TW201140394A - Indicated position detecting apparatus and indicated position detecting method - Google Patents

Abstract

An indicated position detecting apparatus includes a display module having a display screen, and a plurality of microphones to detect a contact sound to the display screen. The plurality of microphones each are arranged separately around an outer peripheral portion of the display screen. A time difference acquisition unit acquires arrival time differences of the contact sound between two microphones in each of two combinations of the plurality of microphones. A positional information acquisition unit derives a hyperbola based on each of the arrival time differences acquired by the time difference acquisition unit, each hyperbola having focal point corresponding to the arrival time differences between the two microphones in each of the two combinations of the plurality of microphones, and acquires an intersection of the two derived hyperbolas as a position information where the contact sound is generated.

Description

201140394 VI. Description of the invention: [Reciprocal reference of related application] The present invention is based on the prior art of the application of the application of the patent application No. 2009-238796, filed on November 6, 2009 Japanese Patent Application No. 2009-254511, the entire disclosure of which is hereby incorporated by reference in its entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire entire all TECHNICAL FIELD OF THE INVENTION The present invention relates to a technique for detecting an indicated position on a display screen. [Prior Art] In the related art, a device such as an LCM (Liquid Crystal Panel Module) or a CRT (Cathode-ray tube) is used to indicate an arbitrary position in the display screen of the display device. Membrane type touch panel. In the resistive film type touch panel, for example, a film is adhered to a surface of a glass surface as a substrate, and a transparent electrode grid called IT0 (Indium Tin Oxide) is provided on an opposing surface of both the glass and the film. structure. In the touch panel, when the surface of the film side is pressed by a pen or a finger, the ITO is turned on at a position corresponding to the position, and therefore the position can be detected by measuring the voltage of the resistance portion corresponding to the indicated position (for example, Japan) JP-A-2009-48653). In a resistive film type touch panel, it is indispensable to cover a display screen of a display device by a film provided with an electrode grid. This tends to cause a decrease in display characteristics such as LCM. [Invention] The aspect of the pointing position detecting device of the present invention includes: a display module having a display screen; and a plurality of microphones disposed apart from each other at an outer peripheral portion of the display screen to detect the display screen a contact sound acquisition unit that acquires a time difference of arrival of the contact sound between the two microphones for a combination of two types of microphones, and a position information acquisition unit that performs each of the foregoing by the time difference acquisition unit The arrival time difference is derived, and a hyperbola with the aforementioned microphone corresponding to the arrival time difference is derived as a focus, and an intersection of the two derived hyperbolas is obtained as position information for generating the contact sound. Further, another aspect of the pointing position detecting device of the present invention includes: a display module having a display screen; and a plurality of microphones disposed apart from each other on an outer peripheral portion of the display screen, and detecting from the display screen a command sound emitted by the three-dimensional space; a time difference acquisition unit that acquires an arrival time difference of the instruction sound between the two microphones for the combination of the three types of microphones; and a position information acquisition unit that obtains the time difference acquisition unit by the time difference acquisition unit Each of the acquired arrival time differences is derived from a hyperboloid having the microphone corresponding to the arrival time difference as a focus, and the intersection of the three hyperboloids derived is used as position information for emitting the indication sound. Further, the aspect of the indication position detecting method of the present invention includes a time difference obtaining step of combining two types of microphones, and acquiring two microphones of a plurality of microphones disposed apart from each other on the outer peripheral portion of the display screen. a difference in arrival time between the aforementioned contact sounds to detect a contact sound for displaying a display screen in the 201140394 module; and a position information obtaining step of deriving each of the aforementioned arrival time differences obtained in the time difference obtaining step The hyper-curve of the microphone corresponding to the arrival time difference is used as a hyperbola of the focus, and the intersection of the two hyperbola derived is obtained as position information for generating the contact sound. Further, in another aspect of the indication position detecting method of the present invention, the time difference obtaining step includes a combination of four kinds of microphones, and two microphones of four microphones disposed apart from each other on the outer peripheral portion of the display screen are obtained. a difference in arrival time between the contact sounds to detect a contact sound with respect to a display screen in the display module; and a position information obtaining step of deriving each of the aforementioned arrival time differences obtained in the time difference obtaining step The hyperbola of the aforementioned microphone corresponding to the arrival time difference as a focus acquires position information for generating the aforementioned contact sound based on the derived hyperbola. Further, 'one of the other aspects of the pointing position detecting method of the present invention includes a time difference obtaining step' which combines three types of microphones and acquires two microphones among a plurality of microphones which are disposed apart from each other on the outer peripheral portion of the display screen a difference in arrival time between the aforementioned indicator sounds, to detect an indication sound emitted from a 3-dimensional space on the display screen in the display module; and a position information acquisition step 'in accordance with each of the foregoing steps obtained by the aforementioned time difference obtaining step The arrival time difference is derived, and a hyperboloid with the aforementioned microphone corresponding to the arrival time difference is derived as a focal point, and the intersection of the three hyperboloids derived is obtained as position information for emitting the indication sound. 201140394 Further, the pointing position detection according to the present invention includes a time difference obtaining step of acquiring a three-dimensional space information obtaining step on the display screen of the four types of the arrival sounds of the indicator sounds disposed between the outer peripheral microphones of the display screen. According to the aforementioned arrival time difference, the hyperboloid with the gram wind as the focus is derived according to the position information of the aforementioned indication sound. Advantages of the Invention The advantages of the present invention will be apparent from the following description, or the advantages of the present invention may be inserted in the form of the following embodiments, and constitute an embodiment of the present specification, together with the above general description and The elements of the invention. [First Embodiment] Hereinafter, a first embodiment of the instruction position detecting device according to the embodiment of the present invention will be described. The second dimension plane on the display screen of the display screen of the LCM1 indicating the position detection or image of the embodiment is described. The indication position detecting device is composed of: lcmi, one of the other aspects of the m measurement method is a combination of microphones, and obtains a difference between two of the four microphones of each other to detect an indication sound emitted from the display mode; And the above-mentioned wheat-derived hyperboloid acquisition corresponding to each time difference obtained in the position difference obtaining step is explained, and some advantages will be learned by the implementation of the present invention. This issue and combination are implemented and obtained. BRIEF DESCRIPTION OF THE DRAWINGS The following drawings illustrate the following embodiments of the invention in detail. Fig. 1 is a view showing the configuration of the embodiment of the present invention. The device is used to detect any position indicated by the displayed text. That is, the detection position is used as the indication position. It is composed of four microphones 2A, 2B, 2C, and 2D (see FIGS. 2A and 2B) on the display screen side of the LCM 1, and an amplifier 3, an A/D converter 4, and a position acquisition unit 5. The LCM1 transmission type shown in Fig. 1 has two transparent glass substrates 11 and 12 on the front side and the back side, and liquid crystals 13 sealed between the two glass substrates 11 and 12, and attached to the glass substrate 1 respectively. 1, polarized plates 14, 15 outside the outer surface. A pattern of transparent pixel electrodes 16 is formed on the inner surface of the back glass substrate 12, and a portion corresponding to the pixels in the pixel electrodes 16 is formed with a 'TFT (Thin Film Transistor) 17. On the inner surface of the glass substrate 11 on the front surface side, a color filter 18 having a predetermined color arrangement and a transparent common electrode 19 are sequentially laminated to form a pattern. The periphery of the polarizing plate 14 on the front side is covered by a frame cover 20 on which an opening of the display window 20a is formed. In the following description, an area recognizable by the display window 20a on the display surface of the LCM 1 (the surface of the polarizing plate 14 on the front side) is referred to as a display screen 1a of the LCM 1. When the LCM 1 is used, a surface light source composed of a light guide plate or a backlight is provided on the back surface of the polarizing plate 15 on the back side. Further, a transparent protective cover may be provided in the display window 20a as needed. Further, the display screen la is formed in a rectangular shape. On the other hand, the four microphones 2A' 2B, 2C, and 2D constituting the pointing position detecting device are disposed inside the display window 20a. Fig. 2A is a layout view of the respective microphones 2A, 2B, 2C, and 2D of the display screen 1a of the LCM 1. In the following description, each of the microphones is distinguished by referring to each of the microphones 2A, 2B, 2C, and 2D as the first to fourth microphones. As shown in Fig. 2A, the first to fourth microphones 2A to 2D are arranged on the respective sides of the display screen 1a so as to be located outside the display screen 1a. Specifically, the first to fourth microphones 2A to 2D are orthogonal to the center Q of the rectangular display screen 1a, and exist on a plane parallel to the display screen la, that is, in the same plane as the display screen la. The two straight lines L and Μ are arranged in pairs. In other words, the first and third microphones 2A and 2C are arranged in pairs on a straight line L parallel to the long side of the display screen 1a, and the second and fourth microphones 2B and 2D are arranged on the short side of the display screen la. The other parallel lines are arranged in pairs. Next, the first to fourth microphones 2A to 2D are individually detected at different positions, and the indication sound generated by the arbitrary indication position of the display screen 1a illustrated in the second figure is output as an analog sound signal to the amplifier. 3 0 The first to fourth microphones 2 A to 2D detect the sounds indicated by the predetermined stylus 30 shown in Fig. 1, or the tip or fingertip of any type of pen type. The sound produced on the surface of the display screen la when abutting. In other words, the indicator sounds detected by the first to fourth microphones 2A to 2D are the contact sounds generated on the display screen la or the vicinity of the display screen la when the pointer indicates an arbitrary position on the display screen 1a. Wherein, the 'stylus 30 includes, for example, a sensor or a switch for sensing, for example, a contact with the display screen la; and a small speaker or a buzzer, etc. On the front end side of the display screen 1a, when the front end portion is sensed to abut on the display screen la, a periodic sound is emitted as the 201140394 contact sound. The amplifier 3 amplifies the analog audio signals output from the first to fourth microphones 2A to 2D, and the A/D converter 4 converts the audio signal amplified by the amplifier 3 into a digital signal. The position acquisition unit 5 is configured by, for example, a microcomputer including a CPU (Central Processing Unit), a peripheral circuit such as an input/output interface, a memory in which a predetermined program is stored, and a work memory, and also functions as a time difference acquisition unit 5a of the present invention. And the function of the location information acquisition unit 5b. Further, the position obtaining unit 5 obtains an output signal (audio signal) from the first to fourth microphones 2A to 2D converted into a digital signal by the A/D converter 4, and obtains the sequence by the hyperbola method described later. The indicated position information of the source of the indication sound detected by the first to fourth microphones 2A to 2D is indicated, and the obtained instruction position information is supplied to another device. As shown in FIG. 3, the position information acquired by the position acquisition unit 5 sets the specific angle of the display screen 1a (the lower left corner in FIG. 3) to the coordinates of the XY coordinate system of the origin 0 (0, 0). Position (X, y). The position acquisition unit 5 supplies an arbitrary object to the position information, and is, for example, a personal computer that controls the information (character or video) displayed by the LCM 1. Next, the order of obtaining the coordinate position (X, y) in the position obtaining unit 5 will be described. The position acquisition unit 5 periodically acquires changes in the sound pressure level in the output signals in the first to fourth microphones 2A to 2D (which can also be fixedly obtained). Fig. 4A is a diagram showing the change of the sound pressure level in the output signals of the first to fourth mics-10·201140394 wind 2A to 2D when the indication sound is detected, and the horizontal axis is the time 'the vertical axis is the sound pressure level quasi. In addition, the sound pressure level is based on the sound pressure level in a specific frequency band of the output signal in the pre-imaginary indicator sound. Then, as shown in FIG. 4A, when the sound pressure level in each of the microphones of the first to fourth microphones 2A to 2D is peaked with a slight time difference, that is, when the indicator sound is detected, The difference in arrival time of the indicator sound between the microphones paired with each other as previously described is obtained. In other words, the time difference obtaining unit 5a acquires the arrival time difference tAC of the indicator sounds in the first and third microphones 2A and 2C and the arrival time difference tBD of the indicator sounds in the second and fourth microphones 2B and 2D. Specifically, the time difference acquisition unit 5a counts the elapsed time from an arbitrary time point, and the elapsed time when the third microphone 2C detects the indication sound (the time at which the sound pressure level exhibits a peak) is The elapsed time of the time when the first microphone 2A detects the indication sound is subtracted, and the arrival time difference uc of the first and third microphones 2A and 2C is obtained. Therefore, the source of the arrival time difference Uc of the first and third microphones 2A and 2C is the source of the indication sound (the indication position P), and when it is closer to the first microphone 2A than the third microphone 2C, as shown in FIG. When it is positive, it is negative when it is closer to the third microphone 2C than the first microphone 2A. In addition, the time difference acquisition unit 5a acquires the second and fourth microphones 2B and 2D by subtracting the elapsed time when the second microphone 2B detects the indication sound by the elapsed time when the fourth microphone 2D detects the indication sound. Side -11 - 201140394 arrival time difference tBD. Therefore, the arrival time difference tBD of the second and fourth microphones 2B and 2D is 'the source of the instruction sound (instruction position P) is closer to the second microphone 2B than the fourth microphone 2D as illustrated in Fig. 3 The time is positive, and conversely, when it is closer to the fourth microphone 2D than the second microphone 2B, it becomes negative. The arrival time difference tAC on the side of the first and third microphones 2A and 2C indicates the difference in distance to the indication position P in each of the microphones. Similarly, the arrival time difference tBD on the second and fourth microphones 2B and 2D is the same. The difference in distance to the indicated position P in each microphone is indicated. That is, the absolute time 乘 of the arrival time difference (tAC:, tBD) of the indicator sound between a set of microphones multiplied by the speed of sound is the distance difference to the indicated position P between a group of microphones. The point at which the difference between the distances from the first and third microphones 2A and 2C is constant is present on the hyperbola having the focus of both of the microphones 2A and 2C, and is similarly spaced from the second and fourth microphones 2B and 2D. A point where the difference in distance is a certain point exists on the hyperbola with both microphones 2A, 2C as the focus. Therefore, as shown in FIG. 4B, a hyperbola (hereinafter referred to as a first hyperbola) which is close to the side of the indication position p among the hyperbolas 1 〇 s and i 0t focusing on the first and third microphones 2A ' 2C is taken. The intersection of the hyperbola (hereinafter referred to as the second hyperbola) 20s near the indication position P among the hyperbola 20s and 20t focusing on the second and fourth microphones 2B and 2D is the indication position P. One of the hyperbola i〇s, i〇t and the other hyperbola 20s, 20t shown in Fig. 4B is only for convenience of display, and the shape or positional relationship of the hyperbola is actually different. •12- 3 201140394 In the XY coordinate system, the hyperbola of the two focal points on the x-axis is set to 2a from the distance between the two focal points and the hyperbola, and the distance between the two focal points is set to When 2c, it is represented by the following formula (1).

(where b2 = c2-a2) On the other hand, since the distance (L,) between the first and third microphones 2A and 2C is known, it is known from the above formula (1) that if it is to the indicated position P The distance difference is set to 2a, and the hyperbola 10s and 10t having the first and third microphones 2A and 2C as the focus can be expressed by the following formula (2). (xk/2)2 (y~Ly/2?. ax2 = ax =(l/2)C〇tAc ...(2) cx = Lx/2 ^ = ^°χ2-3χ2 Here, C. is The sound speed, Uc is the arrival time difference. Similarly, since the distance (L,) between the second and fourth microphones 2B and 2D is known, it is known from the above formula (1) that the distance difference to the indicated position P is obtained. In the case of 2a, the hyperbola 20s and 20t having the second and fourth microphones 2B and 2D as the focus can be expressed by the following formula (3). -13- 201140394 (X-LJ2) 2 (y-Ly/2) 2 By2 ay2 3y = (l / 2)C〇tgD Cy = Ly/2 by — ^Cy~ 3y' (3) Here, UD is the arrival time difference. Therefore, the position of the indicated position (X) as the source of the indication sound The position (y) on the y-axis can be obtained by calculating the equation (5).

Ay2 + bx2

VbxV-ax2V +U/2 ax2 + bv2 pxV-ax2ay2 + Ly/2 In addition, in the above formula (4), when a is positive and the difference tAC is positive, the 第 of the first term on the right side is smaller than (According to the calculation result, the position (x) on the first hyperbola l〇s close to 2A shown in Fig. 4B can be obtained. Conversely, the arrival time difference t AC is negative .. The first item on the right /2), therefore, the position (X) on the hyperbola l〇t close to the third microphone 2C can be obtained as a result of the calculation. Similarly, in the above formula (5), when a, the following equations (4), ... (4) (5) of the positive 値P on the}c axis, that is, L»/ 2 when arriving, the first microphone ® a X is negative 値, 値 will be greater than (L, S 4 B is shown in the figure - that is, when the arrival time -14.201140394 difference Ud is positive, the first item on the right side will be less than (Ly / 2) Therefore, in the calculation result, the position (y) on the second hyperbola 20s close to the second microphone 2B shown in Fig. 4B can be obtained. Conversely, when &, is negative, that is, the time difference of arrival When tBD is negative, the 第 of the first term on the right side is larger than (L, /2), so the page ' can be obtained as close to the position on the hyperbola 20t of the fourth microphone 2D shown in FIG. 4B ( In the position acquisition unit 5, the time difference acquisition unit 5a acquires the arrival time difference (tAC, tBD) of the indication sound between the plurality of microphones, and then uses the position information acquisition unit 5b to calculate the expression (4). Equation (5), thereby obtaining the first hyperbola 10s with the first and third microphones 2A, 2C as the focus and the second and fourth microphones 2B, 2D as shown in FIG. 4B The coordinate position (X, y) of the intersection of the second hyperbola 20s which is the focus. That is, the coordinate position (X, y) of the arbitrary indication position P is obtained. Then, the position acquisition unit 5 takes the obtained coordinate position ( X, y) is supplied to the other device as the pointing position information. That is, the pointing position detecting device according to the first embodiment includes a display module having a display screen, and a plurality of microphones are arranged separately from each other. The outer peripheral portion of the display screen is for detecting a contact sound to the display screen; the time difference acquisition unit is configured to obtain a difference in arrival time of the contact sound between two microphones; The part 'derives a hyperbola 'focusing on the microphone corresponding to the arrival time difference to obtain the intersection of the two derived hyperbolas as the pre-production -15- according to each of the aforementioned arrival time differences obtained by the time difference acquisition unit. 201140394 The position information of the contact sound is described. Next, in the instruction position detecting device according to the first embodiment, the display screen 1 of the LCM 1 is instructed by the stylus pen 30 or the like. In the arbitrary position of a, the first to fourth microphones 2A to 2D detect the pointing sound generated at the pointed position p, and the pointing position P is specified based on the arrival time difference of the pointing sound between the microphones that are paired with each other. Since it is not necessary to cover the display screen 1a with other members, the indication position in the display screen 1a can be detected without lowering the display characteristics of the LCM 1. Further, in the practice of the present invention, the description will be described in the embodiment. The configuration of the pointing position detecting device and the like are changed as follows. For example, two straight lines L and Μ which are orthogonal to each other in the first to fourth microphones 2A to 2D are arranged, and may not necessarily exist in the same plane. The two straight lines L and Μ may also exist in different planes parallel to each other. In addition, the two straight lines L and Μ may exist in different planes that are not parallel to each other. Further, as described in the present embodiment, it is convenient to calculate the coordinate position (X, y) at the position Ρ when the two straight lines L and Μ are orthogonal, but the display screen is at least projected on the display screen 1a. It is sufficient to form a cross in la. Further, as shown in Fig. 5, the first to fourth microphones 2A to 2D may be disposed at respective corners of the display screen 1a. In other words, the first to fourth microphones 2A to 2D may be arranged in pairs on a straight line L1 including one diagonal line of the display screen 1a and on a straight line M1 including another diagonal line. Further, the setting units -16 - 201140394 of the first to fourth microphones 2A to 2D in the LCM 1 are. The indicator sound generated in the vicinity of the display screen 1a or the display screen 1a can be sensed when the pointer instructs any position on the display screen 1a, and can be appropriately changed. In other words, the first to fourth microphones 2A to 2D can be disposed at any position on the outer peripheral portion of the display screen 1a as long as they are separated from each other. Further, in the present embodiment, the hyperbola (the first hyperbola l〇s) having the first and third microphones 2A and 2C as the focus and the pair of the second and fourth microphones 2B and 2D as the focus are detected. The intersection of the two different hyperbolas of the curve (the second hyperbola 20 s) is used as the indicated position in the display screen la. However, the two hyperbola which are different in the calculation target of the coordinate position (X, y) of the intersection point (indicating the position P) may be the first and fourth microphones 2A and 2D as shown in FIG. The hyperbola of the focus 30s, 30t, and the hyperbola 40s, 40t with the second and third microphones 2B, 2C as the focus. In other words, the combination of a set of microphones to be hyperbolically calculated can be appropriately changed, for example, 'the arrival time difference of the indication sounds in the first and fourth microphones 2A and 2D, and the second and third microphones 2B, The arrival time difference of the indicator sound in 2C is to specify the indication position P. In addition, one of the hyperbola 30s, 30t and the other hyperbola 40s, 40t shown in Fig. 6 is the same as that shown in Fig. 4B. For convenience, the shape or positional relationship of the hyperbola is It's actually different. In addition, the combination of a set of microphones which are hyperbolic calculation targets is not shown in FIG. 5, and the first to fourth microphones 2A to 2D are arranged in the respective corners of the display -17-201140394 screen la. The same can be used in any combination. Further, the position obtaining unit 5 can obtain the coordinate position of the arbitrary pointing position P by the following processing different from the present embodiment when the pointing sound is detected by adding the function as the control unit and the correcting unit in the present invention. (X, y ) ° For example, the position obtaining unit 5 performs the coordinate position (X, y) of the intersection (indicating position P) of the two hyperbola shown in FIG. 4B in the order described in the embodiment. The calculation result is obtained as the processing of the first indication position information. Then, the position obtaining unit 5 changes the combination of the microphones which are one of the hyperbolic calculation targets to another combination shown in FIG. 6, and calculates the two different pairs according to the same principle as the present embodiment. The coordinate position (X, y) of the intersection of the curve (indicating position P). In other words, the position acquisition unit 5 calculates the difference between the arrival time difference between the first and fourth microphones 2A and 2D and the arrival time difference between the second and third microphones 2B and 2C. The coordinate position (X, y) of the intersection of the hyperbola (indicating the position P), and the calculation result is obtained as the processing of the second indication position information. Then, the position obtaining unit 5 calculates the X coordinate of the point located in the middle of the X coordinate and the second indicated position information in the first indicated position information, and obtains the calculated knot. The frozen coordinate is the corrected X coordinate. At the same time, the position obtaining unit 5 calculates the y coordinate of the point in the middle of the Y coordinate in the first indicated position information and the y coordinate in the second indicated position information, and obtains the calculation result as the corrected y coordinate. In other words, the position acquisition unit 5 performs -18 - 201140394 to correct the first indication position information by the second indication position information, and obtains the corrected X coordinate and the corrected y coordinate as the third indication position information. Then, the position acquisition unit 5 supplies the coordinate position (X, y) obtained as the corrected third position information to the other device as the final instruction position information. As described above, the first indication position information and the second indication position information are obtained by converting the combination of the group microphones which are the hyperbolic calculation targets, and the acquired first indication position information is corrected by the second indication position information. By obtaining the final indication position information (the third indication position information), the detection accuracy of the indication position in the display screen 1 a can be improved. Further, in the present embodiment, a configuration in which the detection position is detected using four microphones will be described. However, the number of microphones provided on the outer peripheral portion of the display screen 1a may be three. When three microphones are used to detect the position of the indication, for example, the first group composed of the first microphone and the second microphone and the second group composed of the first microphone and the third microphone may be used. Two sets of microphone pairs are constructed as hyperbolic calculation objects. Further, in the present embodiment, the coordinate position (X, y) of the Χ γ coordinate system is used as the indication position information indicating an arbitrary indication position on the display screen 1a. However, when the present invention is implemented, only one set of microphones separated from each other may be disposed on the outer peripheral portion of the display screen 1a, and the representation may be determined based on the information of the hyperbola with a set of microphones as the focus. The information indicating the position of any indicated position in the screen 1 a is displayed as -19-201140394 as the indicated position information indicating the arbitrary indicated position. As the information indicating the position which can be judged based on the information of the hyperbola with a set of microphones as the focus, it is, for example, information indicating that any of the indicated positions is located in any of the upper and lower half regions of the display screen 1a. Or, the information indicating that any of the indicated positions is located in any of the left half area and the right half area of the display screen la. Further, as information indicating a schematic position that can be determined based on information of a hyperbola having a set of microphones as a focus, for example, when the display screen 1a is divided into a plurality of squares in the vertical and horizontal directions, it indicates that there is any indicated position. Information about the specific squares (multiple squares) of the possibility. In addition, the position obtaining unit 5 described in the present embodiment can be realized by, for example, a configuration including any device including the LCM 1, and can be realized by a microcomputer or the like included in any device (including a personal computer). Further, the indicator sounds detected by the first to fourth microphones 2A to 2D may have characteristics in a frequency band of an audible range, or may have characteristics in a frequency band of a non-audible range. Further, in the present embodiment, the pointing position detecting device for detecting an arbitrary pointing position on the display screen of the LCM 1 is described. However, the present invention may be used in addition to the LCM 1 in a display screen of another display device such as a CRT. Detection of any indicated position. [Second Embodiment] Fig. 7 is a schematic configuration diagram showing a second embodiment of the pointing position detecting device of the present invention. The embodiment of the present embodiment is an example of the case where the pointing position detecting device of the present invention is applied to the LCM 51 that protects the display screen by the cover -20-201140394 cover 60. As shown in Fig. 7, the LCM 51 is a transmissive type in which the liquid crystal panel 52 is attached to the polarizing plates 14 and 15 on the front and back sides of the liquid crystal panel 52, and the brightness of the polarizing plate 15 is attached to the back side. The lift film 53 is configured such that the surface of the polarizing plate 14 on the front side is covered by the protective cover 60. Although not shown in FIG. 7, the liquid crystal panel 52 is composed of two transparent glass substrates 1 1 and 1 described in the first embodiment, and liquid crystals 13 and pixels provided between the two glass substrates 1 and 12. The electrode 16, the TFT 17, the color filter 18, and the common electrode 19 are formed. The brightness enhancement film 53 is, for example, a PET (Poly Ethylene Terephtalate) film in which an acrylic resin is laminated, and the light emitted from the surface light source formed by a light guide plate or a backlight (not shown) is collected to increase the brightness of the liquid crystal panel 52. Upgrade. The polarizing plate 14 attached to the surface side of the liquid crystal panel 52 has a configuration as shown in Fig. 8A, Fig. 8B or Fig. 8C. For example, as shown in Fig. 8A, the polarizing plate 14 has a three-layer structure in which TACCTri Acetyl Cellulose films 14b and 14b are attached to the PVA (poly Vinyl Alcohol) film 14a to which polarizing performance is applied, and is reinforced. Next, the agent J4e is connected to the liquid crystal panel 52 and the protective cover 60. Further, for example, as shown in FIG. 8B, the polarizing plate 14 has a two-layer structure in which the back surface of the PVA film 141 to which the polarizing performance is applied is adhered to the TAC film 14b to be reinforced, and the liquid crystal is cured by the transparent adhesive I4e. Panels 52 and -21 - 201140394 protect the cover 60 in a subsequent configuration. Further, for example, as shown in FIG. 8C, the polarizing plate 14 has a three-layer structure in which a PVA film 14a and a reinforcing TAC film 14b which impart polarizing performance are sequentially attached to the phase difference plate 14c, and a liquid crystal is bonded by a transparent adhesive 14e. The panel 52 and the protective cover 60 are constructed next. The protective cover 60 is, for example, a transparent plate made of glass or plastic, and is attached with a polarizing plate 14 on the surface side. Further, the protective cover 60 is fixed to the body or the casing of any device provided with the LCM 51, and has an area larger than the surface of the polarizing plate 14. Then, in the present embodiment, the first and third microphones 2A shown in FIG. 7 are adhered to the back surface of the peripheral edge portion 60a of the protective cover 60 on the outer side of the peripheral edge of the polarizing plate 14 on the surface side. 2C, and 4 microphones composed of the 2nd and 4th microphones not shown in Fig. 7. The position of the four microphones on the plane is the same as that of the first embodiment, and is located at the center of each side of the display screen of the LCM 51 (the surface of the polarizing plate 14 on the front side) (see FIG. 2A). However, the four microphones are arranged in pairs on two straight lines which are on the same plane facing the back side of the display screen (the surface of the polarizing plate 14 on the front side) of the LCM 51. Further, in the present embodiment, the instructions are also configured by four microphones including the first and third microphones 2A and 2C, an amplifier 3 to which four microphones are connected, an A/D converter 4, and a position acquisition unit 5. Position detection device. The amplifier 3, the A/D converter 4, and the position acquisition unit 5 have the same configuration and function as those of the first embodiment. -22-201140394 In the present embodiment, the arbitrary position of the display screen of the LCM 51 is set by the peripheral portion 60a of the protective cover 60 when the position of the display screen of the LCM 51 is indicated by the pointing finger or the fingertip. Four microphones on the back to detect the indicator tone. Next, the position acquisition unit 5 calculates a coordinate position (X' y) belonging to the instruction position information indicating the source of the indication sound by the same method as in the first embodiment. Therefore, it is not necessary to cover the display screen of the LCM 5 1 with a film provided with an electrode grid, and the indication position on the display screen can be detected without deteriorating the display characteristics of the LCM 51. According to the present embodiment, even when four microphones are provided on the back surface of the peripheral edge portion 60a of the protective cover 60, the four microphones can be placed on the outer peripheral portion of the display screen of the LCM 51 as in the first embodiment. Anywhere. For example, four microphones can also be placed at each corner of the display screen (see Fig. 5). In addition, the four microphones may not necessarily be arranged in the same plane. Further, as shown in the present embodiment, even when four microphones are provided on the back surface of the peripheral edge portion 60a of the protective cover 60, the position obtaining unit 5 calculates the coordinate position (X, y) indicating the source of the sound generation. The specific calculation method can employ various calculation methods described in the first embodiment. Further, the position obtaining unit 5 may obtain the indicated position described in the first embodiment as the indicated position information indicating the source of the indication sound. Further, the number of microphones provided on the back surface of the peripheral edge portion 60a of the protective cover 60 may be three. On the other hand, in the LCM 51 shown in the present embodiment, the liquid crystal panel 52 is protected from the impact caused by the fingertip of the stylus 30 by protecting the cover 630-201140394 cover 60. Therefore, in the case of constituting the liquid crystal panel 52, a thin type having a thickness of about 0.7 mm to 0.5 mm can be used. The cover 60 can ensure a thickness of about 0.20 mm, and can be protected. When, for example, the thickness of the polarizing plates 14 and 15 is 0.17 mm and the film 53 is 0.06 mm, the entire protective cover 60 and the LCM 51 become 2.0 mm to 1.60 mm. about. [Third Embodiment] In the first embodiment and the second embodiment, the position indicated by the second-order plane on the display screen is used as an instruction. However, in the following third embodiment, the space where the screen overlaps is indicated. That is, the case where the position indicated by 3 is indicated as the indicated position on the display screen will be described. FIG. 9 shows a portable information terminal 100 having a configuration as a pointing position detecting device or a display device. The portable information terminal 100 includes various functions such as a schedule management function reference function and a pen input function. As shown in FIG. 9, the length of the portable information terminal 100 is provided on the surface of the main body 102: a horizontally long display unit 103 for displaying various information such as text information, a power button 104, and an operation portable information. The plurality of operations l〇5e used by the terminal 100. Further, a glass substrate of the first or the like or the like is provided on the outer peripheral portion of the display unit 103. Further, the LCM 51 is secured. The brightness can be increased by the thickness of the thin body, and the configuration of the position in the display element space can be determined for the case where the position is detected. , dictionary, etc. "The following structure. Body 102 is horizontal or video information and the user is working as a key 1 0 5 a~ 4th microphone-24- 201140394 6 A to 6 D. Fig. 10 shows the schematic structure of the display unit 103 The portion 103 is constructed by the LCM 31 capable of color display: two transparent glass substrates 3 and 3 3 on the front side and the back side, and liquid crystals 34 between the glass substrates 3 2 and 3 3 are respectively attached to the sky. The polarizing plate 3 5 and 36 on the outer surface of the third surface, the light-guiding plate 37 provided on the back side, and the light-reflecting sheet 38 are provided. The outer peripheral portion of the 37 (not shown) is provided with an LED (light source such as light ei) A pattern of the poles 39 is formed on the inner surface of the glass substrate 33 on the back side, and the TFTs 40 are formed corresponding to the pixels in the pixel electrodes 39. The color filters 4 1 arranged on the inner surface of the glass substrate 32 on the front side are transparent. The common electrode 4.2 is patterned. The periphery of the polarizing plate 35 on the front side of the LCM 31 is covered by the frame cover 43 on the surface. The opening of the display window 43a of the polarizing plate 35 of the frame cover 43 is arranged in the display window. 1 to 4th microphones 6A to 6D. In addition, at the end 100, on the display surface of the LCM 31 (on the side of the table) The rectangular area recognized by the display window 43a is a display screen. The first to fourth microphones 6A to 6D are orthogonal to the center QQ of the face 31a of the ninth figure, and are displayed and displayed on the display screen plane. The same cross-sectional view of the screen 31a is shown. The LCM3 1 system is sealed in the back surface of the two glass substrates 32 and the plate 36, and the transparent pixel portion of the light guide plate has a predetermined color. The surface layer is formed to form the surface of the body 2 having the inner side portable information end plate 35 exposing the front side 4 3 a) • 3 1 a. ° • shown, in the plane where the display 3 1 a is parallel -25· 201140394 The straight lines LL and MM are arranged in pairs, that is, the first and third microphones 6A and 6C are arranged in pairs on the straight line LL parallel to the long side of the display screen 31a, and the second and second microphones are arranged in pairs. The fourth microphones 6B and 6D are arranged in pairs on the other straight line MM parallel to the short side of the display screen 31a. The first zero figure is a cross-sectional view along the straight line LL. The first to fourth microphones 6A to 〜 6D is used for individual detection by the piggybacking information terminal 100 The instruction sound emitted by the stylus pen 70 shown in Fig. 10. The stylus pen 70 is used when the user inputs text information or the like using the pen input function of the portable information terminal 100, and is provided with: The pen type main body 71 and the small push button switch 72 provided on the circumferential surface of the main body 71. The push button switch 72 is an automatic recovery type that maintains the operating state only during the pressing by the user. Inside the main body 71 (not shown) of the stylus pen 70, a small power supply and a small speaker or a buzzer including a front end portion of the main body 71 and generating an instruction sound when the push button switch 72 is pressed are built therein. The indicator sound generation circuit of the sound emitting unit. Next, the stylus pen 70 is operated to periodically emit an instruction sound of a specific frequency band at a constant time interval (n times/second) while the push button switch 72 is being pressed. Fig. 1 is a schematic block diagram showing the electrical configuration of the portable information terminal 100. The portable information terminal 100 includes a control unit 151, a ROM (Read Only Memory) 152, a flash memory unit 153, a key input unit 154, a drive circuit 155, and a signal processing unit 156. The LCM 31 is connected to the drive circuit 155 at -26-201140394, and the first to fourth microphones 6A to 6D are connected to the signal processing unit 156 via the amplifier 157. The control unit 151 is composed of a CPU (Central Processing Unit) and its peripheral circuits. The control unit 151 controls the operation of the portable information terminal 100 according to various control programs stored in R 0 Μ 1 5 2, and can also function as the time difference acquisition unit 1 5 1 a and the position information acquisition of the present invention. Part 1 5 1 b function. The control program is an essential software (OS: Operating System) that is indispensable for the control of the portable information terminal 100, and a plurality of application software for realizing the functions of the portable information terminal 100. In addition to the above control program, ROM 1 5 2 also stores various materials such as dictionary materials. The flash memory 1 5 3 system is a non-volatile semiconductor memory that stores setting data of the mobile information terminal 1 or the text information input by the user. The key input unit 154 is a plurality of operation keys 105a to 105e shown in Fig. 9, and supplies an operation signal generated in response to an operation key operated by the user to the control unit 151. The driving circuit 15 5 generates a driving signal for driving the LCM 31 according to the command of the control unit 151, and supplies the generated driving signal to the LCM 3 to cause the display screen 31a to display predetermined text information or image information. The signal processing unit 156 converts the output signals of the first to fourth microphones 6A to 6D amplified by the amplifier 157, that is, the analog audio signals into digital signals, and performs filtering processing such as noise removal, and filters- 27- 201140394 The processed audio signal is supplied to the control unit 1 51. Next, in the portable information terminal 100, when the user uses the pen input function, the first to fourth microphones 6A to 6D detect the pointing sound emitted by the stylus pen 70, and the control unit 151 obtains The indicated position information indicating the position is indicated as the indicated position of the display position 3 1 a of the transmission position of the indication sound indicated by the user. The instruction position information acquired by the control unit 151 indicates an arbitrary position in the three-dimensional space. That is, the indication position information is the coordinate position P(x, y, z) of the orthogonal coordinates as shown in Fig. 1 2 A, and the lower left corner of the display screen 31a' is set to the origin (0, 0, 0). Further, the long side of the display screen 31a is set to the X axis, and the coordinate position when the short side of the display screen 31a is set to the y axis. Here, Fig. 12B is a view showing coordinate positions of the first to fourth microphones 6A to 6D in the XY plane in the orthogonal coordinates. Next, a method of obtaining the indicated position information in the control unit 151 will be described. When the stylus 70 emits an instruction sound at an arbitrary position, the pointing sound is transmitted in various directions at a constant speed (sonic speed). In this case, when there is a difference in the distance from the transmission position of the instruction sound to the respective microphones of the first to fourth microphones 6A to 6D, if any two microphones are set as one set, the indicator sound is set between the respective groups of microphones. The arrival time will vary. Fig. 13A is a convenient display showing the change of the sound pressure level in the output signals of the first to fourth microphones 6A to 6D at the time of occurrence of the indication sound, and the arrival of the indication sound in each microphone of the predetermined complex array microphone. A diagram of the time difference. In Fig. 13A, the horizontal axis is time and the vertical axis is the sound pressure level, and the time point (tA, tB, U, tD) at which each of the -28-201140394 sound pressure levels reaches the peak is the first to fourth microphones 6A. The detection timing of the indication sound in ~6D is the timing at which the indication sound arrives in the present embodiment. Further, the sound pressure level is a sound pressure level in a predetermined frequency band of the indication sound emitted by the stylus pen 70. Further, in Fig. 13A, the arrival time difference between the indication sounds of the microphones formed by the first and third microphones 6A and 6C is tAC, and the second and fourth microphones 6B and 6D are similarly formed. The arrival time difference of the indicator sound between the group microphones is Ud, and the arrival time difference between the indicator sounds of the group of microphones formed by the first and fourth microphones 6A, 6D is U. . Next, by multiplying the arrival time difference (Uc, tBD, tAD) of the indication sound between the respective sets of microphones by the speed of sound, a distance difference from the transmission position of the indication sound between the respective sets of microphones can be obtained. Here, the point in the space which is spaced apart from the first and third microphones 6A and 6C by a certain distance is present in a hyperboloid (double-leaf hyperboloid) focusing on the first and third microphones 6A and 6C. Similarly, a point in a space having a predetermined distance from the second and fourth microphones 6B and 6D exists in a hyperboloid having the second and fourth microphones 6B and 6D as focal points. Further, a point in a space which is spaced apart from the first and fourth microphones 6A, 6D by a distance is present in a hyperboloid having the first and fourth microphones 6A, 6D as a focal point. Therefore, the intersection of the respective hyperboloids with each group of microphones as the focus is the position of the transmission of the indication sound, that is, the indication position with respect to the display screen 3 1 a . That is, the 1 3 B-picture shows a -29-201140394 slit, that is, a hyperbola, when each hyperboloid having each group of microphones as a focus is cut in a plane parallel to the display screen 31a. As shown in Fig. 13B, the first hyperboloid (hyperbolic) l〇P, 1〇Q' with the first and third microphones 6A and 6C as the focus is the second and fourth microphones 6B and 6D. The intersection of the two hyperboloids (hyperbolic) 20p, 20q, and the third hyperboloid (hyperbolic) 30p, 30q with the first and fourth microphones 6A, 6D as the focus becomes the pointing position P. In addition, the 13B chart is only for the convenience of displaying each hyperboloid (hyperbolic), and the shape or positional relationship is different from the actual one. On the other hand, each hyperboloid with the focus of each group of microphones can be obtained by the following formula (6). Said. However, the equation (6) is a general expression when the focus is present on the z-axis. X2 y2 z2 . _?w1 (8) Further, since the distance (Lx) between the first and third microphones 6A and 6C is known, if the distance difference to the pointed position p is 2ai, the above equation ( 6) The following equation (7) can be obtained as a numerical expression indicating the first hyperboloids 1〇p and 1〇q focusing on the third and third microphones 6A and 6C. (x-L-x/2)2 (y-Ly/2]P 22 ax2 ~= 1

Ax = (l/2)C0tAC ^k=Lx/2 ."(7) ________ 丄.... -30- 201140394 Similarly, 'the distance between the 2nd and 4th microphones 6B and 6D (L,) is known' Therefore, when the distance difference to the pointing position p is 2a, the following equation (8) can be obtained as the second hyperboloid 2 indicating that the second and fourth microphones 6B and 6D are the focal points. The formula of 〇p, 20q. (X-LJ2)2 (y-Ly/2)2 22 Γ~2 Τ~2 ΓΤ = -1 ay by by ay =(l/2)C〇tBD ...(8) cy =Ly/2 by one ay2 another On the other hand, it is assumed that the first and fourth microphones 6 A and 6D are located on the X-axis, and the first microphone 6A is located at the origin (〇, 〇, 〇), and the distance between the first and fourth microphones 6A and 6D is set to When the distance difference from the pointing position p is 2a, the distance (x) is obtained by the above formula (6), and the following equation (9) is obtained as a imaginary representation with the first and fourth microphones 6A and 6D as the focus. The number of hyperboloids. X2 Y2 z2 -2--9--0=1 axy bxy bxy

Axy = (1/2)C0tAD __ ...(9) cxy = (V4^Lx2+Ly2 "..... bxy =^xy2-axy2 In addition, the coordinate position of each point of the hyperboloid existing on the above imaginary (X , y' z) If the following formula (10) is used for conversion, it can be converted into the actual third hyperboloids 30p, 30q with the focus of the -31-201140394 1 and the fourth microphones 6 A, 6D as the focus. Coordinate position (X, y, ζ) β X COS0 - sin0 0, , Χ, 'Lx/4, y = sin0 COS0 0 Y + 3Ly/4 0 , Ζ; , 〇, 0 = tan_1(Ly/Lx) - (10) Therefore, the following equation (11) can be obtained from the equations (9) and (10) as a mathematical expression indicating the first and fourth microphones 6A and the third hyperboloids 30p and 30q as the focal points. cos2 θ sin2 0 y2 [2 2 ) a 2 b 2 V axy Dxy JX + kaxy Dxy ) cos0.sin0.xy cos20 sin2〆xy

A〆 16aJ b,

Lxcosg^ 3Ly sin0 2a 2b, y 16b xy b xy Therefore 'satisfy the coordinate positions (X, y, Z) of all equations (7), (8), and (11) with each set of microphones as the focus of each pair The intersection point of the curved surface becomes the transmission position of the indication sound, that is, the coordinate position (X, y, z) with respect to any indication position P of the display screen 3la ^ but 'for example, if the arrival time difference of each group of microphones (tAC, tBD) , ) When there is an error, 'the distance difference (2ax ' 2 a, ' 2a, y ) between the positions of the indication sounds between the microphones of each group also produces an error, so -32- 201140394 cannot be satisfied. (7) The coordinate position (X, y, z) of the equations (8) and (11). Therefore, in the control unit 151, the coordinates of the arbitrary indication position P are obtained by using the following formula (12). Position (X, y, z), which indicates position information" n = {F(x, y, z)f + {G(x, y, z)}2 + {H(x, y, z)} 2 where F(x, y, z) = (left) - (right) of equation (6) G(x, y, z) = (left) - (right) of equation (6) H (x, y , z) = (left) - (right) of equation (6) (12) above (1 2 ) When there is no error in the distance difference (2a»> 2ay, 2aiy) obtained from the arrival time difference (Uc, tBD, tAD ) of each group of microphones and the position of the indication sound between each group of microphones, the calculation result ( η) becomes a discriminant of 0 (specific 値). The specific sequence when the control unit 151 obtains the position information is as follows. That is, in the control unit 151, coordinates ((, 〇, 〇) to (Lx, L, 'L:) are sequentially substituted in the coordinates 値 (X, y, ζ) of the above formula (1 2 ). The calculation result (η ) is obtained separately. Here, the z coordinate (Lz) in the coordinate 値 (匕, Ly ′ L:) is predetermined as the maximum coordinate position of the detection range in the z-axis indicating the position. In other words, the control unit 15 is in the coordinate 値(X, y' z) of the equation (1 2 ), and sequentially substitutes the coordinates 各 of each point in the three-dimensional space in a certain range above the display screen 31a. The operation result (η ) is output. In the case of -33-201140394, the control unit 151 obtains the coordinate 値(χ, y, z) when the calculation result (n) is the minimum as the indication position information. However, in the portable information terminal 100, three types of operation modes, such as a soft key mode, a brush mode, and a line drawing mode, are prepared in advance as an operation mode for using the pen input function, and when the pen input function is used, the user can set any desired as needed. Action mode. The soft key mode is an operation mode prepared for inputting characters or symbols, and the brush mode and the line drawing mode are operation modes prepared for inputting a line drawing. then,. In the portable information terminal 100, when the three types of operation modes are set, the control unit 151 also functions as the time difference acquisition unit 15 1 a and the position information acquisition unit 15 1 b of the present invention, and It also functions as the display control unit 151c and the input processing unit 151d. Hereinafter, the operation content of the specific acquisition order of the indicated position information by the control unit 151 when the pen input function is used by the user in the portable information terminal 100 will be described. (Soft Key Mode) First, the operation of the portable information terminal 100 when the user sets the soft key mode will be described. Fig. 14 and Fig. 15 are flowcharts showing the processing contents of the control unit 151, and Fig. 16 shows the operation of the stylus pen 70 in the soft key mode setting, and the touch 潷. An explanatory diagram of an example of a change in display content in the display face 31 a' of the LCM 31 operated by 70. As shown in Fig. 14, the control unit 151 starts the operation while setting the soft key mode, and first starts the detection operation of the -34-201140394 indicating sound by the stylus pen 70, and makes the LCM 31 The display screen 31a displays the first soft key 501 (step SA1). Here, the detection operation of the indicator sound sequentially confirms the movement of the sound pressure level of the output signal in the first to the first of the winds 6A to 6D, and the moving portion 151 is the plural point at the start of the detection operation of the instruction sound. The arrival of the indicator sound in each microphone of the group microphone counts the count of elapsed time used. Further, the soft key 501 is composed of a plurality of operation buttons. Each of the operation keys of the soft key 501 is pre-assigned with a plurality of symbols such as an English period. The initial key 015 displayed in step SA1 is displayed with one of the respective operation letters or symbols for each operation button. That is, as shown in Fig. 16, "Kj, "P", "U", "Z" are displayed. In addition, although the illustration is omitted in Fig. 16, each of the operation buttons 501a constituting the soft key 501 in Fig. 17A indicates the guide characters of the other English numbers assigned to the respective operation buttons 501a ("A". ~E", "Ζ·,", etc.) are displayed in small letters. On the other hand, in the respective operation button pressing directions (the opposite directions of the z-axis direction) constituting the soft keys 501, a plurality of operation positions are imaginarily provided, and the specific English letters of the divided operation buttons 501a are assigned at the operation positions of the respective stages. Or one of the tokens. For example, the button 50 1 a is supposed to have a 5-stage operation position, such as the 4th chip in Figure 16. Before the system, the image of the time difference, or the point or state of the soft button of the English A", "F", the letter shown in the figure is written in letters or in the above English 501a, in the same stage in the same operation 1 7 B-35-201140394 shows that "A" is assigned to the first layer operation position of the operation button 501a to which "A to E" is assigned, and is assigned to each of the operation positions of the second layer to the fifth layer. "B" ~ "E". In other words, the control unit 151 displays the alphabets or symbols assigned to the first layer operation positions of the respective operation buttons 501a by the respective operation buttons 501a of the soft keys 50 1 in the initial state. In the following description, the English letters and symbols assigned to the respective layer positions of the operation buttons 501a are referred to as characters or the like. After the processing of step S A 1 is performed, the control unit 151 confirms whether or not the indication sound of the stylus pen 70 has been detected (step SA2). In other words, the control unit 151 sequentially confirms whether or not the sound pressure level of the output signals of the first to fourth microphones 6A to 6D is peaked with a slight time difference. Next, when the control unit 151 can confirm that the sound pressure level of the output signals of the first to fourth microphones 6A to 6D exhibits a peak time with a slight time difference (step S A2 : YES), it is judged that the indication can be detected at that time point. The sound, by the method described above, obtains the indicated position information indicating the indicated position of the source of the indication sound, that is, the coordinate position (X, y, z) in the orthogonal coordinates shown in FIG. 12A (step SA3) . Fig. 15 is a flow chart showing the order of obtaining the position information in the control unit 151. When the instruction position information is acquired, the control unit 151 sets the time point at which the sound pressure level of the output signals of the first to fourth microphones 6A to 6D is peaked as the point at which the indication sound arrives in each microphone. Next, the control unit 151 subtracts the elapsed time (tA) when the first microphone 6A reaches the finger-36-201140394 when the first microphone 6A reaches the time indicated by the elapsed time (tc) at the time when the third microphone 6C reaches the instruction sound. The arrival time difference Uc of the indication sounds in the first and third microphones 6a and 6C is obtained (step SA1〇1). Further, the control unit 15 1 obtains the second time by subtracting the elapsed time (tB) at the time when the second microphone 6B indicates the arrival of the sound by the elapsed time (tD ) of the time when the fourth microphone 6D indicates the arrival of the sound. And the arrival time difference tBD of the indicator sounds in the fourth microphones 6B and 6D (step SM〇2). In addition, the control unit 15 1 obtains the first time by subtracting the elapsed time (ta ) at the time when the first microphone 6A indicates the arrival of the sound by the elapsed time (tD) of the time when the fourth microphone 6D indicates the arrival of the sound. And the arrival time difference tAD of the indication sound in the fourth microphones 6 A, 6D (step SA103). Next, the control unit 151 sets the coordinate positions of (Lx, Ly, L:) in order to be the coordinate position of any point in the orthogonal coordinates shown in FIG. 12A ( The processing of X, y, z) (step SA104), the equation (1 2 ) of the discriminant described above, substituting the set coordinate position (X, y, z), and in steps SA101 to SA103 The obtained arrival time difference (tAC >tBD>tAD)> of each group of microphones is obtained, and the calculation result (η) is obtained (step SA105), and the obtained calculation result (n) and the set coordinate position (X, y) are obtained. , ζ ) corresponds to the billion in the internal memory (step SA106). Thereafter, the control unit 151 repeats the processing of steps SA104 to SA106 until the coordinate position (X, y, ζ) becomes (L«, L, Lz) (step SA107: NO). Next, the control unit 15 1 stores the calculation result (η) when the coordinate position (X, y, z) is substituted (L, L, Lz) (step SA107: Yes), -37-201140394 The coordinate position (x, y, z) at the time of obtaining the minimum 値 operation result (η) in the total operation result (η) of the memory obtains the confirmed coordinate position (; (, y, z) as a coordinate indicating the indicated position The position, that is, the position information is indicated (step SA108), wherein the specific processing order of the coordinate position (X, y, ζ) obtained by obtaining the operation result (n) of the equation (12) becomes the minimum 为 is arbitrary. The control unit 151 returns to the processing shown in FIG. 14 after acquiring the coordinate position (X, y, ζ) as the pointing position information, and confirms that it corresponds to the acquired coordinate position (X, y, ζ). Whether the pointed position (x, y) in the display screen 3 1 a is within the button area (step SA4). That is, the control unit 151 confirms the position indicated by the obtained coordinate position (X, y, ζ). Whether the coordinate position (X, y) of the XY plane is included in any of the operation keys 5 0 1 a constituting the soft key 501 When the indication position (X, y) in the display screen 31a is not in the button area (step SA4: NO), the control unit 15 1 returns to the processing of step SA2 without doing anything. When the indication position (X, y) in the display screen 3U is within the button area (step SA4: YES), it is also confirmed whether the operation button corresponding to the indication position (X, y) is the operation button that is already selected. (Step SA5) At the beginning of the process, even if the pointed position (X, y) in the display screen 3 1 a is in the button area, the operation button corresponding to the pointed position (X, y) is not the selected operation. The control unit 151 first reversely displays the character or the like (the character-38-201140394 or the symbol of the first layer operation position) in the position corresponding to the pointed position (x, y). The operation button is used as the selected operation button, and the predetermined button identification information indicating the operation button is recorded in the internal memory (step SA6). Further, the control unit 151 is to be in step SA3. Acquired seat The z coordinate of the position (X, y, z) is stored as the reference position in the z-axis direction (height direction) after being stored in the internal memory (step SA7), and immediately returns to the processing of step SA2. Therefore, the user is pressing, for example, a push button switch. When the front end portion of the stylus pen 70 is moved toward the upper side of the "A to E" operation buttons in the state of 7.2, the operation buttons of "A to E" are memorized as the selected operation buttons, and as shown in FIG. In the state I, the character of the "A" of the first layer is displayed in reverse. At the same time, the position of the front end portion of the stylus pen 70 in the vertical direction is recorded. Next, the control unit 151 acquires a new coordinate position (X, y, z) every time the instruction sound is detected (step SA2: YES) (step SA3). Next, when the new coordinate position (X, y, z) is acquired in step SA3, the control unit 151 sets the instruction position (X, y) in the display screen 31a in the button area (step SA4: YES). However, when the operation button corresponding to the indicated position (x, y) is not the selected operation button, that is, when the operation button corresponding to the indicated position (X, y) is changed to another operation button (step SA5: No), The processing of steps SA6 and SA7 is performed again. In other words, the control unit 151 is an operation button or the like that reversely displays the character being displayed on the position corresponding to the new instruction position (X' y), and uses the operation button as the selected operation button to indicate the operation. The key recognition information of the button pre-39-201140394 is memorized in the internal memory (step SA6). Further, the control unit 151 stores the Z coordinate of the newly acquired coordinate position (X, y, z) as the reference position in the Z-axis direction in the internal memory (step SA7). Therefore, when the user presses the push button switch 72, for example, when the front end portion of the stylus pen 70 is moved from the operation button to which "A to E" is assigned to the operation button to which "K to 0" is assigned, " The operation button of K to ◦ is memorized as the operation button being selected, and as shown in the state II of Fig. 16, the character of the "K" of the first layer is reversely displayed. At the same time, the position of the front end portion of the stylus pen 70 in the vertical direction is memorized. Further, when the new coordinate position (X, y, z) is acquired in step SA3, the control unit 151 sets the instruction position (X, y) in the display screen 31a in the button area (step SA4: YES). Further, when the operation button corresponding to the indicated position (X, y) is the selected operation button (step SA5: YES), it is confirmed whether or not there is a change in the z coordinate (step SA8). If there is no change in the z coordinate (step S A8: NO), the control unit 151 immediately returns to the processing of step SA2. Further, when the control unit 151 changes the z coordinate (step SA8: YES), the control unit 151 subtracts the new z coordinate 値 from the z coordinate stored as the reference position, thereby calculating the indicated position (indicative sound). The amount of movement of the reference position stored in step SA7 downward is the amount of movement in the lower position (step SA9). In the process of step SA9, the control unit 151 sets the amount of movement to 〇 when the amount of movement is negative. Then, the control unit 51 confirms whether or not the character or the like in the reverse display is a character or the like of the operation position (layer position) determined in advance by the amount of movement calculated in step SA9 by -40 - 201140394 (step SA10). In addition, the amount of movement and the position of the layer are increased by a certain amount each time the movement amount is increased, and the operation position is increased by one layer. Then, if the character or the like in the reverse display is a character or the like of the layer position corresponding to the calculated movement amount (step SA10: YES), the control unit 151 returns to the processing of step SA2 without doing anything. Conversely, if the display is reversed. When the character is not the character of the operation position corresponding to the calculated movement amount (step SA10: NO), the control unit 151 changes the character or the like in the reverse rotation to the character of the operation position corresponding to the movement amount, etc. (step SA11), temporarily returns to the process of step SA2. Therefore, when the user presses the push button switch 72 to move the front end portion of the stylus pen 70 upward toward the operation button to which "K 0 0" is assigned, the front end portion of the stylus pen 70 is directed toward the display screen 3 1 When the a side (lower side) is moved by a predetermined amount, as shown in the state III of Fig. 16, the character in the reverse rotation is changed from "K" to "N", for example. On the other hand, the control unit 151 does not have an instruction sound during the process of repeating the processing of step SA2 and subsequent steps (step SA2: NO), and the state in which the indication sound cannot be detected continues for a predetermined time or longer, that is, the stylus is continued. When the transmission interval of the indicator sound in 70 is longer than the predetermined time (step SA12: YES), the following processing is performed. First, the control unit 151 checks whether or not the indicated position (X, y) in the previous display screen 3 1 a is within the button area (step SA13). Next, -41 - 201140394 When the previous instruction position (X, y) is in the button area (step SA13: YES), the control unit 151 displays the character or the like in the selected operation button display on the display screen 31a. A predetermined character input area (step SA14). That is, input processing of text information is performed. Therefore, if the user stops the operation of pressing the push button switch 72 to stop the occurrence of the indicator sound in the state shown in the state III of the sixth embodiment, the user displays the screen 31a as shown in the state IV of Fig. 16. Enter the text of "N" in the predetermined text input area. Further, when the control unit 151 is in the processing step SA13, when the previous instruction position (X, y) is not in the button area (step SA13: NO), after the soft key 501 is initialized, the soft key 501 is restored to After the same initial state as that displayed in step SA1 (step SA), the process returns to step SA2. Thereafter, the control unit 151 repeatedly executes the processing in and after step SA2 while the user releases the soft key mode. As described above, when the soft key mode is set in the portable information terminal 100 when the pen input function is used, the user uses the stylus pen 70 to input a desired character or the like. (brush mode) Next, the operation of the portable information terminal 100 when the user sets the brush mode will be described. Fig. 18 is a flowchart showing the processing contents of the control unit 151, and Fig. 19 is a view showing the operation of the stylus pen 70 in the brush mode setting and the display screen 31a of the LCM 31 in response to the operation of the stylus pen 70. An illustration of an example of a change in the display content in 42-201140394. As shown in Fig. 18, the control unit 151 starts to operate at the same time as the setting of the brush mode, and first starts the detection operation of the indication sound emitted by the stylus pen 70, and the thickness (line width) of the line to be drawn is drawn. The predetermined reference thickness is set (step SB 1 ). Further, the detection operation of the indicator sound is the same as in the case of the soft key mode, and the control unit 151 starts counting the arrival of the indicator sound in each microphone of the complex array microphone described above when the detection operation of the instruction sound starts. The elapsed time used in the calculation of the time difference. After the processing of step SB1 is performed, the control unit 151 sequentially confirms whether or not the instruction sound of the touch pen 70 has been detected (step SB2). In other words, the control unit 151 sequentially confirms whether or not the sound pressure level of the output signals of the first to fourth microphones 6A to 6D is peaked with a slight time difference. Next, the control unit 151 can confirm the first to fourth microphones 6A. When the sound pressure level of the output signal of the ~6D is peaked by a slight time difference, it is determined that the indicator sound can be detected at the time point (step SB2: YES), and the indication belonging to the indication is obtained by the processing shown in FIG. The position information indicating the position of the sound generation source, that is, the coordinate position (X, y, z) in the orthogonal coordinates shown in Fig. 12A (step SB3). Next, the control unit 15 1 confirms whether or not the coordinate position (X, y) of the XY plane displayed by the acquired coordinate position (X, y, z) is in the position on the display screen 31a (step SB4). If the pointed position (X, y) is not in the display screen 31a (step SB4: -43 - 201140394 No), the control unit 151 returns to the processing of step SB2 without doing anything. When the instruction position (X, y) is within the display screen 31a (step SB4: YES), the control unit 151 further confirms whether or not the drawing is in progress (step SB5). Further, the confirmation of the step S B 5 is performed by confirming whether or not the internal memory has a drawing flag to be described later. At the beginning of the process start, even if the pointed position (X, y) is within the display screen 31a, it is not in the state of drawing (step SB5: NO). Therefore, the control unit 151 first counts the z coordinate of the coordinate position (X, y, z) acquired in step SB3 as the reference position in the z-axis direction (height direction) in the internal memory (step S B 6 ). Further, the control unit 151 stores the indicated position (X, y) in the display screen 3 1 a as the drawing position in the internal memory, and sets the drawing flag indicating the drawing (step SB7). In addition, the setting of the flag is to depict the processing of the flag in the internal memory. Then, the control unit 151 displays the start point at the instruction position (X, y) in the display screen 31a (step SB8), and temporarily returns to the process of step SB2. That is, when the user presses the push button switch 72 while the front end portion of the stylus pen 70 is positioned above the desired position of the display screen 31a, as shown in the state I of FIG. The starting point S is displayed at the desired position of 3 1 a. At the same time, the indication position (X, y) in the display screen 3 1 a and the position in the upper and lower directions of the front end portion of the stylus pen 70 are memorized. Next, the control unit 151 acquires a new coordinate position (X, y, z) every time the instruction sound is detected (step SB2: YES) (step SB3). Next, -44 - 201140394 When the control unit 15 1 acquires a new coordinate position (χ, y, z) in step SB3, the coordinate position (x'y) of the XY plane is the position in the display screen 3ia (step SB4). : YES) 'When drawing (step SB5: YES), the coordinate position (X, y) of the new XY plane is stored in the internal memory as the current drawing position (step SB9). Then, the control unit 151 performs the following processing. First, the control unit 1 5 checks whether or not the z coordinate is changed (step s B10 ). Then, if the z coordinate is not changed (step SB 1 0: NO), the control unit 151 immediately draws the position (X, y) between the previous drawing position (X, y) and the current drawing position (X, y) in the display screen 31a. The line in which the thickness of the drawing position (X, y) is set to the thickness of the setting is drawn (step SB 1 3 ). On the other hand, the control unit 151 calculates the indication position (instruction sound) by subtracting the new z coordinate from the z coordinate of the z coordinate stored as the reference position when the z coordinate is changed (step SB10: YES). The amount of movement of the reference position of 100 million in the vertical direction in step SB6 (step SB 1 1 ) » that is, the control unit 151 obtains a positive or negative 値 as the amount of movement. Next, the control unit 151 increases or decreases the thickness of the line to be drawn in accordance with the calculated amount of movement (step SB12). In the processing of step SB12, when the calculated movement amount is positive 値 and the indicated position is moved downward from the reference position, the control unit 151 performs a ratio of the line thickness to be drawn to the extent of the movement amount. The reference thickness is also set coarsely. Further, in the processing of step SB12, the control unit 151 performs the line thickness to be drawn in accordance with the amount of movement when the calculated movement amount is negative -45 - 201140394 値 and the indicated position is moved upward from the reference position. The degree is set to be finer than the reference thickness. Then, the control unit 151 draws between the previous drawing position (X, y) and the current drawing position (X, y) in the display screen 31a, and draws the thickness of the current drawing position (X, y) as the setting. Thick lines (step SB13). After that, the control unit 151 temporarily returns to the processing of step SB2, and repeats the processing of steps SB9 to SB13 every time the instruction sound is detected while the indicator sound can be detected. Therefore, as shown in the state I of FIG. 19, After the start point S is displayed on the display screen 31a, for example, when the user presses the push button switch 72 while moving the front end portion of the stylus pen 70 in the obliquely lower right direction, as shown in the state II of Fig. 19, the display is performed. The screen 3 1 a depicts a line K that gradually becomes thicker from the starting point S toward the right. Further, when the user moves the stylus pen 70 in the obliquely upper right direction, as shown in the state III of Fig. 19, the thickness of the line κ in the drawing gradually becomes thinner and extends to the right. That is, the input processing of the line graph information is performed. On the other hand, the control unit 151 does not detect the indication sound during the process of repeating the processing after step SB2 (step SB 2: NO), and the state in which the indication sound cannot be detected continues for a predetermined time or longer, that is, the ratio When the transmission interval of the indication sound in the stylus 7 is longer than the predetermined time (step SB14: YES), the following processing is performed. In other words, the control unit 151 restores the thickness of the line to be drawn to the thickness of the reference -46 to 201140394 (step SB15), and sets the drawing flag to the OFF state (step SB16). The process of setting the flag to the OFF state will depict the process by which the flag is erased by the internal memory. Thereafter, the control unit 151 returns to the process of step SB2, and the process of step S B 2 and subsequent steps is repeatedly executed while the user cancels the brush mode. Therefore, after the user draws the desired line and temporarily stops the operation of pressing the push button switch 72 to stop the occurrence of the instruction sound, the button switch 72 is pressed again, whereby the drawing of the new line can be started. As described above, when the pen input mode is set in the portable information terminal 100 when the pen input function is used, the user can draw a desired line by moving the stylus pen 70 in the vertical and horizontal directions with respect to the display screen 31a. At the same time, the user can move the stylus 70 up and down in the depiction of the line to change the thickness of the line. In other words, the user can draw the line or character of the desired shape on the display screen 3 1 a while adjusting the line thickness freely while using the same feeling as when writing a line or a character with a brush. (Line Graph Mode) Next, the operation of the portable information terminal 100 when the user sets the line graph mode will be described. Fig. 20 is a flowchart showing the processing contents of the control unit 151, and Fig. 2 shows the operation of the stylus pen 70 in the setting of the line graph mode, and the display screen of the LCM 31 in response to the operation of the stylus pen 70. An explanatory diagram of an example of a change in display content in 31a. As shown in Fig. 20, the control unit 151 starts the operation while setting the line graph mode, and first starts the detection of the indication sound by the stylus 70 - 47 - 201140394, and the line to be drawn The thickness is set to a predetermined reference thickness (step SC 1 ). Further, the detection operation of the indicator sound is the same as in the case of the soft key mode and the brush mode, and the control unit 151 starts the instruction sound in each microphone of the complex array microphone described above when the detection operation of the instruction sound starts. The count of elapsed time used in the calculation of the arrival time difference. After the processing of step SC1 is performed, the control unit 151 checks sequentially whether or not the indication sound of the stylus pen 70 can be detected (step SC2). In other words, the control unit 151 sequentially confirms whether or not the sound pressure level of the output signals of the first to fourth microphones 6A to 6D exhibits a peak time with a slight time difference. Next, when the control unit 151 can confirm that the sound pressure level of the output signals of the first to fourth microphones 6A to 6D exhibits a peak time with a slight time difference, it is determined that the indicator sound can be detected at that time point (step SC2: YES). The indicated position information indicating the indicated position belonging to the indication sound transmission position, that is, the coordinate position in the orthogonal coordinates shown in FIG. 12A (X, y, z) is obtained by the processing described in FIG. ) (step SC3). Next, the control unit 151 converts the z coordinate in the obtained coordinate position (x, y, z) into a y coordinate (step SC4), and confirms whether or not the converted coordinate position (x'y) is displayed. The position in the screen 31a (step SC5). If the converted coordinate position (x, y) is not in the display screen 31a (step SC5: NO), the control unit 151 returns to the processing of step SC2 without doing anything. Further, when the coordinate position (X, y) after the conversion is within the display screen 31a (step SC5: YES), the control unit 15 further confirms whether or not it is drawn in the drawing - 48-201140394 (step SC6) » In addition, step SC6 The confirmation is performed by confirming whether or not the internal memory is marked with a flag to be described later. At the beginning of the process start, even if the converted coordinate position (X, y) is within the display screen 31a, it is not in the state of drawing (step SC6: NO). Therefore, the control unit 151 first records the converted coordinate position (X, y) as the drawing position in the internal memory, and additionally sets the drawing flag indicating the drawing (step SC7). In addition, the setting of the depiction flag will depict the processing of the flag in the internal memory. Then, the control unit 151 displays the start point at the drawing position (X, y) in the display screen 31a (step SC8), and temporarily returns to the process of step SC2. In other words, when the user presses the push button switch 72 while the front end portion of the stylus pen 70 is positioned above the desired position of the display screen 31a, as shown in the state I of FIG. 21, on the display screen 31a. The starting point S is displayed. At the same time, the drawing position (X, y) in the display screen 31a is memorized. However, unlike the case of the brush mode described above, since the vertical direction (y-axis direction) of the display screen 31a is the vertical direction (z-axis direction) of the three-dimensional space, for example, the front end portion of the stylus pen 70 abuts When the screen 31a is displayed, the display position of the start point S is a position that is in contact with the lower side of the display screen 31a. Next, the control unit 151 acquires a new coordinate position (X, y, z) every time the instruction sound is detected (step SC2: YES) (step SC3), and obtains the obtained coordinate position (X, y, z). The z coordinate in the middle is converted to the y coordinate (step SC4). Next, if the converted coordinate position (X, y) is the position within the display screen 31a - 49 - 201140394 (step SC5: Yes), and is in the drawing (step SC6: YES), the control unit 151 will new The obtained coordinate position (X, y) after the conversion is stored in the internal memory as the current drawing position (step SC9). Then, the control unit 151 draws a line connecting the previous drawing position (X, y) and the current drawing position (X, y) on the display screen 31a (step SC10). Thereafter, the control unit 151 temporarily returns to the processing of step SC2, and repeats the processing of steps SC4 to SC6, step SC9, and step SC10 every time the instruction sound is detected while the indicator sound is detectable. Therefore, as shown in the state I of Fig. 21, after the display screen 31a displays the start point S, for example, when the user presses the button switch 72 to face the stylus 70 (the front end portion) in a direction away from the display screen 31a When the upper side is moved in a manner of drawing a spiral, the line K can be drawn on the display screen 31a in the order of the state II of the 21st drawing and the state III of the 2nd figure, that is, the input processing of the line drawing information is performed. That is, a line K indicating the trajectory of the front end portion of the stylus pen 70 is drawn on the display screen 31a, and the line K is made to be parallel to the display screen 31a and to the longitudinal direction of the display screen 31a (y-axis direction). In the state in which the observation is performed in unison, that is, in the state of being observed in a specific direction, the control unit 151 is unable to emit an instruction sound during the process of repeating the processing of step SC2 and subsequent steps (step SC2: No), and the state in which the indication sound cannot be detected continues for a predetermined time or longer, that is, when the transmission interval of the indication sound in the stylus pen 70 is continued for a predetermined time or longer (step SC11: YES), the flag will be drawn. Set to the OFF state (step SB16). The process of setting the -50-201140394 flag to the OFF state is a process of erasing the flag from the internal memory. Thereafter, the control unit 151 returns to the processing of step SC2, and repeats the processing of step SC2 and subsequent steps until the user releases the line graph mode. Therefore, after drawing the desired line, the user temporarily stops the operation of pressing the push button switch 72 to stop the transmission of the command sound, and then presses the push button switch 72 again, whereby the drawing of the new line can be started. As described above, when the portable information terminal 100 is set to the cable map mode when the pen input function is used, the user can move the stylus pen 70 on the upper side of the display screen 31a to the front end of the stylus pen 70. The portion corresponds to the movement trajectory of the 3-dimensional space, and a line graph indicating the shape when the movement trajectory is observed from a specific direction can be drawn. In other words, the pointing position detecting device according to the third embodiment includes a display module having a display screen, and a plurality of microphones are disposed apart from each other on an outer peripheral portion of the display screen for detecting a three-dimensional element on the display screen. An indication sound generated by the space; the time difference acquisition unit acquires a time difference of arrival of the instruction sound between the two microphones in combination with the three types of microphones; and the position information acquisition unit is obtained by the time difference acquisition unit For each of the aforementioned arrival time differences, a hyperboloid with the aforementioned microphone corresponding to the arrival time difference is derived as a focal point, and the intersection of the three hyperboloids derived as the position is obtained as the position information for emitting the indication sound. Then, in the portable information terminal 1 including the pointing position detecting device in the third embodiment, when the user inputs the work using the pen-51 - 201140394, the first to fourth microphones are used. 6A to 6D detect the pointing sound emitted by the stylus pen 70, and obtain a coordinate position indicating the position of the front end portion of the stylus pen 70 belonging to the pointing sound transmitting position based on the arrival time difference of the pointing sound between the microphones of the groups. (x, y, z) is used as the indicated position information indicating the pointed position on the display screen 31a. Therefore, as shown in the case where the touch panel of the resistive film type is used to detect the pointed position of the display screen 31a, it is not necessary to cover the display screen 31a with other members. Therefore, the indicated position in the display screen 3 1 a can be detected without degrading the display characteristics of the LCM 1. Further, in the portable information terminal 1A, in order to obtain the position information (X, y, z) of the third dimension as the pointing position information, the soft key 501 displayed on the display screen 31a in the soft key mode described above is available. A plurality of characters and the like are assigned to one of a plurality of operation buttons. In other words, the number of operation buttons displayed on the display screen 31a can be reduced as compared with the case where a normal keyboard is used to input a character or the like by button selection on the screen. Therefore, by making the display surface of the soft key 501 small, the display screen 31a can be effectively used when characters or the like can be input by the pen input function. Further, in the above-described brush mode, as described above, the line thickness in the drawing of the display screen 31a is sequentially changed in response to the up and down movement of the stylus pen 70, thereby allowing the user to write lines or characters with a brush. The same feeling feels free to adjust the line thickness. Further, in the aforementioned line graph mode, as described above, it is possible to correspond to the movement trajectory of the front end portion of the stylus pen 70 in the 3-dimensional space, and it is possible to draw a table-52-201140394 when the movement trajectory is observed from a specific direction. Line drawing of the shape. Further, in the drawing operation of the online image, the user sequentially confirms the line graph (moving trajectory) caused by the viewpoint different from the actual viewpoint, thereby making it easier to display a slightly complicated three-dimensional shape line graph. Depiction. In the implementation of the present invention, the configuration and the like of the portable information terminal 100 described in the present embodiment may be changed as follows. For example, in the first to fourth microphones 6A to 6D, two straight lines LL and MM in which two sets of microphones are orthogonal to each other are disposed, and the two straight lines LL and MM may not exist in the same plane. Different planes parallel to each other. Further, the two straight lines LL, MM may also exist in different planes that are not parallel to each other. Further, as shown in the present embodiment, when the two straight lines LL and MM are orthogonal to each other, it is convenient to calculate the coordinate position (x, y, z) of the arbitrary indication position P on the display screen 31a, but 2 The straight lines LL, MM may also form only intersections in the display screen 31a at least when projected on the display screen 31a. Further, the first to fourth microphones 6A to 6D may be arranged at respective corners of the display screen 31a as shown in FIG. In other words, the first to fourth microphones 6A to 6D may be arranged in pairs on a straight line L1 including a diagonal line of the display screen 31a and a line M1 including another diagonal line. Further, the first to fourth microphones 6A to 6D in the LCM 1 are provided so that the pointing sound emitted from the stylus pen 70 can be detected on the display screen 31a when the user instructs the display screen 31a to an arbitrary position. -53- 201140394 Yes, subject to change. In other words, the first to fourth microphones 6A to 6D can be disposed at any position on the outer peripheral portion of the display screen 31a as long as they are separated from each other. Further, in the present embodiment, the first to fourth microphones 6A to 6D are provided on the outer peripheral portion of the display screen 31a, and one of the three sets of microphones is set to one side of each of the other two sets of microphones. microphone. That is, the first and fourth microphones 6A, 6D are handled as a set of microphones. However, for example, in addition to the first to fourth microphones 6A to 6D, the fifth microphone and the sixth microphone may be separately provided on the outer peripheral portion of the display screen 31a, thereby forming two microphones that do not constitute the microphones of the other groups. A microphone of each of the three sets of microphones. Further, for example, in addition to the first to fourth microphones 6A to 6D, the fifth microphone may be provided on the outer peripheral portion of the display screen 31a, whereby only one of the five microphones may be configured as two sets of microphones different from each other. To handle. Further, only the first to third microphones 6A to 6C may be provided on the outer peripheral portion of the display screen 31a, and each of the three microphones may be configured to form one of the different sets of microphones and the other group. In other words, the first and second microphones 6A and 6B can be regarded as the first group, and the second and third microphones 6B and 6C can be set as the second group, and the third and first microphones can be used. . 6. . C. . 6A is regarded as the third group and is treated separately. Further, as shown in the present embodiment, the case where the four microphones of the first to fourth microphones 6A to 6D are provided on the outer peripheral portion of the display screen 31a is not required to be -54-201140394, even if it is on the outer periphery of the display screen 31a as described above. The case where five microphones or six microphones are provided in the section 'may be used in any combination for each combination of microphones. Further, even when three microphones, five microphones, or six microphones are provided on the outer peripheral portion of the display screen 31a, the specific arrangement of the respective microphones in the outer peripheral portion may be in any arrangement. In addition, the control unit 155 can add the function of the position acquisition control unit and the correction unit of the present invention, and when the instruction sound is detected, the following processing different from the present embodiment can be used to obtain the display of the display pair. The coordinate position (X, y, z) of any position P of the screen 31a is indicated. For example, the control unit 151 performs the coordinate position (X, y, z) of the intersection point P of the three different hyperboloids shown in FIG. 13B in the order described in the embodiment, and obtains the calculation result as the first. Indicates the processing of location information. Next, the control unit 151 changes the third hyperboloids (hyperbolic) 30p and 30q having the first and fourth microphones 6A and 6D as the focus among the three hyperboloids, as shown in FIG. After the third microphones 6B and 6C are used as the hyperboloids 40p and 40q of the focus, the coordinates (X, y, z) ° of the intersection point P of the three different hyperboloids are calculated according to the same principle as the present embodiment. The control unit 151 performs the arrival time difference of the indicator sounds in each of the three sets of microphones formed by the other combination (the second combination) different from the combination (the first combination) in the present embodiment, according to The obtained arrival time difference of each group is calculated, and the coordinate position -55 - 201140394 (x'y, z) of the intersection point P of the three hyperboloids is calculated, and the calculation result is obtained as the processing of the second indication position information. Further, Fig. 23 is the same as Fig. 13B, and the shape or positional relationship is practically different only for the convenience of displaying each hyperbolic surface (hyperbolic). Then, the control unit 151 calculates the X coordinate of the point located between the X coordinate in the first indicated position information and the x coordinate in the second indicated position information as the corrected X coordinate. Similarly, the control unit 151 calculates the y coordinate of the point between the y coordinate in the first indicated position information and the y coordinate in the second indicated position information, and obtains the calculation result as the corrected y coordinate. Further, the control unit 51 calculates the z coordinate of the point located between the Z coordinate in the second indication position information and the Z coordinate in the second indication position information, and obtains the calculation result as the corrected z coordinate. In other words, the control unit 151 corrects the first indication position information by the second indication position information, and obtains the coordinate position (X, y, Z) formed by the coordinates of the corrected X, y, and Z. 3 indicates the location information, and obtains the third indication location information as the final indication location information. As described above, when the combination of the microphones of the three sets of microphones is changed, the first indication position information and the second indication position information are obtained, and the obtained i-th indication position information is corrected by the second indication position information, thereby obtaining Finally, the position information (3rd position information) is indicated, and the display screen 3 1 a. " The detection accuracy of the indicated position. Further, unlike the above example, the combination of all the combined microphones of the three sets of microphones may be changed when the first indication position information and the second indication position information are acquired. Further, in the present embodiment, when the position information of the finger-56-201140394 is obtained by the control unit 151, the coordinate 値(x, y, z) of the equation (12) is sequentially substituted to indicate a certain above the display screen 31a. The coordinate 値 of each point in the three-dimensional space in the range is obtained, and the calculation result (η) is obtained, and the coordinate 値(X, y, ζ) obtained when the calculation result (η) is the smallest is described as the configuration of the position information. However, a specific method can be applied to the specific method of obtaining the position information (X, y, ζ) indicating the position information, that is, the intersection of the three hyperboloids (or the point at which the intersection can be determined). On the other hand, the command sounds detected by the first to fourth microphones 6A to 6D may have characteristics in the frequency band of the audible range, or may have characteristics in the frequency band of the non-audible range. When the indicator sound is made to have a characteristic in the frequency band of the audible range, the user can be provided with a reliable operational feeling in the operation of the stylus pen 70. In addition, when the indicator sound is made to have a characteristic in the frequency band of the non-audible range, the user who is annoyed by the audible indication sound can provide a good operating environment, and the surrounding person can feel that the indication sound is noise. The bad situation disappeared. Further, in the portable information terminal 100, in the detection mode of the indicator sound, the first detection mode in which the indicator sound to be detected has a characteristic in the frequency band of the audible range, and the indication sound to be detected are in the non-detection mode. The frequency band of the audible range has two detection modes, such as the second detection mode of the characteristic, and can also ensure that the user can view it as needed. . The configuration of the detection mode of the indication sound is switched. When the portable information terminal 100 secures the above configuration, the user can selectively use the indicator sound having the characteristic in the frequency band of the audible range and the frequency band emitted in the non-audible range according to the preference or the use environment. -57- 201140394 A characteristic indicator sound is used as a stylus. In the present embodiment, when the soft key mode is set as the operation mode when the pen input function is used, the control unit 151 causes the display screen 31a of the LCM 31 to display the soft key 501 composed of a plurality of operation buttons. . However, in the soft key mode, if a plurality of stages of operation positions are imaginarily provided, the control unit 151 may be configured such that a single operation button is not displayed on the display screen 31a. Further, in the present embodiment, an image in which a plurality of operation buttons are assigned with an English letter or a symbol is displayed as an example of the soft key 501. However, the soft key 501 can also be formed, for example, by dividing the number into a plurality of groups as assigners at the respective operation buttons. Further, the control unit 151 may display other information than the text information on the soft key 501 or the single operation button displayed on the display screen 31a of the LCM 31 as long as the information is allocated in advance in accordance with the operation position of each stage. Further, in the present embodiment, when the line graph mode is set as the operation mode when the pen input function can be used, the control unit 151 sets the line graph displayed on the display screen 31a of the LCM 31 to indicate the line of sight and the display screen. 31a is parallel and is in front of the stylus 70 in a state where it is observed in the longitudinal direction (y-axis direction) of the display screen 31a. The line K of the trajectory. However, in the line graph mode, the control unit 51 may be configured such that the line graph displayed on the display screen 31a of the LCM 31 is, for example, a state in which the movement range of the end portion before the trajectory of the tip end portion of the stylus pen 70 is observed obliquely upward. -58- 201140394 In addition to jfct, the control unit 151 may also make the line graph of the display screen 31a not displayed in the LCM 31 non-single-. In other words, for example, in the display screen 31a of the LCM 31, the line graph in the state of the x-axis force@gastric stomach to the trajectory is displayed at the same time as the trajectory of the front end portion of the stylus pen 70 is observed from the y-axis direction. Three kinds of line graphs, such as a line graph and a line graph in a state in which the trajectory of the tip end portion of the stylus pen 70 is observed in the z-axis direction. In addition, in the present embodiment, the soft key mode and the brush are prepared in advance. The three types of operation modes, such as the mode and the line graph mode, are described as one for the case where the portable information terminal 1 uses the operation mode of the pen input function. However, in the portable information terminal 100, other operation modes may be set in addition to the three types of operation modes. In the other operation mode, for example, the control unit 151 controls the other image or the like different from the soft key 501 displayed on the display screen 31a in response to the instruction position (instruction position information) of the display screen 31a. The mode or the control unit 151 causes an operation mode in which the display unit 31a re-displays any other information (image information or text information) different from the line drawing in response to the instruction position (instruction position information) of the display screen 31a. Further, in the other operation modes described above, the control unit 151 may be controlled to be displayed on the display screen 3 while the position information is continuously acquired at a predetermined time interval in response to the transmission cycle of the instruction sound in the stylus pen 70. The process of displaying an image or the like in the display or displaying the arbitrary information on the display screen 31a may be performed at any time when the position information is instructed. Further, in the present embodiment, the configuration of the position detecting device of the present invention as the -59-201140394 and the configuration of the display device of the present invention are provided, and the stylus 70 can be used for text or line drawing. The portable information terminal 100 of the input pen input function will be described. However, the pointing position detecting device and the display device of the present invention may be incorporated in other devices, and are not limited to the portable information terminal 100. Further, of course, the coordinate position (X, y, z) indicating the position of the indication detected in the present invention, that is, the position of the indication sound in the three-dimensional space is not limited to the LCM3 1 described in the present embodiment. The pointed position of the display screen may be any indicated position on the display screen of another display device such as a CRT other than the LCM1. Other advantages and modifications will be apparent to those skilled in the art, and the scope of the present invention is not limited to the specific details and representative embodiments shown herein. Therefore, various modifications may be made without departing from the spirit and scope of the general inventive concept as defined by the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing the configuration of an instruction position detecting device according to a first embodiment. Fig. 2A is a layout view of each microphone in the first embodiment. Fig. 2B is a layout view of each microphone in the first embodiment. Third. The figure shows the coordinate position map of each microphone in the first embodiment. Fig. 4A is an explanatory view showing a method of acquiring the indicated position in the first embodiment. -60- 201140394 Fig. 4B is an explanatory view showing a method of obtaining the indicated position in the third embodiment. Fig. 5 is a layout view showing another example of arrangement of the microphones in the first embodiment. Fig. 6 is an explanatory view showing another combination of microphones which is one of the calculation targets of the hyperbola. Fig. 7 is a view showing the configuration of the pointing position detecting device of the second embodiment. Fig. 8A is an explanatory view showing an example of a specific structure of a polarizing plate. Fig. 8B is an explanatory view showing an example of a specific structure of a polarizing plate. Fig. 8C is an explanatory view showing an example of a specific structure of a polarizing plate. Fig. 9 is a view showing the configuration of a portable information terminal of the third embodiment. Fig. 10 is a cross-sectional view showing the schematic structure of the display unit in the third embodiment. Fig. 11 is a schematic block diagram showing the electrical configuration of the portable information terminal in the third embodiment. The 1 2 A map shows the position map of any indicated position in the 3 dimensional space. 1 2B,. The figure shows the coordinate position map of the XY coordinate system of each microphone in the third embodiment. Fig. 13A is a view showing a method of obtaining the position information in the third embodiment. -61 - 201140394 Fig. 1 3B shows an explanatory diagram of a method of obtaining the position information in the third embodiment. Fig. 14 is a flow chart showing the processing contents in the soft key mode. Fig. 15 is a flow chart showing the process of instructing the position information acquisition. Fig. 16 is an explanatory diagram illustrating the operation of the portable information terminal in the soft key mode. Fig. 17A is an explanatory diagram showing the details of the soft keys. Fig. 17B is an explanatory diagram showing the details of the soft keys. Fig. 18 is a flow chart showing the processing contents in the brush mode. Fig. 19 is an explanatory diagram showing the operation of the portable information terminal in the brush mode. Figure 20 is a flow chart showing the processing contents in the line graph mode. Fig. 21 is an explanatory diagram showing the operation of the portable information terminal in the line graph mode. Fig. 22 is a view showing the arrangement of another arrangement example of the microphone in the third embodiment. Figure 23 is an explanatory diagram showing other combinations of three sets of microphones. [Main component symbol description]

1 LCM la Display screen 2A, 2B, 2C, 2D Microphone 3 Amplifier 4 A/D converter-62- 201140394 5 Position acquisition unit 5 a Time difference acquisition unit 5b Position information acquisition unit 6 A to 6 D Microphones 10s, 10t, 20s 20t hyperbola 10p, 10q, 20p, 20q, 30p, 30q hyperboloid (hyperbolic) 11' 12 glass substrate 13 liquid crystal 14, 15 polarizing plate 14a PVA film 14b TAC film 14c phase difference plate 1 4 e transparent adhesive 16 Pixel electrode 1 7 TFT 18 color filter 19 common electrode 20 frame cover 20a display window 30 stylus 3 1 LCM 3 1a display screen 32, 33 glass substrate -63- 201140394 34 liquid crystal 35, 36 polarizing plate 37 light guide plate 38 light Reflective sheet 39 pixel electrode 40 TFT 41 color filter 4 2 common electrode 43 frame cover 43a display window 5 1 LCM 52 liquid crystal panel 53 brightness enhancement film 60 protective cover 60a peripheral portion 70 stylus 7 1 body 72 push button switch 100 portable Information terminal 102 body 103 display unit 104 power button 1 0 5 a ~ 1 0 5 e operation button -64- 201140394 151 Control unit 151a Time difference acquisition unit 151b Position information acquisition unit 151c Display control unit 1 5 1 d 0 Input processing unit 152 ROM 153. Flash memory 154 Key input unit 155 Drive circuit 156 Signal processing unit 157 Amplifier 5 01a Operation button P indicates the position -65-

Claims (1)

201140394 VII. Patent application scope: 1. An indication position detecting device, comprising: a display module having a display screen; a plurality of microphones disposed apart from each other at an outer peripheral portion of the display screen to detect contact with the display screen a time difference obtaining unit that obtains an arrival time difference of the contact sound between two microphones of each of the two combinations of the plurality of microphones, and a position information acquisition unit that derives and acquires the time difference obtained by the time difference acquisition unit The two hyperbolic curves corresponding to the arrival time difference, and the respective hyperbola are hyperbola of the focus of the two microphones in each of the foregoing two combinations of the plurality of microphones, and the two hyperbolic curves derived are obtained. The intersection point serves as positional information for generating the aforementioned contact sound. 2. The instruction position detecting device according to the first aspect of the invention, wherein the time difference acquisition unit acquires a difference in arrival time of the contact sound between the first microphone and the third microphone as a first arrival time difference, and acquires the second microphone and The difference in arrival time of the contact sound between the fourth microphones is a second arrival time difference, and the position information acquisition unit derives a first hyperbola having the first microphone and the third microphone as a focus based on the first arrival time difference, and A second hyperbola in which the second microphone and the fourth microphone are the focus is derived from the second arrival time difference, and an intersection of the first hyperbola and the second hyperbola is obtained as position information for generating the contact sound. -66 - 201140394 3 - The indication position detecting device according to the second aspect of the patent application, wherein the display screen is formed in a rectangular shape, and the first microphone is disposed such that the display screen is located between the first microphone and the first wind The second microphone and the fourth microphone are arranged such that the display screen is located between the second microphone and the first wind, and the indication position detecting device of the third aspect of the patent application is provided. The first microphone, the second microphone, and the third microphone and the fourth microphone are arranged side by side different from the display screen. 5. The pointing position detecting device according to claim 3, wherein the first microphone, the second microphone, the third microphone, and the fourth microphone are disposed at different angles from each other on the display screen. 6. The pointing position detecting device according to the first aspect of the invention, wherein the time difference obtaining unit acquires a difference in arrival time of a contact sound between the first microphone and the second microphone as a first time difference of arrival, and the first microphone and the third microphone are described. The difference between the contact sounds is the second arrival time difference, and the position information acquisition unit is based on the first arrival time and the first microphone and the second microphone as the focus, and the second arrival is based on the second arrival time. The time difference is derived from the second hyperbola in which the aforementioned wind and the third microphone are the focal points, and the aforementioned 3 MacArt style, 4 MacArt style. In the above-mentioned and the aforementioned correspondence, the aforementioned pre-acquisition time difference is derived from the first double first wheat acquisition-67-201140394 before the intersection of the first hyperbola and the second hyperbola as the occurrence of the contact The location information of the sound. 7. An indication position detecting device comprising: a display module having a display screen; a plurality of microphones disposed apart from each other on an outer peripheral portion of the display screen, and detecting a three-dimensional space from the display screen a time difference acquisition unit that acquires an arrival time difference of the indicator sound between two microphones of each of the three combinations of the plurality of microphones and the wind; and a position information acquisition unit that derives and obtains the time difference acquisition unit And obtaining the hyperboloids corresponding to the difference in the arrival time difference, and the two hyperbolas each of the three combinations of the plurality of microphones have a hyperboloid of a focus, and the three exported are obtained. The intersection of the hyperbola serves as the positional information for emitting the aforementioned indication sound. 8. The instruction position detecting device according to claim 7, wherein the time difference acquisition unit acquires a difference in arrival time of the instruction sound between the first microphone and the third microphone as a first arrival time difference, and acquires the second microphone and the 4, the arrival time difference of the indication sound between the microphones is the second arrival time difference 'and the target between the first microphone and the fourth microphone is acquired", and the difference in arrival time of the voice is referred to as the third arrival time difference, and the position of the BU is described. The information acquisition unit derives a second --68-201140394 curved surface having the first microphone and the third microphone as a focus based on the first arrival time difference, and derives the second microphone and the fourth microphone based on the second arrival time difference. The second hyperboloid as a focus is obtained by deriving a third hyperboloid having the first microphone and the fourth microphone as a focus based on the third arrival time difference, and acquiring the first hyperboloid, the second hyperboloid, and the third double The intersection of the curved surfaces serves as the positional information for the aforementioned indication sound. 9. The pointing position detecting device according to claim 8, wherein the display screen is formed in a rectangular shape, and the first microphone and the first microphone are disposed such that the display screen is located between the first microphone and the third microphone. In the third microphone, the second microphone and the fourth microphone are disposed such that the display screen is positioned between the second microphone and the fourth microphone. 1. The instruction position detecting device according to claim 9, wherein the first microphone, the second microphone, the third microphone, and the fourth microphone are associated with sides different from each other on the display screen. Mode configuration. 11. The instruction position detecting device according to claim 9, wherein the first microphone, the second microphone, the third microphone, and the fourth microphone are arranged to correspond to different corners of the display screen. . 1 2. An indication position detecting method, comprising: a time difference obtaining step of acquiring two combinations of two types of microphones of a plurality of microphones that are disposed apart from each other on an outer peripheral portion of the display screen - 69- 201140394 a difference in arrival time of the contact sound between the microphones to detect a contact sound with respect to the display screen in the display module; and a position information obtaining step of deriving two of the aforementioned arrival time differences obtained in the time difference obtaining step a hyperbola, wherein each of the two microphones in each of the foregoing two combinations of the plurality of microphones has a hyperbola of focus, and the intersection of the two hyperbola derived is obtained as the contact sound. Location information. The method of detecting an indication position according to claim 12, wherein the time difference acquisition step acquires a difference in arrival time of the contact sound between the first microphone and the third microphone as a first arrival time difference, and obtains a second time difference The difference in arrival time of the contact sound between the microphone and the fourth microphone is the second arrival time difference, and the position information acquisition step is based on the first arrival time difference to derive the first focus of the first microphone and the third microphone. The hyperbola' derives a second hyperbola having the second microphone and the fourth microphone as a focus based on the second arrival time difference, and obtains an intersection of the first hyperbola and the second hyperbola as a position at which the contact sound is generated. News. 1 4 . An indication position detecting method, comprising: a time difference obtaining step of acquiring between two microphones of each of a combination of four types of microphones of four microphones disposed on an outer peripheral portion of the display screen a difference in arrival time of the contact sound to detect a contact sound for the display screen in the display module; and -70-201140394 position information obtaining step 'which derives a hyperbola corresponding to the aforementioned arrival time difference obtained in the aforementioned time difference obtaining step And each of the two hyperbolas in the above four combinations of the plurality of microphones has a hyperbola of a focus, and position information for generating the contact sound is obtained based on the derived hyperbola. 15. The method according to claim 14, wherein the time difference obtaining step includes: a first time difference obtaining step of obtaining a difference in arrival time of the contact sound between the first microphone and the third microphone as the first a second time difference obtaining step of obtaining a difference in arrival time of the contact sound between the second microphone and the fourth microphone as a second arrival time difference, and a third time difference obtaining step of acquiring the first microphone and the fourth microphone The difference in arrival time I between the contact sounds is the third arrival time difference, and the fourth time difference obtaining step is to obtain the difference in arrival time of the contact sound between the second microphone and the third microphone as the fourth arrival time difference. 1. The method according to claim 15, wherein the position information obtaining step includes: a first position information obtaining step of deriving the first microphone and the first according to the first time difference of arrival 3 - the first double curve, and the first to second microphones and the fourth microphone are used as the focus to derive the first hyperbola and the second double position; the second position information acquisition step, Deriving the first microphone and the third hyperbola based on the root difference, and deriving the third hyperbola and the fourth double position based on the fourth to second microphones and the third microphone; and correcting the step The first intermediate position is a bit 17-type indicating position detecting method for generating the contact sound, and includes: a time difference obtaining step of acquiring two microphones of three types of a plurality of microphones on the outer peripheral portion of the face-to-face The above-mentioned instruction sound is measured from the display screen in the display module, and the location information acquisition step is derived and exported. The hyperbola corresponding to the aforementioned arrival time difference is the intersection of the two hyperboloids of the two microphones having the focus of the plurality of microphones, and the second hyperbola of the focus is derived as the aforementioned time difference, and the curve is obtained. The intersection point is derived from the fourth hyperbola of the focus based on the time difference of the microphone as the focus of the third arrival time 4, and the intersection of the curve is used as the information of the second position and the second position. Arranging the time difference of each group in the combination of the display microphones, and obtaining the three hyperboloids in the time difference by the finger emitted by the inspection dimension space, and obtaining the curved surface of each of the three combinations The position information of the indicator sound. The method of detecting an indicated position according to claim 17, wherein the time difference obtaining step obtains a difference in arrival time of the indication sound between the first microphone and the third microphone as the first arrival time: The difference in arrival time of the indication sound between the microphone and the fourth (fourth) wind is the second time difference, and the difference in arrival time of the indication sound between the microphone and the fourth microphone is obtained as the third arrival time difference; BIJ describes the position information. In the acquisition step, the first hyperboloid having the first microphone and the third microphone as a focus is derived based on the first arrival time difference, and the second microphone and the fourth microphone are used as the second focus based on the second arrival time difference. The hyperboloid derives a third hyperboloid having the second microphone and the fourth microphone as a focus based on the third arrival time difference, and obtains an intersection of the first hyperboloid and the second hyperboloid and the third hyperboloid as an emission The position information of the aforementioned indicator sound. 19. An indication position detecting method, comprising: a time difference obtaining step of: obtaining the indication sound between two microphones of each combination of four types of microphones of four microphones disposed apart from each other on an outer peripheral portion of the display screen The arrival time difference, in order to detect the indication from the three-dimensional space on the display screen in the display module. 3ίζ: · Ί3, 曰, and location information acquisition steps, which are derived and in the aforementioned time difference acquisition step Obtaining a hyperboloid corresponding to the foregoing arrival time difference, and the respective two-73-201140394 curved surface is a hyperboloid of the focus of the two microphones in each of the foregoing four combinations of the plurality of microphones, according to the derived double The surface acquires position information that gives the aforementioned indication sound. 20. The method according to claim 19, wherein the time difference obtaining step includes: a first time difference obtaining step of obtaining a difference in arrival time of the indicator sound between the first microphone and the third microphone as the first The second time difference acquisition step acquires the arrival time difference of the instruction sound between the second microphone and the fourth microphone as the second arrival time difference, and the third time difference acquisition step acquires the first microphone and the fourth microphone. The arrival time difference between the instruction sounds is the third arrival time difference; and the fourth time difference acquisition step acquires the arrival time difference of the instruction sound between the second microphone and the third microphone as the fourth arrival time difference. 21. The method according to claim 21, wherein the position information obtaining step includes: a first hyperboloid deriving step of deriving the first microphone and the third microphone as a focus based on the first arrival time difference a first hyperboloid; a second hyperboloid derivation step, according to the second arrival time difference guide -74-201140394, the second hyperboloid with the second microphone and the fourth microphone as the focus; the third hyperboloid exporting step 'Deriving a third hyperboloid with the first microphone and the fourth microphone as a focus based on the third arrival time difference; the fourth hyperboloid deriving step deriving the second microphone and the aforementioned based on the fourth arrival time difference a fourth hyperboloid having a third microphone as a focus; a first position information obtaining step of deriving the intersection of the second hyperboloid and the second hyperboloid and the third hyperboloid as a first position; and a second position information obtaining step Deriving the intersection of the first hyperboloid and the second hyperboloid and the fourth hyperboloid as a second position; and correcting the step Between the first position and the second position as a position indicating the emitted sound location. -75-