KR20030047585A - Panel form loudspeaker - Google Patents

Abstract

PURPOSE: A flat speaker is provided to generate effectively the vibration within a particular frequency band and improve the performance of the flat speaker by using the excitement of an edge of a flat plate. CONSTITUTION: A flat speaker includes a flat plate(40), one or more exciters(50), a frame(18), and a soft support member. The exciters(50) is fixed on an edge of the flat plate(40). The exciter(50) is used for generating the flexural vibration by exciting the flat plate(40). The frame(18) is used for fixing the flat plate(40). The soft support member is used for bonding an edge of the flat plate(40) to an edge of the frame(18). The flame(18) is formed with one selected from a group including a transparent flat plate, a semitransparent flat plate, and an opaque flat plate. The flat plate is formed with a material selected from transparent glass, polymethacrylic acid ester, polyvinylchloride, polystyrene, polycarbonate, polyethylene terephthalate. A ratio of Young's modulus to density of the flat plate(40) is 80 to 180 GPa/(G/Cm¬3). A ratio of length to thickness of the flat plate is 80 to 600.

Description

Flat Panel Speaker {Panel form loudspeaker}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a flat speaker that effectively vibrates within a specific frequency range due to excitation of a flat plate edge, thereby obtaining high-efficiency loudspeaker performance.

Most of the traditional speakers have a conical film as a speaker. This conical speaker is connected to the electromagnetic coil exciter with a relatively small end, and the conical film is rotated back and forth under the driving of the exciter. In this way, the air is driven to achieve the object of accuracy. Such speakers typically require an enclosure that prevents sound waves in front of the speaker from being interfered with by sound waves in the opposite direction from the rear, which makes the speaker heavy and generates blind spots for speech transmission. While these traditional speakers have the drawbacks mentioned above, in recent years, the demand and research of flat panel speakers have become very important with respect to the development of flat panel displays such as LCD and plasma TVs. It is. For example, Watts is a lightweight, rigid strip that uses the concept of the coincidence frequency, that is, the speed of sound waves in the air at the same frequency and the propagation speed of flexural waves on the plate. By designing a sandwich plate for the amplification of shape, a method is proposed in which the amplification plate propagates a sine wave and at the same time produces a voice of high directionality within a specific frequency range.

In addition, Heron installs a flat panel speaker using the natural vibration mode method to excite the expansion plate, uses a honeycomb sandwich panel as the expansion plate, and simultaneously excites the plate by installing an exciter at the corner of the plate. The proposed method is to improve the efficiency of speech by outputting a voice whose frequency is higher than the natural frequency and synchronization frequency of the loudspeaker plate, and simultaneously exciting a plurality of natural vibration modes. However, the flat plate designed by this method has a very large rigidity, so the loudspeaker must be driven by a large heavy exciter, so the efficiency is lower than the conventional speaker in terms of power consumption. Recently, Azima et al. Designed a flat panel speaker with a specific aspect ratio by using the method of natural vibration mode to excite the amplification plate. In this regard, a method is proposed in which most modes of the plate are excited by avoiding overlapping of the node lines of 20 to 25 natural modes in front of the plate, and the air is driven to achieve the purpose of expansion. By the way, this expansion excitation method can obtain a relatively wide voice frequency range, but the simulation transmission effect is not ideal. It is possible for a flat plate to have thousands of natural vibration frequencies and modes between 50 Hz and 20 KHz, so if the exciter is positioned on the basis of only the previous 20 or more modes, the natural mode within the range of used frequencies. The sound pressure sensitivity frequency spectrum that rises and falls low and low in a flat panel speaker designed based on this method because it causes a sudden increase in sound pressure due to excessive excitation, or a decrease in sound pressure due to overlapping nodal lines and excitation positions in a separate natural mode. This occurs and, as a result, affects the simulation transfer effect. On the other hand, this design causes these modes to be triggered when the excitation position deviates from the nodal lines of the previous 20 modes, so that in the case of the antisymmetric mode, the movement regions before and after the phases are opposite to each other. Since the sound pressures generated by each other interfere with each other, the sound pressure sensitivity is seriously affected. As can be seen from the above, there are many defects to be improved in flat panel speakers currently commercially available.

With the development of flat panel displays and the rapid development of video devices such as mobile phones and PDAs, research and demand for flat panel speakers are increasing day by day. Obviously, the design method of the flat panel speaker described above is used only for the design of the opaque flat panel speaker due to the limitation of the flat panel structure and the location of the excitation point. Therefore, in order to combine voice and video more effectively, other methods can be developed by using the battle name, partial transparency and It must be designed to be applied to opaque flat panel speakers.

In order to overcome the problems and limitations associated with the conventional flat panel speaker's vocalization and clairvoyance method, the inventors have designed a flat panel speaker of high-facsimile.

1A and 1B are front and rear views showing one excitation method of the transparent flat speaker of the present invention.

2 is a view showing another aftershock method of the transparent flat speaker of the present invention

3A and 3B are cross-sectional views of the long side and the short side, respectively, of FIG. 1, wherein the support members of the flat panel speaker edges are formed by an individual support unit made of one continuous flexible support unit and a plurality of foam rubber pads.

Figure 4 shows a separate support member for supporting a transparent plate, in which the individual support unit is a drawing made of tension wire

5 is a view of a cylindrical electromagnetic coil type exciter

6 is a view of a blade type electromagnetic coil exciter

FIG. 7 is a view of a transparent flat panel speaker using two blade-type electromagnetic coil exciters. FIG.

8 is a diagram illustrating an example in which the transparent flat panel speaker of the present invention is applied as a calculator indicator.

9 is a diagram of an example in which the transparent flat panel speaker of the present invention is applied to a TV.

10 is a view of an example in which the transparent flat panel speaker of the present invention is applied to a projection screen

11 is a view showing an example in which the transparent flat panel speaker of the present invention is applied to a mobile phone

12 is a view showing an example in which the transparent flat panel speaker of the present invention is applied to a conversation machine

13 is a view showing an example in which the transparent flat panel speaker of the present invention is applied to a video camera

14 is a view showing an example in which the transparent flat panel speaker of the present invention is applied to a PDA

<Explanation of symbols for the main parts of the drawings>

10. Transparent flat panel speaker 15. Giant transparent loudspeaker

18. Frame 30. Support member

30a. Foam rubber pad 30b. Tension wire

30c. Flexible Continuous Support Unit 31. Tension Wire

32. Push Pin 33. Rotation Button

39.Specific Points 40.Transparent Flat Plate

50. Exciter 50a. Circular oscillator

50b. Blade Oscillators 51. Wires

52,62. Ceramic Iron 53,56. Permanent magnet

53. Flexible support unit 55. Voice coil unit

56. Hemp Park Main Coil 57. Cover Plate

60. Magnet unit 70. Voice coil unit

74. Flexible support line 76. Cover plate

77. Flat coil 82. Hook

83.Soft Pad 84.Side Frame

90. TV 91. Fluorescent screen

94. Sideframe 96. Receiver

100. Projection Screen 101. Crimp Cover

102. Projectors 103. Screen

110. Mobile phone 111. LCD screen

112. Sideframe 120. Talker

121. LCD display 122. Side frame

123. Receiver 124. Pushbutton

130. Video camera 131. Display screen

132.SIDEFRAME 141.Display Screen

140.PDA 142.Sideframe

The flat panel speaker of the present invention includes a flat plate mainly used for amplification, at least one exciter positioned at a specific position of the flat plate edge, a frame for fixing the flat plate, and a support member for supporting the flat plate edge and fixed on the frame. do. The material used to manufacture the amplification plates may be any of combat, partially or opaque. This transparent transparent material is selected from, for example, glass, polystyrene (PS), polymethacrylic acid ester (PMMA), polycarbonate (PC), polyethylene terephthalate (PET), polyvinyl chloride (PVC) and the like. Also, since the excitation and support points are located on the edge of the amplification plate, the amplification plate can provide the entire viewing area. In addition, by specially designing the position of the plate edges of the exciter and the support member, the vibration waveform and the amount of vibration required when vibrating with the plate are generated, thereby generating the appropriate size and distribution of sound pressure sensitivity within the frequency range required for expansion. You can.

It is still another object of the present invention to design an effective modal parameters identification method required for a flat panel speaker by vibration mode analysis and sound pressure sensitive frequency spectrum analysis of the flat panel, thereby designing the structure of the flat panel. In addition, the present invention provides a method and program for designing a loudspeaker that determines the aftershock and support of the flat plate.

The design method and program of the amplification plate provided by the present invention are established by the effective vibration mode parameter identification method and obtained by deduction of the vibration mode analysis and the sensitivity frequency spectrum analysis of the amplification plate, and the principle thereof will be described below.

The principle of using a flat plate as a vocal source is based on driving air in contact with a plane generating flexural vibration to achieve the purpose of amplification by propagation of sound pressure after the air is compressed and expanded. . The magnitude of sound pressure generated by the plate is obtained by phonetic theory and mechanics methods. For example, in an infinitely stretched plate or in a finitely sized, enclosed plate, the sound pressure at which the vibration of the plate is generated at a point in space is obtained by Rayleigh's first integral equation as follows.

In the equation, P (r, t) is the instantaneous sound pressure where r is spaced from the plate, r is the distance between the measuring point and the reference coordinate origin of the plate, R is the distance between the measuring point and one oscillation point on the plate, r _s is The distance between the vibration point and the coordinate origin, Is the air density, t is the time, s is the area of the plate, ω is the vibration frequency of the plate, V _n (r _s , t) is the forward velocity of the vibration point on the plate, i is to be. In addition, the sensitivity of sound pressure is defined by the following formula.

Where L _p is the sound pressure sensitivity, P _rms is the square root of sound pressure, and P _ref is the reference pressure constant. By analyzing the floating vibration frequency, it is possible to obtain the sound pressure sensitivity frequency spectrum of the sound pressure sensitivity amplification plate, and to obtain a relatively uniform sound pressure sensitivity distribution within the frequency range where the human ear can hear. It becomes clear that the design is indispensable.

As can be seen from equation (1), when talking about the fixed measuring point, the magnitude of the instantaneous sound pressure is closely related to the vibration frequency ω when the plate is excited and the vibration speed V _n of the plate. In addition, when the sound pressure sensitivity frequency spectrum is designed to have a relatively uniform distribution within a specific frequency range, an appropriate velocity distribution must be generated on the surface of the plate under the action of the floating vibration frequency. Here, the origin of the reference coordinate XY is located at the center of the flat plate so that the horizontal axis X and the vertical axis Y are parallel to the long side and the cross section of the flat plate, respectively. As shown in the integral term of Equation (1), since the positive part of the velocity affects the sound pressure value obtained last, when the velocity on the plate surface is antisymmetric with respect to the reference coordinate, that is, the plate is the antisymmetric vibration waveform. It can be seen that the sound pressure generated at each point on the flat plate cancels the mutual interference degree, thereby significantly reducing the sound pressure value obtained by measuring. In addition, since the velocity distribution on the surface of the plate is related to the vibration mode, when designing the amplification plate, the vibration mode that interferes with the amplification can be identified, and appropriate adjustment can be made to contribute to the vibration of the amplification and to effectively vibrate. You must do it. In addition, the distribution on the flat surface of the velocity term of equation (1) can be obtained by combining theoretical methods, for example, finite element method and mode analysis. It is known that the lateral shift response of the plate in the mode analysis is the sum of the lateral shift responses of each mode. In other words,

Where D is the shift, n is the number of natural modes to consider, , A _i and Φ _i are the phase angle, amplitude and vibration waveform of the i th natural mode, respectively. The obtainable velocity of the time derivative with respect to D of equation (3) is expressed by the following equation (4).

As shown in Equation (4), the velocity distribution on the plate is related to the vibration mode. , A _i and Φ _i are closely related. On the other hand, as can be seen from the vibration theory, the amplitude of any mode is the magnitude of the vibration force and the position of its action, the ratio of the natural frequency and the vibration force frequency of this mode, the yaw strength of the plate, the damping value and the support method Related to factors such as If the frequency of the excitation force and the natural frequency of this mode are the same, a resonance phenomenon occurs and the amplitude of the mode approaches the maximum value. Therefore, when the excitation point is exactly positioned on the maximum shift point of the resonance mode vibration waveform, the amplitude of this mode is amplified by double, and the sound pressure sensitivity at this frequency suddenly rises. On the other hand, if the excitation point is located on the nodal line of the resonance mode vibration waveform, the resonance mode vibration waveform is rather impossible to excite, which may reduce the speed of the flat plate. Therefore, seriously affect the sound pressure value of this vibration frequency. It is a cause of influence. However, as shown in equation (4), since the amplitude of the other modes also contributes to a certain degree to the speed under this frequency, this frequency also generates the required sound pressure. Therefore, it can be seen that the vibration of the appropriate vibration mode has a significant influence on the effect of the plate amplification. The magnitude of the attenuation also affects the mode amplitude. Usually, a small attenuation contributes smallly to the amplification effect. In addition, as for the material of an amplification plate, the value of the damping ratio is suitable for 0.1 or less. The flexural strength of the plate is inversely proportional to the mode amplitude of the plate, in addition to being affected by the ratio of its elastic constant to its density, the ratio of its length and thickness, and its support method. On the other hand, the natural frequency of the plate is directly proportional to the strength of the plate. The greater the intensity, the higher the generated frequency. In addition, although the natural frequency of the mode is not directly shown in Equation (4), as described above, it affects the ratio of the natural frequency and the vibration frequency, thus affecting the amplitude of the mode. Therefore, it can be seen that natural frequency is also closely related to speed.

In general, when subjected to a vibration of a floating frequency, the natural vibration frequency of the plate has a proper distribution within the frequency range of each scale to generate a shift response that can contribute to the amplification at the natural frequency near this frequency. It is preferable. Therefore, even if the excitation point is located on the nodal line of any vibration mode, this does not cause a sudden change in sound pressure. The support for the edges of the plate directly affects its vibration mode. In particular, in the individual support elements in the support member, the mode vibration waveform of the flat plate can be changed by selecting the floating support position. As described above, certain mode vibration waveforms, such as antisymmetric vibration waveforms, for example, because the amplification plate prevents the generation of a sound pressure sensitive frequency spectrum with a relatively uniform distribution, it is appropriate to support and support the flat plate edge. By selecting the position, generation of these poor mode vibration waveforms can be avoided. The phase angle of Equation (4) relates to the attenuation, natural frequency, and vibration frequency of the flat plate, and when the flat plate attenuation value is predetermined, the phase angle can be adjusted by changing the strength of the flat plate. In summary, in a plate of known shape and area, the vibration mode parameter of the plate is closely related to its expansion effect, and it is necessary to identify an effective vibration mode in the design, and make appropriate adjustments to the mode parameter. In this way, the generation of the mode vibration waveform of the amplification is prevented. The basic parameters which have the greatest influence on the vibration mode parameters of the plate are the position of the excitation point with respect to the plate edge, the ratio of the length and thickness of the plate, the ratio of the elastic modulus and density of the material, and the method of supporting and supporting the plate edge. Location. In order to generate a sound pressure sensitivity frequency spectrum with a relatively uniform distribution within a specific frequency range on the plate, an appropriate basic parameter is selected to effectively excite the vibration mode, thereby preventing a sudden change in sound pressure sensitivity. However, in the process of determining the basic parameter values, it is necessary to analyze the vibration mode and the generated sound pressure sensitivity frequency spectrum of the plate by the identification method of the effective vibration mode parameter, thereby identifying the mode parameters that contribute to the amplification.

In recent years, optimized design methods have already been widely applied in process design. According to this optimization design method, a predetermined target can be achieved by selecting an appropriate design parameter quickly and effectively, and this optimization method is also applied to the design of the amplification plate. If you are designing a flat-panel speaker with a defined length, the design process is divided into two stages. The design goal of the first stage is to achieve maximum amplification efficiency within the design frequency range under vibration and support conditions already known in the amplification plate, in which case the design parameters of choice are the ratio of the elastic modulus and density of the material, And the ratio of the length and width of the plate. On the other hand, the design goal of the second step is to have a more uniform distribution in the sound pressure sensitivity within a specific frequency range. The target function ε is expressed by the following equation (5).

Where P _i is the sound pressure when the excitation frequency is ω _i , Is the average sound pressure, to be. The design problem at this time is to minimize ε, and the design variables are the location of the excitation point and the support point. The design goal of each of these steps is achieved by an optimization method, for example, a genetic or random optimization method.

According to the above analysis and design, in order to generate an appropriate sound pressure sensitivity frequency spectrum within the auditory frequency range of 50 Hz to 20 KHz, the ratio of elastic modulus and density of the material is preferably within the range of the following formula (6).

Where E is the elastic modulus and ρ is the density. It is preferable that ratio of the length and thickness of a flat plate exists in the range of following formula (7).

Where a is the long side of the plate and h is the thickness. The distance between the excitation on the plate edge and the edge of this edge is one tenth of the length of this side, and each side of the plate, in addition to having a continuity support unit, may again have up to two separate support points.

The above design method and the obtained design rules also apply to all designs of combat, partially transparent, and opaque flat panel speakers.

Hereinafter, with reference to the drawings will be described a preferred embodiment of the present invention.

Figure 1 shows the structure of a flat panel speaker of the present invention. The present invention is applied to flat panel speakers such as transparent, partially transparent and opaque. Hereinafter, a transparent flat panel speaker will be described as an example.

1A is a front view of the transparent flat panel speaker, and FIG. 1B is a rear view thereof. The transparent flat panel speaker 10 includes a rectangular transparent Loudspeaker plate 15, a frame hardly deformable 18, and a support member 30 for fixing the Transparent Loudspeaker plate 15 to the frame 18. The transparent loupe plate 15 includes a transparent flat plate 40 and at least one exciter 50. The length, width and thickness of this transparent amplification plate 15 are represented by a, b and h, respectively, and b is less than or equal to a. The material used for the transparent plate is a material having a transparent material, for example, glass, PMMA, PVC, PC, PS, PET, etc., in particular, the elasticity (Young's modulus) and the ratio of density to 3 to 180 GPa / (g / cm 3) It is advisable to be between. In addition, the ratio of the length and the thickness of the transparent flat plate is 80 to 600. Then, the transparent loupe plate 15 is fixed to the circumferential portion by connecting to the frame by the flexible support member (30). The support member 30 is composed of a soft continuous support unit 30c and a set of individual support units. Among them, the continuous support unit 30 is made of a corrugated rubber-containing cotton cloth, and the individual support unit is made of a high attenuation foam rubber pad 30a or a tension wire 30b, and a plurality of edges of the transparent flat plate 40 are formed. Only a specific point 39 (indicated by Xi or Yi in its position) is supported. In general, there are at most two separate supports on each side of the plate. The exciter 50 located at the edge of the transparent plate 40 is intended to be uttered by driving the transparent plate to generate vibration, and the exciter 50 is located on the long side or the short side of the plate, and the position thereof is or At the same time, or The constraints of must be met. The position on the plate edge of the exciter and the support point is determined by the effective vibration mode parameter identification method proposed by the present invention. By connecting the two electric wires 51 with the current amplifier, the exciter can control the current amplification multiplier to adjust the magnitude of the thrust (driving force) of the exciter to control the sound pressure of the speaker.

In addition, as shown in Fig. 2, the transparent flat panel speaker 10 of the present invention performs amplification by driving the transparent flat plate 40 by using two exciters 50. In FIG. 2, the two exciters 50 are located on the long side and the short side of the transparent flat plate, respectively, so that both excitation groups are generally or Under the condition of the constraint of, it is also located on the edge of any two sides of the transparent plate 40, the position of which is determined by the vibration mode parameter identification method proposed by the present invention. In addition, the method of locating the exciter on another side can be inferred from the above method. In addition, one or more exciters may be provided for each side, but how many are set depends on the length of the sides of the transparent plate.

3A and 3B show an example in which the expansion plate 15 is supported by an elastic support member 30 having a flexible continuous support unit 30c and a plurality of foam rubber pads 30a. Is a cross-sectional view in the longitudinal direction of the speaker 10, and FIG. 3B is a cross-sectional view in the width direction of the speaker 10. FIG. The foam rubber pad 30a is a high damping elastic pad, and fixes the expansion plate 15 to the edge of the frame 18. Foam rubber pad 30a acts as a disadvantage support. Up to two foam rubber pads are provided on each side of the transparent amplification plate, and the position (Xi or Yi) on the edge of the expansion plate 15 of the foam rubber pad is determined by the effective vibration mode parameter identification method according to the present invention. .

Support member 30 shown in Figure 4 is to secure the expansion plate 15 to the edge of the frame 18 by a flexible continuous support unit 30c and a plurality of tension wires (30b), each tension wire (30b) ) Has one tension wire 31, one fixing pin 32 for fixing one end of the tension wire to the transparent flat edge, and a rotary button 33 for fixing the other end of the tension wire to the frame edge. The flexible continuous support unit 30c has a function of waterproofing, dustproofing, and spinning. In addition, by rotating the rotary button 33 it is possible to adjust the tension of the tension wire, thereby adjusting the rigidity of the transparent flat plate. In a transparent flat plate having a length / thickness ratio of 100 or more, by increasing the tension of the tension wire, the rigidity of the flat plate can be clearly improved, so that the sound pressure sensitivity frequency spectrum distribution generated in the expansion plate can be adjusted. The circular exciter 50a shown in FIG. 5A is an exciter which excites the transparent flat plate 40 to obtain an amplification effect, and FIG. 5B is a cross-sectional view of the circular exciter 50a. The circular exciter 50a is composed of a permanent magnet 53, two ceramic irons 52 connected to the anode of the permanent magnet, and a voice coil unit 55, respectively. The north and south anodes are formed at the ends of both ceramic irons 52, and a horizontal magnetic field is formed between the anodes. The voice coil unit 55 includes a hollow columnar coil 56 and a tip cover plate 57 located at an upper end of the coil, which is provided with a transparent plate 40 for the exciter 50a. It sticks on the edge of and connects with the flexible support unit 54, and places the circumferential coil 56 between the north and south poles of the ceramic iron 52 in a concentric manner. Therefore, when a current flows into the electric wire 51, the voice coil unit 55 moves up and down between the two magnetic irons 52, excites and ignites the transparent flat plate 40, and amplifies.

The blade-type exciter 50b shown in FIG. 6A is an exciter which vibrates the transparent flat plate 40 to produce an amplification effect. FIG. 6B is a sectional view of this blade-type exciter, and FIG. 6C is a voice of the blade-type exciter. The structure of the coil unit 70 is shown. The blade-type exciter 50b is constituted by the magnet unit 60 and the planar voice coil unit 70 located between the gaps of the magnet unit 60. When the current flows, the voice coil unit 70 becomes the magnet unit. By moving up and down relative to 70, the transparent flat plate 40 is excited to achieve the purpose of speech. The magnet unit 60 has a pair of long rod-shaped permanent magnets 61 and respective permanent magnets 61. Four magnetic poles 62 connected to both magnetic poles N and S of the two magnetic poles, and the two magnetic poles of the two magnets are mutually inverted, and are opposed to the left and right at a small distance to each other. Between the iron pieces, magnetic fields in which the flow directions of the two upper and lower magnets are opposite to each other are formed.

The planar boil coil unit 70 is composed of a hard, thin, long end cover plate 76, a planar coil 77, and four flexible support lines 74. Among them, the tip cover plate 76 is for adhering the voice coil unit to the edge of the transparent flat plate 40, and the flat coil 77 is spread on the same plane, gradually spreading out along the hollow rectangular root. It is wound. The upper and lower sides of the quadrangle coil 77 are long sides, and the voice coil unit 70 is positioned in the middle of the gap of the magnet unit 60, and the upper and lower sides of the coil are exactly two upper, lower, left, and right sides of the magnet unit 60. It lies in the magnetic field formed by the ceramic iron piece. In addition, the other ends of the two flexible support units 74 at the two corners of the bottom of the flat coil 77 are fixed on the magnetic iron piece 62 of the bottom of the magnet unit 60, and the voice coil is moved up and down. Keep it in a vertical position.

The transparent flat panel speaker 10 of FIG. 7 excites the transparent flat plate 40 by two blade-type electromagnetic coil exciters 50b to achieve the purpose of amplification. Positions on the edge of the transparent plate 40 are the distance between the excitation center point and the left short side of the transparent plate, respectively. And Is indicated by Under conditions satisfying The value is determined by the effective vibration mode parameter identification proposed by the present invention. Also, another way of positioning the exciter on the edge is inferred based on this.

Fig. 8 shows a form in which the transparent flat panel speaker 10 of the present invention is attached in front of the screen 81 of the computer CRT monitor 80. In the figure, the frame 18 of the flat panel speaker is suspended by the plurality of U-shaped hooks 82 on the edge frame 84 of the monitor 80, whereby the frame 18 of the speaker and the edge frame of the monitor 80 are shown. A plurality of soft pads 83 are adhered between the 84 to prevent rocking of the speaker frame. The information displayed on the monitor screen 81 is transmitted to the user of the computer through the transparent flat plate 10. Since the amount of vibration generated when the transparent flat plate 40 is amplified is extremely fine, the information on the screen is not distorted.

9 shows that the transparent flat panel speaker 10 of the present invention is attached to the front of the fluorescent screen 91 of the TV 90. In the figure, the frame 18 of the flat panel speaker is suspended by the plurality of U-shaped hooks 82 on the edge frame 94 of the TV, whereby between the frame 18 of the speaker and the edge frame of the TV screen 91. A plurality of soft pads are attached to prevent the speaker frame from shaking.

10 shows that the transparent flat panel speaker 10 of the present invention is attached to the front of the projection screen 100. In the drawing, the edge frame 18 of the flat panel speaker 10 is suspended by the crimping cover 101 of the projection screen 100 by a plurality of hooks 82. The moving image projected by the projector 102 is projected onto the screen 103 after passing through the transparent flat plate 40. Thus, the voice is broadcast by the transparent speaker in front of the screen 103 directly.

11A shows that the transparent flat panel speaker 10 of the present invention is attached to the liquid crystal display screen 111 of the mobile phone 110 for communication. The user listens to the voice transmitted via the flat panel speaker 10 of the present invention and reads the information displayed on the screen 111. The voice of the user is transmitted to the outside through the receiver 96. A method of attaching the transparent flat panel speaker to the liquid crystal screen is illustrated in FIG. 11B, in which the edge frame 18 of the flat panel speaker is attached to the edge frame 112 at the periphery of the liquid crystal display screen, and as shown in FIG. 11C. , The support member 30 on the transparent flat plate 40 is directly adhered to the edge frame 112 of the screen.

FIG. 12 shows that the transparent flat panel speaker 10 of the present invention is attached to the front of the liquid crystal display screen 121 of the video intercom 120 used in a building or a home. In the drawing, the edge frame 18 of the flat panel speaker 10 is suspended from the edge frame 122 of the upper end of the liquid crystal display screen 121 of the interphone 120 by a plurality of hooks 82. In addition, a plurality of soft pads 83 are disposed between the edge frame 18 of the flat panel speaker 10 and the edge frame 122 around the liquid crystal display screen 121 to prevent rocking of the flat panel speaker 10. . The user may talk to the other party through the receiver 123 and the flat panel speaker 10. In this case, the door is opened using the pushbutton 124.

13A shows that the transparent flat panel speaker 10 of the present invention is attached on the display screen 131 of the video camera 130 or the camcorder. The user may view the subject photographed by the photographing lens 133 displayed on the display screen 131 through the transparent flat panel speaker 10 and simultaneously hear the recorded voice. The method of attaching the flat panel speaker 10 to the display screen of the video camera is attached to the edge frame 132 around the indicator of the frame 18 of the flat panel speaker as shown in FIG. As shown, there are two kinds of methods in which the supporting member 30 on the transparent flat plate 40 is directly adhered to the back surface of the edge frame 132 around the display screen.

14A shows that the transparent flat speaker 10 of the present invention is attached to the touch display screen 141 of the PDA 140. The transparent plate 40 is spaced apart from the proper distance so as not to contact the amplification display screen, which should be a distance that the transparent plate 40 can be deformed and contact the display screen 14 when data is input.

As shown in Fig. 14B, the transparent flat panel speaker 10 is attached to the edge frame 142 of the PDA display screen as shown in Fig. 14B. As described above, there are two types of methods in which the supporting member 30 on the transparent flat plate 140 is directly adhered to the rear surface of the edge frame 142 around the display screen.

Naturally, the flat plate according to the present invention is not limited to the transparent flat plate, and the partially transparent or opaque flat plate may also be implemented and used based on the above-described structure and method.

The technical idea of the present invention is not limited to the above-described embodiments, and any of simple design changes and modifications made by those skilled in the art without departing from the appended claims belong to the technical scope of the present invention.

According to the present invention, the vibration mode analysis and the sound pressure sensitivity frequency spectrum analysis of the amplification plate provide an identification method of the effective vibration mode parameters required for the plate speaker, thereby designing the structure of the amplification plate, and the excitation and support of the plate. You can decide.

Claims (12)

In the method of designing and manufacturing a flat panel speaker including an amplification flat plate, (1) analyzing the vibration mode of the amplification plate and identifying the analysis of the effective mode parameters; (2) performing sound pressure sensitivity frequency spectrum analysis of the flat panel speaker using the vibration mode analysis result, and identifying design parameters affecting sound pressure sensitivity frequency spectrum distribution; (3) designing a flat panel speaker by selecting appropriate design parameters to generate the required sensitivity and distribution within a specific frequency range; (4) fabricating a flat panel speaker based on the selected design parameters. Flat panel speaker design method characterized in that provided. The method of claim 1, wherein the amplification plate of the flat speaker is selected from the group consisting of a transparent amplification plate, a partially transparent amplification plate, and an opaque amplification plate. 2. The flat panel speaker of claim 1, wherein the flat panel speaker comprises a loudspeaker plate, a frame that is not easily deformed to fix the marspan plate, and a softness that connects the multiplicity of flat edges and a plurality of specific support points on the edges to the frame edges. With a supporting member, The amplification plate is a transparent amplification plate consisting of a transparent plate and at least one exciter positioned at an edge of the transparent plate, wherein the transparent plate is amplified by driving the exciter positioned on the flat edge. How to. 4. The parameter for generating a sound pressure sensitivity frequency spectrum required for a flat panel speaker includes: a ratio of elastic modulus and density of the transparent flat plate, a ratio of length and thickness of the transparent flat plate, and support points and excitations on the expansion plate edges. Contains the position of the flag, At least one exciter is attached to four sides of the transparent plate, and at the same time there are two or less support points on each side of the pair. 4. The method of claim 3, wherein the parameters for designing the flat panel speaker are divided into two stages, and the first stage is such that the transparent amplification flat plate can obtain the maximum amplification efficiency under constant excitation and support conditions. The ratio of the elastic modulus and density of the plate and the ratio of length and thickness are designed, and the second step is to determine the sound pressure sensitivity distribution necessary for the planar loudspeaker within a specific frequency range. Design the location on the transparent plate edge of the exciter and the support points based on the properties, And the ratio of Young's modulus and density of the transparent flat plate is between 80 and 180 GPa / (g / cm 3), and the ratio of length and thickness is between 80 and 600. In the flat panel speaker which generates vibration and expands, (1) reputation and (2) at least one exciter fixed on the edge of the plate, which excites the plate to generate urine vibration; (3) a frame that is not easily deformed to fix the genital plate, (4) A flat panel speaker comprising a flexible support member for connecting the edge of the flat plate and a plurality of specific points on the edge to the frame edge. The method of claim 6, wherein the flat plate is selected from the group consisting of a transparent plate, a partially transparent plate, and an opaque plate, The material of the flat plate is selected from transparent glass, polymethacrylic acid ester (PMMA), polyvinyl chloride (PVC), polystyrene (PS), polycarbonate (PC), polyethylene terephthalate (PET), and the Young's modulus and And the ratio of the density is between 80 and 180 GPa / (G / cm 3), and the ratio of the length and thickness of the plate is between 80 and 600. 7. The excitation plate according to claim 6, wherein the flat plate is a transparent flat plate, and the excitation unit that excites the transparent flat plate is an electromagnetic coil exciter, a circular exciter having a cylindrical coil, and a blade type exciter having a flat coil. It is divided into species, among which the blade type electromagnetic coil exciter (1) a pair of long permanent magnets finely spaced at the same time that a pair of magnetic poles are opposite to each other; (2) two iron pieces are placed on the upper ends of the left and right permanent magnets, respectively, and the gap between the two iron pieces is a magnetic iron piece having a magnetic field flowing to the right; (3) two iron pieces are placed at the upper ends of the left and right permanent magnets, respectively, and the gap between the two iron pieces is a ceramic iron piece having a magnetic field flowing from left to right; (4) a flat coil having a hollow long rectangular shape in which the upper and lower sides are long sides, and the left and right sides are short sides, (5) By sticking with the surface of the transparent plate, the plane coil is vertically fixed on the edge of the transparent plate, and the lines on both sides of the plane coil are positioned in the upper and lower magnetic fields respectively formed by both magnets. With flat end cover plate, (6) A flat panel speaker comprising a plurality of flexible support lines for vertically holding the planar coils positioned in the magnetic field formed by the upper and lower magnetic iron pieces. According to claim 8, The manufacturing method of the planar coil is of two types: the line method of directly winding the line wound along one square root, and the printed circuit board method of printing a metal line on the film, In the flat panel speaker, the flexible support member for supporting the transparent expansion plate edge is composed of a continuous support unit and an individual support unit to flat plate speaker, characterized in that to secure the transparent plate to the frame. 10. The method according to claim 8 or 9, wherein the continuous support unit is made of a corrugated rubber-containing cotton cloth for waterproofing, spinning, and dustproofing, and the individual supporting unit is made of a plurality of foamed rubber pads having viscosity, and transparency Each ream of flat plate has a maximum of 2 foam rubber pads, and a plurality of tension wires that can adjust the tension by rotation of the rotary button. A flat panel speaker comprising two kinds of wires with up to two tension wires and a rotary button attached thereto. In a transparent flat panel speaker having both transparency and loudspeaker power, (1) a transparent flat plate that is transparent and is expanded by urine vibration; (2) at least one exciter adhered to the edge of the transparent flat plate, (3) a frame for fixing the transparent flat plate, (4) A transparent flat panel speaker comprising a flexible support member for fixing the transparent flat plate on an edge of a frame. 12. The method of claim 11, wherein the transparent flat panel speaker is applied to the monitor by a plurality of hooks, the transparent flat panel speaker is suspended in front of the fluorescent screen of the monitor, and the plurality of viscous software is disposed between the frame of the flat panel speaker and the edges around the screen. There is a way to prevent the rocking of this flat speaker by putting a pad, The transparent flat panel speaker may be applied to a TV screen by using the plurality of hooks to suspend the transparent flat speaker in front of the TV screen, and having a plurality of viscous soft pads between the frame of the flat panel speaker and an edge around the screen. There is a way to prevent the soft pad rocking, In the method of applying the transparent flat panel speaker to the projection screen, the transparent flat panel speaker is suspended in front of the screen by the plurality of hooks, and a plurality of viscous soft pads are placed between the frame of the flat panel speaker and the edges around the screen. There is a way to prevent the shaking of the speaker, In the method of applying the transparent flat panel speaker to a mobile phone for communication, the transparent flat panel speaker is placed in front of the liquid crystal display screen of the mobile phone, and the adhesive frame is integrally bonded to the frame of the flat panel speaker and the edge frame around the liquid crystal display screen. And the edge frame around the liquid crystal display screen as the frame of the flat panel speaker, and the flat support speaker is suspended between the display screen and the edge frame around the flat panel by a flexible support member. In the method of applying the transparent flat panel speaker to the video interphone, the plurality of hooks hang the frame of the transparent flat panel in front of the interphone fluorescent screen, and a viscous soft pad is placed between the frame of the flat panel speaker and the edge around the interphone fluorescent screen. There is a way to prevent the fluctuation of this flat panel speaker, The method of applying the transparent flat panel speaker to a video camera includes a method of directly attaching the frame of the flat panel speaker to the edges around the LCD display screen of the video camera, and the flexible flat panel is connected to the liquid crystal display screen by a flexible support member. There are two types of fixing between the edges around the display screen, The method of applying the flat panel speaker to a PDA includes directly attaching the frame of the transparent flat panel speaker to the frame of the liquid crystal display screen of the PDA, and attaching the transparent flat panel speaker to the liquid crystal display screen and the display screen by the flexible support member. A transparent flat speaker comprising two types of fixing between the edges of the circumference.