Illumination device, backlight, and liquid crystal display device - Google Patents

Description

  The present invention relates to an illumination device using an LED as a light source, a backlight using the illumination device, and a liquid crystal display device.

  In recent years, light emitting diodes (LEDs) are often used as light sources for lighting devices. The LED has many advantages such as small size, long life, low power consumption due to high luminous efficiency, and no use of mercury, compared to fluorescent lamps (cold cathode tubes, etc.) that have been used conventionally. Yes.

  For example, the lighting device is attached to the ceiling of a living room and used as indoor lighting, or disposed on the back surface of a liquid crystal display device and used as a backlight. Since the LED is a point light source, a luminance distribution is formed in the light emitted from the light emitting surface, and uneven luminance tends to occur. Therefore, in order to suppress luminance unevenness caused by the fact that the LED is a point light source, a reflecting member is disposed on the surface facing the light emitting surface, and the light emitting surface and / or the surface of the reflecting member is aligned. An illuminating device in which LEDs are arranged to emit light in a direction has been proposed.

  In the illuminating device, since the light irradiation direction of the LED and the light emitting surface of the illuminating device intersect, the light flux density on the light emitting surface changes depending on the distance from the LED. When the luminous flux density changes in this way, the light emitted from the light exit surface is visually recognized as light with uneven brightness. In such an illuminating device, it is known that the luminous flux on the light exit surface can be made uniform or substantially uniform by narrowing the irradiation angle of the light emitted from the LED, and a method of attaching a collimator lens to the LED is proposed. (See, for example, JP 2009-205968 A).

  Such an illumination device will be described with reference to the drawings. FIG. 16 is an exploded perspective view of a conventional lighting device. As illustrated in FIG. 16, the lighting device 9 includes a chassis 91, a cover member 94 disposed so as to cover the chassis 91, and a substrate 932 that is disposed between the chassis 91 and the cover member 94 and on which the LED 933 is mounted. And a collimator lens 95. In the illumination device 9, the cover member 94 is a light emission surface.

  As shown in FIG. 16, the chassis 91 has a rectangular shape, and the substrate 932 on which the LEDs 933 are mounted is disposed along the long side. A portion of the chassis 91 facing the cover member 94 is provided with a reflecting portion 911 in which a portion away from the LED 933 is warped toward the cover member 94. The light emitted from the LED 933 is directly emitted from the cover member 94 and is reflected by the reflecting portion 911 and emitted from the cover portion 94.

  In addition, since the collimator lens 95 is attached to the front surface of the LED 933, the diffusion angle of the light emitted from the LED 933 is narrowed (close to parallel light), and uneven brightness of the light emitted from the illumination device 9 is suppressed. ing.

JP 2009-205968 A

  The lighting device 9 as shown in FIG. 16 has a configuration in which the LEDs 933 are arranged in a straight line in a direction orthogonal to the thickness direction. That is, when the length (size) of the substrate 932 is determined, the number of LEDs 933 is also determined. In order to brighten the emitted light in the illumination device 9 as described above, a method of using high output LEDs or arranging LEDs 933 in the thickness direction and increasing the number of LEDs 933 can be considered.

  However, when using a high-power LED, the amount of heat generated in a small region is high, and heat dissipation measures are required to suppress damage to the LED, collimator lens, and the like due to heat. This complicates the configuration of the lighting device, and may be large and expensive.

  Further, when the LEDs 933 are arranged in the thickness direction, the apparent size of the light source is increased. Therefore, a collimator lens that matches the size of the light source is required, and it is difficult to reduce the thickness of the lighting device.

  Accordingly, the present invention provides an illuminating device that can emit light with high brightness and high uniformity without increasing the size and complexity of the device, and a backlight or a liquid crystal display device using such an illuminating device. With the goal.

  In order to achieve the above object, the present invention provides a housing having a reflective portion facing a light emitting surface, and LEDs arranged in a straight line in a first direction that is along the reflective portion. Is arranged so as to face the surface on which the LED is mounted on the substrate, and the light emitted from the LED is arranged in a plurality of stages in a second direction intersecting the first direction. A light collecting member for collecting light in the second direction, and attaching the substrate and the light collecting member to the housing so that light emitted from the LED follows the reflecting portion. Provided is an illuminating device, wherein a member includes a light collecting portion for collecting light emitted from the LED in the second direction for each array of the LEDs.

  According to this configuration, even when the LEDs are arranged in a plurality of stages, it is possible to suppress an increase in a member that collects the light emitted from the LEDs. Thereby, since the freedom degree of the arrangement method of LED becomes high, it is possible to make the board | substrate with which said LED is mounted small. In addition, since the degree of freedom of the LED arrangement method is high, the number of LEDs to be mounted can be increased in the light emitting portion where the total luminous flux is the same. Thereby, since the calorific value of one LED becomes small, it can suppress that temperature becomes high in the narrow part on a board | substrate, and it is possible to omit the member for special exhaust heat etc.

  The said structure WHEREIN: The said condensing part may be a convex lens of the collimator shape formed in the surface on the opposite side to the surface facing the said LED. In addition, a different lens shape may be sufficient for every arrangement | sequence of said LED, and the same lens shape may be sufficient.

  The said structure WHEREIN: The surface facing the said LED of the said condensing member may incline with respect to the light emission surface of the said LED so that it may respond | correspond with each arrangement | sequence of the said LED. According to this configuration, since most of the light emitted from the LED can be directed to the light emitting surface, the light utilization efficiency is increased. In addition, as an example of the surface facing the LED, the inclination of the surface facing the LED of the light collecting member may be increased as the distance from the central portion in the second direction increases.

  In the above configuration, a concave lens surface having an inflection point in the vicinity of the front surface of the light emitting surface of the LED so that the surface of the light collecting member facing the LED corresponds to each of the LED arrays. Also good. After changing the direction of the light emitted from the LED with such a concave lens, the light is condensed by the light condensing unit, so that the focal length can be extended and the light can be condensed effectively. Examples of such a concave lens surface include a shape obtained by connecting two flat surfaces, and a curved surface shape such as an arc or an elliptical arc part line.

  In the illumination device having the above configuration, the substrate on which the LED is mounted and the light collecting member are attached to the outer surface side of the attachment portion formed in a polygonal cylindrical shape disposed in the central portion of the housing. It may be.

  In the illumination device having the above configuration, the housing includes a rectangular flat plate portion, and the substrate and the light collecting member are attached to a wall body protruding from at least one side of the flat plate portion. May be.

  Such an illuminating device can be used as a backlight of a back-lighting such as a light-emitting signboard or a back-lighted image display device such as a liquid crystal display device.

  ADVANTAGE OF THE INVENTION According to this invention, the illuminating device which can radiate | emit light with a high brightness | luminance and a high uniformity can be provided, without an apparatus becoming large-sized and complicated.

  In addition, by using the lighting device of the present invention, an increase in size and complexity of a backlight or a liquid crystal display device can be suppressed.

It is a disassembled perspective view of the illuminating device concerning this invention. It is the figure which looked at the light emission part used for the illuminating device shown in FIG. 1 from the side surface. It is the figure seen from the downward direction of the light emission part shown in FIG. It is the front view which expanded the flat plate part of the angle for attachment. It is sectional drawing cut | disconnected by the VV line | wire of the angle for attachment shown in FIG. It is the figure which expanded the board | substrate and the condensing member attached to the angle for attachment. It is a figure which shows the optical path of the light pierced from the light emission part of the conventional illuminating device. It is the light emission part of the illuminating device concerning this invention. It is a figure which shows the luminance distribution of the light radiate | emitted from the conventional illuminating device. It is a figure which shows the luminance distribution of the light radiate | emitted from the illuminating device concerning this invention. It is a figure which shows the luminance distribution along the diameter of the light radiate | emitted from the conventional illuminating device and the illuminating device of this invention. It is sectional drawing of the condensing member used for the other example of the illuminating device concerning this invention. It is sectional drawing of the condensing member used for the other example of the illuminating device concerning this invention. It is a figure which shows the irradiation direction of light when the surface which opposes LED is made into a plane, and when it is set as the lens surface which has an inflexion point in the vicinity of the light emission surface front. It is a disassembled perspective view which shows the other example of the illuminating device concerning this invention. It is a disassembled perspective view which shows an example of the liquid crystal display device concerning this invention. It is a disassembled perspective view of the conventional illuminating device.

  Embodiments of the present invention will be described below with reference to the drawings.

(First embodiment)
FIG. 1 is an exploded perspective view of a lighting device according to the present invention. A lighting device A shown in FIG. 1 is a ceiling light attached to a ceiling surface, and an upper portion in the drawing is attached to the ceiling surface. In the following description, when explaining the vertical direction, the vertical direction in the state of FIG. 1 will be described as a reference except when otherwise described, and the vertical direction in the state of FIG. (Vertical direction) or the thickness direction and lateral direction of the lighting device may be described as the H direction (horizontal direction).

  As shown in FIG. 1, the illuminating device A is provided with the chassis 1, the drive control part 2, the light emission part 3, and the cover 4, and is arrange | positioned in this order from the top. The chassis 1 is a casing attached to the ceiling surface, and is a disk-shaped member made of aluminum. A power connector (not shown) that is provided on the ceiling surface and supplies power passes through the central portion of the chassis 1. A surface opposite to the surface facing the ceiling surface of the chassis 1 is formed as a reflecting surface (reflecting portion) that efficiently reflects the light emitted from the light emitting portion 3 and is subjected to surface treatment. In addition, as this surface treatment, for example, a method of attaching a highly reflective sheet such as foamed PET or a white paint may be applied.

  The drive control unit 2 includes circuits such as a power supply circuit that supplies power to the light emitting unit 3 and a control circuit that performs lighting control. When the drive control unit 2 is attached to the chassis 1, the insulating sheet 20 for suppressing leakage to the chassis 1, a circuit board 21 on which a power supply circuit, a control circuit, and the like are mounted, and a support unit that supports the circuit board 21 22 and 23. The drive control unit 2 also includes a circuit that is electrically connected to a power connector (not shown) provided on the ceiling surface and converts the supplied power into power corresponding to the light emitting unit 3.

  The light emitting unit 3 is fixed to the chassis 1 with screws, and the drive control unit 2 is fixed to the light emitting unit 3 with screws. In a state where the drive control unit 2 and the light emitting unit 3 are attached to the chassis 1, the cover 4 is attached so as to surround the side of the chassis 1 where the drive control unit 2 and the light emitting unit 3 are attached. The cover 4 is fixed by engaging the outer peripheral portion with the chassis 1 and screwing the central portion to the light emitting unit 3. The cover 4 is a light exit surface from which light emitted from the light emitting unit 3 is emitted, and is made of a light resin with high transmittance such as acrylic resin such as PMMA, polystyrene, polycarbonate, etc., but is not limited thereto. . The cover 4 may be a surface processed so that emitted light is diffused.

  The light emitting unit 3 includes an attachment angle 31, a substrate 32 that is fixed to the attachment angle 31 and on which an LED 33 (described later) as a light source is mounted, and a light collecting member 5 that is disposed so as to cover the substrate 32. ing. In addition, it can be said that the light source part is comprised with the board | substrate 32 with which LED33 was mounted, and the condensing member 5. FIG. The light emitting unit 3 will be described with reference to a new drawing. 2 is a view of a light emitting unit used in the illumination device shown in FIG. 1 as viewed from the side, and FIG. 3 is a view of the light emitting unit as viewed from below in FIG.

  The mounting angle 31 of the light emitting unit 3 is formed by cutting and bending a metal plate. As shown in FIG. 1 and the like, the mounting angle 31 includes a rectangular flat plate portion 311, a plate-like fixing portion 312 extending from one long side of the flat plate portion 311, and a flat plate from the other long side of the flat plate portion 311. A holding portion 313 extending to the opposite side to the fixing portion 312 with respect to the portion 311 is provided.

  The mounting angle 31 is formed in a regular octagonal cylindrical shape by connecting the short sides of the adjacent flat plate portions 311 together. As described above, when the flat plate portion 311 is connected in a regular octagonal cylindrical shape, the fixing portion 312 extends toward the outside of the regular octagon, and the holding portion 313 extends toward the inside of the regular octagon. Moreover, although the regular octagonal thing is shown in the illuminating device A, it is not limited to this. It may be a shape that can hold a flat substrate in a cylindrical shape, and may be a shape close to a circle (for example, a regular hexagon, a regular dodecagon, etc.).

  Further, as shown in FIG. 1, the mounting angle 31 is divided into two members so that four flat plate portions 311 are included. Then, the divided members are manufactured by pressing metal plates one by one, and then joined to form a regular octagonal cylindrical shape. In addition, in the illuminating device A of FIG. 1, although the angle 31 for attachment is divided | segmented into two members, it is not limited to it, You may divide | segment into three or more, but the divided member is The number of divisions having the same shape (for example, 2, 4, and 8 in the case of a regular octagon) is preferable. In addition, by making the divided | segmented member into the same shape, the shape of the metal plate of material and the metal mold | die for press work can be unified, and manufacturing cost can be reduced.

  As shown in FIGS. 2 and 3, the substrate 32 is arranged so that the LED 33 is on the outer side of the regular octagonal cylindrical shape on the flat plate portion 311 of the mounting angle 31, and the longitudinal direction is the H direction. Attached to and fixed.

  The light emitting part and its mounting part will be described in more detail. 4 is an enlarged front view of the flat plate portion to which the light source portion is attached, and FIG. 5 is a cross-sectional view taken along the line VV of the flat plate portion shown in FIG. As shown in FIG. 4, in the flat plate portion 311 of the mounting angle 31, the light collecting member 5 is disposed on the most front side. And since the condensing member 5 is transparent, the condensing member 5 and the board | substrate 32 arrange | positioned at the back surface of the condensing member 5 and LED33 are also shown as the continuous line.

  As shown in FIG. 5, in the mounting angle 31, the upper fixing portion 312 is fixed to the chassis 1 with a screw Bt, and the cover 4 is attached to the holding portion 313 with the screw Bt. The flat plate portion 311 is provided with a cut-and-raised portion 314 protruding inside the regular octagonal cylindrical shape, and the circuit board 21 is fixed to the cut-and-raised portion 314 with screws Bt.

  In the illuminating device A provided with such an attachment angle 31, since the circuit board 21 is disposed at the central portion, the central portion is a non-light emitting portion. In the illumination device A, it is preferable that the non-light-emitting portion is small, and the smaller the one side of the regular octagon of the mounting angle 31 is, the smaller the non-light-emitting portion is.

  As shown in FIG. 4, chip-shaped LEDs 33 are mounted on a rectangular substrate 32 attached to the flat plate portion 311. The LED 33 has a rectangular parallelepiped package having a square shape in plan view. On the substrate 32, the LEDs 33 are linearly arranged in the longitudinal direction, and the linear arrangement of the LEDs 33 is arranged in three stages in the lateral direction. Thus, by arranging the LED 33, the length of the substrate in the longitudinal direction can be shortened. Thereby, the length of one side of the regular octagon of the mounting angle 31 is reduced, and the non-light-emitting portion of the illumination device A can be reduced.

  As shown in FIGS. 4 and 5, the substrate 32 has three rows of LEDs 33 arranged in the H direction arranged in the V direction. As shown in FIG. 4, the LEDs 33 at each stage are arranged in the H direction. The LEDs 33 in each stage are arranged at substantially equal intervals, and the number of LEDs 33 is larger in the central stage than in the upper and lower stages. Usually, when the luminous efficiency is the same, the larger the light emitting surface area, that is, the larger the number of LEDs 33, the larger the amount of light emitted. In the case of the light emitting unit 3 in which the LEDs 33 as shown in FIG. 4 are arranged, the light emitted from the central portion is brighter than the light emitted from the upper and lower stages.

  When the light emitted from the light source unit having a plurality of stages of LEDs 33 arranged in the H direction in the V direction is condensed by a conventional collimator lens, the light is directed upward from the upper LED 33. The irradiation range in the V direction of light is wide from the lower LED 33 to the light going downward.

  The LED 33 is a point light source, and the emitted light is divergent light (Lambertian light distribution). The light emitted from the LED 33 has a high luminous flux density in the vicinity of the mounting angle 31. The light flux density of the light applied to the chassis 1 is higher in the light emitted from the LED 33 in the stage near the chassis 1 than in the light emitted from the LED 33 in the other stage. The light having a high luminous flux density is reflected by the chassis 1 and emitted from the cover 4. Further, the light flux density of the light transmitted through the vicinity of the mounting angle 31 of the cover 4 is high from the light emitted from the LED 33 at the stage close to the cover 4.

  From the above, in order to prevent the light flux density of the light transmitted through the cover 4 from being close to the mounting angle 31 from being excessively high, the light emitting unit 3 is arranged at a stage close to the chassis 1 and the cover 4 of the substrate 32. The number of LEDs 33 is smaller than that of the central stage.

  In this way, by changing the number of the LEDs 33 arranged depending on the step of the substrate 32 in the V direction, the variation (luminance unevenness) in the light flux density of the light emitted from the cover 4 can be suppressed. However, it is difficult to sufficiently suppress the luminance unevenness of the light emitted from the cover 4 (that is, to the extent required as a lighting device) only by adjusting the number of LEDs 33 in each stage.

  Further, in the illuminating device configured to emit light from the LED 33 along the cover 4 that is the light emitting surface, the light that spreads from the LED 33 at a predetermined angle (for example, 30 degrees with respect to the optical axis) is the chassis 1 and / or. It is known that as the distance from the position reaching the cover 4 to the LED 33 increases, that is, as the parallel light is approached, the change in the light flux density due to the distance decreases. Therefore, in the illuminating device A, the light-condensing member 5 as shown in FIG.

  Below, the condensing member 5 is demonstrated with reference to drawings. FIG. 6 is an enlarged view of the substrate and the light collecting member attached to the attachment angle. In FIG. 6, the mounting angle 31 is not shown.

  As shown in FIG. 6, the condensing member 5 is formed on the side opposite to the facing surface 50 facing the LED 33 mounted on the substrate 32, and condenses the light emitted from the LED 33 only in the V direction. 52 is formed. On the substrate 32, the LEDs 33 arranged in the H direction are arranged so as to be coaxial or substantially coaxial in the V direction. Therefore, the condensing member 52 has a collimator shape with respect to each array of the LEDs 33 at each stage in the V direction.

  The condensing part 52 of the condensing member 5 has a lens shape that is curved in the V direction and extends in the H direction (here, a collimator lens shape). The light collecting unit 52 is arranged in three stages in the V direction and corresponds to the arrangement of the LEDs 33 arranged in the H direction, and has a shape for collecting the light emitted from the LEDs 33 arranged in each stage in the V direction. It has become. In addition, the shape of the condensing part 52 is not limited to a collimator lens shape, What is necessary is just an optical element which can condense in the V direction of LED32, for example, a cylindrical lens may be used. Further, the condensing units 52 at each stage may have different shapes or the same shape. In the light collecting member 5 shown in FIG. 6, the light collecting portions 52 have different shapes.

  As shown in FIGS. 4, 5, and 6, the substrate 32 and the light collecting member 5 are fastened and fixed to the flat plate portion 311 with screws Sc. A through hole is formed in the substrate 32 and is fixed through the through hole. A spacer 51 is formed on the surface of the light collecting member 5 facing the substrate 32, and the spacer 51 is in contact with the substrate 32, thereby preventing the light collecting member 5 from contacting the LED 33. In FIG. 5, the screw Sc passes through the spacer 51 of the light collecting member 5. However, the present invention is not limited to this, and the screw Sc may pass through a portion other than the spacer 51 of the light collecting member 5.

  The effects of the present invention will be described with reference to the drawings. First, after describing the light source unit, the effect of the illumination device including the light emitting unit will be described. In order to examine the effect of the light source unit of the present invention, a light emission simulation was performed together with the conventional light source unit. FIG. 7A is a diagram showing an optical path of light emitted from a conventional light source unit, and FIG. 7B is a diagram showing an optical path of light emitted from a light source unit used in the present invention.

  First, the shape of the LED and the total luminous flux will be described. Normally, the total luminous flux of an LED is proportional to the area of the light emitting surface (light emitting surface area), assuming that the luminous efficiency is the same. The LED of the light source unit of the illumination device of the present invention has the same light emitting surface area as that of a conventional LED, and adopts a LED divided into a plurality of parts. For example, when a conventional LED uses one LED having a light emitting surface area of 2 mm square, the present invention has a configuration in which 1 mm square LEDs are arranged at intervals of 1 mm vertically. The light emitting surface area is adjusted to be the same. The conventional light emitting unit includes a condensing member having one lens shape, and the light source unit used in the present invention includes two condensing units on the upper and lower sides. The other parts have the same configuration.

  In the conventional light source part, since the light emission surface of LED is large, the lens provided with the large condensing part (collimator lens shape part) corresponding to it is needed. On the other hand, in the light emitting unit used in the present invention, although the area of the region where the LEDs are arranged is large, the light emitting surface of the LED 33 is small, and the light collecting unit includes a light collecting unit corresponding to each of the LEDs 33 in the V direction. Although the arrangement area of the LED 33 is substantially increased by using the member 5, the thickness of the light source unit can be suppressed to the same level as that of the conventional light source unit.

  The simulation was performed under the above conditions. 7A and 7B show an optical path of light emitted from the LED at a constant irradiation angle (30 degrees) from the central axis. 7A and 7B, the lower part is the light emitting surface. Furthermore, as shown in FIG. 7A, in the conventional lighting device, the distance from the LED to the point where the emitted light reaches the light emitting surface is a distance L1, and as shown in FIG. 7B, in the lighting device of the present invention. The length from the LED to the point where the emitted light reaches the light emitting surface is the distance L2.

  As shown in FIGS. 7A and 7B, the distance L2 is longer than the distance L1. As described above, when light is emitted from the LED along the light emission surface, the light flux density on the light emission surface is less likely to vary as the length from the point reaching the light irradiation surface to the LED is longer. is there. Since the distance L1 <L2, it can be seen that in the light source unit of the present invention, the light flux density of light transmitted through the light exit surface is less likely to vary than the conventional light source unit.

  A comparison was also made with respect to an illumination device including a light source unit in which the conventional light source unit as described above and the light source unit used in the present invention are arranged as shown in FIG. 8 is a diagram showing a luminance distribution of light emitted from a conventional illumination device, FIG. 9 is a diagram showing a luminance distribution of light emitted from the illumination device according to the present invention, and FIG. 10 is a diagram showing conventional illumination. It is a figure which shows the luminance distribution along the diameter of the light radiate | emitted from an apparatus and the illuminating device of this invention.

  As shown in FIG. 8, in the illumination device having the conventional configuration, the luminance is high in the vicinity of the light source unit, and the luminance is low in the outer peripheral portion of the illumination device. On the other hand, as shown in FIG. 9, in the illumination device of the present invention, the luminance does not decrease much even in a portion away from the light source unit. That is, it can be seen that the light emitted from the illumination device of the present invention is light with less luminance unevenness than the light emitted from the conventional illumination device. Moreover, as shown in FIG. 10, it turns out that the brightness | luminance emitted from the illuminating device of this invention is high compared with the conventional illuminating device.

  Thus, it can be seen that the illumination device of the present invention can emit light with high luminance with less luminance unevenness than the conventional illumination device. Further, even when a plurality of LEDs are provided, the length in the short direction of the substrate on which the LEDs are mounted is substantially the same as that in the case where a single row of LEDs having the same total luminous flux is used, and the length in the longitudinal direction. Can be shortened. For this reason, when the LEDs having the same total luminous flux are used, the light emitting portion can be reduced, and the non-light emitting portion formed in the central portion of the lighting device can be reduced.

  The light emitting unit 3 described above is an example of the present invention, and the present invention is not limited to this. Even in a structure in which the arrangement of the LEDs 33 arranged in the H direction is two or four or more in the V direction, It goes without saying that an equivalent effect can be obtained by using a light collecting member having a corresponding light collecting portion.

(Second Embodiment)
Another example of the lighting device according to the present invention will be described with reference to the drawings. FIG. 11 is a cross-sectional view of a light collecting member used in another example of the illumination device according to the present invention. The illuminating device shown in the present embodiment has the same configuration as the illuminating device shown in FIG. 1 and the like except that the shape of the light collecting member 5B is different, and substantially the same parts are denoted by the same reference numerals and details of the same parts are shown. The detailed explanation is omitted.

  The condensing member 5 condenses the light emitted from the LED 33 in the thickness direction. In order to increase the length from the LED 33 to the point where the light is applied to the cover 4, it is preferable to direct the light emitted from the upper and lower LEDs toward the center. In order to efficiently emit light emitted from the LED 33 from the cover 4, it is preferable to irradiate the cover 4.

  Therefore, as shown in FIG. 5, in the condensing member 5 </ b> B, the facing surface 502 facing the lower LED 33 and the facing surface 503 facing the upper LED 33 are inclined to the facing surface 501 facing the central LED 33. ing. Note that the tilt angles may be the same or different. In the case of different configurations, it is preferable that the inclination angle of the facing surface 503 facing the upper LED 33 is larger than the tilt angle of the facing surface 502 facing the lower LED 33.

Further, the normal line of the facing surface 501 facing the central LED 33 may be inclined so as to face the cover 4. That is, as in the light collecting member 5B shown in FIG. 11, the facing surface 501 facing the LED 33 may be inclined with respect to the light emitting surface of the LED 33 (that is, the substrate 32). And in the condensing member 5B, it is set as the inclination which is different for each of the arrangement | sequence of 3 steps | paragraphs. The absolute value of the angle formed between the opposed surface 501 facing the center LED 33 and the substrate 32 is θ1, the absolute value of the angle formed between the opposed surface 502 facing the lower LED 33 and the substrate 32 is θ2, and the upper LED 33 When the absolute value of the angle formed by the opposed surface 503 and the substrate 32 is θ3, the following condition is satisfied.
θ2 <θ1 <θ3

  By angling in this way, the light emitted from the upper LED 33 can be directed to the cover 4 as much as possible, and it is possible to suppress the light beam from being attenuated by the reflection of the light on the chassis 1, It is possible to increase the use efficiency.

  In the above-described example, the LED 33 is described as being arranged in three rows in the V direction in a row in which the LEDs 33 are arranged in the H direction. In the case of an odd number of steps, the same effect can be obtained by inclining the steps on both sides around the center step.

(Third embodiment)
Still another example of the illumination device according to the present invention will be described with reference to the drawings. FIG. 12 is a cross-sectional view of a light collecting member used in another example of the illumination device according to the present invention. The illuminating device shown in the present embodiment has the same configuration as the illuminating device shown in FIG. 1 and the like except that the shape of the light collecting member 5C is different, and substantially the same parts are denoted by the same reference numerals and details of the same parts are shown. The detailed explanation is omitted.

  As shown in FIG. 12, in the light collecting member 5 </ b> C, the light emitting surface of the LED 33 is disposed on each of a facing surface 501 facing the central LED 33, a facing surface 502 facing the lower LED 33, and a facing surface 503 facing the upper LED 33. A lens surface having an inflection point in the vicinity of the front surface and having the same cross section in the H direction is formed.

  A simulation was performed on the effect when the opposing surfaces 501, 502, and 503 facing the LED were formed on the lens surface. FIG. 13 is a diagram illustrating the light irradiation direction when the surface facing the LED is a flat surface and when the lens surface has an inflection point near the front surface of the light emitting surface. FIG. 13 shows an optical path irradiated from the central axis at a fixed irradiation angle (30 degrees) among the light emitted from the light source, and the lower side is the light emitting surface.

  As can be seen from the two simulation results in FIG. 13, the optical path of the light emitted from the LED 33 reaches the light emitting surface at a position away from the LED 33 when the opposite surface is the lens surface. From this, it can be seen that the configuration in which the surface facing the LED 33 is a lens surface improves the straightness of light and changes in the light flux density on the light exit surface are less likely to occur.

  In the present embodiment, the lens surface is formed such that the two planes are joined together and the joining portion, which is an inflection point, is formed in the vicinity of the front surface of the light emitting surface of the LED 33. However, the present invention is not limited to this. For example, a lens surface having a concave shape on the inner side of the condensing member 5C having a cross-sectional shape such as an arc, an elliptical arc, or a parabola can be widely used. Of course, the LED stage is not limited to three stages.

  In each of the above-described embodiments, the lighting device is a so-called ceiling lamp of the type attached to the ceiling, but is not limited to the ceiling lamp as long as it includes a chassis having a reflecting portion, for example, The configuration of the lighting device of the present invention can also be used for hanging type lighting or the like.

(Fourth embodiment)
In each of the above-described embodiments, the light emitting unit 3 is attached to the central portion of the circular chassis 1. Although it is difficult with the circular chassis 1, it is also possible to arrange the light emitting part at the edge of the chassis by using a polygonal chassis. Accordingly, an illumination device in which a light emitting unit is arranged on the edge of the chassis will be described with reference to the drawings. FIG. 14 is an exploded perspective view of another example of a lighting device according to the present invention.

  As illustrated in FIG. 14, the lighting device B includes a chassis 6 that is rectangular in plan view and a cover 60 that covers the chassis 6. The chassis 6 is formed by cutting and bending a metal plate, and includes a rectangular flat plate portion 61 and side wall portions 62 formed by bending each side of the flat plate portion. And as shown in FIG. 14, the light source part including the board | substrate 32 with which LED33 was mounted, and the condensing member 5 is attached along with the side wall part 62 formed by bending the short side of the flat plate part 61 of the chassis 6. As shown in FIG. .

  That is, in the lighting device B, a part of the side wall portion 62 functions as an attachment angle. Therefore, the mounting angle can be omitted. Further, the flat plate portion 61 of the chassis 6 is configured to efficiently reflect the light from the LED 33 toward the cover 60 side. Examples of the treatment of the flat plate portion 61 include well-known ones such as white coating and reflection sheet pasting.

  And the cover 60 of the side wall part 62 of the chassis 6 is attached and fixed. Since the cover 60 has the same configuration except that the shape of the cover 60 is different from that of the cover 4 of the illumination device A, the details are omitted. Although not shown, the drive control unit 2 is attached to the back surface of the flat plate portion 61. In the illuminating device B having such a configuration, the drive control unit 2, the mounting angle 3, and the like are not arranged in the central portion of the illuminating device, so that the non-light-emitting portion can be reduced or eliminated. It is possible to reduce unevenness in the brightness of the emitted light.

  When the lighting device B is attached to the ceiling, a circular through-hole 610 as shown by a two-dot chain line is formed in the flat plate portion 61, and a connector arranged on the ceiling passes through the 610, and the flat plate portion 61. May be fixed. In addition, although it is set as the rectangular thing as the illuminating device B, it is not limited to this, For example, square shape may be sufficient, and polygonal shapes other than a square may be sufficient.

  Moreover, in the illuminating device B, although LED33 and the condensing member 5 (light source part) are arrange | positioned at the side wall part 62 formed in the short side of the flat plate part 61, it is not limited to this, Long side You may arrange | position to the formed side wall part. Moreover, the structure which arrange | positions a light source part to each of the side wall part formed in both the short side and the long side may be sufficient.

(Fifth embodiment)
Since the illuminating device of the present invention emits planar light from the light emitting surface, it can also be used as a backlight of a liquid crystal display device.

  Hereinafter, an example in which the illumination device of the present invention is used as a backlight of a liquid crystal display device will be described with reference to the drawings. FIG. 15 is an exploded perspective view showing an example of a liquid crystal display device according to the present invention.

  As shown in FIG. 15, the liquid crystal display device 8 includes a liquid crystal panel unit 81 and a backlight unit 82. In the liquid crystal display device 8, a liquid crystal panel unit 81 is arranged on the front side (observer side) of the backlight unit 82, and the liquid crystal panel unit 81 is placed on a metal bezel 83 having an opening window 830 in the center on the front side. It is being held down.

  The liquid crystal panel unit 81 includes a liquid crystal panel 811 in which liquid crystal is sealed, and a polarizing plate 812 attached to the front surface (observer side) and the back surface (backlight unit 1 side) of the liquid crystal panel 811. The liquid crystal panel 811 includes an array substrate, a counter substrate 814 arranged to face the array substrate 813, and a liquid crystal filled between the array substrate and the counter substrate.

  The array substrate 813 is provided with a source wiring and a gate wiring orthogonal to each other, a switching element (for example, a thin film transistor) connected to the source wiring and the gate wiring, a pixel electrode connected to the switching element, an alignment film, and the like. The counter substrate 814 is provided with a color filter in which colored portions of red, green, and blue (RGB) are arranged in a predetermined arrangement, a common electrode, an alignment film, and the like.

  In the liquid crystal panel unit 81, a voltage is applied between the array substrate 813 and the counter substrate 814 in each pixel of the liquid crystal panel 811 by driving the switching element. When the voltage between the array substrate 813 and the counter substrate 814 changes, the liquid crystal in each pixel rotates and light is modulated (the degree of light transmission is changed). As a result, an image is displayed in the image display area on the viewer side of the liquid crystal panel 811.

  The bezel 83 is a metal frame and has a shape that covers the edge portion of the front surface of the liquid crystal panel unit 81. The bezel 83 includes a rectangular opening window 830 formed so as not to hide the image display area of the liquid crystal panel unit 81, a pressing portion 831 that presses the liquid crystal panel unit 81 from the front side, and a rear surface from the edge of the pressing portion 831. And a cover portion 832 that covers the edges of the liquid crystal panel unit 81 and the backlight unit 82. The bezel 83 is grounded and shields the liquid crystal panel unit 81 and the backlight unit 82.

  The backlight unit 82 is an illumination device that irradiates the liquid crystal panel unit 81 with planar light. The backlight unit 82 has a structure equivalent to that of the lighting device shown in the first embodiment. That is, the backlight chassis 821 having a rectangular bottom corresponding to the chassis 1 and the light source unit 823 corresponding to the light emitting unit 3 are provided. Since the backlight unit 82 is a member having a rectangular bottom surface, the light source unit 823 is disposed on both short sides. And although illustration is abbreviate | omitted, the control circuit part is attached and arrange | positioned at the surface of the back side of a bottom face. An optical sheet member 822 for diffusing outgoing light and increasing luminance is disposed on the light outgoing surface side of the backlight unit 82.

  The structure of the light source unit 823 has substantially the same structure as that of the light emitting unit 3 except that the substrate is arranged in a straight line. That is, a plurality of substrates 32 and light collecting members 5 on which the LEDs 33 shown in FIG. 4 are mounted are attached to the short side. In the backlight unit 82, since the light source unit 823 is attached to the outer peripheral portion of the backlight chassis 821, the side wall portions that are raised from the sides of the rectangular bottom surface are formed to form the attachment angle. Can be used as

  Such a backlight unit 82 can emit planar light with less luminance unevenness than the light emitting surface facing the bottom without using a light guide plate, and the number of components can be reduced accordingly. is there.

  The liquid crystal display device shown in the present embodiment can be employed in, for example, a mobile phone, a tablet PC, a display device for home appliances, a television receiver, and the like.

  In each of the above-described embodiments, a ceiling lamp or a backlight of a liquid crystal display device is given as the illumination device. However, in addition to these, it can also be used as a back-side illumination device that illuminates from the back of an electric signboard or the like. Is possible.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this content. The embodiments of the present invention can be variously modified without departing from the spirit of the invention.

  The illuminating device according to the present invention emits light with less unevenness in luminance, and is therefore attached to the ceiling of a living room or the like, and can be used as a backlight for a lighting fixture or a liquid crystal display device that irradiates the entire light.

DESCRIPTION OF SYMBOLS 1 Chassis 2 Drive control part 20 Insulation sheet 21 Circuit board 22 Support part 23 Support part 3 Light emission part 31 Mounting angle 311 Flat plate part 312 Fixing part 313 Holding part 32 Board | substrate 33 LED
4 Cover 5 Condensing member 50 Opposing surfaces 501, 502, 503 Opposing surfaces (corresponding to LED arrangement)
51 Spacer 52 Condensing part (collimator lens)

Claims (10)

A housing having a reflecting portion facing the light emitting surface;
A substrate in which LEDs are arranged linearly in a first direction that is a direction along the reflecting portion, and a plurality of stages of the LEDs are formed in a second direction intersecting the first direction;
A condensing member that is disposed so as to face the surface of the substrate on which the LED is mounted, and that condenses light emitted from the LED in the second direction;
The light emitted from the LED to the substrate and the light collecting member is attached to the housing so that the light follows the reflecting portion,
The condensing member is provided with a condensing part for condensing light emitted from the LED in the second direction for each array of the LEDs,
The lighting device, wherein a surface of the condensing member facing the LED is inclined with respect to a light emitting surface of the LED so as to correspond to each of the LED arrays.   The lighting device according to claim 1, wherein the light collecting unit is a collimator-shaped convex lens formed on a surface opposite to a surface facing the LED. The lighting device according to claim 1, wherein an inclination of a surface of the light condensing member facing the LED is increased as a distance from a central portion in the second direction is increased.   2. The concave lens surface having an inflection point in the vicinity of the front surface of the light emitting surface of the LED so that the surface of the condensing member facing the LED corresponds to each of the LED arrays. Item 4. The lighting device according to any one of Items 3 to 4.   The lighting device according to claim 4, wherein the lens surface has a shape obtained by connecting two flat surfaces.   The board | substrate with which said LED was mounted, and the said condensing member are attached to the outer surface side of the attachment part formed in the polygonal cylindrical shape arrange | positioned in the center part of the said housing | casing. The lighting device according to any one of 5.   The said housing | casing has a rectangular flat plate part, The said board | substrate and the said condensing member are attached to the wall body which protruded from the at least one side of the said flat plate part. Lighting equipment.   The backlight using the illuminating device of Claim 7.   A liquid crystal display device comprising the backlight according to claim 8.   A television receiver comprising the liquid crystal display device according to claim 9.