JP2007080531A - Light-emitting diode lighting fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED lighting fixture with a low-profile light guide plate without degrading light utilization efficiency of an LED. <P>SOLUTION: The LED lighting fixture is provided with a light guide plate 1 having an incident face 1a of light on a left end face, a mounting substrate with LEDs 3 as a light source mounted on its top face and arranged in the vicinity of the incident face 1a so that a plane direction of a light-irradiating face 3a and a plane direction of the incident face 1a nearly cross each other, a reflecting member 4 reflecting light of the LEDs 3 and making it incident into the light guide plate 1 from the incident face 1a of the light guide plate 1, and a case 5 housing these. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an LED lighting apparatus using an LED as a light source, and more particularly to an edge light type LED lighting apparatus.

Conventionally provided edge light type LED lighting fixtures include a strip-shaped mounting substrate on which a plurality of LEDs are mounted on one surface, a light guide plate used for a translucent decorative plate, etc., and a light incident surface. There is provided a structure in which one end surface of the light guide plate and the light emitting surface of the LED mounted on the strip substrate are opposed to each other, and the light of the LED enters the light guide plate from one end surface of the light guide plate ( For example, Patent Document 1).
Japanese Patent Laid-Open No. 6-312600 (FIG. 4)

  By the way, since said light-guide plate is formed using a glass plate or an acrylic board, it becomes a factor of the increase in the weight of LED lighting fixture, and cost increase. Therefore, it is desired to reduce the weight and cost of the LED lighting fixture by reducing the thickness of the light guide plate.

  However, in the conventional LED lighting apparatus, when the thickness of the light guide plate is reduced, the area of the one end surface serving as the incident surface of the light guide plate is also reduced, and this reduces the amount of incident light of the LED light to the light guide plate. As a result, the LED light utilization efficiency deteriorates, resulting in a new problem that the brightness of the LED lighting apparatus becomes dark.

  The present invention has been made in view of the above points, and an object thereof is to provide an LED lighting apparatus capable of reducing the thickness of a light guide plate without deteriorating the light use efficiency of the LED.

  In order to solve the above problems, in the invention of the LED lighting apparatus according to claim 1, the light guide member having a light incident surface on one end surface, the surface direction of the light emitting surface and the surface direction of the incident surface intersect. As described above, an LED disposed in the vicinity of the incident surface and a reflecting member that reflects the light of the LED and enters the light guide member from the incident surface are provided.

  In the present invention, since the light of the LED is incident from the incident surface of the light guide member into the light guide member by the reflecting member, the light of the LED is transmitted without any problem even if the area of the incident surface is reduced. This makes it possible to reduce the thickness of the light guide plate without deteriorating the light utilization efficiency. As a result, the light weight and the cost can be reduced. is there.

  An embodiment of the present invention will be described below with reference to FIG. In the following description, the upper side of FIG. 1 (a) is the upper side of the LED lighting fixture, the lower side of FIG. 1 (a) is the lower side of the LED lighting fixture, and the right side of FIG. 1 (a) is the right side of the LED lighting fixture. The left side of FIG. 1A is the left side of the LED lighting apparatus.

  As shown in FIG. 1A, in the LED lighting apparatus of the present embodiment, a light guide plate 1 having a light incident surface 1a on one end surface (left end surface) and an LED 3 serving as a light source are mounted on one surface (upper surface). In addition, the light emitting surface 3a of the LED 3 and the mounting substrate 2 disposed in the vicinity of the incident surface 1a so that the surface direction of the incident surface 1a is substantially orthogonal to each other, and the light of the LED 3 is reflected to reflect the light of the light guide plate 1. A reflecting member 4 that enters the light guide plate 1 from the incident surface 1a and a housing 5 that houses them are provided.

  As shown in FIG. 1B, the light guide plate 1 is, for example, a single-sided light emitting type that emits light only on the upper surface, and is formed in a rectangular plate shape using a light-transmitting material such as glass or acrylic. The left end surface of the LED 3 is used as the light incident surface 1a. In addition, a V-shaped groove (not shown) for emitting light transmitted through the light guide plate 1 to the outside is provided on the lower surface, and light emitted downward from the V-shaped groove. A reflection sheet (not shown) is provided for reflecting the light upward and performing a predetermined light emission display. By the way, the above-mentioned V-shaped grooves (not shown) are provided so that the distance between the grooves becomes narrower (the density becomes higher) as the distance from the left end side to the right end side of the light guide plate 1, that is, from the incident surface. Thus, the light emitting surface (upper surface) of the light guide plate 1 is homogenized.

  The mounting substrate 2 is a so-called metal base substrate that also serves as a heat dissipation plate for the LED 3. For example, an aluminum substrate (aluminum base substrate) excellent in heat dissipation, workability, shielding properties, etc. is used as shown in FIG. It is formed in a long flat plate shape. On the upper surface of the mounting substrate 2, wiring patterns for electronic components including the LEDs 3, for example, a plurality (eight in the present embodiment) of surface-mounting LEDs 3 are disposed with the light emitting surface 3 a facing upward and the length of the mounting substrate 2. A wiring pattern (not shown) for mounting on the mounting substrate 2 is provided so as to be arranged in the direction. By mounting the LED 3 and an electronic component (not shown) on this wiring pattern, power from an external power source is provided. A lighting circuit for causing the LEDs 3 to emit light is configured by supply.

  The LEDs 3 mounted on the mounting substrate 2 are sealed with a light-transmitting resin such as silicon, thereby improving the waterproofness and heat dissipation of the LED 3. Further, in this embodiment, eight LEDs 3 are arranged in one row on the mounting substrate 2, but for example, eight LEDs 3 may be arranged in two rows to provide a total of 16 LEDs 3. What is necessary is just to change suitably the number of LED3 according to a condition.

  The housing 5 is made of, for example, a resin molded product, and as shown in FIG. 1A, a long bottom portion 5a to which the mounting substrate 2 is fixed, and one end side in the short direction of the bottom portion 5a (FIG. 1). (A) (right end side) and a side plate portion 5b that is suspended upward from both ends in the longitudinal direction and to which the light guide plate 1 is fixed, and is provided in the short direction of the upper end portion of the side plate portion 5b and the bottom portion 5a. A substantially arc-shaped lid 5c that connects the other end (the left end in FIG. 1A) is provided. A member (not shown) for fixing the mounting board 2 and a power line insertion slot (not shown) for inserting an external power line connected to the mounting board 2 into the housing 5 are provided on the bottom 5a. Etc. are provided. In addition, the side plate portion 5 b is provided with a substantially rectangular opening 5 d for inserting the left end side of the light guide plate 1 into the housing 5.

  On the other hand, the reflection member 4 is attached to the inner surface of the lid 5c. Here, the reflecting member 4 is made of a metal material having a high light reflectance such as aluminum, for example, and reflects light from the light emitting surface 3 a of the LED 3 of the mounting substrate 2 toward the incident surface 1 a side of the light guide plate 1. Such a surface shape (for example, an arcuate concave shape whose cross section has a central angle of about 90).

  As described above, the LED lighting apparatus of the present embodiment includes the light guide plate 1, the mounting substrate 2 on which the LEDs 3 are mounted, and the housing 5 including the reflecting member 4 as shown in FIG. The mounting substrate 2 is fixed to the bottom 5a of the housing 5, and the light guide plate 1 has the incident surface 1a facing the inside of the housing 5 from the opening 5d of the side plate 5b of the housing 5. It is fixed with.

  The mounting substrate 2 and the light guide plate 5 are fixed to the housing 5 in this way, so that the surface direction of the light emitting surface 3a of the LED 3 and the surface direction of the incident surface 1a of the mounting substrate 2 are substantially orthogonal to each other. The light guide plate 1 is disposed in the vicinity of the incident surface 1a. Note that it is preferable that the light emitting surface 3a of the LED 3 and the lower surface of the light guide plate 1 are located on substantially the same plane in consideration of the utilization efficiency of the light emitted from the LED 3 to the right side.

  Next, operation | movement of the LED lighting fixture of this embodiment is demonstrated. When the LEDs 3 provided on the mounting substrate 2 are turned on by power supply from an external power source, each LED 3 emits light, and this light spreads in all directions from the light emitting surface 3a. The light traveling in the direction is incident on the light guide plate 1 from the incident surface 1a as it is, while the light traveling left from the LED 3 is reflected rightward by the reflecting member 4 and then enters the light guide plate 1 from the incident surface 1a. Is done. Thus, the light incident on the light guide plate 1 is transmitted from the left end side to the right end side while being totally reflected in the light guide plate 1, and a part of the light is V-shaped provided on the lower surface of the light guide plate 1. The light is emitted outward from the lower surface of the light guide plate 1 through a groove (not shown). Then, the light emitted outward from the light guide plate 1 is reflected by a reflection sheet (not shown) provided on the lower surface of the light guide plate 1, passes through the light guide plate 1 again, and from the light emitting surface of the light guide plate 1. It is emitted and illuminates the surroundings.

  As described above, the LED lighting apparatus of the present embodiment uses the reflecting member 4 to cause the light of the LED 3 to enter the light guide plate 1 from the light entrance surface 1a. Even when the area is reduced, the amount of light incident on the light guide plate 1 from the incident surface 1a can be ensured, so that the light of the LED 3 can be incident on the light guide plate 1 without any problem. It is possible to reduce the thickness of the light guide plate 1 without deteriorating, and as a result, it is possible to reduce the weight and the cost.

  By the way, in the above example, the surface direction of the light emitting surface 3a of the LED 3 and the surface direction of the incident surface 1a are orthogonal to each other, but the angle between the surface direction of the light emitting surface 3a and the surface direction of the incident surface 1a is The angle is not limited to a right angle as long as the light from the LED 3 can be reflected by the reflecting member 4 and incident on the incident surface 1a.

  On the other hand, in the light guide plate 1, the light emitting surface of the light guide plate 1 is leveled by the density of the V-shaped grooves. For example, as the distance from the left end side to the right end side of the light guide plate 1, that is, from the incident surface, Even if the size of the groove is increased, the light emitting surface (upper surface) of the light guide plate 1 can be similarly leveled, and the light emitting surface can be leveled by a combination of the density and size of the grooves. You may do it. Furthermore, in the above example, a V-shaped groove is used, but such a groove is not limited to a V-shaped groove, and various shapes can be used. It should be noted that white ink may be used on the light emitting surface, and dots having a pattern with better light shielding performance toward the left end side may be printed, and this also aims at equalizing the light emitting surface of the light guide plate 1. Can do.

  The light guide member for the light from the LED 3 is not limited to the single-side light-emitting type light guide plate 1 as described above, but for example, a double-sided light-emitting type, a combined double-sided light-emitting type, or a flexible You may make it use the light guide sheet formed in the sheet form using the translucent resin etc. which have this.

  In addition, the reflecting member 4 is not limited to the metal material, and the light of the LED 3 may be reflected to the incident surface 1a side using a prism or the like, and the shape of the housing 5 of the LED lighting apparatus is It is not restricted to said example, What is necessary is just to make it suitable according to a condition.

(A) is a schematic sectional drawing of the LED lighting fixture of this invention, (b) is a perspective view same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light guide plate 1a Incident surface 2 Mounting board 3 LED
3a Light emitting surface 4 Reflecting member 5 Housing

Claims (1)

  A light guide member having a light incident surface on one end surface, an LED disposed in the vicinity of the incident surface so that the surface direction of the light emitting surface and the surface direction of the incident surface intersect, and the light of the LED is reflected And a reflecting member that enters the light guide member from the incident surface.

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