TW201804185A - Display device and refrigerator having the same capable of increasing the light use efficiency - Google Patents

Abstract

The invention relates to a display device capable of increasing the light use efficiency and a refrigerator having the display device. The display device includes a display panel, a light guide plate disposed behind the display panel, a light emitting means configured to emit light into the light guide plate, and a substrate disposed behind the display panel and provided with a detection part configured to detect a change of capacitance. The light guide plate includes light extraction parts configured to irradiate light that is light-guided in the light guide plate. The number of the light extraction parts disposed at the side of the display panel is larger than the number of the light extraction parts disposed at the side of the substrate.

Description

Display device and refrigerator provided with the same

The present invention relates to a display device and a refrigerator including the same.

Increasingly, display devices using a light guide plate are used in home appliances such as refrigerators, microwave ovens, and portable devices. A light guide plate is a plate that guides light incident from the side of a transparent plate such as acrylic, polystyrene, etc., to total light under the law of Esnael to guide the light, while taking out the light formed on the surface The part scatters part of the light and emits light. In addition, the display device is configured such that a character, a mark print, or a light-shielding film is arranged on the surface side of the light guide plate, and the character or the like is irradiated with light from a light source. As such a prior art aspect of using a display device under a light guide plate, for example, there is Patent Document 1.

Patent Document 1 relates to a storage room including a refrigerator main body, a storage room door that opens and closes a front opening of the storage room, a light-transmitting door front surface plate on a front surface of the storage room door, a substrate on a back surface of the door front surface plate, and a substrate. The display structure between the door and the front panel, the illumination means for illuminating the display structure toward the front surface of the door, the detection unit that detects the change in capacitance behind the display structure, and the guidance Light board, inspection The control unit that controls the measurement unit and the illumination means is configured on the substrate by the illumination means and the detection unit, and the detection unit adopts a mutual capacitance type.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2015-55361

However, in the technology described in Patent Document 1, the entire light guide plate emits light, and the film disposed on the light guide plate is not only a display portion (light transmitting portion) corresponding to characters, but a large amount of light is irradiated to the non-text characters. Such a light-shielding portion (non-light-transmitting portion) is absorbed by the light-shielding portion, so that there is such a problem that the utilization efficiency of light is low. In addition, there are problems such as deformation and shaking of the light guide plate, which reduces the sensitivity of the touch panel, or light leaks toward the substrate side at the contact portion.

Therefore, an object of the present invention is to provide a display device or a refrigerator provided with the display device, in which the display device maintains the sensitivity of the touch panel and improves the light utilization efficiency.

A display device includes a display panel, a light guide plate located behind the display panel, and a light emitting hand that makes light enter the light guide plate. A substrate provided with a detection unit that detects a change in capacitance is mounted behind the display panel. The light guide plate includes a light extraction portion that emits light guided by the light guide plate, and the light extraction portion. The display panel side of the light guide plate is formed more than the substrate side of the light guide plate.

According to the present invention, a display device or a refrigerator provided with the display device can be provided. The display device can maintain the sensitivity of the touch panel while improving the light utilization efficiency.

1‧‧‧ refrigerator main body

2a‧‧‧Left refrigerator door

2b‧‧‧Right refrigerator door

2d‧‧‧Freezer

3‧‧‧Upper hinge

3a‧‧‧left hinge

3a, 3b‧‧‧Right hinge

3b, 4a‧‧‧ Ice door

4b‧‧‧Freezer door

4b, 4c‧‧‧‧Freezer door

4d1‧‧‧Freezer

4d2‧‧‧Quick Freezer

4d3‧‧‧‧Ice-making Chamber

5‧‧‧Vegetable room door

5d‧‧‧Vegetable Room

6‧‧‧Door front panel (glass panel)

9‧‧‧ Operation display area

9a‧‧‧ Display touch unit

10‧‧‧ display area

11‧‧‧LED

12‧‧‧light extraction section

13‧‧‧light guide

14‧‧‧Display section (light transmitting section)

15‧‧‧Non-light transmitting section

16‧‧‧display board (film)

17‧‧‧ substrate

18‧‧‧ touch sensor

[FIG. 1] A front view of a refrigerator according to an embodiment of the present invention.

[Fig. 2] Fig. 2 is a diagram illustrating display states of a display area and an operation display area of the P portion shown in Fig. 1.

3 is a front view of a state where a film is removed from a display device according to the present embodiment.

[FIG. 4] A cross-sectional view of an operation display area in FIG. 2. [FIG.

FIG. 5 is a diagram showing a result obtained by calculating an illuminance distribution of a conventional display unit.

FIG. 6 is a diagram showing a result obtained by calculating an illuminance distribution of a display unit according to this embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

The following description is based on a refrigerator in which a display device according to the present invention is built in a storage room door.

FIG. 1 is a front view of a refrigerator according to this embodiment, and is a view in which a display portion and an operation portion are in a non-display state. The refrigerator main body 1 includes a refrigerator compartment 2d, a freezer compartment 4d1, a vegetable compartment 5d, and the like in this order from the top. Between the refrigerating compartment 2d and the freezing compartment 4d1, a rapid freezing compartment 4d2 is provided, and an ice-making compartment 4d3 is provided next to the rapid freezing compartment 4d2.

Moreover, the front opening of each storage room is provided with the door which opens and closes the said front opening. That is, the front opening of the refrigerating compartment 2d is provided with a left refrigerating compartment door 2a and a right refrigerating compartment door 2b, and the freezer compartment 4d1, the quick freezing compartment 4d2, the ice-making compartment 4d3, and the vegetable compartment 5d are individually opened in front. A freezing compartment door 4b, a quick freezing compartment door 4c, an ice-making compartment door 4a, and a vegetable compartment door 5 are respectively provided.

The left refrigerator compartment door 2a and the right refrigerator compartment door 2b are pivoted freely through the upper hinge 3 (left hinge 3a, right hinge 3b) and the like provided on the upper part of the refrigerator main body 1, respectively. That is, the structure is a so-called French door which is configured as a left-right type.

In addition, the freezing compartment door 4b, the quick freezing compartment door 4c, the ice-making compartment door 4a, and the vegetable compartment door 5 are draw-out doors, respectively, and can be freely drawn out together with the container of the individual storage compartment.

The left refrigerator compartment door 2a and the right refrigerator compartment door 2b The door 4b, the quick freezing compartment door 4c, the ice-making compartment door 4a, and the vegetable compartment door 5 are provided on their outer surfaces with a door front surface plate (glass plate) 6 having transparency.

Next, the operation display area 9 serving as both the operation area and the display area is operated by the user from outside to set the room temperature of each of the storage compartments such as the refrigerating compartment 2d and the freezing compartment 4d1, or the refrigerating compartment 2d and the freezing compartment 4d1. Wait for rapid cooling, or set the operation of the ice making device on / off, rapid ice making, etc. That is, the user operates the operation display area 9 so that the functions of the refrigerator can be set.

In addition, the display area 10 displays a result of the input from the operation display area 9. Through this display area 10, the operation performed by the user in operating the display area 9 can be confirmed, or the status of various functions set in advance can be confirmed.

Furthermore, the display touch section 9a for turning on the operation display area 9 and the display area 10 is operated, so that the operation display area 9 and the display area 10 are switched from the light-off state of FIG. 1 to the state of FIG. 2. Lighting status. That is, the user performs operations such as pressing, touching, and bringing his or her finger close to the display touch portion 9a (as an example of a “MENU” text display mark), so that operations other than the display touch portion 9a that is always recognizable are performed. The characters, symbols, and the like in the display area 9 and the display area 10 are switched from the light-off state to the light-on state, and are displayed on the glass plate 6 to operate the display area 9. Thereby, the display of characters and graphics that are usually recognizable at all times is only the display touch portion 9a, and the non-lighting operation of the display area 9 and the display area 10 can make a simple appearance and improve the design sense. this In addition, the display area 9 and the display area 10 only need to be turned on when the display area 10 is operated, so energy saving effects can be obtained.

In addition, when the display touch unit 9a is operated, all characters, graphics, and the like in the operation display area 9 and the display area 10 are illuminated and displayed. After the certain period of time has elapsed, the display area 10 is turned on only for the display of the setting status of the functions currently set, and other displays are turned off. In addition, when a certain period of time has passed in the non-operation state, all characters, graphics, and the like in the operation display area 9 and the display area 10 are turned off, and only the display touch portion 9a becomes visible. In this way, after the display touch unit 9a that is always visible is operated, all the characters and the like are temporarily turned on, so that the user can confirm the functions of the refrigerator and confirm what settings can be changed.

The back surface of the glass plate 6 is coated with a colored paint. Thereby, the processing is performed so that the foamed heat insulation material is not seen from the front side, and the operation display area 9 and the display area 10 are clearly recognized by the operation of the display touch portion 9a, so that a door having excellent appearance can be realized.

FIG. 3 is a front view in a state where the film is removed from the display device, and FIG. 4 is a cross-sectional view at a place where the display area 9 is operated in FIG. 2. The display device corresponding to this operation display area 9 includes a display panel (film) 16 having a display portion (light transmitting portion) 14 and a non-light transmitting portion 15, a light guide plate 13 located behind the display plate 16, and The LED 11 that emits visible light into the light-emitting means in the light guide plate 13 and the substrate 17 on which the control circuit is provided. The light guide plate 13 includes a light extraction portion 12 that emits light guided in the light guide plate 13.

Here, the display portion 14 is constituted by characters or symbols having translucency, and the non-light-transmitting portion 15 is formed on the periphery of the display portion 14. In addition, a voltage is applied to the LEDs 11 arranged on the left and right sides of the light guide plate 13 formed of an acrylic material, so that the light emitted from the LED 11 enters from the side of the light guide plate 13 and is totally reflected to repeatedly guide the light inside the light guide plate 13. . When the light reaches the light extraction portion 12 formed on the surface of the light guide plate 13, the light is emitted therefrom. In addition, placing the LED 11 and the light guide plate 13 not in the front-back direction of the substrate 17 but in the left-right direction of the substrate 17 makes it possible to reduce the overall thickness of the display device, and to increase the foam insulation of the back side of the display device. Material thickness to ensure thermal insulation performance.

The light extraction portion 12 is provided behind or near the display portion 14 as shown in FIG. 4, and is provided more than other regions (non-transmissive portion 15), so that the non-transmissive portion 15 is suppressed from being irradiated and non-transmissive. The light absorbed by the light portion 15 can efficiently irradiate the light guided in the light guide plate 13 to the display portion 14, and can improve the visibility of characters, symbols, and the like.

In addition, it is more effective to provide a plurality of light extraction portions 12 in FIG. 4 than to the rear surface (substrate side) of the light guide plate 13 on the front surface (display plate side) of the light guide plate 13. This is because the light emitted from the light extraction portion 12 on the back of the light guide plate 13 can be suppressed from being absorbed by the substrate 17, and the light reflected by the substrate 17 in various directions can be absorbed by the non-light-transmitting portion 15 of the display plate 16.

Further, among the light guide plates 13 formed to be long in the left-right direction, the density of the light extraction portion 12 on the center side is higher than the density of the light extraction portions 12 on the left and right end sides. The center here is the line on the light guide plate 13 farthest from the left and right LEDs 11. For this reason, even in In the vicinity of the center far from the LED 11 where light is difficult to reach, a sufficient amount of light can still be emitted, and unevenness in brightness in the left and right directions can be appropriately adjusted.

In addition, the light extraction portion 12 in FIG. 4 has a convex shape on the front surface and the rear surface of the light guide plate 13, but it is not necessarily limited to a convex shape, and may be a concave shape. Among them, the light extraction portion 12 on the back side of the light guide plate 13 is more effective in terms of convex shape than concave shape. The height of the convex light extraction region 12b in the center of the back surface of the light guide plate 13 is more effective than the height of the peripheral light extraction region. The convex light extraction portion 12 is preferably a polygonal pyramid, a cone, or the like having a hexagonal pyramid or the like, rather than a polygonal pillar. The reason is that the convex light extraction portion 12 on the back of the light guide plate 13 is in point contact with the substrate 17 near the center of the light guide plate 13, so that the touch sensor 18 caused by the deformation and shaking of the light guide plate 13 can be suppressed on one side. The sensitivity is reduced, and light leakage to the substrate 17 side is suppressed.

The light extraction portion 12 on the back side is preferably formed in the range from the center of the light guide plate 13 to 2/3 of the LED 11. More preferably, it is effective that the light extraction region 12 is formed in a range from the center of the light guide plate 13 to 1/2 of the LED 11. The reason is that the convex light extraction portion 12 on the back of the light guide plate 13 is formed near the center of the light guide plate 13 so that the sensitivity of the touch sensor 18 caused by the deformation and shaking of the light guide plate 13 can be suppressed while reducing the sensitivity. Light leakage to the substrate 17 is suppressed.

In addition, the two light extraction portions 12 on the substrate 17 side and the left and right centers are each further formed by one or both of the density and height of the light extraction region 12b on the center side, and are formed to be higher than the light extraction regions 12a on both sides thereof. . The reason is that by this, the light extraction efficiency in the center of the display section is improved The text's legibility improves.

In addition, the light extraction portion 12 may be another manufacturing method capable of performing concave-convex processing such as laser processing, metal mold forming, and sandblasting. In addition, the light extraction portion 12 in FIG. 4 can also be printed with a resin containing a scattering material for visible light. When the light guided through the total reflection in the light guide plate 13 reaches the scattering material, the light is scattered and can be efficiently irradiated to characters, signs, and the like.

The side surface of the light guide plate 13 is flat. Thereby, the light incident from the LED 11 is totally reflected on the end surface of the light guide plate 13 to prevent light leakage, and at the same time, the light guided by the light guide plate 13 is efficiently irradiated to the display portion 14 and the visibility of characters and the like Promotion. In addition, the side surface (end surface) of the light guide plate is formed by cutting an acrylic plate into a desired shape, and performing mirror polishing as a final polishing. The manufacturing method may be particularly limited as long as the side surface is transparent.

The surface of the substrate 17 on the back side of the light guide plate 13 is printed with a silk-colored ink. With this, although most of the light emitted toward the substrate is reflected on the substrate and then emitted in the light extraction portion of the display panel, the light can be efficiently irradiated to the display portion 14 to improve visibility of characters and the like.

FIG. 5 shows the illuminance distribution of the display portion 14 of the light guide plate having a conventional structure, and FIG. 6 shows the illuminance distribution of the display portion 14 when the light guide plate 13 of the light extraction portion 12 is applied in this embodiment. Painter. For the calculation method, optical simulation is used. That is, the optical characteristics of the LED manufactured by the LED manufacturer, the structure of the light extraction portion and the light guide plate, and the material characteristics are set in simulation, and the orbit of the light incident from the LED is simulated. The trace is calculated using a light guide plate having a conventional structure and the structure of this embodiment, and the distribution of light emitted toward the display surface side is evaluated.

As a result, in this embodiment, the brightness of the two sides of the light guide plate 13 does not change much compared with the conventional structure; on the other hand, the brightness of the center of the light guide plate 13 is improved to improve uneven brightness. The reason will be described below. It is estimated that the reason is that in the conventional structure, the darkest system is near the center of the light guide plate 13, and in this embodiment, the number of the light extraction portions 12 is increased near the left and right centers of the substrate side of the light guide plate 13 than in other areas. Therefore, most of the light emitted toward the substrate side is reflected on the substrate 17, and then the light is emitted on the light extraction portion 12 on the display panel 16 side. In addition, it is estimated that the reason is that the two light extraction portions 12 on the substrate 17 side and the left and right centers have the density and height of the light extraction area 12b on the center side higher than the light extraction areas 12a on both sides, so the display is displayed. The efficiency of the light extraction portion 12 at the center of the plate 16 is improved.

In addition, in the display section manufactured through this embodiment, the brightness of each display section can be made uniform while suppressing the reduction of the sensitivity of the touch panel caused by the deformation and shaking of the light guide plate.

Based on the above, according to this embodiment, it is confirmed that a display device can be provided, which can maintain the sensitivity of the touch panel, improve the light utilization efficiency, and increase the brightness of the central display portion 14.

In addition, the present invention is not limited to a refrigerator having a display device built into a storage room door, and is also effective for other household appliances and industrial products with a display device such as an air cleaner, a washing machine, and an IH cooking heater. In addition, the light source is not only LED, but also cold cathode fluorescent tube, organic EL, inorganic EL, phosphors, other illuminants. In addition, in the light guide plate, it is effective to use acrylic resin, polycarbonate, polystyrene, etc., which have high transmittance to visible light.

11‧‧‧LED

12‧‧‧light extraction section

12a, 12b‧‧‧‧light extraction area

13‧‧‧light guide

14‧‧‧Display section (light transmitting section)

15‧‧‧Non-light transmitting section

16‧‧‧display board (film)

17‧‧‧ substrate

18‧‧‧ touch sensor

Claims (8)

A display device includes a display panel, a light guide plate located behind the display panel, a light-emitting means for causing light to enter the light guide plate, and a substrate having a detection unit for detecting a change in capacitance provided behind the display panel, The light guide plate has a light extraction portion that emits light that guides light in the light guide plate, and the light extraction portion is formed on the display plate side of the light guide plate more than the substrate side of the light guide plate. . For example, the display device according to the first patent application range, wherein the light emitting means is located at a side of the light guide plate and a density of the light extraction portion at a center side is higher than a density of the light extraction portion at both end sides. For example, the display device according to claim 1 or 2, wherein the light extraction portion on the substrate side is convex, and the height in the center is higher than the height in the periphery. For example, the display device according to item 1 or 2 of the patent application scope, wherein the light extraction portion having a convex shape is formed on the substrate side of the light guide plate in a range from the center of the light guide plate to 2/3 of the light emitting means. . For example, the display device according to claim 3 or 4, wherein the convex light extraction portion is formed to have one or both of a density and a height of the light extraction region on the central side. For example, the display device according to any one of claims 1 to 5, wherein: The display panel has a light-transmitting portion and a non-light-transmitting portion, and the light extraction portion is formed more than the back of the light-transmitting portion than the back of the non-light-transmitting portion. For example, the display device according to any one of claims 1 to 6, wherein the light guide plate has a flat side surface. A refrigerator includes a storage room door that opens and closes a front opening of the storage room, and a heat insulating material in the storage room door, and further includes a display device as set forth in any one of claims 1 to 7.