KR20070018059A - Target material sensor using photonic crystal and detection method for target material - Google Patents

Abstract

Provided are a target material sensor using a photonic crystal and a method for detecting the target material, which have high sensitivity to the detection target material and can be miniaturized.

The sensor of the present invention is composed of an electromagnetic wave generating source for supplying electromagnetic waves, a photonic sensor element, and a detector. The photonic sensor element has a photonic crystal structure, and includes a sensor waveguide for introducing electromagnetic waves and a sensing resonator for resonating electromagnetic waves introduced by electromagnetic coupling to the sensor waveguide at a specific wavelength. The sensing resonator changes the characteristics of electromagnetic waves emitted from the sensing resonator by being exposed to the atmosphere containing the target material. The detector receives an electromagnetic wave emitted from the sensing resonator, recognizes a change in intensity of the electromagnetic wave, and outputs a signal representing a characteristic of the target material.

Electromagnetic wave source, photonic sensor element, detector, sensor waveguide, sensing resonator

Description

Target material sensor using photonic crystal and detection method of target material {TARGET MATERIAL SENSOR USING PHOTONIC CRYSTAL AND DETECTION METHOD FOR TARGET MATERIAL}

The present invention relates to a sensor of a target substance using a photonic crystal and a method of detecting the target substance.

Prior art publication "Photonic Crystals" by R. Wehrspohn, ISBN3-527-40432-5, p. 238-246 discloses sensors using photonic crystals. The sensor uses a bulk three-dimensional photonic crystal as a sensor element, introduces a gas to be detected from one surface in the thickness direction of the sensor element, and simultaneously enters light having a wavelength matching the absorption wavelength of the gas to be detected, In addition, the light emitted from the surface is detected by a detector such as a photodetector, and the density is calculated according to the detected light intensity.

In general, if the group velocity of electromagnetic waves propagating in the photonic crystal is Vg, the propagation constant is β and the frequency is ω, the group velocity Vg is defined as Vg = (dβ / dω) ⁻¹ . . Therefore, the group speed Vg becomes smaller as the change ratio of the frequency ω to the change of the propagation constant β becomes smaller, and becomes zero when the relationship between the frequency ω and the propagation constant β becomes a standing wave condition (end condition of the waveguide mode). Becomes

In the sensor disclosed in the above publication, the optical path length is increased by designing the group velocity Vg of the light propagating the three-dimensional photonic crystal to a value of about 30% of the luminous flux in the vacuum, and therefore the thickness of the three-dimensional photonic crystal (that is, the optical The dimension of the direction along the direction of incidence should be several centimeters. As a result, a 100 nm order refractive index periodic structure that satisfies the condition of the frequency? And the propagation constant? For obtaining the intended group speed needs to be produced uniformly throughout the three-dimensional photonic crystal. However, when the refractive index periodic structure is distorted, the group velocity Vg deviates from the design value at that portion and accurate concentration measurement becomes impossible. Therefore, three-dimensional photonic crystals need to be manufactured with very precise manufacturing techniques.

In addition, since the three-dimensional photonic crystal has a relatively large thickness, the propagation mode is multi-mode, and the group speed is slow and the mode fast, so that the sensitivity is lower than in the case where the group speed is constant. There is a risk of deterioration. In addition, since the sensitivity is scattered with respect to the incident light to the three-dimensional photonic crystal because the coupling efficiency to various modes is not constant, high positional accuracy is required for the relative positional relationship between the light source and the three-dimensional photonic crystal. .

In addition, the spatial electric field intensity distribution by the slow light of the group speed Vg is significantly different from the Gaussian distribution which is the electric field intensity distribution of general spatial light. Therefore, the coupling loss of light occurs in the plane of incidence of light in the three-dimensional photonic crystal, resulting in a decrease in sensitivity. In some cases, complex coupling structures are needed to transform the field strength distribution.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a target material sensor using a photonic crystal and a method for detecting the target material, wherein the sensitivity to the detection target material is high and can be miniaturized. .

The sensor according to the present invention is composed of an electromagnetic wave generation source for supplying electromagnetic waves, a photonic sensor element, and a detector. The photonic sensor element has a photonic crystal structure and includes a sensor waveguide for introducing electromagnetic waves and a sensing resonator for electromagnetically coupling the sensor waveguide to resonate the introduced electromagnetic waves with a specific wavelength. The sensing resonator is exposed to an atmosphere including a target material to change characteristics of electromagnetic waves emitted from the sensing resonator. The detector receives the electromagnetic wave emitted from the sensing resonator, recognizes a change in intensity of the electromagnetic wave, determines a characteristic of the target material from the change in intensity, and outputs a signal representing the characteristic. In the sensor configured as described above, the characteristic of the target material can be detected according to the intensity of the electromagnetic wave emitted from the resonator by using the resonance of the electromagnetic wave of the specific wavelength generated in the resonator formed in the photonic crystal. As a result, the photonic sensor element can utilize a two-dimensional photonic crystal in which the sensor waveguide and the sensing resonator are disposed, and thus can be thinned. In addition, a portion where a precise photonic crystal structure is required is smaller than a sensor element using a photonic crystal having a conventional three-dimensional structure, leading to a reduction in manufacturing cost.

Preferably, the detector is configured to determine the concentration of the target material from the change in the characteristics of the electromagnetic waves and output a signal indicative of this concentration.

In the detection of the concentration of the target substance, the method differs depending on the case where the target substance uses the phenomenon of absorbing electromagnetic waves of a specific wavelength and when the wavelength of the electromagnetic wave output from the resonator is shifted due to the presence of the target substance. This is used.

In the configuration using the phenomenon in which the target material absorbs electromagnetic waves of a specific wavelength, a photonic sensor element in which a reference waveguide and a reference resonator are added is used in the photonic crystal structure. This reference waveguide introduces the electromagnetic wave from the electromagnetic wave source. The reference resonator electromagnetically couples to the reference waveguide, thereby resonating the introduced electromagnetic wave to the specific wavelength. The detector refers to an output intensity meter for outputting a detection signal representing the intensity of the electromagnetic wave of the specific wavelength from the sensing resonator, and a reference intensity meter for outputting a reference signal representing the intensity of the electromagnetic wave emitted from the reference resonator and the detection signal. Compared with a signal, the attenuation amount of the electromagnetic wave of the said specific wavelength is calculated | required, and it is comprised by the density meter which calculates the density | concentration of a target substance from this attenuation amount. Therefore, by setting the wavelength of the electromagnetic wave resonating with the sensing resonator to match the wavelength of the electromagnetic wave absorbed by the target material, the concentration of the target object corresponds to the amount of attenuation of the electromagnetic wave at a specific wavelength by using the absorption characteristics of the electromagnetic wave represented by the target material. In this way, concentration detection can be performed with good accuracy.

In this case, the photonic sensor elements have a photonic crystal structure arranged in a two-dimensional array, and the sensor waveguide and the reference waveguide respectively extend in the two-dimensional photonic crystal structure to form input ports and output ports at both ends. Do. Each input port is arranged to receive electromagnetic waves from an electromagnetic wave source, and each output port is coupled to the output intensity meter and the reference intensity meter, respectively. The output intensity meter and the reference intensity meter output electromagnetic waves emitted from respective corresponding sense resonators and reference resonators.

A sensing resonator and a reference resonator are disposed in the sensor waveguide and the reference waveguide. In addition, by arranging a plurality of resonators in series in each waveguide, it is preferable to increase the drop efficiency, which is the output efficiency of the output electromagnetic waves, and to increase the detection sensitivity.

The photonic sensor element may be formed to include a sensing output waveguide and a reference output waveguide. The sensed output waveguide and the reference output waveguide respectively extend parallel to the corresponding sensor waveguide and reference waveguide, and are electromagnetically coupled to the sense resonator and the reference resonator, respectively. These sensing output waveguides and reference output waveguides respectively form an output port at one end in the longitudinal direction, and the output port is coupled to the output intensity meter and the reference intensity meter, respectively.

In addition, each of the output intensity meter and the reference intensity meter may be disposed spaced apart from the plane of the photonic sensor element so as to be coupled to the sensing resonator and the reference resonator, respectively, to receive electromagnetic waves emitted therefrom.

In addition, the input path of the electromagnetic waves to the sense resonator and the reference resonator can be shared. In this case, a photonic sensor element in which the first photonic crystal structure and the second crystal structure different from each other are horizontally aligned is used. The waveguide has an input waveguide extending from the first photonic crystal structure to the second photonic crystal structure and a first output waveguide extending within the first photonic crystal structure and a second output extending within the second photonic crystal structure. It consists of a waveguide. A sense resonator is formed in the first photonic crystal structure and a reference resonator is formed in the second photonic crystal structure. The reference resonator is designed to resonate the electromagnetic wave at a wavelength λ2 different from the specific wavelength λ1 inherent to the sense resonator. According to this configuration, by making the first wavelength λ 1 of the electromagnetic wave resonating with the sensing resonator the wavelength of the electromagnetic wave absorbed by the target material, the electromagnetic wave of the second wavelength λ 2 resonating with the reference resonator is not affected by the target material. It is not necessary to shield the reference resonator from the atmosphere in which the target material is contained.

In another preferred embodiment of the present invention, a structure for measuring the concentration of the target substance is realized by using a phenomenon in which the refractive index around the resonance portion changes due to contact with the target substance. When the refractive index around the resonator changes, the wavelength of the electromagnetic wave resonating in the resonator shifts. In this case, since the change in the refractive index, that is, the shift amount of the resonance wavelength is uniquely determined by the target material, the concentration of the target material is determined by detecting the electromagnetic wave intensity of the wavelength shifted according to the target material. To realize this, electromagnetic waves containing different wavelengths are supplied from the electromagnetic wave generating source to the sensor waveguide, and electromagnetic waves of a specific wavelength corresponding to the type of target material cause resonance with the sensing resonator. In this case, the detector may measure the concentration of the target material by selecting the electromagnetic wave of the specific wavelength (electromagnetic wave of the wavelength changed by the presence of the target material) output from the sensing resonator and analyzing the electromagnetic wave intensity of the selected specific wavelength. This method is effective for the detection of a target substance for which absorption of electromagnetic waves at a specific wavelength is not recognized, and the reference resonator and the elements related thereto are unnecessary, so that a further miniaturized sensor can be realized.

In order to select the electromagnetic wave of a specific wavelength, a spectral function is required, but the structure which implements the system which does not require this spectral function is also possible. In this case, as an electromagnetic wave generation source, generating an electromagnetic wave of a variable wavelength is used, and the electromagnetic wave whose wavelength changes with time is introduced into a photonic sensor element. The sweep range of the wavelength is set so as to include a specific wavelength determined by the refractive index indicated by the target material, and the target is obtained by detecting the intensity of the electromagnetic wave from the resonator at the time when the electromagnetic wave of the specific wavelength is introduced from the electromagnetic wave source. The concentration of the substance can be measured.

In addition, the method of using the shift of the resonance wavelength in the sensing resonator is useful for detecting a plurality of kinds of target substances. That is, by arranging a plurality of one detection units comprising a sensor waveguide, a sensing resonator, and a detector, and making specific wavelengths of electromagnetic waves resonating with the sensing resonators in each detection unit different from each other, i. The concentrations of the different target substances can be obtained from the corresponding electromagnetic wave intensities.

As a means for actively causing or enhancing the wavelength shift depending on the target material in the sensing resonator, sensing a reactant that reacts with the object to give a significant change in the refractive index around the sensing resonator and likewise result in a significant wavelength shift. It is preferable to attach to the resonator.

In the case of using such a sensitive body, it is possible to attach the sensitive body to one of two sensing resonators provided in the photonic sensor element. In this case, by referring to the intensity of the synthesized electromagnetic wave radiated from the sense resonator without the sensitive body and the sense resonator with the sensitive body, the concentration of the target substance causing the reaction to the sensitive body is determined.

In the system using the shift of the resonance wavelength in the sensing resonator, the sensors can be easily constructed by setting the plurality of sensing resonators in a two-dimensional array. In this case, the plurality of object detectors are arranged two-dimensionally in a manner to match the plurality of sensing resonators, whereby different concentrations are determined for each object detector, and the concentration distribution of the target substance in the two-dimensional plane can be obtained.

In addition to the concentration of the target substance, it is also possible to detect different kinds of target substances dispersed in a range up to a certain range. In this case, the plurality of sensing resonators are arranged in a two-dimensional array, and correspondingly, the plurality of detectors are arranged in a two-dimensional array. The plurality of sensing resonators are set to resonate with electromagnetic waves of different specific wavelengths, respectively, so that the plurality of detectors can specify the presence of different target materials according to the intensity of the electromagnetic waves of a specific wavelength emitted from the sensing resonators, and in-plane The distribution of different target substances in can be obtained.

In addition, the present invention discloses a useful structure for determining the concentration of a target material in accordance with a change in electromagnetic wave intensity generated by disposing a sensitive body in a portion other than the sensing resonator. For example, by placing a sensitizer in a sensor waveguide and reacting with an object, the refractive index of the sensor waveguide changes, and the effective waveguide length between the sensor waveguide and the sensing resonator changes, and as a result, the electromagnetic wave intensity output to the detector. Brings change. The detector can calculate the concentration of the target material according to the change of the electromagnetic wave intensity.

In addition, if a sensitive body is placed at an energy coupling site between two sensing resonators arranged in a photonic sensor element, the effective waveguide length of the energy coupling site is changed in a similar manner by reaction with a target substance. The concentration of the target substance can be determined by analyzing the electromagnetic wave intensity generated.

Moreover, in this invention, the structure of the photonic sensor element for detecting a highly sensitive density | concentration is proposed by combining such a sensitive body with a special photonic crystal structure. The photonic sensor element has a first photonic crystal structure and a second photonic crystal structure, wherein the first and second photonic crystal structures are different from each other and are arranged side by side in a two-dimensional array. The sensor waveguide consists of an input waveguide and an output waveguide, wherein the input waveguide and the output waveguide extend in parallel with each other and each extend over the entire length of the first photonic crystal structure to reach the second photonic crystal structure. do. The sense resonator is disposed between the input waveguide and the output waveguide in the first photonic crystal structure and electromagnetically coupled to both. At one end in the longitudinal direction of the input waveguide, an input port for receiving electromagnetic waves from the electromagnetic wave generation source is formed at a distance from the second photonic crystal structure. At one end in the longitudinal direction of the output waveguide, away from the second crystal structure, an output port is formed that emits electromagnetic waves resonating at a particular wavelength in the sense resonator. In the input waveguide, at the interface between the first photonic crystal structure and the second photonic crystal structure, an input reflector for reflecting electromagnetic waves of a specific wavelength on the sensing resonator side is formed. In the output waveguide, an output reflector for reflecting electromagnetic waves of a specific wavelength on the output port side is formed at the interface between the first crystal structure and the second crystal structure. In each of the input waveguide and the output waveguide having such a configuration, the sensitive body is formed at a portion that connects the first photonic crystal structure and the second photonic crystal structure. The sensitizer changes the reflection efficiency by reacting with the target material, and as a result, changes the intensity of the electromagnetic wave in the target detector, and the detector calculates the concentration of the target material as a function of this intensity. In this way, the input waveguide and the output waveguide are designed to span different photonic crystal structures to form reflectors of electromagnetic waves at their interfaces, and the input waveguides and output waveguides at the input waveguide and output waveguides at the portions covering the different photonic crystal structures are formed. Since a sensitive body is provided to change the characteristics of the electromagnetic wave in response to the presence, the change of the refractive index in the reflector is emphasized by the presence of the target material, and the phase change of the electromagnetic wave propagating toward the sensing resonator can be generated. The drop efficiency of electromagnetic waves of a specific wavelength emitted by resonating with the sensing resonator may be increased, and the concentration of the target material may be measured with high sensitivity.

Moreover, in the sensor of this invention, it is preferable to provide the controller which monitors the environmental parameter which shows an environmental state. This controller corrects the optical characteristics of the sensing resonator in accordance with environmental parameters to resonate electromagnetic waves at a specific wavelength, thereby correcting disturbance factors such as temperature, thereby enabling accurate measurement. As an example, a heater is provided in the photonic sensor element, and the temperature of the sensing resonator is corrected by controlling by the controller to correct the optical characteristics of the photonic sensor element, thereby keeping the characteristics of the sensing resonator constant.

It is also preferable to provide refreshing means for removing the target substance or impurities replenished on the sensing resonator in the sensor of the present invention. As this means, a heater that releases a target substance or impurities from the resonator by heat can be used.

In addition, the above-mentioned heater can be used as a modulation means for modulating the wavelength or intensity of the electromagnetic wave which guides the waveguide. In other words, by flowing at a constant period to the heater, the intensity or wavelength of the electromagnetic wave emitted from the resonator is periodically modulated, and only the modulated electromagnetic wave is selected as the detector among the electromagnetic waves detected by the detector, thereby reaching the detector from other than the resonator. It can identify as an electromagnetic wave of noise, and can improve a measurement precision.

The present invention also provides a method for detecting the concentration of a target substance using photonic crystals. In this method, a photonic sensor element having a sensor waveguide for introducing electromagnetic waves and a sensing resonator electromagnetically coupled thereto to resonate electromagnetic waves of a specific wavelength is used, and the sensing resonator is exposed in an atmosphere containing a target material, By introducing an electromagnetic wave containing a wavelength into the sensor waveguide, it is possible to detect the intensity of the electromagnetic wave resonating in the sensing resonator, and analyze the intensity to calculate the concentration of the target substance.

1 is a schematic view showing a first embodiment of a sensor according to the present invention.

2 is a functional block diagram.

3 is a graph illustrating the concentration detection.

4 is a perspective view showing an example in addition to the photonic sensor element used above.

5 is a perspective view showing an example in addition to the photonic sensor element used above.

6 is a perspective view showing an example in addition to the photonic sensor element used above.

7 is a perspective view illustrating an example other than the photonic sensor element used above.

8 is a perspective view showing an example other than the photonic sensor element used above.

9 is a schematic view showing a second embodiment of a sensor according to the present invention.

10 is a schematic view showing a third embodiment of the sensor according to the present invention.

11 is a functional block diagram.

12 is a graph illustrating concentration detection from above.

It is a perspective view which shows the photonic sensor element used from above.

14 is a partially enlarged top view of a portion including the sensing resonator shown in FIG. 13.

FIG. 15 is a partially enlarged cross-sectional view of a portion including the sensing resonator illustrated in FIG. 13.

16 is a perspective view illustrating an example other than the photonic sensor element used above.

17 is a perspective view illustrating an example other than the photonic sensor element used above.

18 is a perspective view illustrating an example other than the photonic sensor element used above.

19 is a perspective view illustrating an example other than the photonic sensor element used above.

20 is a perspective view showing an example in addition to the photonic sensor element used above.

Fig. 21 is a schematic diagram showing the fourth embodiment of the sensor according to the present invention.

Fig. 22 is a functional block diagram.

Fig. 23 is a schematic view showing the fifth embodiment of the sensor according to the present invention.

24 is a perspective view illustrating an example other than the photonic sensor element used above.

25 is a perspective view illustrating an example other than the photonic sensor element used above.

Fig. 26 is a schematic view showing the sixth embodiment of the sensor according to the present invention.

Best Mode for Carrying Out the Invention

The sensor according to the present invention uses a photonic sensor element 20 having a photonic crystal structure arranged in a two-dimensional array. The photonic crystal structure is a matrix and a material having a refractive index different from the matrix is arranged in the matrix, and has an optical characteristic that arbitrarily changes the direction and propagation speed of the incident electromagnetic wave. In the present invention, as an example, a silicon semiconductor (thickness = 250 nanometers) having a refractive index of 3.4 is used as a matrix, and fine circular holes (φ = 240 nanometers) are placed in two-dimensional phases at a pitch of 420 nanometers in the matrix. Arranged photonic crystals are used. As a result, air having a refractive index of 1 present in minute pores is periodically dispersed in the substrate (refractive index 3.4) to impart characteristics of the photonic crystal. This silicon semiconductor is mounted on the SOI substrate (refractive index 1.5) which is a silicon oxide layer. That is, the photonic crystal uses a SOI substrate to etch the silicon semiconductor layer on the surface to form a plurality of minute circular holes, thereby realizing the photonic crystal structure in the silicon semiconductor layer.

The photonic sensor element 20 is provided with a waveguide 22 of an electromagnetic wave to be input and a resonator 24 for resonating a specific wavelength among the electromagnetic waves introduced into the waveguide. These waveguides and resonators are formed by imparting a defect to the periodic structure in the photonic crystal structure, that is, providing a portion where no hole exists.

When the frequency band uses an optical communication band such as the C band (1530 nm-1565 mm) or the L band (1565 nm-1625 nm) as the electromagnetic wave, the arrangement period (a) of the circular hole in the two-dimensional photonic crystal (1) is 0.42. m (i.e., the period of the refractive index periodic structure of the two-dimensional photonic crystal or the lattice distance between the lattice points of the two-dimensional triangular lattice), the radius of the circular hole is set to 0.29a and the thickness of the sensor element is set to 0.6a. This forms a photonic band gap which is a wavelength band which does not propagate electromagnetic waves (light) in the frequency band incident from all directions in the two-dimensional plane orthogonal to the thickness direction of the photonic crystal .. Waveguide 22 and Resonator 24 The propagation of electromagnetic waves formed by omitting an appropriate number of circular holes is possible, and the numerical values of the period (a) in the arrangement direction of the circular holes and the radius of the circular hole are not particularly limited, and the period (a) is Prize Electromagnetic wave level of the frequency band is the period of the (e. G., About one-half of the wavelength of the electromagnetic wave).

The present invention performs concentration detection of a target substance by using the resonance phenomenon of electromagnetic waves in a resonator in such a photonic crystal, and performs concentration detection by a different mechanism depending on the type of the target substance to be measured. The target substance can be broadly divided into two types.

1) The property of absorbing electromagnetic waves of a specific wavelength is remarkable.

2) The property of changing the refractive index of the atmosphere is remarkable.

In the present invention, the above two properties are used depending on the substance to be measured, and a first embodiment in which concentration detection using the property of 1) is realized will be described.

<First Embodiment>

In this embodiment, the electromagnetic wave of a specific wavelength absorbed by the target material is resonated by a resonator, and the concentration of the target material is measured from the attenuation rate of the output. As a target substance, the thing which remarkably absorbs the electromagnetic wave of a specific wavelength, for example, gas, such as a carbon dioxide gas and nitrogen gas, is applied.

1 and 2 show a sensor according to the present embodiment, and the photonic sensor element 20 includes a sensor waveguide for guiding an electromagnetic wave including a specific wavelength, for example, an infrared ray including a wavelength of 2 μm to 13 μm ( 22 and the reference waveguide 32 as well as the sense resonator 24 and the reference resonator 34 which are electromagnetically coupled with these waveguides are formed. Each resonator is designed to resonate the electromagnetic waves of the particular wavelength (absorbed in the target material). The sensing resonator 24 and the sensor waveguide 22 are exposed to the atmosphere containing the target substance and measure the intensity of the electromagnetic wave absorbed by the presence of the target substance. On the other hand, the reference waveguide 32 and the reference resonator 34 are shielded from the atmosphere containing the target substance by the shield 36 to obtain the reference intensity of the electromagnetic wave, and to obtain the attenuation rate of the electromagnetic wave from the difference between the two intensities. The concentration of the target substance is determined from this decay rate.

In order to achieve this function, the sensor according to the present embodiment includes an electromagnetic wave source 10 for supplying the photonic sensor element 20 and a distributor for branching the electromagnetic wave to the sensor waveguide 22 and the reference waveguide 32. (11), the output intensity meter 41 which detects the intensity of the electromagnetic wave emitted from the sensing resonator 24, the reference intensity meter 51 which detects the intensity of the electromagnetic wave emitted from the reference resonator 34, A densitometer 42 is provided for determining the concentration of the target substance by determining the attenuation rate of the electromagnetic waves from the difference in the electromagnetic wave strengths to be obtained. These output intensity meters 41, reference intensity meters 51 and densitometers 42 are collectively referred to as detectors 40 to be realized in a single microprocessor. The detector 40 outputs a concentration signal indicating the concentration obtained by the densitometer 42 to the display 60 to display the concentration of the target substance.

The sensor waveguide 22 and the reference waveguide 32 extend in a straight line along the entire length of the photonic sensor element 10 in the longitudinal direction, with one end in the longitudinal direction as the input ports 21 and 31, and the other end. The output ports 23 and 33 are respectively used. An injector 12 is coupled to the input ports 21 and 31, respectively, to introduce electromagnetic waves from the electromagnetic wave generation source into each waveguide. The output ports 23 and 33 are respectively coupled to the output intensity meter 41 and the reference intensity meter 51 so as to transmit electromagnetic waves of a specific wavelength emitted from the sensing resonator 24 and the reference resonator 34 to these intensity meters. Output The sensing resonator 24 and the reference resonator 34 are formed in the center of the longitudinal direction in each waveguide, and propagate electromagnetic waves resonating with the resonators to the output ports 23 and 33. The output intensity meter 41 outputs a detection signal indicating the intensity of electromagnetic waves resonating in the resonator 24, while the reference intensity meter 51 outputs a reference signal indicating the intensity of electromagnetic waves resonating in the resonator 34. . The densitometer 42 calculates the attenuation rate of the electromagnetic wave intensity caused by the presence of the target substance from the difference between the detection signal from the output intensity meter 41 and the reference signal from the reference detector. This attenuation rate is expressed by the following equation (1).

Here, Iref is the output of the reference intensity meter 51 and Iout is the output from the output intensity meter 41.

The relationship as shown in FIG. 3 is recognized between the damping rate L thus obtained and the absorption coefficient of the target substance. The absorption coefficient corresponds to the concentration of the target substance in the atmosphere, and since the expression indicating the relationship between the decay rate and the concentration is prepared in the detector 40, the concentration of the target substance is determined by the densitometer 42 from the decay rate. And the output intensity of an electromagnetic wave is determined by following formula (2).

Qin is a Q value determined by the coupling strength of light between the resonator and the waveguide, and a Q value determined by the amount of energy lost by absorption in the Qatar resonator. More specifically, the Q value between the resonator and the waveguide is Qin, and the Q value due to absorption in the resonator is Qa, and the Q value between the resonator and the free space is Qy, and Qy''Qin. Qin is a value relating to the amount of energy leaking from the resonator to the waveguide in the system between the resonator and the waveguide (that is, a value indicating how much energy can be accumulated in the resonator in the system between the resonator and the waveguide). When the energy accumulated in the resonator is W and the energy lost to the waveguide side from the resonator in unit time is dW / dt, Qin = ω ₀ x W / (dW / dt). Qa is a value relating to the amount of energy lost by absorption in the resonator. When Qa is stored in the resonator and energy is lost in unit time due to absorption in the resonator, Qa is Qa. = (ω ₀ x n _m ) α x c), where n _m is the effective refractive index of the resonator 24, α is the absorption coefficient of the resonator, and c is the luminous flux in vacuum.

However, the output intensity of the electromagnetic wave, is known as the drop efficiency (D), by the ratio of the electromagnetic wave intensity S ₊₂ is output from the electromagnetic wave intensity S _{+ 1} and the output port is input to the input port as represented by the following formula: Is expressed.

In the method shown in Fig. 2, a controller 70 is provided which monitors the intensity of the electromagnetic wave output from the electromagnetic wave source 10 and makes this output intensity constant by feedback control, thereby correcting fluctuation caused by disturbance. The measurement is to be performed.

In addition to the structure shown in FIG. 1, the photonic sensor element can use what was shown in FIGS. In these figures, only the structures related to the sensor waveguide 22 and the sensing resonator 24 are described for the sake of simplicity, but the same configuration can be applied to the reference waveguide and the reference resonator.

In the photonic sensor element 20 shown in FIG. 4, a plurality of sensing resonators 24 are formed in the sensor waveguide 22, and both ends of the sensor waveguide in the longitudinal direction are respectively input ports 21 and output ports ( 23). Each sensing resonator 24 is designed to resonate electromagnetic waves of the same specific wavelength, thereby increasing the chance of contact with the target material, thereby increasing the detection sensitivity of the target material.

In the photonic sensor element 20 shown in FIG. 5, the heater 80 is integrally formed, and the optical characteristic of the photonic sensor element is kept constant by temperature control by the heater 80, thereby making it an accurate object. The concentration measurement of a substance can be performed. This temperature control is performed by the controller shown in FIG. 2 using a temperature sensor. The heater 80 can be used to dissipate objects or impurities attached to the sensing resonator by heat in addition to this purpose. By heating with a heater at an appropriate timing, the sensor element can be refreshed. As the heater, one using a Peltier element is preferable.

In addition, the above-mentioned heater can be used as a modulation means for modulating the wavelength or intensity of the electromagnetic wave which guides the waveguide. In other words, by flowing at a constant period of the heater, the intensity or wavelength of the electromagnetic wave emitted from the resonator is periodically modulated, and only the modulated electromagnetic wave is selected by the analyzer from among the electromagnetic waves detected by the detector to reach the detector from other than the resonator. It can distinguish from electromagnetic waves of noise and improve measurement accuracy. The modulating means is not limited to a heater, and may be any one that performs wavelength modulation or intensity modulation of electromagnetic waves output from an electromagnetic wave source, for example, a chopper rotating plate and a corresponding chopper for periodically blocking the output of the electromagnetic wave source. Modulation means may be constituted by a drive motor of the rotating plate to control the drive motor by the control circuit.

In the photonic sensor element 20 shown in FIG. 6, the sensor waveguide is comprised by the input waveguide 22A and the output waveguide 22A which extend in parallel with each other. The sensing resonator 24 is formed between the input waveguide 22A and the output waveguide 22B and receives an electromagnetic wave of a specific wavelength from the electromagnetic wave input from the input port 21 at one end of the input waveguide 22A. Read and resonate here. This electromagnetic wave propagates through the output waveguide 22B and is output from the output port 23 formed at one end in the longitudinal direction to the detector.

In the photonic sensor element 20 shown in FIG. 7, the input port 21 and the output port 23 are formed at both ends of the sensor waveguide 22 in the longitudinal direction, and the photonic sensor element 20 is formed from the sensor waveguide 22. The sensing resonator 24 is formed in a portion spaced apart along the width direction of the sensor, that is, a portion spaced in a direction orthogonal to the longitudinal direction of the sensor waveguide, and the electromagnetic waves emitted from the sensing resonator 24 are output ports 23. It is output to the detector through.

In the photonic sensor element 20 shown in FIG. 8, the detector is designed to emit electromagnetic waves from the sensing resonator 24 in the thickness direction of the photonic sensor element 20, and the detector disposed above the sensing resonator 24; Electromagnetic coupling.

In the above embodiment, the concentration of one kind of target substance is measured by one detection unit composed of the sensor waveguide 22, the sensing resonator 24, and the detector 40. Therefore, when a plurality of detection units are provided in correspondence with different target substances, the concentration of the different target substances can be measured. In this case, a plurality of sensing resonators for resonating electromagnetic waves of different wavelengths and a plurality of sensor waveguides corresponding thereto are formed in one photonic sensor element.

Second Embodiment

9 shows a second embodiment of the present invention. In this embodiment, the configuration of the photonic sensor element 20 designed to supply the electromagnetic wave from the electromagnetic wave source 10 to the sensing resonator 24 and the reference resonator 34 through a single input port 21 is shown. . In this photonic sensor element 20, a first photonic crystal structure PC1 and a second photonic crystal structure PC2 having different crystal structures are formed. That is, in the two crystal structures, microcircular holes for changing the refractive index are two-dimensionally arranged at different periods, thereby making it possible to selectively propagate electromagnetic waves of different wavelengths. The sensor waveguide consists of one input waveguide 22A extending over two crystal structures PC1 and PC2 and two output waveguides 22B1 and 22B2 inherent to each crystal structure, and in each crystal structure PC1 and PC2, A sensing resonator 24 and a reference resonator 34 are electromagnetically coupled to the input waveguide 22A and the output waveguides 22B1 and 22B2, respectively. Each photonic crystal structure PC1, PC2 is designed such that electromagnetic waves of different wavelengths resonate with each of the resonators 24, 34. [0035] FIG. That is, the first photonic crystal structure PC1 is designed to resonate with the electromagnetic wave of the first wavelength? 1 absorbed by the target material, and the second photonic crystal structure PC2 is designed to resonate with the other second wavelength? 2, Using the detector 40 similar to that shown in FIGS. 1 and 2, the intensity of the electromagnetic wave of the first wavelength λ 1 is detected by the output intensity meter 41, and the electromagnetic wave of the second wavelength λ 2 is detected. The intensity is detected by the reference intensity meter 51. The densitometer 42 compares the electromagnetic wave intensity of the second wavelength [lambda] 2 and the electromagnetic wave intensity of the first wavelength [lambda] 1 to obtain the attenuation rate of the electromagnetic wave intensity of the first wavelength [lambda] 1. In the same manner, the concentration of the target substance is calculated.

In the present embodiment, the first wavelength λ1 of the electromagnetic wave resonating by the sensing resonator 24 is set as the wavelength of the electromagnetic wave absorbed by the target material, and the second wavelength of the electromagnetic wave resonating by the reference resonator 34 ( Since lambda 2) is set to be different from the first wavelength, electromagnetic waves resonating with the reference resonator 34 are not affected by the target material. Therefore, it is not necessary to shield the reference resonator 34 from the atmosphere containing the target material.

Third Embodiment

10 and 11 disclose a manner in which the property of changing the refractive index of the atmosphere is realized for the measurement of a significant target material. Examples of the target material in this case include water vapor, alcohol, and the like, and the refractive index around the sensing resonator changes due to the presence of the target material to shift the wavelength resonating to the sensing resonator. The concentration measurement is performed. 12 shows the relationship between the refractive index indicated by the target material and the wavelength of electromagnetic waves generated in the resonator determined accordingly. Therefore, by designing the sensing resonator to resonate at a specific wavelength determined by the target material, the concentration of the target material can be grasped as a change in the output intensity emitted from the sensing resonator 24.

For this purpose, in this embodiment, a wideband electromagnetic wave including a specific wavelength is introduced into the sensor waveguide 22, and from the electromagnetic wave output from the sensing resonator 24, an electromagnetic wave of a specific wavelength inherent to the target material is introduced. The strength is withdrawn selectively, and the concentration of the target substance is calculated according to this strength. In the photonic sensor element 20 of the embodiment shown in the figure, the sensor waveguide is composed of two parallel extending input waveguides 22A and output waveguides 22B, and a sensing resonator 24 is formed between both waveguides. . The sensing resonator 24 is exposed to an atmosphere containing the target substance and, when contacted with the target target substance, of the electromagnetic wave introduced into the input port 21 at one end in the longitudinal direction of the input waveguide 22A, the target substance Electromagnetic waves having a wavelength intrinsic to the resonator 24 are resonated by the resonator 24, and the resonant electromagnetic waves are output to the detector 40 through one end of the output port 23 in the longitudinal direction of the output waveguide 22B.

The detector 40 has a spectroscopic analysis function, selects an electromagnetic wave of a specific wavelength determined by a target substance by spectroscopy, obtains the electromagnetic wave intensity, and determines the concentration of the target substance as proportional to the electromagnetic wave intensity. A concentration signal indicating the concentration of the target substance is output. The display 60 receives this concentration signal and displays the concentration.

The electromagnetic wave source 10 supplies a wideband electromagnetic wave including a wavelength determined by a target substance, for example, an infrared ray including a wavelength of 2 µm to 13 µm.

13 to 20 show a number of variations on the photonic sensor element 20 used in the third embodiment described above.

In the modified embodiment of FIGS. 13 to 15, a sensing body 80 is arranged on the sensing resonator 24 to change the wavelength of electromagnetic waves resonating in the sensing resonator 24 by adsorbing or reacting with a target material. . The sensitizer 80 is for actively causing or enhancing the wavelength shift according to the target material, and is made of a material that greatly varies the refractive index around the resonator 24 due to the presence of the target material. For example, in the case of realizing a humidity sensor using water as the target material, a material that adsorbs water such as SiO ₂ or a polymer is used, and in the case of realizing a biosensor in which the target material is an ecological material, A receptor such as is used as the material. M in FIG. 14 schematically shows molecules of the target substance adsorbed by the sensitizer 80.

In the modified embodiment of FIGS. 16 to 18, two resonators 24A and 24B are formed in the photonic sensor element 20, and the above sensitive body 80 is provided only in one resonator 24A. If the target substance is present, the wavelength of the electromagnetic wave resonating with one resonator 24A is shifted from the wavelength of the electromagnetic wave resonating with the other resonator 24B, so that the electromagnetic coupling force between both resonators is weakened. The intensity of the electromagnetic wave output to 40 changes. The detector 40 recognizes the change in the electromagnetic wave intensity and determines the concentration of the target substance according to the change degree. In the detector 40, the concentration is determined in accordance with the change in the output intensity of the electromagnetic wave resonating with the resonator provided with the sensitizer. However, the detector 40 is used for the output intensity of the electromagnetic wave resonating with the resonator without the sensitizer. You may also

16, the example which arrange | positioned the two resonators 24A and 24B in the width direction of the photonic sensor element 20 between the two input waveguides 22A and the output waveguide 22B is shown. Indicates. 17 shows an example in which two resonators 24A and 24B are disposed along the longitudinal direction of the waveguide 22 outside one waveguide 22. 18 shows an example in which two resonators 24A and 24B are arranged and arranged in the center of one waveguide 22.

In the modified embodiment of FIG. 19, a plurality of pairs of the waveguide 22 and the resonator 24 are formed in the photonic sensor element 20, and the electromagnetic wave generating source 10 and the detector 40 are provided in accordance with each pair. . Each resonator 24 is designed to resonate electromagnetic waves of different wavelengths to measure the concentration of a plurality of kinds of target materials. In this case, it is possible to provide the above-described sensitive body in at least one resonator 24.

In the modified embodiment of FIG. 20, in the photonic sensor element 20, a plurality of mutually parallel waveguides 22 are formed along one direction, and the plurality of resonators 24 are vertically and horizontally arranged in a two-dimensional surface to form a surface sensor. To form. Each waveguide 22 is supplied with electromagnetic waves from a single electromagnetic wave source 10, and a detector 40 is coupled to each resonator 24. The detector 40 is likewise arranged in a two-dimensional plane and supported by the frame 90. The detectors 40 are spaced apart from each other in a direction perpendicular to the plane in which the resonators 24 are arranged, and the electromagnetic waves emitted from the resonators 24 are output to the detector 40. Each resonator 24 is electromagnetically coupled to adjacent waveguides 22 and is designed to resonate electromagnetic waves having different wavelengths, thereby recognizing a change in refractive index in the plane, that is, a change in a target material in the plane. can do. That is, the intensity of the electromagnetic wave output from the different resonators 24 shows the concentration of the different target materials, and for example, the progress of the reaction caused by the target materials can be detected. Therefore, in addition to the detection of the concentration, the distribution of different target substances in the plane can be obtained. If the plurality of resonators 24 are designed to resonate electromagnetic waves of the same wavelength, the concentration distribution in the plane of the specific target material can be obtained. Moreover, in this modification aspect, a sensitive body can also be provided in a resonator.

Fourth Example

21 and 22 show a fourth embodiment of the present invention. This embodiment is basically the same as the third embodiment, but uses an electromagnetic wave source of supplying a variable wavelength as the electromagnetic wave source 10, and performs a wave sweep to detect an electromagnetic wave whose wavelength changes with time. Introduced into element 20. The sweep range of the wavelength is set to include a specific wavelength determined by the refractive index indicated by the target material, and the intensity of the electromagnetic wave from the resonator 24 when the electromagnetic wave of the specific wavelength is introduced from the electromagnetic wave source 10. By obtaining from the detector 40, the concentration of the target substance can be measured. Therefore, in the present embodiment, a sweep controller 46 is provided to change the wavelength from the electromagnetic wave source 10 over time and to change the wavelength of the reading of the electromagnetic wave output from the detector 40. Motivated by In the concentration measurement, the output intensity of the electromagnetic wave of a wavelength different from the specific wavelength corresponding to the target substance is stored as the reference intensity, and the output intensity of the electromagnetic wave of the specific wavelength corresponding to the target substance is compared with this reference intensity. The concentration of is obtained by calculation. According to this configuration, the electromagnetic wave intensities can be individually analyzed at various wavelengths within the sweep range of the wavelength, and therefore concentrations for different kinds of target substances can be obtained. The configuration of the photonic sensor element 20 used in this embodiment is applicable to the configuration shown in FIGS. 5 to 8 and 13 to 18 in addition to the configuration shown in FIG. 21.

It is also possible to apply the present embodiment to a configuration in which the measurement accuracy is increased by periodically modulating the electromagnetic wave intensity emitted from the resonator as described above or periodically modulating the electromagnetic wave intensity supplied from the electromagnetic wave source to the resonator.

Fifth Embodiment

23 shows a fifth embodiment of the present invention. In this embodiment, the above-described sensitive body 80 is disposed in the electromagnetic path passing through the resonator 24 in the photonic sensor element 20. When the sensitizer 80 adsorbs or reacts with the target material, the electromagnetic wave detected by the detector 40 due to the change of the electromagnetic coupling efficiency in the electromagnetic wave path (energy coupling path), that is, the effective waveguide length, Since the intensity changes, the concentration of the target substance is measured according to the change of the electromagnetic wave intensity. In this embodiment, a resonator (80) is formed in the center of the waveguide (22) having both ends of the input port (21) and the output port (23), and formed in correspondence with the center of the waveguide ( The electromagnetic bond strength with 24) is changed by the presence of the target substance.

FIG. 24 shows a modification of the fifth embodiment, in which a sensitizer 80 is formed between two resonators 24 arranged in parallel with the waveguide 22 in the photonic sensor element 20, thereby providing two resonators. The concentration of the target substance is detected by the change of the electron coupling efficiency therebetween.

FIG. 25 shows a modification of the fifth embodiment, between the two resonators 24 arranged in the photonic sensor element 20, between two parallel input waveguides 22A and output waveguides 22B. The sensitizer 80 is formed, and the concentration of the target substance is detected by the change of the electron coupling efficiency between the two resonators.

Sixth Embodiment

Fig. 26 shows the sixth embodiment of the present invention. In the photonic sensor element 20 used in this embodiment, the first photonic crystal structure PC1 and the second photonic crystal structure PC2 having different crystal structures are successively formed. In these two crystal structures, minute circular holes for changing the refractive index are two-dimensionally arranged at different periods, thereby making it possible to selectively propagate electromagnetic waves of different wavelengths. The incident waveguide 22A and the output waveguide 22B are formed to be connected across the first photonic crystal structure PC1 and the second photonic crystal structure PC2, respectively, and the input waveguide 22A is provided at one end of the first crystal structure PC1. An electromagnetic wave input port 21 is formed, and an electromagnetic wave output port 23 is formed in the output waveguide 22B. The resonator 24 is disposed between the input waveguide 22A and the output waveguide 22B in the first photonic crystal structure PC1 and is electromagnetically coupled with both. The resonator 24 is designed to resonate electromagnetic waves of a specific wavelength.

In the input waveguide 22A, at the interface between the first photonic crystal structure PC1 and the second photonic crystal structure PC2, an input reflector that reflects only electromagnetic waves of a specific wavelength resonating with the resonator and passes the remaining wavelength components ( 25A) is formed. Similarly, at the interface between the first photonic crystal structure PC1 and the second photonic crystal structure PC2 in the output waveguide 22B, only electromagnetic waves of a specific wavelength resonating with the resonator 24 are reflected, and the remaining wavelength components An output reflector 25B that passes through is formed. Such a reflector is formed in accordance with the difference in the periodic structure between the first photonic crystal structure PC1 and the second photonic crystal structure PC2, and electromagnetic waves of a specific wavelength allowed to be resonance by the resonator 24 are separated from the input waveguide 22A. The efficiency of propagating to the resonator 24 and the efficiency of outputting the electromagnetic wave of a specific wavelength causing resonance to the resonator 24 to the detector 40 via the output waveguide 22B are improved.

In the input waveguide 22A and the output waveguide 22B, the sensitizer 80 described above is formed in a portion covering the first photonic crystal structure PC1 and the second photonic crystal structure PC2, and reacted with the target substance. By changing the performance of the interface of both crystal structures, the functions at the input reflector 25A and the output reflector 25B are changed, and the reflection function of the electromagnetic wave of a specific wavelength which resonates with the resonator 24 is greatly reduced. Therefore, when the sensitive body 80 acknowledges the presence of the target substance, the electromagnetic wave intensity of the specific wavelength output from the output waveguide 22B is lowered, and the concentration of the target substance can be calculated from the change of the electromagnetic wave intensity. That is, drop efficiency D is calculated | required from the electromagnetic wave intensity input into the detector 40, and density | concentration is calculated | required from this drop efficiency. The drop efficiency D is a ratio between the input electromagnetic wave strength S _{+ 1} and the output electromagnetic wave strength S- ₂ expressed by the formula (3).

Drop efficiency (D) is also expressed by the following equation.

In the above formula,

d ₁ is a distance between the resonator 24 and the input reflector 25A along the longitudinal direction of the input waveguide 22A,

d ₂ is a distance between the resonator 24 and the output reflector 25b along the longitudinal direction of the output waveguide 22A,

β ₁ is a propagation constant of the input waveguide 22A,

β ₂ is a propagation constant of the output waveguide 22B,

Δ ₁ is the change in reflection phase of electromagnetic waves reflected by the input reflector 25A,

Δ ₂ is a change in reflection phase of electromagnetic waves reflected by the output reflector 25B,

θ ₁ is an amount of phase change of electromagnetic waves reflected by the input reflector 25A and returned to the vicinity of the resonator 24,

θ ₂ is an amount of phase change of electromagnetic waves reflected by the output reflector 25B and returned to the vicinity of the resonator 24,

ω ₀ is the resonant frequency at the resonator 24,

Q _inb is the Q value between the resonator 24 and the input waveguide 22A,

Q _inr is the Q value between the resonator 24 and the output waveguide 22B,

W is the energy accumulated in the resonator 24,

dW / dt is energy lost in the unit time from the resonator 24 to the input waveguide 22A and energy lost in the unit time from the resonator 24 to the output waveguide 22B.

The photonic sensor element 20 in this embodiment forms a plurality of minute circular holes in a silicon semiconductor layer laminated on a SiO ₂ substrate to realize a photonic crystal structure, and the resonator 24 has circular holes. Is made of a donor-shaped defect formed by filling a circular hole with silicon, that is, a radiation loss in free space is reduced, so that a high Q can be obtained and Q _inb / (1 + cosθ ₁ ) &_lt; Q _V It becomes Therefore, the term "1 / Q" in the formula (4) can be ignored. Therefore, to satisfy the relation of Q _inb / (1 + cosθ ₁ ) = Q _inr / (1 + cosθ ₂ ) and θ ₁ , θ ₂ ≠ 2Nπ (N = 0, 1, ....), the parameter d ₁ , d ₂ , β ₁ , β ₂ , Δ ₁ , Δ ₂ , θ ₁ , θ ₂ , Q _inb , Q _inr , Q _V , so that the drop efficiency in the absence of the substance to be detected is about 1 (ie, 100 %), And since it differs greatly from the drop effect in the presence of a target substance, high sensitivity concentration measurement is possible.

In each of the above embodiments, a photonic crystal of a silicon semiconductor is used as the photonic sensor element, but the present invention is not necessarily limited thereto. For example, photonic crystals of various materials such as GaAs and InP may be applied. Can be.

The wavelength of the electromagnetic wave supplied from the electromagnetic wave source to the photonic sensor element may be appropriately set according to the substance to be detected. As the electromagnetic wave to be used, an optical communication wavelength band such as C band (1530 nm to 1565 nm) or L band (1565 nm to 1625 nm) is used. Can be suitably used depending on the target substance. As the electromagnetic wave generator 10, for example, a light emitting diode, a semiconductor laser, a halogen lamp, an ASE (Amplified Spontaneous Emission) light source, a SC (supercontinuum) light source, or the like can be used as a light source for generating electromagnetic waves in the optical communication wavelength band. . When generating electromagnetic waves of the near infrared wavelength band, a so-called linear heating element is placed between two points on one surface of a rectangular frame type support substrate formed by processing by micromachining technology using a silicon substrate. A light source of black body radiation, such as an infrared radiating element of a microbridge structure, can be used.

In the above-described embodiment, the configuration for detecting the concentration of the target substance set in advance has been disclosed. However, the present invention is not limited to this alone, and the change of the electromagnetic wave intensity output from the photonic sensor element is analyzed to determine the target. It can be applied to detect the specificity of the type of substance or the characteristic of the target substance.

In addition, in this embodiment, although the example used as a gas sensor, a humidity sensor, and a biosensor was disclosed, this invention is not limited only to this, It can use as a sensor which detects other substances, such as an ion sensor.

This application claims the priority of Japanese Patent Application No. 2004-87666 for which it applied on March 24, 2004, and merges all the content disclosed by the said Japanese application.

Claims (25)

In the sensor for detecting the properties of the target material, An electromagnetic wave generating source for supplying electromagnetic waves; A photonic sensor element having a photonic crystalline structure, comprising: a sensor waveguide for introducing the electromagnetic wave and a sensing resonator electromagnetically coupled to the sensor waveguide for resonating the electromagnetic wave to a specific wavelength, wherein A sensing resonator configured to change a characteristic of the electromagnetic wave emitted from the sensing resonator by being exposed to an atmosphere containing the target material; And A detector for receiving electromagnetic waves emitted from the sensing resonator, recognizing a change in intensity of the electromagnetic waves, and outputting a signal representing a characteristic of the target material. Sensor comprising a. The method of claim 1, The detector is characterized in that for determining the concentration of the target material based on the change in the characteristics of the electromagnetic wave and outputs a signal indicating the concentration of the target material. The method of claim 2, The photonic sensor element has a reference waveguide and a reference resonator in the photonic crystal structure, The reference waveguide introduces the electromagnetic wave from the electromagnetic wave generating source, The reference resonator is electromagnetically coupled to the reference waveguide to resonate the introduced electromagnetic wave to the specific wavelength, The reference resonator is concealed from the target material, The detector, An output intensity meter for providing a detection signal indicative of the intensity of the electromagnetic wave of said particular wavelength emitted from said sensing resonator; A reference intensity meter for providing a reference signal indicative of the intensity of the electromagnetic wave of the particular wavelength emitted from the reference resonator; And And a densitometer for comparing the detection signal with the reference signal to obtain an attenuation amount of the electromagnetic wave of the specific wavelength and to calculate the concentration of the target substance based on the attenuation amount. The method of claim 3, wherein The photonic sensor element has a photonic crystal structure arranged in a two-dimensional array, Each of the sensor waveguides and the reference waveguide extends within the two-dimensional photonic crystal structure to form input and output ports at both ends of the waveguide, respectively. Each said input port is arranged to receive electromagnetic waves from said electromagnetic wave generating source, Each said output port is coupled to each corresponding said output intensity meter and reference intensity meter to provide electromagnetic waves emitted from each corresponding said sense resonator and said reference resonator. The method of claim 3, wherein The photonic sensor element has a photonic crystal structure arranged in a two-dimensional array, Each of the sensor waveguide and the reference waveguide extends within the two-dimensional photonic crystal structure to form an input port and an output port at both ends of the waveguide, respectively. Each said sensing resonator and said reference resonator are disposed within said sensor waveguide and said reference waveguide, Each said input port is arranged to receive electromagnetic waves from said electromagnetic wave generating source, Each said output port is coupled to each corresponding said output intensity meter and reference intensity meter to provide electromagnetic waves emitted from each corresponding said sense resonator and said reference resonator. The method of claim 5, And the sensing resonator is arranged in plural along the sensor waveguide. The method of claim 3, wherein The photonic sensor element has a photonic crystal structure arranged in a two-dimensional array, Each of the sensor waveguides and the reference waveguide extends within the two-dimensional photonic crystal structure to form an input port at one end in its longitudinal direction, Each said input port is arranged to receive electromagnetic waves from said electromagnetic wave generating source, The photonic sensor element further includes a sensing output waveguide and a reference output waveguide, The sensing output waveguide and the reference output waveguide extend in parallel with the corresponding sensor waveguide and the reference waveguide, and are electromagnetically coupled to the sensing resonator and the reference resonator, respectively. Each of the sensed output waveguide and the reference output waveguide form an output port at one end in its longitudinal direction, the output port being coupled to respective corresponding output intensity meters and the reference intensity meters, respectively. The method of claim 3, wherein The photonic sensor element has a photonic crystal structure arranged in a two-dimensional array, The sensor waveguide and the reference waveguide respectively extend in the two-dimensional photonic crystal structure to form an input port at one end in the longitudinal direction thereof, Each said input port is arranged to receive electromagnetic waves from said electromagnetic wave generating source, Each of the output intensity meters and the reference intensity meters are disposed spaced apart from the plane of the photonic sensor element, and coupled to each of the corresponding sense resonators and the reference resonators and emitted from the sense resonators and the reference resonators. To receive the sensor. The method of claim 2, The photonic sensor element has a first photonic crystal structure and a second photonic crystal structure, wherein the first and second photonic crystal structures are different from each other, and are side-by-side in a two-dimensional array. relation), The sensor waveguide, An input waveguide extending over the first and second photonic crystal structures; A first output waveguide extending within the range of the first photonic crystal structure; And A second output waveguide extending within the range of the second photonic crystal structure Equipped with The sensing resonator is formed in the first photonic crystal structure, The second photonic crystal structure includes a reference resonator for resonating electromagnetic waves at a wavelength different from a specific wavelength inherent to the sensing resonator, The detector, An output intensity meter for providing a detection signal indicative of the intensity of the electromagnetic wave of said particular wavelength emitted from said sensing resonator; A reference intensity meter providing an intensity of electromagnetic waves emitted from the reference resonator; And A densitometer which compares the detection signal with the reference signal and calculates the concentration of the target material as a function of the attenuation amount by obtaining the attenuation amount of the electromagnetic wave of the specific wavelength in the sensing resonator Including as sensor. The method of claim 2, The electromagnetic wave source supplies electromagnetic waves including different wavelengths, so that the sensing resonator causes the electromagnetic waves to resonate at the specific wavelength determined by the target material. The detector selects an electromagnetic wave of the particular wavelength emitted from the sensing resonator and calculates a concentration of the target material based on the intensity of the selected electromagnetic wave. The method of claim 2, The electromagnetic wave generator sweeps the electromagnetic wave to change the wavelength with time, so that the sensing resonator resonates with the specific wavelength determined by the target material. And the detector extracts the intensity of the electromagnetic wave at the specific wavelength emitted from the sensing resonator and calculates the concentration of the target material based on the intensity of the electromagnetic wave. The method according to claim 10 or 11, wherein The sensor waveguide, in conjunction with the sensing resonator and the detector, forms one detection unit for detecting the specific type of target material, The sensor comprises a plurality of detection units, and the sensing resonator resonates the electromagnetic waves at different wavelengths to sense different kinds of target materials. The method according to claim 10 or 11, wherein A sensor is installed in the sensing resonator, and the sensing body reacts with the target material to change the resonant wavelength in the sensing resonator, thereby resonating the electromagnetic waves at the specific wavelength. The method according to claim 10 or 11, wherein The photonic sensor element has two sensing resonators, One sensing resonator of the two sensing resonators is provided with a sensing body that changes the wavelength of electromagnetic waves that react with the target material and resonate in the sensing resonator, And the two sensing resonators are electromagnetically coupled to each other to provide a synthesized electromagnetic wave output to the detector. The method according to claim 10 or 11, wherein A plurality of sensing resonators are arranged in a two-dimensional array, A plurality of detectors are arranged in a two-dimensional array, each of which is coupled to the sensing resonator to obtain the intensity of electromagnetic waves of the specific wavelength from each sensing resonator, The detector obtains the concentration for each sense resonator and provides a concentration distribution over the array of sense resonators. The method of claim 1, The electromagnetic wave source supplies electromagnetic waves of different wavelengths so that the sensing resonator causes the electromagnetic waves to resonate at the specific wavelength, A plurality of detectors are arranged in a two-dimensional array, each of which is coupled to the sensing resonator to obtain the intensity of the electromagnetic wave of the specific wavelength; The plurality of sensing resonators are configured to resonate electromagnetic waves of different specific wavelengths, respectively, The plurality of detectors provide a two-dimensional distribution of the different kinds of target materials by detecting the presence of different kinds of target materials based on the intensity of the electromagnetic waves emitted from the sensing resonators, respectively. Sensor. The method of claim 2, The sensing resonator resonates the electromagnetic wave of the specific wavelength, A sensitive body is installed in the sensor waveguide at a portion electromagnetically coupled to the sensing resonator, The sensitive material reacts with the target material to change the effective waveguide length between the sensor waveguide and the sensing resonator, thereby changing the intensity of the electromagnetic wave received at the target detector, The detector calculates a concentration of the target material based on a change in intensity of the electromagnetic wave. The method of claim 2, Two sensing resonators are formed in the photonic sensor element to be electromagnetically coupled to each other, and to resonate the electromagnetic waves of the specific wavelength, A sensitive body is installed in the energy coupling path between the two sensing resonators, and the sensitive body changes the intensity of the electromagnetic wave emitted from the sensing resonator by changing the effective waveguide length of the energy coupling path in response to the target material. And The detector calculates a concentration of the target material based on a change in intensity of an electromagnetic wave. The method of claim 1, The photonic sensor element has a first photonic crystal structure and a second photonic crystal structure, wherein the first and second photonic crystal structures are different from each other, and are arranged side by side in a two-dimensional array, The sensor waveguide is composed of an input waveguide and an output waveguide, wherein the input waveguide and the output waveguide extend in parallel with each other, each of which extends over the entire length of the first photonic crystal structure to form the second photonic crystal. Reach within the structure, The sensing resonator is disposed between the input waveguide and the output waveguide within the first photonic crystal structure, The input waveguide forms an input port for receiving electromagnetic waves from the electromagnetic wave generation source at one end in the longitudinal direction of the second photonic crystal structure, The output waveguide, at one end in its longitudinal direction away from the second crystal structure, forms an output port for emitting electromagnetic waves of the specific wavelength resonating in the sensing resonator, In the input waveguide, at the interface between the first photonic crystal structure and the second photonic crystal structure, an input reflector for reflecting the electromagnetic wave of the specific wavelength toward the output port side is formed, In the output waveguide, at the interface between the first photonic crystal structure and the second photonic crystal structure, an output reflector is formed which reflects the electromagnetic wave of the specific wavelength toward the input port side, In each of the input waveguide and the output waveguide, a sensitive body is formed at a portion connecting across the first photonic crystal structure and the second photonic crystal structure, and the sensitive body reacts with the target material to react with the input material. Varying the intensity of electromagnetic waves received at the detector by varying the reflection efficiency at the reflector and the output reflector, The detector calculates a concentration of the target material based on a change in intensity of the electromagnetic wave. The method of claim 1, Further comprising a controller for monitoring environmental parameters indicative of environmental conditions, The controller resonates the electromagnetic waves at the specific wavelength by correcting optical characteristics of the sensing resonator based on the environmental parameters. The method of claim 20, And a heater provided in the photonic sensor element, wherein the heater is operated by the controller to correct optical characteristics of the sensing resonator. The method of claim 1, And means for refreshing the target material or impurities replenished on the sensing resonator. The method of claim 22, And the refreshing means is a heater provided on the photonic sensor element side, and dissipates the target substance or impurities from the surface of the sensing resonator by heat. The method of claim 1, And modulating means for modulating one of a wavelength or an intensity of an electromagnetic wave supplied from said electromagnetic wave generating source to said sensor waveguide. A concentration detection method for detecting a concentration of a target material using a photonic sensor element having a sensor waveguide for introducing electromagnetic waves and a sensing resonator electromagnetically coupled to the sensor waveguide and resonating electromagnetic waves of a specific wavelength, the method comprising: Exposing the sensing resonator in an atmosphere containing the target material; Introducing an electromagnetic wave including the specific wavelength into the sensor waveguide; Detecting the intensity of electromagnetic waves resonating in the sense resonator; And Calculating the concentration of the target material by analyzing the intensity Concentration detection method comprising a.

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