CN113286224A - Display device and sound production method thereof - Google Patents

Abstract

The embodiment of the invention discloses a display device and a sound production method thereof. In one embodiment of the invention, a display device includes: the display screen further includes a controller and at least one phased speaker array, the phased speaker array including a plurality of speakers, the controller configured to control the phased speaker array to focus deflection or beam deflection to emit sound waves toward a top surface of the listening environment for reflection to a listening area within the listening environment. The embodiment has the advantages that the phased loudspeaker array is arranged in the display device, and the phased loudspeaker array is controlled to focus and deflect or deflect the sound beam, so that the sound wave signal containing height information and reflected from the top surface of the listening environment can be received in the listening area, the spatial height perception of a listener is enhanced, and the phased loudspeaker array has wide application prospect.

Description

Display device and sound production method thereof

Technical Field

The invention relates to the technical field of audio signal processing. And more particularly, to a display device and a sound emission method thereof.

Background

The space left for the sound production device by the ultra-thin and narrow frame of the display device and even the full screen design is smaller and smaller. At present, display devices have appeared which utilize the entire screen as a diaphragm to produce sound in a display. In the design, the display device can directly sound to realize sound and picture synchronization, can effectively utilize space and save resources, and can improve sound production power and realize different sound field effects when being combined with a large-size screen. The existing screen sounding unit can be attached with an exciter, such as a piezoelectric film, on the back of a screen, and the exciter drives the screen to vibrate, so that the whole screen is driven to vibrate, and the screen is pushed to sound.

A good sound effect can provide the audience with an immersive and highly accurate audio position, which involves arranging a plurality of loudspeaker arrays in a room. In a home entertainment environment, viewers are also seeking to reproduce audio information originating from above the viewer in three-dimensional space while watching television. To achieve this, it is conventional to mount additional height speakers on the ceiling, but such height speakers can be difficult to mount for many consumers. If a speaker unit is simply added to the television to play the sound source of the height information, as shown in fig. 1, most of the sound wave information is directly radiated to the sofa, so that the height information of the sound source is lost, the direction sense of the sound wave is reduced, and the experience of radiating the sound wave from a high place cannot be brought to a client.

Accordingly, there is a need for a speaker design that is easy or non-easy to install and that emits sound equivalent to a ceiling-derived sound source that effectively plays audio of an audio object representing height information.

Disclosure of Invention

An object of the present application is to provide a display device and a sound generating method thereof, so as to solve at least one of the problems in the prior art.

In order to achieve the purpose, the following technical scheme is adopted in the application:

a first aspect of the application provides a display device comprising a display screen, further comprising a controller and at least one phased speaker array, the phased speaker array comprising a plurality of speakers, the controller being configured to control the phased speaker array to focus deflection or beam deflection to emit sound waves towards a top surface of a listening environment for reflection to a listening area within the listening environment.

In some alternative embodiments, the speaker is a piezoelectric speaker.

In some alternative embodiments, the display device is a sound-on-screen display device.

In some alternative embodiments, the display device includes two phased speaker arrays disposed in upper left and right regions.

In some alternative embodiments, the phased speaker array is a one-dimensional phased speaker array or a two-dimensional phased speaker array.

In some alternative embodiments, the plurality of loudspeakers in the one-dimensional phased loudspeaker array are arranged in a vertical arrangement.

In some alternative embodiments, the plurality of speakers in the two-dimensional phased speaker array are arranged in a rectangular arrangement or a circular arrangement.

In some alternative embodiments, the controller is configured to control the phased speaker array focus deflection or beam deflection by controlling speaker voicing delays in the phased speaker array.

In some optional embodiments, the controller is configured to calculate a deflection angle from sound waves reflected by a top surface of the listening environment and sound waves reflected by objects in the listening area received by the piezoelectric speaker, and to control the phased speaker array to focus or deflect the sound beam according to the deflection angle.

The second aspect of the present invention provides a sound generating method for a display device, including:

controlling at least one phased speaker array disposed at the display device to focus deflection or beam deflection to emit sound waves toward a top surface of the listening environment for reflection to a listening area within the listening environment.

The invention has the following beneficial effects:

aiming at the existing problems, the invention sets a display device and a sound production method thereof, and a phased loudspeaker array and a controller are arranged in the display device, and the controller controls the phased loudspeaker array to focus and deflect or deflect sound beams, so that the phased loudspeaker array emits sound waves towards the top of a listening environment to be reflected to the listening area in the listening environment, a listener can experience head top radiated sound without additionally installing a ceiling loudspeaker, the spatial height perception of the listener is enhanced, the requirement of the listener on surround sound of an upper sound source is met, and the display device has wide application prospect.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Fig. 1 shows a schematic side view of a prior art display device in which the emitted sound waves are directly emitted without deflection.

Fig. 2 shows a schematic side view of a display device emitting sound waves to a ceiling according to an embodiment of the present invention.

Fig. 3 shows a schematic front view of a display device emitting sound waves to a ceiling according to an embodiment of the present invention.

Fig. 4 shows a schematic configuration diagram of a speaker in a display apparatus according to an embodiment of the present invention.

Fig. 5a shows a schematic view of the principle of focus deflection of a two-dimensional phased loudspeaker array in a display device according to an embodiment of the invention.

Fig. 5b shows a schematic diagram of the principle of deflection of sound beams of a one-dimensional phased speaker array in a display device according to an embodiment of the present invention.

Fig. 6 shows a schematic diagram of physical parameters of a listening environment of a display device of an embodiment of the invention.

Fig. 7 shows a schematic perspective top view of a display device according to an embodiment of the invention.

Fig. 8 shows a schematic perspective top view of a display device according to another embodiment of the invention.

Fig. 9 shows a schematic perspective top view of a display device according to another embodiment of the invention.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. Like parts in the drawings are denoted by the same or similar reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.

It should be noted that, when the description "has", "includes", "including", etc. in the present invention are all open-ended, that is, when the description module "has", "includes" or "includes" the first element, the second element and/or the third element, it means that the module includes other elements in addition to the first element, the second element and/or the third element.

To solve one of the above problems, an embodiment of the present invention provides a display device including a display screen, further including a controller and at least one phased speaker array, the phased speaker array including a plurality of speakers, the controller configured to control the phased speaker array focus deflection or beam deflection to emit sound waves toward a top surface of a listening environment for reflection to a listening area within the listening environment.

In this embodiment, through set up phased loudspeaker array and controller in display device, and this phased loudspeaker array focus of controller control is deflected or the sound beam deflects for thereby phased loudspeaker array reflects the listening area in listening environment towards listening environment's top outgoing sound wave, makes the listener needn't additionally install ceiling speaker can experience the top of the head radiated sound, has strengthened the high perception in space of listener, satisfies the listener and to the demand of top sound source surround sound, has extensive application prospect.

In one particular example, and as shown with reference to fig. 2 and 3, in a listening environment, such as a living room, a television set 200 is mounted or erected as a display device, the television set including a display screen 201, a controller (not shown), two phased speaker arrays 202-1 and 202-2. A sofa is placed in front of the display screen of the television 200, and the area where the sofa is located is the listening area of the listening environment.

Of course, the display device may be a computer, an electronic whiteboard, or other display device including a display screen, the listening environment may be an office or a conference room, and the listening area may be a seat in the office or the conference room, accordingly. For convenience of description, the above-described television in the living room is described instead of the display device, and those skilled in the art should not be construed as limiting the present invention.

Alternatively, the speakers in phased speaker arrays 202-1 and 202-2 may be piezoelectric speakers. As shown in fig. 4, the piezoelectric speaker is specifically composed of a piezoelectric multilayer stacked structure, which includes upper and lower electrodes and a middle piezoelectric layer, the upper and lower electrodes respectively cover the upper and lower sides of the piezoelectric material, and after the electrodes are powered on, an electric field is applied to the piezoelectric material, so that the piezoelectric material generates deformation and generates sound under the action of the electric field. The electrode material can contain silver as its main component, and the piezoelectric layer material can be film type piezoelectric ceramic PZT or PVDF film. The piezoelectric speakers have length and width dimensions of 0.5cm or more and 5cm or less, and when two-dimensional arrays of piezoelectric speakers are arranged, the transverse or longitudinal dimension of the arrays may be 5cm or more and 50cm or less. The television 200 in the embodiment of the present invention is an on-screen sound display device.

The phased speaker arrays 202-1 and 202-2 may be disposed on either the back side of the display screen 201 as shown in fig. 2 or the front side of the display screen opposite the back side. When setting up at the back of display screen 201, compare the condition that phased loudspeaker array set up at the front, do not occupy the display area of display screen, therefore do not influence full-screen picture and show, the display screen can realize being narrow frame display screen.

In addition, although the television set 200 is shown in this example as including two phased speaker arrays 202-1 and 202-2, the present application is not intended to be so limited, and the television set 200 may include one or more phased speaker arrays, and the specific location of each phased speaker array on the television set 200 is not limited. For example, as shown in FIG. 3, when two phased speaker arrays 202-1 and 202-2 are provided, the two phased speaker arrays 202-1 and 202-2 are provided in the upper areas on the left and right sides of the television set 200. When a phased speaker array is provided, the phased speaker array may be located in an upper central region of the television or other location as deemed appropriate by the designer.

Each of the phased speaker arrays 202-1 and 202-2 includes a plurality of speakers, which may form a one-dimensional phased speaker array or a two-dimensional phased speaker array.

In particular, with the arrangement of the present example, two phased speaker arrays 202-1 and 202-2 are provided in the television set 200, which can generate focus deflection or acoustic beam deflection under the control of a controller, and through the focus deflection or acoustic beam deflection action, the television set 200 is caused to emit sound waves toward the ceiling of the living room by two phased speaker arrays 202-1 and 202-2, the sound waves are reflected at the ceiling and reflected to the listening area where the sofa is located, so that a listener sitting at any position on the sofa can receive the sound wave signal radiated from the ceiling direction above the head, so that it is not necessary to install an additional speaker device at the ceiling, namely, the listener on the sofa as the listening area can perceive the sound effect with spatial height, realizing the surround sound effect with height information.

Specifically, the controller is configured to control the phased speaker array focus deflection or acoustic beam deflection by controlling speaker voicing delays in the phased speaker array.

Because the sound waves can be superposed, for a plurality of sound wave signals, the strength of the sound wave signals with the same phase is enhanced, and the strength of the sound wave signals with opposite phases is weakened. In the embodiment of the invention, the phase is controlled by utilizing the corresponding relation between the delay and the phase of the transmitted sound wave and controlling the delay relation of the sound wave signals transmitted by different loudspeakers in the phased array loudspeaker, so that the sound wave signals of all paths are mutually superposed, focused and deflected or the sound beam is deflected.

To further understand the focus deflection and acoustic beam deflection that occurs with phased speaker arrays. The control principle of the focus deflection and the acoustic beam deflection is described below in connection with fig. 5a-5 b.

Fig. 5a shows a schematic diagram of the principle of focus deflection of a two-dimensional phased loudspeaker array.

First, for focus deflection, each loudspeaker in each phased loudspeaker array deflects an outgoing sound wave signal by an angle θ i away from a central axis in a vertical direction of the loudspeaker array, where i represents the ith loudspeaker in the two-dimensional phased loudspeaker array. Referring to fig. 5a, the wavefront of the sound wave generated by each speaker is concentrated at a point on the ceiling, thereby achieving focusing and deflection of the sound beam. Because the wave front of the sound wave is concentrated on a point on the ceiling, and the sound wave is focused and deflected, the radiation is reflected on the ceiling in the manner shown in fig. 3 to cover the listening area where the sofa is located. The speaker is deviated by an angle thetai with respect to the center axis of the vertical direction of the speaker array. In an implementation manner in which the phase of the outgoing sound wave is controlled correspondingly with the delay of the sound wave signal to generate the focus deflection, in the delay expression for calculating the focus deflection, the deviation angle of the outgoing direction of the speaker at the center of the array from the central axis is taken as the deflection angle θ of the two-dimensional phased speaker array.

As shown in the figure, for the two-dimensional phased speaker array, if the plane on which the two-dimensional phased speaker array is located is taken as the plane on which the y axis and the x axis are located in the figure, and an xyz coordinate system is established, and the center of the array is taken as the origin, the central axis is taken as the z axis, and θ is the angle in which the direction of the speaker outgoing sound wave at the center of the array deviates from the z axis. As will be understood by those skilled in the art, for a one-dimensional phased speaker array, the angle θ is the angle at which the direction of the outgoing sound wave deviates from the direction in which the array of phased speaker arrays is arranged.

Referring to fig. 6, in the embodiment of the present invention, the exit deflection angle θ is an angle determined according to a distance D from the television 200 to an object (sofa) in the listening area and a distance H from the television 200 to the ceiling:

θ＝atan((H/2)/D) (1)。

if the sound wave is focused and deflected, the required emergent delay is determined according to the deflection angle, and the specific emergent delay tm in each column meets the following conditions:

where F is the depth of focus, c is the speed of sound, Xm is the length of the axis from the mth loudspeaker to the focal point in a line of loudspeakers, d is the loudspeaker spacing, and θ is the deflection angle.

Therefore, as can be seen from the above control method, the radiation directions of the focused acoustic waves in each column are arranged in parallel with each other, and the delay times of the speaker units in the same row in different columns are the same. Accordingly, it can be understood that the arrangement of the plurality of speakers in the one-dimensional phased speaker array is vertical, i.e., referring to the direction perpendicular to the lower frame of the display screen of the television 200, so as to ensure that the sound wave emitted from each speaker has a delay time and thus the focus deflection is ensured.

Fig. 5b shows a schematic diagram of the principle of beam deflection for a one-dimensional phased loudspeaker array. For sound beam deflection, the sound beams can be deflected and emitted in parallel by controlling each loudspeaker in the array to deflect at the same deflection angle theta without focusing on one point on a ceiling, and the sound beams can also be radiated to cover the listening area where the sofa is located after being reflected by the ceiling, and in addition, although fig. 5b only shows the principle schematic diagram of sound beam deflection of the one-dimensional phased loudspeaker array, the sound beam deflection can also be used for the two-dimensional phased loudspeaker array.

When the sound beam deflection mode is adopted, the phased loudspeaker array emits sound waves obliquely upwards at an angle theta according to the sound path difference, and the delay time of each row of sound waves meets the following conditions:

Tm＝m*l₀*sin(θ)/c (3)，

where Tm is the delay time of the mth speaker unit in a line of speakers,/₀Is the length of the loudspeaker, theta is the deflection angle and c is the speed of sound. Wherein the deflection angle θ is also determined by expression (1).

It should be noted that, regardless of the one-dimensional or two-dimensional phased speaker array, and regardless of the focus deflection or the sound beam deflection, the controller may be embodied to perform control so that the speakers of the television set radiate sound wave signals to the listening environment, and the controller calculates the deflection angle θ according to expression (1) based on the received reflected sound waves, the distance D from the television set 200 to the sofa, and the distance H from the television set 200 to the ceiling, by receiving the sound waves reflected by the top surface of the listening environment and the sound waves reflected by the objects in the listening area, for example, the sound waves reflected by the ceiling and the sound waves reflected by the sofa. Furthermore, the controller can control the phased speaker array to realize focus deflection or sound beam deflection according to the deflection angle theta.

For example, if the room height is 2.8m, with the television set 1.5m from the ceiling and the sofa 3m from the television set, as shown in fig. 4, the deflection angle of the sound wave is 45 degrees. To avoid over-diffusion of the sound beam, the distance between the sofa and the television is usually adjusted to make the deflection angle θ between 15 ° and 45 ° generally good.

In addition, the speakers for radiating sound wave signals to the listening environment are not limited, and may be the above phased speaker arrays 202-1 and 202-2, or may be speakers for emitting conventional sound waves provided in the television set 200. While for receiving the reflected sound waves, it will be understood by those skilled in the art that if the speakers in the phased speaker arrays 202-1 and 202-2 are piezoelectric speakers, the functions of sound wave transmission and reception can be directly realized based on the characteristics of the piezoelectric effect. If phased speaker arrays 202-1 and 202-2 are other types of speakers, a corresponding microphone would be required to receive the reflected sound waves. The present invention is not particularly limited with respect to the specific implementation of transmitting and receiving sound waves, and the designer may make a selection as desired.

In addition, although the schematic in fig. 5b shows a two-dimensional phased loudspeaker array with a plurality of loudspeakers arranged in a rectangular pattern, such as the embodiment shown in fig. 7. The two-dimensional phased speaker arrays 702-1 and 702-2 are arranged in a rectangular or square shape, but the arrangement of the two-dimensional arrays is not limited thereto.

Alternatively, as shown with reference to FIG. 8, the two-dimensional phased speaker arrays 802-1 and 802-2 are circular arrays. Of course, it may be circular, elliptical, etc.

Accordingly, the shape of each speaker is not necessarily limited to a square piece, and may be a polygon as shown in fig. 8 and 9. The shape of the speaker is not limited, and the specific shape is determined by the layout at the time of designing or the process conditions which are easy to realize.

Of course, it should be further noted that the phased speaker array in the embodiment of the present invention refers to only a speaker array for emitting and reflecting sound waves toward a ceiling, and does not include a speaker for normally radiating sound waves directly toward a front listening area during display. It will be understood by those skilled in the art that the display device further includes one or more speakers for receiving the radiated sound waves, and the specific arrangement, structure and location are not limited in this application. Of course, external speakers placed elsewhere in the listening environment, such as the living room, may also be included to create a surround sound effect that radiates directly from the periphery of the listening area to the listener, and the present invention is not intended to be limited to the placement of such speakers.

Based on the same inventive concept, another embodiment of the present invention further provides a sound generating method of the display device, including: controlling at least one phased speaker array disposed at the display device to focus deflection or beam deflection to emit sound waves toward a top surface of the listening environment for reflection to a listening area within the listening environment.

In this embodiment, through set up the phased loudspeaker array in display device to control this phased loudspeaker array focus and deflect or sound beam deflection, thereby make the phased loudspeaker array reflect the listening area in listening environment towards listening environment's top outgoing sound wave, make the listener needn't additionally install ceiling speaker can experience the head of a user radiated sound, strengthened listener's high perception in space, satisfy the listener to the demand of top sound source surround sound, have extensive application prospect.

Optionally, in one example, controlling at least one phased speaker array disposed at the display device to focus deflection or beam deflection to emit sound waves toward a top surface of the listening environment for reflection to a listening area within the listening environment further comprises:

controlling a phased speaker array of a display device to emit a first acoustic signal;

the phased loudspeaker array receives a first reflected signal of a first sound wave signal reflected by a ceiling and a second reflected signal reflected by a sofa;

determining a first distance H between the display device and the ceiling and a second distance D between the display device and the sofa based on the first reflection signal and the second reflection signal, and calculating a deflection angle theta according to the first distance and the second distance;

determining a transmission delay of sound waves of speakers in the phased speaker array according to the deflection angle θ by based on the expression (2) or (3);

then, the controller performs control so that the array speaker array emits a sound wave signal toward the ceiling to direct the sound wave signal toward a listening area in front of the display device after being reflected by the ceiling.

Aiming at the existing problems, the invention sets a display device and a sound production method thereof, and the phased loudspeaker array is arranged in the display device, and the controller controls the phased loudspeaker array to focus and deflect or deflect sound beams, so that the phased loudspeaker array emits sound waves towards the top of a listening environment to be reflected to the listening area in the listening environment, a listener can experience head top radiated sound without additionally installing a ceiling loudspeaker, the spatial high perception of the listener is enhanced, the requirement of the listener on surround sound of an upper sound source is met, and the display device has wide application prospect.

It should be understood that the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention, and it will be obvious to those skilled in the art that other variations and modifications can be made on the basis of the above description, and all embodiments cannot be exhaustive, and all obvious variations and modifications belonging to the technical scheme of the present invention are within the protection scope of the present invention.

Claims (10)

1. A display device comprising a display screen, further comprising a controller and at least one phased speaker array comprising a plurality of speakers, the controller configured to control the phased speaker array to focus or beam deflect to emit sound waves toward a top surface of a listening environment for reflection to a listening area within the listening environment.

2. The apparatus of claim 1, wherein the speaker is a piezoelectric speaker.

3. The device of claim 2, wherein the display device is a screen-sounding display device.

4. The apparatus of claim 1, wherein the display device comprises two phased speaker arrays disposed in upper left and right regions.

5. The apparatus of claim 1, wherein the phased speaker array is a one-dimensional phased speaker array or a two-dimensional phased speaker array.

6. The apparatus of claim 5, wherein the plurality of speakers in the one-dimensional phased array of speakers are arranged in a vertical arrangement.

7. The apparatus of claim 5, wherein the plurality of speakers in the two-dimensional phased array of speakers are arranged in a rectangular arrangement or a circular arrangement.

8. The apparatus of claim 1, wherein the controller is configured to control the phased speaker array focus deflection or beam deflection by controlling speaker voicing delays in the phased speaker array.

9. The apparatus of claim 2, wherein the controller is configured to calculate a deflection angle based on the sound waves reflected from the top surface of the listening environment and the sound waves reflected from the objects in the listening area received by the piezoelectric speaker, and to control the phased speaker array to focus or deflect the sound beam based on the deflection angle.

10. A method for generating a sound from a display device, comprising:

controlling at least one phased speaker array disposed at the display device to focus deflection or beam deflection to emit sound waves toward a top surface of the listening environment for reflection to a listening area within the listening environment.

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