JP6294150B2 - Light emitting / receiving device - Google Patents

Description

  The present invention relates to a light emitting / receiving device.

  Light-emitting elements are used in many applications. In addition to indoor / indoor lighting applications, optical devices that use light-emitting elements that emit light of a specific wavelength (sterilizers using ultraviolet light, reflected light) It is also used in the distance measuring device used. Furthermore, a light emitting / receiving device that combines a light emitting element and a light receiving element to detect a spatial state between the light emitting element and the light receiving element (an object detection device in a specific space, a gas sensor using infrared light (see Patent Document 1) Etc.). In order to examine this spatial state, it is necessary to efficiently guide the emitted light to the light receiving unit.

Special table 2001-503865 gazette

The light emitting element changes its light emission characteristics depending on the usage environment and changes over time. Specifically, a change in emission intensity and a change in emission wavelength can be mentioned. In the case of a light receiving / emitting device that detects the spatial state between the light emitting element and the light receiving element based on the output of the light receiving element described above, the spatial state is accurately detected from the output of the light receiving element when the light emission characteristics of the light emitting element change. You will not be able to.
As a method for reducing such a change in light emission characteristics, light emitted from the light emitting element is detected by a light receiving element for monitoring, and a change in the light emission characteristic of the light emitting element is detected based on the output of the light receiving element for monitoring. Examples of the method include monitoring and controlling the operation of the light emitting element and compensating the output of the light receiving element for detecting the state. However, since the light reaching the light receiving element for monitoring is similarly affected by attenuation or the like in the space, it cannot be accurately monitored if the state of the space changes.

As the wavelength of light is longer (for example, infrared rays of 3 μm or more), there is a problem of temperature characteristics of the light receiving element in addition to the deterioration of the light emitting element. Specifically, an optical sensor that detects long-wavelength light has low energy of long-wavelength photons, so that not only high sensitivity is difficult to realize, but also the sensitivity varies greatly depending on the sensor temperature. As an example of a long wavelength infrared sensor, a quantum infrared sensor having a photodiode structure using a semiconductor material such as InSb, InAlSb, or InAsSb as a light absorption layer can be given. Specific examples using these materials include a CO ₂ sensor that handles a wavelength band near 4.3 μm, a glue cause sensor in blood that uses a wavelength near 9.6 μm, and the like.
Accordingly, the present invention has been made in view of such circumstances, and provides a light receiving and emitting device that can compensate for signal fluctuations of light emission and light reception and can detect a spatial state with higher accuracy. The purpose is to do.

As a result of intensive studies to solve the above problems, the present inventor has come up with the following light receiving and emitting device.
A light emitting and receiving device according to an aspect of the present invention includes a first main surface and a second main surface facing the first main surface, and a light emitting element and a first light emitting element formed on the first main surface, respectively. A second substrate having a first substrate having a sensor portion, a first main surface and a second main surface facing the first main surface, and having a second sensor portion formed on the first main surface And at least a part of the light emitted from the light emitting element and emitted from the second main surface of the first substrate, which is disposed at a position away from each of the first substrate and the second substrate. And a sealing portion that covers and seals the first main surface of the first substrate and the first main surface of the second substrate, and the light reflecting portion includes the light reflecting portion. a concave mirror for reflecting and condensing at least a portion, the first substrate and the second substrate are adjacent to each other with the side surface are opposed to each other placement It is characterized in that is.

  According to one embodiment of the present invention, it is possible to provide a light emitting and receiving device that compensates for signal fluctuations of light emission and light reception and can detect a spatial state with higher accuracy.

It is a figure which shows the structural example of the light emitting / receiving apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the cross section of a 1st board | substrate and a 2nd board | substrate. It is a figure which shows the structural example of the light emitting / receiving apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the structural example of the light emitting / receiving apparatus which concerns on 3rd Embodiment of this invention. It is a figure which shows the structural example of the light emitting / receiving apparatus which concerns on 4th Embodiment of this invention. It is a figure which shows the structural example of the light emitting / receiving apparatus which concerns on 5th Embodiment of this invention. 4 is a diagram illustrating an example of a terminal 47 connected to a signal processing unit 45. FIG.

<Overall configuration>
Hereinafter, modes for carrying out the present invention (hereinafter, this embodiment) will be described. The light emitting / receiving device according to the present embodiment is a light emitting / receiving device that includes a light emitting element and a first sensor unit and a second sensor unit that are arranged so that light output from the light emitting element is incident thereon. This light emitting and receiving device has a first main surface (for example, a front surface) and a second main surface (for example, a back surface) opposite to the first main surface, and the light emitting element and the first sensor on the first main surface. A first substrate provided with a portion. The light emitting and receiving device has a first main surface (for example, a front surface) and a second main surface (for example, a back surface) opposite to the first main surface, and the second sensor unit on the first main surface. Is provided.

  The arrangement position of the first sensor unit is set to a position where the light reflected by the second main surface of the first substrate out of the light output from the light emitting element is incident on the first main surface of the first substrate. ing. Thereby, the light radiated | emitted from the light emitting element always passes the environment (optical path) of the same state, and injects into a 1st sensor part. Therefore, even when the light emission characteristics of the light emitting element change due to a change in usage environment or aging, or even if the sensitivity of the light receiving element changes due to temperature, the space by the second sensor unit (the light receiving element for state detection). It becomes possible to accurately detect the state.

  In the light emitting / receiving device according to the embodiment of the present invention, it is preferable that the first sensor unit and the second sensor unit have the same temperature characteristics. In the present embodiment, the “same temperature characteristic” means a state in which the temperature characteristic is substantially uniform to the extent that the effect of the present invention is not hindered. Specifically, under the condition where the gas to be detected does not exist, the output signal of the first sensor unit is output when the sensor temperature is Tx in the general operating temperature range of the light emitting and receiving device (for example, in the range of 0 ° C. to 50 ° C.). Consider a case where the output signal of S1 and the second sensor unit is S2. In this case, when the temperature changes by 1 ° C., that is, when the sensor temperature reaches Tx ± 1 ° C., the output signal of the first sensor unit is a × S1, and the output signal of the second sensor unit is b × S2. And a / b is preferably 0.8 or more and 1.2 or less per 1 ° C., more preferably 0.9 or more and 1.1 or less, and 0.99 or more and 1.01 or less. More preferably it is.

  If the ratio of the maximum value and the minimum value of the change coefficient ratio (a / b [/ ° C.]) of the output of the first sensor unit and the second sensor unit per 1 ° C. is 0.8 to 1.2 Regardless of the ambient temperature of the light receiving and emitting device, it is preferable because the second sensor unit can accurately detect the spatial state even when the light emission characteristics of the light emitting element change. Specifically, the output change coefficients (a and b) of the first sensor unit and the second sensor unit when the temperature of the first sensor unit and the second sensor unit is changed from 0 ° C. to 50 ° C. are obtained. By calculating the ratio a / b / ΔT when ΔT is changed by ΔT, the ratio of the change coefficient of output per 1 ° C. can be confirmed.

In the present invention, it is necessary to suppress as much as possible the temperature difference between the temperature of the first sensor unit provided on the first substrate and the second sensor unit provided on the second substrate. When not only the environmental temperature but also the temperature of the fluid or gas flowing in the space itself changes, these changes cause the temperature difference between the first substrate and the second substrate (that is, the temperature difference between the first sensor unit and the second sensor unit). ) Can be a factor that instantaneously fluctuates.
The present invention is arranged so that the first substrate and the second substrate are close to each other, and can suppress the influence of a disturbance due to a fluid / gas temperature change or a sudden temperature change of the environmental temperature. In the present invention, the separation distance L between the first substrate and the second substrate is preferably smaller than the length of the longest side of the sides of the first substrate and the second substrate. Specifically, the shape of the substrate in plan view is a rectangle, and the length of each side of the rectangle is a and b (a ≧ b), and the length of the gap between the first substrate and the second substrate (that is, When the separation distance is L, it is sufficient that L ≦ b, L ≦ 0.8b is better, and L ≦ 0.5b is more desirable.

Further, from the viewpoint of the S / N ratio of light emission / light reception, if the distance between the center of gravity of the light emitting surface of the light emitting element and the center of gravity of the light receiving surface of the second sensor unit is within 3 mm, the S / N of light emission / light reception is The ratio becomes high, and highly accurate spatial state measurement becomes possible. In addition, when the S / N ratio for light emission / light reception is increased, the current consumption of the light emitting element can be reduced, and the power consumption of the light emitting / receiving device can be further reduced.
As a method of setting the maximum value and the minimum value of the change coefficient ratio of the output per 1 ° C. of the first sensor unit and the second sensor unit in the above range, the first sensor unit and the second sensor unit are made of the same material and are the same. The method of making it the laminated structure of these is mentioned. By using the same material and the same laminated structure, the temperature characteristics of the first sensor unit and the second sensor unit are theoretically the same.

Further, in order to make the temperature characteristics of the first sensor unit and the second sensor unit the same, the stacked structure is the same, and the first sensor unit and the second sensor unit are manufactured at the same time. It is preferable to form the second sensor portion at the same time.
Moreover, in order to implement | achieve the high S / N ratio of the whole light emitting / receiving apparatus, you may change the area of a 1st sensor part and a 2nd sensor part. For example, when the light reaching the first sensor unit is strong, the S / N ratio of the entire light receiving and emitting device does not decrease even if the light receiving area of the first sensor unit is reduced to such an extent that the S / N does not decrease. For this reason, the light receiving area of the first sensor unit can be reduced, and the area occupied by the light emitting element can be increased accordingly, and the S / N ratio of the entire light receiving and emitting device can be improved.

  Further, the first sensor unit and the second sensor unit may be formed of a large number of light receiving units. In this case, the light receiving area is proportional to the number of light receiving portions, and the larger the light receiving area, the higher the S / N ratio. Further, even if the respective light receiving areas of the first sensor unit and the second sensor unit are changed, the spectral sensitivity characteristic and the temperature characteristic do not change, so the effect of the present invention is maintained. When the number of light receiving parts of the first sensor part is n and the number of light receiving parts of the second sensor part is m, the ratio of the number of light receiving parts may be about 1/500 n / m. 1/100 or 1/10 may be used. It is preferable to design the ratio of the number of light receiving parts according to the light emitting ability of the light emitting element.

  In addition, the first sensor unit and the second sensor unit may be formed on the same substrate using the same material and the same process. Accordingly, the spectral sensitivity characteristics of the first sensor unit and the second sensor unit become the same, and the temperature characteristics of the first sensor unit and the second sensor unit become the same, so that the effect of the present invention is most exhibited. Here, the spectral sensitivity characteristic means sensitivity at each wavelength. As will be described later, an optical filter (for example, a bandpass filter) that selects the wavelength of light is provided on the second main surface of the first substrate, thereby entering the first sensor unit and the second sensor unit. It becomes possible to select a wavelength band. Such an optical filter needs to be provided in the middle of the optical path, but is preferably provided on the second main surface of the first substrate and / or the second substrate. Since the optical filter can realize a transmission characteristic (several tens of nm to several hundreds of nm) with a narrow half-value width, a specific wavelength can be easily selected.

Furthermore, in the present invention, the same light filter passes through the same optical filter twice, so that the filter characteristic becomes steeper, and the spatial state detection with higher accuracy can be measured.
From the viewpoint of utilization efficiency of the substrate area, the first sensor unit and the second sensor unit have a large number of light receiving units having the same structure, and the number of the light receiving units is different between the first sensor unit and the second sensor unit. It is preferable. The number of light receiving parts is not particularly limited, but in general, a light receiving part installed on the same substrate as the light emitting element absorbs more light flux per unit area than a light receiving part installed on a different substrate. Can do. For this reason, the light receiving area of the first substrate may be smaller than the light receiving area of the second substrate.

Moreover, in order to keep the balance of the S / N ratio of the signals of both the first sensor unit and the second sensor unit without waste, it is preferable that the light receiving areas (number of light receiving units) are different. When the light emitting / receiving device according to the present embodiment is applied to a gas sensor, the concentration is calculated based on the output signals (Ip1, Ip2) of the first sensor unit and the second sensor unit. It is determined by the S / N ratio between the sensor unit and the second sensor unit.
The output signal ratio (Ip1 / Ip2) is determined by each material of the first substrate and the second substrate, each processing method of the second main surface of the first substrate and the second main surface of the second substrate, the presence or absence of the control layer, and its optical It varies depending on characteristics. As will be described later, if these output signal ratios are set to an appropriate ratio, the light receiving / emitting device having the desired accuracy while improving the utilization efficiency of the substrate and minimizing the area of the sensor unit while minimizing the area. Can be designed.

Next, each component of the light emitting / receiving device will be described more specifically.
[First substrate]
In the light receiving and emitting device according to the present embodiment, the first substrate has a light emitting element and a first sensor unit on the first main surface. The material for the first substrate is not particularly limited. Examples of the material of the first substrate include Si, GaAs, sapphire, InP, InAs, and Ge. However, the material is not limited to this, and may be selected according to the wavelength band to be used. A semi-insulating substrate is preferably used as the first substrate from the viewpoint that the first sensor unit and the light emitting element can be easily electrically insulated. A GaAs substrate is particularly preferable from the viewpoint that a semi-insulating substrate can be produced and that the diameter can be increased. From the viewpoint of improving measurement sensitivity, the material of the first substrate is preferably a material having high transparency for light output from the light emitting element. In addition, from the viewpoint of highly accurately compensating for output fluctuations of the light emitting element, the material of the first substrate is preferably a material that efficiently reflects light output from the light emitting element on the second main surface. Furthermore, the first substrate is preferably a GaAs substrate from the viewpoint of easily forming the first sensor portion, the second sensor portion, and the light emitting element having a laminated structure containing indium (In) or antimony (Sb) as described later. .

The material used for the first sensor unit, the second sensor unit, and the light receiving element is preferably a III-V group compound semiconductor, and is selected from the group consisting of indium (In), aluminum (Al), and gallium (Ga). More preferably a compound semiconductor of at least one group III atom and at least one group V atom selected from the group consisting of antimony (Sb) and arsenic (As). InSb or AlInSb, GaInSb, AsInSb More preferably, it is a compound semiconductor containing at least. When the gas to be detected is CO ₂ , AlInSb or GaInSb is preferably used for the first sensor unit, the second sensor unit, and the light receiving element in order to detect absorption of CO ₂ near a wavelength of 4.3 μm. In addition, when detecting a gas such as evaporated alcohol, it is necessary to further increase the wavelength (9 to 10 μm). In this case, AsInSb may be used for the first sensor unit, the second sensor unit, and the light receiving element. .

  In addition, the first substrate has a light amount and a reflection / reflection amount of light output from the light emitting element on the second main surface of the first substrate from the viewpoint of light extraction efficiency and light reflection / scattering efficiency. It is preferable to have a control layer for controlling the scattering angle, the amount of light emitted from the second main surface of the first substrate into the cell, and the radiation angle. Since the refractive index of a generally used substrate material is high, it is difficult to extract light from the substrate to the outside, and much of the light output from the light emitting element is scattered in the substrate. In the light emitting / receiving device according to the present embodiment, the control layer is provided on the second main surface of the first substrate so that the S / N ratio of the entire sensor is increased (high resolution can be obtained). Is possible. Specific examples of the control layer include an antireflection film, a laminated film of a large number of materials having different refractive indexes, a roughened layer, or a combination thereof.

[Light emitting element]
In the light emitting / receiving device according to the present embodiment, the light emitting element is formed on the first main surface of the first substrate. The light emitting element is not particularly limited as long as it outputs light including a wavelength absorbed by the gas to be detected. A specific form of the light emitting element is not particularly limited as long as it can be formed on the first main surface of the first substrate. Specific examples of light-emitting elements include MEMS (Micro Electro Mechanical Systems) and LEDs (Light Emitting Diodes). Among them, from the viewpoint of reducing noise due to light absorption of components other than the gas to be detected. It is preferable to output only light in a wavelength band where gas absorption is large. Specifically, the LED structure may be desirable because the emission wavelength band is controlled by the band gap of the active layer.

The light-emitting element preferably has a stacked structure portion of a PN junction or a PIN junction formed by using a deposition method such as MBE (Molecular Beam Epitaxy) or CVD (Chemical Vapor Deposition). By supplying electric power to the laminated structure portion, it can operate as an LED and emit light having a wavelength corresponding to the band gap of the material of the laminated structure portion. By including In or Sb in the stacked structure portion (that is, the active layer), light in the infrared region (that is, infrared light) can be emitted. Specifically, by using InSb, InAlSb, or InAsSb for the active layer, a wavelength of 1 to 12 μm can be output.
A narrow band gap material in which the active layer contains In and / or Sb generally has a large temperature characteristic (change in the light emission characteristic due to the temperature of the light emitting element itself). However, according to the light emitting and receiving device of the present embodiment, even if there is a large change in light emission characteristics, it is possible to always monitor the change accurately and control the operation of the light emitting element based on the monitoring result. Thus, it is possible to always achieve a constant light emission characteristic.

[First sensor unit]
In the light emitting / receiving device according to the present embodiment, the first sensor unit is formed on the first main surface of the first substrate. The arrangement position of the first sensor part is not particularly limited as long as the light reflected from the second main surface opposite to the first main surface of the first substrate is incident on the light output from the light emitting element. From the viewpoint of signal processing response speed, the laminated structure of the first sensor unit is a diode structure of a PN junction or a PIN junction, and may include any material of indium or antimony. Furthermore, a mixed crystal material further including at least one material selected from the group consisting of Ga, Al, and As may be included. Further, from the viewpoint of uniform temperature characteristics, the light receiving element material and the laminated structure of the first sensor section are preferably the same as the light emitting element material and the laminated structure.

From the viewpoint of the S / N ratio when the sensor unit is connected to a circuit (amplifier), it is preferable to provide a large number of light receiving elements in series. Thereby, since the internal resistance of the whole light-receiving part can be enlarged, when connected to an amplifier, a high S / N ratio can be realized. Therefore, it is preferable that the first sensor unit of the present embodiment has a configuration in which a plurality of light receiving elements are connected in series.
In addition, since the light emitting element and the first sensor unit are disposed on the same first substrate, the amount of light incident on the first sensor unit tends to be larger than the amount of light incident on the second sensor unit. For this reason, the total area of the light receiving part of the first sensor part can be made smaller than the total area of the light receiving part of the second sensor part. Thereby, further miniaturization of the light emitting / receiving device can be achieved.

[Second board]
In the light emitting / receiving device according to the present embodiment, the second substrate is not particularly limited as long as it has the second sensor part on the first main surface. Light incident from the second main surface side passes through the inside of the second substrate and is incident on the second sensor unit. The material for the second substrate is not particularly limited. Examples of the material for the second substrate include, but are not limited to, a Si substrate, a GaAs substrate, and sapphire. From the viewpoint of improving measurement sensitivity, the material of the second substrate is preferably a material having high transparency to light incident from the second main surface side.

  From the viewpoint of miniaturization, it is preferable that the second substrate is disposed adjacent to the first substrate with the side surfaces facing each other, and the light blocking portion is disposed between the first substrate and the second substrate. The light emitting / receiving device of this embodiment preferably includes a light reflecting section described later. Moreover, it is preferable that said light shielding part is arrange | positioned at the junction part of a 1st board | substrate and a 2nd board | substrate. By having the light blocking unit arranged in this way, it is possible to prevent light output from the light emitting element from entering the second sensor unit without passing through the external space, and detection sensitivity in the second sensor unit. Can be improved. In the present embodiment, a part of the sealing portion may be interposed between the first substrate and the second substrate. A portion interposed between the first substrate and the second substrate in the sealing portion functions as a light blocking portion.

[Second sensor unit]
In the light emitting / receiving device according to the present embodiment, the second sensor unit is not particularly limited as long as it is disposed on the second substrate. As described above, from the viewpoint of equalizing the temperature characteristics of the second sensor unit and the first sensor unit, the second sensor unit and the first sensor unit are formed on the same substrate in the manufacturing process. It is preferable to have the same laminated structure.
From the viewpoint of the response speed of signal processing, the laminated structure of the second sensor part is a PN junction or PIN junction diode structure, and preferably contains any material of indium or antimony.
From the viewpoint of improving measurement sensitivity, an optical that transmits only a specific wavelength band (a preset wavelength band) in an optical path until light emitted from the second main surface of the first substrate enters the second sensor unit. It is preferable to have a filter. In the light receiving and emitting device according to the present embodiment, when the light output from the light emitting element is light in a wide wavelength band, it is particularly preferable to have the optical filter.

  In the light emitting and receiving device according to the present embodiment, the first substrate having the first sensor unit and the second substrate having the second sensor unit are originally the same wafer (that is, the same before dicing), and the first sensor It is preferable that the part and the second sensor part have the same laminated structure. Thereby, the variation of the sensitivity characteristic between the 1st sensor part and the 2nd sensor part and the temperature characteristic of a sensitivity is suppressed, and the effect of the present invention can be exhibited more. Specifically, when the sensitivity of the first sensor unit is Ri2 (λ) [A / W] and the sensitivity of the second sensor unit is Ri2 (λ) [A / W], | Ri2 (λ) −Ri1 ( [lambda]) | / (Ri1 ([lambda])) should be 20% or less, more preferably 10% or less, and even more preferably 5% or less, but within 2%, more preferably 1% or less. The effects of the invention can be further exerted, and temperature / aging change compensation can be performed with extremely high accuracy.

So far, the case where the light emitting element (first light emitting element) and the first sensor unit are provided on the first substrate and only the second sensor unit is provided on the second substrate has been described. However, the present invention is not limited to this. In the present invention, in addition to the above configuration, a light emitting element (second light emitting element) may be provided on the second substrate. In this case, at time T1, a part of the light emitted from the first light emitting element is reflected by the second main surface of the first substrate, enters the first sensor unit, and is emitted from the second main surface of the first substrate. Is reflected by the mirror surface of a light reflecting portion (for example, a concave mirror) and enters the second sensor portion on the second substrate. At time T2, as in time T1, a part of the light emitted from the second light emitting element is reflected by the second main surface of the second substrate and enters the second sensor unit, and the second main light of the second substrate is reached. The light emitted from the surface is reflected by the mirror surface of the light reflecting portion and enters the first sensor portion on the first substrate.
In such a setting, it is desirable that the light has the same S / N ratio in both directions when receiving and emitting light. In order to perform temperature correction, it is desirable to equalize the sensitivity and temperature characteristics of the first sensor unit and the second sensor unit, and it is necessary to take a ratio of a signal corresponding to the transmittance in the spatial state and a signal through the substrate. . Thereby, the temperature characteristics of the light emitting element and the change with time can be compensated. The signal ratio obtained at time T1 is R1 = S2 / S1, the signal ratio obtained at time T2 is R2 = S1 / S2, and the average value of the signal ratio R = (R1 + R2) / 2 is used as the information on the transmittance in the spatial state. Since this can be used to detect the S / N ratio, this configuration may be preferable.

[Light reflection part]
A concave mirror can be used as the light reflecting portion. The role of the concave mirror is to reflect the light emitted from the substrate out of the light output from the light emitting element and cause the second sensor unit to detect it. By using the concave mirror, the S / N ratio of the light emitting / receiving device can be dramatically improved. As a structure of the concave mirror, any structure that can be fixed on the sealing portion may be used. The material used for the concave mirror may be metal, resin, ceramic, or a combination thereof, and there is no limitation on the material or combination as long as the inner wall can efficiently reflect light from the light emitting element. When a resin is used, a resin having a heat resistance of a high temperature (for example, 150 ° C.) or higher is desirable during solder reflow of the light emitting / receiving element. Examples of the resin used for the resin mold part of a general semiconductor element include epoxy resin and polyphthalamide. Although not shown, an opening may be provided between the concave mirror, the resin mold part, or between the concave mirror and the resin mold part so that the substance to be detected (liquid or gas) enters the optical path. As will be described later, the number of concave mirrors may be increased by the number of light emitting elements.
Note that when the amount of light emitted from the optical element is Pout, the concave mirror is preferably arranged so that the amount of light incident on the second sensor unit is 0.3 × Pout or more.

[Signal processing section]
The signal processing unit supplies a current to the light emitting element, receives an output signal from each sensor unit, and outputs a signal corresponding to a spatial state (for example, transmittance, concentration, etc.).
[Optical filter]
The optical filter has a role of transmitting only a part of the wavelength of light. A specific configuration of the optical filter is generally a film in which films having different refractive indexes are alternately laminated on a transparent substrate (for example, Si in the case of long-wavelength infrared). For example, in the case of a substance such as CO ₂ gas, a band pass filter that transmits only a wavelength in the vicinity of a wavelength of 4.3 μm may be used. In order to fix the filter, a filter holding part may be further provided.
Further, as will be described later, since light passes through the same filter twice, sharp bandpass characteristics can be obtained even if the number of films stacked on the optical filter is reduced. Accordingly, even a simple optical filter can realize a bandpass filter half-value width of a high-accuracy filter class, which is preferable in some cases.

[(Detected substance) supply port]
The supply port of the detected substance is, for example, an opening for allowing the detected substance to enter and exit the optical path in the cell surrounded by the light reflecting portion and the sealing portion. There is no limitation on the diameter and location of the opening of the supply port provided in the cell, but the smaller the cross-sectional area, the longer the supply speed of the substance to be detected and the response speed of the state detection function. On the other hand, when the opening is provided in the concave mirror, the larger the cross-sectional area, the narrower the light reflecting surface, so that the efficiency of light reception / emission (light emission / light reception) decreases. At this time, it is necessary to sufficiently consider the S / N ratio together with the response speed.

<Effect of embodiment>
This embodiment has the following effects (1) to (3).
(1) The optical path from the light emitting element to the first sensor unit is in the first substrate, and no optical filter (for example, a bandpass filter) or external space exists in the optical path. Thereby, compared with the case where a band pass filter and external space exist in an optical path, attenuation of the light in an optical path can be suppressed irrespective of the use environment of a light receiving / emitting device, and the signal which a 1st sensor part detects The decrease in the S / N ratio can be suppressed.
(2) As described above, it is possible to suppress a decrease in the S / N ratio of the signal detected by the first sensor unit. Further, it is possible to compensate for a measurement error due to a change in the emission intensity without periodically calibrating the change in the emission intensity of the light emitting element. Accordingly, measurement variations of the light emitting / receiving device can be reduced, so that a highly accurate and reliable light emitting / receiving device can be provided.
(3) The temperature difference due to the disturbance between the first sensor unit and the second sensor unit can be suppressed. That is, the present embodiment compensates for signal fluctuations of light emission and light reception caused by changes with time and changes in usage environment (for example, environmental temperature), and even when the light emission characteristics of the light emitting element change or depending on the temperature, Even if each sensitivity of the sensor unit or the second sensor unit changes, it is possible to provide a light emitting and receiving device that can detect the spatial state by the second sensor unit with higher accuracy. Furthermore, it is possible to realize a long optical path from the light emitting element to the second sensor part while reducing the temperature difference between the first and second sensor parts due to disturbance to the maximum, so that the change in the concentration of the substance to be detected can be detected with high sensitivity. It can be detected.
As described above, according to the present embodiment, it is possible to reduce the temperature difference between the first sensor unit for compensation and the second sensor unit for detecting the spatial state to the limit while realizing a long optical path.・ It is possible to precisely compensate for fluctuations in the received light signal and to detect the spatial state with higher accuracy.

<Application of Embodiment>
As described above, the light emitting and receiving device according to the present embodiment can be applied to various devices, and the state of the optical path space between the light emitting element and the second sensor unit (the presence or absence of a specific gas, the concentration, the fluid The presence / absence and concentration of the specific component) can be detected. For example, a gas sensor for detecting the concentration of a specific gas in a building or measuring instrument, a gas sensor mounted on a portable communication device such as a mobile phone or a smartphone, or a gas concentration in a moving means such as an automobile, a train, or an aircraft. It can be used for a gas sensor for detection, a component detection device for a substance (for example, water or body fluid) flowing in the optical path space between the light emitting element and the second sensor unit, measurement of glucose concentration in blood, and the like.
For example, the CO ₂ concentration is considered to be correlated with living organisms' sleep. When the measurement target gas of the light emitting / receiving device according to the present embodiment is CO ₂ , the CO ₂ concentration can be detected with high accuracy even in an environment where the ambient temperature is likely to change greatly. Thereby, the light emitting / receiving device according to the present embodiment is suitable, for example, as a dozing prevention device in driving a car (for example, when a predetermined CO ₂ concentration is reached, an alarm is issued / automatic ventilation is performed).

Further, glucose detection in blood can be measured grayed Turkey over scan concentration in blood glucose than measuring the absorption at a wavelength of wavelength 9.6 .mu.m. By using the light emitting / receiving device according to the present embodiment, a small, high-accuracy and high-reliability measuring meter can be realized even in the wavelength band of 9.6 μm. By realizing such a glucose concentration measurement meter, a diabetic patient can examine blood glucose level accurately without damaging the skin as caused by an invasive method by himself, and more accurately dosing ( For example, management of insulin) can be realized.
The light emitting / receiving device according to the present embodiment has a higher S / N ratio than the conventional light emitting / receiving device. Application to a small device (for example, a portable communication device) that has been difficult becomes possible.

<Specific Example of Embodiment>
Next, specific examples (first to fifth embodiments) of the embodiment of the invention will be described with reference to the drawings. Note that, in each drawing described below, parts having the same configuration are denoted by the same reference numerals, and repeated description thereof is omitted.
[First Embodiment]
FIG. 1 is a conceptual diagram showing a configuration example of a light receiving and emitting device according to the first embodiment of the present invention. FIG. 1 (a) is a plan view, and FIG. 1 (b) is a plan view taken along line X1-X'1. It is sectional drawing cut | disconnected by. As shown in FIGS. 1 (a) and 1 (b), in this light emitting / receiving device, the first substrate 41 and the second substrate 42 are spaced apart from each other with their side surfaces (that is, part of the outer peripheral side surface) facing each other. Are arranged next to each other.
The first main surface 411 and its side surface of the first substrate 41 and the first main surface 421 and its side surface of the second substrate 42 are covered and sealed by the resin mold part 50. A part of the resin mold part 50 is interposed in the gap between the first substrate 41 and the second substrate 42. Thereby, light is shielded between the side surface of the first substrate 41 and the side surface of the second substrate 42. Further, the second main surface 412 of the first substrate 41 and the second main surface 422 of the second substrate 42 are exposed from the resin mold part 50, respectively. In this example, the second main surface 412 of the first substrate 41 and the second main surface 422 of the second substrate 42 are flush with the surface (for example, the upper surface) of the resin mold portion 50.

As shown in FIG. 1A, the light receiving and emitting device further includes a signal processing unit 45 sealed in the resin mold unit 50 and a terminal connected to the signal processing unit 45. The signal processing unit 45 supplies current to the light emitting elements formed on the first main surface 411 of the first substrate 41, and also includes a first sensor unit formed on the first main surface 411 of the first substrate 41 and It has a function of processing each output signal from the second sensor unit formed on the first main surface 421 of the second substrate 42.
FIG. 7 shows an example of a terminal 47 connected to the signal processing unit 45. As shown in FIG. 7, the element on the first substrate 41, the element on the second substrate 42, and the signal processing unit 45 are connected by wire bonding (for example, a wire 49 as shown in FIG. 7). Also good. Further, the signal processing unit 45 and the terminal 47 may also be connected by wire bonding. At least an active surface (surface on which a circuit is formed) of the signal processing unit 45 is covered and sealed by the resin mold unit 50. Further, at least a part of the terminal 47 connected to the signal processing unit 45 is exposed from the resin mold unit 50. As a result, the terminal 47 is used as a terminal for internal / external electrical connection of the light emitting / receiving device.

Further, as shown in FIGS. 1A and 1B, the light emitting and receiving device is located at a position away from the first substrate 41 and the second substrate 42, and the second main surface 412 of the first substrate 41. The concave mirror 60 is provided on the side and the second main surface 422 side of the second substrate 42. Concave concave mirror 60 (i.e., a concave curved surface) is 601 a mirror for reflecting light, the second main surface and the second of which is directed toward et al is the side of the main surface of the second substrate 42 of the first substrate 41. Thereby, the concave mirror 60 can reflect the light emitted from the second main surface 412 of the first substrate 41 toward the second sensor unit 32. In this light receiving and emitting device, the concave mirror 60 and the resin mold part 50 constitute a cell 10. The cell 10 is provided with a supply port (not shown) for introducing a substance to be detected (for example, a measurement target gas). The measurement target gas is introduced into the space in the cell 10 through the supply port.

FIG. 2 is a cross-sectional view illustrating a configuration example of the first substrate 41 and the second substrate 42. In FIG. 2, the first substrate 41 and the second substrate 42 have different dimensions, but may have the same dimensions. Further, as will be described later, a light emitting element (second light emitting element) may also be provided on the second substrate 42.
As illustrated in FIG. 2, the light emitting element 20 includes, for example, a first conductive type semiconductor layer 201 formed on the first main surface 411 of the first substrate 41 and a second conductive type formed on the semiconductor layer 201. A semiconductor layer 202 and an electrode 203 of the mold, and an electrode 204 formed on the semiconductor layer 202.
The first sensor unit 31 includes, for example, a first conductivity type semiconductor layer 311 formed on the first main surface 411 of the first substrate 41 and a second conductivity type semiconductor layer 312 formed on the semiconductor layer 311. And an electrode 313 and an electrode 314 formed over the semiconductor layer 312. For example, the second sensor unit 32 includes a first conductivity type semiconductor layer 321 formed on the first main surface 421 of the second substrate 42 and a second conductivity type semiconductor layer 322 formed on the semiconductor layer 321. And an electrode 323 and an electrode 324 formed over the semiconductor layer 322. The first conductivity type semiconductor layers 201, 311, and 321 are, for example, N-type semiconductor layers. The second conductivity type semiconductor layers 202, 312, and 322 are, for example, P-type semiconductor layers.

In FIG. 2, the first sensor unit 31 and the second sensor unit 32 are shown as one element. However, from the viewpoint of the S / N ratio, a plurality of elements are electrically connected to form one sensor unit. Also good. Further, from the viewpoint of light emission efficiency, the light emitting element 20 may also be a large number of elements that are electrically connected. Further, a genuine semiconductor layer (so-called i-type semiconductor layer) is inserted between each of the first conductivity type semiconductor layers 201, 311, 321 and the second conductivity type semiconductor layers 202, 312, 322, and a PIN junction is formed. It may be formed.
Further, the first substrate 41 in FIG. 2 gaps have been found interposed between the second substrate 42, light blocking resin mold portion 50 (see FIG. 1) is interposed in this gap. Thereby, the light emitted from the light emitting element does not reach the second sensor unit via the substrate. In the case of a light emitting / receiving device combined with temperature correction, temperature correction can be performed with higher accuracy.

According to the light emitting / receiving device according to the first embodiment, the second substrate 42 and the first substrate 41 are arranged in parallel, whereby the light receiving / emitting device can be further reduced in size. Further, by arranging the first substrate 41 and the second substrate 42 at positions close to each other, the light emitted from the light emitting element 20 can be collected and detected more efficiently. Further, by bringing the first substrate 41 and the second substrate 42 closer, the substrate temperature difference, that is, the temperature difference between the first sensor unit 31 and the second sensor unit 32 can be reduced. That is, even if non-uniform stagnation of gas or liquid generated around the light emitting / receiving device occurs, the temperature difference between the first sensor unit 31 and the second sensor unit 32 can be reduced, and highly accurate measurement can be realized.
Specifically, the distance between the center of gravity of the light emitting surface of the light emitting element 20 and the center of gravity of the light receiving surface of the first sensor unit 31 is 10 mm or less, more preferably 5 mm or less, and most preferably 3 mm or less. In addition, since the light receiving and emitting device includes the concave mirror 60 as a light reflecting portion, the infrared light (dotted line) emitted from the second main surface 412 of the first substrate 41 out of the light output from the light emitting element 20 is the concave mirror 60. The light can be reflected and selectively incident on the second sensor unit 32, so that a more sensitive light emitting / receiving device can be realized.

[Second Embodiment]
FIG. 3 is a conceptual diagram showing a configuration example of a light receiving and emitting device according to the second embodiment of the present invention.
The light emitting / receiving device according to the second embodiment includes an optical filter 70. The outer periphery of the optical filter 70 is held by a filter holding member 71, and is arranged to face the second main surface 412 of the first substrate 41 and the second main surface 422 of the second substrate 42. As shown in FIG. 3, the concave surface (that is, the mirror surface) 601 of the concave mirror 60 has a hemispherical shape, but any curved surface may be used as long as light can be collected efficiently. By providing the optical filter 70, only the characteristic wavelength can be selected.
In the light receiving and emitting device according to the second embodiment, light is transmitted twice through the same optical filter 70 (that is, light that is emitted from the second main surface 412 of the first substrate 41 and travels toward the concave mirror 60 is optical filter 70). Light, which is reflected by the concave mirror 60 and directed to the second main surface 422 of the second substrate 42 is transmitted through the optical filter 70), so that light emission / light reception characteristics with a very narrow half-value width in the emission spectrum can be realized. . In this way, the wavelength resolution can be maximized. For example, in the application of a gas sensor, accurate concentration measurement of a mixed gas is possible.
In the second embodiment, the substrate of the optical filter 70 is provided separately from the first and second substrates, but at least one of the second main surface of the first substrate 41 and the second main surface of the second substrate 42 is provided. Two or more types of refractive index films may be provided directly. In this case, from the viewpoint of assembly, the number of parts is reduced, and the assembly process is simplified.

[Third Embodiment]
FIG. 4 is a conceptual diagram showing a configuration example of a light receiving and emitting device according to the third embodiment of the present invention.
In the second embodiment described above, the case where the optical filter 70 is disposed to face the second main surface of the first substrate 41 and the second main surface of the second substrate 42 has been described. Although FIG. 3 of 2nd Embodiment showed the case where the concave surface (namely, mirror surface) 601 of the concave mirror 60 was hemispherical shape, the concave surface of the concave mirror 60 is not limited only to a curved surface.
As shown in FIG. 4, the mirror surface 601 may have a curved central portion and a flat outer peripheral portion. In this case, the filter size of the optical filter 70 may be designed so that light is reflected only on a part of the concave mirror 60 (for example, the central part). In this case, a part of the light from the light emitting element provided on the first substrate 41 is reflected by the side surface S of the optical filter 70, travels to the concave mirror 60, is reflected by the central portion of the concave mirror 60, and is adjacent to the second side. Incident and detected on the substrate 42.

  That is, the viewing angle of light emission / light reception is limited by the dimensions of the optical filter 70 as shown in FIG. As a result, multiple reflection at the concave mirror 60 does not occur, and the light emitted from the light emitting element provided on the first substrate 41 passes through the optical filter 70, is reflected only once by the concave mirror 60, and again the optical filter 70. And enters the second sensor unit provided on the second substrate 42. By reflecting the light emitted from the light emitting element only once by the concave mirror 60, the secular change of the reflectance of the concave mirror 60 can be suppressed to the limit. Furthermore, with such a design, a very small light emitting / receiving device can be realized. For example, a light emitting / receiving device of 30 mm × 30 mm × 16 mm or less, or 15 mm × 15 mm × 10 mm or less can be realized.

[Fourth Embodiment]
FIG. 5 is a conceptual diagram showing a configuration example of a light receiving and emitting device according to the fourth embodiment of the present invention. A signal processing unit (light emitting / receiving control unit) 65 connected to the light emitting element and the sensor unit on the substrate is integrated with the resin mold unit 50.
As shown in FIG. 5, in the light receiving and emitting device according to the fourth embodiment, the light emitting elements 20 and 20 ′ and sensor units 31 and 31 ′ are provided in the first substrate 41 and the second substrate 41 ′, respectively. Yes. However, the fourth embodiment is not limited to this, and similarly to the first and second embodiments, the first substrate is provided with the light emitting element and the first sensor unit, and the second substrate is provided with the second sensor. The structure in which only the part is provided may be used. The configuration of the signal processing unit 45 may be different depending on the structure of the first substrate and the second substrate.

  As shown in FIG. 5, in this light emitting / receiving device, the first substrate 41 and the second substrate 41 ′ are arranged adjacent to each other with their side surfaces (that is, part of the outer peripheral side surface) facing each other and providing a gap. ing. The size of the gap may be a dimension that allows the resin mold portion 50 to enter. For example, when L is the length of the gap between the first substrate and the second substrate (that is, the separation distance between the first substrate and the second substrate), L may be 50 μm. However, when suppressing light transmission through the substrate, the length L of the gap needs to be increased depending on the transmission characteristics of the resin used. As the length L of the gap is increased, the heat conduction is reduced, and a temperature difference between the first substrate and the second substrate is likely to occur. Therefore, it is necessary to optimize this distance when designing the light emitting / receiving device. When a general epoxy resin is used, L may be 100 μm, or 200 μm or more.

As shown in FIG. 5, the light receiving and emitting device according to the fourth embodiment includes a concave mirror as a light reflecting portion on the second main surface 412 side of the first substrate 41 and the second main surface 412 ′ side of the second substrate 41 ′. 60. That is, this light emitting / receiving device is disposed at a position away from each of the first substrate 41 and the second substrate 41 ′, and directs the light emitted from the second main surface 412 of the first substrate 41 toward the second sensor unit 31 ′. And a concave mirror 60 that reflects the light emitted from the second main surface 412 ′ of the second substrate 41 ′ toward the first sensor unit 31.
By integrating the signal processing unit 45 with the resin mold unit 50, the signal processing unit 45 and the light emitting element, and the connection wiring between the signal processing unit 45 and the light receiving element can be shortened. The effects include the following two points.

(1) Reduction of magnetic field generation by driving of light emitting element In many cases, it is necessary to suppress heat generation in order to increase the luminous efficiency of the LED. In particular, as the wavelength is longer, a light-emitting element such as an LED formed of a narrow gap semiconductor has a smaller band gap in the light-emitting layer, and therefore, it is difficult to obtain a strong light emission amount at room temperature. For example, as described later, in the case of a narrow gap semiconductor such as InSb or InAlSb, when driven by direct current, light due to heat generation appears larger than light emission due to recombination. Therefore, it is necessary to apply a pulse instantaneously (for example, several μs to several ms) and receive light only at that moment. Therefore, high-frequency (several hundred Hz to several MHz) electromagnetic noise may be generated from the wiring connecting the drive circuit and the light emitting element.

(2) Noise removal by wiring between the light receiving element and the signal processing circuit (amplifier, etc.).
In particular, in the case of a light receiving element composed of a narrow gap semiconductor, since the output signal is weak, noise due to disturbance or the magnetic field of the current itself flowing through the LED may reduce the S / N ratio of the light receiving element. . In this case, the effect is exhibited by shortening the wiring between the first-stage amplifier and the sensor unit. Therefore, particularly in a long wavelength light emitting and receiving device, the effect can be most exhibited by providing the signal processing unit 65 in the same resin mold unit 50. As an application example of the long wavelength light emitting and receiving device, there are environmental gas sensors such as NO, CO, and CO ₂ . Accordingly, when the present invention is applied to such a gas detection device, a dramatic effect can be obtained.

According to the light emitting / receiving device according to the fourth embodiment, the first substrate 41 and the second substrate 41 ′ are arranged in parallel, whereby the light receiving / emitting device can be further reduced in size. In addition, since the light emitting and receiving device includes the concave mirror 60, the light emitted from the second main surface 412 of the first substrate 41 out of the light output from the first light emitting element 20 (a dashed line) is reflected by the concave mirror 60. Then, it is possible to selectively enter the second sensor unit 31 ′. Of the light output from the second light emitting element 20 ′, the light (not shown) emitted from the second main surface 412 ′ of the second substrate 41 ′ is reflected by the concave mirror 60 and selected by the first sensor unit 31. It becomes possible to make it incident. For this reason, even if a mixture of different substances is mixed in the spatial state, it is possible to measure a characteristic substance with a high S / N ratio.
In the fourth embodiment, as shown in FIG. 5, there is a part of the resin mold portion 50 used for sealing between the first substrate 41 and the second substrate 41 ′. FIG. 5 shows a case where the concave mirror 60 is provided with a supply port 51 for introducing a substance to be detected (for example, a measurement target gas).

[Fifth Embodiment]
FIG. 6 is a conceptual diagram showing a configuration example of a light receiving and emitting device according to the fifth embodiment of the present invention. In the fifth embodiment, unlike the first to fourth embodiments, the concave mirror is designed to be divided into two parts. Thereby, the light collection efficiency can be further improved. This structure can exert its effect when there are many light emitting elements.
As a specific shape, as shown in FIG. 6, a part of the light emitted from the light emitting element 20 on the first substrate 41 is condensed by the first concave mirror 61 and the second substrate 41 ′ 2 is incident on the sensor unit 31 ′. A part of the light emitted from the light emitting element 20 ′ on the second substrate 41 ′ is collected by the second concave mirror 62 and enters the first sensor unit 31 on the first substrate 41.
This structure may be designed so that the optical path from the first substrate 41 to the second substrate 41 ′ is equal to the optical path from the second substrate 41 ′ to the first substrate 41. As a result, the S / N is improved by the two pairs of light emitting / receiving elements, and the temperature difference between the first substrate 41 and the second substrate 41 ′ is reduced (therefore, the temperature difference between the first sensor unit 31 and the second sensor unit 31 ′). Can be realized, and at the same time, a very small and highly accurate light emitting and receiving device can be realized.

<Others>
The present invention is not limited to the embodiment described above. A design change or the like may be added to the embodiment based on the knowledge of a person skilled in the art, and the first to fifth embodiments may be arbitrarily combined, and an aspect in which such a change is added is also included in the present invention. Included in the range.
The light emitting / receiving device of the present invention is not limited to the infrared light receiving / emitting device, and may be, for example, an ultraviolet light receiving / emitting device. In this case, the light emitting unit emits ultraviolet rays, the first sensor unit receives a part of the emitted ultraviolet rays, and the second sensor unit receives the other part of the ultraviolet rays.

  According to the present invention, a smaller light emitting / receiving device having a high S / N ratio that does not require temperature compensation and deterioration compensation can be realized with a simpler configuration.

20, 20 ′ Light emitting element 31 First sensor portion 31 ′, 32 Second sensor portion 41 First substrate 41 ′, 42 Second substrate 45 Signal processing portion 47 Terminal 49 Wire 50 Resin mold portion (an example of a sealing portion)
60 Concave mirror (example of light reflector)
61 First concave mirror 62 Second concave mirror 201, 311, 321 First conductivity type semiconductor layers 202, 312, 322 Second conductivity type semiconductor layers 203, 204, 313, 314, 323, 324 Electrodes 411, 411 ′, 421 First main surface 412, 412 ′, 422 Second main surface 601 Concave surface (mirror surface)

Claims (15)

A first substrate having a first main surface and a second main surface opposite to the first main surface, each having a light emitting element and a first sensor portion formed on the first main surface;
A second substrate having a first main surface and a second main surface opposite to the first main surface, and having a second sensor portion formed on the first main surface;
At least a part of the light emitted from the light emitting element and emitted from the second main surface of the first substrate is directed to the second sensor unit, and is disposed at a position away from each of the first substrate and the second substrate. A light reflecting portion that reflects
A sealing portion that covers and seals the first main surface of the first substrate and the first main surface of the second substrate;
The light reflecting portion is a concave mirror that collects and reflects at least a part of the light, and the first substrate and the second substrate are disposed adjacent to each other with their side surfaces facing each other. . An optical filter that transmits only light in a preset wavelength band;
The optical filter is arranged such that light emitted from the light emitting element and emitted from the second main surface of the first substrate is transmitted through the optical filter twice before entering the second main surface of the second substrate. light emitting and receiving device according to claim 1 disposed. A first substrate having a first main surface and a second main surface opposite to the first main surface, each having a light emitting element and a first sensor portion formed on the first main surface;
A second substrate having a first main surface and a second main surface opposite to the first main surface, and having a second sensor portion formed on the first main surface;
At least a part of the light emitted from the light emitting element and emitted from the second main surface of the first substrate is directed to the second sensor unit, and is disposed at a position away from each of the first substrate and the second substrate. A light reflecting portion that reflects
A sealing portion that covers and seals the first main surface of the first substrate and the first main surface of the second substrate ;
An optical filter that transmits only light in a preset wavelength band , and
The first substrate and the second substrate are disposed adjacent to each other with their side surfaces facing each other ,
The optical filter is arranged such that light emitted from the light emitting element and emitted from the second main surface of the first substrate is transmitted through the optical filter twice before entering the second main surface of the second substrate. Light emitting / receiving device arranged . The light emitting / receiving device according to claim 1, wherein the first substrate and the second substrate are arranged side by side in a state of being separated from each other. The light emitting and receiving device according to claim 4 , wherein a part of the sealing portion is interposed between the first substrate and the second substrate. A signal processing unit for supplying current to the light emitting element and processing each output signal from the first sensor unit and the second sensor unit;
A terminal connected to the signal processing unit,
The signal at least the active surface of the processing unit is sealed is covered with the sealing portion, and wherein at least a portion Claim 1 exposed from the sealing portion of the terminal, according to claim 2, claim 4 And the light emitting and receiving device according to claim 5 . The light receiving and emitting device according to claim 3 , wherein the first substrate and the second substrate are arranged side by side in a state of being separated from each other. The light emitting and receiving device according to claim 7 , wherein a part of the sealing portion is interposed between the first substrate and the second substrate. A signal processing unit for supplying current to the light emitting element and processing each output signal from the first sensor unit and the second sensor unit;
A terminal connected to the signal processing unit,
Wherein at least the active surface of the signal processing unit is sealed is covered with the sealing portion, and wherein at least a portion Claim exposed from the sealing portion of the pin 3, claim 7 and claim 8 The light emitting / receiving device according to any one of the above. The first spacing distance between the substrate and the second substrate, the first substrate and any one of claims 1 to 9 is smaller than the length of the longest side among the sides of the second substrate The light emitting / receiving device according to 1. The light emitting / receiving device according to claim 9 , wherein a distance between a center of gravity of the light emitting surface of the light emitting element and a center of gravity of the light receiving surface of the second sensor unit is within 3 mm. The light reflecting portion is arranged so that a light amount of light incident on the second sensor portion is 0.3 × Pout or more when a light amount of light emitted from the light emitting element is Pout. The light emitting / receiving device according to claim 11 . The light receiving and emitting device according to any one of claims 1 to 12 , wherein the first sensor unit, the second sensor unit, and the light emitting element are made of the same material and have the same laminated structure. The light emitting and receiving device according to claim 13 , wherein the laminated structure is a diode structure including at least two types of layers of a P-type semiconductor and an N-type semiconductor, and includes any material of indium or antimony. The light receiving and emitting device according to any one of claims 1 to 14 , wherein the first substrate and the second substrate are made of the same material.

Images