KR102332256B1 - Display device - Google Patents

Abstract

The present invention provides a display panel for displaying an image; an acoustic element providing sound; and a rear chassis accommodating the display panel to protect a rear surface of the display panel, wherein the acoustic device is attached to the rear chassis, and at least one open portion is positioned around the acoustic device. .

Description

display device {DISPLAY DEVICE}

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

The display device has evolved from the conventional cathode ray tube (CRT) method using a cathode ray tube, and is a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting display (OLED), an electrowetting display (EWD), and an electrophoretic display (EPD). Various flat display devices such as display), embedded micro cavity display (EMD), and nano crystal display (NCD) are being developed.

Among these flat panel displays, a liquid crystal display (LCD), which has recently been spotlighted, has advantages such as miniaturization, light weight, and low power consumption, and thus can overcome the disadvantages of the existing cathode ray tube (CRT). It has been gradually attracting attention as an alternative means of having a display device, and is currently being installed and used in almost all information processing devices requiring a display device. In a liquid crystal display device, 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 mutually connected to each other. It is a device that forms an electric field by applying different potentials, changes the arrangement of liquid crystal molecules, and displays an image by controlling light transmittance.

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

Meanwhile, an organic light emitting diode display among flat panel displays has an advantage in that it does not use 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 have disadvantages in that a separate speaker must be installed to provide sound.

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

An object of the present invention is to provide a display device capable of generating a sound without installing a separate speaker or enabling a touch or motion detection without adding a separate touch panel/touch sensor.

In order to solve the above problems, a display device according to an embodiment of the present invention includes a display panel for displaying an image; an acoustic element providing sound; and a rear chassis accommodating the display panel to protect a rear surface of the display panel, wherein the acoustic device is attached to the rear chassis, and at least one opening is positioned around the acoustic device.

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

A space between the acoustic element and the rear chassis may serve as a resonator.

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 protrusion area.

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

The protrusion region and the acoustic device may correspond one-to-one.

The acoustic element may be located in the protruding area.

Another acoustic element for providing sound, further comprising another acoustic element attached to the rear chassis, wherein the rear chassis has another protruding area, and the another acoustic element may be located within the another protruding area.

The protrusion area and the other protrusion area may be connected to each other.

Another acoustic device for providing a sound, and further comprising another acoustic device attached to the rear chassis, wherein the acoustic device and the other acoustic device 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 disposed therebetween.

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

The display panel may include a board, a printed circuit board, and a flexible circuit board, the board 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 device may also generate vibration of a frequency other than an audible frequency, and may implement a haptic function by sensing a user's touch by sensing a change in a frequency other than the audible frequency.

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

The display device may further include a microphone, and after vibration of a frequency other than the audible frequency emitted from the acoustic device is modulated according to the Doppler effect according to the user's motion, the microphone may sense the user's motion.

The display device may further include a battery that supplies power to the display device, and may charge the battery by transferring a voltage generated when the acoustic device vibrates to the battery.

The number of the acoustic elements may be two or more.

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

As described above, a piezo material (eg, a material such as PVDF or PZT) that provides sound by receiving an electric field is formed to provide sound in the display device. In addition, when a user touches a touch using vibration instead of an audible frequency, it is possible to receive feedback and sense the touch, thereby eliminating the need to form a separate touch screen. In addition, the movement of the hand in the vicinity of the display device may be sensed by the Doppler effect, so that a separate motion sensor may not be included.

1 is a cross-sectional view of a display device according to an exemplary embodiment.
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.
5 to 10 are graphs illustrating 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 embodiments of a display device according to an exemplary embodiment of the present invention.
19 to 22 are diagrams illustrating 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.

With reference to the accompanying drawings, the embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In order to clearly express various layers and regions in the drawings, the thicknesses are enlarged. Throughout the specification, like reference numerals are assigned to similar parts. When a part, such as a layer, film, region, plate, etc., is "on" another part, it includes not only the case where it is "directly on" another part, but also the case where there is another part in between. Conversely, when we say that a part is "just above" another part, we mean that there is no other part in the middle.

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

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

In the display device according to the exemplary embodiment of the present invention, the display panel 70 and the rear chassis 28 housing the display panel 70 and protecting the rear surface thereof, the rear chassis 28 having the protruding area 28-1, and the protruding area 28- 1) comprising an acoustic element 27 located within.

The display panel 70 in the embodiment of FIG. 1 may be a display panel that emits light by itself or a light-receiving type display panel that displays an image by receiving light from a light source. 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 including a plurality of thin film transistors (TFTs), the TFT substrate is a transparent insulating substrate on which thin film transistors in a matrix are 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 indium tin oxide (ITO) 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 for driving.

The data line and the gate line of the display panel 70 are connected to the flexible circuit board, and when an electrical signal is input from the flexible circuit board, the electrical signal is transmitted to the source terminal and the gate terminal of the TFT, and the gate is passed through the double gate line. The TFT is turned on or off according to the scan 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 driving signals to data lines and gate lines 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 outputs the image signal and the scan signal to the display panel 70 . applied to the gate line and data line of In addition, in the flexible circuit board according to the embodiment of the present invention, an amplifier (refer to FIG. 23 ) for amplifying and transmitting an acoustic signal may be formed. The amplifier receives the acoustic signal received from the outside, amplifies it, and transmits the acoustic signal to the acoustic device 27 through the acoustic 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 the display panel 70 from being separated 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 . Such a 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 according to an exemplary embodiment.

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

The protruding region 28 - 1 is a region in which the acoustic device 27 is located and may serve as a resonator for amplifying a sound provided from the acoustic device 27 .

An acoustic element 27 is attached to the inner surface of the protruding region 28-1 of the rear chassis 28 by means of an adhesive 51 . The adhesive 51 may use an adhesive including a non-conductive epoxy. At this time, heat may be applied or natural drying may be performed to dry the adhesive 51 . When heat is applied to the acoustic element 27 , the properties of the vibration material layer 27 - 1 deteriorate. This was confirmed by the reliability test results. In the case of attaching the acoustic element 27 to this, even if it takes time, natural drying may be performed. However, when the sound quality provided by the acoustic device 27 is not important (eg, a receiver that provides the other party's voice from the phone, etc.), it may be dried by applying heat.

The acoustic device 27 includes a pair of electrodes 27-2 and a vibrating material layer 27-1 disposed therebetween. The vibrating material layer 27-1 includes a piezo material that vibrates by an electric field provided by a pair of electrodes 27-2 positioned vertically, and an example of the piezo material is PVDF (Poly Vinylidene Fluoride). or PZT (zircon titanium shovel lead ceramic).

PVDF includes PVDF-TrFE (polyvinylidene fluoride trifluoroethylene), and has material properties that are easy to manufacture in the form of a flexible film. On the other hand, PZT is difficult to weave in the form of a film compared to PVDF, so it is difficult to have flexible characteristics. However, in some embodiments, 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 respectively positioned on both sides of the vibrating material layer 27 - 1 , and provide an electric field to the vibrating material layer 27 - 1 . The electrode 27 - 2 may use various conductive materials such as a transparent conductor such as ITO or IZO, an opaque metal, a conducting polymer, and carbon nanotube (CNT).

The acoustic element 27 is attached to the inner surface of the protruding region 28-1 of the rear chassis 28 and vibrates. The protrusion region 28 - 1 also vibrates due to the vibration of the acoustic element 27 , and as a result, the entire rear chassis 28 vibrates while the vibration is transmitted to the display panel 70 . Since this is determined according to the material of the rear chassis 28 and the magnitude of vibration provided by the acoustic device 27 , a problem may not occur if the actual vibration of the acoustic device 27 is relatively small. In order to eliminate the possibility that a problem may occur due to vibration provided by the acoustic element 27, an open part ( 28-2) is formed. The open part 28-2 not only serves to buffer the vibration of the acoustic element 27 from being transmitted to the rear chassis 28 as it is, but also serves as the protruding area 28-1 to faithfully serve as a resonator when vibrating. It also serves to improve the movable range of the protruding region 28-1 so that the In addition, the 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 portion of the boundary of the protruding area 28 - 1 , and the length and width thereof have various structures according to embodiments. It is also arranged at a regular interval from the adjacent open portion 28-2.

Referring to FIG. 2 , the open part 28 - 2 is located within the protruding area 28 - 1 , and may be located outside the protruding area 28 - 1 according to an exemplary embodiment.

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

Meanwhile, in some embodiments, a window formed 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 a display-side outer surface of a portable electronic device such as a mobile phone or other electronic device.

1 illustrates an embodiment in which one acoustic device 27 is included, the number of acoustic devices 27 may include 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.

3 and 4 are different from the embodiment of FIG. 2 in that the presence and location of the open part 28-2 is different.

First, the embodiment of FIG. 3 will be described.

The display device 100 according to the embodiment of FIG. 3 has the protruding area 28-1 and the wiring connection part 28-3 on the rear chassis 28, but does not include the open part 28-2. Example.

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

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

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

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

As shown in FIG. 5 , in the display device 100 of the embodiment for testing acoustic characteristics, an embodiment including two acoustic elements (speakers) was used. That is, at positions 1 and 2 of FIG. 5 , 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 portion indicated by the triangle in FIG. 5 is fixed, and in FIG. 5 shows the embodiment as in FIG. 3 without the opening 28-2 near the protruding area 28-1, but , in the experiment, the embodiment (e1_base) as in FIG. 3 without the open part 28-2, and the embodiment (e1_slit) as in FIG. 2 in which the open part 28-2 is inside the protruding area 28-1 (e1_slit) in) and the open portion 28-2 were measured using the example (e1_slit out) as shown in FIG. 4 in which the protruding area 28-1 is outside.

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

In the embodiment of Fig. 6, the acoustic characteristic at the position 1 is shown as a graph, in Fig. 7 the acoustic characteristic at the position 2 is shown, and in Fig. 8, the acoustic characteristic at the position 3 is shown, in 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 with respect to frequency, and the smaller the stiffness, the more advantageous the sound amplification is.

6 to 10, it can be seen that the embodiment with the open part 28-2 has a better sound amplification effect than the embodiment without the open part 28-2, and the open part 28- The embodiment in which 2) is located outside the protruding region 28-1 had a good sound amplification effect, and in the intermediate frequency region therebetween, the open portion 28-2 is located inside the protruding region 28-1. The example in which 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), and the embodiment as in FIG. 2 in which the open part 28-2 is inside the protruding area 28-1 After vibrating the embodiment (slit out) as in FIG. 4 in which the (slit in) and the open part 28-2 are on the outside of the protruding area 28-1, the results of photographing the vibration characteristics at each frequency are shown. are doing

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

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

Therefore, it is possible not only to adjust the position of the open part 28-2 according to the frequency characteristics of the mainly used sound, but also to form the open part 28-2 both inside and outside the protruding area 28-1. have.

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

First, in FIG. 12 , various modifications of the protruding area 28 - 1 in the rear chassis 28 will be described.

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

In addition to the circular shape of the rear surface of the protruding area 28-1, various shapes such as an oval or a quadrangular structure with rounded corners are shown. Contrary to the drawings, it may have a quadrilateral structure with angled corners, a polygonal structure with rounded corners, and a polygonal structure with angled corners.

One acoustic device 27 may be formed in the protruding region 28-1, but two or more acoustic devices 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 region 28 - 1 .

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

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

The shape of the protruding area 28-1 shown in FIG. 12 is only an example of various embodiments, and the embodiment of the present invention is not limited to the protruding area 28-1 of FIG.

13 shows a more specific structure of the rear chassis 28 including an open part 28-2 and a wiring connection part 28-3 based on the circular protrusion area 28-1. Various embodiments are shown in FIG. 13 according to the position of the open portion 28-2 and the number of the protruding regions 28-1. 13 shows an embodiment in which two acoustic elements 27 are provided.

First, an embodiment having one protruding area 28 - 1 will be described. Two acoustic elements 27 are included in one protrusion region 28-1, and one wiring connection part 28-3 is formed to correspond to one protrusion region 28-1. At this time, in one embodiment, the position of the open part 28 - 2 is outside the protruding area 28 - 1 , and in another exemplary embodiment, the position of the open part 28 - 2 is inside the protruding area 28 - 1 . Depending on the embodiment, the open part 28-2 may not be included.

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

In FIG. 13 , two acoustic devices 27 are shown. If the two acoustic devices 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 having various shapes of FIG. 12 , and thus, more embodiments may be formed by combining 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.

14 to 18 show various embodiments, focusing on an embodiment in which the cushion tape 70-1 is used instead of the rear chassis 28. As shown in FIG. 14 to 18 , the rear chassis 28 may be included in the 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, an additional rear chassis 28 may be located on the rear surface of the cushion tape 70-1. Also, since there may be an embodiment in which the window 30 is formed on the front surface of the display panel 70 in FIGS. 14 to 18 , this is illustrated by a dotted line. The window 30 is not necessarily included, and is formed of tempered glass or plastic to prevent the front surface of the display panel 70 from being damaged from the outside. The window 30 may constitute a display-side outer surface of a portable electronic device such as a mobile phone or other electronic device.

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

The display device 100 according to an embodiment of the present invention includes a display panel 70 , an acoustic device 27 positioned on the rear surface of the display panel 70 , and a rear surface of the display panel 70 and an acoustic device 27 covering the rear surface of the display panel 70 . and a cushion tape 70-1. In some embodiments, 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 rear surface of the display panel 70 and the acoustic device 27 . The cushion tape 70-1 may be formed of a material having elasticity, and may have a black color that blocks light.

As shown in FIG. 14 , the cushion tape 70-1 covering the acoustic device 27 may have a certain space formed around the acoustic device 27 to serve as a resonator for resonating the sound of the acoustic device 27 . have.

In some embodiments, reference numeral 70 in FIG. 14 may indicate 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 for driving.

The display panel 70 or the display panel assembly in the embodiment of FIG. 14 may be a display panel that emits light by itself or a light-receiving type display panel that displays an image by receiving light from a light source. 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 the display panel 70 from being separated in the front direction, and a rear chassis called a bottom chassis or a back chassis may be further included on the rear surface.

14 illustrates an embodiment in which one acoustic device 27 is included, the number of acoustic devices 27 may include two or more.

Meanwhile, in the embodiment of FIG. 14 , the rear surface of the display panel 70 and the acoustic device 27 are 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, damage to the glass substrate may occur due to direct contact between the acoustic device 27 and the glass substrate.

Accordingly, 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 thereunder. An embodiment is also possible.

14 and 15 , the cushion tape 70 - 1 covers the acoustic device 27 , and a sound is resonated and amplified by the space generated around the acoustic device 27 .

However, when the height of the actual acoustic device 27 is not high, the space with the cushion tape 70 - 1 is narrow, which may not be sufficient to serve as a sounder.

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

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 positioned 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 concave resonant space 70 - 11 .

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

In the embodiment of FIG. 16 , the acoustic device 27 may be attached to the rear surface of the display panel 70 . In FIG. 17 , the acoustic device 27 is disposed in the resonant space 70-11 of the cushion tape 70-1. An embodiment fixed within is shown.

As shown in FIG. 17 , a fixing 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 fixing protrusion 70-12. It is fixed and is fixed in the ringing 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 embodiment of FIG. 17 , although the acoustic device 27 is in contact with the rear surface of the display panel 70 , it may not be attached with an adhesive, and may be connected to the rear surface of the display panel 70 by the fixing protrusions 70 - 12 . It may be attached and fixed. The fixing protrusion 70-12 serves to prevent the position of the acoustic element 27 from being changed even if it is not attached by an adhesive.

On the other hand, an embodiment in which there is no component covering the acoustic element 27 is possible depending on the embodiment. That is, like the display device illustrated in FIG. 18 , the acoustic device 27 is positioned on the rear surface of the display panel 70 , and no components may be formed on the rear surface.

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

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

First, the acoustic element 27 of FIG. 19 will be looked at.

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 by a pair of electrodes 27-2 positioned vertically, and an example of the piezo material is PVDF (Poly Vinylidene Fluoride). or PZT (zircon titanium shovel lead ceramic).

Based on the vibrating material layer 27-1, one electrode 27-2 is located on the upper part, and the other electrode 27-2 is located on the lower part. In the embodiment of FIG. 19, the electrode positioned on the lower part An embodiment is shown in which a portion of the vibration material layer 27-1 climbs up the side surface of the vibration material layer 27-1 and is positioned 27-21 on the upper part of the vibration 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, wiring 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 placed on the upper part. When positioned, there is an advantage that it can be directly connected to the two electrodes from the top. As a result, the lower part of the acoustic element 27 may receive a signal through the upper part even if it is attached with an adhesive or the like.

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

As described above, in the acoustic device 27, a pair of electrodes 27-2 are basically positioned at the upper and lower portions, and according to the embodiment, one electrode may be used by changing to another structure.

Referring to FIG. 21 , the acoustic device 27 includes one upper electrode 27-2 and a vibrating material layer 27-1 below it. A rear chassis 28 is positioned under the vibrating material layer 27-1. The rear chassis 28 is formed of a conductive material, and in this case, 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, one electrode is omitted, and the corresponding component (rear chassis 28 in FIG. 21) is used to serve as an electrode It also shows that it can be done. At this time, it is preferable not to receive an electrical signal other than the signal from the amplifier to the component replacing the electrode, such as the rear chassis 28 .

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

Hereinafter, the multi-layered acoustic device 27 will be described with reference to FIG. 22 .

The acoustic device 27 according to the embodiment of FIG. 22 includes three vibrating 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 positioned on the outermost side of the three-layered vibrating material layer 27-1 and between them. . A total of four electrodes are electrically connected to each other two by two, and are alternately arranged. The electrode 27-2 located at the bottom and the electrode 27-2 located at the top receive different signals, and the electrode 27-2 located in the middle is the vibration material layer 27-1. It is connected to the uppermost electrode 27-2 or the lowermost electrode 27-2 along the side surface. The lowermost electrode 27-2 is configured such that the electrode pads 27-21 are positioned next to the uppermost electrode 27-2 so that wiring can be easily connected. As a result, each of the vibrating material layers 27-1 vibrates with the electric field generated because the electrodes 27-2 contacting up and down apply different signals, thereby generating sound. In the embodiment of FIG. 22 , three vibration material layers 27 - 1 exist to generate a higher sound pressure than the acoustic device 27 in which only one vibration material layer 27 - 1 exists.

Hereinafter, the amplifier 80 providing a signal to the acoustic device 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 located on the printed circuit board 78 . The amplifier 80 may be located inside a signal controller (not shown) that controls image display of 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 a signal is transmitted to the acoustic device 27 through the acoustic signal wiring 80 - 1 formed on the display panel 70 . is authorized

The amplifier 80 receives the acoustic signal received from the outside, amplifies it, and transmits the acoustic signal to the acoustic device 27 through the acoustic signal wiring 80 - 1 .

Such an amplifier 80 may be implemented in various integrated circuit configurations, one 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 supply 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). The four input signals are amplified and converted according to the signal 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 acoustic signal to the amplifier 80 .

Hereinafter, an embodiment in which the acoustic element 27 is used in a manner other than providing sound to the user 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, 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 in FIG. 25 .

Vibration is generated in the display device 100 as a whole by the acoustic element 27 , and among them, low vibrations other than the audible frequency are also generated as shown in FIG. 25 . Since this frequency is inaudible to the user, the sound quality is not affected even if it is used for other purposes. A touch may be sensed by sensing a vibration that changes when the user touches the display device 100 . Sensing of such a touch may be a level 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 by using vibrations other than the audible frequency provided by the acoustic device 27 and confirming whether the user touches or not. To this end, a sensor capable of detecting vibration of a low frequency rather than an audible frequency may be additionally provided, and the realization of haptics using the sensor is a signal controller for displaying an image in the display device 100 or a mobile terminal in a portable terminal. It may be performed in a 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 device 27 generates sound while vibrating by an electric field. 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 can be confirmed that the displacement is generated while being pressed by the pressure, thereby serving as a pressure sensing function.

Pressure sensing using the acoustic device 27 may additionally include a sensor 85 capable of detecting a voltage generated from the acoustic device 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 time-divided to perform the role of a pressure sensor with one amplifier 80. You may.

27 illustrates an embodiment in which a motion of a user's hand is sensed using the Doppler effect.

When a high-frequency or low-frequency sound wave is generated from the acoustic element 27 located inside the display device 100 , rather than an audible frequency, when the user moves his or her hand in front of the display device 100 , the generated sound wave is changed and portable. A sound wave is input to the microphone 130 of the terminal. As shown in FIG. 28 , the sound wave is transmitted to the microphone 130 as the sound pressure becomes stronger or weaker due to the Doplo effect caused by the movement of the user's hand, and the user's hand by detecting the fluctuation of the sound wave provided to the microphone 130 Motion sensing is possible to detect the movement of

In order to perform motion sensing using the acoustic device 27 , the microphone 130 is absolutely necessary, and when the display device 100 including the acoustic device 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, the motion sensing shown in FIG. 27 does not require image processing by a camera and has the advantage of being simple because only the sound pressure input to the microphone 130 is considered.

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

26 , when the vibrating material layer 27-1 included in the acoustic device 27 vibrates without an electric field, a voltage is generated from the vibrating material layer 27-1. The voltage generated in this way may be stored in the capacitor or the battery 87 to increase the use time of the battery. Since a mobile terminal generally used is carried with the user when moving, it is exposed to a certain level of vibration. Therefore, when the acoustic device 27 is included, the acoustic device 27 itself vibrates to generate a voltage, which is transmitted 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 the user shaking the mobile terminal including the sound element 27 or touching it tens to hundreds of times using a finger. can

As described above, another effect of the acoustic device 27 shown in FIGS. 25 to 29 may be performed together through time division driving in the middle of the acoustic device 27 providing sound using one acoustic device 27 . . In addition, a separate acoustic device 27 may be additionally formed, and the acoustic device 27 may be connected to a separate sensor or battery to perform only a sensing operation or a battery charging operation without being connected to the amplifier.

In the present invention, it is described that the acoustic device 27 is located in the display device 100 , but in order to have the characteristics of FIGS. 25 to 29 , the acoustic device 27 is the display device 100 is used in the portable terminal. It suffices to be located somewhere, and does not necessarily have to be located in the display device 100 .

Although 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 as defined in the following claims are also provided. is within the scope of the

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: Resonant space
70-12: fixed protrusion 70-2: protective film
78: printed circuit board 79: flexible circuit board
80: amplifier 80-1: acoustic signal wiring
85: sensor 87: battery
130: microphone

Claims (19)

a display panel for displaying an image;
a first acoustic element and a second acoustic element providing sound; and
and a rear chassis housing the display panel to protect a rear surface of the display panel;
The acoustic element is attached to the rear chassis,
The display device includes two or more of the acoustic elements. In claim 1,
The rear chassis has a protruding area. In claim 2,
The protruding area has a first protruding area and a second protruding area,
The first acoustic element is located in the first protruding area,
The second acoustic element is positioned in the second protrusion area. In claim 3,
The first protrusion area and the second protrusion area are connected to each other. In claim 2,
The first acoustic device and the second acoustic device are positioned in one of the protruding regions. In claim 1,
A space between the acoustic element and the rear chassis serves as a resonator. delete In claim 6,
The first acoustic device and the second acoustic device are positioned in the space. In claim 2,
A display device in which at least one open part is positioned adjacent to the protrusion area. In claim 9,
The at least one open portion is disposed parallel to an edge of the protrusion area. In claim 9,
The at least one open part is positioned on the rear chassis. In claim 1,
The display panel is an organic light emitting display panel. In claim 1,
The acoustic device includes a pair of electrodes and a vibrating material layer disposed therebetween. In claim 1,
Further comprising an adhesive for attaching the acoustic element and the rear chassis,
The adhesive includes 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 a display device formed on the printed circuit board. In claim 1,
The vibration material layer of the acoustic element also generates vibrations of frequencies other than audible frequencies,
A display device implementing a haptic function by sensing a user's touch by detecting a change in a frequency other than the audible frequency. In claim 1,
A display device in which the acoustic element performs pressure sensing using a voltage generated by external pressure. In claim 1,
The display device further includes a microphone,
A display device that detects a user's motion by detecting vibrations of frequencies other than the audible frequency emitted from the acoustic element by the microphone after being modulated according to a Doppler effect according to a user's motion. In claim 1,
Further comprising a battery for supplying power to the display device,
A display device for charging the battery by transferring a voltage generated when the acoustic element vibrates to the battery.

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