JPH0643425A - Illuminator - Google Patents

Abstract

PURPOSE:To provide an illuminator in which a light guiding body and a circuit board on which a discharge lamp an lighting circuit parts are coupled integrally, a wiring and handling are facilitated, and a particular space is eliminated. CONSTITUTION:A low voltage discharging lamp 4 is allowed to pass through the insert-through hole 3 formed in a light guiding body 1. light radiated from the discharging lamp 4 is allowed to conduct through the inside of the light guiding body 1 so as to be emitted from one side face of the light guiding body 1, lighting circuit parts 11-14 for lighting the discharge lamp 4 are installed on a circuit board 10 and on the circuit board 10, an engaging part 15 is formed and the detaining part 15 is engaged with the discharge lamp 4 or the light guiding body 1 and the circuit board 10, the low voltage discharge lamp 4 and the light guiding body 1 are coupled integrally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device used as a backlight of a liquid crystal display device.

[0002]

2. Description of the Related Art Liquid crystal display instrument panels, liquid crystal display televisions, and the like emit light from the back surface of a liquid crystal plate. As such a back lighting device, one using a light guide is known. ing. That is, in the conventional case, a plate-shaped or block-shaped light guide made of a light transmissive material having a milky white light diffusing action such as acrylic resin is arranged on the back surface of the liquid crystal plate, and one end surface of this light guide is arranged. Outside the light guide body facing the, for example, a straight tube type hot cathode or cold cathode type fluorescent lamp is provided, and the light emitted from the lamp is introduced into the light guide body from the end face of the light guide body. The light guide is diffused and emitted from one side surface, for example, the upper surface.

However, when the lamp is arranged outside the light guide, the light emitted from the lamp is emitted in the radiation direction of the straight tube bulb, so that the amount of light directed to the light guide is reduced, which is prevented. Therefore, the surroundings of the lamp are surrounded by a reflector, and an aperture type fluorescent lamp is used. However, as described above, the light emitted from the lamp is reflected by the reflecting mirror and directed toward the light guide,
Even if a device such as an aperture fluorescent lamp is used as the light source, a gap is created between the lamp and the light guide and leaks to the outside through this gap, and reflection loss occurs due to the light-shielding film or reflection film surrounding the lamp. The effective utilization rate of the light emitted from the lamp has not always been sufficient due to causes such as generation and reflection on the end surface of the light guide.

Under these circumstances, there has been proposed an illuminating device in which an insertion hole is formed in the light guide and a low-pressure discharge lamp is inserted through the insertion hole. According to this, the light emitted from the low-pressure discharge lamp penetrating the light guide body is directly and entirely incident on the light guide body surrounding the entire circumference in the circumferential direction, causing leakage to the outside and reflection loss. Therefore, the effective utilization rate of light is increased. Further, since the discharge lamp is inserted into the insertion hole, there is an advantage that the entire structure is compact.

[0005]

However, in the case of such a configuration, there is a problem in dealing with the circuit parts for starting and lighting the low pressure discharge lamp. For example, high frequency lighting circuit components include components such as electrolytic capacitors and transistors, and in many cases these components are mounted on a circuit board.

However, in the conventional case, the circuit board on which the above-mentioned lighting circuit parts are mounted is separated from the light guide body and attached to a chassis or the like which supports the light guide body and the liquid crystal plate. There are problems such as complicated wiring connections and the need for a special space for mounting the circuit board on the chassis, which makes the chassis larger.

Further, since the light guide and the circuit board are separated,
There is also a drawback that it is troublesome to handle. The present invention is to provide a lighting device in which a light guide, a discharge lamp, and a circuit board on which a lighting circuit component is mounted are integrally coupled to facilitate wiring and handling, and a special space is not required. is there.

[0008]

In order to achieve the above-mentioned object, the first object of the present invention is to penetrate a low pressure discharge lamp through an insertion hole formed in a light guide and guide the light emitted from this discharge lamp to the above-mentioned. A lighting circuit component for lighting the discharge lamp is mounted on a circuit board so that the light guide body is electrically connected and emitted from one side surface of the light guide body, and a locking portion is formed on the circuit board. Is locked to the protruding portion of the discharge lamp protruding from the light guide, whereby the circuit board, the low-pressure discharge lamp, and the light guide are integrally coupled.

The second aspect of the present invention is that the low-pressure discharge lamp penetrates through an insertion hole formed in the light guide body, and the light emitted from the discharge lamp is conducted through the light guide body to allow the light guide body to pass through. By attaching a lighting circuit component that emits light from one side and lighting the discharge lamp to a circuit board, forming a locking portion on the circuit board, and locking the locking portion to the light guide body. The circuit board, the low-pressure discharge lamp, and the light guide body are integrally connected.

[0010]

In both the first and second aspects of the invention, since the engaging portion provided on the circuit board on which the lighting circuit components are mounted engages with the lamp or the light guide, the lamp and the light guide are originally integrated. As a result, the circuit board, the lamp, and the light guide body are integrated to facilitate wiring and handling. Furthermore, no special circuit board installation space is required.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on a first embodiment shown in FIGS. 1 and 2 for a lighting device used in a liquid crystal display device.

In FIG. 1, reference numeral 1 denotes a light guide member which is arranged so as to face a back surface of a liquid crystal display plate (not shown). This light guide member 1 is made of a milky white light diffusing and transmitting material such as acrylic resin. It is formed in a plate shape or a block shape. The light guide 1 is surrounded by a casing 2 or a reflective coating except on one side surface, that is, the upper surface, and the inner surface of the casing 2 or the reflective coating is a reflective surface.

The light guide 1 is provided with, for example, two through holes 3 and 3. These insertion holes 3 and 3 are parallel to each other and penetrate horizontally. That is, the insertion holes 3 and 3 are parallel to the upper surface of the light guide 1.

A low-pressure discharge lamp as a light source, for example, a straight-tube cold-cathode fluorescent lamp 4, 4 is penetrated through these insertion holes 3, 3. Each of these cold cathode fluorescent lamps 4 and 4 has a cold tube not shown sealed at both ends of a straight tube type bulb, and lead wires 5 and 5 connected to the cold cathode are led out from the end faces. A phosphor coating (not shown) is formed on the inner surface of the bulb, and a predetermined amount of mercury and a rare gas are enclosed in the bulb. The straight-tube cold-cathode fluorescent lamps 4 and 4 are inserted into the insertion holes 3 and 3 with their ends projecting outside the light guide 1.

A circuit board 10 is attached to the lower surface of the light guide 1 in an overlapping manner. The circuit board 10 is formed to be longer than the length of the light guide body 1, and high frequency lighting circuit components are mounted on the extension portions of both ends protruding from the end portion of the light guide body 1. This high frequency lighting circuit component is, for example, an electrolytic capacitor 1
1, the transformer 12, the fuse 13, the condenser 14, etc. In the present embodiment, since the two lamps 4 and 4 are used and the respective lamps are individually lit, the high frequency lighting circuit component is Two sets are provided and are collectively arranged on the upper surface of the end portion of the circuit board 10. Further, the lead wires 5 and 5 led out from the end portions of the fluorescent lamps 4 and 4 protruding from the end portions of the light guide body 1.
Are electrically connected to the circuit board 10.

The circuit board 10 is provided with four sets of locking parts, for example, locking claws 15 so as to face the ends of the lamps 4 and 4, respectively. These locking claws 15 are engaged with the lamps 4 and 4 by gripping the ends of the lamps 4 and 4 protruding from the ends of the light guide 1 as shown in FIG. 2B. It is supposed to stop.

Therefore, the circuit board 10 is locked to the lamps 4 and 4 via the locking claws 15 ... In other words, the circuit board 10 is suspended by the locking claws 15 ... Since the fluorescent lamps 4 and 4 penetrate the light guide 1 and are coupled to the light guide 1, when the circuit board 10 is locked to the lamps 4 and 4 via the locking claws 15 ... The circuit board 10 is connected to the light guide 1 via the lamp 4, and eventually the circuit board 10, the lamp 4 and the light guide 1 are integrally connected. In this case, the circuit board 10
Are overlapped and coupled to the lower surface of the light guide 1.

On the circuit board 10, the ends of the fluorescent lamps 4 and 4 protruding from the end of the light guide body 1 and the high frequency lighting circuit parts 11 and 1 mounted on the ends of the circuit board 10.
Separation walls 16 ... Are erected between the two, 13, and 14. These isolation walls 16 are for thermally insulating the end portions of the fluorescent lamps 4 and 4 from the high frequency lighting circuit components 11, 12, 13, and 14. The operation of the embodiment having such a configuration will be described.

When the fluorescent lamps 4, 4 are turned on, these lamps 4, 4 emit light in the radiation direction of the bulb. The light emitted from these lamps 4 and 4 enters the light guide 1 through the inner surfaces of the through holes 3 and 3 that surround the light.

In this case, the lamps 4 and 4 are surrounded by the light guide 1.
All light emitted in the radiation direction is surrounded by the light guide 1.
to go into. Therefore, the light does not leak to the outside and the reflection loss does not occur before entering the light guide body 1, and the effective utilization rate of the light increases.

The light thus entering the light guide body 1 is diffused inside the light guide body 1 by the light diffusion action of the light guide body 1,
After being reflected by the casing 2 surrounding the light guide 1 or the reflective surface coating, the light is emitted from the upper surface to the outside. Therefore, the back surface of the liquid crystal display panel is illuminated.

The lighting circuit components 11 to 14 for keeping the fluorescent lamp 4 lit are mounted on the ends of the circuit board 10, and the circuit board 10 is superposed on the light guide 1 and integrally connected. Therefore, the lamps 4 and 4 inserted in the light guide 1 come close to the lighting circuit parts, and the wiring of the lamp is easy. In addition, the light guide 1 and the lamps 4 and 4
Since the three members, the circuit board 10 and the circuit board 10, are integrated, they can be handled easily.

In this case, the locking claw 1 provided on the circuit board 10
5 is hooked on the end of the lamp 4 to connect the circuit board 10 to the lamp 4, and as a result, the light guide 1, the lamps 4 and 4, and the circuit board 10 are integrated, so that the structure is simple. is there.

When the lamps 4 and 4 are inserted into the light guide 1, the ends of the lamps need to be projected from the ends of the light guide 1 because the ends where the electrodes are sealed serve as heat generating parts. Therefore, the end portion of the light guide 1 needs a space for protruding the end portion of the lamp. Lighting circuit parts 11 to 1
4 are collectively mounted on the end portion of the circuit board 10 and the lighting circuit components 11 to 14 are arranged in the above space. Therefore, the lighting device does not become large and another special space is required. Disappear.

In the case of the present embodiment, the high-frequency lighting circuit parts 11 to 11 mounted on the ends of the fluorescent lamps 4 and 4 protruding from the end of the light guide body 1 and the end of the circuit board 10.
Since the isolation wall 16 is provided between the lighting circuit parts 11 and 14, the ends of the lamp 4 that generate heat during lighting are shut off and the lighting circuit parts 11 to 14 are thermally damaged. Absent. Further, the isolation walls 16 ... Also function as a heat dissipation wall and prevent the temperature from rising.

In the above embodiment, the locking claws 15 formed on the circuit board 10 are hooked on the ends of the lamp 4, but the locking formed on the circuit board 10 as shown in FIG. The claws 20 ... May be locked to the end of the light guide 1. Even in this way, the light guide 1 and the lamps 4, 4 are
Also, the three members of the circuit board 10 can be integrally combined, and other effects similar to those of the embodiment of FIG. 1 are obtained. The present invention is not limited to the use of the two straight tube fluorescent lamps 4 and 4, and a bent lamp 40 having a U shape as shown in FIG. 4 may be used. Furthermore, the lamp is not limited to a cold cathode fluorescent lamp, and may be a hot cathode type and may be a rare gas discharge lamp such as a xenon lamp.

[0027]

As described above in detail, in both the first and second aspects of the present invention, the locking portion provided on the circuit board on which the lighting circuit component is mounted is locked to the lamp or the light guide. Since the lamp and the light guide are originally integrated, the circuit board, the lamp, and the light guide are integrated, so that the lamp and the lighting circuit component are arranged close to each other. It is easy to handle and it is easy to handle because the whole is unitized. Furthermore, since no special installation space for the circuit board is required, the size and size can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view of a lighting device according to a first embodiment of the present invention.

FIG. 2A is a plan view of the same embodiment, and FIG. 2B is a view taken along line II-II in FIG.

FIG. 3A is a plan view of an illuminating device according to a second embodiment of the present invention, and FIG. 3B is a view taken along the line III-III in FIG. 3A.

FIG. 4 is a plan view of an illumination device according to a third embodiment of the present invention.

[Explanation of symbols]

1 ... Light guide, 3 ... Insertion hole, 4, 40 ... Fluorescent lamp, 1
0 ... Circuit board, 11-14 ... Lighting circuit parts, 15, 20
… Locking claws, 16… Isolation wall.

Claims (2)

[Claims] 1. A light guide body having an insertion hole formed therein, a low pressure discharge lamp passing through the insertion hole, and the light emitted from the discharge lamp is conducted through the light guide body to one side surface of the light guide body. The lighting circuit component for lighting the discharge lamp is mounted on a circuit board, and a locking portion is formed on the circuit board, and the locking portion of the discharge lamp protruding from the light guide body. An illuminating device characterized in that the circuit board, the low-pressure discharge lamp and the light guide body are integrally connected to each other by being locked to a protrusion. 2. An insertion hole is formed in the light guide, a low pressure discharge lamp is penetrated through the insertion hole, and light emitted from the discharge lamp is conducted through the light guide to one side surface of the light guide. The lighting circuit component for lighting the discharge lamp is mounted on a circuit board, and a locking portion is formed on the circuit board. The locking portion is locked to the light guide body to form a circuit board. An illumination device, wherein the low-pressure discharge lamp and the light guide body are integrally connected.