JP3914185B2 - Temperature sensor using electro-optic effect - Google Patents

Description

  The present invention relates to a temperature sensor using an electro-optical effect that detects a temperature change of an object using a phase difference of detection light corresponding to the electro-optical effect.

  The primary electro-optic (EO) effect is also called the Pockels effect. For example, in a crystal having no inversion symmetry such as an electro-optic crystal (hereinafter also referred to as an EO crystal), the normal light and the extraordinary light 2 Represents the property that the refractive index of seed light waves changes in proportion to the applied electric field (voltage) applied to the crystal, and methods for detecting physical quantities of objects using this electro-optic effect have been studied. (For example, refer nonpatent literature 1).

  In addition, research and development of a transceiver capable of communicating information via a living body using the electro-optic effect of an EO crystal as an information communication means between a wearable computer and another computer (another wearable computer or the like) has been promoted. (For example, refer to Patent Document 1).

Tadashi Shiogama “Development and Application of Ferroelectric Materials”, CMC Publishing JP 2001-352298 A (page 5-10, FIGS. 1 to 4).

  The conventional physical quantity detection method of an object using the electro-optic effect based on the EO crystal is an electro-optic crystal corresponding to a change in an applied electric field according to contact of an object to be detected with an electrode attached to the electro-optic crystal. In this method, a change in refractive index is detected as a phase difference of detection light.

  That is, the conventional physical quantity detection method of an object using the electro-optical effect is to detect a change in intensity of detection light according to the presence or absence of contact of the object with the electrode, in a binary (digital) manner. It has been difficult to detect continuous (analog) changes in objects, particularly temperature changes.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a temperature sensor using an electro-optic effect that can easily detect a temperature change of an object using the electro-optic effect. .

  Further, the present invention has been made in view of the above-described circumstances, and detects a temperature change of an object using the electro-optic effect, and based on the detection result, the moving direction of the object that moves continuously and / or It is another object of the present invention to provide a temperature sensor using an electro-optic effect that can detect the amount of movement.

In order to achieve the above-described object, the present invention provides a temperature using an electro-optical effect that detects a temperature change of an object using a phase difference of detection light corresponding to the electro-optical effect. A first electrode part, an insulating covering member that covers one end surface of the first electrode part, and the first electrode on an optical path of the detection light; An electro-optic crystal member that is disposed adjacent to the portion and has the electro-optic effect and the pyroelectric effect, and a temperature change of the electro-optic crystal member corresponding to the pyroelectric effect and an electric field inside the electro-optic crystal member. A temperature electric field relationship information storage unit for storing information representing a relationship with related parameters; and a second electric field crystal information member attached to the electro-optic crystal member so as to face the first electrode unit with an optical path of the detection light interposed therebetween. An electrode part . The first electrode portion is spaced from the first electrode in contact with the electro-optic crystal member toward the object side from the first electrode, and is disposed opposite to the first electrode. A second electrode; and an elastically deformable connection electrode having temperature conductivity and electrically connecting the first electrode to the second electrode.

According to a second aspect of the present invention, in the temperature sensor according to the first aspect, the electric field for generating the electro-optic effect is transmitted between the second electrode portion and the first electrode portion via the second electrode portion. Application means for applying an electric potential difference to the electro-optic crystal member is further provided.

The invention according to claim 3 is a temperature sensor using an electro-optic effect that detects a temperature change of an object using a phase difference of detection light according to the electro-optic effect, the first electrode unit, An insulating covering member that can contact an object and covers one end surface of the first electrode portion; and is disposed adjacent to the first electrode portion on an optical path of the detection light; and Electro-optic crystal members each having a pyroelectric effect, and a temperature electric field for storing information representing a relationship between a temperature change of the electro-optic crystal member corresponding to the pyroelectric effect and a parameter relating to an electric field inside the electro-optic crystal member A relation information storage unit; and a second electrode unit attached to the electro-optic crystal member so as to face the first electrode unit across an optical path of the detection light. The object is an electric field transmission medium, and when the electric field for generating the electro-optic effect is induced in the electric field transmission medium in a state where the first electrode portion is in contact with the electric field transmission medium, The induced electric field is configured to be applied to the first electrode portion via the electric field transmission medium.

  According to a fourth aspect of the present invention, in the temperature sensor according to any one of the first to third aspects, the parameter is a magnitude of polarization generated in the electro-optic crystal member.

According to a fifth aspect of the present invention, in the temperature sensor according to any one of the first to fourth aspects, the object comes into contact with the insulating coating member and the insulating coating member and the first electrode portion The change in temperature of the object is transmitted to the electro-optic crystal member via the pyroelectric effect of the electro-optic crystal member, and the magnitude of the spontaneous polarization changes according to the temperature change of the object due to the pyroelectric effect of the electro-optic crystal member. When the potential difference between the first electrode portion and the second electrode portion changes according to the change and the phase difference of the detection light changes, the phase difference of the detection light is detected, and the detected phase difference is detected. Detection means for detecting the temperature change is further provided.

In order to achieve the above-described object, the present invention provides an electro-optical effect for detecting a temperature change of an object using a phase difference of a plurality of detection lights according to the electro-optical effect as described in claim 6. The object is in contact with a plurality of first electrodes arranged so that one end surfaces thereof are located on the same plane, and one of each of the plurality of first electrodes. An insulating covering member covering each of the end faces, and a plurality of electro-optic crystals disposed on the optical paths of the plurality of detection lights adjacent to the plurality of first electrodes and having the electro-optic effect and the pyroelectric effect, respectively The relationship between the temperature of each of the plurality of electro-optic crystal members corresponding to the pyroelectric effect of each of the plurality of electro-optic crystal members and the parameter relating to the electric field generated in each of the plurality of electro-optic crystal members is represented. And a plurality of second electrodes attached to the plurality of electro-optic crystal members so as to face the plurality of first electrodes across the optical paths of the plurality of detection lights, respectively. Electrode.

  As described above, according to the temperature sensor of the present invention, the electro-optic crystal member having the electro-optic effect and the pyroelectric effect respectively responds to the temperature change of the object using the pyroelectric effect. The change in spontaneous polarization of the electro-optic crystal member can be detected, and the change in spontaneous polarization can be detected as a change in phase difference of detection light due to the electro-optic effect of the electro-optic crystal member.

  Then, from the change in the phase difference of the detection light, the pyroelectric effect determines the change in the parameter relating to the electric field inside the electro-optic crystal member corresponding to the change in the phase difference, and the temperature change corresponding to the parameter change, It can be obtained from information representing the relationship between the temperature of the electro-optic crystal member and the parameter relating to the electric field inside the electro-optic crystal member.

  As a result, it is possible to easily detect a continuous (analog) temperature change generated in the object.

  Embodiments of a temperature sensor using an electro-optic effect according to the present invention will be described with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of a temperature sensor 1 using an electro-optic effect according to the first embodiment of the present invention.

  The temperature sensor 1 of the present embodiment is a sensor that detects a temperature change of, for example, the living body H that is a grounded object.

  As shown in FIG. 1, the temperature sensor 1 has, for example, a substantially thin plate shape, and is attached to, for example, a metal detection electrode 2 having high temperature conductivity and one surface 2 a of the detection electrode 2. An ultra-thin insulating member, such as silicon dioxide or alumina, that covers the surface 2a, for example, a flexible and high-temperature conductive insulating material such as silicon rubber, or that has good adhesion to the electrode material of the detection electrode 2 and high temperature conductivity. And an insulating film 3 made of the same. Further, the surface 3a opposite to the detection electrode side of the insulating film 3 is exposed to the outside so that at least a part of the living body H can be contacted.

  The temperature sensor 1 has, for example, a rectangular parallelepiped shape, and includes an electro-optic crystal (electro-optic crystal member, hereinafter referred to as an EO crystal) 5 having an electro-optic effect (Pockels effect) and a pyroelectric effect. ing. Examples of the EO crystal 5 include a crystal having a perovskite structure (ferroelectric material such as PZT and LiNbO3).

  The EO crystal 5 has a first side surface 5a along the longitudinal direction, and a second side surface 5b opposite to the first side surface 5a. The first side surface 5a and the second side surface The distance (thickness) between 5b is a constant value (hereinafter referred to as d). Further, the longitudinal lengths of the first and second side surfaces 5a and 5b in the EO crystal 5 are longer than the longitudinal length of the detection electrode 2, for example.

  The detection electrode 2 is attached to the first side surface 5 a adjacent to the first side surface 5 a of the EO crystal 5.

  Furthermore, the temperature sensor 1 converts, for example, laser light, which is detection light having a substantially single wavelength, into laser light parallel to the longitudinal direction of the detection electrode 2 as detection light for detecting a change in living body temperature, and the parallel laser light is converted into the detection light. , For example, includes a detection light output unit 10 that outputs laser light L1 in a state of being polarized into circularly polarized light or linearly polarized light rotated by 45 ° with respect to the principal axis of the electro-optic crystal 5. The portion is disposed so as to be positioned on the optical path of the laser beam output from the detection light output unit 10.

  The temperature sensor 1 includes an application electrode 12 that is attached to the second side surface 5b of the EO crystal 5 and is disposed to face the detection electrode 2, and applies an electric field to the EO crystal 5 through the application electrode 12. The electric field application unit 13 is provided. The application electrode 12 has substantially the same shape as the detection electrode 2.

  Further, the temperature sensor 1 detects a change in the phase difference of the laser light L2 that has passed through the EO crystal 5 as a change in the intensity of the laser light by a polarization detection optical system including a wave plate, a polarizer, a polarization beam splitter, and the like. A detection unit 15 is provided for converting the detected intensity change of the laser light into an electric signal via a photoelectric converter such as a photodetector. In the first embodiment, the EO crystal 5, the detection light output unit 10, and the detection unit 15 constitute an electric field detection optical unit 20.

  2 shows a schematic configuration of an electric field detection unit 32 and an information processing circuit 42 that are electrically connected to the electric field detection optical unit 20 in the temperature sensor 1 shown in FIG. FIG.

  That is, the electric field detection unit 32 includes a signal processing circuit 38. The signal processing circuit 38 forms a receiving unit 36 together with the electric field detection optical unit 20, is connected to the detection unit 15 of the electric field detection optical unit 20, and amplifies the electric signal output from the detection unit 15. Signal processing such as processing and noise removal processing is performed.

  The electric field detection unit 32 is connected to the signal processing circuit 38, and a waveform shaping circuit 40 that performs waveform shaping processing on the electric signal signal-processed by the signal processing circuit 38, and the electric signal as reception data, An I / O circuit 44 that transmits to an information processing circuit (for example, a circuit incorporating a computer) 42 for physical quantity detection processing is provided.

  The information processing circuit 42 in the temperature sensor 1 includes a parameter P relating to the temperature T of the EO crystal 5 corresponding to the pyroelectric effect of the EO crystal 5 and the electric field inside the EO crystal 5, for example, the magnitude P of polarization generated in the EO crystal 5. The relationship data RD in which information representing the relationship is converted into data is stored.

  FIG. 3 is a graph conceptually showing the relationship data RD, and the value of the polarization magnitude P of the EO crystal 5 corresponding to the value of the temperature T of the EO crystal 5 is associated with each other based on a predetermined resolution. For example, it is stored in advance as a table format.

  On the other hand, the electric field application unit 13 generates an electric field based on a signal input via the I / O circuit 46 for connecting an external device and, for example, the I / O circuit 46, and generates a potential difference V between the application electrode 12 and the detection electrode 2. And an electric field application circuit 48 for applying to the EO crystal 5 through the application electrode 12.

  Next, the overall operation of the temperature sensor 1 of the present embodiment will be described.

In general, when an external electric field E is applied to a dielectric according to Maxwell's equation, the electric displacement (electric flux density) D in the dielectric is determined by ε _{0 as} the dielectric constant in vacuum and by the external electric field E. When the polarization (electric polarization) generated in the body is P, it can be expressed by the following formula (1).

D = ε ₀ E + P (1)
At this time, for example, the polarization P generated in the crystal as the dielectric can be expressed as the following equation (2): P = εE (2)
Where ε is the dielectric constant of the crystal, and E is the electric field applied to the EO crystal 5 from the outside.

  Here, ε is expressed as a tensor, and the polarization P is expressed as the following equation (3).

一方、本実施形態において、ＥＯ結晶５には、検出光出力部１０から出力されたレーザ光Ｌ１が入射されている。ＥＯ結晶５は、そのＥＯ結晶５に対して検出電極２および印加電極１２間に印加されている電位差Ｖに対応する外部電界Ｅ（Ｅ＝Ｖ／ｄ）が変化すると、その電気光学効果により、ＥＯ結晶５の分極Ｐおよび屈折率ｎがそれぞれ変化する。この結果、ＥＯ結晶５内を通過するレーザ光Ｌ１に対して、下式（４）で表される位相差Ψが発生する。

On the other hand, in this embodiment, the laser beam L1 output from the detection light output unit 10 is incident on the EO crystal 5. When the external electric field E (E = V / d) corresponding to the potential difference V applied between the detection electrode 2 and the application electrode 12 with respect to the EO crystal 5 changes, the EO crystal 5 changes due to its electro-optical effect. The polarization P and the refractive index n of the EO crystal 5 change. As a result, a phase difference Ψ represented by the following expression (4) is generated for the laser light L1 passing through the EO crystal 5.

Ψ = (2π / λ) · n ³ γV (4)
Here, λ is the wavelength of the laser beam L1, and γ is the Pockels coefficient of the EO crystal 5.

  Here, when the grounded living body H comes into contact with the insulating film 3 through, for example, a part (such as a finger), the temperature change ΔT of the living body H is caused as a thermal change through the insulating film 3 and the detection electrode 2. It is transmitted to the EO crystal 5 with almost no loss.

  At this time, since the EO crystal 5 in this embodiment has a pyroelectric effect, that is, an effect that the magnitude of the spontaneous polarization of the crystal 5 changes due to the temperature change of the crystal, the temperature change ΔT of the transmitted living body H The magnitude Ps of the spontaneous polarization of the EO crystal 5 changes due to the temperature change of the EO crystal 5 due to the above, and the electric field Es inside the EO crystal 5 corresponds to the change of the magnitude Ps of the spontaneous polarization according to the above equation (2). Change.

  In accordance with the change in the internal electric field Es, the polarization P and the refractive index n of the entire EO crystal 5 change, the potential difference V shown in the above equation (4) changes, and the phase difference ψ1 of the laser light L1 changes.

  Thus, when passing through the EO crystal 5, the laser beam L 2 whose phase difference Ψ 1 has changed in accordance with the temperature change ΔT of the living body H (temperature change of the EO crystal 5) changes in intensity via the detection unit 15. And is subjected to amplification, waveform shaping processing and the like via the signal processing circuit 38 and the waveform shaping circuit 40, and then transmitted to the information processing circuit 42 via the I / O circuit 44.

  The information processing circuit 42 receives the transmitted data, that is, data representing the laser light intensity change corresponding to the temperature change ΔT of the living body H (change in the phase difference Ψ1 of the laser light L2).

  At this time, the information processing circuit 42 calculates a change in the polarization magnitude P corresponding to the received data based on the received data, and calculates a temperature change ΔT corresponding to the calculated change in the polarization magnitude P. It can be extracted with reference to the relational data RD shown in FIG.

  As described above, according to the temperature sensor 1 according to the present embodiment, the temperature change ΔT of the living body H is measured using the pyroelectric effect by the EO crystal 5 having the electro-optic effect and the pyroelectric effect. The change in the spontaneous polarization Ps corresponding to the change ΔT can be detected, and the change in the spontaneous polarization Ps can be detected as a change in the phase difference Ψ1 of the laser light L1 due to the electro-optic effect.

  The temperature change ΔT of the living body H can be obtained from the correspondence between the change in the polarization P of the EO crystal 5 corresponding to the change in the phase difference ψ1 of the laser light L1 and the change in the temperature T.

  As a result, a temperature change that is a continuous (analog) change occurring in the living body H can be easily detected.

  In the temperature sensor 1 shown in FIGS. 1 and 2, the insulating film 3 is attached to one surface 2a of the detection electrode 2 to cover the one surface 2a. However, the present invention is not limited to this configuration. For example, like the temperature sensor 1A shown in FIG. 4, the insulating film 3 is removed from the configuration of FIG. 1, and one surface 2a of the detection electrode 2 is exposed to the outside, so that the living body H can directly contact the detection electrode 2. You may do it.

(Second Embodiment)
FIG. 5 is a diagram showing a schematic configuration of a temperature sensor 1B according to the second embodiment of the present invention, and FIG. 6 is electrically connected to the electric field detection optical unit 60 in the temperature sensor 1B shown in FIG. 2 is a block diagram showing a schematic configuration of an electric field detection unit 32 and an information processing circuit 42 which are signal processing systems, and a schematic configuration of an electric field application unit 13, respectively.

  The temperature sensor 1B of the present embodiment includes a first electrode (detection electrode) 61 having a substantially thin plate shape, for example, attached to the first side surface 5a adjacent to the first side surface 5a of the EO crystal 5. The first electrode 61 is made of, for example, metal having high temperature conductivity.

  Further, the temperature sensor 1B includes a second electrode 62 having substantially the same shape as the first electrode 61 disposed to face the first electrode 61 at a predetermined interval. The electrode 62 is made of, for example, metal having high temperature conductivity.

  Further, the temperature sensor 1B includes an elastically deformable connection electrode 63 that electrically connects the first electrode 61 to the second electrode 62, and the insulating film 3 is formed on the second electrode 62. The surface 62a opposite to the first electrode 61 side is covered.

  The connection electrode 63 is made of a material having conductivity, high temperature conductivity, and elastic deformation. Further, for example, a metal foil (aluminum foil or the like) may be formed in a bellows shape.

  In addition, about the other structure of the temperature sensor 1B concerning 2nd Embodiment, since it is substantially equivalent to the component of the temperature sensor 1 concerning 1st Embodiment, the same code | symbol is attached | subjected and the description is given. Is omitted or simplified.

  Next, the overall operation of the temperature sensor 1B of the present embodiment will be described.

  Similar to the first embodiment, when the grounded living body H contacts the insulating film 3 through, for example, a part thereof, the insulating film 3, the second electrode 62, the connection electrode 63, and the first electrode 61 are Since each has high temperature transferability, the temperature change ΔT of the living body H is transmitted as heat change to the EO crystal 5 through the insulating film 3, the second electrode 62, the connection electrode 63 and the first electrode 61 with almost no loss. The temperature change ΔT is generated in the EO crystal 5 by the transmitted temperature change ΔT.

  At this time, in the present embodiment, the second electrode 62 on the side in contact with the living body H is separated from the EO crystal 5 and is elastic with a material having high temperature conductivity with respect to the first electrode 61 on the EO crystal 5 side. The connection electrodes 63 are formed so as to be deformable.

  Therefore, the pressure generated in the second electrode 62 due to the contact of the living body H with the insulating film 3 can be absorbed by the elastic deformation of the connection electrode 63, and the contact pressure of the living body H acts on the EO crystal 5. Can be suppressed.

  As a result, the contact pressure of the living body H with respect to the change in the phase difference Ψ1 of the laser light L1 based on the change in the spontaneous polarization magnitude Ps of the EO crystal 5 due to the temperature change ΔT of the living body H transmitted to the EO crystal 5. It is possible to suppress the inclusion of the phase change component due to.

  Therefore, the noise component resulting from the contact pressure of the living body H included in the electrical signal representing the intensity change of the laser light detected via the detection unit 15 can be reduced, and the temperature change accompanying the contact operation of the living body H High detection accuracy can be maintained.

  In the temperature sensor 1B shown in FIGS. 5 and 6, the insulating film 3 is attached to one surface 62a of the second electrode 62 to cover the one surface 62a. However, the present invention is limited to this configuration. Instead, for example, like the temperature sensor 1C shown in FIG. 7, the insulating film 3 is removed from the configuration of FIGS. 5 and 6, and the one surface 62a of the second electrode 62a is exposed to the outside, so that the living body H is You may make it contact the 2nd electrode 62 directly.

(Third embodiment)
FIG. 8 is a diagram showing a schematic configuration of a temperature sensor 1D according to the third embodiment of the present invention. FIG. 9 is electrically connected to the electric field detection optical unit 70 in the temperature sensor 1D shown in FIG. Disclosed in the above-mentioned Patent Document 1 for applying an electric field to the detection electrode 2 through the living body H as an electric field transmission medium It is a block diagram which shows schematic structure of a transceiver, respectively.

  As shown in FIG. 8, the electric field detection optical unit 70 in the temperature sensor 1 </ b> D of the present embodiment is attached to the second side surface 5 b of the EO crystal 5 instead of the application electrode, and is disposed to face the detection electrode 2. A ground electrode 71 is provided, and the ground electrode 71 is grounded.

  On the other hand, for example, a transceiver 75 as a part of a wearable computer is attached to the living body H in the temperature sensor 1D of the present embodiment.

  The transceiver 75 includes an application electrode 76 disposed so as to be in contact with the living body H directly or via an insulating member such as an insulating film, an information processing circuit 78 having an information generation function for generating an electric field, and the like. An I / O circuit 80 having an interface function related to input / output of information to / from the circuit 78, and a constant electric field based on electric field generation information input through the I / O circuit 80 are applied to the living body H through the application electrode 76. And an electric field applying unit 82 including an electric field applying circuit 82a for inducing the electric field.

  In addition, about the other structure of temperature sensor 1D concerning 3rd Embodiment, since it is substantially equivalent to the component of temperature sensor 1 concerning 1st Embodiment, the same code | symbol is attached | subjected and the description is given. Is omitted or simplified.

  Next, the overall operation of the temperature sensor 1D of the present embodiment will be described.

  In the present embodiment, an electric field is induced through the information processing circuit 78 and the electric field application unit 82 of the transceiver 75 on the application electrode 76 that is in contact with the living body H directly or through an insulating film or the like.

  At this time, when the living body H comes into contact with the insulating film 3 through, for example, a part thereof, the electric field induced in the living body H is applied to the detection electrode 2 through the insulating film 3.

  Since the ground electrode 71 disposed opposite to the detection electrode 2 across the EO crystal 5 is grounded, a potential difference V corresponding to the applied electric field is applied to the EO crystal 5 between the detection electrode 2 and the ground electrode 71. The

  At this time, also in the present embodiment, the laser beam L1 output from the detection light output unit 10 is incident on the EO crystal 5.

  Here, it is assumed that a temperature change ΔT occurs in the living body H that is in contact with the insulating film 3.

  This temperature change ΔT of the living body H is transmitted to the EO crystal 5 as a heat change through the insulating film 3 and the detection electrode 2, and due to the temperature change of the EO crystal 5 due to the transmitted temperature change ΔT of the living body H, the EO crystal 5 The spontaneous polarization magnitude Ps of the EO crystal 5 changes according to the change of the spontaneous polarization magnitude Ps according to the above equation (2).

  In accordance with the change in the internal electric field Es, the polarization P and the refractive index n of the entire EO crystal 5 change, the potential difference V shown in the above equation (4) changes, and the phase difference ψ1 of the laser light L1 changes.

  Thus, when passing through the EO crystal 5, the laser beam L 2 whose phase difference Ψ 1 has changed in accordance with the temperature change ΔT of the living body H (temperature change of the EO crystal 5) changes in intensity via the detection unit 15. And is subjected to amplification, waveform shaping processing and the like via the signal processing circuit 38 and the waveform shaping circuit 40, and then transmitted to the information processing circuit 42 via the I / O circuit 44.

  The information processing circuit 42 receives the transmitted data, that is, data representing the laser light intensity change corresponding to the temperature change ΔT of the living body H (change in the phase difference Ψ1 of the laser light L2).

  At this time, the information processing circuit 42 calculates a change in the polarization magnitude P corresponding to the received data based on the received data, and calculates from the calculated change in the polarization magnitude P and the relationship data RD. A temperature change ΔT corresponding to the change in the polarization magnitude P can be calculated.

  As described above, according to the present embodiment, when the transceiver 75 is attached to the living body H, the electric field induced from the transceiver 75 on the living body H is applied to the detection electrode 2 of the temperature sensor 1D. The potential difference V between the detection electrode 2 and the ground electrode 71 is applied to the EO crystal 5.

  For this reason, in the temperature sensor 1D, the potential is applied to the EO crystal 5 by simply providing the ground electrode 71 without providing the electric field applying unit in the temperature sensors 1 and 1A to 1C according to the first and second embodiments. It becomes possible to apply.

  As a result, in addition to the effects of the first embodiment, the temperature sensor 1D can be downsized. Even if a living body that does not have the transceiver 75 contacts the insulating film 3 of the temperature sensor 1D, only the contact is detected by the temperature sensor 1D. For this reason, the detection target of temperature sensor 1D can be limited, and the security in temperature change detection using temperature sensor 1D can be improved.

(Fourth embodiment)
FIG. 10 is a diagram showing a schematic configuration of a temperature sensor 1E according to the fourth embodiment of the present invention. FIG. 11 is electrically connected to the electric field detection optical unit 70a in the temperature sensor 1E shown in FIG. The schematic configuration of the electric field detection unit 32 and the information processing circuit 42 which are the signal processing system, and the schematic configuration of the transceiver disclosed in Patent Document 1 for applying an electric field to the detection electrode 2 via the living body H It is a block diagram shown respectively.

  As in the second embodiment, the temperature sensor 1E according to the present embodiment includes a first electrode 61 attached to the first side surface 5a of the EO crystal 5 and the first electrode 61, as shown in FIGS. A second electrode 62 disposed opposite to the first electrode 61 at a predetermined interval, and an elastically deformable connection electrode for electrically connecting the first electrode 61 to the second electrode 62 63, and the insulating film 3 covers the surface 62a of the second electrode 62 opposite to the first electrode 61 side.

  And the electric field detection optical part 70a in the temperature sensor 1E of this embodiment is attached with respect to the 2nd side surface 5b of the EO crystal 5 as shown in FIG. 10 and FIG. 11 similarly to 3rd Embodiment. The transceiver 75 having the same configuration as that of the third embodiment is attached to the living body H in the temperature sensor 1E of the present embodiment.

  The other components of the temperature sensor 1E according to the fourth embodiment are substantially the same as those of the temperature sensor 1B according to the second embodiment and the temperature sensor 1D according to the third embodiment. For this reason, the same reference numerals are used and the description thereof is omitted or simplified.

  Next, the overall operation of the temperature sensor 1E of this embodiment will be described.

  As in the third embodiment, an electric field is induced on the application electrode 76 that is brought into contact with the living body H directly or through an insulating film or the like via the information processing circuit 78 and the electric field application unit 82 of the transceiver 75. .

  At this time, when the living body H comes into contact with the insulating film 3 through, for example, a part thereof, the electric field induced in the living body H is applied to the second electrode 62 through the insulating film 3, and the connection electrode 63 is connected. And applied to the first electrode 61.

  At this time, since the ground electrode 71 disposed opposite to the first electrode 61 with the EO crystal 5 interposed therebetween is grounded, an applied electric field is applied to the EO crystal 5 between the first electrode 61 and the ground electrode 71. A potential difference V corresponding to is applied.

  At this time, also in the present embodiment, the laser beam L1 output from the detection light output unit 10 is incident on the EO crystal 5.

  Here, it is assumed that a temperature change ΔT occurs in the living body H that is in contact with the insulating film 3.

  The temperature change ΔT of the living body H is applied to the EO crystal 5 through the insulating film 3, the second electrode 62, the connection electrode 63, and the first electrode 61 as a thermal change with substantially no loss as in the second embodiment. The transmitted temperature change ΔT causes a temperature change ΔT in the EO crystal 5.

  Due to the temperature change of the EO crystal 5, the magnitude Ps of spontaneous polarization of the EO crystal 5 changes, and the electric field Es inside the EO crystal 5 corresponds to the change of the magnitude Ps of spontaneous polarization according to the above equation (2). Change.

  In accordance with the change in the internal electric field Es, the polarization P and the refractive index n of the entire EO crystal 5 change, the potential difference V shown in the above equation (4) changes, and the phase difference ψ1 of the laser light L1 changes.

  Thus, when passing through the EO crystal 5, the laser beam L 2 whose phase difference Ψ 1 has changed in accordance with the temperature change ΔT of the living body H (temperature change of the EO crystal 5) changes in intensity via the detection unit 15. And is subjected to amplification, waveform shaping processing and the like via the signal processing circuit 38 and the waveform shaping circuit 40, and then transmitted to the information processing circuit 42 via the I / O circuit 44.

  The information processing circuit 42 receives the transmitted data, that is, data representing the laser light intensity change corresponding to the temperature change ΔT of the living body H (change in the phase difference Ψ1 of the laser light L2).

  At this time, the information processing circuit 42 calculates a change in the polarization magnitude P corresponding to the received data based on the received data, and calculates from the calculated change in the polarization magnitude P and the relationship data RD. A temperature change ΔT corresponding to the change in the polarization magnitude P can be calculated.

  As described above, according to the present embodiment, when the transceiver 75 is attached to the living body H, the electric field induced from the transceiver 75 on the living body H is generated by the insulating film 3 of the temperature sensor 1E, the second The voltage is applied to the first electrode 61 via the electrode 62 and the connection electrode 63, and is applied to the EO crystal 5 as a potential difference V between the first electrode 61 and the ground electrode 71.

  For this reason, in the temperature sensor 1E, the potential is applied to the EO crystal 5 by simply providing the ground electrode 71 without providing the electric field applying part in the temperature sensors 11, 1A to 1C according to the first and second embodiments. It becomes possible to apply.

  As a result, in addition to the effects of the second embodiment, the temperature sensor 1E can be reduced in size and improved in security as in the third embodiment.

  In the third and fourth embodiments described above, even when the transceiver 75 is not attached to the living body H, the living body H is ungrounded and has a predetermined potential difference with respect to the ground electrode 71. When the living body H is in contact with the insulating film 3, an electric field based on the potential difference of the living body H is applied to the detection electrode 2 or the first electrode via the insulating film 3, and the temperature change ΔT is calculated. Can be detected. For this reason, it is also possible to make temperature sensor 1D and 1E function as a contact detection sensor which detects the contact of the biological body H.

(Fifth embodiment)
FIG. 12 is a diagram showing a schematic configuration of a temperature sensor 1F according to the fifth embodiment of the present invention.

As shown in FIG. 12, the temperature sensor 1F has a plurality of detection electrodes 2x ₁ ,..., 2x _n corresponding to the detection electrodes shown in FIGS. ₁ ,..., 2 × _n are arranged so as to be in non-contact with each other, for example, in a column shape or a matrix shape, and so that one surface 2 a thereof is positioned on the same plane.

The temperature sensor 1F includes a dielectric film 3x to cover all its one surface 2a to the respective one surface 2a of the detection electrode 2x ₁ ~2x _n at a substantially uniform thickness (corresponding to the insulating film 3) .

Furthermore, the temperature sensor 1F, the detection electrode _2x 1 _~2x is provided corresponding to each of _n, each of the detection electrodes _2x 1 _{~2x n} field detecting unit for detecting an electric field through the _32x 1 _{~32x n} (corresponding to the electric field detecting unit 32) is provided corresponding to the electric field detecting unit _32x 1 _{~32x n,} an electric field is applied for applying an electric field to each of the electric field detecting unit _32x 1 _{~32x n} Units 13x _{1 to} 13x _n (corresponding to the electric field applying unit 13).

FIG. 13 is a block diagram showing a schematic configuration of the electric field detection units 32x _{1 to} 32x _n and the information processing circuit 42 in the temperature sensor 1F shown in FIG. 12, and a schematic configuration of the electric field application units 13x _{1 to} 13x _n .

As shown in FIG. 13, each of the electric field detection units 32x _{1 to} 32x _n includes an electric field detection optical unit 20, and the electric field detection optical unit 20 is arranged in the longitudinal direction in the same manner as in the first embodiment. and each of the detection electrodes 2x ₁ ~2x _n is attached to the corresponding to the first side surface 5a along a EO crystal 5 having an electro-optic effect and pyroelectric effect, respectively (see FIG. 1), the detecting electrode 2 Detection light output that outputs laser light parallel to the longitudinal direction as laser light L1 in a state of being polarized with respect to the EO crystal 5, for example, circularly polarized light or linearly polarized light rotated by 45 ° with respect to the principal axis of the electro-optic crystal 5 A detection unit 15 (see FIG. 1) and a detection unit 15 that detects a change in the phase difference of the laser beam that has passed through the EO crystal 5 as an intensity change of the laser beam and converts the detected intensity change of the laser beam into an electrical signal. 1) .

Each electric field applying unit _13x 1 _{~13x n} is attached to each EO crystal 5 of the electric field detecting unit _32x 1 _{~32x n,} in the respective detection electrodes _2x 1 _{~2x n} across the optical path of the laser beam L1 The application electrodes 12 arranged to face each other, the I / O circuit 46 for connecting an external device, and, for example, a constant electric field based on a signal input through the I / O circuit 46 is applied to each of the electric field application units 13x _{1 to} 13x. and a field application circuit 48 to be applied to the application electrode 12 via the respective detection electrodes _2x 1 _{~2x n} as a constant potential difference V between the application electrode 12 and the detection electrodes _2x 1 _{~2x n} of _n.

The electric field detectors 32x _{1 to} 32x _n receive the signal processing such as amplification processing and noise removal processing on the electrical signal output from the detection unit 15 as in the first embodiment. Signal processing circuit 38, a waveform shaping circuit 40 for performing waveform shaping processing on the electrical signal processed by the signal processing circuit 38, and an I / O for transmitting the electrical signal to the information processing circuit 42 as received data. Circuit 44.

As in the first embodiment, the information processing circuit 42 in the temperature sensor 1F includes parameters related to the temperature T of each EO crystal 5 and the electric field inside each EO crystal 5 corresponding to the pyroelectric effect of each EO crystal 5. For example, relation data RD in which information representing the relation with the magnitude P of polarization generated in each EO crystal 5 is converted into data is stored. In the present embodiment, the electric field detector 32x ₁ ~32x _n each EO crystal 5 have the same shape formed of the same material with each other, the relationship data RD, all EO crystal 5 In common.

  Next, the overall operation of the temperature sensor 1F of the present embodiment will be described.

Now, for example, at time A, bio H being grounded, the respective detection electrodes 2x ₁ ~2x _n end surface area is small operating portion than 2a (for example, a fingertip or the like) via a so shown in FIG. 14 to come into contact with the portion between the detection electrode _{2x k-1} and the detection electrode _{2x k (1 ≦ k ≦ n} ) in the insulating film 3x, less continuously towards the contact site to the detection electrode 2x _k will move to, at time B, and the portion reaching the portion facing to the detection electrode 2x _k of the insulating film 3x, beyond the portion facing the detection electrode 2x _k at time C, and opposed to the detection electrode 2x k _{+ 1} at time Z Suppose each arrives.

Here, when the operating part of a living body H is directed to the opposite position of the detection electrode 2x _k away from the position facing the detection electrode _{2x k-1,} through the electric field detector _{32x k-1} corresponding to the detection electrode _{2x k-1} Thus, the temperature of the living body H detected by the information processing unit 42 decreases, and the temperature of the living body H detected by the information processing unit 42 increases via the electric field detection unit 32x _k corresponding to the detection electrode 2x _k .

Similarly, when the operation portion of the subject H is directed to the detection electrode 2x k _{+ 1} of the opposing positions away from the position facing the detection electrode 2x _k, the information processing unit 42 through the electric field detector 32x _k corresponding to the detection electrode 2x _k The detected temperature of the living body H decreases, and the temperature of the living body H detected by the information processing unit 42 increases via the electric field detection unit 32x _{k + 1} corresponding to the detection electrode 2x _{k + 1} .

Therefore, the information processing circuit 42, based on the change in the phase difference detected by the electric field detecting unit _32x 1 _{~32x n} detection electrodes _2x 1 _{~2x n} (temperature changes), for example first field temperature change is detected The distance from the detection unit to the electric field detection unit where the last temperature change is detected and the direction thereof can be easily detected as the movement amount and the movement direction of the operation part of the living body H, that is, the contact part with respect to the insulating film 3x. it can.

Also in the present embodiment, for example, as in the third embodiment, the electric field application units 13x _{1 to} 13x _n are replaced with the ground electrodes, and the electric field application units 13x _{1 to} 13x _n are removed. it is also possible to apply an electric field induced in the living body H by the transceiver attached to the respective detection electrodes 2x ₁ ~2x _n.

  In the first to fifth embodiments and the modifications thereof, the living body is an object that causes a temperature change, which is a detection target of the temperature sensor. However, the present invention is not limited to this and is not a living body. An object having a temperature of

  Furthermore, in the first to fifth embodiments, the signal processing circuit is configured outside the electric field detection unit, but may be configured integrally in the electric field detection unit.

  In the first to fifth embodiments, for example, the magnitude P of the polarization generated in the EO crystal 5 is used as the parameter relating to the electric field in the EO crystal 5 representing the relationship of the EO crystal 5 to the temperature T. The present invention is not limited to this configuration, and may be a parameter related to the electric field inside the EO crystal 5, for example, a parameter such as the electric field inside the EO crystal 5.

1 is a diagram showing a schematic configuration of a temperature sensor using an electro-optic effect according to a first embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of an electric field detection unit and an information processing circuit, which are signal processing systems electrically connected to an electric field detection optical unit in the temperature sensor shown in FIG. 1, and a schematic configuration of an electric field application unit. The graph which shows notionally the relationship data showing the relationship between the magnitude | size of the polarization of EO crystal concerning 1st Embodiment, and temperature. The figure which shows schematic structure of the temperature sensor using the electro-optical effect concerning the modification of 1st Embodiment. The figure which shows schematic structure of the temperature sensor using the electro-optic effect concerning the 2nd Embodiment of this invention. FIG. 6 is a block diagram showing a schematic configuration of an electric field detection unit and an information processing circuit, which are signal processing systems electrically connected to an electric field detection optical unit in the temperature sensor shown in FIG. 5, and a schematic configuration of an electric field application unit. The figure which shows schematic structure of the temperature sensor using the electro-optic effect concerning the modification of 2nd Embodiment. The figure which shows schematic structure of the temperature sensor using the electro-optic effect concerning the 3rd Embodiment of this invention. 8 is a schematic configuration of an electric field detection unit and an information processing circuit, which are signal processing systems electrically connected to an electric field detection optical unit in the temperature sensor shown in FIG. 8, and an electric field applied to the detection electrode via a living body which is an electric field transmission medium. FIG. 3 is a block diagram showing a schematic configuration of a transceiver for applying a signal to each other. The figure which shows schematic structure of the temperature sensor using the electro-optic effect concerning the 4th Embodiment of this invention. 10 is a schematic configuration of an electric field detection unit and an information processing circuit, which are signal processing systems electrically connected to an electric field detection optical unit in the temperature sensor shown in FIG. 10, and an electric field for applying an electric field to a detection electrode via a living body. The block diagram which shows the schematic structure of a transceiver, respectively. The figure which shows schematic structure of the temperature sensor concerning the 5th Embodiment of this invention. FIG. 13 is a block diagram showing a schematic configuration of an electric field detection unit and an information processing circuit and a schematic configuration of an electric field application unit in the temperature sensor shown in FIG. 12. The figure showing the relationship between the movement of the biological body concerning 5th Embodiment, and a detection electrode and an electric field detection part.

Explanation of symbols

1,1A～1F ... Temperature sensor 2,2x ₁ ~2x n _... detection electrode 3,3X ... insulating film 5 ... EO crystal 10 ... detection light output portion 12, 76 ... application electrode 13,13x ₁ ~13x _n, 82 ... electric field applying section 15 ... detector 20 ... field detection optical section 32,32x ₁ ~32x n _... field detecting unit 36 ... receiving portion 38 ... signal processing circuit 40 ... waveform shaping circuit 42,78 ... data processing circuit 61 ... first Electrodes 60, 70, 70a ... Electric field detection optical unit 62 ... Second electrode 63 ... Connection electrode 71 ... Ground electrode 75 ... Transceiver 82a ... Electric field application circuit

Claims (6)

A temperature sensor using an electro-optic effect that detects a temperature change of an object using a phase difference of detection light corresponding to the electro-optic effect,
A first electrode part;
An insulating covering member that can contact the object and covers one end surface of the first electrode portion;
An electro-optic crystal member disposed adjacent to the first electrode portion on the optical path of the detection light and having the electro-optic effect and the pyroelectric effect, and
A temperature electric field relationship information storage unit for storing information representing a relationship between a temperature change of the electrooptic crystal member corresponding to the pyroelectric effect and a parameter relating to an electric field inside the electrooptic crystal member;
A second electrode portion attached to the electro-optic crystal member so as to face the first electrode portion across the optical path of the detection light ;
The first electrode portion includes:
A first electrode in contact with the electro-optic crystal member;
A second electrode spaced from the first electrode toward the object side and disposed opposite the first electrode;
A temperature sensor comprising temperature-conductive and elastically deformable connection electrodes that electrically connect the first electrode to the second electrode . And an applying means for applying the electric field for generating the electro-optic effect to the electro-optic crystal member as a potential difference between the second electrode part and the first electrode part via the second electrode part. The temperature sensor according to claim 1 . A temperature sensor using an electro-optic effect that detects a temperature change of an object using a phase difference of detection light corresponding to the electro-optic effect,
A first electrode part;
An insulating covering member that can contact the object and covers one end surface of the first electrode portion;
An electro-optic crystal member disposed adjacent to the first electrode portion on the optical path of the detection light and having the electro-optic effect and the pyroelectric effect, and
A temperature electric field relationship information storage unit for storing information representing a relationship between a temperature change of the electrooptic crystal member corresponding to the pyroelectric effect and a parameter relating to an electric field inside the electrooptic crystal member;
A second electrode portion attached to the electro-optic crystal member so as to face the first electrode portion across the optical path of the detection light ;
The object is an electric field transmission medium, and is induced when an electric field for generating the electro-optic effect is induced in the electric field transmission medium in a state where the first electrode portion is in contact with the electric field transmission medium. A temperature sensor, wherein the electric field is applied to the first electrode portion via the electric field transmission medium. The temperature sensor according to any one of claims 1 to 3, wherein the parameter is a magnitude of polarization generated in the electro-optic crystal member. The object comes into contact with the insulating coating member, and the temperature change of the object is transmitted to the electro-optic crystal member via the insulating coating member and the first electrode, and the pyroelectric effect of the electro-optic crystal member The magnitude of the spontaneous polarization changes according to the temperature change of the object, and the potential difference between the first electrode portion and the second electrode portion changes according to the change in the spontaneous polarization, and the detection light 5. The apparatus according to claim 1 , further comprising a detecting unit that detects a phase difference of the detected light when the phase difference changes and detects the temperature change based on the detected phase difference. The temperature sensor according to any one of claims. A temperature sensor using an electro-optic effect that detects a temperature change of an object using a phase difference of a plurality of detection lights according to the electro-optic effect,
A plurality of first electrodes arranged so that each one end face is located on the same plane;
An insulative covering member that can contact the object and that respectively covers one end surfaces of the plurality of first electrodes;
A plurality of electro-optic crystal members disposed adjacent to the plurality of first electrodes on the optical paths of the plurality of detection lights, each having the electro-optic effect and the pyroelectric effect;
Information representing the relationship between the temperature of each of the plurality of electro-optic crystal members corresponding to the pyroelectric effect of each of the plurality of electro-optic crystal members and the parameter relating to the electric field generated in each of the plurality of electro-optic crystal members is stored. A temperature electric field related information storage unit;
A plurality of second electrodes attached to the plurality of electro-optic crystal members so as to face each of the plurality of first electrodes across the optical paths of the plurality of detection lights;
A temperature sensor comprising:

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