Human body detection device

Abstract

Provided is a human body detection device configured to sensitively perform both proximity detection and cross-cut detection. The human body detection device (1) comprises a lens array (3). The lens array (3) has a first region (95) comprising one or more than one first lens (311p, 311q) and a second region (96) comprising one or more than one second lens (311w). The one or more first lenses (311p, 311q) are each one or more lenses in which the one or more first lenses (311p, 311q) are each formed by the one or more first lenses (311p, 311q). One of a plurality of first infrared receiving paths defined by the plurality of detectors of the thermoelectric elements and the respective first lenses of the one or more than one first lenses (311p, 311q) and one of a plurality of second infrared receiving paths defined by the plurality of detectors and one lens (311) adjacent to the respective first lenses of the one or more than one first lenses (311p, 311q) overlap each other. The one or more second lenses (311w) are, respectively, one or more lenses, in each of which one or more second lenses (311w) are, respectively, one or more lenses, a plurality of first infrared receiving paths defined by a respective one of the one or more second lenses (311w) and the plurality of detectors and a plurality of second infrared receiving paths defined by one lens (311) adjacent to the respective one of the one or more second lenses (311w) and the plurality of detectors do not overlap each other.

Description

Technical Field

[0001] The present disclosure relates to a human body detection device, and more particularly to a human body detection device including a thermoelectric element configured to detect infrared radiation from a human body. Background Art

[0002] Patent Document 1 describes an infrared human body detector including: a thermoelectric element; and an optical system disposed in front of a light-receiving surface of the thermoelectric element. The thermoelectric element includes a plurality of device elements having different output voltage polarities. The optical system includes a mirror and a lens body. The lens body includes a plurality of lenses. In the infrared human body detector, the output of the thermoelectric element is amplified by an amplifier, then the output is passed through a band-pass filter, and a comparison circuit determines whether the output is higher than or equal to a reference level. Thus, the infrared human body detector can detect the presence / absence or movement of a person.

[0003] For example, when the distance from the thermoelectric element to the detection area is long as in the case where a human body detection device disposed on the ceiling of a warehouse detects a person passing through a path below it, it is desirable to be able to perform both proximity detection and crossing detection sensitively in the detection area. Note that proximity detection is the detection of a person moving at a moving speed with a proximity component (the rate component approaching the thermoelectric element) greater than a crossing component (the rate component at which the person crosses the light-receiving path of the infrared radiation from the person). Crossing detection is the detection of a person moving at a moving speed with a crossing component greater than a proximity component.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2000-329860 Summary of the Invention

[0007] An object of the present disclosure is to provide a human body detection device configured to perform both proximity detection and crossing detection sensitively.

[0008] A human body detection device according to an aspect of the present disclosure includes a thermoelectric element, a lens array, and a determination unit. The thermoelectric element includes a plurality of detectors. The lens array includes a plurality of lenses configured to focus infrared radiation onto the thermoelectric element. The determination unit is configured to output a human body detection signal based on an output signal of the thermoelectric element. Each of the plurality of lenses and the plurality of detectors define a plurality of infrared reception paths. The plurality of infrared reception paths include a plurality of first infrared reception paths and a plurality of second infrared reception paths. The plurality of first infrared reception paths are defined by any one of the plurality of lenses and the plurality of detectors. The plurality of second infrared reception paths are defined by one lens included in the plurality of lenses and adjacent to the any one lens and the plurality of detectors. The lens array has a first region and a second region. The first region includes one or more than one first lenses among the plurality of lenses. The second region includes one or more than one second lenses among the plurality of lenses. Each of the one or more than one first lenses is one or more than one lens such that, in each of the one or more than one first lenses, one first infrared reception path among the plurality of first infrared reception paths defined by the corresponding first lens among the one or more than one first lenses and the plurality of detectors and one second infrared reception path among the plurality of second infrared reception paths defined by one lens included in the plurality of lenses and adjacent to the corresponding first lens among the one or more than one first lenses and the plurality of detectors overlap each other. Each of the one or more than one second lenses is one or more than one lens such that, in each of the one or more than one second lenses, the plurality of first infrared reception paths defined by the corresponding second lens among the one or more than one second lenses and the plurality of detectors and the plurality of second infrared reception paths defined by one lens included in the plurality of lenses and adjacent to the corresponding second lens among the one or more than one second lenses and the plurality of detectors do not overlap each other. Description of the Drawings

[0009] Figure 1 is a perspective view of a human body detection device according to the present embodiment;

[0010] Figure 2 is a perspective view of a detection space and a detection area of the human body detection device;

[0011] Figure 3 is an explanatory diagram of an approaching component and a cross-cutting component of a person's moving speed;

[0012] Figure 4 is an exploded perspective view of the human body detection device;

[0013] Figure 5 is Figure 4The plan view of the housing when viewed from the cylindrical portion of the housing;

[0014] Figure 6 is Figure 4 The block diagram of the circuit unit of the detection sensor shown;

[0015] Figure 7 (A) is the plan view of the surface of the thermoelectric element;

[0016] Figure 7 (B) is along Figure 7 The sectional view of the line X1-X1 in (A);

[0017] Figure 8 The plan view of the relationship between the detection area and the individual detection area;

[0018] Figure 9 is Figure 8 The enlarged view of a part of;

[0019] Figure 10 is Figure 4 The plan view of the inside of the lens array when viewed from the rear side of the lens array; and

[0020] Figure 11 The plan view of the inside of the lens array when viewed from the rear side of the lens array of the third modification. Detailed Description of the Invention

[0021] (1) Embodiment

[0022] Hereinafter, a human body detection device according to the present embodiment will be described with reference to the drawings.

[0023] (1-1) Overview of the Human Body Detection Device

[0024] As Figure 1 and Figure 2 shown, the human body detection device 1 according to the present embodiment detects infrared radiation from a person to detect the person. The human body detection device 1 is suitable for being installed, for example, on the ceiling of a warehouse to detect a person passing through a path under its lower side.

[0025] In the following description, an example is shown in which the human body detection device 1 is installed on the ceiling of a warehouse to detect a person passing through a path in the warehouse. Note that the human body detection device 1 is not limited to use in a warehouse. For example, the human body detection device 1 can be installed in a place other than a warehouse (e.g., a street lamp) to detect the presence of a person passing around the place. Note that the installation place of the human body detection device 1 is not limited to a place higher than a person such as a ceiling and a street lamp, and can also be a wall surface.

[0026] The human body detection device 1 is installed on the ceiling of the warehouse such that the detection direction of the human body detection device 1 points downward. In this way, the human body detection device 1 detects a person passing through the path (the path of the warehouse) below it from its installation position. The path of the warehouse has a rectangular shape (i.e., a strip shape). Therefore, the detection area R1 of the human body detection device 1 is formed on the path to have a rectangular shape (i.e., a strip shape) corresponding to the shape of the path of the warehouse. Note that since the path of the warehouse often has a rectangular shape, the detection area R1 preferably has a rectangular shape. This embodiment shows an example in which the detection area R1 has a rectangular shape, but the shape of the detection area R1 is not limited to a rectangular shape.

[0027] The human body detection device 1 has a conical detection space S1 defined by the installation position P1 of the human body detection device 1 on the ceiling of the warehouse and the detection area R1 provided on the path of the warehouse. The human body detection device 1 detects a person moving across the detection space S1.

[0028] More specifically, as Figure 3 shown, for a person Q1a moving in the edge portion R11 (first detection area) of the detection area R1, it is characterized in that the approaching component (approach rate) V11 of the moving speed V1 of the person Q1a is large, and the crossing component (crossing rate) V12 of the moving speed V1 of the person Q1a is small. In addition, for a person Q1b moving in the central portion R12 (second detection area) of the detection area R1, it is characterized in that the approaching component (approach rate) V11 of the moving speed V1 of the person Q1b is small, and the crossing component (crossing rate) V12 of the moving speed V1 of the person Q1b is large.

[0029] Therefore, the human body detection device 1 is set such that in the edge portion R11 of the detection area R1, proximity detection is performed sensitively, and in the central portion R12 of the detection area R1, crossing detection is performed sensitively. That is, in this embodiment, the first detection area for performing proximity detection sensitively is arranged in the edge portion R11 of the detection area R1, and the second detection area for performing crossing detection sensitively is arranged in the central portion R12 of the detection area R1.

[0030] Note that the "moving speed V1" is a vector having a direction from the positions of the persons Q1a and Q1b toward the traveling directions of the persons Q1a and Q1b and having a magnitude equal to the absolute value of the moving speed V1. The "approach component V11" is the component of the moving speed V1 that is parallel to the propagation paths T1a and T1b of the infrared radiation from the persons Q1a and Q1b toward the human body detection device 1 (i.e., the component by which the persons Q1a and Q1b approach the human body detection device 1). The "transverse component V12" is the component of the moving speed V1 that is orthogonal to the propagation paths T1a and T1b (i.e., the transverse component that transverses the propagation paths T1a and T1b). In addition, "approach detection" is the detection of a person moving at a moving speed such that the approach component V11 is greater than the transverse component V12. In addition, "transverse detection" is the detection of a person moving at a moving speed such that the transverse component V12 is greater than the approach component V11.

[0031] (1-2) Configuration of the Human Body Detection Device

[0032] As Figure 4 shown, the human body detection device 1 includes a detection sensor 2, a lens array 3, and a housing 4.

[0033] The detection sensor 2 receives infrared radiation from a person in the detection area R1, and the detection sensor 2 detects the presence / absence of a person in the detection area R1 based on the infrared radiation received thereby. The detection sensor 2 is, for example, a can package type sensor. More specifically, the detection sensor 2 includes a housing 21 (also referred to as a lid), a substrate 22 (also referred to as a trunk), a plurality of wires 23, and a circuit unit including a thermoelectric element 24.

[0034] The housing 21 has, for example, a can shape (i.e., a cylindrical shape having a front end surface provided with a bottom and a base end surface having an opening). The front end surface of the housing 21 has, for example, a window portion 21a having a rectangular shape for allowing infrared radiation from a person as a detection object to enter. The window portion 21a is sealed with a transparent plate member (e.g., a glass plate or a transparent resin plate).

[0035] The substrate 22 is a member that closes the opening in the base end surface of the housing 21 and supports the plurality of wires 23. The substrate 22 has, for example, a disk shape. The substrate 22 is attached to the base end of the housing 21 to close the opening in the base end surface of the housing 21. The substrate 22 has an outer peripheral surface provided with a protrusion 22a that can be fitted into a positioning recess 42a of the housing 4, which will be described later.

[0036] A plurality of wires 23 include wires 23 for outputting signals to an external output circuit unit, wires 23 for power supply, and wires 23 for grounding. A plurality of wires 23 are provided for the substrate 22 to penetrate the substrate 22. The plurality of wires 23 are led out from inside the housing 21 through the substrate 22 to the outside. The plurality of wires 23 are electrically connected to the circuit units in the housing 21.

[0037] A circuit unit including a thermoelectric element 24 is accommodated inside the housing 21. The thermoelectric element 24 is arranged at the rear side of the window portion 21a of the housing 21.

[0038] The lens array 3 is arranged in front of the detection sensor 2 to collect infrared radiation from a person in the detection area R1 onto the thermoelectric element 24 in the detection sensor 2. The lens array 3 has, for example, a hemispherical shell shape. The lens array 3 includes a lens array body 31 and a joint portion 32.

[0039] The lens array body 31 has a hemispherical shell shape. The lens array body 31 has a rear surface with a hemispherical concave shape. A plurality of lenses 311 are provided on the rear surface of the lens array body 31 (see Figure 10 ). The plurality of lenses 311 form individual detection areas r1 in the detection area R1 (see Figure 8 ). The individual detection areas r1 correspond one-to-one with the lenses 311. Each lens 311 collects infrared radiation from a person passing through the corresponding individual detection area in the individual detection area r1 onto the light-receiving surface 24a of the thermoelectric element 24. Therefore, the detection area R1 has the same number of individual detection areas r1 as the plurality of lenses 311. The detection area R1 is formed by a plurality of individual detection areas r1 corresponding one-to-one with the plurality of lenses 311. The shape of the detection area R1 is the shape of a configuration including the plurality of individual detection areas r1.

[0040] Note that in the present embodiment, as will be described later, the shape H1 of the configuration (lens configuration) of the plurality of lenses 311 is a rectangular shape (i.e., a strip shape), and thus the shape of the configuration of the plurality of individual detection areas r1 is a rectangular shape (i.e., a strip shape). In addition, the shape of the configuration of the plurality of individual detection areas r1 is a rectangular shape (i.e., a strip shape), and thus the detection area R1 has a rectangular shape (i.e., a strip shape). Details of the configuration of the plurality of lenses 311 will be described later.

[0041] The joint portion 32 is a portion that is fitted into a peripheral wall portion 43 of the housing 4, which will be described later. The joint portion 32 has, for example, a shortened cylindrical shape. The joint portion 32 projects rearward from the outer peripheral end portion of the lens array body 31. The joint portion 32 has a rear end provided with a pair of claw portions 32a, and the pair of claw portions 32a will be caught by a pair of snap portions 41b of the housing 4, which will be described later.

[0042] The housing 4 is a member for accommodating the detection sensor 2 and supporting the lens array 3. The housing 4 includes a substrate 41, a cylindrical portion 42, and a peripheral wall portion 43.

[0043] The substrate 41 has, for example, a disk shape. The substrate 41 has a hole 41a at its center. Infrared radiation transmitted through the lens array body 31 passes through the hole 41a. The substrate 41 has an outer peripheral portion provided with a pair of snap portions 41b that will catch a pair of claw portions 32a of the lens array 3.

[0044] The cylindrical portion 42 is the portion that will accommodate the detection sensor 2. The cylindrical portion 42 is cylindrical. The cylindrical portion 42 projects rearward from the center of the rear surface of the substrate 41. The cylindrical portion 42 has an internal space that communicates with the hole 41a at the center of the substrate 41. The cylindrical portion 42 has an annular rear end 42b provided with positioning recesses 42a at two positions in the circumferential direction, and the protrusion 22a of the detection sensor 2 can be fitted into the positioning recesses 42a (see Figure 5 ). One of the positioning recesses 42a is a positioning recess for aligning the orientation around the central axis of the detection sensor 2 with the 0-degree orientation. The other of the positioning recesses 42a is a positioning recess for aligning the orientation around the central axis of the detection sensor 2 with the 45-degree orientation.

[0045] Note that the "0-degree orientation" is the following orientation around the central axis of the detection sensor 2. According to this orientation, one side of the light-receiving surface 24a, which has a square shape and will be described later, of the thermoelectric element 24 is parallel or orthogonal to the long side direction of the lens arrangement shape (rectangular shape) of the lens array 3 (i.e., the first diagonal line 24b of the thermoelectric element 24, which will be described later, is inclined 45 degrees with respect to the long side direction of the lens arrangement shape). In addition, the "45-degree orientation" is the following orientation around the central axis of the detection sensor 2. According to this orientation, one side of the light-receiving surface 24a, which has a square shape and will be described later, of the thermoelectric element 24 is inclined 45 degrees with respect to the long side direction of the lens arrangement shape (i.e., the first diagonal line 24b of the thermoelectric element 24, which will be described later, is parallel to the long side direction of the lens arrangement shape). Note that in the present embodiment, the protrusion 22a of the detection sensor 2 is fitted into the positioning recess 42a of the two positioning recesses 42a of the cylindrical portion 42 that aligns the orientation around the central axis of the detection sensor 2 with the 45-degree orientation.

[0046] The peripheral wall portion 43 is the portion to be fitted into the engaging portion 32 of the lens array 3. The peripheral wall portion 43 projects forward from the outer peripheral edge of the front surface of the substrate 41 and is provided in the circumferential direction on the front surface of the substrate 41.

[0047] In the human body detection device 1, the detection sensor 2 is accommodated inside the cylindrical portion 42 of the housing 4. In this accommodation state, the window portion 21a of the detection sensor 2 is disposed behind the hole 41a of the substrate 41 of the housing 4. In addition, the protrusion 22a of the detection sensor 2 is fitted into one of the positioning recesses 42a of the substrate 41. Thus, the orientation around the central axis of the detection sensor 2 is fixed to the "45-degree orientation". In addition, the lens array 3 is disposed in front of the housing 4. In this arrangement state, a pair of claw portions 32a of the lens array 3 are caught by a pair of snap fasteners 41b of the housing 4. Thus, the lens array 3 is fixed to the housing 4.

[0048] (1-3) Details of the circuit unit of the detection sensor

[0049] As Figure 6 shown, the circuit unit of the detection sensor 2 includes a thermoelectric element 24, a signal processor 25, and a determination unit 26.

[0050] The thermoelectric element 24 is an infrared receiving element that receives infrared radiation C1 from a person in the detection area R1 via the lens array 3.

[0051] The signal processor 25 performs signal processing on the output signal of the thermoelectric element 24 to output a voltage signal proportional to the output signal. More specifically, the signal processor 25 converts the current signal, which is the output signal output from the thermoelectric element 24, into a voltage signal, and the signal processor 25 amplifies the voltage signal included in the converted voltage signal and falling within a predetermined frequency range (for example, 0.1 Hz to 10 Hz), and outputs the amplified signal.

[0052] The determination unit 26 outputs a human body detection signal based on the level of the voltage signal output from the signal processor 25 (i.e., based on the output signal of the thermoelectric element 24). The determination unit 26 includes a first determination unit 261 and a second determination unit 262. The first determination unit 261 compares the first threshold value with the level of the voltage signal, and when it determines that the level of the voltage signal exceeds the first threshold value, the first determination unit 261 outputs a human body detection signal. The second determination unit 262 compares the second threshold value with the level of the voltage signal, and when a set of changes in which the level of the voltage signal exceeds the second threshold value, is lower than the second threshold value, and then exceeds the second threshold value again continues for a predetermined number of times, the second determination unit 262 outputs a human body detection signal. Note that the first threshold value and the second threshold value are absolute values. In addition, the second threshold value is a value smaller than the first threshold value. For example, the first threshold value is 0.6 V, and the second threshold value is 0.3 V.

[0053] Note that based on a person (for example, Figure 3When a person Q1b) moves in the detection space S1 at a relatively large moving speed in the transverse component V12, a first threshold value is preset based on the voltage signal. That is, the first threshold value is a threshold value (threshold value for transverse detection) for detecting a person (e.g., person Q1b) moving at a relatively large moving speed in the transverse component V12. In addition, based on the voltage signal when a person (e.g., Figure 3 When a person Q1a) moves in the detection space S1 at a relatively large moving speed in the approaching component V11, a second threshold value is preset. That is, the second threshold value is a threshold value (threshold value for approaching detection) for detecting a person (e.g., person Q1a) moving at a relatively large moving speed in the approaching component V11.

[0054] (1-4) Structure of the thermoelectric element

[0055] As Figure 7 shown in (A) of Figure 7 and (B) of

[0056] The thermoelectric element 24 of the present embodiment is, for example, a quad element including four detectors 242 formed on a single thermoelectric substrate 241. The four detectors 242 are arranged on the thermoelectric substrate 241 in a 2×2 array (matrix). Note that, in the present embodiment, the thermoelectric element is a quad element including four detectors 242 arranged in a 2×2 array (matrix). Note that the thermoelectric element 24 is at least an element including (N×N) detectors 242 arranged in an N×N array, where N is an integer greater than or equal to 2.

[0057] The thermoelectric substrate 241 is a thermoelectric substrate. The thermoelectric substrate 241 has a square plate shape in a plan view. The thermoelectric substrate 241 is formed of, for example, a single crystal LiTaO3 substrate. Among the main surfaces on both sides of the thermoelectric substrate 241, the main surface facing the lens array 3 is defined as the front surface, and the main surface opposite to the front surface is defined as the back surface.

[0058] Each of the four detectors 242 is a capacitor, which includes: a front-side electrode 2421 formed on the front surface 241a of the thermoelectric substrate 241; a back-side electrode 2422 formed on the back surface 241b of the thermoelectric substrate 241; and a portion 2423 of the thermoelectric substrate 241 located between the front-side electrode 2421 and the back-side electrode 2422.

[0059] The front-side electrode 2421 and the back-side electrode 2422 are, for example, square and have the same size. That is, the shape of each of the four detectors 242 in a plan view is a square shape. The four detectors 242 include a first detector 242A with the polarity of the front-side electrode 2421 being positive and a second detector 242B with the polarity of the front-side electrode 2421 being negative. InFigure 7 In (A) thereof, the polarity of the front electrode 2421 of the first detector 242A is indicated by the reference numeral "+", and the polarity of the front electrode 2421 of the second detector 242B is indicated by the reference numeral "-". Each of the four detectors 242 has a light-receiving surface 424a on the front surface as the front electrode 2421.

[0060] As described above, the thermoelectric element 24 is a quaternary element including four detectors 242 arranged in a 2×2 array. The thermoelectric element 24 has a rectangular (e.g., square) light-receiving surface 24a in a plan view including the front electrodes 2421 of the four detectors 242. That is, the light-receiving surface 24a of the thermoelectric element 24 includes the light-receiving surfaces 242a of the four detectors 242 arranged in a 2×2 matrix. Thus, each of the plurality of individual detection regions r1 included in the detection region R1 includes four effective regions r11 to r14 corresponding to the light-receiving surfaces 242a of the four detectors 242 arranged in a 2×2 matrix (see Figure 8 ).

[0061] Among the four detectors 242 arranged in a 2×2 array in the thermoelectric element 24, two detectors 242 arranged in the direction along the first diagonal 24b of the rectangular light-receiving surface 24a are connected in parallel to each other, two detectors 242 arranged in the direction along the second diagonal 24c of the rectangular light-receiving surface 24a are connected in parallel to each other, two detectors 242 arranged in the row direction are connected in anti-parallel to each other, and two detectors 242 arranged in the column direction are connected in anti-parallel to each other.

[0062] In the thermoelectric element 24, the front electrodes 2421 of the two detectors 242 arranged in the direction along the first diagonal 24b have the same polarity. In addition, in the thermoelectric element 24, the front electrodes 2421 of the two detectors 242 arranged in the row direction have different polarities. In the thermoelectric element 24, the front electrodes 2421 of the two detectors 242 arranged in the column direction have different polarities.

[0063] This structure improves the detection sensitivity of the thermoelectric element 24.

[0064] Note that the "rectangle" as used in this embodiment refers to a right-angled quadrilateral and is a concept including a rectangle and a square. In Figure 7 's (A), as an example of the light-receiving surface 24a having a rectangular shape, a square light-receiving surface 24a is shown. The normal line of the center 200 of the light-receiving surface 24a of the thermoelectric element 24 can be regarded as the optical axis of the thermoelectric element 24.

[0065] (1-5) Details of the detection region

[0066] As Figure 8 shown, the detection area R1 has a rectangular shape (i.e., strip shape) corresponding to the shape of the path of the warehouse to be detected (rectangular shape (i.e., strip shape)). The long side direction of the detection area R1 is the same as the direction of the first diagonal line 24b of the light-receiving surface 24a of the thermoelectric element 24, and the short side direction of the detection area R1 is the same as the direction of the second diagonal line 24c of the light-receiving surface 24a of the thermoelectric element 24.

[0067] The detection area R1 includes a plurality of individual detection areas r1 corresponding one-to-one to the plurality of lenses 311. The plurality of individual detection areas r1 are arranged in a rectangular shape (i.e., strip shape) corresponding to the shape of the path of the warehouse to be detected. The rectangular shape (strip shape) of the detection area R1 is the shape of the configuration including the plurality of individual detection areas r1.

[0068] The plurality of individual detection areas r1 are arranged, for example, in a staggered manner. That is, the plurality of individual detection areas r1 include a plurality of rows 80 including the individual detection areas r1. Each of the plurality of rows 80 extends in the long side direction of the detection area R1. In addition, the plurality of rows 80 are arranged in a manner of being arranged in the short side direction of the detection area R1. Among the plurality of rows 80, Figure 8 the odd-numbered rows 80t counted from top to bottom on the paper surface of are offset by half an individual detection area in the long side direction of the row 80 with respect to the even-numbered rows 80u.

[0069] More specifically, in the central portion R12 (second detection area) of the detection area R1, the individual detection areas r1 are arranged in a staggered manner. Thus, each individual detection area r1 in the central portion R12 is arranged so as not to overlap with adjacent individual detection areas (i.e., the individual detection areas r1 on the upper side, lower side, left side, and right side of its Figure 8 paper surface). This configuration enables the thermoelectric element 24 to sensitively detect a person moving at a moving speed with a crossing rate V12 higher than the approaching rate V11 in the central portion R12 (second detection area) of the detection area R1.

[0070] In addition, within the left edge portion R11 (first detection area) of the detection area R1, the leftmost individual detection areas r1 of each of the plurality of rows 80 are arranged in a line (column 81) along the short side direction of the detection area R1. Therefore, each individual detection area r1 within the left edge portion R11 and the adjacent individual detection area r1 (i.e., in Figure 8The individual detection regions r1) on the upper side, lower side, and right side of the paper surface of Figure 8 partially overlap with the individual detection regions r1) on the upper side, lower side, and left side of the paper surface of

[0071] This overlap enables the thermoelectric element 24 to sensitively detect a person moving at a moving speed with an approach rate V11 higher than a transverse rate V12 in the edge portions R11 (first detection regions) on both sides of the detection region R1.

[0072] Each individual detection region r1 has four effective regions r11 to r14. The four effective regions r11 to r14 correspond one-to-one with the light-receiving surfaces 242a of the four detectors 242 arranged in a 2×2 array in the thermoelectric element 24. The four effective regions r11 to r14 are arranged in a 2×2 array. Each of the effective regions among the effective regions r11 to r14 has a shape (square shape) similar to the shape (square shape) of the light-receiving surface 242a of the detector 242.

[0073] Each individual detection region r1 is arranged such that the square shape is rotated by 45 degrees to become a rhombus shape. More specifically, the four effective regions r11 to r14 in each individual detection region r1 are arranged in a rhombus shape. That is, the direction of one diagonal 90a among the two diagonals 90a and 90b of each individual detection region r1 in which the four effective regions r11 to r14 are arranged in a 2×2 matrix coincides with the long side direction of the detection region R1 (i.e., the direction of the first diagonal 24b). In addition, the direction of the other diagonal 90b coincides with the short side direction of the detection region R1 (i.e., the direction of the second diagonal 24c).

[0074] Note that the direction of one diagonal 90a is the direction in which a set of effective regions r11 and r13 arranged diagonally among the four effective regions r11 to r14 are arranged. The direction of the other diagonal 90b is the direction in which another set of effective regions r12 and r14 arranged diagonally among the four effective regions r11 to r14 are arranged.

[0075] As described above, each individual detection region r1 (i.e., each individual detection region r1 in the leftmost column 81 and the rightmost column 82) included in the edge portions R11 (first detection regions) on both sides in the long side direction of the detection region R1 and the adjacent individual detection region r1 partially overlap (see Figure 8)。More specifically, four effective regions r11 to r14 in each individual detection region r1 included in the edge portions R11 on both sides in the detection region R1 partially overlap with one of the four effective regions r11 to r14 in each adjacent individual detection region r1 (see Figure 9 ). As Figure 9 shown, among the four effective regions r11 to r14 in the individual detection region r1T in the leftmost column 81 for example, the upper effective region r12 in the individual detection region r1T partially overlaps with the lower effective region r14 in the individual detection region r1U above the individual detection region r1T. In addition, the lower effective region r14 in the individual detection region r1T partially overlaps with the upper effective region r12 in the individual detection region r1D below the individual detection region r1T. In addition, the right effective region r13 in the individual detection region r1T partially overlaps with the left effective region r11 in the individual detection region r1R on the right side of the individual detection region r1T.

[0076] Each individual detection region r1 included in the central portion R12 (second detection region) of the detection region R1 does not overlap with the adjacent individual detection region r1. More specifically, the four effective regions r11 to r14 in each individual detection region r1 included in the central portion R12 of the detection region R1 do not overlap with the four effective regions r11 to r14 in the adjacent individual detection region r1.

[0077] (1-6) Details of the detection space

[0078] The detection space S1 (see Figure 2 and Figure 3 ) includes a plurality of infrared reception paths 70 (see Figure 2 ). In Figure 2In [the figure], only one infrared reception path 70 is shown, but there are multiple infrared reception paths 70 in the entire detection space S1. The multiple infrared reception paths 70 correspond one-to-one to all the effective areas r11 to r14 in the detection area R1 (that is, each individual detection area r1 includes all the effective areas r11 to r14 of the four effective areas r11 to r14). In addition, each of the multiple infrared reception paths 70 corresponds to any one of the multiple lenses 311 and corresponds to any one of the four detectors 242 of the thermoelectric element 24. The multiple infrared reception paths 70 extend from each of the effective areas r11 to r14 in all the effective areas r11 to r14 in the detection area R1 through a corresponding one of the lenses 311 to a corresponding one of the four detectors 242 of the thermoelectric element 24. In other words, the infrared reception path 70 is an infrared passing area through which an infrared radiation beam passes. The infrared radiation beam is used to form an image on the four light-receiving surfaces 242a of the detector 242 of the thermoelectric element 24. Still in other words, the infrared reception path 70 is an effective area for detecting infrared radiation from the human body. The number of infrared reception paths 70 is the same as the number of the multiple lenses 311 multiplied by the number of the four detectors 242 of the thermoelectric element 24.

[0079] The detection area R1 is a cross-section of the detection space S1 when the detection space S1 is cut along a virtual plane parallel to the path of the warehouse as the detection object (for example, a virtual plane corresponding to the surface of the path). Each of all the effective areas r11 to r14 in the detection area R1 is a cross-section of the corresponding infrared reception path in the infrared reception paths 70 when the corresponding infrared reception path is cut along the virtual plane.

[0080] (1-7) Lens configuration of the lens array

[0081] As Figure 10 shown, the multiple lenses 311 of the lens array 3 are arranged on the rear surface of the lens array 3 (more specifically, the rear surface of the lens array body 31). The multiple lenses 311 are, for example, aspherical lenses. The multiple lenses 311 are arranged longitudinally and laterally to form a lens group having a rectangular shape (that is, a strip shape) in a plan view from the rear surface side of the lens array 3 (hereinafter referred to as "the plan view of the lens array 3"). Thus, the shape H1 of the configuration including the multiple lenses 311 (that is, the lens group) in the plan view of the lens array 3 is a rectangular shape (that is, a strip shape).

[0082] The lens array 3 has a first portion M1 and a second portion M2 on the outer peripheral end of the lens array 3. The outer peripheral end of the lens array 3 is the periphery of the circular opening of the lens array 3. The first portion M1 is a portion on the outer peripheral end of the lens array 3. The second portion M2 faces the first portion M1 on the rear surface of the lens array 3 in a state where the center CT1 of the rear surface of the lens array 3 is located between the second portion M2 and the first portion M1. A plurality of lenses 311 (i.e., lens groups) are arranged in a strip shape (i.e., rectangular shape) on the rear surface of the lens array 3 from the first portion M1 side (e.g., close to the first portion M1) via the center CT1 toward the second portion M2 side (e.g., close to the second portion M2). The strip shape H1 is the shape of the arrangement (lens arrangement) of the plurality of lenses 311. That is, the shape H1 of the arrangement of the plurality of lenses 311 extends in a rectangular shape (i.e., strip shape) from the first portion M1 via the center CT1 toward the second portion M2 on the rear surface of the lens array 3. The shape H1 of the lens arrangement is a rectangular shape (i.e., strip shape) extending in the direction of the first diagonal 24b of the light receiving surface 24a of the thermoelectric element 24 in the plan view of the lens array 3.

[0083] The plurality of lenses 311 (i.e., lens groups) include lens rows 311s on the rear surface of the lens array 3, and the lens rows 311s include lenses arranged in the direction of the first diagonal 24b of the thermoelectric element 24. In addition, the plurality of lenses 311 (i.e., lens groups) include a plurality of lens rows 311s arranged parallel to the direction of the second diagonal 24c of the thermoelectric element 24 on the rear surface of the lens array 3. Among the plurality of lens rows 311s, Figure 10 the odd-numbered lens rows 311t counted from top to bottom on the paper surface are arranged by being offset by half a lens in the long side direction of the lens rows 311s with respect to the even-numbered lens rows 311u. That is, the plurality of lenses 311 are arranged in a staggered manner.

[0084] The plurality of lenses 311 includes a first lens 311p, 311q and a second lens 311w. The first lens 311p is a lens 311 in the left edge portion (first region) 95 in the long side direction of the shape H1 of the lens arrangement, and is, for example, a lens 311 in the leftmost column of the lens arrangement. The first lens 311p corresponds one-to-one with an individual detection region r1 in the left edge portion R11 (first detection region) in the long side direction of the detection region R1 (i.e., an individual detection region r1 in the leftmost column 81). The first lens 311q is a lens 311 in the right edge portion (first region) 95 in the long side direction of the shape H1 of the lens arrangement, and is, for example, a lens 311 in the leftmost column of the lens arrangement. The first lens 311q corresponds one-to-one with an individual detection region r1 in the right edge portion R11 (first detection region) in the long side direction of the detection region R1 (i.e., an individual detection region r1 in the rightmost column 82). The second lens 311w is a lens 311 in the central portion (second region) 96 in the long side direction of the shape H1 of the lens arrangement, and corresponds one-to-one with an individual detection region r1 in the central portion R12 (second detection region) in the long side direction of the detection region R1.

[0085] The arrangement and shape of each of the first lenses 311p in the leftmost column are set so as to satisfy the following condition A. Condition A is that in the detection region R1, one of the four effective regions r11 to r14 in each individual detection region r1 (i.e., each individual detection region r1 in the left edge portion R11) corresponding to the associated first lens 311p in the leftmost column of the first lenses 311p partially overlaps with one of the four effective regions r11 to r14 in an adjacent individual detection region r1.

[0086] In the present embodiment, as described above, for example, the individual detection regions r1 in the left edge portion R11 of the detection region R1 are arranged in a line along the second diagonal line 24c, thereby satisfying condition A. For this purpose, for example, the arrangement and shape of the first lens 311p in the leftmost column are set so that the individual detection regions r1 located in the left edge portion R11 in the detection region R1 and corresponding to the first lens 311p in the leftmost column are arranged in a line along the second diagonal line 24c. Specifically, the even-numbered first lenses 311pu among the first lenses 311p in the leftmost column have a halved size, so that the left ends of the first lenses 311p in the leftmost column are substantially aligned in a line. That is, the plurality of lenses 311 are arranged in a staggered manner, and thus the even-numbered first lenses 311pu among the first lenses 311p in the leftmost column will protrude substantially half a lens to the left. However, the even-numbered first lenses 311pu actually have a halved size, so that the left ends of the first lenses 311p in the leftmost column are substantially aligned in a line.

[0087] In addition, the arrangement and shape of each first lens 311q in the rightmost column are set to satisfy the following condition B. Condition B is that in the detection region R1, one of the four effective regions r11 to r14 in each individual detection region r1 (i.e., each individual detection region r1 in the right edge portion R11) corresponding to the associated first lens 311q in the first lenses 311q in the rightmost column partially overlaps with one of the four effective regions r11 to r14 in an adjacent individual detection region r1.

[0088] In the present embodiment, as described above, for example, the individual detection regions r1 in the right edge portion R11 in the detection region R1 are arranged in a line along the second diagonal 24c, thereby satisfying condition B. For this purpose, for example, the arrangement and shape of the first lenses 311q in the rightmost column are set such that the individual detection regions r1 located in the right edge portion R11 in the detection region R1 and corresponding to the first lenses 311q in the rightmost column are arranged in a line along the second diagonal 24c. Similarly, in this case, in a manner similar to that of the first lenses 311p, specifically, the even-numbered first lenses 311q in the rightmost column of the first lenses 311q have a halved size such that the right ends of the first lenses 311q in the rightmost column are substantially aligned in a line.

[0089] In addition, the arrangement and shape of each second lens 311w are set to satisfy the following condition C. Condition C is that in the detection region R1, the four effective regions r11 to r14 in each individual detection region r1 (i.e., each individual detection region r1 in the central portion R12) corresponding to the associated second lens 311w in the second lenses 311w do not overlap with the four effective regions r11 to r14 in an adjacent individual detection region r1.

[0090] In the present embodiment, as described above, for example, in the detection region R1, the individual detection regions r1 in the central portion R12 are arranged in a staggered manner, thereby satisfying condition C. For this purpose, for example, the arrangement and shape of the second lenses 311w are set such that the individual detection regions r1 in the central portion R12 corresponding to the second lenses 311w in the detection region R1 are arranged in a staggered manner.

[0091] Therefore, the lens array 3 has a first region 95, one of the first regions 95 includes a first lens 311p that satisfies condition A, and the other of the first regions 95 includes a first lens 311q that satisfies condition B. Therefore, a first detection region R11 is provided in the detection region R1, and in the first detection region R11, adjacent individual detection regions r1 partially overlap each other (that is, one of the effective regions r11 to r14 in one individual detection region r1 and one of the effective regions r11 to r14 in the individual detection region r1 adjacent to the one individual detection region r1 partially overlap each other). In addition, in the lens array 3, a second region 96 including a second lens 311w that satisfies condition C is provided. Therefore, a second detection region R12 is provided in the detection region R1, and in the second detection region R12, adjacent individual detection regions r1 do not overlap each other (that is, the effective regions r11 to r14 in adjacent individual detection regions r1 do not overlap each other).

[0092] (1-8) Details of the infrared reception path

[0093] As Figure 9 shown, a plurality of infrared reception paths 70 include a plurality of first infrared reception paths 70a and a plurality of second infrared reception paths 70b. The plurality of first infrared reception paths 70a are four infrared reception paths 70 defined by any one of the plurality of lenses 311 and the four detectors 242 of the thermoelectric element 24. The plurality of second infrared reception paths 70b are four infrared reception paths 70 defined by one lens 311 included in the plurality of lenses 311 and adjacent to the any one lens 311 and the four detectors 242.

[0094] In addition, as Figure 10 shown, as described above, the lens array 3 includes a first region 95 and a second region 96. The first region 95 of the lens array 3 is a region including one or more first lenses 311p, 311q among the plurality of lenses 311. In the present embodiment, the first region 95 is, for example, the edge portions on both sides in the long side direction of the shape H1 of the lens arrangement. The second region 96 of the lens array 3 is a region including one or more second lenses 311w among the plurality of lenses 311. In the present embodiment, the second region 96 is, for example, the central portion in the long side direction of the shape H1 of the lens arrangement. At this time, the first lenses 311p, 311q and the second lens 311w satisfy the following conditions Aa to Ca.

[0095] Condition Aa: One or more first lenses 311p are respectively one or more lenses as follows. In each of the one or more lenses, one of the four first infrared reception paths 70a defined by the corresponding first lens 311p among the one or more first lenses 311p and the four detectors 242 of the thermoelectric element 24 and one of the four second infrared reception paths 70b defined by one lens 311 included in the plurality of lenses 311 and adjacent to the corresponding first lens 311p among the one or more first lenses 311p and the four detectors 242 partially overlap each other.

[0096] Condition Ba: One or more first lenses 311q are respectively one or more lenses as follows. In each of the one or more lenses, one of the four first infrared reception paths 70a defined by the corresponding first lens 311q among the one or more first lenses 311q and the four detectors 242 of the thermoelectric element 24 and one of the four second infrared reception paths 70b defined by one lens 311 included in the plurality of lenses 311 and adjacent to the corresponding first lens 311q among the one or more first lenses 311q and the four detectors 242 partially overlap each other.

[0097] Condition Ca: One or more second lenses 311w are respectively one or more lenses as follows. In each of the one or more lenses, the four first infrared reception paths 70a defined by the corresponding second lens 311w among the one or more second lenses 311w and the four detectors 242 of the thermoelectric element 24 and the four second infrared reception paths 70b defined by one lens included in the plurality of lenses 311 and adjacent to the corresponding second lens 311w among the one or more second lenses 311w and the four detectors 242 do not overlap each other.

[0098] The one first infrared reception path 70a and the one second infrared reception path 70b that overlap each other correspond to each of the detectors included in the four detectors 242 and different from each other. In addition, the one first infrared reception path 70a and the one second infrared reception path 70b that overlap each other correspond to each of the detectors included in the four detectors 242 and having the same polarity of the front-side electrodes 2421. This improves the detection sensitivity of the thermoelectric element 24.

[0099] Condition Aa to Ca correspond to the content obtained by redefining Conditions A to C defined by using the effective regions r11 to r14 via the infrared reception path 70. Considering that the effective regions r11 to r14 are cross-sections of the infrared reception path 70 cut along the virtual plane, Conditions Aa to Ca correspond to Conditions A to C respectively and are substantially the same content as Conditions A to C.

[0100] (1-9) Lens array's lensless region

[0101] As Figure 10 shown, the lens array 3 has a lensless region W1 where a plurality of lenses 311 are not arranged. More specifically, the lensless region W1 is a region included in the rear surface of the lens array body 31 where a plurality of lenses 311 are not arranged. The lensless region W1 is arranged on both sides of a plurality of lenses 311 (i.e., lens groups) in the direction along the second diagonal 24c of the thermoelectric element 24, for example. The lensless region W1 is a region that overlaps with the area other than the path in the warehouse (i.e., the area other than the detection object). Since no lens 311 is arranged in the lensless region W1, the infrared radiation from the area corresponding to the lensless region W1 on the floor surface of the warehouse (i.e., the area other than the path) does not converge on the thermoelectric element 24. Thus, human detection is not performed in the area other than the path. As described above, setting the lensless region W1 for the lens array body 31 enables the detection region R1 to be formed only in the area where human detection is required (e.g., the path in the warehouse).

[0102] Note that additionally / alternatively, the lensless region W1 can be arranged on both sides of a plurality of lenses 311 (i.e., lens groups) in the direction along the first diagonal 24b of the thermoelectric element 24.

[0103] Note that the lensless region W1 on the rear surface of the lens array 3 can be embossed.

[0104] (1-10) Operation instructions of the human detection device

[0105] The human detection device 1 is installed on the ceiling of the warehouse in a state where the light-receiving surface 23a of the thermoelectric element 24 faces downward, for example. Thus, the human detection device 1 detects a person passing through a predetermined range (detection region R1) of the path located below it.

[0106] In the human detection device 1, when persons Q1a, Q1b move within the detection region R1, persons Q1a, Q1b move through at least one of all the effective regions r11 to r14 in the detection region R1 (i.e., the whole of the effective regions r11 to r14 where each individual detection region r1 includes four effective regions r11 to r14) (see Figure 3 andFigure 8 )。At this time, persons Q1a and Q1b move through the infrared reception path 70 corresponding to at least one effective area. When persons Q1a and Q1b move through the infrared reception path 70, the infrared radiation from persons Q1a and Q1b passes through the infrared reception path 70 and is received by one of the four detectors 242 of the thermoelectric element. When the level of the output signal of the thermoelectric element 24 exceeds the first threshold T1 or the second threshold T2 due to the reception of infrared radiation as described above, the determination unit 26 detects persons Q1a and Q1b.

[0107] More specifically, when person Q1a moves in the edge portions R11 (first detection areas) on both sides in the long side direction of the detection area R1, it is characterized in that, according to the moving speed V1 of person Q1a, the approaching component V11 is greater than the transverse component V12. Therefore, in the first detection areas R11 of the detection area R1, as described above, one of the four effective areas r11 to r14 in the individual detection area r1 in each edge portion R11 overlaps with one of the four effective areas r11 to r14 in the adjacent individual detection area r1. This overlap enables the human body detection device 1 to sensitively detect person Q1a moving in each of the first detection areas R11 at a moving speed with the approaching component V11 greater than the transverse component V12.

[0108] In addition, when person Q1b moves in the central portion R12 (second detection area) in the long side direction of the detection area R1, it is characterized in that, according to the moving speed V1 of person Q1b, the transverse component V12 is greater than the approaching component V11. Therefore, in the second detection area R12 of the detection area R1, as described above, the four effective areas r11 to r14 in the individual detection area r1 in the central portion R12 and the four effective areas r11 to r14 in the adjacent individual detection area r1 do not overlap with each other. Thus, the human body detection device 1 sensitively detects person Q1b moving in the second detection area R12 at a moving speed with the transverse component V12 greater than the approaching component V11.

[0109] (1-11) Main effects

[0110] The human body detection device 1 according to the present embodiment includes a thermoelectric element 24, a lens array 3, and a determination unit 26. The thermoelectric element 24 includes a plurality of detectors 242. The lens array 3 includes a plurality of lenses 311 configured to focus infrared radiation onto the thermoelectric element 24. The determination unit 26 outputs a human body detection signal based on the output signal of the thermoelectric element 24. Each of the plurality of lenses 311 and the plurality of detectors 242 define a plurality of infrared reception paths 70. The plurality of infrared reception paths 70 include a plurality of first infrared reception paths 70a and a plurality of second infrared reception paths 70b. The plurality of first infrared reception paths 70a are defined by any one of the plurality of lenses 311 and the plurality of detectors 242. The plurality of second infrared reception paths 70b are defined by one of the lenses 311 included in the plurality of lenses 311 and adjacent to the any one lens 311 and the plurality of detectors 242. The lens array 3 has a first region 95 and a second region 96. The first region 95 includes one or more first lenses 311p, 311q among the plurality of lenses 311. The second region 96 includes one or more second lenses 311w among the plurality of lenses 311. Each of the one or more first lenses 311p, 311q is one or more lenses such that, in each of the one or more lenses, one of the plurality of first infrared reception paths 70a defined by the corresponding first lens among the first lenses 311p, 311q and the plurality of detectors 242 of the thermoelectric element 24 and one of the plurality of second infrared reception paths 70b defined by one of the lenses 311 included in the plurality of lenses 311 and adjacent to the corresponding first lens among the one or more first lenses 311p, 311q and the plurality of detectors 242 overlap each other. Each of the one or more second lenses 311w is one or more lenses such that, in each of the one or more lenses, the plurality of first infrared reception paths 70a defined by the corresponding second lens among the one or more second lenses 311w and the plurality of detectors 242 of the thermoelectric element 24 and the plurality of second infrared reception paths 70b defined by one of the lenses 311 included in the plurality of lenses 311 and adjacent to the corresponding second lens among the one or more second lenses 311w and the plurality of detectors 242 do not overlap each other.

[0111] This configuration enables the detection area R1 of the human body detection device 1 to include a first detection area R11 corresponding to the first area 95 of the lens array 3 and a second detection area R12 corresponding to the second area 96 of the lens array 3. In each first detection area R11, as described above, one first infrared reception path 70a and one second infrared reception path 70b overlap each other, so that proximity detection can be performed sensitively. In the second detection area R12, as described above, the first infrared reception path 70a and the second infrared reception path 70b do not overlap each other, so that cross-cut detection can be performed sensitively. That is, in the detection area R1, both proximity detection and cross-cut detection can be performed sensitively.

[0112] (1-12) Variation

[0113] The variations of the embodiments will be described below. In the following description, components identical to those in the above embodiments are denoted by the same reference numerals as in the drawings of the present embodiment, and their descriptions may be omitted, and only the differences from the embodiments may be described.

[0114] (1-12-1) First variation

[0115] In the above embodiment, as Figure 10 shown, in the lens array 3, the first area 95 is arranged at the edge portion in the long side direction of the shape H1 of the lens configuration, and the second area 96 is arranged at the central portion of the shape H1 of the lens configuration in the lens array 3. However, the arrangements of the first area 95 and the second area 96 are not limited to the above examples, but the first area 95 and the second area 96 can be arranged at any part on the rear surface of the lens array 3 (more specifically, the rear surface of the lens array main body 31). In this case, it is desirable that the first area 95 be arranged closer to the outer periphery of the lens array 3 than the second area 96. In addition, the second area 96 is preferably arranged closer to the center of the lens array 3 than the first area 95.

[0116] (1-12-2) Second variation

[0117] In the above embodiment, the first area 95 of the lens array 3 is arranged at the edge portions on both sides in the long side direction of a plurality of lenses 311 (i.e., lens groups) (see Figure 10 ). However, in addition to or instead of the first area 95 of the embodiment, the first area 95 of the lens array 3 can be arranged at the edge portions on both sides in the short side direction of a plurality of lenses 311 (i.e., lens groups) (i.e., the portions adjacent to the lensless area W1).

[0118] (1-12-3) Third variation

[0119] As Figure 11As shown, the lens 311A arranged on the outer periphery of the plurality of lenses 311 of the lens array 3 in the above embodiment may be made into a Fresnel lens. More specifically, the serrated lens N0 included in the serrated lens portion of the Fresnel lens is arranged in the void space (i.e., the area where the lens 311 is not arranged) on the outer peripheral side of each lens 311A. For example, the serrated lens N1 having three protrusions is arranged on the upper side of the lens 311A-1, and the serrated lens N2 having one protrusion is arranged on the left side of the lens 311A-1. In addition, the serrated lens N3 having two protrusions is arranged on the left side of the lens 311A-2. Making the lens 311A into a Fresnel lens can collect more light.

[0120] (1-12-4) Fourth modification example

[0121] In the above embodiment, the first diagonal line 24b of the thermoelectric element 24 extends in the long side direction of the arrangement of the plurality of lenses 311 (lens group). Note that the second diagonal line 24c of the thermoelectric element 24 may extend in the long side direction of the arrangement of the plurality of lenses 311 (lens group).

[0122] (1-12-5) Fifth modification example

[0123] In the above embodiment, an example is shown in which the plurality of lenses 311 are arranged in a rectangular shape conforming to the shape (rectangular shape) of the detection region R1. However, the shape of the arrangement of the plurality of lenses 311 is not limited to a rectangular shape. For example, when the detection region R1 has a circular shape, the plurality of lenses 311 may be arranged in a circular shape.

[0124] (2) Aspects

[0125] Based on the embodiment and the modification examples, the present disclosure includes the following aspects.

[0126] The human body detection device (1) according to the first aspect includes a thermoelectric element (24), a lens array (3), and a determination unit (26). The thermoelectric element (24) includes a plurality of detectors (242). The lens array (3) includes a plurality of lenses (311) configured to focus infrared radiation onto the thermoelectric element (24). The determination unit (26) is configured to output a human body detection signal based on the output signal of the thermoelectric element (24). Each of the plurality of lenses (311) and the plurality of detectors (242) define a plurality of infrared reception paths (70). The plurality of infrared reception paths (70) include a plurality of first infrared reception paths (70a) and a plurality of second infrared reception paths (70b). The plurality of first infrared reception paths (70a) are defined by any one of the plurality of lenses (311) and the plurality of detectors (242). The plurality of second infrared reception paths (70b) are defined by one of the lenses (311) included in the plurality of lenses (311) and adjacent to the any one lens (311) and the plurality of detectors (242). The lens array (3) has a first region (95) and a second region (96). The first region (95) includes one or more first lenses (311p, 311q) among the plurality of lenses (311). The second region (96) includes one or more second lenses (311w) among the plurality of lenses (311). Each of the one or more first lenses (311p, 311q) is one or more lenses such that, in each of the one or more lenses, one of the plurality of first infrared reception paths (70a) defined by the corresponding first lens among the one or more first lenses (311p, 311q) and the plurality of detectors (242) and one of the plurality of second infrared reception paths (70b) defined by one of the lenses (311) included in the plurality of lenses (311) and adjacent to the corresponding first lens among the one or more first lenses (311p, 311q) and the plurality of detectors (242) overlap each other. Each of the one or more second lenses (311w) is one or more lenses such that, in each of the one or more lenses, the plurality of first infrared reception paths (70a) defined by the corresponding second lens among the one or more second lenses (311w) and the plurality of detectors (242) and the plurality of second infrared reception paths (70b) defined by one of the lenses (311) included in the plurality of lenses (311) and adjacent to the corresponding second lens among the one or more second lenses (311w) and the plurality of detectors (242) do not overlap each other.

[0127] This configuration enables the detection area (R1) of the human body detection device (1) to include: a first detection area (R11) corresponding to the first area (95) of the lens array (3); and a second detection area (R12) corresponding to the second area (96) of the lens array (3). In the first detection area (R11), as described above, a first infrared reception path (70a) and a second infrared reception path (70b) overlap each other, enabling proximity detection to be performed sensitively. In the second detection area (R12), as described above, the first infrared reception path (70a) and the second infrared reception path (70b) do not overlap each other, enabling cross-cut detection to be performed sensitively. That is to say, in the detection area (R1), both proximity detection and cross-cut detection can be performed sensitively.

[0128] In the human body detection device (1) according to the second aspect with reference to the first aspect, the plurality of detectors (242) include respective front-side electrodes (2421) and respective rear-side electrodes (2422). A first infrared reception path (70a) and a second infrared reception path (70b) that overlap each other correspond to respective detectors (242) included in the plurality of detectors (242) and having the same polarity for the front-side electrodes (2421).

[0129] This configuration enables the detection sensitivity of the human body detection device (1) to be improved.

[0130] In the human body detection device (1) according to a third aspect referring to the first aspect or the second aspect, the plurality of detectors (242) each include a front-side electrode (2421) and a rear-side electrode (2422). The thermoelectric element (24) is a four-element element including four detectors (242) as the plurality of detectors (242), and the four detectors (242) are arranged in a 2×2 array. The thermoelectric element (24) has a rectangular light-receiving surface (24a) including the front-side electrodes (2421) of the plurality of detectors (242) in the plan view of the thermoelectric element (24). Among the four detectors (242) arranged in a 2×2 array, two detectors (242) arranged in the direction along the first diagonal line (24b) of the rectangular light-receiving surface (24a) are connected in parallel with each other, two detectors (242) arranged in the direction along the second diagonal line (24c) of the rectangular light-receiving surface (24a) are connected in parallel with each other, two detectors (242) arranged in the row direction are connected in anti-parallel with each other, and two detectors (242) arranged in the column direction are connected in anti-parallel with each other. The front-side electrodes (2421) of the two detectors (242) arranged in the direction along the first diagonal line (24b) have the same polarity. The front-side electrodes (2421) of the two detectors (242) arranged in the row direction have different polarities. The front-side electrodes (2421) of the two detectors (242) arranged in the column direction have different polarities. One first infrared reception path (70a) and one second infrared reception path (70b) that overlap each other correspond to the respective detectors (242) included in the plurality of detectors (242) and are different from each other.

[0131] This configuration enables the detection sensitivity of the human body detection device (1) to be improved.

[0132] In the human body detection device (1) according to a fourth aspect referring to any one of the first aspect to the third aspect, in the lens array (3), the first region (95) is arranged closer to the outer periphery of the lens array (3) than the second region (96). In the lens array, the second region (96) is arranged closer to the center of the lens array (3) than the first region (95).

[0133] This configuration enables the first detection area (R11) corresponding to the first area (95) of the lens array (3) (i.e., the area where proximity detection can be performed sensitively) to be arranged on the outer peripheral side of the detection area (R1) of the human body detection device (1) (i.e., the area where the approach rate (V11) in the moving speed (V1) of a person is more likely to be higher than the transverse rate (V12)). This configuration also enables the second detection area (R12) corresponding to the second area (96) of the lens array (3) (i.e., the area where transverse detection can be performed sensitively) to be arranged on the central side of the detection area (R1) (i.e., in the area where the transverse component (V12) in the moving speed (V1) of a person is more likely to be greater than the approach component (V11)). This enables effective detection of a person moving at a moving speed (V1) with an approach component (V11) greater than the transverse component (V12) and a person moving at a moving speed (V1) with a transverse component (V12) greater than the approach component (V11) in the detection area (R1).

[0134] In the human body detection device (1) according to a fifth aspect with reference to any one of the first to fourth aspects, the plurality of detectors (242) are (N×N) detectors (242) configured in an N×N array, where N is an integer. Two diagonals in the N×N array configuration of the plurality of detectors (242) are defined as a first diagonal (24b) and a second diagonal (24c). The plurality of lenses (311) constitute a lens group in the lens array (3) including lens rows (311s) arranged in the direction along the first diagonal (24b).

[0135] This configuration enables the detection area (R1) of the human body detection device (1) to be formed in a shape extending in the direction along the first diagonal (24b). This configuration also enables the arrangement density of the lenses (311) to increase in the direction along the first diagonal (24b).

[0136] In the human body detection device (1) according to a sixth aspect with reference to the fifth aspect, the lens group in the lens array (3) includes a plurality of lens rows (311s) arranged in the direction along the second diagonal (24c).

[0137] This configuration also enables the detection area (R1) of the human body detection device (1) to be formed in a shape extending in the direction along the second diagonal (24c). This configuration also enables the arrangement density of the lenses (311) to increase in the direction along the second diagonal (24c).

[0138] In the human body detection device (1) according to a seventh aspect referring to the fifth or sixth aspect, the lens array (3) has a first part (M1) and a second part (M2). The first part (M1) is arranged on the outer peripheral end of the lens array (3). The second part (M2) is arranged on the outer peripheral end of the lens array (3) and faces the first part (M1) in a state where the center (CT1) of the lens array (3) is located between the second part (M2) and the first part (M1). The lens group is configured in the lens array (3) to have a band shape extending from the first part (M1) through the center (CT1) toward the second part (M2).

[0139] This configuration enables a detection region (R1) in a band shape to be formed as the detection region (R1) of the human body detection device (1).

[0140] In the human body detection device (1) according to an eighth aspect referring to any one of the fifth to seventh aspects, the lens array (3) has at least one lensless region (W1) where a plurality of lenses (311) are not arranged.

[0141] In this configuration, at least one lensless region (W1) is provided for the lens array (3), so that it is possible to form the detection region (R1) only in the region where human body detection is required in the place where the object to be sensed is located.

[0142] In the human body detection device (1) according to a ninth aspect referring to the eighth aspect, at least one lensless region (W1) includes a plurality of lensless regions arranged on each side of both sides of the lens group in the direction along the first diagonal (24b) or the second diagonal (24c).

[0143] This configuration enables non-detection regions to be arranged on both sides of the detection region (R1) in the direction along the first diagonal (24b) or the second diagonal (24c) of the thermoelectric element (24).

[0144] In the human body detection device (1) according to a tenth aspect referring to the eighth aspect, a first region (95) of the lens array (3) is arranged in the lens group such that the first region (95) is adjacent to at least one lensless region (W1).

[0145] This configuration enables a first detection region (R11) corresponding to the first region (95) of the lens array (3) to be arranged in the detection region (R1) such that the first detection region (R11) is adjacent to the non-detection region.

[0146] In the human body detection device (1) according to an eleventh aspect referring to any one of the fifth to tenth aspects, the first diagonal (24b) of the thermoelectric element (24) extends along the long side direction or the short side direction of the lens group configured in a band shape.

[0147] This configuration aligns the first diagonal line (24b) of the thermoelectric element (24) with the long side direction or the short side direction of the belt-shaped detection region (R1). This can increase the arrangement density of the lens (311), and as a result, can improve the detection sensitivity of the human body detection device (1).

[0148] List of Reference Numerals

[0149] 1 Human body detection device

[0150] 3 Lens array

[0151] 24 Electrothermal element

[0152] 24a Light-receiving surface

[0153] 24b First diagonal line

[0154] 24c Second diagonal line

[0155] 26 Judgment unit

[0156] 70 Infrared reception path

[0157] 70a First infrared reception path

[0158] 70b Second infrared reception path

[0159] 95 First region

[0160] 96 Second region

[0161] 242 Detector

[0162] 242A First detector

[0163] 232B Second detector

[0164] 2421 Front-side electrode

[0165] 2422 Rear-side electrode

[0166] 311 Lens

[0167] 311p, 311q First lens

[0168] 311s Lens row

[0169] 311w Second lens

[0170] CT1 Center

[0171] M1 First part

[0172] M2 Second part

[0173] R1 Detection region

[0174] R11 Edge part (first detection area)

[0175] R12 Central part (second detection area)

[0176] V1 Moving speed

[0177] V11 Approach rate

[0178] V12 Transverse cutting rate

[0179] W1 Lensless area

Claims

1. A human body detection device, comprising: A thermoelectric element, which includes a plurality of detectors; A lens array, which includes a plurality of lenses configured to focus infrared radiation onto the thermoelectric element; And A determination unit configured to output a human body detection signal based on an output signal of the thermoelectric element, wherein each of the plurality of lenses and the plurality of detectors is used to define a plurality of infrared reception paths, The plurality of infrared reception paths include: A plurality of first infrared reception paths defined by any one of the plurality of lenses and the plurality of detectors, and A plurality of second infrared reception paths defined by one lens included in the plurality of lenses and adjacent to the any one lens and the plurality of detectors, The lens array has: A first region, which includes one or more first lenses among the plurality of lenses, and A second region, which includes one or more second lenses among the plurality of lenses. Each of the one or more first lenses is one of the one or more lenses. In each of the one or more first lenses, one first infrared reception path among the plurality of first infrared reception paths defined by the corresponding first lens among the one or more first lenses and the plurality of detectors and one second infrared reception path among the plurality of second infrared reception paths defined by one lens included in the plurality of lenses and adjacent to the corresponding first lens among the one or more first lenses and the plurality of detectors overlap each other, and Each of the one or more second lenses is one of the one or more lenses. In each of the one or more second lenses, the plurality of first infrared reception paths defined by the corresponding second lens among the one or more second lenses and the plurality of detectors and the plurality of second infrared reception paths defined by one lens included in the plurality of lenses and adjacent to the corresponding second lens among the one or more second lenses and the plurality of detectors do not overlap each other.

2. The human body detection device according to claim 1, wherein The plurality of detectors include respective front-side electrodes and respective rear-side electrodes, and The one first infrared reception path and the one second infrared reception path that overlap each other correspond to respective detectors included in the plurality of detectors and having the same polarity of the front-side electrodes.

3. The human body detection device according to claim 1 or 2, wherein The plurality of detectors include respective front-side electrodes and respective rear-side electrodes, The thermoelectric element is a four-element element including four detectors as the plurality of detectors, and the four detectors are arranged in a 2×2 array, The thermoelectric element has a rectangular light-receiving surface including the respective front-side electrodes of the plurality of detectors in a plan view of the thermoelectric element, Among the four detectors arranged in a 2×2 array, Two detectors arranged in a direction along a first diagonal of the rectangular light-receiving surface are connected in parallel to each other, Two detectors arranged in the direction of the second diagonal of the rectangular light-receiving surface are connected in parallel with each other, two detectors arranged in the row direction are connected in anti-parallel with each other, and two detectors arranged in the column direction are connected in anti-parallel with each other, each front-side electrode of two detectors arranged in the direction of the first diagonal has the same polarity, each front-side electrode of two detectors arranged in the row direction has different polarities, and each front-side electrode of two detectors arranged in the column direction has different polarities, and the one first infrared reception path and the one second infrared reception path that overlap each other correspond to respective detectors included in the plurality of detectors and different from each other.

4. The human body detection device according to any one of claims 1 to 3, wherein, in the lens array, the first region is arranged closer to the outer periphery of the lens array than the second region, and in the lens array, the second region is arranged closer to the center of the lens array than the first region.

5. The human body detection device according to any one of claims 1 to 4, wherein, the plurality of detectors are (N×N) detectors configured in an N×N array, where N is an integer greater than or equal to 2, two diagonals in the N×N array configuration of the plurality of detectors are defined as the first diagonal and the second diagonal, and the plurality of lenses constitute a lens group including lens rows arranged in the direction of the first diagonal in the lens array.

6. The human body detection device according to claim 5, wherein, the lens group includes a plurality of lens rows arranged in the direction of the second diagonal in the lens array.

7. The human body detection device according to claim 5 or 6, wherein, the lens array has: a first part arranged at the outer peripheral end of the lens array, and a second part arranged at the outer peripheral end of the lens array and facing the first part in a state where the center of the lens array is located between the second part and the first part, and the lens group is configured in the lens array to have a band shape extending from the first part through the center toward the second part.

8. The human body detection device according to any one of claims 5 to 7, wherein, the lens array has at least one lensless region where a plurality of lenses are not arranged.

9. The human body detection device according to claim 8, wherein, the at least one lensless region includes a plurality of lensless regions arranged on each side of the lens group in the direction of the first diagonal or the second diagonal.

10. The human body detection device according to claim 8, wherein, the first region of the lens array is arranged in the lens group such that the first region is adjacent to the at least one lensless region.

11. The human body detection device according to any one of claims 5 to 10, wherein, the first diagonal of the thermoelectric element extends along the long side direction or the short side direction of the lens group configured in a band shape.

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