JP7765240B2 - Light source device and liquid crystal display device - Google Patents

Description

This disclosure relates to a light source device and a liquid crystal display device.

For example, Patent Document 1 discloses a backlight device having a light-transmitting diffusion plate and a housing in which a light source is mounted. In this backlight device, a pin provided on the bottom of the housing maintains the distance between the light-transmitting diffusion plate and the bottom of the housing, preventing the light-transmitting diffusion plate from sagging toward the bottom of the housing.

Japanese Patent Application Laid-Open No. 2004-186080

In the backlight device of Patent Document 1, for example, when an LED substrate, which is an LED formed on a substrate, is used as a light source, there is a risk that an IC chip provided on the side opposite to the light emitting side of the LED substrate may come into contact with other components such as the backlight chassis, causing damage to the LED substrate. In order to prevent this damage to the LED substrate, it is conceivable to provide a spacer between the LED substrate and the backlight chassis, but this can lead to problems such as an increase in the number of parts, an increase in work hours, and an increase in costs.
A main object of the present disclosure is to provide a light source device that can reduce the number of parts and prevent damage to the LED substrate.

A light source device according to one embodiment of the present disclosure includes an optical sheet, an LED board having LEDs provided on a surface facing the optical sheet, a chassis supporting the optical sheet and the LED board, a support member having a support section that maintains a distance between the optical sheet and the LED board, a spacer section that maintains a distance between the LED board and the chassis, and a connection section that connects the support section and the spacer section, the support member being inserted into a through hole provided in the LED board, the support section protruding toward the surface of the LED board on which the LEDs are provided, and the spacer section protruding toward the surface of the LED board opposite the surface on which the LEDs are provided.

1 is a perspective view of a liquid crystal display device according to a first embodiment. FIG. 2 is a cross-sectional view of a main part of a backlight in the liquid crystal display device of the first embodiment. FIG. 3 is a schematic perspective view showing a state in which a support member is fixed to the substrate in FIG. 2. FIG. 10 is a cross-sectional view of a main part of a backlight according to a modified example.

Embodiments of the present disclosure will be described below with reference to the drawings. Note that in the drawings, identical or equivalent elements will be given the same reference numerals, and duplicate explanations will be omitted. Furthermore, the embodiments described below are merely examples of the present disclosure, and the present disclosure is not limited to these embodiments. Various modifications other than these embodiments may be made depending on the design, etc., as long as they do not deviate from the technical concept of the present disclosure.

First Embodiment
FIG. 1 is a perspective view of a liquid crystal display device 1 according to this embodiment.

The liquid crystal display device 1 includes a liquid crystal panel 10 and a backlight (light source device) 20.

In the liquid crystal display device 1, light from the backlight 20 is irradiated onto the back surface of the liquid crystal panel 10, and the incident light is modulated and transmitted through the liquid crystal panel 10 to display an image on the front surface of the liquid crystal panel 10.

The backlight 20 will be described in more detail below. Figure 2 is a cross-sectional view of a main portion of the backlight 20. Figure 3 is a perspective view schematically showing the support member 60 fixed to the LED board 40 in the backlight 20 of Figure 2.

As shown in FIG. 2, the backlight 20 includes, for example, an optical sheet 30, an LED substrate 40, and a backlight chassis (chassis) 50. In the liquid crystal display device 1, the liquid crystal panel 10 is disposed on the optical sheet 30 side of the backlight 20. The backlight 20 then irradiates light emitted from LEDs mounted on the LED (Light Emitting Diode) substrate 40 onto the liquid crystal panel 10 via the optical sheet 30.

The optical sheet 30 includes, for example, a light-transmitting diffusion plate, which transmits light emitted from the LEDs on the LED board 40 and uniformly irradiates the liquid crystal panel 10.

The LED substrate 40 has multiple LEDs arranged on it. These LEDs are provided on the surface of the LED substrate 40 facing the optical sheet 30. Furthermore, an LED lens 41 is provided on each of the light-emitting surfaces of the multiple LEDs.

On the other hand, multiple IC chips 42 are provided on the surface of the LED board 40 opposite the surface on which the LEDs are arranged. The IC chips 42 control multiple LEDs. Therefore, the surface of the LED board 40 on which the IC chips 42 are provided has a relatively larger area that can come into contact with the LED board 40 without causing any problems compared to the surface on which the LEDs are formed.

The backlight chassis 50 is, for example, a housing with an opening that holds the optical sheet 30 and supports the LED board 40 so that it faces the optical sheet 30.

In addition, the support member 60 is fixed to the LED board 40 in the backlight 20 by being inserted into the through-hole 43 provided in the LED board 40. The support member 60 maintains the distance between the optical sheet 30 and the LED board 40, and the distance between the LED board 40 and the backlight chassis 50.

The support member 60 has a support portion 61 that maintains the distance between the optical sheet 30 and the LED board 40, a spacer portion 64 that maintains the distance between the LED board 40 and the backlight chassis 50, and a connection portion 67 that connects the support portion 61 and the spacer portion 64. The support member 60 is inserted into a through hole 43 provided in the LED board 40, with the support portion 61 protruding toward the side of the LED board 40 on which the LEDs are provided, and the spacer portion 64 protruding toward the side of the LED board 40 opposite the side on which the LEDs are provided. In the support member 60, at least one support portion 61 is connected to one spacer portion 64.

More specifically, the support member 60 includes, for example, a support portion 61, a spacer portion 64, and a connection portion 67 that connects the support portion 61 and the spacer portion 64.

The support portion 61 includes, for example, a tip portion 62 and a bottom portion 63. The tip portion 62 is smaller than the diameter of the through-hole 43 and contacts the optical sheet 30. The bottom portion 63 is larger than the diameter of the through-hole 43 and contacts the surface of the LED substrate 40 on which the LEDs are mounted. That is, the support portion 61 is at least partially wider than the diameter of the through-hole 43. This allows the portion of the support portion 61 wider than the diameter of the through-hole 43 to deflect inward when a force is applied from the outside. This support portion 61 maintains the distance between the optical sheet 30 and the LED substrate 40, suppressing deflection of the optical sheet 30 and preventing contact of the optical sheet 30 with the LED lens 41, thereby preventing damage to the LED lens 41. The shape of the support portion 61 is, for example, conical or polygonal pyramidal. This prevents blocking of light incident on the optical sheet 30 from the LEDs. The inside of the bottom portion 63 is hollow. The lower end 63 bends inward when an external force is applied inward from the outside, and returns to its original shape when the external force is released.

The spacer portion 64 includes, for example, a peripheral edge portion 65. The peripheral edge portion 65 is larger than the diameter of the through-hole 43 in the spacer portion 64. The width of the spacer portion 64 is at least partially wider than the diameter of the through-hole 43. The thickness of the spacer portion 64 is also thicker than the thickness of the IC (Integrated Circuit) chip 42. The spacer portion 64, particularly the peripheral edge portion 65, maintains the distance between the LED board 40 and the backlight chassis 50, preventing contact between the IC chip 42 and the backlight chassis 50 even in the event of vibration.

The connection portion 67 includes, for example, a first connection portion 68 and a second connection portion 69.

The first connection portion 68 connects the tip portion 62 and the spacer portion 64, for example, by penetrating the cavity in the lower end portion 63. The first connection portion 68 maintains the connection between the support member 60 and the spacer portion 64 between the optical sheet 30 and the backlight chassis 50, and mainly maintains the distance between the support portion 61 and the spacer portion 64.

The second connection portion 69 connects the lower end portion 63 and the spacer portion 64. It is preferable that the second connection portion 69 partially contacts the inner wall of the through-hole 43 when the support member 60 is fixed to the LED board 40. This prevents the support member 60 from moving radially through the through-hole 43.

With the configuration of this embodiment, the distance between the optical sheet 30 and the LED board 40, and the distance between the LED board 40 and the backlight chassis 50 can be maintained by the support member 60. In other words, with the configuration of this embodiment, simply providing the support member 60 eliminates the need to provide separate spacers or the like between the optical sheet 30 and the LED board 40, and between the LED board 40 and the backlight chassis 50. This reduces the number of parts and the number of manufacturing processes, enabling cost savings.

Next, we will explain how to attach the support member 60 to the LED board 40.

The tip 62 of the support member 60 is inserted and pushed into the through-hole 43 from the side of the LED board 40 where no LEDs are provided. This secures and attaches the support member 60 to the LED board 40. When the support member 60 is pushed in, the lower end 63 is pushed inward by the inner wall of the through-hole 43, causing it to deform, then passes through the through-hole 43 and returns to its original shape after passing through the through-hole 43. This sandwiches the LED board 40 between the underside of the lower end 63 and the peripheral edge 65 of the spacer portion 64, allowing the support member 60 to be secured to the LED board 40.

In addition, in the backlight 20, the spacer portion 64 may or may not be in contact with the backlight chassis 50. For example, if the spacer portion 64 is in contact with the backlight chassis 50, the support member 60 will be less likely to come off the LED board 40. Furthermore, for example, if the spacer portion 64 is not in contact with the backlight chassis 50, chattering between the support member 60 and the backlight chassis 50 can be suppressed, and the spacer portion 64 can be prevented from pushing up the LED board 40.

Furthermore, in the backlight 20, the spacer portion 64 may be fixed to the backlight chassis 50 with an adhesive material such as double-sided tape. This makes it possible to easily assemble the LED board 40 and the backlight chassis 50 without using fixing materials such as screws.

When manufacturing the backlight 20, the support member 60 may be attached to the LED substrate 40, and then the backlight chassis 50 and optical sheet 30 may be attached. Alternatively, the support member 60 may be attached to the backlight chassis 50 with an adhesive such as double-sided tape, and then the LED substrate 40 and optical sheet 30 may be attached in that order.

Now, we will further explain a modified backlight. Figure 4 is a cross-sectional view of a main part of a modified backlight 201. In the modified backlight 201, the support member 60 in the above-described backlight 20 has been replaced with a support member 601.

As shown in FIG. 4 , the support member 601 has a configuration in which multiple support portions 61 are connected to spacer portions 641. More specifically, multiple pairs of support portions 61 and connection portions 67 are connected to the spacer portions 641. Furthermore, the spacer portions 641 correspond to areas of the LED board 40 where no IC chips 42 are formed. In other words, when the support member 601 is fixed to the LED board 40, the spacer portions 641 avoid the IC chips 42 provided on the LED board 40. This allows multiple support portions 61 to be installed simply by attaching the support member 601 to the LED board 40, preventing contact between the IC chips 42 and the backlight chassis 50 and improving work efficiency.

Note that while the light source device described above is used as a backlight for a liquid crystal display device, this is not limiting and the light source device may also be, for example, a lighting device.

The present disclosure is not limited to the above-described embodiments, and may be replaced with a configuration that is substantially the same as the configuration shown in the above-described embodiments, a configuration that provides the same effects, or a configuration that can achieve the same purpose.

1 Liquid crystal display device, 10 Liquid crystal panel, 20 Backlight (light source device), 30 Optical sheet, 40 LED substrate, 41 LED lens, 42 IC chip, 43 Through hole, 50 Backlight chassis (chassis), 60/601 Support member, 61 Support portion, 64/641 Spacer portion, 67 Connection portion

Claims (5)

an optical sheet;
an LED substrate having an LED provided on a surface facing the optical sheet;
a chassis supporting the optical sheet and the LED substrate;
a support member including a support portion for maintaining a distance between the optical sheet and the LED substrate, a spacer portion for maintaining a distance between the LED substrate and the chassis, and a connection portion for connecting the support portion and the spacer portion;
Equipped with
The support member is inserted into a through hole provided in the LED substrate, the support portion protruding toward a surface of the LED substrate on which the LEDs are provided, and the spacer portion protruding toward a surface of the LED substrate opposite to the surface on which the LEDs are provided,
the spacer portion and the support portion are at least partially wider than the diameter of the through hole;
A light source device, wherein a portion of the support part having a width greater than the diameter of the through hole bends inward when a force is applied from outside . The light source device described in claim 1, wherein the LED substrate has an IC chip on the surface opposite to the surface on which the LEDs are provided. The light source device described in claim 1 or 2, wherein the support member has multiple support portions connected to one spacer portion. The light source device according to claim 1 , further comprising an adhesive member that bonds the spacer portion and the chassis together. A liquid crystal display device comprising a liquid crystal panel and the light source device according to any one of claims 1 to 4 .