JP7323667B2 - Terahertz wave detection device, terahertz wave detection method, and information processing device - Google Patents

Description

The present invention relates to a terahertz wave detection device, a terahertz wave detection method, and an information processing device.

Various VCO gases are known to exhibit characteristic frequency absorption spectra in the region of terahertz waves (0.1 THz to 10 THz, hereinafter referred to as "THz waves"). It is also known that THz waves have longer wavelengths than infrared light and are less susceptible to aerosols. Therefore, Non-Patent Document 1 discloses research on applying THz waves to analysis of VCO gas using the properties of THz waves.

Gapless THz Comb Spectroscopy (Laser Research, Vol. 42, No. 9, pp. 1-6, September 2014)

Non-Patent Document 1 mentions generating a terahertz wave without an interspectral gap, but does not present the display of the results of analysis performed with a THz wave. Terahertz waves have longer wavelengths than light, and imaging received waves of terahertz waves does not provide the same resolution as visible light images. There is room for improvement.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a display technique that facilitates viewing of analysis results using terahertz waves.

In order to solve the above problems, the present invention provides a transmitter that transmits terahertz waves, and a receiver that receives reflected terahertz waves reflected by a reflector existing behind an object irradiated with the terahertz waves. a terahertz wave transceiver, a camera, a display, and an information processing device comprising the terahertz wave transceiver, the camera, and the display, wherein the transmitter sweeps frequencies including a specific frequency The information processing device performs analysis processing for analyzing the received terahertz waves, and based on the analysis results of the analysis processing, the image captured by the camera is converted to the analysis results. a display image generation process for generating a display image for superimposing an image based on the display, and displaying the display image on the display; a distance calculation process for detecting a frequency difference from the frequency of the received terahertz wave and calculating a distance from the terahertz wave transceiver to the reflecting object based on the frequency difference; an object identification process for identifying the type of the object, the intensity of the terahertz wave emitted from the transmitter, the attenuation of the received terahertz wave with respect to the terahertz wave emitted from the transmitter, and the distance and a distribution calculation process for calculating a variation in the spread of the distribution of the object based on, and in the display image generation process, the spread of the distribution is calculated according to the background of the image captured by the camera. A display image is generated according to the amount of change in the background image, and the display image is superimposed on the background image and displayed on the display.

ADVANTAGE OF THE INVENTION According to this invention, the display technique which makes it easy to see the analysis result using a terahertz wave can be provided. Objects, configurations, and effects other than those described above will be clarified in the following embodiments.

Front view of the THz wave detection device according to the first embodiment Side cross-sectional view of the THz wave detection device according to the first embodiment Hardware configuration diagram of the THz wave detection device according to the first embodiment Functional block diagram of the THz wave detection device according to the first embodiment Diagram for explaining transmission and reception signals of THz waves A diagram showing the signal strength of the received signal Flowchart showing the operation flow of the THz wave detection device Diagram explaining gas visualization method Diagram showing an example of image composition processing Diagram showing an example of image composition processing External view of the THz wave detection device according to the second embodiment Controller functional block diagram The figure which shows the application example of the THz wave detection apparatus by 2nd embodiment. A diagram showing the relationship of the distance between the THz wave detector and the gas to be analyzed. A diagram showing the relationship of the distance between the THz wave detector and the gas to be analyzed. Flowchart showing the processing flow of the THz wave detection device according to the third embodiment, particularly the gas visualization application unit A diagram for explaining the feature value representing the temporal change in the distribution of the concentration of the gas to be analyzed. A diagram showing an example of a concentration distribution map Diagram showing composite image Flowchart showing the processing flow of the gas visualization application unit according to the fourth embodiment Front view of the THz wave detector according to the fifth embodiment Side sectional view of the THz wave detection device according to the fifth embodiment Flowchart showing the processing flow of the gas visualization application unit in the fifth embodiment

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same configurations and processing steps are denoted by the same reference numerals, and redundant description is omitted.

[First embodiment]
The first embodiment describes an example in which the THz wave detection device 100 is applied to a gas visualization device. FIG. 1A is a front view of the THz wave detection device according to the first embodiment. FIG. 1B is a side sectional view of the THz wave detection device according to the first embodiment. FIG. 2 is a hardware configuration diagram of the THz wave detection device according to the first embodiment.

A THz wave detection device 100 shown in FIG. 1A is configured by externally attaching a THz wave transmitter/receiver 1 to a smart phone 10 as an information processing device. The information processing device may be another portable information terminal such as a tablet terminal. The THz wave detector 100 may be configured by connecting the THz wave transmitter/receiver 1 to a computer.

As shown in FIG. 1B , the smartphone 10 has an extension I/F 125 to which the THz wave transmitter/receiver 1 is connected.

The smartphone 10 has a display 141 and a front camera 143 on the front. Further, the smartphone 10 has a rear camera 144 on its rear surface. The smartphone 10 also houses the processor 107 inside the housing.

FIG. 2 is a block diagram showing an example of the internal configuration of the smartphone 10. As shown in FIG. 2, the smartphone 10 includes a CPU (Central Processing Unit) 101, a system bus 102, a ROM (Read Only Memory) 103, a RAM (Random Access Memory) 104, a storage 110, a communication processor 120, an expansion interface 125, an operation device 130 , a video processor 140 , an audio processor 150 and a sensor 160 .

The CPU 101 is a microprocessor unit that controls the smartphone 10 as a whole. A system bus 102 is a data communication path for transmitting and receiving data between the CPU 101 and each operation block in the smartphone 10 .

A ROM 103 is a memory storing a basic operation program such as an operating system and other operation programs.
Programmable Read Only Memory) and rewritable ROM such as flash ROM are used. The RAM 104 serves as a work area for executing the basic operating program and other operating programs. The ROM 103 and RAM 104 may be integrated with the CPU 101 . Also, the ROM 103 may use a partial storage area in the storage 110 instead of having an independent configuration as shown in FIG. The processor 107 is configured by connecting a CPU 101 , a ROM 103 , a RAM 104 and a storage 110 via a system bus 102 .

The storage 110 stores an operation program and operation setting values of the smartphone 10, images captured by the smartphone 10, user information of the smartphone 10, and the like.

All or part of the functions of the ROM 103 may be replaced by a partial area of the storage 110 . In addition, the storage 110 needs to retain stored information even when power is not supplied to the smartphone 10 from the outside. Therefore, devices such as flash ROMs, SSDs (Solid State Drives), and HDDs (Hard Disk Drives) are used.

It should be noted that each operation program stored in the ROM 103 and the storage 110 can be updated and expanded in function by downloading from each server device (not shown) on a wide area public network.

The communication processor 120 includes a LAN (Local Area Network) communication device 121 , a telephone network communication device 122 , an NFC (Near Field Communication) communication device 123 and a Bluetooth (registered trademark) communication device 124 . The LAN communication device 121 is connected to a wide area public network via an access point (AP) device (not shown) by wireless connection such as Wi-Fi (registered trademark), and transmits and receives data to and from each server device on the wide area public network. I do. The telephone network communication device 122 performs telephone communication (phone call) and data transmission/reception by wireless communication with a base station (not shown) of the mobile telephone communication network. The NFC communication device 123 performs wireless communication when in close proximity to a corresponding reader/writer. The Bluetooth communication device 124 transmits and receives data to and from corresponding terminals by wireless communication. The LAN communication device 121, the telephone network communication device 122, the NFC communication device 123, and the Bluetooth communication device 124 are each provided with an encoding circuit, a decoding circuit, an antenna, and the like. Also, the communication processor 120 may further include infrared communication or other communication devices.

The expansion interface 125 is a group of interfaces for expanding the functions of the smart phone 10, and in this embodiment, it is assumed to be composed of a video/audio interface, a USB (Universal Serial Bus) interface, a memory interface, and the like. The video/audio interface inputs video/audio signals from an external video/audio output device, outputs video/audio signals to an external video/audio input device, and the like. The USB interface is connected to a PC (Personal Computer) or the like to transmit and receive data. Also, a keyboard or other USB devices may be connected. A memory interface connects a memory card or other memory medium to transmit and receive data.

The operation device 130 is an instruction input device for inputting an operation instruction to the smartphone 10, and in this embodiment, it is configured with a touch panel arranged over the display 141 and operation keys arranged with button switches. Only one of them may be used, or the smartphone 10 may be operated using a keyboard or the like connected to the extended interface 125 . Alternatively, the smartphone 10 may be operated using a separate portable terminal device connected by wired communication or wireless communication. Also, the touch panel function may be provided by the display 141 .

The video processor 140 is composed of a display 141 , an image signal processor 142 , a front camera 143 and a rear camera 144 . The front camera 143 is a camera arranged on the same side (front) as the display 141, and is used for so-called self-portrait, in which the user confirms his or her face captured by the front camera 143 on the display 141 and captures the image. The rear camera 144 is a camera arranged on the opposite side (back) of the display 141 .

The display 141 is a display device such as a liquid crystal panel, for example, and displays image data processed by the image signal processor 142 to provide the user of the smartphone 10 with the image data. The image signal processor 142 includes a video RAM (not shown), and drives the display 141 based on image data input to the video RAM. Also, the image signal processor 142 has a function of performing format conversion, superimposition processing of menus and other OSD (On-Screen Display) signals, etc., as necessary. The front camera 143 and the rear camera 144 use electronic devices such as CCD (Charge-Coupled Device) and CMOS (Complementary Metal Oxide Semiconductor) sensors to convert the light input from the lens into electrical signals, thereby capturing the surroundings and objects. It is a camera unit that functions as an imaging device for inputting image data of

Audio processor 150 includes speaker 151 , audio signal processor 152 and microphone 153 . The speaker 151 provides the user of the smart phone 10 with the audio signal processed by the audio signal processor 152 . A microphone 153 converts a user's voice or the like into voice data and inputs the voice data.

The sensor 160 is a sensor group for detecting the state of the smartphone 10. In this embodiment, a GPS (Global Positioning System) receiver 161, a gyro sensor 162, a geomagnetic sensor 163, an acceleration sensor 164, an illuminance sensor 165, a human It includes a sensitive sensor 166 . These sensors make it possible to detect the position, tilt, direction, movement, ambient brightness, etc. of the smartphone 10 . Also, the smartphone 10 may further include a pressure sensor or other sensors such as an air pressure sensor. The location information is acquired by the GPS receiver 161, but if it cannot be acquired in a location where it is difficult to receive GPS radio waves, the LAN communication device 121 can be used to acquire the location information from the Wi-Fi AP device. Alternatively, it may be obtained from the base station information by the telephone network communication device 122 .

Note that the configuration example of the smartphone 10 shown in FIG. 2 includes many components such as the communication processor 120 that are not essential to the present embodiment. without losing its effectiveness. In addition, a configuration (not shown) such as a digital broadcast receiving function and an electronic money settlement function may be added.

FIG. 3 is a functional block diagram of the THz wave detection device 100 according to the first embodiment. The THz wave detector 100 is configured by connecting the THz wave transmitter/receiver 1 and the rear camera 144 to the input stage of the processor 107 and connecting the display 141 to the output stage of the processor 107 .

Processor 107 mainly includes analysis unit 2 and visualization unit 4 . The analysis unit 2 and the visualization unit 4 are configured by executing software that implements the functions of the THz wave detection device 100 using hardware that configures the processor 107 .

A THz wave transceiver includes a transmitter 11 , a receiver 12 , a transmission controller 13 and an antenna 14 .

The THz wave transmitter/receiver 1 irradiates a transmission wave 15 a from an antenna 14 attached to the THz wave transmitter/receiver 1 toward a three-dimensional space containing the gas 6 to be analyzed. The gas to be analyzed 6 absorbs a specific frequency spectrum. Then, the antenna 14 receives the reflected terahertz wave 15 b that has passed through the analysis target gas 6 and is reflected by the background reflector 5 .

The transmission control unit 13 controls the transmitter 11 so that the transmitter 11 outputs a THz wave (transmission signal) obtained by sweeping the frequency of the spectrum. The transmitter 11 converts the transmission signal into a transmission wave 15 a (THz wave), and irradiates the two-dimensional region including the analysis target gas 6 from the antenna 14 . The receiver 12 acquires the reflected terahertz wave 15 b received by the antenna 14 , converts it into a received signal, and sends it to the analysis unit 2 .

Irradiation of the transmission wave 15a to the two-dimensional region is performed by scanning the irradiation direction horizontally or vertically for each unit, with the period for sweeping the frequency of the spectrum as one unit. The irradiation direction scanning means may be mechanical means using a galvanomirror or the like, or may be a phased array antenna in which a plurality of antenna elements are arranged in an array, and a THz wave input to each antenna element. Electrical means for differentiating the phases of the signals may also be used. A scanning synchronization signal is shared with the visualization unit 4 .

The analysis unit 2 includes a frequency difference detector 21, a wave detector 22, a frequency detector 23, a reflection distance calculator 24, a reference intensity detector 25, an attenuation amount detector 26, a normalized concentration calculator 27, and an attenuation ratio calculator 28. , including the gas identifier 29 .

On the other hand, the visualization unit 4 includes a depth image generation unit 41 , a density image generation unit 42 , a graphic image generation unit 43 and an image synthesis unit 44 .

The frequency difference detector 21 obtains the frequency difference Δf0 between the transmission signal and the reception signal from the interference signal between the transmission signal and the reception signal, and outputs it to the reflection distance calculator 24 .

The reflection distance calculation unit 24 calculates the reflection distance d between the antenna 14 and the background reflector 5 from Δf0, and outputs the reflection distance d to the normalized density calculation unit 27 and the depth image generation unit 41, respectively.

The detector 22 detects the envelope of the received signal and outputs it to the reference intensity detector 25 and the attenuation detector 26, respectively.

The reference intensity detector 25 detects the reference intensity R in a frequency range where the analysis target gas 6 does not spectrally absorb THz waves, based on the envelope of the received signal. The reference strength detector 25 outputs the reference strength R to the damping ratio calculator 28 .

Based on the envelope of the received signal, the attenuation detection unit 26 detects the depression of the envelope at a specific frequency where the gas 6 to be analyzed is spectrally absorbed, and detects the attenuation S from the depression. The attenuation amount detection unit 26 outputs the attenuation amount S to the attenuation ratio calculation unit 28 .

The attenuation amount detection unit 26 also outputs the timing of depression to the frequency detector 23 . The frequency detector 23 detects the frequency f<b>1 of the reception signal at which the depression occurs, and outputs the frequency f<b>1 to the gas identification unit 29 .

The gas identification unit 29 identifies the type of gas whose absorption spectrum frequency is f1 and outputs it to the graphic image generation unit 43 .

The attenuation ratio calculator 28 calculates the attenuation ratio R/S from the reference intensity R and the attenuation amount S, and outputs it to the normalized concentration calculator 27 .

A normalized density calculator 27 calculates a normalized density R/S/d by dividing the attenuation ratio R/S by the reflection distance d. The normalized density calculator 27 outputs the normalized density R/S/d to the density image generator 42 .

The rear camera 144 includes an imaging section 1441 and a camera control section 1442 . The imaging unit 1441 includes, for example, an imaging device such as a CMOS sensor and an imaging lens. The imaging unit 1441 captures a visible light or infrared light image of a two-dimensional area irradiated with THz waves. A camera control unit 1442 converts the signal from the imaging unit 1441 into an RGB signal. A part of the imaging region may correspond to the irradiation region of the THz wave signal. The front camera 143 includes an imaging unit 1431 and a camera control unit 1432, similar to the rear camera 144. FIG. An embodiment using the front camera 143 will be described in the third embodiment.

The depth image generation unit 41 receives the reflection distance d, and generates a two-dimensional image by converting the reflection distance d into monochromatic intensity in synchronization with irradiation scanning of THz waves.

The density image generator 42 receives the normalized densities R/S/d, and converts the normalized densities R/S/d into a single color intensity or a predetermined color in synchronization with irradiation scanning synchronization of THz waves. to generate a two-dimensional image.

The graphic image generator 43 obtains text data as the gas type information, and further converts the text data into graphic image data to obtain a graphic image.

The image synthesizing unit 44 receives a depth image, a density image, a graphic image, and a camera image, synthesizes these images, and outputs the synthesized image to the display 141 .

FIG. 4 is a diagram for explaining a gas and odor analysis method. It mainly relates to the THz wave transmitter/receiver 1 and the analysis unit 2 in FIG.

FIG. 4A is a diagram for explaining a THz wave transmission signal 201 and a reception signal 202. The transmission wave 15a and the reflected terahertz wave 15b are inside and outside the antenna 14, respectively. FIG. 4A shows the transmitted signal 201 and received signal 202 against the three axes of time, signal strength and frequency.

A transmission signal 201 indicated by a dashed line performs a sweep operation in which the frequency is gradually changed in the THz wave region while the signal strength is kept constant in unit time Tm. The frequency range of the sweep is B. After completing one unit of sweep, the transmission signal 201 performs the next sweep operation, but the irradiation location differs according to the irradiation scanning described above.

A received signal 202 indicated by a solid line is slightly delayed with respect to the transmitted signal 201 . This is due to the round trip of the reflection distance d. Due to this delay, there is a frequency difference Δf0 between the transmission signal 201 and the reception signal 202 when observed at the same time. Also, the signal strength of the received signal 202 dips at a specific frequency f1. This is because the analysis target gas 6 performs spectral absorption at the frequency f1.

FIG. 4B is a diagram showing the signal strength of the received signal 202. As shown in FIG. As explained in FIG. 4B, there is a dip at frequency f1. The reference intensity R is the signal intensity when there is no gas absorption, and can be obtained as the average of a plurality of points sampled from a flat portion avoiding a recessed portion. The signal intensity S of the recessed portion is the signal intensity attenuated by absorption by the gas, and represents the degree of absorption by the gas. The higher the gas concentration, the greater the attenuation and the smaller S. The attenuation rate due to gas absorption is R/S.

The reflection distance calculator 24 calculates the reflection distance d by the following formula (1).

The normalized concentration calculator 27 calculates the normalized gas concentration (also referred to as normalized concentration) by the following equation (2).

FIG. 5 is a flow chart showing the operation flow of the THz wave detection device 100. As shown in FIG.

When the THz wave detection device 100 is activated, initial setting is performed (S10). The THz wave detection device 100 performs imaging processing (S11) by the rear camera 144 and measurement by the THz wave transmitter/receiver 1, i.e., THz wave irradiation toward the analysis target (in this embodiment, the area where the analysis target gas is present). A series of processes of control (S12), THz wave irradiation (S13), and reflected terahertz wave reception (S14) are executed in parallel. S12 to S14 are a THz wave control process S1, and control for irradiating the target region with THz waves is performed in S12. For example, the irradiation level of the THz wave, the sweep time unit, the frequency width, and the like. In S13, the irradiation of the THz wave is executed and instructed, and in S14, the detection signal of the received signal, which is the reflected terahertz wave, is obtained.

After receiving the reflected terahertz wave (S14), frequency difference detection processing by the frequency difference detector 21 (S15), reference strength detection processing by the reference strength detection unit 25 (S16), attenuation strength detection processing by the attenuation amount detection unit 26 (S17). , and frequency detection processing by the frequency detector 23 (S18). S15 to S25 constitute analysis process S2.

After the frequency difference detection process (S15), the reflection distance d is calculated by the reflection distance calculator 24 (S19) and recorded in the RAM 104 or storage 110 (S23). Then, the reflection distance calculator 24 outputs the reflection distance d to the depth image generator 41, and the depth image generator 41 generates the depth image 51 (see FIG. 6) (S26).

After the reference intensity detection process (S16), the gas attenuation rate R/S calculation process is performed by the attenuation ratio calculation unit 28 (S20). Next, a normalized density calculation process (S21) is executed by the normalized density calculation unit 27, and recorded in the RAM 104 or the storage 110 (S24). Then, the normalized density calculator 27 outputs the normalized density R/S/d to the density image generator 42, and the density image generator 42 generates the density image 52 (see FIG. 6) (S27).

After the attenuation intensity detection process (S17), the frequency detector 23 detects the depressed (attenuated) frequency f1 (S18), and the gas identification unit 29 identifies the type of gas based on the frequency f1, that is, the component of the gas. is identified (S22) and recorded in the RAM 104 or storage 110 (S25). Then, the gas identification unit 29 outputs the component identification result as text data to the graphic image generation unit 43, and the graphic image generation unit 43 generates the graphic image 53 (see FIG. 6) (S28).

The rear camera 144 captures a background image (S11) and acquires a camera image (S29).

The image synthesizing unit 44 acquires the depth image 51, the density image 52, the graphic image 53, and the camera image 54, synthesizes these four images (S30), and displays them on the display 141 (S31).

The CPU 101 determines whether or not the repetition is necessary (S32), and determines whether the repetition is necessary (S32/Yes) S11, S12. back to If it is determined that repetition is unnecessary (S32/No), the process ends.

FIG. 6 is a diagram illustrating a gas visualization method.

The depth image 51 is a two-dimensional image obtained by, for example, converting the reflection distance d into a monochromatic intensity in synchronization with irradiation scanning of THz waves. The depth image 51 has a THz wave with a longer wavelength than visible light, and is inferior in definition to a camera image captured with visible light. The depth image 51 visualizes the reflection distance d to the background reflection object, and it is possible to observe the background covered with aerosol or the like. For this reason, it is useful for recognizing obstacles, emergency exits, and the like during evacuation in combination with the camera image 54 . Note that the relationship between the range in which the THz wave is scanned two-dimensionally and the angle of view of the camera image is detected and stored in advance for the corresponding range.

Similarly, the gas concentration image 52 is two-dimensionally imaged by converting the normalized concentration R/S/d into a monochromatic intensity or color mapping in synchronization with the THz wave irradiation scanning synchronization. is. By normalizing the gas concentration R/S with the reflection distance d, the gas hazard can be visualized in terms of concentration and distance.

The graphic image 53 is obtained by converting the text data of the gas type information into graphic image data. In addition to the type of gas, it is also useful as an auxiliary image for visualization, such as a warning message according to the degree of danger or a change in gas over time that is easy to understand.

A camera image 54 is a camera image captured by the rear camera 144 . Since the image is an image of the visible light reflected by the background reflecting object 5, it is called a background image.

The synthesized/display image 55 is an image obtained by synthesizing the depth image 51, the density image 52, the graphic image 53, and the camera image 54, and serves as a display image. The four images form four layer images of the composite image, and alpha blending is used as a method of combining to obtain a composite image that is easy to see. Also, the depth image 51 and the camera image 54 can be used complementarily. When the camera image 54 is unstable in an environment such as an aerosol, it is also possible to display mainly the depth image 51 or replace part of the camera image 54 with the depth image 51 for synthesis. In addition, from the camera image 54 and the depth image 51, the characteristic locations such as the exit door of the camera image 54 and obstacles on the evacuation route may be recognized and displayed.

The image synthesizing unit 44 acquires the depth image 51 , the density image 52 , the graphic image 53 and the camera image 54 . Then, the camera image 54 and the depth image 51 are compared to obtain the subject distance of the camera image 54 . Next, the image synthesizing unit 44 compares the density image 52 and the depth image 51 to determine whether the gas 520 displayed in the density image 52 is in front of or behind the subject of the camera image 54 . In the composite/display image 55 of FIG. 6, when the distance from the THz wave detection device 100 to the chair in the depth image 51 is compared with the distance from the THz wave detection device 100 to the gas 520, the distance from the THz wave detection device 100 to the gas 520 is is short, the gas 520 is superimposed on the chair imaged in the depth image 51 and drawn so that it can be seen in front.

7A and 7B are diagrams showing an example of image composition processing. 7A and 7B, the density image 521 and the camera image 541 are the same image. On the other hand, the depth images 511 and 512 are different. In the depth image 511, the table is located farther than the gas, and in the depth image 512, the table is located closer than the gas. In this case, the image composition unit 44 generates a composite/display image 551 in which gas is drawn in front of the table in FIG. 7A. In addition, the image composition unit 44 generates a composition/display image 552 in which gas is drawn on the back surface of the table in FIG. 7B.

As described above, according to the first embodiment, by displaying the gas concentration image 52 superimposed on the background image of the depth image 51 or the camera image 54, it is possible to determine the position of the gas with respect to the background image. can be visualized. A high-resolution background image can be obtained from the camera image 54, and the background can be confirmed with the depth image 51 in an environment such as an aerosol, and a background image can be obtained in various environments. Furthermore, this embodiment can be used not only for gas analysis, but also for analysis in a place such as a kitchen where foul odors are generated.

[Second embodiment]
A second embodiment will be described with reference to FIGS. 8 to 10 . The second embodiment is an example in which the THz wave transmitter/receiver 1 is attached to the wearable terminal 300 to configure the THz wave detection device 100a. The THz wave transmitter/receiver 1 may be integrated with the wearable terminal 300 . A user of the THz wave detection device 100a can use the THz wave detection device 100a with the THz wave detection device 100a attached to the body, and can have both hands free.

FIG. 8 is an external view of a THz wave detection device 100a according to the second embodiment. As shown in FIG. 8, the THz wave detection device 100a is configured by attaching a THz wave transmitter/receiver 1a and a camera 3 to a wearable terminal 300. As shown in FIG.

The wearable terminal 300 includes a parietal holder 303 and a temporal holder 304, a glasses-shaped optical section 302 provided in front of the temporal holder 304, and a screen 305 further provided in front of the glasses-shaped optical section 302. , and an image projector 301 mounted on a crown holder 303 .

The THz wave transmitter/receiver 1a and the camera 3 are attached to the top of the top of the head holder 303, for example.

Further, the THz wave detection device 100a includes a THz wave transmitter/receiver 1a, a camera 3, an image projector 301, a glasses-type optical unit 302, and a controller 7b electrically or communicatively connected to the screen 305. FIG.

The controller 7 is the smartphone 10 from which the functions of the camera 3 and the display are omitted. The screen 305 , image projector 301 , and spectacles-type optical section 302 correspond to the display 141 . Also, the top of head holder 303 and the temporal head holder 304 are used to mount the camera 3, the THz wave transmitter/receiver 1a, and the display on the head of the user of the THz wave detection device 100a.

Image projector 301 projects a composite/display image 55 onto screen 305 . At this time, the depth image 51 can be displayed as a 3D display that gives perspective according to the reflection distance d. For this reason, the composite/display image 55 is composed of an image viewed by the left eye and an image viewed by the right eye. An electronic shutter 102a (see FIG. 9) is incorporated in the spectacles-type optical unit 302, and when projecting a visible image for the left eye, the spectacles-type optical unit 302 makes the left eye side transparent and blocks the right eye side with the electronic shutter. to control the state. When projecting a visual image for the right eye, the spectacles-type optical unit 302 controls the right-eye side to be in a transmission state and the left-eye side to be in a blocked state with an electronic shutter.

The screen 305 may be a transflective screen. In this case, the camera image 54 is not included in the composite/display image 55 . A background image seen through a semi-transmissive screen 305, and a composite/display image 55 composed of at least one of a depth image 51, a density image 52, and a graphic image 53 projected onto the semi-transmissive screen 305 by the image projector 301. view together. The camera image 54 is used for alignment and the like when obtaining the composite/display image 55 . The user can safely use the THz wave detection device 100a while viewing the real image of the background through the transflective screen 305 .

FIG. 9 is a functional configuration diagram of the controller 7. As shown in FIG. The controller 7 includes a CPU 71 , RAM 72 , FROM 73 , SDI/F 74 a , SD memory 74 b , communication I/F 75 , graphic processor 76 , touch panel display 45 a , USB (R) I/F 77 and optical system control section 78 . The USB (R) I/F 77 is connected with the THz wave transmitter/receiver 1a and the camera 3 . The optical system controller 78 is connected to the electronic shutter 102a and controls opening and closing of the electronic shutter 102a.

The THz wave transmitter/receiver 1a has a USB I/F 14 at 14 .

The controller develops a program stored in FROM 73 in RAM 72 and executes it in CPU 71 . The FROM 73 contains a THz wave control process section 731, a camera control process section 732, an analysis process section 733, a visualization process section 734, and a gas visualization application section (abbreviation of application) 735 as programs related to gas and odor analysis and visualization. including. Here, the THz wave control processor 731 is involved in the operation of the THz wave transmitter/receiver 1 shown in FIG. 3, especially the transmission control unit 13 . Camera control processor 732 is involved in the operation of camera controller 1432 or 1442 in front camera 143 or rear camera 144 in FIG. Analysis processor 733 is involved in the operation of analysis unit 2 in FIG. A visualization process unit 734 and a gas visualization application unit 735 correspond to the visualization unit 4 in FIG.

After being activated, the gas visualization application unit 735 controls the user interface, calls the THz wave control process unit 731, the camera control process unit 732, the analysis process unit 733, and the visualization process unit 734, and executes gas and odor analysis and visualization. .

The SD memory 74b stores application data and the like, and exchanges data with the CPU 71 via the SDI/F 74a. The communication I/F 75 is a communication interface such as 3G or 4G mobile communication or wireless LAN, and connects to a server or the like (not shown) via the Internet. The controller 7 may cause the server to execute part of the program to be executed, thereby reducing its own processing load.

The graphic processor 76 generates an image to be displayed on the display screen of the touch panel display 45a from the application data generated by the program. Also, the camera image data obtained by the camera 3 is captured and displayed. In addition to the display screen, the touch panel display 45a has a touch panel as a user input operation section.

A USB I/F 77 is a serial bus interface, and connects the controller 7, the THz wave transmitter/receiver 1a, and the camera 3, respectively.

The THz wave transmitter/receiver 1a is obtained by adding a USB I/F 14 to the THz wave transmitter/receiver 1 according to the first embodiment. Data is transmitted and received between the USB I/F 14 and the USB IF 77 of the controller 7 . At this time, the received signal of the THz wave may not be transmitted and received, for example, the detected envelope may be converted into digital data and transmitted and received.

FIG. 10 is a diagram showing an application example of the THz wave detection device 100a according to the second embodiment. The THz wave detection device 100b of FIG. 10 is different in that the THz wave transmitter/receiver 1 and the camera 3 are integrated into the THz wave detection device 100a or are attached in close contact with the THz wave detection device 100a. The THz wave detection device 100b is the aperture 31a of the camera 3 and the antenna 14a of the THz wave transceiver 1 . The THz wave detection device 100b also incorporates a controller 7a.

The THz wave detection device 100b transmits and receives a communication signal 75a, and is connected to the server device 92 via the Internet 91 via the communication base station 90 for communication.

The server device 92 can execute a part of the program to be executed by the controller 7 to reduce the processing load of the controller 7a. For example, the frequency f1 of the absorption spectrum may be notified to the server device 92, the database in the server device 92 may be used to identify the gas type corresponding to the frequency f1, and the result may be returned to the controller 7a.

Alternatively, the depth image 51 and the camera image 54 may be transmitted to the server device 92 so that the server device 92 recognizes the characteristic portion of the background image.

In addition, in response to an alert issued by the controller 7a, the server device 92 identifies the degree of danger, notifies the police and fire department, and makes the controller 7a present a specific proposal for evacuation instructions. may

As described above, according to the second embodiment, a general-purpose information device can be used to realize a gas and odor visualization device.

[Third Embodiment]
A third embodiment will be described with reference to FIGS. 11A, 11B, and 12. FIG. The third embodiment is particularly characterized by the function of measuring the distance to the gas.

FIG. 11A is a diagram showing the relationship of the distance between the THz wave detector 100b and the analysis target gas 6. FIG.

The telescopic device 80 of FIG. 11A includes a handle 83, an extendable rod 82 attached to one end of the extendable rod 82, and a support base 81 attached to the distal end of the extendable rod 82 (on the side opposite to the handle 83). and The THz wave detection device 100b is fixed to the support base 81. As shown in FIG. The user grips the handle 83 and adjusts the length of the telescopic rod 82 to measure and visualize the analysis target gas 6 with the THz wave detector 100b attached to the support base 81 . The length of the telescopic rod 82 can change the distance between the THz wave detector 100b and the gas 6 to be analyzed. Here, the extended state or contracted state of the telescopic rod 82 is also taken in together with the measurement data.

FIG. 11B shows a diagram showing the relationship of the distance between the THz wave detector 100b and the gas 6 to be analyzed.

At the position P1 of the THz wave detection device 100b, the telescopic rod 82 is in a contracted state, and the angle facing the gas 6 to be analyzed is θ1. On the other hand, at the position P2 of the THz wave detection device 100b, the telescopic rod 82 is in an extended state, the distance to the analysis target gas 6 is shortened by the analysis distance difference l (L), and the angle facing the analysis target gas 6 is θ2 is. At this time, the distance Lg to the gas to be analyzed 6 is given by equation (3).

FIG. 12 is a flow chart showing the processing flow of the THz wave detection device 100b according to the third embodiment, particularly the gas visualization application unit 735. As shown in FIG.

When the gas visualization application unit 735 is activated and initial settings are performed (S10), the THz wave control process (S1) and the analysis process S2 are subsequently executed. At this time, the telescopic rod 82 is in a contracted state, and the first concentration image of the gas 6 to be analyzed is generated (S34).

Next, the user extends the telescopic rod 82 to change the measurement distance (S35), and executes the THz wave control process (S1) and the analysis process S2 again.

Then, the visualization processing unit 734 generates a second concentration image of the analysis target gas 6 (S36).

The analysis processing unit 733 calculates the above equation (3) and obtains the distance Lg to the gas (S37).

Next, the analysis processor 733 recalculates the normalized concentrations R/S/Lg (S38).

The analysis processor 733 performs density recording of the normalized densities R/S/Lg (S24) to obtain a third density image (S39). S34-S38 constitute a first extended process S4 of the analysis process S2.

In addition to the third density image (S39), the visualization processing unit 734 generates the depth image 51 (S26), the graphic image 53 (S28), and the camera image 54 (S29). Then, using the third density image and at least one of the depth image 51, the graphic image 53, and the camera image 54, image synthesis processing (S30) is performed, and a synthesized/display image 55 is displayed (S31). If the repeat condition is satisfied (S32/Yes), a series of processes are repeated, and if the repeat condition is not satisfied (S32/No), the process ends.

As described above, according to the third embodiment, the distance Lg to the gas to be analyzed is used instead of the reflection distance d to the background reflector when normalizing the gas concentration. As a result, the degree of danger represented by the normalized gas concentration becomes more accurate.

[Fourth embodiment]
A fourth embodiment will be described with reference to FIGS. 13A to 15. FIG. FIG. 13A is a diagram for explaining a feature quantity representing a temporal change in concentration distribution of the gas 6 to be analyzed. FIG. 13A shows the distribution of the two-dimensional region of the analysis target gas 6, with the point having the peak concentration value as the reference, the X + and X- axes, the Y + and Y- axes, the V + and V- axes, the U + and Evaluate the concentration distribution in the four directions of the U-axis.

FIG. 13B shows an example of a concentration distribution map. The concentration distribution diagram of FIG. 13B is an example of the X+ and X-axes. With the concentration peak value D0 as the 0 point, the concentration analysis values are D1, D2, . D-2, . . . are distribution charts.

S _** (** represents an axial direction such as X+ or X−) in FIG. 13B is a value for evaluating the degree of spread of the concentration distribution map in FIG. 13A, and is obtained by Equation (4). Spread evaluation is performed for each of X+ and X-.

FIG. 13B shows current time t1 of coordinate values having density peak values, peak density values, spread evaluation values S _X− , S _X+ , S _Y− , S _Y+ , S _U− , S _U+ , S _V− , S _V+ and the value at the previous time t0, and the time change evaluation value of the spread of the gas concentration distribution is calculated in the right column.

FIG. 14 shows a composite/display image 553 displayed in this embodiment. A graphic image is superimposed on the composite/display image 55 (see FIG. 6) of the first embodiment to make the spread of the distribution easier to see. The composite/display image 553 is a graphic image in which G10, G11, G12, and G13 are superimposed, where G10 is the change in density peak coordinates (R, φ), and G11 and G12 are the time from S _X− to S _V+ . Among the evaluation values of change, those with large changes selected are indicated by arrows of sizes corresponding to the evaluation values. Using the change in the spread of these gases over time to predict a dangerous area, G13 advises the direction of evacuation.

FIG. 15 is a flow chart showing the processing flow of the gas visualization application unit 735 according to the fourth embodiment. The gas visualization application unit 735 is activated, performs initial settings (S10), and subsequently executes the THz wave control process S1 and the analysis process S2.

The gas visualization application unit 735 reads out the recorded concentration data (S40), and detects the point where the concentration becomes a peak value (S41). If there are a plurality of gases to be analyzed, the gas visualization application unit 735 performs analysis on each of them.

Next, the gas visualization application unit 735 calculates evaluation parameters such as distribution spread (S42) and records them (S43).

The gas visualization application unit 735 reads evaluation parameters such as the spread of the distribution at the previous time (S44), and calculates the time change of the parameters (S45). The gas visualization application unit 735 selects significant temporal changes in evaluation parameters (S46).

The gas visualization application unit 735 detects the exit of the evacuation route and obstacles from the background image (S47), and determines the recommended evacuation direction (S48). S40 to S49 constitute a second extended analysis process S5 of the analysis process S2.

The gas visualization application unit 735 sends significant evaluation parameters and evacuation directions to the display process S3 (S49).

The gas visualization application unit 735 generates the composite/display image 553 shown in FIG. 14 and displays it on the display 141 (S3). Further, in S32, the continuation is judged and the process ends.

As described above, according to the fourth embodiment, the evaluation value corresponding to the time change of the gas concentration distribution is calculated, the time change of the dangerous area is predicted, and the instruction of the effective evacuation route, etc. is displayed in the synthesized image. can be presented within

[Fifth embodiment]
A fifth embodiment will be described with reference to FIGS. 16 and 17. FIG. FIG. 16A is a front view of the THz wave detection device 100c according to the fifth embodiment. FIG. 16B is a side sectional view of the THz wave detection device 100c according to the fifth embodiment.

In FIG. 16A, the THz wave detection device 100c is housed in a housing cover 410 so as to cover the controller 7, and is equipped with a THz wave transmitter/receiver 1a. The THz wave detection device 100c analyzes the user's odor or the like while photographing the user himself/herself with the front camera 143 . For example, it detects the components of fragrances contained in softening agents for laundry, and assists in paying attention so as not to disturb the surroundings.

The THz wave detection device 100c includes a display 45a with a touch panel. A person is displayed on the touch panel display 45a, and a mark G14 is superimposed on the person. The shape of the mark G14 corresponds to the cause of the odor registered in advance, and the strength of the odor is indicated by the number of horizontal bars G15 at the top of the screen.

FIG. 17 is a flow chart showing the processing flow of the gas visualization application unit 735 in the fifth embodiment. After being activated, the gas visualization application unit 735 performs initial settings (S10), and subsequently executes the THz wave control process S1 and the analysis process S2.

The gas visualization application unit 735 recognizes the person area from the camera image received from S29 (S50), and generates a density image of the person area (S27). The gas visualization application unit 735 creates a graphic image using the density image (S28), and creates the mark G14 and the like shown in FIG. 16A (S29).

The gas visualization application unit 735 performs image synthesis processing, creates a synthesized/display image 554 (S30), and displays the synthesized/display image 554 on the touch panel display 45a (S31). Further, in S32, the continuation is determined and the process ends.

As described above, according to the fifth embodiment, it is possible to easily analyze the smell of the photographer himself/herself by utilizing a camera unit for self-photographing such as a smartphone.

The present invention is not limited to the embodiments described with reference to FIGS. 1 to 17, and part of the configuration of one embodiment can be replaced with another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. All of these belong to the scope of the present invention, and numerical values, messages, etc. appearing in texts and drawings are only examples, and even if different ones are used, the effect of the present invention is not impaired.

Also, the functions and the like of the present invention may be implemented by hardware, for example, by designing a part or all of them using an integrated circuit. It may also be implemented in software by a microprocessor unit, CPU, etc. interpreting and executing an operating program. Moreover, the implementation range of software is not limited, and hardware and software may be used together.

In the above embodiment, the object to be detected is the gas 6 to be analyzed, and the background reflection object is the scenery in the real space where the gas 6 to be analyzed floats, such as a structure such as a vehicle or living room. The device 100 may be used as an inspection device at the time of product shipment. In this case, the product may be a background reflecting object, and the object to be detected may be a foreign substance in the product. For example, a foreign substance mixed in food may be detected. It may also be used as an inspection for contamination of non-food products such as tires. Furthermore, it may be used as a pharmaceutical shipping inspection device and used for coating inspection of multi-layer coated drugs. It may also be used to identify the contents of a plastic bottle at a baggage inspection site such as an airport, or may be used to identify the contents without unlocking a suitcase.

Reference Signs List 1: THz wave transmitter/receiver 2: Analysis unit 3: Camera 4: Visualization unit 5: Background reflector 6: Analysis target gas 7: Controller 10: Smartphone 11: Transmitter 12: Receiver 13: Transmission control unit 14: Antenna 15a : Transmitted wave 15b : Reflected terahertz wave 45a : Display with touch panel

Claims (11)

a terahertz wave transceiver including a transmitter for transmitting terahertz waves and a receiver for receiving reflected terahertz waves reflected by a reflector existing behind an object irradiated with the terahertz waves ;
camera and
a display;
an information processing device comprising the terahertz wave transceiver, the camera, and the display,
The transmitter irradiates a terahertz wave based on a transmission signal in which a frequency including a specific frequency is swept,
The information processing device is
analysis processing for analyzing the received terahertz wave;
a display image generation process for generating a display image for superimposing an image based on the analysis result on an image captured by the camera based on the analysis result of the analysis process, and displaying the image on the display;
In the analysis process,
detecting a frequency difference between the frequency of the terahertz wave transmitted by the transmitter and the frequency of the terahertz wave received by the receiver;
a distance calculation process for calculating a distance from the terahertz wave transceiver to the reflector based on the frequency difference;
an object identification process for identifying the type of the object based on the frequency attenuated in the received terahertz wave;
Based on the intensity of the terahertz wave emitted from the transmitter, the amount of attenuation of the received terahertz wave with respect to the terahertz wave emitted from the transmitter, and the distance, the amount of change in the spread of the distribution of the object is calculated. distribution calculation processing;
and run
In the display image generation process,
generating a display image according to the amount of change in the spread of the distribution according to the background of the image captured by the camera, and displaying the display image on the display by superimposing the display image on the background image;
A terahertz wave detection device characterized by: In the terahertz wave detection device according to claim 1,
In the display image generation process,
further executing a depth image generation process for generating a depth image having a display mode different according to the distance;
using the depth image as the background image, superimposing a display image corresponding to the amount of change in the spread of the distribution on the depth image, and displaying the display on the display;
A terahertz wave detection device characterized by: In the terahertz wave detection device according to claim 1,
In the display image generation process, an image captured by the camera is used as the image of the background, and a display image corresponding to the amount of change in spread of the distribution is superimposed on the image captured by the camera and displayed on the display. do,
A terahertz wave detection device characterized by: In the terahertz wave detection device according to claim 1,
In the distribution calculation process, when R is the signal intensity of a flat portion where there is no absorption by the object, S is the signal intensity of the frequency attenuated by the object absorbing the terahertz wave, and d is the distance , calculating the distribution of the object by the following formula (1), and calculating the amount of change in the spread of the distribution based on the information about the calculated distribution;
Object distribution = R/S/d (1)
A terahertz wave detection device characterized by: In the terahertz wave detection device according to claim 1,
the object is an invisible gas,
The display image corresponding to the amount of change in the spread of the distribution is an image showing the amount of change in the spread of the gas distribution,
superimposing an image showing the amount of change in the spread of the gas distribution on the background image and displaying it on the display;
A terahertz wave detection device characterized by: In the terahertz wave detection device according to claim 1,
The terahertz wave detection device is attached to a support base that supports the terahertz wave detection device, and an expansion device that includes an expansion rod connected to the support base,
Measuring the object a plurality of times by varying the amount of expansion and contraction of the expansion rod by the terahertz wave detection device,
In the distribution calculation process, the maximum angles θ1 and θ2 are calculated when the width direction end of the object is measured from the terahertz wave detection device in each measurement, and the expansion and contraction amount between the multiple measurements is calculated. When the analysis distance difference consisting of the difference is l, the distance Lg from the terahertz wave detection device to the object is calculated by the following formula (2),
When the signal intensity of the flat portion where there is no absorption by the object is R, the signal intensity of the frequency attenuated by the object absorbing the terahertz wave is S, and the distance Lg, the following formula (3) calculating the distribution of the object by calculating the amount of change in the spread of the distribution based on the information about the calculated distribution;
Lg=l tan θ1/(tan θ2−tan θ1) (2)
Spread of object distribution = R/S/Lg (3)
In the display image generation process,
generating a display image corresponding to a new amount of change in the spread of the distribution obtained by updating the amount of change in the spread of the distribution according to the background of the image captured by the camera;
displaying the new display image superimposed on the background image on the display;
A terahertz wave detection device characterized by: In the terahertz wave detection device according to claim 1,
In the display image generation process,
Acquire the spread of the distribution of the object on a plurality of axes, obtain the center of the spread of the distribution and an evaluation parameter corresponding to the spread of the distribution, and generate graphic image data showing the amount of time-series change in the evaluation parameter. Generate as a display image according to the amount of change in the spread of the distribution,
displaying the graphic image data superimposed on the background image on the display;
A terahertz wave detection device characterized by: The terahertz wave detection device according to claim 7,
In the display image generation process,
further generating a graphic image showing a route in a direction different from the direction of change along the time series at the position where the amount of change in the spread of the distribution is large, based on the time-series change in the evaluation parameter;
displaying a graphic image indicating the route superimposed on the background image on the display;
A terahertz wave detection device characterized by: The terahertz wave detection device according to claim 3,
The object is an odor component,
In the analysis process, an odor component is specified based on the reflected terahertz wave,
In the display image generation process, a graphic image indicating the type of the identified odor component is generated,
A region in which the real space in which the odor component is detected is captured in the image captured by the camera is specified, and a graphic image indicating the type of the specified odor component is displayed on the specified region of the background image. superimposed and displayed on the display;
A terahertz wave detection device characterized by: a step of irradiating a two-dimensional region containing an object with terahertz waves based on a transmission signal containing a specific frequency;
obtaining an image of the background captured by the camera;
a step of receiving reflected terahertz waves reflected by a reflector existing behind the object ;
analyzing the received reflected terahertz wave;
generating a display image based on the analysis result based on the analysis result in the step of analyzing the reflected terahertz wave;
a step of superimposing the display image on a background image captured by the camera and displaying the image on a display;
The terahertz wave is a terahertz wave based on a transmission signal whose frequency is swept,
In the step of analyzing the received reflected terahertz wave,
detecting a frequency difference between the frequency of the terahertz wave and the frequency of the reflected terahertz wave;
calculating the distance from the terahertz wave transceiver to the reflector based on the frequency difference;
calculating an amount of change in the spread of the distribution of the object based on the intensity of the terahertz wave, the amount of attenuation of the reflected terahertz wave with respect to the terahertz wave, and the distance;
Identifying the type of the object based on the frequency attenuated in the reflected terahertz wave,
In the step of generating a display image based on the analysis result,
generating a display image corresponding to the amount of change in the spread of the distribution according to the background of the image captured by the camera;
A terahertz wave detection method characterized by: Connected to a terahertz wave transceiver including a transmitter that transmits terahertz waves and a receiver that receives reflected terahertz waves reflected by a reflecting object,
An information processing device having a camera and a display,
The terahertz wave transmitter/receiver irradiates a terahertz wave based on a transmission signal in which a frequency including a specific frequency is swept,
The information processing device is
analysis processing for analyzing received reflected terahertz waves;
a display image generation process for generating a display image by superimposing an image based on the analysis result on an image captured by the camera based on the analysis result of the analysis process and outputting it to the display;
In the analysis process,
detecting a frequency difference between the frequency of the terahertz wave transmitted by the transmitter and the frequency of the terahertz wave received by the receiver;
distance calculation processing for calculating a distance from the terahertz wave transmitter/receiver to a reflecting object existing behind an object irradiated with the terahertz wave based on the frequency difference;
an object identification process for identifying the type of the object based on the frequency attenuated in the received terahertz wave;
Based on the intensity of the terahertz wave emitted from the transmitter, the amount of attenuation of the received terahertz wave with respect to the terahertz wave emitted from the transmitter, and the distance, the amount of change in the spread of the distribution of the object is calculated. distribution calculation processing;
and run
In the display image generation process,
generating a display image corresponding to the amount of change in the spread of the distribution according to the background of the image captured by the camera, superimposing the display image on the background image, and displaying the display on the display;
An information processing device characterized by:

Images