JP2023095500A - Facial image acquisition system, and control method and control program for facial image acquisition system - Google Patents

Abstract

To provide a facial image acquisition system, a control method and a control program of the facial image acquisition system which can acquire a camera image necessary for highly accurately executing face authentication in comparison to a conventional technique.SOLUTION: A facial image acquisition system 10 includes a camera 11, a light guide plate 12, an LED 13 and a control device 20. The camera 11 is installed for imaging a person and performs imaging within a prescribed imaging range. The light guide plate 12 is provided at a position adjacent to the imaging side of the camera 11, internally reflects light incident from a prescribed direction, emits the reflected light from a second surface 12c on the opposite side from a first surface 12b facing the camera 11 to perform the desired display, and is optically transmissive. The LED 13 makes the light incident from the prescribed direction on the light guide plate 12. The control device 20 transmits, to the LED 13, a pulse signal for repeating turn-on and turn-off at a prescribed interval and controls the LED 13 so as to cause the LED 13 to emit light according to the pulse signal.SELECTED DRAWING: Figure 2

Description

The present invention relates to a face image acquisition system using a camera, a control method of the face image acquisition system, and a control program.

2. Description of the Related Art In recent years, camera systems that perform face authentication and attribute discrimination using surveillance cameras have been developed for crime prevention and digital marketing.
For example, in Japanese Unexamined Patent Application Publication No. 2002-100002, in order to photograph a person's face from the front, a switch signal is input from one of the push button switches to a control device when an incident or the like occurs. Disclosed is a facial image acquisition system that generates sound, light, etc. from an installed induction signal generator.

JP-A-7-38786 JP 2011-195227 A JP-A-11-341481

However, the above conventional monitoring system has the following problems.
That is, in the monitoring system disclosed in the above-mentioned publication, in order to photograph a person's face from the front, it emits sound and light from the direction of the monitoring camera to direct the person's face, but the face recognition is performed accurately. There is a risk that the necessary camera images cannot be acquired reliably.
An object of the present invention is to provide a face image acquisition system capable of acquiring a camera image required to perform face authentication with higher accuracy than before, a control method for the face image acquisition system, and a control program. be.

A face image acquisition system according to a first invention includes a camera, a light guide plate, a first light source section, and a control section. A camera is installed to photograph a person and takes an image of a predetermined imaging range. The light guide plate is provided at a position adjacent to the imaging side of the camera, and internally reflects light incident from a predetermined direction so that the light is emitted from the second surface opposite to the first surface facing the camera. In addition to performing desired display, it has optical transparency. The first light source unit causes light to enter the light guide plate from a predetermined direction. The control unit transmits a pulse signal for repeating lighting and extinguishing at a predetermined interval to the first light source unit, and controls the first light source unit so that light is emitted from the first light source unit according to the pulse signal. do.

Here, a light guide plate (STP) is installed at a position adjacent to the photographing side (lens side) of the camera. The first light source section is controlled so as to irradiate light from the section.
Here, the camera includes, for example, various cameras installed for crime prevention, monitoring, watching, and marketing. The information obtained by the camera includes, for example, behavioral information of people acting suspiciously, wandering behavior of elderly people, people stopping in front of specific products in department stores, and the like.

For example, the light guide plate internally reflects light incident from an incident surface such as an end face and emits the light from the exit surface, thereby providing a specific display (interesting information, advertisement, etc.) when viewed from the exit surface side. display. In addition, since the light guide plate is light transmissive, the camera arranged adjacent to the first surface side can be visually recognized when viewed from the second surface side in a state where light is not incident.
The first light source unit is, for example, an LED (Light Emitting Diode), and irradiates the incident surface of the light guide plate with light.

The control unit controls the first light source unit based on the predetermined pulse signal so that the first light source unit is repeatedly turned on/off at predetermined intervals that cannot be recognized by human beings, for example.
Thereby, by controlling the first light source unit and performing desired display on the light guide plate in accordance with a predetermined pulse signal for a person in the shooting range of the camera, a target person (for example, a suspicious person, a person watching over the person, etc.) It is possible to attract the attention of the target person, the marketing target person, etc., and induce them to turn around in the direction of the light guide plate.

In addition, by causing the display unit to perform a specific display based on the pulse signal, for example, by acquiring an image with the camera at a timing when light is not emitted from the first light source unit, the light from the first light source unit A clearer image can be obtained without being affected by
Therefore, the camera arranged adjacent to the first surface side of the light guide plate can capture the face of the target person almost from the front and acquire an image with reduced influence of light. Appropriate face images used for discrimination can be obtained.
Furthermore, it is difficult for the target person who sees the light guide plate to visually recognize the camera arranged adjacent to the back side (first surface) of the light guide plate when a specific display is displayed on the light guide plate.
As a result, it is possible to acquire a camera image necessary for performing face authentication with higher accuracy than in the past.

A face image acquisition system according to a second invention is the face image acquisition system according to the first invention, wherein the image is acquired from the camera at the timing when the light emitted from the first light source is turned off. An acquisition unit is further provided.
As a result, the first light source unit is controlled to irradiate the light guide plate with light in a time-sharing manner to the person in the photographing range of the camera, and at the timing when the first light source unit does not irradiate the light. By acquiring an image with the camera, a clearer image can be acquired without being affected by the light from the first light source.

A facial image acquisition system according to a third aspect is the facial image acquisition system according to the first or second aspect, wherein the light guide plate receives the light emitted from the first light source unit, the second surface To display a pattern that attracts people's attention when viewed.
As a result, the attention of the target person (for example, a suspicious person, a person to be watched over, a person to be marketed, etc.) is attracted by displaying a pattern on the light guide plate that attracts the attention of the person in the shooting range of the camera. Therefore, the direction of the light guide plate can be effectively turned.

A facial image acquisition system according to a fourth invention is the facial image acquisition system according to any one of the first to third inventions, wherein the light guide plate receives light emitted from the first light source unit. , the camera is rendered invisible when viewed from the second surface.
As a result, for example, even when a target person such as a suspicious person or an elderly person to be watched over looks in the direction of the light guide plate, the camera arranged adjacent to the back side of the light guide plate cannot be visually recognized. It is possible to avoid giving discomfort to the target person by noticing.

A facial image acquisition system according to a fifth aspect is the facial image acquisition system according to any one of the first to fourth aspects, wherein the light guide plate receives light emitted from the first light source unit. When not in position, the camera is visible when viewed from the second side.
Accordingly, when light is not incident from the first light source section, the presence of the camera arranged on the back side (first surface) can be visually recognized through the light guide plate. Therefore, since the camera can be visually recognized in a state in which no specific display is made on the light guide plate, a crime deterrent effect can be obtained by installing the camera.

A facial image acquisition system according to a sixth aspect of the invention is the facial image acquisition system according to any one of the first to fourth aspects of the invention, wherein the facial image acquisition system is provided between the light guide plate and the camera. It also has a smoke plate that makes the camera invisible when viewed from two sides.
As a result, regardless of the presence or absence of display on the light guide plate (turning on/off the first light source unit), the smoke plate is provided so that the camera cannot be seen, so the person being photographed by the camera feels uncomfortable. can be avoided.

A facial image acquisition system according to a seventh invention is the facial image acquisition system according to any one of the first to sixth inventions, wherein the controller comprises a first mode for turning off the first light source, and a second mode for lighting the first light source.
Thus, by switching between the first mode and the second mode according to the information acquired from the camera, the light from the first light source unit is turned on and off, thereby displaying/displaying a specific display on the light guide plate. Can be toggled hidden.

A facial image acquisition system according to an eighth aspect of the invention is the facial image acquisition system according to the seventh aspect, wherein the control unit, when the image obtained from the camera includes a person who seems to be a predetermined target person, selects the second mode to emit light from the first light source unit to the light guide plate.
As a result, for example, when a camera image includes a target person registered as a suspicious person, an elderly person who is likely to wander around, a target person for marketing, etc., in the second mode, a specific display is performed on the light guide plate. By performing , the face of the subject can be directed toward the light guide plate, and the face image can be obtained from the front.

A face image acquisition system according to a ninth invention is the face image acquisition system according to any one of the first to eighth inventions, wherein the behavior of a person within the imaging range of the camera is monitored and the person is monitored. A person behavior monitoring unit for determining whether or not the person is an appropriate person is further provided.
As a result, for example, by monitoring the behavior of a suspicious person such as a person who has repeatedly visited the same place, if the person is determined to be a person to be monitored, the light guide plate will be displayed for that person. A face image can be acquired in a state in which a specific display is performed and the user is turned around.

A facial image acquisition system pertaining to a tenth invention is the facial image acquisition system pertaining to any one of the first to ninth inventions, wherein the control unit responds to the attributes of the person looking at the direction of the camera. The first light source section is controlled to perform a specific display.
As a result, for example, when a light guide plate is installed as a display for a specific product in a department store, etc., an effective display of advertisements, etc., can be displayed in accordance with the attributes of a person who is interested in the specific product and stops. It can be performed.

A facial image acquisition system according to an eleventh aspect is the facial image acquisition system according to the tenth aspect, wherein the specific display includes advertisements and information of interest to the person.
As a result, for example, when a light guide plate is installed as a display for a specific product in a department store, the light guide plate displays advertisements and information that attract the interest of a person who is interested in the specific product and stops. By doing so, a more effective advertising effect can be obtained.

A facial image acquisition system according to a twelfth invention is the facial image acquisition system according to any one of the first to eleventh inventions, and is arranged on the first surface side of the light guide plate, and It further comprises a second light source unit that emits a flash light that causes the light to flow.

As a result, since the second light source unit for irradiating flash light is provided on the first surface side of the light guide plate adjacent to the camera, in addition to the display on the light guide plate, the stimulus by the flash light also enables the imaging range. A person inside can be made to turn toward the light guide plate.
In addition, since the second light source unit is also arranged on the back (first surface) side of the light guide plate like the camera, even if the subject turns toward the light guide plate, it avoids discomfort. can do.

A facial image acquisition system according to a thirteenth invention is the facial image acquisition system according to any one of the first to twelfth inventions, wherein the lens of the camera is provided on the first surface of the light guide plate and emits light. It is arranged so as to be adjacent to an area where no reflective microprisms are arranged.
As a result, a clear face image can be acquired by the camera without being affected by the fine prisms.

A facial image acquisition system according to a fourteenth invention is the facial image acquisition system according to any one of the first to thirteenth inventions, wherein the controller switches the direction of light incident on the light guide plate. to switch between a plurality of patterns displayed on the light guide plate.
As a result, when a specific display is displayed on the light guide plate and the target person is turned around, by switching and displaying a more interesting pattern, it is possible to make the target person gaze at the direction of the light guide plate, which is more effective. Typically, a camera can acquire a facial image of a subject.

A face image acquisition system pertaining to a fifteenth invention is the face image acquisition system pertaining to the fourteenth invention, wherein a plurality of face images are arranged inside the light guide plate in a state in which a person's face can be recognized from the camera through the light guide plate. Fine prisms corresponding to the design are arranged in a plurality of patterns.
As a result, while ensuring that the camera can recognize the face of the subject through the light guide plate, since the fine prisms are provided in a plurality of patterns, it is possible to switch between a plurality of displays on the light guide plate.

A facial image acquisition system according to a sixteenth invention is the facial image acquisition system according to any one of the first to fifteenth inventions, wherein sound information is output in accordance with display content displayed on the light guide plate. A sound output section is further provided.
Thus, in addition to the display on the light guide plate, the sound information stimulates the person within the shooting range to turn toward the light guide plate.

A facial image acquisition system according to a seventeenth invention is the facial image acquisition system according to any one of the first to sixteenth inventions, wherein the facial recognition of the person captured by the camera exceeds a predetermined judgment value. It further includes a face authentication propriety determination unit that determines whether or not the face authentication has occurred.
As a result, by determining whether or not the face image acquired by the above-described face image acquisition system is suitable for face authentication, for example, a face image that can be used for face authentication is obtained. By performing control such as switching the display of the light plate, a face image suitable for face authentication can be obtained more reliably.

A facial image acquisition system according to an eighteenth aspect is the facial image acquisition system according to the seventeenth aspect, wherein the control unit counts the number of times the determination result of the face authentication propriety determination unit is invalid, and The first light source section is controlled to switch the display of the light guide plate until the number of times exceeds a predetermined number of times.
As a result, until the number of times the face image acquired by the above-described face image acquisition system is judged to be an image suitable for face recognition as being unacceptable exceeds a predetermined number of times, the light guide plate is repeatedly operated. By switching the display of , acquisition of a preferable face image of the subject can be attempted.

A facial image acquisition system according to a nineteenth invention is the facial image acquisition system according to the eighteenth invention, wherein a storage unit for storing a specific person's facial image in advance and a judgment result in the face authentication propriety judgment unit are determined. A person collation unit is further provided for collating the face image of the person captured by the camera with the face image of the specific person stored in the storage unit when the value is greater than or equal to the value.
As a result, by comparing the face image stored in the storage unit with the face image acquired by the face image acquisition system, for example, a target person registered as a suspicious person or an elderly person who may be wandering It can be determined whether or not there is a match with the face.

A facial image acquisition system according to a twentieth aspect of the invention is the facial image acquisition system according to the nineteenth aspect of the invention, in which the facial image of the person captured by the camera and the previously stored specific The apparatus further includes an alarm unit that issues an alarm when it is determined that the facial image matches the person's face image.
As a result, when the result of determination by the person verification unit is that the person matches a specific person, for example, by issuing an alarm such as informing the manager of the facility, it is possible to take appropriate measures.

A control method for a facial image acquisition system according to a twenty-first invention is a control method for controlling the facial image acquisition system according to any one of the first to twentieth inventions, wherein a predetermined imaging range is captured by a camera. an image acquiring step of acquiring an image obtained by acquiring a captured image; and transmitting a pulse signal for repeating lighting and extinguishing at a predetermined interval to the first light source unit, causing the first light source unit to irradiate light according to the pulse signal, and guiding the light. and a display step of performing desired display when viewed from the second surface side of the light plate.

Here, a light guide plate (STP) is installed at a position adjacent to the photographing side (lens side) of the camera. The first light source section is controlled so as to irradiate light from the section.
Here, the camera includes, for example, various cameras installed for crime prevention, monitoring, watching, and marketing. The information obtained by the camera includes, for example, behavioral information of people acting suspiciously, wandering behavior of elderly people, people stopping in front of specific products in department stores, and the like.

For example, the light guide plate internally reflects light incident from an incident surface such as an end face and emits the light from the exit surface, thereby providing a specific display (interesting information, advertisement, etc.) when viewed from the exit surface side. display. In addition, since the light guide plate is light transmissive, the camera arranged adjacent to the first surface side can be visually recognized when viewed from the second surface side in a state where light is not incident.
The first light source unit is, for example, an LED (Light Emitting Diode), and irradiates the incident surface of the light guide plate with light.

The control unit controls the first light source unit based on the predetermined pulse signal so that the first light source unit is repeatedly turned on/off at predetermined intervals that cannot be recognized by human beings, for example.
Thereby, by controlling the first light source unit and performing desired display on the light guide plate in accordance with a predetermined pulse signal for a person in the shooting range of the camera, a target person (for example, a suspicious person, a person watching over the person, etc.) It is possible to attract the attention of the target person, the marketing target person, etc., and induce them to turn around in the direction of the light guide plate.

In addition, by causing the display unit to perform a specific display based on the pulse signal, for example, by acquiring an image with the camera at a timing when light is not emitted from the first light source unit, the light from the first light source unit A clearer image can be obtained without being affected by
Therefore, the camera arranged adjacent to the first surface side of the light guide plate can capture the face of the target person almost from the front and acquire an image with reduced influence of light. Appropriate face images used for discrimination can be obtained.
Furthermore, it is difficult for the target person who sees the light guide plate to visually recognize the camera arranged adjacent to the back side (first surface) of the light guide plate when a specific display is displayed on the light guide plate.
As a result, it is possible to acquire a camera image necessary for performing face authentication with higher accuracy than in the past.

A control program for a facial image acquisition system according to a twenty-second invention is a control program for controlling the facial image acquisition system according to any one of the first to twentieth inventions, wherein a predetermined imaging range is imaged from a camera. an image acquiring step of acquiring an image obtained by acquiring a captured image; and transmitting a pulse signal for repeating lighting and extinguishing at a predetermined interval to the first light source unit, causing the first light source unit to irradiate light according to the pulse signal, and guiding the light. and a display step of performing a desired display when viewed from the second surface side of the light plate.

Here, a light guide plate (STP) is installed at a position adjacent to the photographing side (lens side) of the camera. The first light source section is controlled so as to irradiate light from the section.
Here, the camera includes, for example, various cameras installed for crime prevention, monitoring, watching, and marketing. The information obtained by the camera includes, for example, behavioral information of people acting suspiciously, wandering behavior of elderly people, people stopping in front of specific products in department stores, and the like.

For example, the light guide plate internally reflects light incident from an incident surface such as an end face and emits the light from the exit surface, thereby providing a specific display (interesting information, advertisement, etc.) when viewed from the exit surface side. display. In addition, since the light guide plate is light transmissive, the camera arranged adjacent to the first surface side can be visually recognized when viewed from the second surface side in a state where light is not incident.
The first light source unit is, for example, an LED (Light Emitting Diode), and irradiates the incident surface of the light guide plate with light.

The control unit controls the first light source unit based on the predetermined pulse signal so that the first light source unit is repeatedly turned on/off at predetermined intervals that cannot be recognized by human beings, for example.
Thereby, by controlling the first light source unit and performing desired display on the light guide plate in accordance with a predetermined pulse signal for a person in the shooting range of the camera, a target person (for example, a suspicious person, a person watching over the person, etc.) It is possible to attract the attention of the target person, the marketing target person, etc., and induce them to turn around in the direction of the light guide plate.

In addition, by causing the display unit to perform a specific display based on the pulse signal, for example, by acquiring an image with the camera at a timing when light is not emitted from the first light source unit, the light from the first light source unit A clearer image can be obtained without being affected by
Therefore, the camera arranged adjacent to the first surface side of the light guide plate can capture the face of the target person almost from the front and acquire an image with reduced influence of light. Appropriate face images used for discrimination can be obtained.

Furthermore, it is difficult for the target person who sees the light guide plate to visually recognize the camera arranged adjacent to the back side (first surface) of the light guide plate when a specific display is displayed on the light guide plate.
As a result, it is possible to acquire a camera image necessary for performing face authentication with higher accuracy than in the past.

According to the face image acquisition system of the present invention, it is possible to acquire a camera image necessary for performing face authentication with higher accuracy than in the past.

1 is a system configuration diagram showing the configuration of a face image acquisition system according to an embodiment of the present invention; FIG. FIG. 2 is a conceptual diagram showing an arrangement example of a camera, a light guide plate, LEDs, a control device, etc. included in the face image acquisition system of FIG. 1; FIG. 2 is an enlarged conceptual diagram showing a configuration around an LED and a light guide plate included in the face image acquisition system of FIG. 1; FIG. 2 is a control block diagram of the face image acquisition system of FIG. 1; FIG. 3 is a schematic diagram showing a normal state under the face image acquisition system of FIG. 2; FIG. 3 is a schematic diagram showing a warning state under the face image acquisition system of FIG. 2; 4 is a graph showing pulse signals transmitted by pulse drive control for LEDs and cameras in the face image acquisition system of FIG. 1; 2 is a flow chart showing the flow of processing of a control method for the face image acquisition system in the face image acquisition system of FIG. 1; 2 is a flow chart showing the flow of processing of a control method for the face image acquisition system in the face image acquisition system of FIG. 1; FIG. 10 is a conceptual diagram showing an arrangement example of a camera, a light guide plate, LEDs, a flashlight, a speaker, a control device, etc. included in a facial image acquisition system according to another embodiment of the present invention; FIG. 10 is a conceptual diagram showing an arrangement example of a camera, a light guide plate, an LED, a smoke plate, a control device, etc. included in a face image acquisition system according to still another embodiment of the present invention; FIG. 10 is a conceptual diagram showing an arrangement example of a camera, a light guide plate, LEDs, a control device, etc. included in a facial image acquisition system according to still another embodiment of the present invention;

A facial image acquisition system according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 9. FIG.
In addition, in this embodiment, more detailed description than necessary may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid unnecessary verbosity in the following description and to facilitate understanding by those skilled in the art.
Applicants also provide the accompanying drawings and the following description for a full understanding of the invention by those skilled in the art, and are not intended to limit the claimed subject matter thereby. do not have.

(1) Configuration of Face Image Acquisition System 10 The face image acquisition system 10 according to the present embodiment includes, for example, a plurality of cameras for monitoring an unspecified number of people installed in shops, facilities, shopping streets, etc. A system for acquiring a face image including the face of a person who is in the store or the like using a camera, and as shown in FIG. A face image DB (storage unit) 31 , an administrator terminal 32 , a terminal device 33 , and a management information bus 40 are provided.

A plurality of cameras 11 are installed in areas where monitoring and watching are performed in shops, facilities, etc., and the images (videos) captured by each camera 11 are stored in the control device 20 as shown in FIG. It is acquired by the image acquisition unit 21 .
The control device 20 includes at least an image acquisition unit 21 corresponding to each of the plurality of cameras 11, a person verification unit 28, and a warning generation unit 30, as shown in FIG.

The image acquisition unit 21 acquires images (videos) captured by a plurality of cameras 11 and transmits them to the person verification unit 28 via the management information bus 40 . In addition, the image acquisition unit 21 detects the light in the camera 11 at the timing when the LED (Light Emitting Diode) (first light source unit) 13, which is time-divisionally controlled to repeat turning on and off by the light source control unit 26, which will be described later, is turned off. To acquire only an image at the time of lights out from among continuously photographed images.

The person verification unit 28 receives images captured by the plurality of cameras 11 via the image acquisition unit 21 and compares the images with the face images of a specific target person stored in the face image DB 31 to determine whether or not they match. judge. As a result, by comparing an image captured using a plurality of cameras 11 installed in a facility or the like with a face image of a specific person registered in advance in the face image DB 31, it is possible to easily determine whether or not they match. can judge.

The warning generating section 30 is connected to the person matching section 28 as shown in FIG. Then, the warning generating unit 30 uses the result of the collation by the person collating unit 28, for example, a person registered as a suspicious person, an elderly person registered as likely to wander, or a resident or staff member of an elderly facility or the like. When a suspicious person who does not match a registrant such as a security guard is found, a warning that a suspicious person has been found is sent to the administrator's terminal 32, the terminal device 33 owned by the staff of the facility, or the like.

Note that FIG. 1 shows only the main configuration of the control device 20, and the detailed configuration of the control device 20 will be described later.
As shown in FIG. 1, the face image DB 31 is connected to the person matching unit 28, and includes the faces of pre-registered target persons (suspicious persons to be monitored, elderly persons to be watched over, residents and staff of facilities, etc.). saving the image.

In particular, the face image acquisition system 10 of the present embodiment requires a large number of face images of persons to be monitored, etc., in order to compare with a large number of images captured by a plurality of cameras 11 installed in shops, facilities, and the like. Therefore, the face image DB 31 stores a large number of face image data of persons to be monitored.
The administrator terminal 32 is a PC (Personal Computer) owned by an administrator of the facility, and is connected to the warning generator 30 as shown in FIG. .

The terminal device 33 is a portable terminal owned by each staff member of the facility, and is connected to the warning generator 30 as shown in FIG. .
As a result, when a suspicious person or an elderly person to be watched over is found from the image of the camera 11, an alert signal is transmitted to the administrator terminal 32 or the terminal device 33, thereby can promptly take appropriate action.

Next, the peripheral configuration of each of the plurality of cameras 11 installed in facilities or the like will be described below.
The facial image acquisition system 10 of this embodiment includes a camera 11, a light guide plate 12, an LED (light source) 13, and a control device 20, as shown in FIG.
The camera 11 is an image capturing device for capturing an image of a person P1 within an image capturing range, and as a general rule, always captures an image within the image capturing space. As shown in FIG. 2, the camera 11 is installed on the ceiling of the facility or the like, and is arranged at a position adjacent to the rear surface (first surface) side of the light guide plate 12 .

As shown in FIG. 2, the light guide plate 12 is arranged adjacent to the photographing side (lens side) of the camera 11, and when the light emitted from the LED 13 is incident, it passes through a predetermined fine prism 12d (see FIG. 3). The light reflected at the second surface 12c is emitted from the second surface 12c, and a pattern or the like is displayed according to the pattern of the fine prisms 12d.
More specifically, the light guide plate 12 has, as shown in FIG. ) 12c and a fine prism 12d.

As shown in FIG. 3, the end surface 12a is arranged at a position facing the LED 13, and the light emitted from the LED 13 is incident thereon.
As shown in FIG. 2, the first surface 12b is a surface of the light guide plate 12 adjacent to the camera 11, and as shown in FIG. 3, fine prisms 12d are formed in a predetermined pattern on the inner surface side. .

As shown in FIG. 3, the second surface 12c is an emission surface on the opposite side of the first surface 12b, and is arranged on the imaging target side of the camera 11. As shown in FIG.
As shown in FIG. 3, the fine prism 12d is formed on the inner surface side of the first surface 12b and has a substantially triangular shape when viewed in cross section. Further, the fine prisms 12d are formed in a predetermined pattern according to the design displayed on the light guide plate 12. FIG.

As a result, the light emitted from the LED 13 and incident from the end surface 12a is reflected by the fine prisms 12d formed in a predetermined pattern, and emitted from the second surface (exit surface) 12c. It is possible to display a pattern or the like.
Here, when the light emitted from the LED 13 is incident on the light guide plate 12 and a pattern or the like is displayed on the light guide plate 12, the camera 11 arranged on the rear side becomes invisible through the light guide plate 12. - 特許庁

As a result, a person who sees the light guide plate 12 on which the pattern or the like is displayed does not notice the presence of the camera 11 on the back side thereof, so that it is possible to avoid making the person feel uncomfortable.
On the other hand, when the LED 13 is not illuminated with light, no pattern or the like is displayed on the light guide plate 12, and the camera 11 arranged on the rear side can be visually recognized through the light guide plate 12 having light transparency. .

Thus, when the LED 13 is extinguished, the existence of the camera 11 on the rear side thereof is recognized through the light guide plate 12, so that the recognition of the existence of the camera 11 can provide a crime deterrent effect.
As shown in FIGS. 2 and 3, the LED 13 is arranged at a position facing the upper end surface 12a of the light guide plate 12, and irradiates the end surface 12a with light. The light emitted from the LED 13 is reflected by a fine prism 12d formed on the inner surface side of the first surface 12b, as indicated by the dashed line in FIG. 3, and emitted from the second surface 12c side toward the shooting space. .

Here, most of the light emitted from the LED 13 is emitted from the second surface 12c side as shown in FIG. 3, but part of it is also emitted from the first surface 12b side. Even a small amount of light emitted from the side of the first surface 12b may degrade the quality of the image captured by the camera 11 arranged adjacent to the first surface 12b.
For this reason, in the facial image acquisition system 10 of the present embodiment, a predetermined pulse signal (see FIG. 5) is transmitted to the LED 13 so that the lighting is controlled in a time-division manner in which the LED 13 is repeatedly turned on and off for a predetermined period of time. It controls the LED 13 . Then, the image acquisition unit 21 acquires an image captured at the timing when the LED 13 is turned off from the camera 11, thereby acquiring a high-definition image without being adversely affected by a small amount of light from the first surface 12b. be able to.

Next, a detailed configuration of the control device 20 will be described below.
As shown in FIG. 4, the control device 20 includes an image acquisition unit 21, a human behavior monitoring unit 22, a face authentication availability determination unit 23, a face authentication failure count unit 24, a count determination unit 25, and a light source control unit. 26 , a face authentication unit 27 , a person matching unit 28 , a determination unit 29 and a warning generation unit 30 .

The image acquisition unit 21 is provided so as to correspond to each of the plurality of cameras 11, as shown in FIG.
In the present embodiment, as described above, the image acquisition unit 21 synchronizes with the LED 13 that is repeatedly turned on and off by the pulse signal shown in FIG. obtained as a face image of

As a result, as shown in FIG. 3, when the LED 13 is turned on, a high-definition image can be captured by the camera 11 without being affected by light leaking out toward the first surface 12b of the light guide plate 12. .
The human behavior monitoring unit 22 is connected to the image acquisition unit 21 as shown in FIG. Specifically, the human behavior monitoring unit 22 acquires an image or the like captured by the camera 11 and monitors whether or not a person included in the image moves suspiciously.

Specifically, the human behavior monitoring unit 22 detects and monitors a person moving back and forth within the imaging range of the camera 11, a person wandering around, etc. as a person moving suspiciously. For example, within a predetermined imaging range, the number of times a specific person makes a round trip within a predetermined time is counted, and when the count value reaches a preset number, the human behavior monitoring unit 22 detects the person. Judged as suspicious behavior.

The face authentication propriety determination unit 23 acquires an image including the face of a person who has been determined to be a suspicious behavior by the human behavior monitoring unit 22, and determines whether or not the image is an image for which face authentication can be performed. judge. Specifically, the face authentication approval/disapproval determination unit 23 performs face authentication approval/disapproval determination according to whether or not the direction of the face of the person included in the image, the illuminance of the image, and the like satisfy predetermined criteria.
The face authentication disapproval counting unit 24 counts the number of times the face authentication approval/disapproval determination unit 23 determines that face authentication is not possible because conditions such as face orientation are not satisfied in face authentication approval/disapproval determination of the same person.

The count determining unit 25 determines whether the number of times counted by the face authentication failure counting unit 24 is less than a predetermined set number of times or more than a predetermined number of times.
For example, when the counted number of times is less than the set number of times, the count value is transmitted to the light source control section 26 . On the other hand, when the counted number of times is greater than or equal to the set number of times, an alert signal is transmitted to the warning generating section 30 .

The light source control unit 26 receives a count value transmitted from the count determination unit 25 when the number of times counted is less than the set number of times, and performs lighting control of the LED 13 according to the count value.
For example, when the set number of times is set to 4 and the count value is 1, the light source control unit 26 performs control to turn on the LED 13 . Further, when the count value is two, the light source control unit 26 performs control to blink the LED 13 at intervals that can be recognized by the human eye. Furthermore, when the count value is 3, the light source control unit 26 increases the current flowing through the LED 13 to perform control to light the LED 13 more brightly.

As a result, the light emitted from the LED 13 enters from the end surface 12a of the light guide plate 12, is reflected by the fine prism 12d, and is emitted from the second surface 12c. can be displayed.
A target person (particularly, a person who is determined to be a suspicious person) within the shooting range of the camera 11 is concerned about the display on the light guide plate 12 by the lighting control of the LED 13 . Therefore, by turning to the direction of the light guide plate 12, the subject faces the camera 11 on the rear side through the light guide plate 12, and the camera 11 can acquire a proper face image.

When the face authentication determination unit 23 determines that face authentication is possible, the face authentication unit 27 uses the face image to perform face authentication so as to calculate the feature amount of the face.
The person matching unit 28 uses the facial feature amount calculated by the face authentication unit 27 to determine whether or not the face of the target person included in the image matches the face of the person registered in advance in the face image DB 31. to match

Here, in the face image DB 31, face image data of a person requiring attention, a suspicious person, etc. is accumulated for comparison with the face of a person included in the image photographed by the camera 11 in real time. Therefore, the person matching unit 28 can match each face image for which face authentication has been performed with the face image stored in the face image DB 31 .
As a result of matching by the person matching unit 28, the determination unit 29 determines that the features of the target person's face photographed by the camera 11 match the features of the face image stored in advance in the face image DB 31 as a person requiring caution, a suspicious person, or the like. determine whether or not to Here, when the degree of coincidence between the two is high, a warning signal is transmitted to the warning generating section 30 .

As a result of determination by the determination unit 29, the warning generation unit 30 determines that the features of the target person's face captured by the camera 11 have a high degree of matching with the features of the face image stored in the face image DB 31. An alert signal is transmitted to the administrator terminal 32 and the terminal device 33 (see FIG. 1).
As a result, the administrator or staff of the facility where the camera 11 is installed recognizes that there is a person requiring caution in the facility by the alert signal received from the warning generation unit 30, and takes appropriate measures. can be done.

<Display Control of Patterns on Light Guide Plate 12>
Display control for attracting the attention of a person within the imaging range of the camera 11 by displaying a pattern or the like on the light guide plate 12 by the facial image acquisition system 10 of the present embodiment will be described with reference to FIGS. 6 and 7. FIG. are as follows:
FIG. 6 shows the state of the control device 20 in the normal mode (first mode).

In the normal mode, the human behavior monitoring unit 22 of the control device 20 shown in FIG. 6 monitors the behavior of the person P1 within the imaging range of the camera 11, and monitors whether there is a suspicious person or the like. .
At this time, the control device 20 is in a light-off state in which light is not emitted from the LED 13, and no pattern or the like is displayed on the light guide plate 12. FIG. Therefore, since the light guide plate 12 is almost transparent when viewed from the person P1 in the shooting range, the camera 11 arranged adjacent to the back side of the light guide plate 12 can be visually recognized.

As a result, since the presence of the camera 11 is recognized, a crime deterrent effect can be obtained in the facility or the like.
FIG. 7 shows the control device 20 in the alert mode (second mode).
In the warning mode, as a result of monitoring the behavior of a person within the photographing range photographed by the camera 11 in the human behavior monitoring unit 22 of the control device 20 shown in FIG. I do.

At this time, the control device 20 is in a lighting state in which light is emitted from the LED 13, and the light guide plate 12 displays, for example, a weather forecast pattern indicating sunny, cloudy, rainy, etc. shown in FIG.
When switching the pattern to be displayed on the light guide plate 12 , for example, the LED 13 that allows light to enter the light guide plate 12 is switched to change the incident direction of the light to the light guide plate 12 . As a result, light can be reflected in different patterns of the fine prisms 12d to switch to a different design.

For example, when the human behavior monitoring unit 22 determines that a suspicious person is present, the light source control unit 26 controls lighting of the LED 13 so that a specific pattern or the like is displayed on the light guide plate 12 for a moment.
As a result, the pattern or the like is momentarily displayed on the light guide plate 12, which was almost transparent in the normal mode, and the person P1 within the shooting range of the camera 11 turns to the light guide plate 12 as shown in FIG. can be directed to

Here, in a state where the LED 13 is lit and the pattern or the like is displayed on the light guide plate 12, the camera 11 on the back side thereof cannot be visually recognized through the light guide plate 12.例文帳に追加Therefore, since the light guide plate 12 is in an opaque state when viewed from a person in the photographing range, the camera 11 arranged adjacent to the back surface (first surface 12b) of the light guide plate 12 cannot be recognized. It is possible to avoid the unpleasant feeling of being photographed by 11.

On the other hand, from the camera 11 arranged on the back side of the light guide plate 12 in the state where the pattern etc. are displayed, the fine prisms 12d included in the light guide plate 12 are very small, so the camera 11 is within the photographing range through the light guide plate 12. You can take pictures of people.
In particular, in this embodiment, by switching and displaying on the light guide plate 12 patterns that attract people's interest, a person looking in the direction of the light guide plate 12 can see the camera arranged adjacent to the back side of the light guide plate 12. 11, the face is almost facing the front.

As a result, the camera 11 can easily acquire a face image that can be used for face authentication, and the accuracy of face authentication can be improved.
Further, in the face image acquisition system 10 of the present embodiment, as described above, it is determined whether or not the image can be used for face authentication, and the number of determinations is counted. to implement.

As a result, a person within the photographing range of the camera 11 can see the light guide plate 12 when the LED 13 is lit for the first time, because the pattern or the like is displayed on the light guide plate 12 in a different lighting pattern until it is determined that the person can be used for face authentication. Even a person who did not see the light guide plate 12 is more likely to see the light guide plate 12 when the LED 13 is turned on for the second time and when the LED 13 is turned on for the third time. Therefore, by controlling the lighting of the LED 13 with different lighting patterns, repeated attempts can be made until a face image determined to be usable for face authentication is obtained.

Further, even when the shooting range of the camera 11 is dark, the lighting of the LED 13 brightens the light guide plate 12, so that the brightness of the light guide plate 12 can be used to shoot an image with the camera 11.例文帳に追加
<Control Method of Face Image Acquisition System 10>
The face image acquisition system 10 of the present embodiment implements the control method of the face image acquisition system 10 according to the flowcharts shown in FIGS. 8 and 9. FIG.

That is, as shown in FIG. 8, in step S11, the human behavior monitoring unit 22 of the control device 20 monitors whether or not there is a person in the shooting range of the camera 11 who is acting suspiciously (see FIG. 8). image acquisition step). Here, if it is determined that there is a person acting suspiciously, the process proceeds to the flow of FIG. 9, and if it is determined that there is no person acting suspiciously, the process proceeds to step S12.
Next, in step S12, the face authentication propriety determination unit 23 determines whether or not the image acquired from the camera 11 by the image acquisition unit 21 can be used for face authentication. Here, if it is determined that it can be used for face authentication, the process proceeds to step S13. On the other hand, if it is determined that the face authentication cannot be used, the process proceeds to step S16.

Next, in step S13, since it is determined in step S12 that the acquired image can be used for face authentication, the face authentication section 27 and the person matching section 28 carry out face authentication and person matching processing.
Next, in step S<b>14 , the determination unit 29 determines whether or not the person whose face has been authenticated in step S<b>13 matches the person requiring caution stored in the face image DB 31 . Here, if they match, the process proceeds to step S15. On the other hand, if it does not match the person requiring caution, the process returns to step S11.

Next, in step S15, since it is determined in step S14 that the person matches the person requiring caution, the warning generation unit 30 transmits an alert signal to the administrator's terminal 32 and the like.
Next, in step S16, since it was determined in step S12 that the acquired image cannot be used for face authentication, the light source control unit 26 controls lighting of the LED 13 (light guide plate 12 display control) (display step).

Next, in step S17, the face authentication availability determination unit 23 determines whether or not the image acquired by the image acquisition unit 21 after lighting control of the LED 13 in step S16 can be used for face authentication. Here, if it is determined that it can be used for face authentication, the process proceeds to step S18. On the other hand, if it is determined that the face authentication cannot be used, the process proceeds to step S20.
Next, in step S18, since it is determined in step S17 that the acquired image can be used for face authentication, the face authentication section 27 and the person matching section 28 carry out face authentication and person matching processing.

Next, in step S<b>19 , the determination unit 29 determines whether or not the person whose face has been authenticated in step S<b>18 matches the person requiring caution stored in the face image DB 31 . Here, if they match, the process proceeds to step S22. On the other hand, if it does not match the person requiring caution, the process returns to step S11.
In step S19, the person determined by the determination unit 29 not to be a person requiring special attention is subjected to face recognition/person verification using an image suitable for face recognition acquired as a result of the display on the light guide plate 12. ing. Therefore, the facial image acquisition system 10 of the present embodiment can derive the result that the person is not a person requiring caution with high accuracy.

Next, in step S20, the face authentication disapproval counting unit 24 counts the number of times the face authentication is judged to be disallowed in step S17.
Next, in step S21, the count determination unit 25 determines whether or not the count value obtained by counting the number of times the facial authentication is determined to be unsuccessful in step S20 is less than a predetermined set value. Here, if it is determined that the count value is less than the predetermined set value, the process returns to step S16 to control lighting of the LED 13 with a different lighting pattern.

Thus, by controlling lighting of the LED 13 with different lighting patterns until a face image determined to be usable for face authentication can be obtained, the possibility of obtaining a face image that can be used for face authentication can be increased.
On the other hand, if it is determined that the count value is equal to or greater than the predetermined set value, the process proceeds to step S22.
Next, in step S22, it is determined that the person matches the person requiring caution in step S19, or in step S21, it is determined that the count value exceeds the set range. 32, etc., to send an alert signal.

Next, with reference to FIG. 9, processing after the human behavior monitoring unit 22 detects a person acting suspiciously in step S11 of FIG. 8 will be described.
That is, in step S31, since it was determined in step S11 of FIG. 8 that there was a person acting suspiciously, the face authentication determination unit 23 determined whether face authentication was possible for the face image of the person determined to be suspicious. determine whether Here, if it is determined that it can be used for face authentication, the process proceeds to step S32. On the other hand, if it is determined that the face authentication cannot be used, the process proceeds to step S36.

Next, in step S32, since it is determined in step S31 that the acquired image can be used for face authentication, the face authentication section 27 and person matching section 28 carry out face authentication and person matching processing.
Next, in step S<b>33 , the determination unit 29 determines whether or not the person whose face has been authenticated in step S<b>33 matches the person requiring caution stored in the face image DB 31 . Here, if they match, the process proceeds to step S35. On the other hand, if it does not match the person requiring caution, the process proceeds to step S34.

Next, in step S34, although it was determined in step S33 that the person does not match the person requiring caution, the human behavior monitoring unit 22 detects suspicious behavior of the person in step S11. Therefore, the warning generation unit 30 transmits an alert signal with a face image as a suspicious behavior person to the manager's terminal 32 or the like.
The face image transmitted to the administrator's terminal 32 or the like may be registered as, for example, a suspicious behavior person and added to the face image DB 31 .

Next, in step S35, since it was determined in step S33 that the person was matched with the person requiring caution, the warning generation unit 30 determines that the person registered as the person requiring caution is acting suspiciously, and the administrator terminal 32 etc. to send an alert signal.
Next, in step S36, since it is determined that the acquired image cannot be used for face authentication in step S31, the light source control unit 26 performs lighting control of the LED 13 (light guide plate 12 display control) (display step).

Next, in step S37, the face authentication availability determination unit 23 determines whether or not the image acquired by the image acquisition unit 21 after lighting control of the LED 13 in step S36 can be used for face authentication. Here, if it is determined that it can be used for face authentication, the process proceeds to step S38. On the other hand, if it is determined that the face authentication cannot be used, the process proceeds to step S41.
Next, in step S38, since it was determined in step S37 that the acquired image can be used for face authentication, the face authentication section 27 and the person matching section 28 carry out face authentication and person matching processing.

Next, in step S<b>39 , the determination unit 29 determines whether or not the person whose face has been authenticated in step S<b>38 matches the person requiring caution stored in the face image DB 31 . Here, if they match, the process proceeds to step S43. On the other hand, if it does not match the person requiring caution, the process proceeds to step S40.
Next, in step S40, although it was determined in step S39 that the person does not match the person requiring caution, the human behavior monitoring unit 22 detects suspicious behavior of the person in step S11. Therefore, the warning generation unit 30 transmits an alert signal with a face image as a suspicious behavior person to the manager's terminal 32 or the like.

The face image transmitted to the administrator's terminal 32 or the like may be registered as, for example, a suspicious behavior person and added to the face image DB 31 .
In step S39, the person determined by the determination unit 29 not to be a caution-requiring person is displayed on the light guide plate 12 as a result of the display on the light guide plate 12, and the image suitable for face recognition is used for face recognition/personality recognition. Matching is taking place. Therefore, the facial image acquisition system 10 of the present embodiment can highly accurately derive the result that a person who is not a person requiring caution is acting suspiciously.

Next, in step S41, the face authentication disapproval counting unit 24 counts the number of times the face authentication is judged to be disallowed in step S37.
Next, in step S42, the count determination unit 25 determines whether or not the count value obtained by counting the number of times the facial authentication is determined to be unsuccessful in step S41 is less than a predetermined set value. Here, if it is determined that the count value is less than the predetermined set value, the process returns to step S36 to control lighting of the LED 13 with a different lighting pattern.

On the other hand, if it is determined that the count value is equal to or greater than the predetermined set value, the process proceeds to step S43.
Next, in step S43, it is determined that the person matches the caution-requiring person in step S39, or it is determined that the count value exceeds the set value in step S42. Although it was not possible, the alert signal is transmitted to the manager's terminal 32 or the like, assuming that the person is suspicious.

<Main features>
The facial image acquisition system 10 of this embodiment includes a camera 11 , a light guide plate 12 , an LED 13 and a control device 20 . The camera 11 is installed to photograph a person and takes an image of a predetermined imaging range. The light guide plate 12 is provided at a position adjacent to the imaging side of the camera 11, and internally reflects light incident from a predetermined direction to a second surface 12b opposite to the first surface 12b facing the camera 11. It emits light from the surface 12c to perform desired display and has light transmittance. The LEDs 13 allow light to enter the light guide plate 12 from a predetermined direction. The control device 20 transmits a pulse signal for repeating turning on and off at predetermined intervals to the LED 13, and controls the LED 13 so that light is emitted from the LED 13 according to the pulse signal.

As a result, light is emitted from the LED 13 so as to be repeatedly turned on and off in a time division manner, so that a desired display is displayed on the light guide plate 12 according to a predetermined pulse signal to a person within the photographing range of the camera 11. It can be carried out. Therefore, it is possible to attract the attention of a target person (for example, a suspicious person, a person to be watched over, a person to be marketed, etc.) and make the person turn around toward the light guide plate 12 .

In addition, by causing the display unit to perform a specific display based on the pulse signal, for example, by acquiring an image with the camera 11 at a timing when the light is not emitted from the LED 13, the influence of the light from the LED 13 can be avoided. You can get a clearer image without
Therefore, by the camera 11 arranged adjacent to the first surface 12b side of the light guide plate 12, it is possible to photograph the face of the target person substantially from the front and obtain an image with reduced influence of light. Appropriate facial images used for authentication and attribute determination can be obtained.

Furthermore, the target person looking at the light guide plate 12 can visually recognize the camera 11 arranged adjacent to the back side (first surface 12b) of the light guide plate 12 when the specific display is displayed on the light guide plate 12. is difficult.
As a result, it is possible to obtain an image necessary for performing face authentication with higher accuracy than in the past.

[Other embodiments]
Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the invention.

(A)
In the above embodiment, the face image acquisition system and the control method of the face image acquisition system have been described with examples in which the present invention is realized. However, the present invention is not limited to this.
For example, the present invention may be implemented as a control program that causes a computer to execute the control method of the face image acquisition system described above.
This control program is stored in a memory (storage unit) installed in the face image acquisition system, and the CPU reads the control program stored in the memory and causes the hardware to execute each step. More specifically, when the CPU reads the control program and executes the above-described image acquisition step and display step, the same effect as described above can be obtained.
Also, the present invention may be implemented as a recording medium storing a control program for a face image acquisition system.

(B)
In the above embodiment, as shown in FIG. 2 and the like, the light guide plate 12 is arranged at a position adjacent to the photographing side of the camera 11, and the LEDs 13 are directed to the light guide plate 12 according to the information photographed by the camera 11. An example of irradiating light from the above has been described. However, the present invention is not limited to this.

For example, as shown in FIG. 10, a flashlight (second light source) 14 and a speaker (sound information output section) 15 are arranged on the rear (first surface) side of the light guide plate 12 and near the camera 11. It may be a configuration of a face image acquisition system configured as described above.
In this case, in addition to the pattern displayed on the light guide plate 12, the flash light emitted from the flash light 14 is used to attract the attention of a person in the photographing range of the camera 11, so that the direction of the camera 11 can be changed. A face image of the target person can be acquired in a facing state.

In addition to the pattern displayed on the light guide plate 12, the sound information emitted from the speaker 15 is used to attract the attention of a person in the photographing range of the camera 11, so that the person facing the direction of the camera 11 can see the image. A face image of a subject can be acquired.
That is, as means for attracting the attention of a person in the shooting range, in addition to the display on the light guide plate 12, flash light from the flash light 14, sound from the speaker 15, or other means can be used in combination.

(C)
In the above embodiment, by switching the presence/absence of display on the light guide plate 12 (lighting/unlit of the LED 13), the camera 11 arranged adjacent to the back side of the light guide plate 12 can be made visible or invisible from the shooting side. An example of control has been given and explained. However, the present invention is not limited to this.

For example, as shown in FIG. 11, a smoke plate 16 may be installed between the camera 11 and the light guide plate 12 .
In this case, the smoke plate 16 makes it difficult to see the camera 11 at all times regardless of the presence or absence of display on the light guide plate 12 (lighting/lighting of the LED 13).
Therefore, people in the photographing range of the camera 11 can acquire a face image without noticing the presence of the camera 11 and without feeling uncomfortable.

(D)
In the above-described embodiment, an example in which the fine prisms 12d are formed in a predetermined pattern on the inner surface side of the first surface 12b of the light guide plate 12 arranged to face the camera 11 has been described. However, the present invention is not limited to this.
For example, as shown in FIG. 12, a light guide plate 12 having no fine prisms 12d may be provided at a position facing the lens portion of the camera 11. FIG.
Accordingly, the image captured by the camera 11 can be a high-definition image without being affected by the fine prism 12d.

(E)
In the above embodiment, according to the image captured by the camera 11 installed on the wall surface, ceiling, etc. of the facility, the light from the LED 13 is incident on the light guide plate 12 arranged adjacent to the image capturing side of the camera 11. An example of displaying a pattern or the like on the light guide plate 12 has been described. However, the present invention is not limited to this.
For example, a configuration in which a light guide plate is installed as a display installed near a specific product in a department store, etc., and a camera is installed on the back side of the light guide plate may be employed.
In this case, by switching the content to be displayed on the light guide plate according to the attributes of the person who is interested in the specific product and stops, it is possible to display an effective advertisement or the like.

(F)
In the above-described embodiment, as the pattern to be displayed on the light guide plate 12, as shown in FIG. I explained with an example that attracts the interest of people living in However, the present invention is not limited to this.
For example, the pattern to be displayed on the light guide plate is not limited to the weather forecast, and may be an advertisement, design, image, or the like that easily attracts people's interest.

(G)
In the above embodiment, when light is incident on the light guide plate 12 from the LEDs 13, a pattern or the like is displayed on the light guide plate 12, thereby making the camera 11 arranged adjacent to the back side of the light guide plate 12 invisible. explained. However, the present invention is not limited to this.
For example, in a state in which a pattern or the like is displayed on the light guide plate, the camera may not be completely invisible, but may be visible to the extent that it cannot be determined whether it is a camera.

(H)
In the above-described embodiment, the control device 20 turns off the LED 13 according to the determination result of the human behavior monitoring unit 22 to turn off the LED 13 so that the light guide plate 12 does not display a pattern or the like. An example of performing control for switching to the second mode in which patterns and the like are displayed on 12 has been described. However, the present invention is not limited to this.

For example, regardless of the action of a person in the photographing range of the camera, a first mode in which the LED 13 is extinguished and no pattern is displayed on the light guide plate 12 every time a predetermined time elapses, and a light is emitted from the LED 13 to light the light guide plate. 12 may be controlled to switch to a second mode in which a pattern or the like is displayed.
Alternatively, when the number of people in the photographing range of the camera is detected and the number of people exceeds a predetermined number, a first mode in which the LED 13 is turned off and no pattern or the like is displayed on the light guide plate 12, and light is emitted from the LED 13. It is also possible to perform control for switching to the second mode in which a pattern or the like is displayed on the light guide plate 12 by pressing the second mode.

INDUSTRIAL APPLICABILITY The face image acquisition system of the present invention can acquire camera images necessary for performing face recognition with higher accuracy than before. , hotels, office buildings, and other facilities.

10 face image acquisition system 11 camera 12 light guide plate 12a end surface (incidence surface)
12b First surface 12c Second surface (outgoing surface)
12d fine prism 13 LED (first light source unit)
14 flashlight (second light source)
15 speaker (sound information output unit)
16 smoke plate 20 control device (control unit)
21 image acquisition unit 22 human behavior monitoring unit 23 face authentication availability determination unit 24 face authentication failure count unit 25 count determination unit 26 light source control unit 27 face authentication unit 28 person matching unit 29 determination unit 30 warning generation unit (alarm unit)
31 face image DB (storage unit)
32 Administrator terminal 33 Terminal device 40 Management information bus P1 Person

Claims (22)

a camera that is installed to photograph a person and performs imaging in a predetermined imaging range;
It is provided at a position adjacent to the imaging side of the camera, and internally reflects light incident from a predetermined direction so that the light is emitted from the second surface opposite to the first surface facing the camera. A light guide plate that displays and has light transparency,
a first light source unit that causes light to enter the light guide plate from the predetermined direction;
A pulse signal for repeating turning on and off at a predetermined interval is transmitted to the first light source unit, and the first light source unit is controlled to irradiate light from the first light source unit according to the pulse signal. a control unit that
A facial image acquisition system comprising a further comprising an image acquisition unit that acquires an image from the camera at a timing when the light emitted from the first light source unit is turned off;
The facial image acquisition system according to claim 1. When the light emitted from the first light source unit is incident on the light guide plate, the light guide plate displays a pattern that attracts people's attention when viewed from the second surface.
The facial image acquisition system according to claim 1 or 2. When the light emitted from the first light source unit is incident on the light guide plate, the light guide plate performs display such that the camera cannot be viewed from the second surface.
The facial image acquisition system according to any one of claims 1 to 3. The light guide plate is such that the camera can be visually recognized when viewed from the second surface in a state where the light emitted from the first light source unit is not incident.
The facial image acquisition system according to any one of claims 1 to 4. A smoke plate is provided between the light guide plate and the camera, and makes the camera invisible when viewed from the two side sides of the light guide plate.
The facial image acquisition system according to any one of claims 1 to 4. The control unit has a first mode for turning off the first light source unit and a second mode for turning on the first light source unit.
The facial image acquisition system according to any one of claims 1 to 6. The control unit selects the second mode and irradiates light from the first light source unit to the light guide plate when the image obtained from the camera includes a person who seems to be a predetermined target person. ,
The facial image acquisition system according to claim 7. A human behavior monitoring unit that monitors the behavior of a person within the imaging range of the camera and determines whether the person is a person to be monitored.
The facial image acquisition system according to any one of claims 1 to 8. The control unit controls the first light source unit so as to perform a specific display according to the attributes of the person looking in the direction of the camera.
The facial image acquisition system according to any one of claims 1 to 9. said specific displays include advertisements, information of interest to said person;
The facial image acquisition system according to claim 10. further comprising a second light source unit arranged on the first surface side of the light guide plate and emitting flash light to turn the person around;
The facial image acquisition system according to any one of claims 1 to 11. The lens of the camera is arranged so as to be adjacent to an area provided on the first surface of the light guide plate and not provided with light-reflecting microprisms.
The facial image acquisition system according to any one of claims 1 to 12. The control unit switches the direction of light incident on the light guide plate, and controls to switch the plurality of patterns displayed on the light guide plate.
The facial image acquisition system according to any one of claims 1 to 13. Inside the light guide plate, fine prisms corresponding to the plurality of patterns are arranged in a plurality of patterns in a state in which a person's face can be recognized from the camera through the light guide plate.
15. The facial image acquisition system according to claim 14. further comprising a sound output unit that outputs sound information in accordance with display content displayed on the light guide plate;
The facial image acquisition system according to any one of claims 1 to 15. Further comprising a face authentication availability determination unit that determines whether the face authentication of the person imaged by the camera is equal to or greater than a predetermined determination value,
The facial image acquisition system according to any one of claims 1 to 16. The control unit counts the number of times that the determination result in the face authentication propriety determination unit is rejected, and switches the display of the light guide plate until the count exceeds a predetermined number of times. to control the
18. The facial image acquisition system according to claim 17. a storage unit that stores a face image of a specific person in advance;
a person matching unit for matching a face image of a person captured by the camera with a face image of the specific person stored in the storage unit when the determination result in the face authentication propriety determination unit is equal to or greater than the determination value; , further comprising
19. The facial image acquisition system according to claim 18. an alarm unit that issues an alarm when it is determined that the face image of the person captured by the camera matches a face image of a specific person that has been stored in advance as a result of collation by the person collation unit; ing,
20. The facial image acquisition system according to claim 19. A control method for a facial image acquisition system according to any one of claims 1 to 20,
an image acquisition step of acquiring an image obtained by capturing the predetermined imaging range from the camera;
A pulse signal for repeating lighting and extinguishing at a predetermined interval is transmitted to the first light source unit, light is emitted from the first light source unit according to the pulse signal, and the second surface of the light guide plate a display step of performing desired display when viewed from the side;
A method of controlling a facial image acquisition system with A control program for controlling the facial image acquisition system according to any one of claims 1 to 20,
an image acquisition step of acquiring an image obtained by capturing the predetermined imaging range from the camera;
A pulse signal for repeating lighting and extinguishing at a predetermined interval is transmitted to the first light source unit, light is emitted from the first light source unit according to the pulse signal, and the second surface of the light guide plate a display step of performing desired display when viewed from the side;
A control program that causes a computer to execute a control method of a face image acquisition system equipped with

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