KR20200136865A - Display device - Google Patents

Abstract

The present invention relates to a display device that includes: a display panel displaying an image; an acoustic element which provides sound; and a rear chassis accommodating the display panel to protect a rear surface of the display panel, wherein the acoustic element is attached to the rear chassis, and at least one open portion is located around the acoustic element. According to the present invention, sound can be generated without installing a separate speaker, or touch or motion detection is possible without the addition of a separate touch panel/touch sensor.

Description

Display device {DISPLAY DEVICE}

The present invention relates to a display device and, in addition to displaying an image, relates to a display device that generates sound or vibration.

The display device developed from the conventional cathode ray tube (CRT) method using a cathode ray tube, and developed a liquid crystal display (LCD), plasma display panel (PDP), organic light emitting display (OLED), electrowetting display (EWD), and electrophoretic (EPD) display), an embedded microcavity display (EMD), and a nano crystal display (NCD) have been developed.

Among these flat panel displays, a liquid crystal display (LCD), which is in the spotlight in recent years, has advantages such as miniaturization, weight reduction, and low power consumption, so it can overcome the shortcomings of conventional cathode ray tubes (CRT). It has gradually attracted attention as an alternative means of being used, and is now installed and used in almost all information processing devices that require a display device. In a liquid crystal display, a liquid crystal material is generally injected between an upper substrate on which a common electrode and a color filter are formed, and a lower substrate on which a thin film transistor and a pixel electrode are formed, and the pixel electrode and the common electrode are It is a device that forms an electric field by applying a different electric potential to change the arrangement of liquid crystal molecules, thereby controlling the transmittance of light to express an image.

In a liquid crystal display device, a liquid crystal display panel is a light receiving element that does not emit light by itself, and thus a backlight unit is provided under the liquid crystal display panel to provide light to the liquid crystal display panel.

Meanwhile, among flat panel displays, an organic light-emitting display device has an advantage of not using a backlight including a light-emitting diode that emits light by itself.

However, all of these display devices have only a function of displaying an image, and a separate speaker must be installed to provide sound.

In addition, a touch-sensing display device is also widely used. In order to detect a touch or motion, a panel including a touch sensor must be additionally formed or a touch sensor must be formed in the display device, resulting in additional cost.

The technical problem to be achieved by the present invention is to provide a display device capable of generating a sound without installing a separate speaker or capable of detecting a touch or motion without adding a separate touch panel/touch sensor.

In order to solve this problem, a display device according to an embodiment of the present invention includes a display panel that displays an image; An acoustic element that provides sound; And a rear chassis accommodating the display panel to protect a rear surface of the display panel, wherein the acoustic element is attached to the rear chassis, and at least one open portion is positioned around the acoustic element.

The at least one open part may be located on the rear chassis.

The space between the acoustic element and the rear chassis may serve as a ringtone.

The rear chassis may partition the space.

The rear chassis may have a protruding area corresponding to the space.

The at least one open part may be located adjacent to the protruding area.

The at least one open portion may be disposed parallel to an edge of the protruding region.

The protruding region and the acoustic element may correspond one-to-one.

The acoustic element may be located within the protruding region.

It provides sound and further includes another acoustic element attached to the rear chassis, wherein the rear chassis has another protruding region, and the another acoustic element may be located within the another protruding region.

The protruding region and the other protruding region may be connected to each other.

Another acoustic element that provides sound and is attached to the rear chassis may be further included, and the acoustic element and the another acoustic element may be located in the same protruding area.

The display panel may be an organic light emitting display panel.

The acoustic device may include a pair of electrodes and a vibrating material layer interposed therebetween.

An adhesive for attaching the acoustic element and the rear chassis may be further included, and the adhesive may include a non-conductive epoxy.

The display panel includes a substrate, a printed circuit board, and a flexible circuit board, the substrate of the display panel is connected to the printed circuit board through the flexible circuit board, and an amplifier may be formed on the printed circuit board. have.

The vibrating material layer of the acoustic element may also generate vibration at a frequency other than the audible frequency, and detect a change in a frequency other than the audible frequency to detect a user's touch, thereby implementing a haptic function.

The acoustic device may perform pressure sensing using a voltage generated by external pressure.

The display device may further include a microphone, and a vibration of a frequency other than an audible frequency emitted from the acoustic element may be modulated according to a Doppler effect according to a user's motion, and then sensed by the microphone to detect a user's motion.

A battery for supplying power to the display device may be further included, and a voltage generated when the acoustic element vibrates may be transmitted to the battery to charge the battery.

The number of acoustic elements may be two or more.

The two or more acoustic elements may be located in a space positioned between the acoustic element and the rear chassis.

As described above, a piezo material (for example, a material such as PVDF or PZT) that provides sound by applying an electric field is formed to provide sound from the display device. In addition, when a user touches using a vibration rather than an audible frequency, a separate touch screen may not be formed because the user can receive feedback and sense the touch. In addition, since the movement of the hand around the display device can be sensed by the Doppler effect, a separate motion sensor may not be included.

1 is a cross-sectional view of a display device according to an exemplary embodiment of the present invention.
2 is a rear view of a display device according to an exemplary embodiment of the present invention.
3 and 4 are rear views of a display device according to still another exemplary embodiment of the present invention.
5 to 10 are graphs showing characteristics of a display device according to an exemplary embodiment of the present invention.
11 is a photograph of vibration characteristics of a display device according to an exemplary embodiment of the present invention.
12 to 18 are diagrams illustrating various exemplary embodiments of a display device according to an exemplary embodiment of the present invention.
19 to 22 are diagrams showing structures of various acoustic devices according to an embodiment of the present invention.
23 and 24 are diagrams illustrating an amplifier in a display device according to an exemplary embodiment of the present invention.
25 to 29 are diagrams illustrating driving characteristics usable by a display device according to an exemplary embodiment of the present invention.

An embodiment of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

In the drawings, the thicknesses are enlarged to clearly express various layers and regions. The same reference numerals are assigned to similar parts throughout the specification. When a part of a layer, film, region, plate, etc. is said to be "on" another part, this includes not only the case where the other part is "directly above", but also the case where there is another part in the middle. Conversely, when one part is "directly above" another part, it means that there is no other part in the middle.

Now, a display device according to an exemplary embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

1 is a cross-sectional view of a display device according to an exemplary embodiment of the present invention, and FIG. 2 is a rear view of a display device according to an exemplary embodiment of the present invention.

The display device according to the exemplary embodiment of the present invention accommodates and protects the display panel 70 and the display panel 70, and includes a rear chassis 28 having a protruding area 28-1, and a protruding area 28- It includes an acoustic element 27 located in 1).

The display panel 70 in the exemplary embodiment of FIG. 1 may be a display panel that emits light by itself or a light-receiving display panel that receives light from a light source and displays an image. A display panel that emits light by itself includes an organic light-emitting display panel, and a light-receiving display panel includes a liquid crystal display panel. The light-receiving display panel may include a backlight unit.

The display panel 70 includes a TFT substrate made of a plurality of TFTs (thin film transistors), and the TFT substrate is a transparent insulating substrate on which a matrix-shaped thin film transistor is formed, and a data line is connected to a source terminal, A gate line is connected to the gate terminal. In addition, a pixel electrode made of transparent ITO (indium tin oxide) as a conductive material may be connected to the drain terminal. The detailed structure of the display panel 70 may vary according to the type and embodiment of the display panel.

The display panel 70 of FIG. 1 may be a display panel assembly. That is, the display panel 70 of FIG. 1 is an assembly including a display panel and includes an integrated circuit chip (IC chip) and a flexible printed circuit board (FPC) in addition to the display panel. It may further include a driving unit to drive.

The data line and the gate line of the display panel 70 are connected to the flexible circuit board, and when an electric signal is input from the flexible circuit board, the electric signal is transmitted to the source terminal and the gate terminal of the TFT. The TFT is turned on or off according to the scanning signal applied to the terminal, and the image signal applied to the source terminal through the data line is transmitted or blocked to the drain terminal. The flexible circuit board receives an image signal from the outside of the display panel and applies a driving signal to the data line and the gate line of the display panel, respectively.

The flexible circuit board generates an image signal and a scan signal, which are signals for driving the display device 100, and a plurality of timing signals for applying these signals at an appropriate time, and transmits the image signal and the scan signal to the display panel 70. Is applied to the gate line and the data line respectively. In addition, in the flexible circuit board according to an embodiment of the present invention, an amplifier (refer to FIG. 23) for amplifying and transmitting sound signals may be formed. The amplifier receives the sound signal received from the outside, amplifies it, and transmits the sound signal to the sound element 27 through sound signal wiring.

The display panel 70 may further include a mold frame, and the display panel may be fixed by the mold frame. In addition, a top chassis may be further included to prevent separation of the display panel 70 in the front direction.

A rear chassis 28 is included to protect the rear surface of the display panel 70. The rear chassis 28 may be referred to as a bottom chassis or a back chassis, and serves to accommodate and protect the display panel 70 while being positioned on the rear surface of the display panel 70. The rear chassis 28 may be combined with a mold frame or a top chassis of the display panel 70 to protect the display panel 70 in some embodiments.

The rear chassis 28 according to the embodiment of the present invention includes a protruding region 28-1 protruding in the rear direction. The extent and extent of the protrusion of the protruding region 28-1 in FIG. 1 are shown enlarged, and the extent of the actual protrusion may not be easily recognized by the naked eye.

The protruding region 28-1 is an area where the acoustic element 27 is located, and may serve as a ringtone for amplifying sound provided from the acoustic element 27.

An acoustic element 27 is attached to the inner surface of the protruding region 28-1 of the rear chassis 28 by an adhesive 51. As the adhesive 51, an adhesive including non-conductive epoxy may be used. In this case, heat may be applied to dry the adhesive 51 or natural drying may be performed. When heat is applied to the acoustic element 27, characteristics of the vibrating material layer 27-1 may be deteriorated. This was confirmed by the results of the reliability test. Accordingly, in the case of attaching the acoustic element 27, natural drying can be performed even if it takes time. However, if the sound quality provided by the acoustic element 27 is not important (for example, a receiver that provides the other party's voice from a telephone), it may be dried by applying heat.

The acoustic element 27 includes a pair of electrodes 27-2 and a vibrating material layer 27-1 interposed therebetween. The vibrating material layer 27-1 includes a piezo material that vibrates by an electric field provided from a pair of electrodes 27-2 positioned up and down, and examples of the piezo material include PVDF (Poly Vinylidene Fluoride). And PZT (zircon titanium shovel lead ceramic).

PVDF contains PVDF-TrFE (polyvinylidene fluoride trifluoroethylene), and has material properties that are easy to manufacture in a flexible film form. On the other hand, compared to PVDF, PZT is difficult to weave in a film form, so it is difficult to have flexible characteristics. However, depending on the embodiment, PZT and PVDF (or PVDF-TrFE) may be mixed and used to form a film while using PZT as a vibrating material layer.

Meanwhile, the pair of electrodes 27-2 are positioned on both sides of the vibrating material layer 27-1, respectively, and provide an electric field to the vibrating material layer 27-1. The electrode 27-2 may use various conductive materials such as transparent conductors such as ITO and IZO, opaque metals, conducting polymers, and carbon nanotubes (CNT).

The acoustic element 27 is attached to the inner surface of the protruding region 28-1 of the rear chassis 28 and vibrates. Due to the vibration of the acoustic element 27, the protruding region 28-1 also vibrates, and as a result, the entire rear chassis 28 vibrates and the vibration is transmitted to the display panel 70 as well. Since this is determined according to the material of the rear chassis 28 and the magnitude of vibration provided from the acoustic element 27, a problem may not occur if the vibration of the actual acoustic element 27 is relatively small. In order to eliminate the risk of a problem occurring due to the vibration provided by the acoustic element 27, an open portion positioned along the boundary of the protruding region 28-1 around the protruding region 28-1 of the rear chassis 28 ( 28-2) is formed. The open part 28-2 not only serves to buffer the vibration of the acoustic element 27 to be transmitted to the rear chassis 28 as it is, but also serves to faithfully serve as a ringer when the protruding area 28-1 vibrates. It also serves to improve the movable range of the protruding region 28-1 so that it is possible. In addition, sound is discharged to the outside through the open part 28-2, so that the user can easily hear the sound.

The open portion 28-2 has a structure parallel to a part of the boundary of the protruding area 28-1, and its length and width have various structures according to embodiments. The adjacent open portions 28-2 are also arranged at regular intervals.

Referring to FIG. 2, the open portion 28-2 is located within the protruding region 28-1, but may be located outside the protruding region 28-1 in some embodiments.

Referring to FIG. 2, the protruding region 28-1 has a circular structure, and a wiring connection part 28-3 extending linearly is formed at one end of the circular structure. The wiring connection portion 28-3 is a portion in which an acoustic signal wiring for transmitting an acoustic signal transmitted from the amplifier to the acoustic element 27 is connected into the protruding region 28-1. The wiring connection part 28-3 may protrude to the same extent as the protrusion region 28-1, and may have a smaller degree of protrusion than that according to embodiments.

Meanwhile, in some embodiments, a window made of tempered glass or plastic may be disposed on the front surface of the display panel 70. The window prevents the front surface of the display panel 70 from being damaged from the outside. The window 30 may constitute an outer surface of a display side of a portable electronic device such as a mobile phone or other electronic device.

Although the embodiment of FIG. 1 shows an embodiment in which one acoustic element 27 is included, the number of the acoustic elements 27 may include a plurality of two or more.

Hereinafter, another embodiment of the present invention will be described with reference to FIGS. 3 and 4.

3 and 4 are rear views of a display device according to still another exemplary embodiment of the present invention.

3 and 4, unlike the embodiment of FIG. 2, the presence or absence and location of the open part 28-2 are different.

First, look at the embodiment of FIG. 3.

The display device 100 according to the exemplary embodiment of FIG. 3 has a protruding area 28-1 and a wiring connection 28-3 on the rear chassis 28, but does not include the open portion 28-2. This is an example.

Meanwhile, the display device 100 according to the exemplary embodiment of FIG. 4 has a protruding area 28-1, an open portion 28-2, and a wiring connection 28-3 in the rear chassis 28, but FIG. 2 Unlike the embodiment of, the open portion 28-2 is located outside the protruding region 28-1. The open part 28-2 is parallel to the boundary of the protruding area 28-1, as in the embodiment of FIG. 2, and the length and width may be variously formed according to the embodiment.

Hereinafter, acoustic characteristics of the display device 100 according to an exemplary embodiment of the present invention will be described through FIGS. 5 to 11.

First, the vibration characteristics at a specific position of the rear chassis 28 will be described through FIGS. 5 to 10.

5 illustrates a measurement location for measuring acoustic characteristics of the display device 100 and a location of an acoustic element according to an embodiment of the present invention.

As illustrated in FIG. 5, in the display device 100 of the embodiment for testing the acoustic characteristics, an embodiment including two acoustic devices (speakers) is used. That is, it is the position of 1 and 2 of FIG. 5, and two acoustic elements are located inside the protruding area 28-1 of the rear chassis 28.

The rear chassis 28 is in a state in which the triangle shown in Fig. 5 is fixed, and Fig. 5 shows an embodiment as shown in Fig. 3 in which there is no open part 28-2 near the protruding region 28-1. , In the experiment, an embodiment (e1_base) as shown in FIG. 3 without an open portion 28-2, and an embodiment (e1_slit) as shown in FIG. 2 in which the open portion 28-2 is inside the protruding region 28-1. In) and the open portion 28-2 were measured using an example (e1_slit out) as shown in FIG. 4 in which the protruding region 28-1 is outside.

In addition, positions at which acoustic characteristics are measured are positions 1 to 5 in FIG. 5, and acoustic characteristics at each position are illustrated in FIGS. 6 to 10.

In the embodiment of FIG. 6, the acoustic characteristics at the position 1 are shown as a graph, in FIG. 7 the acoustic characteristics at the position 2 are shown, and in FIG. 8, the acoustic characteristics at the position 3 are shown, and FIG. 9 shows the acoustic characteristics at the 4th position, and FIG. 10 shows the acoustic characteristics at the 5th position. The graphs of FIGS. 6 to 10 show the stiffness of the rear chassis against frequency, and the smaller the stiffness is, the more advantageous it is to amplify the sound.

6 to 10, it can be seen that the present embodiment has better sound amplification effect than the embodiment without the open part 28-2. In the low frequency region of 1 kHz or less and the high frequency region of 3 kHz or more, the open part 28- The embodiment in which 2) is located outside the protruding region 28-1 has a good sound amplification effect, and in the intermediate frequency region in between, the open part 28-2 is located inside the protruding region 28-1. In this example, the sound amplification effect was good.

On the other hand, in Fig. 11, the embodiment as in Fig. 3 without the open part 28-2 (No slit), the embodiment as in Fig. 2 in which the open part 28-2 is inside the protruding region 28-1. Figure 4 shows the result of photographing the vibration characteristics at each frequency after the (slit in) and the open part (28-2) vibrate the embodiment (slit out) as shown in FIG. 4 outside the protruding region (28-1). Are doing.

According to FIG. 11, in the embodiment without the open part 28-2 as shown in FIG. 3, vibrations caused by the acoustic element 27 spread widely to the entire area of the rear chassis 28 so that the entire rear chassis 28 vibrates. It can be confirmed that it has characteristics.

In addition, in the low frequency range of 200 to 1 kHz (low sound) and the high frequency range of 8k to 9 kHz (high sound), the embodiment of FIG. 4 in which the open portion 28-2 is located outside the protruding area 28-1 has a sound amplification effect. It can be seen that the sound amplification effect is good in the embodiment of FIG. 2 in which the open part 28-2 is located inside the protruding region 28-1 in the midtone region of 1.3k~2.7kHz. .

Therefore, not only can the position of the open part 28-2 be adjusted according to the frequency characteristics of the mainly used sound, but also the open part 28-2 can be formed both inside and outside the protruding area 28-1. have.

Hereinafter, various exemplary embodiments according to changes in the number, position, and shape of the acoustic element 27 and the protruding region 28-1 will be described through FIGS. 12 to 18.

First, in FIG. 12, various modified examples of the protruding region 28-1 in the rear chassis 28 will be described.

12 shows various shapes of the protruding region 28-1. In FIG. 2, a protruding region 28-1 protruding in a cylindrical shape except for the wiring connection part 28-3 is shown, but in FIG. 12, the protruding region 28-1 excluding the wiring connection part 28-3. Shows various shapes of.

In addition to the circular shape of the rear surface, the protruding region 28-1 has various shapes such as an oval shape or a square shape with rounded corners. Unlike the illustration, it may have a quadrangular structure with an angled corner, a polygonal structure with rounded corners, and an angled polygonal structure.

One acoustic element 27 may be formed in the protruding region 28-1, but two or more acoustic elements 27 may be formed as shown in FIG. 5. When one acoustic element 27 is positioned, it may be positioned in the center of the protruding area 28-1.

In FIG. 12, an embodiment in which two protruding regions 28-1 of the same size are formed on the rear chassis 28 at regular intervals is also shown, and an exemplary embodiment in which two protruding regions 28-1 of different sizes are formed. Is shown. At least one acoustic element 27 may be positioned in each protruding region 28-1, and the acoustic element 27 may be positioned at the center of the protruding region 28-1.

In addition, in FIG. 12, a protruding region 28-1 having a shape in which the two protruding regions 28-1 overlap is shown. That is, a structure in which two different circular protruding regions 28-1 are arranged to overlap some regions to form one protruding region 28-1 is also shown. At least one acoustic element 27 may be positioned in the protruding region 28-1. When two acoustic elements 27 are located, one protruding area 28-1 is virtually divided into two circular protruding areas so that the two acoustic elements 27 are respectively located in the center of each circle. have.

The shape of the protruding region 28-1 shown in FIG. 12 is a representation of some examples of various embodiments, and the embodiment of the present invention is not limited to the protruding region 28-1 of FIG. 12.

13 shows a more specific structure of the rear chassis 28 including the open portion 28-2 and the wiring connection portion 28-3 based on the circular protruding region 28-1. Various embodiments are illustrated in FIG. 13 according to the location of the open portion 28-2 and the number of protruding regions 28-1. In the embodiment of Fig. 13, an embodiment in which the acoustic elements 27 are two is shown.

First, an embodiment having one protruding region 28-1 will be described. Two acoustic elements 27 are provided in one protruding region 28-1, and one wiring connection 28-3 is formed corresponding to the one protruding region 28-1. In this case, the position of the open portion 28-2 is outside the protruding region 28-1 in one embodiment, and the inside of the protruding region 28-1 in another embodiment. Depending on the embodiment, the open portion 28-2 may not be included.

Meanwhile, in an embodiment in which two protruding regions 28-1 are formed, one acoustic element 27 is positioned in each protruding region 28-1. The acoustic element 27 may be located in the center of the protruding region 28-1. Each protruding region 28-1 has one wiring connection 28-3. In this case, the position of the open portion 28-2 is outside the protruding region 28-1 in one embodiment, and the inside of the protruding region 28-1 in another embodiment. Depending on the embodiment, the open portion 28-2 may not be included.

In FIG. 13, two acoustic elements 27 are shown. If the two acoustic elements 27 are used, stereo sound can be provided to the user.

In the embodiment of FIG. 13, only a circular structure is used among the protruding regions 28-1 of various shapes of FIG. 12, and thus more embodiments can be formed by merging with the embodiment of FIG. 12. Modifications not shown in FIGS. 12 and 13 may also be included in the scope of the present invention.

In FIGS. 14 to 18, various embodiments are shown centering on an embodiment in which the cushion tape 70-1 is used instead of the rear chassis 28. In the embodiments of FIGS. 14 to 18, the rear chassis 28 may be included in a display panel (or display panel assembly) indicated by 70. That is, the cushion tape 70-1 may be located on the rear surface of the rear chassis 28, or alternatively, the additional rear chassis 28 may be located on the rear surface of the cushion tape 70-1. In addition, in FIGS. 14 to 18, there may be an embodiment in which the window 30 is formed on the front surface of the display panel 70, and this is illustrated by a dotted line. The window 30 is not a component that must be included, and is formed of tempered glass or plastic to prevent damage to the front surface of the display panel 70 from the outside. The window 30 may constitute an outer surface of a display side of a portable electronic device such as a mobile phone or other electronic device.

First, an embodiment of FIG. 14 will be described.

The display device 100 according to the exemplary embodiment of the present invention covers the display panel 70, the acoustic element 27 positioned on the rear surface of the display panel 70, and the rear surface of the display panel 70 and the acoustic element 27. It includes a cushion tape 70-1. Depending on the embodiment, the window 30 may be included on the front surface of the display panel 70 or the display panel assembly 70.

The cushion tape 70-1 serves to protect the back surface of the display panel 70 and the acoustic element 27. The cushion tape 70-1 may be formed of a material having elasticity, and may have a black color in which light is blocked.

As shown in FIG. 14, the cushion tape 70-1 covering the acoustic element 27 has a certain space formed around the acoustic element 27, so that it can serve as a resonator for resonating the sound of the acoustic element 27. have.

In some embodiments, number 70 of FIG. 14 may represent a display panel assembly other than a display panel. That is, the display panel 70 of FIG. 14 is an assembly including a display panel and includes an integrated circuit chip (IC chip) and a flexible printed circuit board (FPC) in addition to the display panel. It may further include a driving unit to drive.

The display panel 70 or the display panel assembly in the exemplary embodiment of FIG. 14 may be a display panel that emits light by itself or a light-receiving display panel that receives light from a light source and displays an image. A display panel that emits light by itself includes an organic light-emitting display panel, and a light-receiving display panel includes a liquid crystal display panel. The light-receiving display panel may include a backlight unit.

The display panel 70 of FIG. 14 may further include a mold frame, and the display panel may be fixed by the mold frame. In addition, a top chassis may be further included to prevent separation of the display panel 70 in the front direction, and a rear chassis called a bottom chassis or a back chassis may be further included on the rear surface.

Although the embodiment of FIG. 14 shows an embodiment in which one acoustic element 27 is included, the number of the acoustic elements 27 may include a plurality of two or more.

Meanwhile, in the embodiment of FIG. 14, the rear surface of the display panel 70 and the acoustic element 27 are formed in direct contact with each other. When the rear surface of the display panel 70 is formed of a glass substrate without a separate chassis, there is a possibility that the glass substrate may be damaged due to direct contact between the acoustic element 27 and the glass substrate.

Thus, as in the embodiment of FIG. 15, a protective film 70-2 for protecting the glass substrate is formed on the rear surface of the display panel 70, and an acoustic element 27 and a cushion tape 70-1 are formed under the protective film 70-2. An embodiment to be described is also possible.

In the embodiments of FIGS. 14 and 15, the cushion tape 70-1 covers the acoustic element 27 and may have a characteristic of amplifying the sound by resonating the sound by the space generated around the acoustic element 27.

However, when the actual height of the acoustic element 27 is not high, the space with the cushion tape 70-1 may be narrow, and thus, it may be insufficient to serve as a sound box.

Hereinafter, an embodiment in which the resonant space 70-11 is formed in the cushion tape 70-1 through FIGS. 16 and 17 will be described.

As shown in FIG. 16, the acoustic element 27 is in contact with the rear surface of the display panel 70. A cushion tape 70-1 is disposed on the rear surface of the display panel 70, which is in contact with the rear surface of the display panel 70, corresponds to the acoustic element 27, and has a resonant space 70-11 recessed.

In such an embodiment, the resonant space 70-11 can be formed to have a sufficient size as necessary, so that the sound provided from the acoustic element 27 can be sufficiently amplified.

In the embodiment of FIG. 16, the acoustic element 27 may be attached to the rear surface of the display panel 70. In FIG. 17, the acoustic element 27 is a sound space 70-11 of the cushion tape 70-1. It shows an embodiment fixed within.

As shown in FIG. 17, a fixed protrusion 70-12 is formed in the sounding space 70-11 of the cushion tape 70-1, so that the acoustic element 27 is attached to the fixed protrusion 70-12. It is fixed and is fixed in the sound space 70-11 of the cushion tape 70-1. In the embodiment of FIG. 17, the cushion tape 70-1 and the fixing protrusion 70-12 may be made of the same material, but may be made of different materials and may be attached to each other with an adhesive or the like.

In the exemplary embodiment of FIG. 17, the acoustic element 27 is in contact with the rear surface of the display panel 70, but may not be attached with an adhesive, and the rear surface of the display panel 70 and the It may be tight and fixed. The fixed protrusion 70-12 serves to prevent the acoustic element 27 from changing in position even if it is not attached by an adhesive.

On the other hand, depending on the embodiment, an embodiment without a component covering the acoustic element 27 is also possible. That is, like the display device illustrated in FIG. 18, the acoustic element 27 is positioned on the rear surface of the display panel 70, and no components may be formed on the rear surface thereof.

Hereinafter, a modified example of the acoustic element 27 will be described through FIGS. 19 to 22.

19 to 22 are diagrams showing structures of various acoustic devices according to an embodiment of the present invention.

First, a look at the acoustic element 27 of FIG. 19.

19 shows a cross-section of a portion of the acoustic element 27, and includes a pair of electrodes 27-2 and a vibrating material layer 27-1 positioned therebetween. The vibrating material layer 27-1 includes a piezo material that vibrates by an electric field provided from a pair of electrodes 27-2 positioned up and down, and examples of the piezo material include PVDF (Poly Vinylidene Fluoride). And PZT (zircon titanium shovel lead ceramic).

Based on the vibrating material layer 27-1, one electrode 27-2 is located at the top, and the other electrode 27-2 is located at the bottom. In the embodiment of FIG. 19, an electrode located at the bottom A part of the vibrating material layer 27-1 rises along the side of the vibrating material layer 27-1 and is positioned 27-21 above the vibrating material layer 27-1. The upper portion constitutes the electrode pads 27-21. In order to apply an electric field to the vibrating material layer 27-1, a wire must be connected to the two electrodes 27-2. As shown in FIG. 19, the electrode pads 27-21 of the lower electrode 27-2 are on the upper side. If positioned, there is an advantage that it can be directly connected to the two electrodes from the top. As a result, even if the lower portion of the acoustic element 27 is attached with an adhesive or the like, a signal can be applied through the upper portion.

When the acoustic element 27 having the same cross-section as in FIG. 19 is viewed from above, it may be as in FIG. 20. Two electrodes 27-2 are located on the upper part of the acoustic element 27, but most of them are occupied by the electrodes 27-2 located thereon, and only a part of the electrode pad 27 of the lower electrode 27-2 is located. -21) is located, and the electrode pads 27-21 are separated from the upper electrode 27-2 at a predetermined interval. In the embodiment of FIG. 20, the electrode pads 27-21 have a rectangular structure, and an upper electrode 27-2 is positioned except for the electrode pads 27-21 of the circle. The vibrating material layer 27-1 located below it also has a circular structure, the lower electrode 27-2 has a circular structure, and the lower electrode 27-2 has a side surface of the vibrating material layer 27-1. Therefore, it is connected to the electrode pads 27-21.

As described above, the acoustic element 27 is basically provided with a pair of electrodes 27-2 positioned at the upper and lower portions of the acoustic element 27, but depending on the embodiment, one electrode may be changed to another structure.

Referring to FIG. 21, the acoustic element 27 includes an upper electrode 27-2 and a vibrating material layer 27-1 below the electrode 27-2. The rear chassis 28 is located under the vibrating material layer 27-1. The rear chassis 28 is formed of a conductive material, and at this time, the rear chassis 28 and the upper electrode 27-2 serve as a pair of electrodes to provide an electric field to the vibrating material layer 27-1. do. That is, in the embodiment of FIG. 21, when the component to which the acoustic element 27 is attached is made of a conductive material, the electrode on one side is omitted, and the corresponding component (the rear chassis 28 in FIG. 21) serves as an electrode. Also shows that you can do it. At this time, it is preferable that components that replace electrodes such as the rear chassis 28 do not receive any other electrical signals other than signals from the amplifier.

In the embodiment of FIG. 21, since the rear chassis 28 serving as a lower electrode is very wide compared to the acoustic element 27, there are many locations to connect wires, so the vibration material layer 27-1 as shown in FIGS. 19 and 20 The electrode pads 27-21 positioned on the upper side along the side may not be separately formed.

Hereinafter, a multilayered acoustic element 27 will be described through FIG. 22.

The acoustic element 27 according to the embodiment of FIG. 22 includes three vibration material layers 27-1 and a total of four electrodes 27-2. The three vibrating material layers 27-1 are arranged in a three-layer structure, and a total of four electrodes 27-2 are located on the outermost and between the three-layered vibrating material layers 27-1. . A total of four electrodes are electrically connected to each other, two each, and are alternately arranged. The electrode 27-2 positioned at the bottom and the electrode 27-2 positioned at the top receive different signals, and the electrode 27-2 positioned in the middle receives the vibration material layer 27-1. It is connected to the top electrode 27-2 or the bottom electrode 27-2 along the side. The electrode 27-2 positioned at the bottom is configured such that the electrode pad 27-21 is positioned next to the electrode 27-2 positioned at the top so that wiring can be easily connected. As a result, each vibrating material layer 27-1 vibrates and generates sound as the vibrating material layer 27-1 vibrates due to an electric field generated by the electrodes 27-2, which are in contact with each other up and down, apply different signals. In the embodiment of FIG. 22, three vibrating material layers 27-1 are present, and thus a higher sound pressure may be generated than that of the acoustic element 27 having only one.

Hereinafter, an amplifier 80 that provides a signal to the acoustic element 27 will be described with reference to FIGS. 23 and 24.

23 and 24 are diagrams illustrating an amplifier in a display device according to an exemplary embodiment of the present invention.

In the display device 100 according to the embodiment of the present invention, the amplifier 80 is positioned on the printed circuit board 78. The amplifier 80 may be located inside a signal controller (not shown) that controls image display on the display device 100 or may be formed separately. 23 and 24 show an embodiment configured separately.

The output of the amplifier 80 is transmitted to the display panel 70 along the flexible circuit board 79, and signals to the acoustic element 27 through the acoustic signal wiring 80-1 formed on the display panel 70. Is applied.

The amplifier 80 receives the sound signal received from the outside, amplifies it, and transmits the sound signal to the sound element 27 through the sound signal line 80-1.

Such an amplifier 80 can be implemented in various integrated circuit configurations, an embodiment of which is shown in FIG. 24.

The amplifier 80 includes one integrated circuit chip, and further includes a coil, a capacitor, and a resistance element around it. Referring to the structure shown in FIG. 24, one integrated circuit chip has a total of 16 input/output terminals. Each input/output terminal has one power voltage input terminal (VDD), two ground voltage input terminals (PGND, SGND), two constant voltage input terminals (SW, VBST), and four input signal terminals (IN1+, IN1-, IN2+, IN2). -), two output signal terminals (OUT+, OUT-) and four selection signal input terminals (SHDN, SCL/GAIN, SW/RW, SDA/SEL). Four input signals are amplified and converted according to the signals selected by the four selection signal input terminals and are provided to two output terminals.

The sound signal applied to the amplifier 80 is provided from the outside of the display device, and in the case of a portable terminal carried by the user, the control unit (MPU) of the portable terminal may provide the sound signal to the amplifier 80.

Hereinafter, an exemplary embodiment used in a different manner other than providing sound to a user using the acoustic element 27 will be described.

25 to 29 are diagrams illustrating driving characteristics usable by a display device according to an exemplary embodiment of the present invention.

First, in FIG. 25, it will be described that a haptic function can be used using a frequency other than an audible frequency among vibrations of the acoustic element 27.

Vibration is generated as a whole in the display device 100 by the acoustic element 27, and a low vibration, not an audible frequency, is also generated as shown in FIG. 25. Since this frequency cannot be heard by the user, sound quality is not affected even if it is used for other purposes. When the user touches the display device 100, vibrations that change when the user touches the display device 100 may be sensed to detect the touch. The detection of such a touch may be a degree of whether there is a touch or not, and may be used together with a haptic function according to an embodiment. That is, a haptic function may be implemented by detecting a change in vibration other than the audible frequency provided by the acoustic element 27 to check whether a user touches it. To this end, a sensor capable of detecting vibration of a low frequency rather than an audible frequency may be additionally provided. Implementing a haptic using the sensor is a signal controller displaying an image on the display device 100 or a portable terminal. It can be performed in the control unit (MPU).

Hereinafter, the role of the pressure sensor will be described with reference to FIG. 26.

The vibrating material layer 27-1 included in the acoustic element 27 vibrates by an electric field and generates sound. However, when the vibrating material layer 27-1 vibrates without an electric field, a voltage is generated from the vibrating material layer 27-1. When the generated voltage is sensed, it can be confirmed that displacement has occurred in the vibrating material layer 27-1, and it is possible to perform a pressure sensing role by confirming that this is a displacement generated while being pressed by pressure.

Pressure sensing using the acoustic element 27 may additionally include a sensor 85 capable of detecting a voltage generated from the acoustic element 27. However, depending on the embodiment, the structure of the amplifier 80 is changed, and the driving as the amplifier 80 and the driving as the sensor 85 are driven by time division, so that a single amplifier 80 also serves as a pressure sensor. You may.

In FIG. 27, an embodiment of detecting a movement of a user's hand using the Doppler effect is illustrated.

When a high-frequency or low-frequency sound wave rather than an audible frequency is generated from the acoustic element 27 located inside the display device 100, when the user moves a hand on the front of the display device 100, the generated sound wave is changed and carried. A sound wave is input to the microphone 130 of the terminal. As shown in FIG. 28, sound waves are transmitted to the microphone 130 as the sound pressure increases or decreases due to the dopple effect caused by the movement of the user's hand, and the fluctuation of the sound waves provided by the microphone 130 is sensed to detect the user's hand. Motion sensing to detect the movement of

In order to perform motion sensing using the acoustic element 27, the microphone 130 is necessarily required, and when the display device 100 including the acoustic element 27 is used in an electronic device including the microphone 130, Motion sensing is possible without additional configuration.

Compared to motion sensing using a camera, motion sensing according to FIG. 27 is advantageous in that image processing by the camera is unnecessary, and only sound pressure input to the microphone 130 needs to be considered.

Hereinafter, charging of the battery of the portable terminal using the acoustic element 27 will be described with reference to FIG. 29.

As shown in FIG. 26, when the vibrating material layer 27-1 included in the acoustic element 27 vibrates without an electric field, a voltage is generated from the vibrating material layer 27-1. By storing the generated voltage in the capacitor or the battery 87, the use time of the battery may be increased. Generally used portable terminals are exposed to a certain level of vibration because they are carried with them when the user moves. Therefore, when the acoustic element 27 is included, the acoustic element 27 vibrates by itself to generate a voltage, which can be transferred to the battery 87 so that the battery 87 can be charged.

In addition, when it is not possible to charge the mobile terminal, the battery 87 is charged by shaking the mobile terminal including the acoustic element 27 or touching it tens to hundreds of times with a finger. I can.

As described above, another effect of the acoustic element 27 described in FIGS. 25 to 29 may be performed together through time-division driving in the middle of the acoustic element 27 providing sound using one acoustic element 27. . In addition, a separate acoustic element 27 may be additionally formed, and the acoustic element 27 may not be connected to an amplifier, but may be connected to a separate sensor or battery to perform only a sensing operation or a battery charging operation.

In the present invention, the acoustic element 27 is described as being positioned within the display device 100, but in order to have the characteristics of FIGS. 25 to 29, the acoustic element 27 is used in the portable terminal in which the display device 100 is used. It is sufficient if it is only somewhere, and does not necessarily have to be located in the display device 100.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It belongs to the scope of rights of

100: display device 27: acoustic element
27-1: vibrating material layer 27-2: electrode
27-21: electrode pad 28: rear chassis
28-1: protruding area 28-2: open part
28-3: wiring connection 30: window
51: adhesive 70: display panel, display panel assembly
70-1: cushion tape 70-11: ringing space
70-12: fixed projection 70-2: protective film
78: printed circuit board 79: flexible circuit board
80: amplifier 80-1: sound signal wiring
85: sensor 87: battery
130: microphone

Claims (19)

A display panel that displays an image;
A first acoustic element and a second acoustic element for providing sound; And
And a rear chassis accommodating the display panel to protect the rear surface of the display panel,
The acoustic element is attached to the rear chassis,
The display device includes two or more acoustic elements. In claim 1,
The rear chassis has a protruding area. In paragraph 2,
The protruding region has a first protruding region and a second protruding region,
The first acoustic element is located in the first protruding region,
The second acoustic element is located in the second protruding area. In paragraph 3,
The first protrusion area and the second protrusion area are connected to each other. In paragraph 2,
The first acoustic element and the second acoustic element are positioned in one of the protruding regions. In claim 1,
The space between the acoustic element and the rear chassis serves as a ringtone. In paragraph 6,
The rear chassis partitions the space. In clause 7,
The first acoustic element and the second acoustic element are located in the space. In paragraph 2,
A display device in which at least one open portion is positioned adjacent to the protruding area. In claim 9,
The at least one open portion is disposed parallel to an edge of the protruding area. In claim 9,
The display device of the at least one open portion is located on the rear chassis. In claim 1,
The display panel is an organic light emitting display panel. In claim 1,
The acoustic element includes a pair of electrodes and a vibrating material layer interposed therebetween. In clause 7,
Further comprising an adhesive for attaching the acoustic element and the rear chassis,
The adhesive is a display device including a non-conductive epoxy. In claim 1,
The display panel includes a substrate, a printed circuit board, and a flexible circuit board,
The substrate of the display panel is connected to the printed circuit board through the flexible circuit board,
An amplifier is formed on the printed circuit board. In claim 1,
The vibrating material layer of the acoustic element also generates vibration at a frequency other than the audible frequency,
A display device implementing a haptic function by detecting a change in frequency other than the audible frequency and sensing a user's touch. In claim 1,
A display device in which the acoustic element senses pressure by using a voltage generated by external pressure. In claim 1,
The display device further includes a microphone,
A display device configured to sense a user's motion by detecting a vibration of a frequency other than the audible frequency emitted from the acoustic element according to a Doppler effect according to a user's motion and then sensing it by the microphone. In claim 1,
Further comprising a battery for supplying power to the display device,
A display device charging the battery by transferring a voltage generated while the acoustic element vibrates to the battery.

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