Detection sensor

Abstract

PURPOSE: To provide a detection sensor that can receive infrared rays and sound waves from the same direction and has a vibration membrane that is not exposed to the outside.CONSTITUTION: A detection sensor S1 includes a unit U and a holder H. The unit U includes a diaphragm 100 and a case 200 that houses the unit U. The case 200 has an opening 211 arranged on a Z-direction side of the diaphragm 100. The holder H includes a holding portion 10 that holds the unit U, a front portion 20 arranged on the Z-direction side of the case 200, a transmission portion 30 that can transmit infrared rays, a sound hole 40 that can input sound waves, and a sound path 50. The transmission portion 30 is provided in the front portion 20 and faces the diaphragm 100 on the Z-direction side of the opening 211 and the diaphragm 100. The sound hole 40 is provided in a portion around the transmission portion 30 of the front portion 20 and opens in the Z direction. The sound path 50 extends from the sound hole 40 to the opening 211.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] The present invention relates to a detection sensor. [Background technology]

[0002] The following Patent Document 1 describes a conventional first detection sensor. This first detection sensor includes a diaphragm made of a piezoelectric film, a case that houses the diaphragm, and a substrate. The diaphragm is configured to generate a first electric signal by pyroelectric effect when irradiated with infrared rays, and to generate a second electric signal by piezoelectric effect when vibrated by sound waves. The case has a transparent portion that is at least capable of transmitting infrared rays. This transparent portion is disposed on one side of the diaphragm in a first direction and faces the diaphragm. The first direction is the thickness direction of the diaphragm. The substrate is fixed to the case and disposed on the other side of the first direction with respect to the diaphragm. The substrate has a sound hole through which sound waves are input.

[0003] However, the first detection sensor is configured such that infrared rays are incident on the transmitting portion from one side in the first direction, while sound waves are input to the sound hole from the other side in the first direction. In other words, the first detection sensor is configured such that infrared rays and sound waves cannot be input from the same direction.

[0004] The following Patent Document 2 describes a conventional second detection sensor. This second detection sensor includes a shield case, a conductive support, and a polymeric piezoelectric film. The shield case has an opening that opens to one side in a first direction. The support is housed and held in the shield case and is disposed on the other side of the first direction with respect to the opening. The polymeric piezoelectric film is supported on the support and is disposed on the other side of the first direction with respect to the opening. The polymeric piezoelectric film is exposed to one side in the first direction from the opening. For this reason, infrared rays are irradiated from one side in the first direction through the opening to the polymeric piezoelectric film to generate a signal by the pyroelectric effect, and sound waves are input from one side in the first direction through the opening, and the polymeric piezoelectric film is vibrated by the sound waves to generate a signal. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2020-148018 A [Patent Document 2] Japanese Utility Model Application Publication No. 54-046525 Summary of the Invention [Problem to be solved by the invention]

[0006] In the second detection sensor, since the polymeric piezoelectric film is exposed from the opening, there is a risk that dust, dirt, water, and the like may adhere to the polymeric piezoelectric film.

[0007] The present invention provides a detection sensor that can receive infrared rays and sound waves from the same direction and has a vibration membrane that is not exposed to the outside. [Means for solving the problem]

[0008] A detection sensor according to an embodiment of the present invention includes a sensor unit and a holder. The sensor unit includes a vibration membrane made of a piezoelectric film and a case that houses the vibration membrane. The vibration membrane is configured to generate a first electric signal by a pyroelectric effect when irradiated with infrared rays, and to generate a second electric signal by a piezoelectric effect when vibrated by sound waves. The case has an opening arranged on one side in a first direction with respect to the vibration membrane. The first direction is a thickness direction of the vibration membrane. The holder includes a holding portion that holds the sensor unit, a front side portion that is arranged on one side in the first direction with respect to the case, a transmission portion that is capable of transmitting at least infrared rays, a sound hole through which sound waves can be input, and a sound path. The transmission portion is provided in the front side portion and is exposed from the front side portion to one side and the other in the first direction, and is arranged on one side in the first direction with respect to the opening and the vibration membrane and faces the vibration membrane. The sound hole is provided in a portion around the transmission portion of the front side portion and opens to one side in the first direction. The sound path extends from the sound hole to the opening of the case. Effect of the Invention

[0009] In the case of the detection sensor of the above-mentioned aspect, infrared rays and sound waves can be input from the same direction. The reason is as follows. The front part of the holder is arranged on one side in the first direction with respect to the case of the sensor unit. The transparent part of the holder is provided on the front part of the holder, exposed from the front part to one side in the first direction and the other side in the second direction, arranged on one side in the first direction with respect to the opening and the diaphragm of the sensor unit, and facing the diaphragm. Therefore, at least infrared rays are transmitted through the transparent part from one side in the first direction and irradiated onto the diaphragm of the sensor unit. In addition, since the sound hole is provided in the part around the transparent part of the front part and the sound path extends from the sound hole to the opening of the case, sound waves can also be input to the sound hole from one side in the first direction and vibrate the diaphragm through the sound hole, the sound path, and the opening. Furthermore, the transparent portion of the holder is provided on the front side of the holder and faces the vibrating membrane, while the sound hole is provided in the area around the transparent portion on the front side, so that the vibrating membrane is not exposed to the outside of the detection sensor through the sound hole, sound path and opening. [Brief description of the drawings]

[0010] [Figure 1A] 1 is a front, plan and right side perspective view of a detection sensor according to a first embodiment of the present invention; [Figure 1B] 2 is a rear, top, and left side perspective view of the detection sensor of the first embodiment. FIG. [Figure 2A] 2A is a cross-sectional view of the detection sensor of the first embodiment taken along line 2A-2A in FIG. 1A. [Figure 2B] 2B-2B cross-sectional view of the detection sensor of the first embodiment in FIG. 1A. [Figure 2C] 2C-2C cross-sectional view of the detection sensor of Example 1 in FIG. 2D. [Figure 2D] 2B is a cross-sectional view of the detection sensor of the first embodiment taken along line 2D-2D in FIG. 2A. [Figure 3A] 1 is an exploded perspective view of the detection sensor of the first embodiment, shown from the front, top and right side. FIG. [Figure 3B] 2 is an exploded perspective view of the detection sensor of the first embodiment as viewed from the rear, top and left side; FIG. [Figure 4] 1 is a block diagram of a detection device according to a first embodiment of the present invention. [Figure 5A] 2B is a cross-sectional view of a detection sensor according to a second embodiment of the present invention, corresponding to FIG. 2A. [Figure 5B] 2B is a cross-sectional view of the detection sensor according to the second embodiment, corresponding to FIG. 2B. [Figure 5C] FIG. 2D is a cross-sectional view of the detection sensor according to the second embodiment. [Figure 6A] 2B is a cross-sectional view of a detection sensor according to a third embodiment of the present invention, corresponding to FIG. 2A. [Figure 6B] 2B is a cross-sectional view of the detection sensor according to the third embodiment, which corresponds to FIG. 2B. [Figure 6C] FIG. 2D is a cross-sectional view of the detection sensor according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, a number of embodiments of the present invention, including embodiments 1 and 2 and their design variations, will be described. Note that the components of the embodiments and design variations described below can be combined with each other as long as they are not inconsistent. Note also that the materials, shapes, dimensions, numbers, arrangements, etc. constituting the components in each aspect of the embodiments and design variations described below are merely examples, and that the design can be changed as desired as long as the same functions can be realized. EXAMPLES

[0012] Hereinafter, a detection sensor S1 according to a first embodiment of the present invention and a number of other embodiments including its design variations will be described with reference to FIGS. 1A to 3B. FIGS. 1A to 3B show the detection sensor S1 of the first embodiment. FIGS. 1A to 2C and 3A to 3B show the Z-Z' direction (first direction). The Z-Z' direction includes the Z direction (one of the first directions) and the X' direction (the other of the first directions). FIGS. 1A to 2A and 2C to 3B show the Y-Y' direction (second direction). The Y-Y' direction is substantially perpendicular to the Z-Z' direction and includes the Y direction (one of the second directions) and the Y' direction (the other of the second directions). FIGS. 1A to 1B, 2B, 2D, and 3A to 3B show the X-X' direction (third direction). The XX' direction is approximately perpendicular to the ZZ' direction and the YY' direction, and includes the X direction (one of the third directions) and the X' direction (the other of the third directions).

[0013] The detection sensor S1 includes a sensor unit U (hereinafter, also simply referred to as "unit U"). The unit U includes a vibration membrane 100. The vibration membrane 100 is made of a piezoelectric film having pyroelectricity. The vibration membrane 100 includes a film body 110, a first electrode 120, and a second electrode 130. The film body 110 is, for example, a resin film (for example, a piezoelectric film) having a dimension (thickness dimension) in the Z-Z' direction of about 40 μm or 80 μm, and has a first surface on the Z-direction side and a second surface on the Z'-direction side. The first electrode 120 is provided on the first surface of the film body 110. The second electrode 130 is provided on the second surface of the film body 110. The Z-Z' direction is the thickness direction of the vibration membrane 100.

[0014] The diaphragm 100 is configured to generate a first electric signal by pyroelectric effect when irradiated with infrared rays. Specifically, the diaphragm 100 is spontaneously polarized when not irradiated with infrared rays. When the diaphragm 100 is irradiated with infrared rays, the spontaneous polarization state of the diaphragm 100 changes in response to the temperature change of the diaphragm 100 caused by the irradiation, and the voltage of the diaphragm 100 changes (i.e., the first electric signal is generated).

[0015] The diaphragm 100 is further configured to generate a second electric signal by the piezoelectric effect when vibrated by sound waves. Specifically, the diaphragm 100 is configured such that the voltage changes (i.e., the second electric signal is generated) in response to the distortion caused by the vibration.

[0016] The unit U further includes a case 200. The case 200 houses the diaphragm 100. The case 200 is made of a conductive material (for example, metal, etc.). The case 200 includes a top plate 210 and a tube portion 220. The top plate 210 is disposed on the Z direction side with respect to the diaphragm 100. The top plate 210 has an opening 211 penetrating the top plate 210 in the Z-Z' direction. The opening 211 is also disposed on the Z direction side with respect to the diaphragm 100. The tube portion 220 extends in the Z' direction from the periphery of the top plate 210. The tube portion 220 may include a locking portion 221. The locking portion 221 is an end portion of the tube portion 220 on the Z' direction side, and may be bent into a substantially L-shape or may extend in the Z-Z' direction. The locking portion 221 may be omitted. In this case, the tube portion 220 may be a tube with a bottom.

[0017] The unit U may further include a substrate 300. The substrate 300 is fixed to the case 200. For example, when the locking portion 221 is provided, the substrate 300 may be fixed to the locking portion 221 of the cylinder portion 220 of the case 200 that is bent into a substantially L-shape (see FIGS. 2A to 2C), or the locking portion 221 extending in the Z-Z' direction of the cylinder portion 220 of the case 200 may be inserted and held in an engagement hole of the substrate 300 (not shown), or the locking portion 221 of the cylinder portion 220 of the case 200 may be fixed by adhering it to the substrate 300 with a conductive adhesive or the like (not shown). When the locking portion 221 is not provided, the substrate 300 may be placed on the bottom of the cylinder portion 220 of the case 200. The substrate 300 is disposed at a distance from the vibration membrane 100 on the Z' direction side. The substrate 300 has a first surface on the Z direction side and a second surface on the Z' direction side. An electrode 310 for external connection is provided on the second surface of the substrate 300. The substrate 300 may be omitted.

[0018] The unit U may further include a field effect transistor 400 (hereinafter, also referred to as FET 400). The FET 400 is electrically connected to the diaphragm 100. The FET 400 is mounted on a substrate 300 (see FIGS. 2A to 2C). In FIGS. 3A and 3B, the FET 400 is omitted. The FET 400 is configured to perform impedance conversion on the first electric signal and / or the second electric signal input from the diaphragm 100 and output it as an output signal. When the output signal of the FET 400 is output to the outside of the detection sensor S1, the output signal of the FET 400 may be output from the electrode 310 of the substrate 300 to the outside of the detection sensor S1. The FET 400 may also be omitted. In this case, the FET 400 may be mounted on another substrate (not shown) outside the detection sensor S1 and electrically connected to the diaphragm 100.

[0019] The unit U may further include a conductive ring 500 and a cylindrical gate ring 600. The conductive ring 500 is interposed between the periphery of the diaphragm 100 and the top plate 210 of the case 200, and is in contact with the first electrode 120 of the diaphragm 100. In this case, the case 200 is made of a material having electrical conductivity. The gate ring 600 is conductive, is interposed between the periphery of the diaphragm 100 and the substrate 300, and is in contact with the second electrode 130 of the diaphragm 100. The first electrode 120 of the diaphragm 100 is electrically connected to the FET 400 via the conductive ring 500, the case 200, and the substrate 300, and the second electrode 130 of the diaphragm 100 is electrically connected to the FET 400 via the gate ring 600 and the substrate 300. In this manner, the FET 400 is electrically connected to the diaphragm 100.

[0020] The unit U may further include a cylindrical holder 700. The holder 700 is made of an electrically insulating material. The holder 700 is disposed between the gate ring 600 and the cylindrical portion 220 of the case 200. Therefore, the inner shape of the cross section of the holder 700 in the X-X' direction is the same as the outer shape of the cross section of the gate ring 600 in the X-X' direction, and the inner dimensions of the cross sections of the holder 700 along the Y-Y' direction and the X-X' direction are approximately the same as or slightly larger than the outer dimensions of the cross sections of the gate ring 600 along the Y-Y' direction and the X-X' direction. The outer shape of the cross section of the holder 700 along the Y-Y' direction and the X-X' direction is the same as the inner shape of the cross section of the tube part 220 of the case 200 along the Y-Y' direction and the X-X' direction, and the outer dimensions of the cross section of the holder 700 along the Y-Y' direction and the X-X' direction are approximately the same as or slightly smaller than the inner dimensions of the cross section of the tube part 220 of the case 200 along the Y-Y' direction and the X-X' direction. The holder 700 may be in contact with a portion of the vibrating membrane 100 that is outside the portion that the gate ring 600 contacts, but may not be in contact with the vibrating membrane 100. The holder 700 may be in contact with the substrate 300, but may not be in contact with the substrate 300. The holder 700 may be omitted.

[0021] The detection sensor S1 further includes a holder H. The holder H includes a holding portion 10 and a front portion 20.

[0022] The holding portion 10 holds the unit U. For example, the holding portion 10 is made of an insulating material (for example, insulating resin, etc.) and has any one of the following configurations (1) to (3).

[0023] (1) The holding portion 10 has a cylindrical portion 11 (see Figs. 1A to 3B). The cylindrical portion 11 has a cylindrical thin portion 11a and a cylindrical thick portion 11b. The thin portion 11a extends in the Z' direction from the front side portion 20. The thick portion 11b extends in the Z' direction from the thin portion 11a. The thickness dimension T1 of the thick portion 11b is larger than the thickness direction T2 of the thin portion 11a. The thick portion 11b of the cylindrical portion 11 fits onto the case 200 of the unit U and holds the unit U. In other words, the case 200 of the unit U fits (FIT IN) into the thick portion 11b and is held by the cylindrical portion 11. For this reason, the inner shapes of the cross sections of thick portion 11b taken along the Y-Y' direction and the X-X' direction are the same as the outer shapes of the cross sections of tubular portion 220 of case 200 taken along the Y-Y' direction and the X-X' direction, and the inner dimensions of the cross sections of thick portion 11b taken along the Y-Y' direction and the X-X' direction are approximately the same as or slightly smaller than the outer dimensions of the cross sections taken along the Y-Y' direction and the X-X' direction of tubular portion 220 of case 200. Hereinafter, the circumferential direction around the central axis of tubular portion 11 of retaining portion 10 will be referred to simply as the "circumferential direction".

[0024] (2) The holding portion 10 has a tubular portion 11, but the tubular portion 11 does not have a thin portion 11a and a thick portion 11b (not shown). The thickness dimension of the tubular portion 11 is approximately uniform from the end in the Z direction to the end in the Z' direction. The tubular portion 11 extends in the Z' direction from the front side portion 20. The tubular portion 11 fits onto the case 200 of the unit U and holds the unit U. In other words, the case 200 of the unit U fits (FIT IN) into the tubular portion 11 and is held by the tubular portion 11. Therefore, the inner shape of the cross section of tubular portion 11 along the Y-Y' direction and the X-X' direction is the same as the outer shape of the cross section of tubular portion 220 of case 200 along the Y-Y' direction and the X-X' direction, and the inner dimensions of the cross section of tubular portion 11 along the Y-Y' direction and the X-X' direction are approximately the same as or slightly smaller than the outer dimensions of the cross section of tubular portion 220 of case 200 along the Y-Y' direction and the X-X' direction.

[0025] (3) The holding portion 10 has a cylindrical portion 11 and a plurality of holding arms (not shown). The cylindrical portion 11 extends in the Z' direction from the front side portion 20. The plurality of holding arms extend in the Z' direction from the cylindrical portion 11 and are arranged at intervals in the circumferential direction. The plurality of holding arms elastically hold the case 200 of the unit U, and the top plate 210 of the case 200 of the unit U fits (FIT IN) into the cylindrical portion 11 and is held by the cylindrical portion 11.

[0026] The front side portion 20 may be made of an insulating material (e.g., insulating resin, etc.) and may be integrated with the holding portion 10, but is not limited thereto. The front side portion 20 is disposed on the Z direction side with respect to the case 200 of the unit U. For example, the front side portion 20 may be disposed facing the case 200 of the unit U with a gap G on the Z direction side. When the holding portion 10 has the above-mentioned configuration (1), the front side portion 20, the top plate 210 of the case 200, and the thin-walled portion 11a of the holding portion 10 define the gap G. When the holding portion 10 has the above-mentioned configuration (2) or (3), the front side portion 20, the top plate 210 of the case 200, and the tube portion 11 of the holding portion 10 define the gap G. In either case, the gap G exists between the front side portion 20 and the case 200 of the unit U and communicates with the opening 211 of the case 200.

[0027] The front side portion 20 may or may not have a retaining hole 21. The retaining hole 21 has the following configuration (4) or (5).

[0028] (4) The retaining hole 21 has a first hole 21a and a second hole 21b. The first hole 21a opens in the Z direction, and the second hole 21b is located on the Z' direction side of the first hole 21a, communicates with the first hole 21a, and opens in the Z' direction. The cross-sectional shapes of the second hole 21b along the Y-Y' direction and the X-X' direction may be the same as or different from the cross-sectional shapes of the first hole 21a along the Y-Y' direction and the X-X' direction. The cross-sectional dimensions of the second hole 21b along the Y-Y' direction and the X-X' direction are smaller than the cross-sectional dimensions of the first hole 21a along the Y-Y' direction and the X-X' direction.

[0029] (5) Retaining hole 21 is a through hole that penetrates front portion 20 in the Z-Z' direction, and the cross-sectional dimensions of retaining hole 21 along the Y-Y' direction and the X-X' direction are approximately the same from the Z-direction end of retaining hole 21 to the Z'-direction end of retaining hole 21.

[0030] The holder H or the case 200 may further include at least one stopper 60. The at least one stopper 60 may be one or more.

[0031] When one or more stoppers 60 are provided on the holder H, the one or more stoppers 60 are made of an insulating material (for example, insulating resin, etc.) and are provided on the front side portion 20 or the holding portion 10. When one or more stoppers 60 are provided on the front side portion 20, the one or more stoppers 60 are protruding portions extending from the front side portion 20 in the Z' direction (see Figs. 2A to 2D). When one or more stoppers 60 are provided on the holding portion 10 (not shown), the one or more stoppers 60 are protruding portions extending from any of the above-mentioned (1) to (3) tube portions 11 of the holding portion 10 toward the central axis of the tube portion 11. In either case, the one or more stoppers 60 are disposed on the Z' direction side with respect to the front side portion 20. The one or more stoppers 60 abut against the top plate 210 of the case 200 of the unit U from the Z direction side. This ensures a gap G between the front portion 20 and the case 200 of the unit U.

[0032] When one or more stoppers 60 are provided on the case 200, the one or more stoppers 60 are protrusions extending in the Z direction from the top plate 210 of the case 200. The one or more stoppers 60 abut against the front side portion 20 from the Z' direction side. This ensures a gap G between the front side portion 20 and the case 200 of the unit U.

[0033] At least one of the stoppers 60 may be omitted. In this case, the unit U is positioned by being held by the holding portion 10 in any of the above-described manners, and the gap G between the front portion 20 and the case 200 of the unit U is secured.

[0034] The holder H further includes a transmission section 30. The transmission section 30 is configured to transmit at least infrared light. The transmission section 30 may have an optical filter that transmits infrared light. The optical filter may be configured to transmit infrared light in a predetermined wavelength band. For example, the optical filter may be configured to transmit infrared light in a wavelength band of about 0.7 μm to 14 μm, or may be configured to transmit infrared light and light in a wavelength band nearby the infrared light (for example, visible light in a wavelength band of about 0.4 μm to 0.78 μm and / or microwaves in a wavelength band of 1 mm to 1 m). The optical filter may be configured as an optical lens made of silicon or the like. The thickness dimension (dimension in the Z-Z' direction) of the optical filter may be 0.55 mm ± 0.05 mm, and the average transmittance of light having a wavelength range of 7 μm to 14 μm at an incident angle of about 10 degrees to 20 degrees of the optical filter may be 70% or more, but is not limited thereto.

[0035] The transmission section 30 can be configured to have a transmission section main body 31 and an outer peripheral section 32 around the transmission section main body 31. The transmission section main body 31 may be configured from the optical filter, and the outer peripheral section 32 may be configured from a resin molded around the transmission section main body 31. Alternatively, the transmission section main body 31 may be configured from the center of the optical filter, and the outer peripheral section 32 may be configured from the outer peripheral section of the optical filter. Printing, masking, or the like may be applied to the latter outer peripheral section 32, but it does not have to be applied thereto.

[0036] The transmission section body 31 of the transmission section 30 may be made of a transparent or translucent resin or glass that can transmit at least infrared rays, instead of the optical filter. The entire transmission section 30 may be made of the resin or glass.

[0037] The transmission portion 30 is provided on the front side portion 20 of the holder H. For example, the transmission portion 30 is provided on the front side portion 20 of the holder H as in any one of the following (6) to (8).

[0038] When the retaining hole 21 is provided in the front side portion 20 and has the configuration of (4) above, (6) the transmissive portion 30 is accommodated and retained in the first hole 21a of the retaining hole 21 in the front side portion 20. The outer shape of the cross section of the transmissive portion 30 along the Y-Y' direction and the X-X' direction is approximately the same as the shape of the cross section of the first hole 21a along the Y-Y' direction and the X-X' direction, and the outer dimensions of the cross section of the transmissive portion 30 along the Y-Y' direction and the X-X' direction are approximately the same as or slightly smaller than the dimensions of the cross section of the first hole 21a along the Y-Y' direction and the X-X' direction. In this case, the transmissive portion 30 is exposed in the Z direction from the first hole 21a of the front side portion 20. The transmitting portion 30 is exposed in the Z' direction from the second hole 21b of the retaining hole 21 of the front portion 20, and is disposed on the Z direction side with respect to the second hole 21b, the gap G, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. Therefore, infrared rays are transmitted through the transmitting portion 30 from the Z direction side and irradiated onto the diaphragm 100.

[0039] When the holding hole 21 is provided in the front side portion 20 and has the configuration of (5), (7) the transmission portion 30 is accommodated and held in the holding hole 21 of the front side portion 20. The outer shape of the cross section of the transmission portion 30 along the Y-Y' direction and the X-X' direction is approximately the same as the shape of the cross section of the holding hole 21 along the Y-Y' direction and the X-X' direction, and the outer dimensions of the cross section of the transmission portion 30 along the Y-Y' direction and the X-X' direction are approximately the same as or slightly smaller than the dimensions of the cross section of the holding hole 21 along the Y-Y' direction and the X-X' direction. In this case, the transmission portion 30 is exposed in the Z direction and the Z' direction from the holding hole 21 of the front side portion 20, and is disposed on the Z direction side with respect to the gap G, the opening 211 of the case 200 of the unit U, and the vibration membrane 100, and faces the vibration membrane 100. Therefore, infrared rays are transmitted through the transmission portion 30 from the Z direction side and irradiated to the vibration membrane 100.

[0040] When the holding hole 21 is not provided in the front side portion 20, (8) the transmitting portion 30 is embedded in the front side portion 20 of the holder H by insert molding or the like. In this case, the transmitting portion 30 is exposed in the Z direction and the Z' direction from the front side portion 20, and is disposed on the Z direction side with respect to the gap G, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. Therefore, infrared rays are transmitted through the transmitting portion 30 from the Z direction side and irradiated onto the diaphragm 100.

[0041] The holder H further includes at least one sound hole 40 through which sound waves can be input. When there is one at least one sound hole 40, the one sound hole 40 is provided in the portion around the transparent portion 30 of the front side portion 20. When there is a plurality of at least one sound hole 40, the plurality of sound holes 40 are provided in the portion around the transparent portion 30 of the front side portion 20 and are arranged at intervals along the circumferential direction. The one or more sound holes 40 penetrate the portion around the transparent portion 30 of the front side portion 20 in the Z-Z' direction, open in both the Z direction and the Z' direction, and communicate with the gap G. Therefore, the one or more sound holes 40 allow sound waves to be input from the Z direction side.

[0042] When the holding part 10 has the above configuration (1), the one or more sound holes 40 face the tube part 11 of the holding part 10 and / or the top plate 210 (peripheral part of the opening 211) of the case 200 of the unit U through the gap G, but do not face the opening 211 and the diaphragm 100 of the case 200 of the unit U. When the holding part 10 has the above configuration (2) or (3), the one or more sound holes 40 face the top plate 210 (peripheral part of the opening 211) of the case 200 of the unit U through the gap G, but do not face the opening 211 and the diaphragm 100 of the case 200 of the unit U. In either case, the diaphragm 100 is not exposed to the outside of the holder H through the opening 211, the gap G, and the one or more sound holes 40 of the case 200.

[0043] The holder H further includes a sound path 50. The sound path 50 has a gap G. The gap G exists between the front side portion 20 of the holder H and the case 200 of the unit U, and forms a sound path extending from one or more sound holes 40 to an opening 211 of the case 200. Sound waves input from one or more sound holes 40 pass through the gap G (sound path) and the opening 211 of the case 200 of the unit U to vibrate the diaphragm 100.

[0044] The detection sensor S1 may further include a cover C through which sound waves can pass. The cover C may be made of cloth or may be made of a waterproof and / or dustproof sheet (not shown). When there is at least one sound hole 40, the cover C is provided on a portion around the transparent portion 30 of the front part 20 of the holder H and covers the one sound hole 40 from the Z direction side. When there are at least one sound hole 40, the cover C is ring-shaped and provided on a portion around the transparent portion 30 of the front part 20 of the holder H and covers the multiple sound holes 40 from the Z direction side. The cover C can be omitted. Even in this case, the one or more sound holes 40 are not exposed to the outside of the holder H through the gap G and the one or more sound holes 40 as described above.

[0045] Hereinafter, a detailed description will be given of a method for incorporating the unit U into the holder H. First, the unit U and the holder H are prepared. The front part 20 of the prepared holder H is provided with the transmission part 30 in any of the above-described manner.

[0046] When the holding portion 10 of the holder H has the above-mentioned configuration (1), the unit U is fitted into the thick portion 11b of the holding portion 10 of the holder H from the Z' direction. When the holder H is provided with one or more stoppers 60, the one or more stoppers 60 abut against the top plate 210 of the case 200 of the unit U. At this time, a gap G is defined by the front side portion 20 of the holder H, the tube portion 11, and the top plate 210 of the case 200, and the transmitting portion 30 of the holder H faces the diaphragm 100 of the unit U through the gap G and the opening 211 of the top plate 210 of the case 200, and one or more sound holes 40 of the holder H faces the thick portion 11b of the holding portion 10 and / or the top plate 210 of the case 200 (the peripheral portion of the opening 211) through the gap G. When the holder H is not provided with one or more stoppers 60, the unit U fits into the thick portion 11b of the holding portion 10 of the holder H from the Z' direction, and as described above, a gap G is defined, the transmitting portion 30 of the holder H faces the diaphragm 100 of the unit U, and one or more sound holes 40 of the holder H faces the thick portion 11b of the holding portion 10 and / or the top plate 210 of the case 200. In this manner, the unit U is held in the holding portion 10 of the holder H.

[0047] When the holding portion 10 of the holder H has the above configuration (2), the unit U is fitted into the tubular portion 11 of the holding portion 10 of the holder H from the Z' direction. As a result, the unit U is held by the holding portion 10 of the holder H in the same manner as when the holding portion 10 of the holder H has the above configuration (1) and is provided with one or more stoppers 60, or when the holding portion 10 of the holder H has the above configuration (1) and is not provided with one or more stoppers 60.

[0048] When the holding portion 10 of the holder H has the above configuration (3), the unit U is held by a plurality of holding arms of the holding portion 10 of the holder H. This allows the unit U to be held by the holding portion 10 of the holder H in the same manner as when the holding portion 10 of the holder H has the above configuration (1) and is provided with one or more stoppers 60, or when the holding portion 10 of the holder H has the above configuration (1) and is not provided with one or more stoppers 60.

[0049] A detection device D according to a number of embodiments including a first embodiment of the present invention will be described below with reference to Fig. 4. Fig. 4 shows the detection device D according to the first embodiment.

[0050] The detection device D can be configured to include the detection sensor S1 according to any of the above aspects, a low-pass filter F1, and a high-pass filter F2.

[0051] The low-pass filter F1 is electrically connected to the FET 400 and receives an output signal from the FET 400. The low-pass filter F1 may be provided on a substrate (not shown) electrically connected to the substrate 300, or may be provided on the substrate 300. The low-pass filter F1 is configured to pass signals in a frequency band obtained by impedance conversion from the first electrical signal among the input output signals, while attenuating signals in a frequency band higher than the frequency band of the signal passing through the low-pass filter F1. Specifically, since the signal obtained by impedance conversion from the first electrical signal has a frequency band of 0.35 Hz to 5.0 Hz, the low-pass filter F1 is configured to pass signals in a frequency band of 10 Hz and lower among the input output signals, while attenuating signals in a frequency band higher than 10 Hz (excluding 10 Hz).

[0052] The high-pass filter F2 is electrically connected to the FET 400 and receives an output signal from the FET 400. The high-pass filter F2 may be provided on a substrate (not shown) electrically connected to the substrate 300, or may be provided on the substrate 300. The high-pass filter F2 is configured to pass signals in a frequency band higher than the frequency band of signals passing through the low-pass filter F1 among the input output signals, while attenuating signals in a frequency band lower than the frequency band of signals passing through the high-pass filter F2. For example, the high-pass filter F2 is configured to pass signals in a frequency band of 200 Hz to 300 Hz, while attenuating signals in a frequency band of 200 Hz and lower.

[0053] The detection device D may further include a control unit CE. The control unit CE may be provided on a substrate (not shown) electrically connected to the substrate 300, or may be provided on the substrate 300. The control unit CE is electrically connected to the low-pass filter F1 and the high-pass filter F2, respectively. The control unit CE is configured to receive signals that have passed through the low-pass filter F1 and the high-pass filter F2. The control unit CE may be electrically connected to the FET 400 and receive an output signal from the FET 400, but is not limited to this.

[0054] The control unit CE may have a configuration for determining whether or not a signal is input only from the low-pass filter F1. A non-limiting example of the configuration of the control unit CE will be described below. The control unit CE determines whether or not a signal is input from the low-pass filter F1 (first determination). When the control unit CE determines that a signal is input from the low-pass filter F1, the control unit CE counts a predetermined period using a timer circuit inside the control unit CE or a software timer on an internal memory, and determines whether or not a signal is input from the high-pass filter F2 within the predetermined period (second determination). When the control unit CE determines that a signal is input from the high-pass filter F2 within the predetermined period (i.e., when it determines that a signal is not input only from the low-pass filter F1), the control unit CE returns to the first determination process. On the other hand, when the control unit CE determines that a signal is not input from the high-pass filter F2 within the predetermined period, it determines that a signal is input only from the low-pass filter F1. Note that the control unit CE may be configured to perform the first determination within the predetermined period after performing the second determination, rather than performing the second determination within the predetermined period after performing the first determination.

[0055] When the control unit CE determines that a signal is input only from the low-pass filter F1, this means that only a signal that has been impedance-converted from the first electric signal generated from the diaphragm 100 due to irradiation of infrared rays is input, and therefore the control unit CE determines that infrared rays are hitting the diaphragm 100. This allows the control unit CE to detect infrared rays. When the control unit CE determines that a signal is not input only from the low-pass filter F1, this means that a signal that has been impedance-converted from the second electric signal generated from the diaphragm 100 that vibrates due to sound waves is input, and therefore the control unit CE determines that the diaphragm 100 is vibrating due to sound waves. In this way, the control unit CE can detect sound waves.

[0056] The control unit CE may further have a configuration for performing signal processing such as voice recognition processing on the signal input from FET 400 when it is determined that a signal is input only from low-pass filter F1, or a configuration for performing signal processing such as voice recognition processing on the signal input from low-pass filter F1 and high-pass filter F2. The control unit CE may also be configured to amplify the signal input from FET 400 or the signal input from low-pass filter F1 and high-pass filter F2, and perform the above-mentioned signal processing on the amplified signal.

[0057] The control unit CE may be configured to return to the first judgment based on instruction information from the outside. Alternatively, when the control unit CE judges that a signal is input only from the low-pass filter F1, the control unit CE may be configured to count a predetermined period using an internal timer circuit of the control unit CE or a software timer in an internal memory, and perform any of the above-mentioned signal processing within the predetermined period. The control unit CE may be configured to return to the first judgment processing after the predetermined period has elapsed. The control unit CE may be configured to omit the configuration for performing the signal processing and to repeat the first judgment and second judgment processing in this order or in the reverse order.

[0058] Generally, infrared rays having a peak wavelength of about 10 μm (1000 nm) are emitted from a human body, and the infrared rays are transmitted through the transmitting portion 30 of the detection sensor S1 and irradiated to the vibration membrane 100, so that the approach of a human body (including the act of holding a hand over the detection sensor S1) is detected by the detection device D as described above. When the detection device D is built into a trash can, for example, the detection device D can be configured to detect the approach of a human body by irradiating the vibration membrane 100 with infrared rays as described above, and to perform voice recognition processing of the voice input to the detection sensor S1. In this case, the trash can can be configured to open and close its lid in response to either the approach of a person or the detection of a voice. When the detection device D is built into furniture, electrical appliances, etc., the furniture, electrical appliances, etc. can be operated in response to either the approach of a person or the detection of a voice, just like the trash can. When the detection device D is built into a vending machine or a ticket vending machine, for example, the detection device D can be configured to detect the approach of a human body by irradiating the vibration membrane 100 with infrared rays, as described above, and then perform voice recognition processing of the voice input to the detection sensor S1. In this case, after the vending machine or ticket vending machine detects the approach of a person, the human body can purchase a product by voice without touching the vending machine or ticket vending machine. When the detection device D is built into a fire detector, for example, the detection device D can be configured to detect a temperature change such as a fire by irradiating the vibration membrane 100 with infrared rays, as described above, and then perform voice recognition processing of the voice input to the detection sensor S1. In this case, the fire detector can transmit the processed voice data through a line such as the Internet after detecting the temperature change such as a fire. The fire detector may also be configured to turn on an alarm buzzer or the like by detecting a temperature change such as a fire. When the detection device D is built into an alarm device such as a security camera, for example, the detection device D can be configured to perform voice recognition processing after detecting the approach of a human body by irradiating infrared rays onto the diaphragm 100 as described above. In this case, after detecting the approach of a person, the alarm device can record the processed voice data (voice, sounds, etc.) or transmit it via a line such as the Internet.

[0059] The above-described detection sensor S1 provides the following technical features and advantages (1) to (5).

[0060] Technical Features and Effects (1) The detection sensor S1 can receive infrared rays and sound waves from the same direction (Z direction). The reason is as follows. The front side part 20 of the holder H is disposed on the Z direction side with respect to the case 200 of the unit U. The transparent part 30 of the holder H is provided on the front side part 20, is exposed from the front side part 20 in the Z direction and the Z' direction, and faces the vibration membrane 100 through the opening 211 of the case 200. Therefore, at least infrared rays pass through the transparent part 30 of the holder H from the Z direction side and are irradiated to the vibration membrane 100. In addition, at least one sound hole 40 is provided in a portion around the transparent part 30 of the front side part 20 of the holder H, opens in the Z direction, and communicates with the gap G. The gap G communicates with the opening 211 of the case 200. Therefore, sound waves can also be input to at least one sound hole 40 from the Z direction side, pass through at least one sound hole 40, the gap G, and the opening 211, and vibrate the vibration membrane 100.

[0061] Technical Features and Effects (2) The vibration membrane 100 is not exposed to the outside of the detection sensor S1. The reason is as follows. The transparent portion 30 of the holder H is provided on the front side portion 20 and faces the vibration membrane 100 through the opening 211 of the case 200. At least one sound hole 40 is provided in a portion around the transparent portion 30 of the front side portion 20 of the holder H. Therefore, the vibration membrane 100 is not exposed to the outside of the detection sensor S1 through at least one sound hole 40, the sound path 50 (gap G) and the opening 211. Therefore, the possibility that dust, dirt, water, etc. (hereinafter, these are collectively referred to as "dust, etc.") enters the detection sensor S1 through at least one sound hole 40 and the gap G and adheres to the vibration membrane 100 is reduced. In addition, when the cover C is provided, at least one sound hole 40 is blocked by the cover C, so that the possibility that dust, etc. enters the detection sensor S1 through at least one sound hole 40 and the gap G and adheres to the vibration membrane 100 is further reduced.

[0062] Technical Features and Effects (3) By changing the number and / or dimensions of at least one sound hole 40 of the detection sensor S1, the frequency characteristics of the high frequency band (e.g., 3 kHz to 20 kHz) of the sound waves input into the detection sensor S1 from the at least one sound hole 40 can be adjusted.

[0063] Technical features and effects (4) Since the unit U is held by the holding part 10 of the holder H, the holding position of the holding part 10 with respect to the unit U can be set arbitrarily. By changing the holding position of the holding part 10 with respect to the unit U, the linear distance in the Z-Z' direction between the transmission part 30 of the holder H and the vibration membrane 100 of the unit U held by the holding part 10 of the holder H can be changed, so that the sensor sensitivity of the detection sensor S1 to infrared rays can be changed. Moreover, by changing the holding position of the holding part 10 with respect to the unit U and increasing the linear distance, the incident angle of the infrared rays with respect to the vibration membrane 100 of the detection sensor S1 can also be increased. The incident angle is the angle between a line perpendicular to the surface of the vibration membrane 100 of the detection sensor S1 (normal line) and the infrared rays incident on the vibration membrane 100 of the detection sensor S1.

[0064] Technical Features and Effects (5) The versatility of the detection sensor S1 is improved for the following reasons: As described above, in the detection sensor S1, the vibration membrane 100 is not exposed to the outside of the detection sensor S1, so that the detection sensor S1 can be installed in a place with a lot of dust and / or a place where water may adhere.

[0065] Since the detection device D includes the detection sensor S1, the detection device D also has the above technical features and effects (1) to (5). EXAMPLES

[0066] Hereinafter, a detection sensor S2 (not shown) according to a plurality of embodiments including a second embodiment and its design variations of the present invention will be described with reference to Figs. 5A to 5C. Figs. 5A to 5C show the detection sensor S2 of the second embodiment. The detection sensor S2 has the same configuration as the detection sensor S1 described above, except that the front part 20 of the holder H of the detection sensor S2 directly abuts against the top plate 210 of the case 200 of the unit U and at least one sound hole 40 and sound path 50 of the holder H are different in configuration from at least one sound hole 40 and sound path 50 of the holder H of the detection sensor S1. Hereinafter, only the differences will be described in detail, and overlapping descriptions will be omitted. In Fig. 5A, the Z-Z' direction and the Y-Y' direction are shown in the same way as Fig. 2A. In Fig. 5B, the Z-Z' direction and the X-X' direction are shown in the same way as Fig. 2B. In Fig. 5C, the Y-Y' direction and the X-X' direction are shown in the same way as Fig. 2D.

[0067] The holding portion 10 of the holder H can have any one of the above configurations (1) to (3). In Figs. 5A to 5C, the holding portion 10 of the holder H has the above configuration (2).

[0068] The front side portion 20 of the holder H of the detection sensor S2 directly contacts the top plate 210 of the case 200 of the unit U. There is no gap G between the front side portion 20 of the holder H and the top plate 210 of the case 200, and at least one stopper 60 is not provided on the detection sensor S2.

[0069] When the holding hole 21 is provided in the front side portion 20 and has the configuration of (4) above, (9) the second hole 21b of the holding hole 21 in the front side portion 20 extends from the first hole 21a to the opening 211 of the case 200 of the unit U (see Figs. 5A to 5C). In this case, the transmission portion 30 is exposed in the Z direction from the first hole 21a of the holding hole 21 in the front side portion 20. In addition, the transmission portion 30 is exposed in the Z' direction from the second hole 21b of the holding hole 21 in the front side portion 20, and is disposed on the Z direction side with respect to the second hole 21b, the opening 211 of the case 200 of the unit U, and the vibration membrane 100, and faces the vibration membrane 100. Therefore, infrared rays are transmitted through the transmission portion 30 from the Z direction side and irradiated to the vibration membrane 100.

[0070] When the retaining hole 21 is provided in the front side portion 20 and has the configuration of (5) above, (10) a hole portion (not shown) is provided in the Z'-direction side of the retaining hole 21 in the front side portion 20, extending from the retaining hole 21 to the opening 211 of the case 200 of the unit U. In this case, the transmitting portion 30 is exposed in the Z-direction from the retaining hole 21 in the front side portion 20 and exposed in the Z'-direction from the hole portion in the front side portion 20, and is disposed on the Z-direction side with respect to the hole portion, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. Therefore, infrared rays are transmitted through the transmitting portion 30 from the Z-direction side and irradiated to the diaphragm 100.

[0071] In the case where the retaining hole 21 is not provided in the front side portion 20, (11) a hole portion (not shown) is provided in the front side portion 20 extending from the transmitting portion 30 to the opening 211 of the case 200 of the unit U. In this case, the transmitting portion 30 is exposed in the Z direction from the front side portion 20 and exposed in the Z' direction from the hole portion of the front side portion 20, and is disposed on the Z direction side with respect to the hole portion, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. Therefore, infrared rays are transmitted through the transmitting portion 30 from the Z direction side and irradiated to the diaphragm 100.

[0072] At least one sound hole 40 and sound path 50 of the holder H of the detection sensor S2 are provided in the portion around the transmission portion 30 of the front side portion 20.

[0073] The one or more sound holes 40 of the holder H of the detection sensor S2 have substantially the same configuration as the one or more sound holes 40 of the holder H of the detection sensor S1, except that the one or more sound holes 40 are holes that do not penetrate the portion around the transparent portion 30 of the front portion 20 in the Z-Z' direction. The one or more sound holes 40 of the holder H of the detection sensor S2 are open on the Z direction side, allowing sound waves to be input from the Z direction side.

[0074] The sound path 50 of the holder H of the detection sensor S2 extends from one or more sound holes 40 to the opening 211 of the case 200 and communicates with one or more sound holes 40 and the opening 211. For example, the sound path 50 can be configured to have one or more recesses 51 and the second hole 21b of (9), the hole portion of (10), or the hole portion of (11), or to have one or more horizontal holes (not shown) and the second hole 21b of (9), the hole portion of (10), or the hole portion of (11). The one or more recesses 51 extend from one or more sound holes 40 to the second hole 21b of (9), the hole portion of (10), or the hole portion of (11), and extend from one or more sound holes 40 in the Z' direction and open in the Z' direction. The one or more horizontal holes extend from the one or more sound holes 40 to the second hole 21b (9), the hole (10), or the hole (11). Sound waves input from the one or more sound holes 40 pass through the sound path 50 in the front side portion 20 and the opening 211 in the case 200 of the unit U, causing the diaphragm 100 to vibrate.

[0075] When the sound path 50 has one or more recesses 51 and the holding portion 10 has the above configuration (1), the one or more sound holes 40 face the tube portion 11 of the holding portion 10 and / or the top plate 210 of the case 200 of the unit U through one or more recesses 51 of the sound path 50, but do not face the opening 211 of the case 200 of the unit U and the vibration membrane 100 through one or more recesses 51 of the sound path 50. When the sound path 50 has one or more recesses 51 and the holding portion 10 has the above configuration (2) or (3), the one or more sound holes 40 face the top plate 210 of the case 200 of the unit U through one or more recesses 51 of the sound path 50, but do not face the opening 211 of the case 200 of the unit U and the vibration membrane 100 through one or more recesses 51 of the sound path 50. In either case, the diaphragm 100 is not exposed to the outside of the holder H through the opening 211 of the case 200 , the sound path 50 , and the one or more sound holes 40 .

[0076] When the sound path 50 has one or more horizontal holes, the one or more sound holes 40 face the bottom of the one or more horizontal holes of the sound path 50, and therefore do not face the opening 211 of the case 200 of the unit U and the vibration membrane 100.

[0077] The detection device D of the second embodiment has the same configuration as the detection device D of the first embodiment, except that the detection device D includes a detection sensor S2 of any of the above aspects instead of the detection sensor S1 of any of the above aspects.

[0078] The above-described detection sensor S2 provides the following technical features and advantages (1) and (2).

[0079] Technical Features and Effects (1) The detection sensor S2 can receive infrared rays and sound waves from the same direction. The reason is as follows. The front side portion 20 of the holder H is disposed on the Z direction side with respect to the case 200 of the unit U. The transparent portion 30 of the holder H is provided on the front side portion 20, is exposed from the front side portion 20 in the Z direction and the Z' direction, and faces the vibration membrane 100 through the opening 211 of the case 200. Therefore, at least infrared rays pass through the transparent portion 30 of the holder H from the Z direction side and are irradiated to the vibration membrane 100. In addition, at least one sound hole 40 is provided in a portion around the transparent portion 30 of the front side portion 20 of the holder H and opens in the Z direction. The sound path 50 is provided on the front side portion 20 and extends from the at least one sound hole 40 to the opening 211 of the case 200. Therefore, sound waves can also be input to at least one sound hole 40 from the Z direction side, pass through at least one sound hole 40, the sound path 50, and the opening 211, and vibrate the diaphragm 100.

[0080] Technical Features and Effects (2) The vibration membrane 100 is not exposed to the outside of the detection sensor S2. The transparent portion 30 of the holder H is provided on the front side portion 20 and faces the vibration membrane 100 through the opening 211 of the case 200. At least one sound hole 40 is provided in a portion around the transparent portion 30 of the front side portion 20 of the holder H. Therefore, the vibration membrane 100 is not exposed to the outside of the detection sensor S1 through at least one sound hole 40, the sound path 50, and the opening 211. Therefore, the possibility that dust or the like enters the detection sensor S2 from at least one sound hole 40 and the sound path 50 and adheres to the vibration membrane 100 is reduced. In addition, when the cover C is provided, since at least one sound hole 40 is blocked by the cover C, the possibility that dust or the like enters the detection sensor S2 from at least one sound hole 40 and the sound path 50 and adheres to the vibration membrane 100 is further reduced.

[0081] The detection sensor S2 also has the same technical features and effects as the technical features and effects (3) to (5) of the detection sensor S1.

[0082] In addition, since the detection device D is equipped with the detection sensor S2, the detection device D also has the same technical features and effects as the detection sensor S2. EXAMPLES

[0083] Hereinafter, a detection sensor S3 (not shown) according to a third embodiment of the present invention and a number of other embodiments including a design variation thereof will be described with reference to FIGS. 6A to 6C. FIGS. 6A to 6C show the detection sensor S3 of the third embodiment. The detection sensor S3 has the same configuration as the detection sensor S1 described above, except that the holder H further includes a spacer SP interposed between the front side portion 20 and the top plate 210 of the case 200, and at least one sound hole 40 and sound path 50 of the holder H have a different configuration from at least one sound hole 40 and sound path 50 of the holder H of the detection sensor S1. Hereinafter, only the differences will be described in detail, and overlapping descriptions will be omitted. In addition, in FIG. 6A, the Z-Z' direction and the Y-Y' direction are shown in the same way as in FIG. 2A. In FIG. 6B, the Z-Z' direction and the X-X' direction are shown in the same way as in FIG. 2B. In FIG. 6C, the Y-Y' direction and the X-X' direction are shown in the same way as in FIG. 2D.

[0084] The spacer SP is separate from the holding part 10 and the front part 20 of the holder H, has a substantially ring-shaped cross section along the Y-Y' direction and the X-X' direction, and is made of an insulating material (e.g., insulating resin, etc.). The spacer SP has a central hole 52 penetrating the spacer SP in the Z-Z' direction and positioned between the transmitting part 30 and the opening 211 of the case 200 of the unit U. The spacer SP is disposed in the cylindrical part 11 of the holding part 10 having any of the above configurations (1) to (3), and is interposed between the front part 20 of the holder H and the top plate 210 of the case 200 of the unit U. The spacer SP abuts against the front part 20 of the holder H from the Z' direction side and abuts against the top plate 210 of the case 200 from the Z direction. That is, the front part 20 of the holder H abuts indirectly via the spacer SP. There is no gap G between the front portion 20 of the holder H and the top plate 210 of the case 200, and the detection sensor S3 is not provided with at least one stopper 60. In Figs. 6A to 6C, the holding portion 10 of the holder H has the above-mentioned configuration (2).

[0085] The sound path 50 of the holder H of the detection sensor S2 may be provided (a) in the spacer SP, or (b) in both the front portion 20 and the spacer SP.

[0086] When the sound path 50 has the above-mentioned configuration (a), the detection sensor S3 further has any one of the following configurations.

[0087] When the transmitting section 30 has the above configuration (6), the central hole 52 of the spacer SP extends from the second hole 21b of the retaining hole 21 of the front side portion 20 to the opening 211 of the top plate 210 of the case 200 and communicates with the second hole 21b and the opening 211. In this case, the transmitting section 30 is disposed on the Z direction side with respect to the second hole 21b, the central hole 52 of the spacer SP, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. When the transmitting section 30 has the above configuration (7), the central hole 52 of the spacer SP extends from the retaining hole 21 of the front side portion 20 to the opening 211 of the top plate 210 of the case 200 and communicates with the retaining hole 21 and the opening 211. In this case, the transmitting portion 30 is disposed on the Z direction side with respect to the central hole 52 of the spacer SP, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. When the transmitting portion 30 has the configuration (8) above, the central hole 52 of the spacer SP extends from the transmitting portion 30 to the opening 211 of the top plate 210 of the case 200, and communicates with the opening 211. In this case, the transmitting portion 30 is disposed on the Z direction side with respect to the central hole 52 of the spacer SP, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100.

[0088] The one or more sound holes 40 of the holder H of the detection sensor S3 have substantially the same configuration as the one or more sound holes 40 of the holder H of the detection sensor S1, and are provided in the portion around the transmission portion 30 of the front portion 20.

[0089] The sound path 50 of the holder H of the detection sensor S3 extends from one or more sound holes 40 to the opening 211 of the case 200 and communicates with the one or more sound holes 40 and the opening 211. For example, the sound path 50 can be configured to have one or more peripheral holes 53 and a central hole 52 (see Figs. 6A to 6C), or to have one or more side holes (not shown) and a central hole 52. The one or more peripheral holes 53 penetrate the part around the central hole 52 of the spacer SP in the Z-Z' direction and extend from the one or more sound holes 40 to the central hole 52. The one or more side holes are provided in the part around the central hole 52 of the spacer SP and extend from the one or more sound holes 40 to the central hole 52. Sound waves input from the one or more sound holes 40 pass through the sound path 50 and the opening 211 of the case 200 of the unit U to vibrate the diaphragm 100.

[0090] When the sound path 50 has one or more peripheral holes 53 and the holding part 10 has the above configuration (1), the one or more sound holes 40 face the tube part 11 of the holding part 10 and / or the top plate 210 of the case 200 of the unit U through one or more peripheral holes 53, but do not face the opening 211 and the diaphragm 100 of the case 200 of the unit U. When the sound path 50 has one or more peripheral holes 53 and the holding part 10 has the above configuration (2) or (3), the one or more sound holes 40 face the top plate 210 of the case 200 of the unit U through one or more peripheral holes 53, but do not face the opening 211 and the diaphragm 100 of the case 200 of the unit U. In either case, the diaphragm 100 is not exposed to the outside of the holder H through the opening 211 of the case 200, the sound path 50, and the one or more sound holes 40.

[0091] When the sound path 50 has one or more horizontal holes, the one or more sound holes 40 face the bottom of the one or more horizontal holes of the spacer SP, and therefore do not face the opening 211 of the case 200 of the unit U and the vibration membrane 100.

[0092] When the sound path 50 has the above-mentioned configuration (b), the detection sensor S3 further has any one of the following configurations.

[0093] When the holding hole 21 is provided in the front side portion 20 and has the configuration of (4) above, (12) the second hole 21b of the holding hole 21 in the front side portion 20 extends from the first hole 21a to the central hole 52 of the spacer SP, and the central hole 52 of the spacer SP extends from the second hole 21b to the opening 211 of the case 200 of the unit U. In this case, the transmission portion 30 is exposed in the Z direction from the first hole 21a of the holding hole 21 in the front side portion 20. The transmission portion 30 is exposed in the Z' direction from the second hole 21b of the holding hole 21 in the front side portion 20, and is disposed on the Z direction side with respect to the second hole 21b, the central hole 52, the opening 211 of the case 200 of the unit U, and the vibration membrane 100, and faces the vibration membrane 100. Therefore, infrared rays are transmitted through the transmission portion 30 from the Z direction side and irradiated to the vibration membrane 100.

[0094] When the holding hole 21 is provided in the front side portion 20 and the holding hole 21 has the above-mentioned configuration (5), (13) a hole portion (not shown) is provided in the Z'-direction side of the holding hole 21 in the front side portion 20, extending from the holding hole 21 to the central hole 52 of the spacer SP, and the central hole 52 of the spacer SP extends from the hole portion to the opening 211 of the case 200 of the unit U. In this case, the transmission portion 30 is exposed in the Z-direction from the holding hole 21 in the front side portion 20 and is exposed in the Z'-direction from the hole portion of the front side portion 20, and is disposed on the Z-direction side with respect to the hole portion, the central hole 52, the opening 211 of the case 200 of the unit U, and the vibration membrane 100, and faces the vibration membrane 100. Therefore, infrared rays are transmitted through the transmission portion 30 from the Z-direction side and irradiated to the vibration membrane 100.

[0095] In the case where the retaining hole 21 is not provided in the front side portion 20, (14) a hole portion (not shown) is provided in the front side portion 20 extending from the transmitting portion 30 to the central hole 52 of the SP, and the central hole 52 of the spacer SP extends from the hole portion to the opening 211 of the case 200 of the unit U. In this case, the transmitting portion 30 is exposed in the Z direction from the front side portion 20 and exposed in the Z' direction from the hole portion of the front side portion 20, and is disposed on the Z direction side with respect to the hole portion, the central hole 52, the opening 211 of the case 200 of the unit U, and the diaphragm 100, and faces the diaphragm 100. Therefore, infrared rays are transmitted through the transmitting portion 30 from the Z direction side and irradiated to the diaphragm 100.

[0096] The one or more sound holes 40 of the holder H of the detection sensor S3 have substantially the same configuration as the one or more sound holes 40 of the holder H of the detection sensor S2, and are provided in the portion around the transmission portion 30 of the front portion 20.

[0097] The sound path 50 of the holder H of the detection sensor S3 extends from one or more sound holes 40 to the opening 211 of the case 200 and communicates with one or more sound holes 40 and the opening 211. For example, the sound path 50 can be configured to have one or more recesses 51 of the front side portion 20, the second hole 21b of the front side portion 20 (12), the hole portion of the front side portion 20 (13), or the hole portion of the front side portion 20 (14), and the central hole 52 of the spacer SP, or to have one or more horizontal holes (not shown) of the front side portion 20, the second hole 21b of the front side portion 20 (12), the hole portion of the front side portion 20 (13), or the hole portion of the front side portion 20 (14), and the central hole 52 of the spacer SP. One or more recesses 51 are provided in the front portion 20 and extend from one or more sound holes 40 to the second hole 21b of (12), the hole portion of (13), or the hole portion of (14), and extend from one or more sound holes 40 in the Z' direction and open in the Z' direction. One or more lateral holes are provided in the front portion 20 and extend from one or more sound holes 40 to the second hole 21b of (12), the hole portion of (13), or the hole portion of (14). As described above, the central hole 52 of the spacer SP extends from the second hole 21b of (12), the hole portion of (13), or the hole portion of (14) to the opening 211 of the case 200 of the unit U. Sound waves input from one or more sound holes 40 pass through a sound path 50 in the front side portion 20 and an opening 211 in the case 200 of the unit U, causing the diaphragm 100 to vibrate.

[0098] When the sound path 50 has one or more recesses 51 in the front side portion 20, the one or more sound holes 40 face the spacer SP via the one or more recesses 51 in the front side portion 20, but do not face the opening 211 of the case 200 of the unit U and the diaphragm 100. When the sound path 50 has one or more side holes in the front side portion 20, the one or more sound holes 40 face the bottom of the one or more side holes in the front side portion 20, and therefore do not face the opening 211 of the case 200 of the unit U and the diaphragm 100. In either case, the diaphragm 100 is not exposed to the outside of the holder H through the opening 211 of the case 200, the sound path 50, and the one or more sound holes 40.

[0099] The detection device D of the third embodiment has the same configuration as the detection device D of the first embodiment, except that the detection device D includes a detection sensor S3 of any of the above aspects instead of the detection sensor S1 of any of the above aspects.

[0100] The above-described detection sensor S3 provides the following technical features and advantages (1) and (2).

[0101] Technical Features and Effects (1) The detection sensor S3 can receive infrared rays and sound waves from the same direction. The reason is as follows. The front part 20 of the holder H is disposed on the Z direction side with respect to the case 200 of the unit U. The transparent part 30 of the holder H is provided on the front part 20, is exposed from the front part 20 in the Z direction and the Z' direction, and faces the vibration membrane 100 through the central hole 52 of the spacer SP and the opening 211 of the case 200. Therefore, at least infrared rays pass through the transparent part 30 of the holder H from the Z direction side and are irradiated to the vibration membrane 100. In addition, at least one sound hole 40 is provided in a portion around the transparent part 30 of the front part 20 of the holder H and opens in the Z direction. The sound path 50 is provided in the spacer SP, or the front part 20 and the spacer SP, and extends from at least one sound hole 40 to the opening 211 of the case 200. Therefore, sound waves can also be input to at least one sound hole 40 from the Z direction side, pass through at least one sound hole 40, the sound path 50, and the opening 211, and vibrate the diaphragm 100.

[0102] Technical Features and Effects (2) The vibration membrane 100 is not exposed to the outside of the detection sensor S3. The transparent portion 30 of the holder H is provided on the front side portion 20 and faces the vibration membrane 100 through the opening 211 of the case 200. At least one sound hole 40 is provided in a portion around the transparent portion 30 of the front side portion 20 of the holder H. Therefore, the vibration membrane 100 is not exposed to the outside of the detection sensor S1 through at least one sound hole 40, the sound path 50, and the opening 211. Therefore, the possibility that dust or the like enters the detection sensor S3 from at least one sound hole 40 and the sound path 50 and adheres to the vibration membrane 100 is reduced. In addition, when the cover C is provided, since at least one sound hole 40 is blocked by the cover C, the possibility that dust or the like enters the detection sensor S3 from at least one sound hole 40 and the sound path 50 and adheres to the vibration membrane 100 is further reduced.

[0103] The detection sensor S3 also has the same technical features and effects as the technical features and effects (3) to (5) of the detection sensor S1.

[0104] In addition, since the detection device D is equipped with the detection sensor S3, the detection device D also has the same technical features and effects as the detection sensor S3.

[0105] The above-mentioned detection sensor and its connection structure (combination) are not limited to the above-mentioned embodiment, and may be arbitrarily modified in design within the scope of the claims.

[0106] The holding portion 10 of the holder H described above can be arbitrarily modified in design as long as it is configured to hold the unit U of any of the above-mentioned aspects on the Z' direction side relative to the front portion 20 of any of the above-mentioned aspects. The at least one sound hole 40 of the holder H described above can be arbitrarily modified in design as long as it is provided in a portion around the transmission portion 30 of the front portion 20 and opens in the Z direction. The sound path 50 of the holder H described above can be arbitrarily modified in design as long as it extends from the at least one sound hole 40 to the opening 211 of the case 200 of the unit U. [Explanation of symbols]

[0107] D: Detection device S1, S2: Detection sensors U: Sensor unit 100: Vibration membrane 110: Film body 120: First electrode 130: Second electrode 200: Case 210: Top plate 211: Opening 220: Cylinder portion 221: Locking portion 300: Substrate 310: Electrode 400: Field effect transistor 500: Conductive ring 600: Gate Ring 700: Holder H: Holder 10: Holding part 11: Cylindrical part 11a: Thin wall part 11b: Thick wall part 20: Front portion 21: Retaining hole 21a: First hole 21b: Second hole 30: Transparent part 31: Transparent part main body 32: Outer periphery 40: Sound hole 50: Sound path G: Gap 60: Stopper C: Cover SP: Spacer F1: Low-pass filter F2: High pass filter CE: Control unit

Claims

1. A sensor unit; A holder is provided, The sensor unit includes a vibration membrane made of a piezoelectric film, the vibration membrane having a configuration in which a first electric signal is generated by a pyroelectric effect when irradiated with infrared rays, and a second electric signal is generated by a piezoelectric effect when vibrated by sound waves; and a case that houses the vibration membrane, the case has an opening disposed on one side in a first direction with respect to the vibration membrane, the first direction is a thickness direction of the vibration membrane, The holder includes a holding portion that holds the sensor unit; a front portion disposed on one side of the case in the first direction; a transmitting portion through which at least infrared light can pass; A sound hole through which sound waves can be input; It is equipped with a sound path, the transmission portion is provided in the front portion, exposed from the front portion to one side and the other side in the first direction, disposed on one side of the opening and the vibration membrane in the first direction, and facing the vibration membrane; the sound hole is provided in a portion around the transmission portion of the front side portion and opens to one side in the first direction, The sound path extends from the sound hole to the opening of the case.

2. 2. The detection sensor according to claim 1, the front portion is disposed opposite to the case with a gap therebetween on one side in the first direction, the sound path has the gap, the gap communicates with the opening of the case, The sound hole penetrates the portion of the front side around the transparent portion, communicates with the gap, and faces the holding portion and / or the peripheral portion of the opening of the case.

3. The detection sensor according to claim 2, The holder further comprises at least one stopper, The at least one stopper is provided on the front portion or the retaining portion, and is a detection sensor that is arranged on the other side of the first direction relative to the front portion and abuts against the case from one side in the first direction.

4. The detection sensor according to claim 2, The case further includes at least one stopper. The at least one stopper is a detection sensor that extends from the case in one direction in the first direction and abuts against the front side portion from the other side in the first direction.

5. 2. The detection sensor according to claim 1, the front portion is in direct contact with the case of the sensor unit from one side in the first direction, The sound path is a detection sensor provided in the front side portion.

6. 2. The detection sensor according to claim 1, the holder further includes a spacer interposed between the front portion and the case of the sensor unit, the spacer is provided with a central hole penetrating the spacer in the first direction and positioned between the transmission portion and the opening of the case of the sensor unit; The sound path is provided in the spacer, or in the front portion and the spacer, and the detection sensor has the central hole.

7. The detection sensor according to any one of claims 1 to 6, The holding portion is a detection sensor extending from the front portion to the other side in the first direction.

8. The detection sensor according to any one of claims 1 to 6, The transmission section is a detection sensor having an optical filter that transmits infrared light in a predetermined wavelength band.

9. The detection sensor according to any one of claims 1 to 6, The vibration membrane has a film body having a first surface on one side in the first direction and a second surface on the other side in the first direction; a first electrode on the first surface of the film body; a second electrode on the second surface of the film body.

10. The detection sensor according to any one of claims 1 to 6, Further comprising a cover through which sound waves can pass, The cover is provided on a portion of the front portion around the transparent portion and closes the sound hole from one side in the first direction.

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