JP4065958B2 - Search object detection method and search object detection system - Google Patents

Description

  The present invention relates to a search object detection method and a search object detection system capable of easily detecting a search object by receiving light emitted from an illumination apparatus with an electronic tag and receiving sound waves generated from the electronic tag with an illumination apparatus.

  In recent years, RFID tags using RFID (Radio frequency identification) technology have been spreading widely, such as commuter pass recognition for transportation using non-contact IC cards, article management systems that attach electronic tags to articles and grasp their positions, etc. Is also possible.

On the other hand, as a technique for detecting a search object, as in Patent Document 1, an electronic tag attached to a search object in advance receives a radio wave from a transmission device and emits sound and light. In addition, as in Patent Document 2, an electronic tag that is transmitted in response to a specific frequency radio wave is attached to an article (search item) in a room such as a house, and the article is associated with the room and stored in a detector. is there. Furthermore, for crime prevention use, as disclosed in Patent Document 3, a device that detects a moving body with a non-contact sensor and irradiates the moving body with a spotlight is disclosed. When searching for a mobile phone, it is common practice to call the mobile phone and recognize the location of the mobile phone from the ringtone.
Japanese Patent Laid-Open No. 11-31680 JP 2004-69331 A JP 2002-83383 A

  By the way, when searching for items, the item to be searched is not always placed on a desk or the like, but may be in a place where the item is hidden under a newspaper or a magazine. However, in Patent Documents 1 to 3, when the search object is in a place hidden under a newspaper or a magazine, the weak light emitted by the electronic tag cannot find the light from the surroundings, and only the sound is heard. Had the problem of having to look into. The sound alone is the same as calling the mobile phone above and searching for the mobile phone, but just because the sound is heard, even if the approximate location of the search can be recognized, the search can be identified. is not. Further, when the user is a hearing-impaired person or an elderly person, it may be difficult to find a search object. Even when the mobile phone is in the manner mode, it is impossible to specify (narrow down) the search object (mobile phone).

  In addition, the system in which the electronic tag described in Patent Document 2 emits a solid identification radio wave has a problem in that the position detection accuracy of the electronic tag is difficult due to the nature of the radio wave, and the accurate position cannot be specified. That is, even if the approximate location of the search item can be recognized, it is not highly accurate until the search item is specified (narrowed down).

  Furthermore, in the apparatus that detects the moving body by the non-contact sensor described in Patent Document 3 and irradiates the spot with the spotlight, the non-contact sensor and the apparatus that irradiates the spotlight are independent. The accuracy of irradiating the spotlight is uniquely determined by the detection accuracy of the non-contact sensor, and there is a problem that an error occurs in detection of the non-contact sensor.

  The electronic tag must be small enough to be attached to an article. As a result, the battery that can be mounted on the electronic tag is small, but as a means for generating light with a small battery, the power consumption is low. There was no choice but to use light emitting diodes that could not emit strong light.

  Therefore, an object of the present invention is to provide a search object detection method and a search object detection system capable of specifying a search object even if the search object is placed in a place hidden under a newspaper or a magazine. To do.

A search object detection method according to the present invention that achieves the above-described object includes an electronic tag attached to a search object, a transmission device that transmits a transmission wave to the electronic tag, and an illumination device that includes a spotlight that emits light. If the originating device transmits a transmission wave to the electronic tag, the electronic tag emits sound waves received the transmitted wave, the lighting device is configured to receive the sound waves which the electronic tag is emitted by the microphone, the microphone receives A spot detection method in which a spotlight emits light in a sound source direction of a sound wave, wherein the electronic tag includes a photosensor that receives light from the spotlight, and the spot received by the photosensor According to the light from the light, the frequency of the generated sound wave, the sound pressure, or the period of the sound is appropriately changed, the lighting device Ikurofon in accordance with a change in the sound wave of the electronic tag receives the light diameter of irradiating the spot light, light intensity, or, and changing the frequency of light appropriate. On the other hand, a search object detection system according to the present invention includes an electronic tag attached to a search object, a transmission device that transmits a transmission wave to the electronic tag, and an illumination device that has a spotlight that irradiates light. A receiving circuit that receives a transmission wave from the transmitting device, and a sound wave generator that generates a sound wave, and the illumination device includes an irradiation position variable unit that changes an irradiation position of the spotlight, and the electronic tag And a sound source estimation circuit for estimating a distance to the sound source and a direction of the sound source, wherein the electronic tag receives light from the spotlight. And a control circuit for controlling the sound wave generator from the output signal of the light sensor, and according to the light of the spotlight, Wave number, sound pressure, or period of sound is changed as appropriate, and the illumination device includes a sound wave analysis circuit that analyzes a change in sound waves from the sound wave generator, and an output signal of the sound wave analysis circuit that generates the spotlight. A control circuit for controlling the light, and appropriately changing the diameter, intensity, or frequency of light emitted from the spotlight according to a change in sound waves generated from the electronic tag. And Here, as the transmitting device, a wireless remote controller, a mobile phone, a personal digital assistant (PDA), or the like is applicable.

  When a person (user) who detects a search object transmits a transmission wave to the electronic tag by the transmission device, the electronic tag emits a sound wave, and when the microphone of the illumination device receives the sound wave, the sound source estimation circuit enters the microphone. Then, the position of the sound source is estimated, and the spotlight is directed in the direction of the sound source estimated by the irradiation position variable means of the illumination device. The target object can be detected by irradiating the spotlight. Even if a search object is in a place where it cannot be directly seen, such as under a newspaper or a magazine, the search object can be found by removing the newspaper or magazine in order to irradiate the top of the newspaper or magazine.

  As a search object detection method and a search object detection system according to the present invention, a lighting device is a means for receiving sound waves generated from an electronic tag, and a sound source estimation circuit for estimating a distance to a sound source and a direction of the sound source as means for receiving sound waves generated from an electronic tag The structure provided with is preferable. Since the position of the sound source can be estimated from the difference between the output signals from at least two microphones provided in the illumination device, the circuit configuration is facilitated.

As the search object detection method and the search object detection system according to the present invention, the electronic tag appropriately changes the frequency, sound pressure, or sound cycle of the generated sound wave in accordance with the light of the spotlight. A feature is that a means for appropriately changing the diameter of the spotlight, the intensity of the light, or the frequency of the light according to the change of the sound wave generated from the tag is provided.

  In other words, if the nature of the sound wave generated from the electronic tag is monotonous with respect to the light received by the electronic tag, even if the error occurs in the location of the sound source and the spotlight is applied, Even if it doesn't exist, the user can't know it and can't find what he's looking for. However, in consideration of errors that occur when specifying the sound source position, the diameter of the spotlight becomes larger than necessary, and it is not easy to find a search object from the irradiated area. Here, the error that occurs when the sound source position is specified includes, for example, a measurement error due to the illuminating device receiving the sound wave after the sound wave emitted from the electronic tag is reflected on the indoor article. The same applies to the case where the light property of the spotlight of the illumination device is monotonous with respect to the sound wave received by the illumination device.

  On the other hand, according to the present invention, the property of the sound wave generated from the electronic tag is appropriately changed according to the light of the spotlight, and the property of the light of the spotlight (light diameter, If the intensity of light or the frequency of light is appropriately changed, the causal relationship between the sound wave and the light can be easily grasped. For example, a control circuit that takes in an output signal of an optical sensor of an electronic tag that receives spotlight light controls a sound wave generator, and the above optical sensor receives from a microphone of an illumination device that receives a sound wave generated from the electronic tag. The control circuit that takes in the output signal of the sound wave analysis circuit that estimates the reflected light controls the spotlight, so that the diameter of the spotlight's light is increased so that it falls on a search object with an electronic tag, or the diameter is narrowed down. Then, the search item can be narrowed down (specified).

  Further, as the search object detection method and the search object detection system according to the present invention, the detection result of the detection means at the time of starting the search of the search object is stored as an initial value, and thereafter, based on the difference between the detection result of the detection means and the initial value. A method of obtaining the position of the search object is preferable. The initial values of the detection results of these detection means are stored in the control circuit, and thereafter the location of the search object can be specified by obtaining the position of the search object based on the difference between the detection result of the detection means and the initial value. Here, the detection means is a microphone of an illumination device that receives sound waves generated from the electronic tag, and an optical sensor of the electronic tag that receives light from a spotlight of the illumination device. In addition, the initial value is the output signal of the optical sensor of the electronic tag at the time of starting the search for the search object, and the above-mentioned from the microphone of the illumination device that receives the sound wave generated from the electronic tag at the time of starting the detection of the search object. It is the output signal of the sound wave analysis circuit which estimates the light which the optical sensor received.

  Further, as the search object detection method and the search object detection system according to the present invention, the illumination device is initially set to have a predetermined diameter of light emitted from the spotlight, and a change in sound wave generated from the electronic tag. If there is no change, the diameter of the light emitted from the spotlight is made larger than the above-mentioned predetermined diameter. Thus, a method of obtaining the position of the search object is preferable.

  That is, in the initial state, the illumination device sets the diameter of light emitted from the spotlight to a predetermined size. When this light cannot irradiate the electronic tag and the sound wave generated from the electronic tag does not change, the irradiation diameter is made larger than the predetermined diameter. When the electronic tag is irradiated with the light of the spotlight and the sound wave generated from the electronic tag changes, the diameter of the spotlight is reduced to narrow down the direction of the electronic tag. With this reduction, when the electronic tag is removed from the diameter of the spotlight and the sound wave generated from the electronic tag changes, the irradiation direction of the light from the spotlight is moved back and forth and right and left. In this way, when the spotlight is not irradiating the electronic tag, the spotlight diameter is increased to search for the electronic tag, and when the spotlight is irradiating the electronic tag, the spotlight diameter is decreased. To narrow down. When the electronic tag is removed from the spotlight during narrowing down, the spotlight is corrected to irradiate the electronic tag by moving the spotlight back and forth, left and right, more accurately irradiating the electronic tag with the light of the spotlight, and the position of the search object Identify.

  Here, the diameter of the light emitted from the spotlight of the lighting device in the above-described initial state is a size that takes into account an error that occurs when the sound source position is specified, and is large enough to irradiate the electronic tag with the first irradiation. Set in advance. This is effective for shortening the time for narrowing the sound source position.

  In addition, when the sound wave generated by the electronic tag is an audio frequency that can be heard by a person, the search object can be detected by sound in addition to the light emitted by the spotlight.

  ADVANTAGE OF THE INVENTION According to this invention, it can identify and detect a search thing intuitively by receiving the sound wave which emits from an electronic tag, and applying the light of a spotlight to an electronic tag from an illuminating device. In addition, even if the search object is in a place where it cannot be seen directly, such as under newspapers or magazines, the light of the spotlight irradiates the newspapers or magazines based on the sound waves generated by the electronic tag. It is possible to easily detect a search object by the light to be detected. Then, the control circuit controls the sound wave generator from the output signal of the optical sensor of the electronic tag that receives the light of the spotlight, so that the diameter of the light of the spotlight is increased so as to be applied to the search object with the electronic tag. By narrowing down the diameter, the search object can be narrowed down (specified), and the search object can be detected more quickly and accurately more intuitively.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 shows an embodiment of a search object detection system. FIG. 1 shows a transmitting device 10 possessed by a user, an electronic tag 20 that operates by receiving sound waves or radio waves from the transmitting device 10, and irradiates a spotlight 33 according to changes in sound waves generated from the electronic tag 20. It is comprised from the illuminating device 30 which adjusts a position and the diameter of light.

  As shown in FIG. 1, the transmission device 10 includes a button 11 corresponding to the electronic tag 20 attached to the search object and a transmission circuit 12 that transmits an individual identification signal to the electronic tag 20 using sound waves or radio waves. As shown in FIG. 1, the electronic tag 20 includes a receiving circuit r1 that receives an individual identification signal transmitted from the transmitting device 10, an optical sensor 22 that receives light from the spotlight 33, and an output from the receiving circuit r1. The control circuit C1 that receives the signal and the output signal from the optical sensor 22 and controls the input signal to the sound wave generator 23, and the sound wave generator 23 that receives the output signal from the control circuit C1 and outputs a predetermined sound wave Prepare. As shown in FIG. 1, the illuminating device 30 determines the position of the sound source from one microphone M1 that receives the sound wave output from the electronic tag 20 and the difference between the output signals when the microphone M1 is shaken up and down and left and right. The sound source estimation circuit 31 to estimate, the sound wave analysis circuit 32 to estimate the light received by the optical sensor 22 from the output signal from the microphone M1, and the output signals from the sound wave estimation circuit 31 and the sound wave analysis circuit 32, The control circuit C2 that controls the light emitted from the spotlight 33 and the actuator (irradiation position varying means) 1a that changes the position of the spotlight 33 in the vertical direction in response to the output signal from the control circuit C2 and the spotlight 33 And a control circuit C3 that controls an actuator (irradiation position varying means) b1 that changes the position in the left-right direction.

  The configuration shown in FIG. 1 increases or decreases the diameter of the light as means for controlling the light emitted from the spotlight 33. Further, the operation of the diameter of the light emitted from the spotlight 33 is terminated at a predetermined maximum value or minimum value.

  The configuration shown in FIG. 1 can receive a sound wave emitted from the electronic tag 20 to estimate the position of the electronic tag 20 and irradiate the electronic tag 20 with the spotlight 33 from the illumination device 30. 20 locations can be found.

FIG. 2 shows an embodiment of a search object detection system using two microphones.
As shown in FIG. 3, the transmitting device 10 includes a button 11 corresponding to the electronic tag 20 attached to the search object, and a transmitting circuit 12 that transmits an individual identification signal to the electronic tag 20 using sound waves or radio waves. As shown in FIG. 3, the electronic tag 20 includes a receiving circuit r1 that receives an individual identification signal transmitted from the transmitting device 10, an optical sensor 22 that receives light from the spotlight 33, and an output from the receiving circuit r1. The control circuit C1 that receives the signal and the output signal from the optical sensor 22 and controls the input signal to the sound wave generator 23, and the sound wave generator 23 that receives the output signal from the control circuit C1 and outputs a predetermined sound wave Prepare. As shown in FIG. 3, the lighting device 30 includes a receiving circuit r2 that receives an individual identification signal transmitted from the transmitting device 10, two microphones M1 and M2 that receive sound waves output from the electronic tag 20, and a reception circuit. Using the output signal of the circuit r2 as a trigger signal, the sound source estimation circuit 31 that estimates the position of the sound source from the difference between the output signals from the microphones M1 and M2, and the optical sensor 22 described above from the output signal from the microphone M1 or M2 A sound wave analysis circuit 32 that estimates the received light, a control circuit C2 that controls the light emitted from the spotlight 33 in response to output signals from the sound wave estimation circuit 31 and the sound wave analysis circuit 32, and an output from the control circuit C2 In response to the signal, an actuator (irradiation position varying means) 1a for changing the position of the spotlight 33 in the vertical direction and the spotlight. Actuators for changing the position of the bets 33 in the left-right direction and a control circuit C3 that controls (irradiation position changing means) b1.

  The configuration shown in FIG. 2 includes at least two microphones M1 and M2 in the lighting device 30, and does not require time and effort to move the microphone up and down and left and right as compared with the case of only one microphone M1. Can be estimated. For example, when the sound wave is a tone burst signal, the distance to the sound source is measured by measuring the arrival time and the arrival time difference between the sound waves reaching the microphones M1 and M2, using the output signal of the receiving circuit r2 as a trigger signal. And the direction of the sound source can be estimated. When the sound wave is a continuous signal, the distance to the sound source and the direction of the sound source can be estimated by measuring the level and level difference of the sound waves that reach the microphones M1 and M2. When no sound wave is generated from the sound source, the noise received by the microphones M1 and M2 is compared to cancel the noise and improve the S / N ratio of the sound wave signal from the sound source. Can do.

  Thus, the position of the sound source can be captured more accurately by using a plurality of microphones. For example, in order to dispose the lighting device 30 in the center of the room and catch sound waves from all directions in the room, it is preferable to include three microphones at intervals of 120 degrees with respect to the rotation axis of the lighting device 30. .

  FIG. 3 schematically shows the above-described embodiment. By pressing a button corresponding to the electronic tag 20 attached to the search object from the radio wave transmission device 10 which is a wireless remote controller, the electronic tag 20 is displayed. This is an example in which the spotlight 33 is irradiated to the position where the electronic tag 20 is present from the illumination device 30 previously installed at a predetermined location in accordance with the sound wave generated from the electronic tag 20.

  FIG. 4 is a flowchart showing a procedure for identifying the position of the electronic tag 20 attached to the search object and irradiating the electronic tag 20 with the spotlight 33.

  Here, the use example of the present invention will be described with reference to the above flowchart in an example in which a search object is detected in a newspaper in a residential room and this search object is detected.

  First, when the button 11 of the wireless controller 10 corresponding to the electronic tag 20 attached to the search object is pressed, an individual identification signal is transmitted to the electronic tag 20 (S1).

  The electronic tag 20 that has received the individual identification signal transmitted from the wireless controller 10 activates the control circuit C1 and takes the output signal of the optical sensor 22 into the control circuit C1. The control circuit C <b> 1 controls the sound wave generator 23 to generate sound waves corresponding to the output signal of the optical sensor 22. In the initial state, since no light is emitted from the spotlight 33, the output signal of the optical sensor 22 becomes a reference output signal corresponding to the location of the electronic tag 20, and the sound wave generator 23 outputs the reference output from the optical sensor 22. A reference sound wave corresponding to the signal is generated. (S2) Here, the control circuit C1 stores the reference output signal from the optical sensor 22 as an initial value.

  The two microphones M1 and M2 provided at predetermined intervals in the illumination device 30 previously installed at a predetermined external location each receive the reference sound wave. The sound source estimation circuit 31 provided in the illumination device 30 estimates the position of the sound source from the difference between the reference output signals from the two microphones M1 and M2 (S3). The sound wave analysis circuit 32 provided in the illumination device 30 estimates the light received by the optical sensor 22 from the reference output signals from the two microphones M1 and M2. Here, the control circuit C2 stores the reference output signal from the sound wave analysis circuit 32 as an initial value.

  The two actuators a1 and b1, which are illumination position varying means, direct the spotlight 33 toward the estimated sound source direction and irradiate light. In the initial state, the diameter of light emitted from the spotlight 33 is set to a predetermined size (S4).

Then, the control circuit C1 of the electronic tag 20 determines whether or not the light from the spotlight 33 has changed compared to the initial value (whether or not the light sensor 22 has received the light from the spotlight 33), and the sound wave The sound wave generated from the generator 23 is controlled.
The control circuit C2 of the lighting device 30 determines whether or not the sound from the electronic tag 20 has changed compared to the initial value (whether or not the sound wave analysis circuit 32 has determined that the light sensor 22 has received the light from the spotlight 33). ). (S5).

  When the electronic tag 20 receives the light emitted from the spotlight 33, the sound generated from the electronic tag 20 changes. Therefore, the spotlight 33 is used until the sound generated from the electronic tag 20 further changes. The position of the electronic tag 20 is specified by reducing the diameter of the light irradiated from 33 (S6, S7).

  Here, when the diameter of the light emitted from the spotlight 33 is reduced, and the electronic tag 20 does not receive the light emitted from the spotlight 33, the spotlight 33 appropriately moves its irradiation position ( (S9), the irradiation position where the sound generated from the electronic tag 20 changes is found, and the location of the electronic tag 20 is specifically identified by the light of the spotlight (S10).

  If the search item is hidden in the newspaper, the spotlight will illuminate it, so the search item can be found by removing the newspaper. If the diameter of the spotlight 33 is larger than a predetermined maximum value, the operation ends (S6).

  On the other hand, if there is no change in the sound wave generated from the electronic tag 20, the diameter of the light emitted from the spotlight 33 is increased (S12), and it is verified whether there is a change in the sound wave generated from the electronic tag 20 (S13). ). If the diameter of the spotlight 33 is smaller than a predetermined maximum value, the operation ends (S11). When the sound changes, the process proceeds to step S6, and when the sound wave generated from the electronic tag 20 is changed, the diameter of the light emitted from the spotlight 33 is reduced (S7), thereby the location of the electronic tag 20 The position is specified (S8 to S10).

  In this way, this search object detection system can detect the search object intuitively by specifying the spot of the search object (squeezing) by applying the spotlight 33 to the search object without wearing a special device.

  Since the sound and light change depending on the location of the electronic tag 20, the present invention has a pleasant element, and as an application, it is possible to search for a search object while being intuitive and enjoyable, or as a toy. There is also.

  The present invention is not limited to the embodiment described above. For example, in the above-described embodiment, it has been described that the location of the electronic tag 20 is specified by changing the diameter of the light irradiated from the spotlight 33. However, the present invention is the intensity of the light irradiated from the spotlight 33. Or you may change the frequency of light suitably. Moreover, although the illuminating device 30 demonstrated in one example, it is also possible to irradiate light with the spotlight 33 from a different direction using two or more illuminating devices 30. FIG.

  For example, the lighting device receives a sound wave generated from an electronic tag and irradiates the spotlight with a predetermined size, then reduces the spotlight diameter and swings the irradiation direction to narrow the position of the electronic tag, One of the actions to search for the electronic tag is performed while increasing the diameter of the light. For example, by reflecting this difference in operation in terms of the frequency of light and reflecting it in the spotlight, the user can determine whether there is an electronic tag in the currently illuminated spotlight, whether it is hidden or hidden. It becomes possible to know by color. Such information is useful for the user who searches, and can find the search faster.

  In the embodiment described above, the frequency of the sound wave generated from the electronic tag 20 is not specified. Sound waves are divided into low frequencies, audio frequencies, and ultrasonic waves according to their frequency ranges, and each has different characteristics. For example, the low frequency has a property of being easily transmitted through a shield, and it is easy to find the electronic tag 20 in a hidden place. For example, the ultrasonic wave has a short wavelength and an excellent selectivity, and the position detection accuracy of the electronic tag 20 can be improved. For this reason, it is possible to more reliably obtain the position information of the electronic tag by combining the frequencies of a plurality of frequency ranges. Thus, it goes without saying that the present invention can be modified as appropriate without departing from the spirit of the present invention.

It is a lineblock diagram of a search thing detection system shown as an embodiment of the invention. It is a block diagram of the same thing detection system. It is a schematic diagram of the usage example of the search object detection system. It is a flowchart explaining a series of processes in the search object detection system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Transmission apparatus 11 Button 12 Transmission circuit 20 Electronic tag 22 Optical sensor 23 Sound wave generator 30 Illumination apparatus 31 Sound source estimation circuit 32 Sound wave analysis circuit 33 Spot light r1, r2 Reception circuit C1, C2, C3 Control circuit M1, M2 Microphone a1, a2 Actuator (irradiation position variable means)
40 detection means

Claims (4)

An electronic tag attached to a search object, a transmitting device for transmitting a transmission wave to the electronic tag, and an illumination device having a spotlight for irradiating light,
If the originating device transmits a transmission wave to the electronic tag, the electronic tag emits sound waves received the transmitted wave, the lighting device is configured to receive the sound waves which the electronic tag is emitted by the microphone, the microphone receives A spot detection method, characterized in that the spotlight emits light in the direction of the sound source of the sound wave,
The electronic tag includes an optical sensor that receives light from the spotlight, and appropriately changes the frequency, sound pressure, or period of sound generated according to the light from the spotlight received by the optical sensor. To change,
The illuminating device appropriately changes the diameter of light emitted from the spotlight, the intensity of light, or the frequency of light according to a change in sound waves of an electronic tag received by the microphone. Detection method. An electronic tag attached to a search object, a transmission device that transmits a transmission wave to the electronic tag, and an illumination device that has a spotlight that emits light, and the electronic tag receives a transmission wave from the transmission device A receiving circuit; and a sound wave generator that generates sound waves, wherein the lighting device includes an irradiation position varying unit that changes an irradiation position of the spotlight, a microphone that receives sound waves from the electronic tag, and a sound source. And a sound source estimation circuit for estimating the distance and the direction of the sound source,
The electronic tag includes an optical sensor that receives light from the spotlight, and a control circuit that controls the sound wave generator from an output signal of the optical sensor, and is generated according to the light of the spotlight. The frequency, sound pressure, or sound cycle of the sound wave is appropriately changed.
The lighting device includes a sound wave analysis circuit that analyzes a change in sound waves from the sound wave generator, and a control circuit that controls the spotlight from an output signal of the sound wave analysis circuit, and a sound wave generated from the electronic tag A search object detection system, wherein the diameter, intensity, or frequency of light emitted from the spotlight is appropriately changed in accordance with the change of the spotlight. The lighting device, in the initial state, the spotlight predetermined for predetermined diameter of the light irradiated from the size Satoshi, the diameter of the light irradiated from the spotlight when there is no change of the sound waves generated from the electronic tag was larger than the predetermined diameter, according to claim 2, characterized in that to reduce the diameter of the light irradiated from the spotlight when there changes in the acoustic wave generated from the electronic tag by which this increased Search system. In the initial state, the illumination device sets the diameter of light emitted from the spotlight to a predetermined size, and if there is a change in sound waves generated from the electronic tag, the illumination device emits light from the spotlight. The search object detection system according to claim 2 , wherein the diameter is reduced.

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