JP2009223069A - Led illuminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new illuminator using an LED as a light source, which has not been provided hitherto. <P>SOLUTION: The illuminator 10 using the LED as the light source includes an irradiation member 20 arranged on the inside of a side surface 12 formed nearly in a perpendicular direction to a light emitting surface 11 of the illuminator 10, and a reflection member 60 bending the light from the irradiation member 20 to the light emitting surface 11. Then, the irradiation member 20 includes a plurality of LEDs 30, in a longitudinal direction of an irradiation member body 21, and formed by attaching a primary lens 40 and a secondary lens 50 to each of the LEDs 30. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an illumination device using an LED as a light source.

In order to prevent global warming, there is a demand for energy saving in lighting devices such as signboards in order to suppress CO2 emissions.
In response to this, various lighting devices have been developed in which the light source is replaced with an energy-saving LED from a fluorescent lamp.

  Among these, Patent Document 1 discloses a box having an open front surface, at least two wiring boards disposed opposite to each other in parallel to the side wall portion of the box, and a plurality of light emitting devices installed on the wiring board. A light box comprising an element, a light reflecting plate disposed at the bottom of the box, and a translucent light diffusing surface plate installed in a front opening of the box, wherein the light reflecting plate is A convex portion protruding toward the front opening of the box, h being the distance between the bottom of the box and the lowest light emitting part of the light emitting element, and the bottom of the box and the light diffusion surface plate A light box that satisfies “h <L ≦ (h + d) / 2”, where d is the distance between the bottom of the box and the apex of the peak-shaped convex portion. is there.

By the way, the parabolic curved mirror reflector that irradiates light in the forward direction is suitable for irradiating light forward, but the light reflected by the parabolic curved mirror surface provided for reflection is inverted and refracted. The light emitted from the LED cannot be irradiated in a straight line.
In addition, the parabolic curved mirror reflector needs a depth in the shape of the curved surface, and the vertical thickness of the irradiation member cannot be reduced. Therefore, even if the light emitting position of the LED is the same, the parabolic curve The distance to the front end of the specular reflector becomes thicker than that of the thin front irradiation lens, which increases the configuration of the irradiation member and increases the mounting area.

JP 2006-202729 A

However, Patent Document 1 has the following problems.
(1) In Patent Document 1, a plurality of light emitting elements (LEDs) arranged in one or more rows in the longitudinal direction on a wiring board is used (see “0012” and the same specification). Since the LED as the light source is used as it is, it becomes a light box of a size limited to the reachable distance of the LED light.
That is, as shown in FIG. 4A, the LED light has a property of diffusing in the irradiation angle direction from 65 degrees to 140 degrees for mounting LEDs and from 15 degrees to 50 degrees for bullet-type LEDs.
Accordingly, the light reaching distance is extremely short, and the light box has to have two reflecting surfaces with sizes corresponding to the short reaching distance.
(2) Similarly, the LED light is a product with the minimum irradiation angle of the LED, the mounting type is 65 degrees, and the shell type is diffused to 15 degrees. A brightly mounted LED has a wide minimum illumination angle product and is suitable for light diffusion, but is not suitable for irradiating far away in a narrow range. Even though the bullet-type LED has a minimum irradiation angle of 15 degrees, the optical axis thickness of the light source part is as thin as 5 mm, and is about 30 mm at a distance of 100 mm from the light source, ensuring a uniform amount of light as the light for lighting the lighting device Cannot (light intensity is dispersed).
However, if the number of LEDs is increased, it will be contrary to energy saving and it will be a factor of high cost. In addition, the amount of heat emitted from the LEDs increases in proportion to the number of LEDs, which causes a reduction in the lifetime of the LEDs.
(3) It is also conceivable to use a high-intensity LED (high power LED) as means for compensating for the shortage of light. However, if a high-brightness LED is used, the light emission heat generation amount naturally increases accordingly, and unless the heat dissipation process is eliminated, the use of the high-brightness LED is impossible (the light source and heat dissipation must be considered as one). .
(4) Even if the light that is the point light source of the LED element can be a surface light source that irradiates the LED package at a certain angle, the light is diffused as it is, and the light that goes straight is provided at the tip of the LED package. Even with the convex lens effect, the light beam can be collected, but it cannot be thickened as a straight beam.
(5) Unlike the light guide plate method using a transparent resin plate, the reflection sheet is not light that can be reflected only at a certain angle. Therefore, if the reflection surface does not constitute a reflection surface corresponding to light incident from a different angle, the reflection sheet is reflected. The face cannot be used effectively.

Therefore, the present invention has been completed by the present inventors, who should achieve the following object.
(1) It can cope with a large-sized lighting device.
(2) The number of LEDs can be reduced as much as possible.
(3) It can cope with high brightness of LED (realization of heat dissipation)
(4) Applicable to existing lighting devices.
(5) The effective area of the light emitting surface of the lighting device can be increased.
(6) Shadows can be reduced even on the light emitting surface of the illumination device having irregularities.

To achieve the above objective,
1st invention is the illuminating device which uses LED for the light source, Comprising: The irradiation member arrange | positioned inside the side surface formed in the substantially perpendicular direction with respect to the light emission surface of an illuminating device, and the light emission surface from the irradiation member And an irradiation member provided with a plurality of LEDs in the longitudinal direction of the side surface, and attached with a primary lens that extends the reach of light to each LED.
Here, the “primary lens” refers to a reflective lens for emitting light emitted from a light emitting element in an LED, thickening the light emitted by reflecting the LED package in which the element is incorporated, and irradiating in the forward direction. A thin reflective lens (see JP 2006-202729 A) is preferable.
The second invention uses a thin lens that linearly irradiates the light emitting part of the illumination member and the emitted light with an acute angle of 95% or more forward with a primary lens, so that the thickness of a parabolic curved reflector is reduced. It is unnecessary, and since it does not cause reflection / refraction of light that always appears in the parabolic curved reflector, the space for the focal depth is also unnecessary, and the refraction space when using the secondary lens is unnecessary, and the structure of the irradiation member is made thin. be able to. By reducing the thickness in this way, a large reflecting surface in the illuminating device can be obtained, and as a result, the illuminating device surface emitting area can be increased.
In the third aspect of the invention, the irradiation member is provided with a plurality of LEDs in the side surface longitudinal direction, and the primary lens that extends the light reach distance to each LED and the light emitted for diffusing and irradiating light in the vicinity. The LED illumination device is characterized in that a secondary lens having two purposes of diffusing is attached.
Here, the “secondary lens” is a diffusing lens. For example, there are concave lenses, aspherical lenses, corrugated lenses, cylindrical lenses, lenticular lenses, fine concavo-convex diffusing lenses, etc., which are molded or plate-shaped or sheet-shaped lenses. A plate lens is preferred.
The light diffusion directionality means that when each LED is combined with a primary lens and a plurality of primary lenses are arranged in close contact, the light is in a state where thick light is arranged due to the primary lens effect. There is no need for diffusion in the direction, which refers to target diffusion in the left-right direction with respect to the array of LEDs.
However, when the light is directly viewed, an all-around diffusing lens regardless of the light diffusing direction is preferable when the primary lenses are arranged in a non-contact state.
In addition, the light that is incident on the secondary lens can be obtained with a uniform diffused irradiation by using a method in which the light that has been previously spread according to the irradiation angle is spread with the secondary lens. By irradiating the secondary lens having a flat surface or curved surface including light slightly diffused when the lens (primary lens) is used, the light can be used as irradiating light without waste.
According to a fourth aspect of the present invention, there is provided the LED illumination device characterized in that the irradiation angle of the irradiation member with respect to the reflection member can be adjusted.
In addition, by providing the irradiation position of the irradiation member on the light emitting surface side with respect to the reflection member from the center line of the irradiation device vertical surface, and adjusting the irradiation angle, the reflection configuration angle of the irradiation device can be lowered.
5th invention is the LED lighting apparatus characterized by a reflection member being a resin sheet or a mirror surface board.
Here, the “resin sheet” includes a resin sheet obtained by laminating an aluminum plate (for strength reinforcement) and an aluminum vapor-deposited resin sheet obtained by vapor-depositing aluminum.
The “mirror plate” includes an aluminum vapor-deposited mirror plate on which aluminum is vapor-deposited, and an aluminum vapor-deposited mirror plate that has been subjected to pattern printing with a diffusion resin.
The reflection sheet mounting structure is a method of providing a three-stage reflection angle from the LED irradiation part to the suburbs, intermediates, and far parts, so that the light that has passed through the primary lens and the secondary lens is reflected in the shape of the reflection sheet. Can also light the light from the light emitting surface of the lighting device.
According to a sixth aspect of the present invention, the surface of the energizing copper foil provided to supply electricity to the LED is widened, and the heat transferred from the solder contacts of the LED is balanced with the energizing copper foil having excellent heat conduction. It is transmitted as conduction, and the heat radiation of the LED is radiated by the natural heat radiation or forced heat radiation with a flat plate or a three-dimensional structure by the metal heat radiation plate transmitted through the insulating material to the copper foil for energization, Deterioration can be prevented.
In addition, the “metal heat sink” is a heat sink having a flat plate or a three-dimensional structure made of, for example, aluminum, copper, silver, iron, etc., and the three-dimensional structure is a fin shape, and forms an illuminating device. Metal can also be used as a heat sink.

The present invention has the following effects.
(1) The primary lens that extends the reach of light is attached to one or more LEDs arranged side by side in a substantially vertical direction with respect to the light emitting surface of the irradiation device, so that the light from the LED is reduced in diffusion. Therefore, the reachable distance of the light becomes long, and a large illuminating device can be provided.
In addition, by using a primary lens, a point light source based on LED emission can be used as a surface light source.
Light can be irradiated as a thick light source with little light diffusion, and light can be irradiated over a large area.
LED light irradiation method is a method of directly irradiating the light emitting surface of the illuminating device, a method of irradiating after applying to the diffusion sheet in front of the light emitting surface of the illuminating device in order to reduce the light intensity difference in the direct irradiation, Alternatively, the light emitting surface of the illumination device can be projected brightly by using a method in which light is once reflected and irradiated to emit light alone or in combination.
(2) The illumination device's illumination member uses a thin front-illuminated lens to control light, eliminating the need for a parabolic curved mirror reflector and halving the thickness compared to a parabolic curved mirror reflector. It can be:
A large light emitting surface of the irradiation device can be taken. So-called LED light can be emitted from the end of the light emitting surface of the irradiation device without waste.
A method of irradiating the light emitting surface of the illuminating device directly by irradiating light from the end of the illuminating device emitting surface, and a diffusion sheet provided in front of the illuminating device emitting surface in order to reduce the difference in intensity of light in direct irradiation The light emitting surface of the lighting device can be projected brightly and largely by using a method of irradiating the light to the light, or a method of emitting light by reflecting light on a reflecting member, or a combination thereof.
(3) By attaching a primary lens that extends the reach of light to each LED as a lighting member and a secondary lens that diffuses the stretched light, the secondary lens increases the reach distance with light thickened by the primary lens. The diffusion of light occurs, and the number of LEDs can be reduced with the combined light of the two.
(4) When the secondary lens has a diffusion directionality, the light source portion can be made a straight line by setting the diffusion direction parallel to the LED arrangement direction.
Further, when the diffusion direction is set at right angles to the LED arrangement direction, the light source portion can be viewed directly, but the primary lens diffusion light source can be seen, but when the object is irradiated, it is diffused right and left in the direction perpendicular to the LED arrangement direction.
(5) When the arrangement distance between the primary lens and the secondary lens is close or in close contact, the light passing through the secondary lens is diffused due to the boundary reflection of the lens, so that the diffusion irradiation rate becomes low. However, by configuring the arrangement distance to be a constant distance considering the diffusibility of the primary lens, the light diffused by the primary lens can be diffused by the secondary lens over a wide area.
(6) Optimum diffusion can be achieved if the size of the secondary lens, that is, the lens width in the so-called diffusion direction, is a size proportional to the irradiation angle of the primary lens.
(7) Also, as a method for effectively utilizing the light reflected by the secondary lens, the transparent lens or the same material as the secondary lens is used between the primary lens and the secondary lens, and both side surfaces as viewed from the primary lens. When the illumination member is viewed from the side, it is possible to make the space between the primary lens and the secondary lens bright.
(8) As a method of irradiating the light reflected by the secondary lens again in the forward direction, a straight or parabolic mirror surface between the primary lens and the secondary lens can be used as the forward irradiation light. It can also be used.
(9) Since the irradiation member can adjust the irradiation angle with respect to the reflection member, it is possible to adjust the difference (unevenness) of the shadow generated on the light emitting surface (including the shadow difference due to the unevenness of the light emitting surface).
The shadow difference may be adjusted by adjusting the reflection angle (bending angle) of the reflecting member instead of the irradiation member.
(10) The present invention can be used for lighting devices (printing characters and cases for signboards) or lighting devices using existing fluorescent lamps.
(11) As the light emitting surface of the lighting device, one surface light emission is used as one lighting member. However, by attaching it vertically or horizontally, it is possible to cope with two continuous enlargements. By doing so, a double-sided reflection type lighting device can be obtained.
(12) The light that has passed through the primary lens and the secondary lens is light that travels straight and diffuses, so that depending on the reach distance to the reflecting surface, the intensity of light at the time of arrival, and the irradiation angle, By providing the three-stage reflection angle of the suburbs, the middle part, and the far part, the light that has passed through the primary lens and the secondary lens can be lit brightly from the light emitting surface of the irradiation device even from the shape of the reflection sheet.
(13) By transmitting the heat generated by the LED to the copper foil surface for energization, which is excellent in the thermal conductivity of the size of the primary lens, contact transmission as a wide heat source to the metal heat sink that is in close contact with the insulating material As a result, the performance and life of the LED can be fully exploited. Therefore, it is possible to cope with higher LED brightness (high current type LED = high power LED), and it is possible to improve the brightness of illumination.
(14) The insulated copper foil heat radiating plate and the housing (case) of the lighting structure are insulated and joined, whereby the case (case) can be radiated to the outside as a heat radiating plate.
(15) Since no light guide plate (acrylic 5 mmt plate) is used, the weight can be reduced and the cost of the light guide plate can be reduced.
(16) Construction is easy (initial cost reduction).

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram showing the structure of an LED lighting device according to the present invention.
FIG. 1A shows a basic structure. The illuminating device 10 using an LED as a light source includes an irradiation member 20 disposed inside a side surface 12 formed in a direction substantially perpendicular to the light emitting surface 11 of the illuminating device 10, and light emitted from the irradiation member 20. By providing the reflecting member 60 that is bent to the right, the light emitting surface shines with no shadow difference, and functions as a lighting device.
FIG. 1B shows a lighting device having light emitting surfaces on both sides with the basic structure of FIG. 1A back to back.
FIG. 1C illustrates a lighting device having a large light-emitting surface in which the basic structure of FIG.
FIG. 1D is a combination of FIG. 1B and FIG. 1C to provide a lighting device having a double-sided and large light-emitting surface.

2 and 3 are a perspective view and a cross-sectional view of an irradiation member in which a primary lens and a secondary lens are combined with an LED.
The irradiation member 20 is provided with a plurality of LEDs 30, 30,... In the longitudinal direction of the irradiation member main body 21 and a primary lens 40 and a secondary lens 50 attached to each LED 30. The primary lens 40 is a thin lens that extends the reach of the LED light, and the secondary lens 50 is a corrugated lens that diffuses the LED light. A heat radiating portion 22 is provided behind the LED 30.

FIG. 4 is an explanatory diagram showing characteristics of the primary lens or the secondary lens.
FIG. 4A is an irradiation image of an LED without a lens attached. In the case of an LED in which a convex lens is not incorporated, the light reaches a short distance, and light diffuses with a wide diffusion rate. Even if a convex lens is incorporated in the LED with a transparent resin, elongated light that does not diffuse from the light source portion can be produced, but it becomes a light source that uniformly illuminates a long range.
FIG. 4B is an irradiation image of an LED with a primary lens attached. Irradiated in the straight direction, the reach distance is dramatically increased by thick irradiation light.
FIG. 4C is an irradiation image of an LED with a secondary lens attached. The arrival distance of light is almost the same as in the case of FIG. 4A, but the light diffuses in a wave line shape. (Distance diagram of LED and secondary lens is omitted)
FIG. 4D is an irradiation image of an LED to which a primary lens and a secondary lens are attached. Although it does not reach the reach of the light in FIG. 4B, diffusion occurs simultaneously with the straight light that does not exist in the light of FIG.
Widely long light can be obtained by continuously arranging the light in the diffusion direction.

FIG. 5 is an explanatory diagram showing the effect of the primary lens or the secondary lens.
FIG. 5A is a cross-sectional view of a light source in the horizontal direction of the light of the LED to which the primary lens and the secondary lens are attached, and FIG. 5B is the light of the LED to which only the secondary lens is attached. It is sectional drawing which looked directly at the light source of the horizontal direction. According to this, a surface light source having a large luminous flux is generated by the primary lens, and this is diffused in the short direction by the secondary lens. Compared to FIG. 5B with only the secondary lens, it is found that a large irradiation area is generated with a small number of LEDs. Therefore, by combining the primary lens and the secondary lens, the LED can be efficiently used (stretched / diffused).

FIG. 6 is an explanatory view showing a reflecting member.
The reflecting member 60 shown in FIG. 6 is a reflecting member having a curved surface, and is divided into a suburb portion (a), an intermediate portion (b), and a far portion (c) according to the distance from the irradiation member 20. The section “a” is formed as a straight section, the section “b” is formed as a gentle curve section, and the section “c” is formed as a steep curve section. In this way, by changing the reflecting surface of the reflecting member 60 in accordance with the distance from the irradiation member 20, the light that has passed through the primary lens and the secondary lens becomes brighter than the light emitting surface 11 of the lighting device 10. Can emit light. In particular, even when the light emitting surface 11 has irregularities, a uniform amount of light is supplied to the light emitting surface 11 from behind, so that a good light emitting surface free from unevenness (shade) can be provided.

FIG. 7 shows illuminance data and an illuminance graph obtained by actually measuring the light emitting surface of the illumination device.
<Measurement conditions>
・ Measurement position: 10 mm position from the light emitting surface ・ Measurement place: Nine locations on the light emitting surface were measured (the average value was calculated)
Illumination member: Side surface inner side formed in a direction substantially perpendicular to the light emitting surface <Each Example>
-Example 1: No reflecting member-Example 2: An aluminum specular reflector as a reflecting member is installed in a slanting straight line in the lighting device (see FIG. 1A).
-Example 3: A white reflective sheet is installed as a reflective member in a slanting straight line in the lighting device (see FIG. 1A).
-Example 4: A white reflective sheet is installed in the lighting device as a reflective member in an obliquely curved shape (see FIG. 6).
<Conclusion>
In the lighting device of the present application, a diagonal surface reflection method (installed in an oblique straight line) using a reflection sheet or mirror is provided, but by using the curved surface reflection method (FIG. 6), the reflection performance equivalent to this diagonal surface reflection method is provided. It was confirmed that the

Although this invention can be utilized for the following as an illuminating device provided with the light emission surface, it is not limited to this.
(1) Signboard (2) Indicator light (3) Information board (4) Other

The conceptual diagram which shows the structure of LED lighting apparatus. The perspective view of the irradiation member which combined the primary lens and the secondary lens with LED. Sectional drawing of the irradiation member which combined the primary lens and the secondary lens with LED. Explanatory drawing which shows the characteristic of a primary lens or a secondary lens. Explanatory drawing which shows the effect of a primary lens or a secondary lens. Explanatory drawing which shows a reflection member. Illuminance data and illuminance graph obtained by actually measuring the light emitting surface of the lighting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Illuminating device 11 Light emission surface 12 Side surface 20 Irradiation member 21 Irradiation member main body 22 Radiating part 30 LED
40 Primary lens 50 Secondary lens 60 Reflective member

Claims (6)

An illumination device using an LED as a light source,
An irradiation member disposed inside the side surface formed in a direction substantially perpendicular to the light emitting surface of the lighting device;
A reflection member that bends light from the irradiation member to the light emitting surface;
The irradiation member is provided with a plurality of LEDs in the longitudinal direction of the side surface, and a primary lens for extending a light reaching distance is attached to each LED.   2. The LED illumination device according to claim 1, wherein a thin forward illumination lens is attached as a primary lens in order to reduce the size and thickness of the illumination member installed in the illumination device.   The irradiation member is provided with a plurality of LEDs in the longitudinal direction of the side surface, and a primary lens for extending the reach of light and a secondary lens for diffusing the extended light are attached to each LED. LED lighting apparatus of description.   The LED illumination device according to claim 1, wherein the irradiation member is capable of adjusting an irradiation angle with respect to the reflection member.   5. The LED illumination according to claim 1, wherein the reflecting member is a reflecting resin sheet or a specular plate, and reflects the diffusing light and the straightly traveling light at a reaching point by a linear surface or a curved surface. apparatus. 6. The LED illumination device according to claim 1, 2, 3, 4, or 5, wherein the irradiating member is configured to dissipate a width and a length of the energizing copper foil as heat conduction for conducting heat emitted from the LED.

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