Light receiving / emitting package
Patent Information
- Application Number
- PCT/JP2026/001636
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-27
- Filing Date
- 2026-01-20
- Publication Date
- 2026-10-01
Smart Images
Figure JP2026001636_01102026_PF_FP_ABST
Abstract
Description
Light-emitting and light-receiving package
[0001] The present invention relates to a light-emitting and light-receiving package in which a light-emitting element and a light-receiving element are housed in the same package.
[0002] Conventionally, for the purpose of obtaining various biological information, a light-emitting and light-receiving element module in which a light-receiving element and a light-emitting element are housed in the same package is known (see, for example, Patent Document 1).
[0003] Japanese Unexamined Patent Publication No. 2016-181650
[0004] However, in the case of the light-emitting and light-receiving element module disclosed in Patent Document 1, the light-receiving element is provided adjacent to the light-emitting element. For this reason, the light-receiving element receives not only the light emitted from an irradiation object (analyte) that has received light from the light-emitting element, but also the light emitted from the light-emitting element that has not reached the analyte. Since the latter light becomes noise in the analysis of the analyte, if the amount of the latter light is not negligible relative to the amount of the former light, the accuracy of the measurement result is affected.
[0005] In view of the above problems, an object of the present invention is to provide a light-emitting and light-receiving package equipped with a light-emitting element and a light-receiving element, in which the light-receiving element is suppressed from receiving light emitted from the light-emitting element before the light reaches an irradiation object.
[0006] The light-receiving and light-emitting package according to the present invention comprises: a base portion having a first surface and a second surface facing a first direction perpendicular to the first surface; a plurality of recesses formed on the first surface of the base portion at intervals and having a bottomed opening shape with the first surface side open; a first light-emitting element housed inside a first recess belonging to the plurality of recesses, with its light-emitting surface facing the opening of the first recess; a first light-receiving element housed inside a second recess belonging to the plurality of recesses but different from the first recess, with its light-receiving surface facing the opening of the second recess, and exhibiting light-receiving sensitivity to light emitted by the first light-emitting element; and a first sealing portion that seals the first light-receiving element within the second recess and is made of a material that exhibits transmittance to light emitted by the first light-emitting element, wherein the inner wall of the first recess exhibits light-shielding properties to light emitted by the first light-emitting element, and the first sealing portion does not reach the inside of the first recess when viewed in the first direction.
[0007] In this specification, "bottomed opening shape" refers to a recessed shape having a bottom and an opening on the side opposite the bottom. Here, "bottom" only needs to be substantially a bottom, and for example, a configuration in which a fine through-hole is formed in a part of the bottom is also within the scope of "bottom".
[0008] The base portion has a first recess and a second recess formed at locations discrete in the planar direction. Light emitted from the first light-emitting element, placed in the first recess, travels through the first recess toward the first surface side where the opening is formed, and irradiates the object to be illuminated. At this time, if the light emitted from the first light-emitting element travels while diverging, it is incident on the inner wall of the first recess formed in the base portion. Since the inner wall of the first recess exhibits light-shielding properties for the light emitted from the first light-emitting element, its travel into the second recess, where the first light-receiving element is formed, is suppressed. In other words, the light-receiving element placed in the second recess is suppressed from receiving light emitted from the first light-emitting element before it reaches the object to be illuminated. As a result, the light received by the light-receiving element is substantially light from the object to be illuminated, improving the accuracy of analysis based on the amount of light received.
[0009] In this specification, "showing light-receiving sensitivity" means that the photoelectric conversion efficiency is 0.1 A / W or higher. The sensitivity characteristics of the photodetector are determined by the material of the photodetector. This information is usually available from the photodetector manufacturer's catalog. If it is not available, it can be measured by a method compliant with JIS C 5991. The photoelectric conversion efficiency is preferably 0.2 A / W or higher, and more preferably 0.3 A / W or higher.
[0010] The first sealing portion seals the first light-receiving element, preventing dirt and moisture from adhering to the light-receiving surface of the first light-receiving element. The first sealing portion is made of a material that is transparent to the light emitted by the first light-emitting element. When light emitted from the object to be illuminated travels through the opening of the second recess into the second recess, it passes through the first sealing portion and is incident on the light-receiving surface of the first light-receiving element.
[0011] In this specification, "exhibiting transmittance" means that the transmittance is 70% or higher. Transmittance can be measured using, for example, a method in accordance with ISO 15368. The transmittance of the first sealing portion to light emitted by the first light-emitting element is preferably 75% or higher, more preferably 80% or higher, and particularly preferably 85% or higher.
[0012] The first sealing portion, which is positioned within the second recess and seals the first light-receiving element, is formed so that it does not reach the inside of the first recess when viewed in the first direction. Therefore, it is possible to suppress the light emitted from the first light-emitting element and traveling in the first direction from entering the first sealing portion and traveling through the first sealing portion toward the second recess before reaching the object to be illuminated.
[0013] As a specific example, the uppermost surface of the first sealing portion in the first direction may be located inside the second recess.
[0014] In the following text, the light emitted from the first light-emitting element may be referred to as "first light" as appropriate. Similarly, the light emitted from the object being illuminated may be referred to as "detection light" as appropriate.
[0015] The inner wall of the first recess exhibits light-shielding properties against the light emitted by the first light-emitting element. In this specification, "exhibiting light-shielding properties" means that the transmittance is less than 3%. More preferably, the inner wall of the first recess has a transmittance of less than 1% to the first light.
[0016] The inner wall of the first recess may have a portion of the base exposed. In this case, the base is made of a material that provides light shielding against the first light.
[0017] The inner wall of the first recess may be formed by a reflective member made of a material that exhibits reflectivity to light emitted from the first light-emitting element, on the surface of the exposed base portion. In this specification, "exhibiting reflectivity" means that the reflectance is 50% or more. The reflectance can be measured, for example, using a method compliant with ISO 15368. By providing a reflective member, even if a portion of the first light emitted from the first light-emitting element is incident on the inner wall of the first recess, it can be reflected once or multiple times by this inner wall and propagated toward the object to be illuminated. In this case, from the viewpoint of increasing the reflection efficiency, the aperture area of the first recess at a position close to the second surface may be smaller than the aperture area at a position close to the first surface.
[0018] The inner wall of the first recess may have a light-absorbing member formed on the exposed surface of the base portion, made of a material that absorbs light emitted from the first light-emitting element. In this specification, "exhibits absorbency" means that the absorption rate is 97% or higher.
[0019] The substrate portion comprises a first substrate, a second substrate having a plurality of discretely spaced through holes, and an adhesive layer that bonds the first substrate and the second substrate together. The plurality of recesses are composed of the through holes and a portion of the first substrate located at the bottom of the through holes. The adhesive layer may be made of a material that exhibits light-shielding properties against the light emitted by the first light-emitting element.
[0020] According to the above structure, a flat plate can be used as the first substrate, and a component with through holes formed in a flat plate can be used as the second substrate. Therefore, the manufacturing process can be simplified.
[0021] Furthermore, since the adhesive layer used to bond the first substrate and the second substrate is made of a material that exhibits light-shielding properties against the light emitted by the first light-emitting element, even if the light emitted from the first light-emitting element (first light) propagates while diverging, it is suppressed from passing through the adhesive and propagating into the second recess.
[0022] The first light-emitting element may be positioned such that, when viewed in the first direction, it is offset from the center of the first recess towards the first light-receiving element.
[0023] Light emitted from the first light-emitting element (first light) passes through the opening of the first recess formed on the first surface and irradiates the object to be irradiated. When the object to be irradiated receives the first light, it emits detection light of an intensity derived from the properties of the target substance contained in the object, and this detection light is received by the first light-receiving element located in the second recess.
[0024] In this case, when viewed from the first direction, if the first light-receiving element is located far from the first light-emitting element, the proportion of detected light emitted from the illuminated object that does not enter the first light-receiving element increases. Conversely, when viewed from the first direction, by bringing the first light-emitting element closer to the first light-receiving element, the ratio of the amount of light that enters the first light-receiving element to the amount of detected light emitted from the illuminated object can be increased.
[0025] The light-receiving package includes a second sealing portion made of a material that seals the first light-emitting element within the first recess and exhibits transparency to the light emitted by the first light-emitting element, wherein the second sealing portion does not extend to the inside of the second recess when viewed in the first direction.
[0026] The light-receiving package includes a second sealing portion that encloses the first light-emitting element, thereby preventing dirt and moisture from adhering to the light-emitting surface of the first light-emitting element. The second sealing portion is made of a material that is transparent to the first light emitted by the first light-emitting element. Therefore, the first light travels in the first direction within the second sealing portion, is extracted to the outside of the first recess, and irradiates the object to be irradiated.
[0027] Furthermore, this second sealing portion is formed so that it does not reach the inside of the second recess when viewed in the first direction. Therefore, it is possible to suppress the light emitted from the first light-emitting element and traveling in the first direction from traveling through the second sealing portion toward the second recess before reaching the object being illuminated.
[0028] The second sealing portion may be made of the same material as the first sealing portion.
[0029] The light-receiving package may include a first current-carrying portion made of a conductive material at a portion of the substrate, and a wire connecting the first current-carrying portion and a pad electrode formed on the light-emitting surface side of the first light-emitting element, wherein the wire may extend in a direction away from the first light-receiving element.
[0030] The detection light received by the first photodetector is the light emitted from the object after the light emitted from the first light-emitting element (first light) has irradiated the object. Therefore, the light from the first light that diverges and propagates away from the first photodetector does not contribute much to the generation of the detection light received by the first photodetector. Thus, by extending the wire connected to the pad electrode formed on the light-emitting surface side of the first light-emitting element in a direction away from the first photodetector, it is possible to suppress the decrease in the intensity of the detection light emitted from the object even if a part of the first light is blocked by the wire.
[0031] The first energized portion is typically formed at the bottom of the first recess and located outside the first light-emitting element when viewed in the first direction.
[0032] Furthermore, the light-receiving package includes a second energizing portion formed within the first recess on the surface of the first light-emitting element opposite to the light-emitting surface, and an insulating portion positioned within the first recess, viewed in the first direction, between the first energizing portion and the second energizing portion, wherein the first energizing portion and the second energizing portion are each connected to the same side surface of the base portion.
[0033] This configuration allows the power supply to be connected from the same side of the base, simplifying the mounting process. The insulating portion may also be composed of a part of the base made of an insulating material.
[0034] Furthermore, the second energizing portion may extend to the second surface of the base portion.
[0035] According to this, the second power supply section can be used for both power supply and heat dissipation purposes.
[0036] The first light-emitting element has a linear electrode formed on the light-emitting surface side, and the wire may extend along the linear electrode such that it substantially overlaps the linear electrode when viewed in the first direction.
[0037] In the preceding description, when viewed in the first direction, it means that 10% or more of the portion of the wire that passes through the region where the linear electrode is formed overlaps with the linear electrode when viewed in the first direction. More typically, when viewed in the first direction, the angle between the direction in which the portion of the wire that passes through the region where the linear electrode is formed extends and the direction in which the linear electrode extends is 10° or less, and the two directions are substantially parallel.
[0038] From the viewpoint of increasing the luminescence efficiency of the first light-emitting element, a linear electrode extending linearly (linear electrode) may be formed on the light-emitting surface side. This allows the current flowing through the first light-emitting element to be spread in the planar direction, thereby suppressing localized light emission and increasing luminescence efficiency. However, the region where the linear electrode is formed forms a non-luminescent region on the light-emitting surface of the first light-emitting element. Therefore, by extending the wire along the linear electrode, it is possible to prevent the wire from further obstructing the propagation of the first light.
[0039] Improving luminous efficiency by forming linear electrodes on the light-emitting surface is particularly effective when the size of the light-emitting surface of the first light-emitting element is large. Specifically, it is effective when the length of at least one side of the outer edge of the light-emitting surface is 0.5 mm or more, even more effective when it is 0.7 mm or more, and particularly effective when it is 0.9 mm or more.
[0040] The linear electrode may be formed along the outer edge of the light-emitting surface. In this case, the portion of the wire that passes through the region where the linear electrode is formed when viewed in the first direction may also extend along the outer edge of the light-emitting surface.
[0041] The light receiving and emitting package may comprise a plurality of first light emitting elements having mutually different emission wavelengths. To give a specific example, the plurality of first light emitting elements may include an element with a peak emission wavelength of 660 nm, an element with a peak emission wavelength of 805 nm, and an element with a peak emission wavelength of 1,450 nm.
[0042] The plurality of first light emitting elements having mutually different wavelengths may be housed inside the same first recess, or may be housed inside different first recesses. In the latter case, the light receiving and emitting package comprises a plurality of said first recesses, and among the plurality of said first light emitting elements respectively housed in the plurality of said first recesses, at least two or more of said first light emitting elements may have mutually different peak emission wavelengths.
[0043] Here, when viewed in the first direction, at least one of the plurality of recesses has a different shape compared to the other recesses, and when rotated in a direction parallel to the first surface with the center of the first surface as a reference, the shape formed by the plurality of recesses may be rotationally asymmetric.
[0044] According to this configuration, the orientation of the light receiving and emitting package during mounting can be easily recognized based on the shape of the recesses.
[0045] The first light receiving element has a pad electrode formed on the light receiving surface side, the plurality of recesses are arranged along a plurality of rows and a plurality of columns when viewed in the first direction, the second recess is arranged at a position corresponding to a corner among the plurality of recesses when viewed in the first direction, and the pad electrode of the first light receiving element may be formed at a position distant from the first light emitting element on the light receiving surface side.
[0046] As described above, the detection light received by the first light-receiving element is light emitted from an irradiation target after the light (first light) emitted from the first light-emitting element irradiates the irradiation target. That is, most of the detection light incident on the light-receiving surface of the first light-receiving element travels while having a vector component directed from the first light-emitting element toward the first light-receiving element when viewed in the first direction (hereinafter referred to as "vector component Va" herein). Conversely, among the detection light incident on the light-receiving surface of the first light-receiving element, the proportion of light that travels toward the first light-receiving element from a position far from the first light-emitting element and has a vector component opposite to vector component Va is extremely low. Therefore, by forming the pad electrode at a position far from the first light-emitting element on the light-receiving surface side, the amount of detection light that cannot be received by the pad electrode becomes limited.
[0047] The light-emitting and light-receiving package may be provided with a plurality of light-receiving elements having mutually different light-receiving sensitivities.
[0048] That is, the light-emitting and light-receiving package comprises: a third recess and a fourth recess belonging to the plurality of recesses; a second light-emitting element accommodated inside the third recess with its light-emitting surface facing a direction toward the opening of the third recess, the peak emission wavelength of which is different from that of the first light-emitting element; a second light-receiving element accommodated inside the fourth recess with its light-receiving surface facing a direction toward the opening of the fourth recess; and a third sealing portion that seals the second light-receiving element inside the fourth recess, wherein the first light-receiving element does not exhibit light-receiving sensitivity to light emitted by the second light-emitting element, the second light-receiving element exhibits light-receiving sensitivity to light emitted by the second light-emitting element, and the third sealing portion may not reach the inside of the third recess when viewed in the first direction.
[0049] In the present specification, the phrase "does not exhibit light-receiving sensitivity" means exhibiting a relative sensitivity value of less than 5% relative to the maximum sensitivity value. It is preferable to exhibit a relative sensitivity value of less than 3% relative to the maximum sensitivity value, and more preferable to exhibit a relative sensitivity value of less than 1% relative to the maximum sensitivity value.
[0050] According to the present invention's light-receiving and light-receiving package, even when a light-emitting element and a light-receiving element are mounted in the same package, it is possible to suppress the reception of light emitted from the light-emitting element by the light-receiving element before it reaches the object to be illuminated.
[0051] This is a schematic perspective view showing the configuration of one embodiment of the light-receiving package of the present invention. This is a schematic exploded perspective view of the light-receiving package 1 shown in Figure 1. This is a schematic plan view of the light-receiving package 1 shown in Figure 1 when viewed in the -Z direction. This is a schematic plan view of the first substrate 11 shown in Figure 2. This is a cross-sectional view taken along the line X1-X1 in Figure 3. This is a drawing from Figure 5 onwards, with some elements omitted. This is a schematic plan view of the light-receiving package 1 shown in Figure 1 when viewed in the +Z direction. This is a schematic drawing showing an example of using the light-receiving package 1 for sensing an object to be illuminated. This is a drawing showing a light-receiving package considered as a comparison, following Figure 8. This is a partially enlarged view of Figure 8. This is a drawing showing variations in the formation of the first sealing portion 51. This is a drawing showing variations in the formation of the first sealing portion 51. This is a partially enlarged view of Figure 3. This is a partially enlarged view of Figure 4. This is a partially enlarged view of Figure 3. This is a schematic cross-sectional view showing the configuration of a modified example of the light-receiving package, following Figure 6. This is a schematic plan view illustrating a modified configuration of the light-receiving package, following Figure 7. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package. This is a schematic plan view illustrating another modified configuration of the light-receiving package 1. This is a cross-sectional view taken along the line Y1-Y1 in Figure 18. This is a cross-sectional view taken along the line X2-X2 in Figure 18.
[0052] Embodiments of the light-receiving and light-emitting package according to the present invention will be described with appropriate reference to the drawings. Note that the following drawings are schematic representations, and the dimensional ratios and number of elements shown in the drawings do not necessarily correspond to the actual dimensional ratios and number of elements. Furthermore, for the sake of clarity, dimensional ratios may be shown differently in the drawings.
[0053] Figure 1 is a schematic perspective view of the light-receiving package of this embodiment. Figure 2 is a schematic exploded perspective view of the light-receiving package 1 shown in Figure 1. Figure 3 is a schematic plan view of the light-receiving package 1 shown in Figure 1. However, for illustrative purposes, the first sealing portion 51 and the second sealing portion 52, which will be described later with reference to Figure 5, are omitted from the illustration in Figures 2 and 3.
[0054] The light-receiving package 1 comprises a base portion 3. The base portion 3 has a first surface 3a and a second surface 3b opposite to the first surface 3a. In this embodiment, the base portion 3 is constructed by bonding a first substrate 11 and a second substrate 12 together.
[0055] In the following, the X-Y-Z coordinate system, in which the direction in which the first surface 3a and the second surface 3b face each other is defined as the Z-axis, and the plane perpendicular to this Z-axis is defined as the X-Y plane, will be referred to as appropriate. In the following description, when expressing a direction, positive and negative directions will be distinguished by adding a sign, such as "+X direction" and "-X direction". When expressing a direction without distinguishing between positive and negative directions, it will simply be written as "X direction". That is, in this specification, when simply written as "X direction", both "+X direction" and "-X direction" are included. The same applies to the Y direction and Z direction. In this specification, the Z direction corresponds to the "first direction".
[0056] Multiple recesses 20 are formed on the first surface 3a side of the base portion 3, with the first surface 3a side being open. Multiple recesses 20 are formed with spacing between them in the direction along the X-Y plane. Figure 1 shows an example in which four recesses 20 are arranged in a 2x2 arrangement. All of the multiple recesses 20 have a bottomed opening shape.
[0057] As shown in Figure 2, in the light-receiving package 1 of this embodiment, a plurality of through holes 14 are discretely formed in the second substrate 12. When this second substrate 12 is bonded to the first substrate 11, a plurality of recesses 20 originating from the plurality of through holes 14 are formed.
[0058] The light-receiving package 1 includes a first light-emitting element 31. In this embodiment, there are three first light-emitting elements 31, each housed in a different recess 20. Hereafter, the recess 20 in which the first light-emitting elements 31 are housed will be referred to as the "first recess 21".
[0059] The first light-emitting element 31 is installed within the first recess 21 with its light-emitting surface facing the opening of the first recess 21, i.e., the first surface 3a.
[0060] The first light-emitting element 31 is a solid-state light source element, typically an LED. When distinguishing between the three first light-emitting elements 31, they may be denoted as 31a, 31b, and 31c. Specifically, as shown in Figures 2 and 3, the first light-emitting element 31 located on both the -X and -Y sides may be denoted as "first light-emitting element 31a", the first light-emitting element 31 adjacent to the first light-emitting element 31a on the +X side may be denoted as "first light-emitting element 31b", and the first light-emitting element 31 adjacent to the first light-emitting element 31b on the +Y side may be denoted as "first light-emitting element 31c". When these first light-emitting elements 31a, 31b, and 31c are not distinguished, they are simply referred to as "first light-emitting element 31".
[0061] In this embodiment, the first light-emitting element 31a, the first light-emitting element 31b, and the first light-emitting element 31c have different emission wavelengths. For example, the peak emission wavelength of the first light-emitting element 31a is 660 nm, the peak emission wavelength of the first light-emitting element 31b is 805 nm, and the peak emission wavelength of the first light-emitting element 31c is 1,450 nm.
[0062] The light-receiving package 1 includes a first light-receiving element 41. The first light-receiving element 41 is housed in a recess 20 different from the recess 20 in which the first light-emitting element 31 is housed. Hereinafter, the recess 20 in which the first light-receiving element 41 is housed will be referred to as the "second recess 22".
[0063] The first light-receiving element 41 is installed in the second recess 22 with its light-receiving surface facing the opening of the second recess 22, i.e., the first surface 3a.
[0064] The first light-receiving element 41 indicates the light-receiving sensitivity to the light emitted by the first light-emitting element 31. The first light-receiving element 41 is typically a photodiode, but may also be a phototransistor. In this embodiment, the first light-emitting element 31 includes a first light-emitting element 31a, a first light-emitting element 31b, and a first light-emitting element 31c, each having different emission wavelengths. Therefore, in this embodiment, the first light-receiving element 41 has light-receiving sensitivity to the light emitted by the first light-emitting element 31a, the first light-emitting element 31b, and the first light-emitting element 31c.
[0065] The first substrate 11 is preferably made of a material that exhibits light-shielding properties against the light emitted by the first light-emitting element 31. From the viewpoint of reducing manufacturing costs, it is more preferable to make the first substrate 11 from the same material as the second substrate 12.
[0066] The first light-receiving element 41 is sealed within the second recess 22 by the first sealing portion 51. In this embodiment, the first light-emitting element 31 is sealed within the first recess 21 by the second sealing portion 52.
[0067] The first sealing portion 51 is made of a material that is transparent to the light emitted by the first light-emitting element 31. In the light-receiving package 1 of this embodiment, the first sealing portion 51 is made of a material that is transparent to the light emitted by the first light-emitting element 31a, the first light-emitting element 31b, and the first light-emitting element 31c. As the first sealing portion 51, a resin material such as epoxy resin or silicone resin, or a glass material can be used.
[0068] The second sealing portion 52 is made of a material that is transparent to the light emitted by the first light-emitting element 31. More specifically, the second sealing portion 52 is made of a material that is transparent to the light emitted by the first light-emitting element 31 that it seals. The second sealing portion 52 may be made of the same material as the first sealing portion 51.
[0069] The height of the outermost surface of the first sealing portion 51 housed in the second recess 22, and the height of the outermost surface of the second sealing portion 52 housed in the first recess 21, will be described later with reference to Figure 8.
[0070] Figure 4 is a schematic plan view of the first substrate 11 shown in Figure 2, as seen in the -Z direction.
[0071] As shown in Figure 4, a first energizing portion 32 and a second energizing portion 33 are formed on the +Z side surface of the first substrate 11 for supplying current to the first light-emitting element 31. Preferably, the first substrate 11 is made of an insulating material. As specific materials for the first substrate 11, rigid substrates such as glass epoxy and glass composite, FPC substrates such as polyimide, and ceramic substrates such as aluminum nitride, silicon nitride, and alumina can be used.
[0072] Both the first energized portion 32 and the second energized portion 33 are formed on the +Z side surface of the first substrate 11, with a material layer exhibiting high conductivity. Known conductive materials can be used for the first energized portion 32 and the second energized portion 33, typically copper.
[0073] The second energizing portion 33 is formed on the +Z side surface of the first substrate 11, and the first light-emitting element 31 is installed on its upper surface. The first energizing portion 32 is located on the +Z side surface of the first substrate 11, outside the first light-emitting element 31, with an insulating portion 34 in between. The insulating first substrate 11 may also serve as the insulating portion 34, or an insulating portion 34 made of a different insulating material may be formed on the upper surface of the first substrate 11.
[0074] The first light-emitting element 31 has its +Z-side surface as the light-emitting surface, and a pad electrode 36 (not shown in Figure 4, see Figure 6) is formed on this light-emitting surface. The pad electrode 36 and the first energizing section 32 are connected by a wire 35.
[0075] For example, the first energizing section 32 is the cathode of the first light-emitting element 31, and the second energizing section 33 is the anode of the first light-emitting element 31. However, the two may have opposite polarities.
[0076] In this embodiment, both the first energizing section 32 and the corresponding second energizing section 33 extend along the same side surface of the first substrate 11. Specifically, as shown in Figure 4, the first energizing section 32 and the second energizing section 33 for supplying current to the first light-emitting element 31a both extend within the -Y region of the -X side surface of the first substrate 11 and are connected to electrode terminals 37 and 38, respectively. Similarly, the first energizing section 32 and the second energizing section 33 for supplying current to the first light-emitting element 31b both extend within the -Y region of the +X side surface of the first substrate 11. The first energizing section 32 and the second energizing section 33 for supplying current to the first light-emitting element 31c both extend within the +Y region of the +X side surface of the first substrate 11.
[0077] As shown in Figure 4, a first current-carrying section 42 and a second current-carrying section 43 are formed on the +Z side surface of the first substrate 11 for conducting current from the first photodetector 41. Both the first current-carrying section 42 and the second current-carrying section 43 are made of a material layer exhibiting high conductivity, which is formed on the +Z side surface of the first substrate 11. Known conductive materials can be used for the first current-carrying section 42 and the second current-carrying section 43, and are typically copper.
[0078] The second energizing section 43 is formed on the +Z side surface of the first substrate 11, and the first light-receiving element 41 is installed on its upper surface. The first energizing section 42 is located on the +Z side surface of the first substrate 11, outside the first light-receiving element 41, with an insulating section 44 in between. Similar to the insulating section 34, the insulating first substrate 11 may also serve as the insulating section 44.
[0079] The first light-receiving element 41 has its +Z side as the light-receiving surface, and a pad electrode 46 (not shown in Figure 4, see Figure 14) is formed on this light-receiving surface. The pad electrode 46 and the first energizing part 42 are connected by a wire 45.
[0080] Figure 5 is a cross-sectional view taken along the line X1-X1 in Figure 3. Figure 6 is a view from Figure 5 with the first sealing portion 51 and the second sealing portion 52 omitted.
[0081] As shown in Figures 5 and 6, the first substrate 11 and the second substrate 12 are bonded together via an adhesive layer 16. The adhesive layer 16 is made of a material that exhibits light-shielding properties against the light emitted by the first light-emitting element 31. As the material for the adhesive layer 16, an acrylic, epoxy, or silicone adhesive can be used, which contains a dispersed material that does not transmit light at the wavelength of light emitted by the first light-emitting element 31, such as carbon black or a pigment, or an adhesive that exhibits light absorption properties against the light emitted by the first light-emitting element 31.
[0082] As described above, the first sealing portion 51 that seals the first light-receiving element 41 is located within the second recess 22. Furthermore, this first sealing portion 51 is formed so as not to enter the first recess 21. More specifically, when viewed in the -Z direction, the first sealing portion 51 does not reach the inside of the first recess 21. In this embodiment, the uppermost surface 51a of the first sealing portion 51 is located inside the second recess 22.
[0083] As described above, the second sealing portion 52 that seals the first light-emitting element 31 is located within the first recess 21. Furthermore, this second sealing portion 52 is formed so as not to enter the second recess 22. More specifically, when viewed in the -Z direction, the second sealing portion 52 does not reach the inside of the second recess 22. In this embodiment, the uppermost surface 52a of the second sealing portion 52 is located inside the first recess 21. However, the second sealing portion 52 may enter an adjacent first recess 21 in which another first light-emitting element 31 is housed.
[0084] In this embodiment, as shown in Figure 6, a reflective member 17 is formed on the inner wall of the first recess 21. The reflective member 17 is made of a material that exhibits reflectivity to light emitted by the first light-emitting element 31. As the material of the reflective member 17, one or more materials belonging to the group consisting of aluminum, gold, silver, titanium oxide, nickel, and chromium can be used.
[0085] Because the reflective member 17 is formed on the inner wall of the first recess 21, the inner wall of the first recess 21 does not substantially transmit the light emitted by the first light-emitting element. In other words, the inner wall of the first recess 21 exhibits light-shielding properties against the light emitted by the first light-emitting element 31.
[0086] In this embodiment, a reflective member 17 is also formed on the inner wall of the second recess 22.
[0087] As shown in Figure 6, the first recess 21 has a smaller opening area on the -Z side (i.e., the second surface 3b side: see Figure 1) than on the +Z side (i.e., the first surface 3a side: see Figure 1). More specifically, the first recess 21 has a tapered shape in which the opening area decreases as it proceeds in the -Z direction. This allows light emitted from the first light-emitting element 31 within the first recess 21, which propagates diverging and enters the inner wall of the first recess 21, to be guided in the +Z direction while being reflected once or multiple times.
[0088] In this embodiment, the second recess 22 also exhibits a tapered shape similar to that of the first recess 21.
[0089] As described above, the first light-emitting element 31 is installed on the upper surface of the second energizing section 33 formed on the first substrate 11. The first energizing section 32 formed on the first substrate 11 is connected to a pad electrode 36 formed on the light-emitting surface (+Z side) of the first light-emitting element 31 by a wire 35. As shown in Figure 6, this wire 35 extends in a direction away from the first light-receiving element 41.
[0090] As described above, the first light-receiving element 41 is installed on the upper surface of the second energizing section 43 formed on the first substrate 11. The first energizing section 42 formed on the first substrate 11 is connected to the pad electrode 46 formed on the light-receiving surface (+Z side surface) of the first light-receiving element 41 by a wire 45.
[0091] Figure 7 is a schematic plan view of the light-receiving package 1 as seen in the -Z direction. In other words, Figure 7 corresponds to a plan view of the back surface of the first substrate 11, or in other words, the second surface 3b. As shown in Figure 7, the first energizing section 32 and the second energizing section 33 for supplying current to the first light-emitting element 31, and the first energizing section 42 and the second energizing section 43 for allowing current from the first light-receiving element 41 to flow, are exposed on the back surface of the first substrate 11. Therefore, by placing the -Z side surface (second surface 3b) of the light-receiving package 1 at a predetermined installation location where wiring is formed, the light-receiving package 1 can be mounted.
[0092] In this embodiment, as shown in Figures 6 to 7, a heat dissipation section 61 is formed on the -Z side surface of the first substrate 11. This heat dissipation section 61 is made of a material with high thermal conductivity, typically copper, but other materials such as copper-containing composite materials (e.g., Cu / Cu-Mo / Cu clad material) or aluminum nitride can also be used.
[0093] Figure 8 is a schematic diagram illustrating an example of using the light-receiving package 1 for sensing an object to be irradiated. Light emitted from the first light-emitting element 31 (first light L1) passes through the second sealing part 52 and then irradiates the object to be irradiated 5. The object to be irradiated 5 emits light (detection light L2) that exhibits a spectrum corresponding to the light-receiving characteristics of the substance to be detected. This detection light L2 passes through the first sealing part 51 and then enters the first light-receiving element 41. The first light-receiving element 41 generates an electromotive force corresponding to the light intensity of the detection light L2 and flows a current. Depending on the amount of this current, the presence and concentration of the substance to be detected contained in the object to be irradiated 5 are detected.
[0094] Here, let's consider the case where, as in the light-receiving package 90 shown in Figure 9, the sealing portion 91 that seals the first light-receiving element 41 enters the first recess 21, and the first light-emitting element 31 is also integrally sealed. In this case, it is conceivable that some of the light La of the first light L1 emitted from the first light-emitting element 31 travels through the sealing portion 91 and enters the second recess 22, and then reaches the first light-receiving element 41 without being incident on the object to be irradiated 5. In this case, the light La becomes noise, and there is a risk that the light reception intensity at the first light-receiving element 41 will not accurately reflect the light reception characteristics originating from the target substance contained in the object to be irradiated 5.
[0095] In contrast, as shown in Figure 8, the first sealing portion 51 that seals the first light-receiving element 41 within the second recess 22 is formed so as not to reach the first recess 21, thereby suppressing the propagation of light like the light La shown in Figure 9.
[0096] Figure 10 is a partially enlarged view of Figure 8. As the light emitted from the first light-emitting element 31 propagates while diverging, some of the light L1a may be incident on the inner wall of the first recess 21. However, as described above, in this embodiment, a reflective member 17 is formed on the inner wall of the first recess 21, so the light L1a is reflected by the inner wall of the first recess 21 and propagates toward the object to be illuminated located on the +Z side (see Figure 8). In other words, it is prevented that the light L1a will travel in a straight line into the second recess 22.
[0097] From the viewpoint of preventing light emitted from the first light-emitting element 31 from directly entering the second recess 22, the inner wall of the first recess 21 only needs to have light-shielding properties with respect to the light emitted from the first light-emitting element 31. In other words, the inner wall of the first recess 21 may be reflective with respect to the light emitted from the first light-emitting element 31, as described above, or it may be absorbing. For example, a light-absorbing member may be formed on the inner wall of the first recess 21, such as a sheet material mixed with a black pigment such as carbon black, or a pigment that absorbs the wavelength of light emitted by the first light-emitting element 31, or an acrylic, epoxy, or silicone adhesive that absorbs the light emitted by the first light-emitting element 31. Alternatively, the second substrate 12 that constitutes the inner wall of the first recess 21 may be formed of a material that absorbs the light emitted from the first light-emitting element 31.
[0098] As shown in Figure 10, the light emitted from the first light-emitting element 31 propagates while diverging, so some of the light Lb may enter the adhesive layer 16. However, as described above, the adhesive layer 16 is made of a material that is light-shielding to the light emitted by the first light-emitting element 31, so the light Lb is prevented from propagating through the adhesive layer 16 and reaching the second recess 22.
[0099] Furthermore, the detection light L2 (see Figure 8) emitted from the object to be illuminated 5 (see Figure 8) also diverges as it propagates, so there is a possibility that some of the light L2a may be incident on the inner wall of the second recess 22. However, in the example shown in Figure 10, a reflective member 17 is also formed on the inner wall of the second recess 22, so the light can be reflected by the inner wall of the second recess 22 and guided to the first light-receiving element 41.
[0100] Figures 11A to 11C are diagrams showing variations in the formation of the first sealing portion 51.
[0101] As shown in Figures 11A and 11B, the uppermost surface 51a of the first sealing portion 51 may be located on the -Z side of the first surface 3a, and more specifically, it may be formed in a recessed shape such that the height of the center is lower than that of the outer circumference. This makes it possible to avoid as much as possible the first sealing portion 51 that seals the first light-receiving element 41 reaching the inside of the first recess 21 where the first light-emitting element 31 is housed when it is poured into the second recess 22.
[0102] An example of dimensions in the structure shown in Figure 11A is as follows: The length (height) in the Z direction of the first light-emitting element 31 and the first light-receiving element 41 is approximately 0.15 mm to 0.3 mm. The height of the inner wall of the second recess 22 is approximately 0.5 mm to 0.7 mm. The difference in height in the Z direction between the uppermost surface (first surface 3a) of the second recess 22 and the lowest point of the uppermost surface 51a of the first sealing portion 51 is greater than 0 mm and approximately 0.1 mm.
[0103] Note that Figure 11B differs from Figure 11A in that the height position of the uppermost surface 52a of the second sealing portion 52 is lower than the height position of the uppermost surface 51a of the first sealing portion 51. For example, by making the opening area of the second recess 22 larger than the opening area of the first recess 21, even if equal amounts of the first sealing portion 51 and the second sealing portion 52 are poured in, it is possible to avoid as much as possible the first sealing portion 51 reaching the inside of the first recess 21.
[0104] However, the present invention does not exclude the configuration in which the height position of the uppermost surface 51a of the first sealing portion 51 is located on the +Z side of the first surface 3a. For example, as shown in Figure 11C, even if the height position of the uppermost surface 51a of the first sealing portion 51 is located on the +Z side of the first surface 3a, as long as the first sealing portion 51 does not reach the inside of the first recess 21, the emergence of light following a propagation path such as light La as described above, with reference to Figure 9, can be suppressed.
[0105] Figure 12 is a partially enlarged view of Figure 3. The center c41 of the first light-receiving element 41 is offset towards the first light-emitting element 31 compared to the center c22 of the second recess 22 (deviation d41). Similarly, the center c31 of the first light-emitting element 31 is offset towards the first light-receiving element 41 compared to the center c21 of the first recess 21 (deviation d31). This increases the amount of light that the detection light L2 (see Figure 8) emitted from the object to be illuminated 5 is incident on the light-receiving surface of the first light-receiving element 41. However, the embodiment shown in Figure 12 is a preferred example, and the present invention does not exclude an embodiment in which the center c41 of the first light-receiving element 41 coincides with the center c22 of the second recess 22. Similarly, the present invention does not exclude an embodiment in which the center c31 of the first light-emitting element 31 coincides with the center c21 of the first recess 21.
[0106] Figure 13 is a partially enlarged view of Figure 4. The first light-emitting element 31 may have a linear electrode (linear electrode 39) on its light-emitting surface (the +Z side surface). This linear electrode 39 is formed to increase the luminescence efficiency by spreading the current flowing through the first light-emitting element 31 in a direction parallel to the X-Y plane, and is particularly effective when the size of the first light-emitting element 31 is large. The linear electrode 39 is electrically connected to the pad electrode 36.
[0107] In this case, it is preferable to extend the wire 35, which electrically connects the pad electrode 36 and the first energizing part 32, along the linear electrode 39. More specifically, the wire 35 extends along the linear electrode 39 such that it substantially overlaps the linear electrode 39 when viewed in the Z direction.
[0108] The area of the light-emitting surface of the first light-emitting element 31 where the linear electrode 39 is located originally forms a non-light-emitting region. Therefore, by positioning the wire 35 so that it substantially overlaps the linear electrode 39 when viewed in the Z direction, it is possible to prevent the wire from further obstructing the propagation of the first light L1 (see Figure 8) emitted from the first light-emitting element 31.
[0109] Figure 14 is a partially enlarged view of Figure 3. Following Figure 4, Figure 14 shows the first energizing section 42, the second energizing section 43, and the insulating section 44.
[0110] The first light-receiving element 41 has a pad electrode 46 on its light-receiving surface (the +Z side surface), and the pad electrode 46 and the first energizing part 42 are connected via a wire 45. As shown in Figure 14, the pad electrode 46 is formed near the -X side and +Y side corners on the light-receiving surface. This position is far from the adjacent first light-emitting element 31 on the light-receiving surface.
[0111] By forming the pad electrode 46 at a position far from the adjacent first light-emitting element 31, the amount by which the pad electrode 46 obstructs the first light-receiving element 41 from receiving the detected light L2 (see Figure 8) can be suppressed.
[0112] [Modified Versions] Modified versions of the light-receiving and light-emitting package 1 will be described below with reference to the drawings.
[0113] (1) Figures 15 and 16 are schematic diagrams showing modified configurations of the light-receiving package 1. Figure 15 is a schematic cross-sectional view following Figure 6, and Figure 16 is a schematic plan view following Figure 7.
[0114] As shown in Figure 15, in this modified example, the second energized section 33 on which the first light-emitting element 31 is installed on the upper surface, and the second energized section 43 on which the first light-receiving element 41 is installed on the upper surface, are exposed on the back side of the first substrate 11. More specifically, in the Z direction, the second energized section 33 has a region that includes the area where the first light-emitting element 31 is located, which penetrates the first substrate 11 and is exposed on the back side. The same applies to the second energized section 43 on which the first light-receiving element 41 is installed on the upper surface. In this case, as shown in Figure 16, the second energized section 33 and the second energized section 43 perform a heat dissipation function similar to the heat dissipation section 61 shown in Figure 7, in addition to their energizing function.
[0115] (2) Figures 17A to 17I are diagrams showing modified shapes of the multiple recesses 20, and all are schematic plan views of the light-receiving package 1 as seen in the -Z direction.
[0116] The shape of the multiple recesses 20 (first recess 21, second recess 22) when viewed in the -Z direction is not limited to a circular shape. For example, as shown in Figure 17A, the multiple recesses 20 (first recess 21, second recess 22) may have a quadrilateral shape. Here, "quadrilateral shape" includes shapes that have curves in part but can be considered to have a quadrilateral shape overall.
[0117] The number of recesses 20 formed is arbitrary. For example, as shown in Figure 17B, five recesses 20 may be formed, including four first recesses 21 and one second recess 22. Alternatively, as shown in Figure 17C, nine recesses 20 may be formed, including eight first recesses 21 and one second recess 22.
[0118] The shape of the base portion 3 when viewed in the Z direction is arbitrary. For example, as shown in Figure 17D, the base portion 3 may have a triangular shape when viewed in the Z direction. Note that Figure 17D shows an example in which four recesses 20 are formed, including three first recesses 21 and one second recess 22.
[0119] Furthermore, as shown in Figures 17E to 17G, multiple recesses 20 may be arranged in a row. Figure 17E shows an example in which two recesses 20 are formed, including one first recess 21 and one second recess 22. The modified light-receiving package 1 shown in Figure 17E is equipped with one first light-emitting element 31 and one first light-receiving element 41. In Figure 17E, the state in which the center of the first light-emitting element 31 is offset toward the first light-receiving element 41 than the center of the first recess 21, and the center of the first light-receiving element 41 is offset toward the first light-emitting element 31 than the center of the second recess 22 is exaggerated in the illustration.
[0120] Figure 17F shows an example in which three recesses 20, including two first recesses 21 and one second recess 22, are arranged in a row. The modified light-receiving package 1 shown in Figure 17F is equipped with two first light-emitting elements 31 and one first light-receiving element 41. In this case, it is preferable that the two first light-emitting elements 31 are arranged so as to sandwich the first light-receiving element 41.
[0121] Figure 17G shows an example in which four recesses 20, including two first recesses 21 and two second recesses 22, are arranged in a row. As shown in Figure 17G, some of the recesses 20 may have a different shape from the others.
[0122] As shown in Figure 17H, multiple first light-emitting elements 31 may be arranged within the same first recess 21. In Figure 17H, an example is shown in which one first recess 21 housing multiple first light-emitting elements 31 and three second recesses 22, each housing one first light-receiving element 41.
[0123] As shown in Figure 17I, when rotated on the X-Y plane with respect to the center, the multiple recesses 20 may exhibit a rotationally asymmetric shape when viewed in the -Z direction. In the example shown in Figure 17I, the first recess 21 located on the -X and -Y sides has a notch at the corner located on the -X and -Y sides. This makes it easier to recognize the orientation when mounting the light-receiving package 1.
[0124] Furthermore, as shown in Figure 17I, some of the multiple recesses 20 may contain surplus recesses 26 in which neither light-emitting elements nor light-receiving elements are housed. This allows for changing the number of light-emitting elements or light-receiving elements mounted while maintaining a common package design.
[0125] <3> Figures 18 to 20 are schematic diagrams showing the configuration of another modified example of the light-receiving package 1. Figure 18 is a schematic plan view showing the structure of the light-receiving package 1 following Figures 17A to 17I. Figure 19 is a cross-sectional view of Figure 18 taken along the line Y1-Y1, and is a schematic diagram following Figure 5. Figure 20 is a cross-sectional view of Figure 18 taken along the line X2-X2, and is a schematic diagram following Figure 5.
[0126] The modified light-receiving and light-emitting package 1 shown in Figures 18 to 20 includes a second light-emitting element 71 and a second light-receiving element 81, in addition to the first light-emitting element 31 and the first light-receiving element 41.
[0127] The light-receiving package 1 shown in Figures 18 to 20 includes a first recess 21, a second recess 22, a third recess 23, and a fourth recess 24. Each of the recesses (21, 22, 23, 24) belongs to one of the multiple recesses 20.
[0128] The second light-emitting element 71 is installed within the third recess 23 with its light-emitting surface facing the opening of the third recess 23, i.e., the first surface 3a. The second light-emitting element 71 has a different peak emission wavelength than the first light-emitting element 31. Furthermore, the first light-receiving element 41 does not have any light-receiving sensitivity to the light emitted by the second light-emitting element 71.
[0129] The second light-receiving element 81 is installed within the fourth recess 24 with its light-receiving surface facing the opening of the fourth recess 24, i.e., the first surface 3a. The second light-receiving element 81 exhibits light-receiving sensitivity to the light emitted by the second light-emitting element 71, but does not exhibit light-receiving sensitivity to the light emitted by the first light-emitting element 31.
[0130] As shown in Figure 19, the second light-receiving element 81 is sealed within the fourth recess 24 by the third sealing portion 53. In this modified example, the second light-emitting element 71 is sealed within the third recess 23 by the fourth sealing portion 54.
[0131] The third sealing portion 53 is made of a material that is transparent to the light emitted by the second light-emitting element 71. If the third sealing portion 53 is also transparent to the light emitted by the first light-emitting element 31, it can be made of the same material as the first sealing portion 51.
[0132] The fourth sealing portion 54 is made of a material that is transparent to the light emitted by the second light-emitting element 71. The fourth sealing portion 54 may be made of the same material as the third sealing portion 53.
[0133] As shown in Figure 19, the third sealing portion 53 that seals the second light-receiving element 81 within the fourth recess 24 is formed so as not to reach the third recess 23. This provides the same effect as described above with reference to Figure 8.
[0134] On the other hand, as shown in Figure 20, the third sealing portion 53 that seals the second light-receiving element 81 within the fourth recess 24 may extend into the first recess 21. As described above, the second light-receiving element 81 does not originally show any light-receiving sensitivity to the light emitted by the first light-emitting element 31. Therefore, even if the light emitted by the first light-emitting element 31 travels through the sealing portions (52, 53) and is incident on the second light-receiving element 81, it does not affect the amount of light received by the second light-receiving element 81.
[0135] However, the third sealing portion 53 that seals the second light-receiving element 81 within the fourth recess 24 may be configured not to reach either the third recess 23 or the first recess 21.
[0136] In the modified examples shown in Figures 18 to 20, the light-receiving package 1 may be provided with a plurality of second light-emitting elements 71. Alternatively, as described above, it may be provided with a plurality of first light-emitting elements 31. Furthermore, this modified example can be appropriately combined with the embodiments and other modified examples described above.
[0137] [Alternative Embodiments] Alternative embodiments will be described below.
[0138] (1) In the above embodiment, as described above with reference to Figure 2, the base portion 3 is formed by bonding a first substrate 11 and a second substrate 12 in which through holes 14 are formed. However, the base portion 3 may be an integrated structure in which a plurality of recesses 20 are formed. In this case, the base portion 3 is integrally formed of a material that exhibits light-shielding properties against the light emitted by the first light-emitting element 31.
[0139] <2> In the above embodiment, the first light-receiving element 41 provided in the light-receiving package 1 shown in Figure 1 is configured to show light-receiving sensitivity to the light emitted by the first light-emitting element 31a, the first light-emitting element 31b, and the first light-emitting element 31c. However, if there is a separate light-receiving element outside the light-receiving package 1, the first light-receiving element 41 does not need to have light-receiving sensitivity to all of the light emitted by the first light-emitting element 31a, the first light-emitting element 31b, and the first light-emitting element 31c. For example, the first light-receiving element 41 may have light-receiving sensitivity to the light emitted by the first light-emitting element 31a and the first light-emitting element 31b, but not to the light emitted by the first light-emitting element 31c. In this case, a separate light-receiving element that has light-receiving sensitivity to the light emitted by the first light-emitting element 31c may be provided outside the light-receiving package 1.
[0140] <3> In the above embodiment, the first light-emitting element 31 was described as being sealed by the second sealing part 52, but the present invention also covers cases where the first light-emitting element 31 is installed in the first recess 21 without being sealed. The same applies to the second light-emitting element 71.
[0141] <4> In the above embodiment, a pad electrode 36 is formed on the light-emitting surface of the first light-emitting element 31, and the case in which this pad electrode 36 is connected to the first energizing part 32 by a wire 35 has been described. However, the present invention does not exclude the case in which the first light-emitting element 31 is flip-chip mounted on the first substrate 11 within the first recess 21. The same applies to the first light-receiving element 41, the second light-emitting element 71, and the second light-receiving element 81.
[0142] <5> If the main emission wavelength of the first light-emitting element 31 is in the infrared region, a material that exhibits light-shielding properties in the visible region may be mixed into the second sealing portion 52 that seals the first light-receiving element 41 for the purpose of cutting out ambient light. Alternatively, a visible light cut filter may be mounted on the light-receiving surface of the first light-receiving element 41. The same applies to the third sealing portion 53 that seals the second light-receiving element 81 and the light-receiving surface of the second light-receiving element 81.
[0143] <6> A material that exhibits diffusivity to the detected light L2 may be mixed into the second sealing portion 52 that seals the first light-receiving element 41. The same applies to the third sealing portion 53 that seals the second light-receiving element 81.
[0144] (7) The present invention is not limited to the embodiments described above, and includes various modifications. For example, the embodiments described above are described in detail for a better understanding of the present invention and are not necessarily limited to all configurations described. The scope of the present invention is indicated by the claims, and all modifications within the meaning and scope equivalent to the claims are intended to be included.
[0145] 1: Light-receiving package 3: Base part 3a: First surface of base part 3b: Second surface of base part 5: Object to be illuminated 11: First substrate 12: Second substrate 14: Through hole 16: Adhesive layer 17: Reflective member 20: Recess 21: First recess 22: Second recess 23: Third recess 24: Fourth recess 26: Excess recess 31, 31a, 31b, 31c: First light-emitting element 32: First energizing part for the first light-emitting element 33: Second energizing part for the first light-emitting element 34: Insulating part 35: Wire for the first light-emitting element 36: Pad electrode for the first light-emitting element 37, 38: Electrode terminals of the first light-emitting element 41: First light-receiving element 42: First energizing part for the first light-receiving element 43: Second energizing part for the first light-receiving element 44: Insulating part 45: Wire for the first light-receiving element 46: Pad electrode for the first light-receiving element 47, 48: Electrode terminals of the first light-receiving element 51: First sealing part 51a: Top surface of the first sealing part 52: Second sealing part 52a: Top surface of the second sealing part 53: Third sealing part 54: Fourth sealing part 61: Heat dissipation part 71: Second light-emitting element 81: Second light-receiving element 90: Light-receiving package for verification 91: Sealing part L1: First light L2: Detected light
Claims
1. A light-receiving package comprising: a base portion having a first surface and a second surface facing a first direction perpendicular to the first surface; a plurality of recesses formed on the first surface of the base portion at intervals and having a bottomed opening shape with the first surface side open; a first light-emitting element housed inside a first recess belonging to the plurality of recesses, with its light-emitting surface facing the opening of the first recess; a first light-receiving element housed inside a second recess belonging to the plurality of recesses but different from the first recess, with its light-receiving surface facing the opening of the second recess, and exhibiting light-receiving sensitivity to light emitted by the first light-emitting element; and a first sealing portion that seals the first light-receiving element within the second recess and is made of a material that exhibits light transmittance to light emitted by the first light-emitting element, wherein the inner wall of the first recess exhibits light-shielding properties to light emitted by the first light-emitting element, and the first sealing portion does not reach the inside of the first recess when viewed in the first direction.
2. The light-receiving package according to claim 1, wherein the base portion comprises a first substrate, a second substrate having a plurality of discretely spaced through holes, and an adhesive layer for bonding the first substrate and the second substrate, the plurality of recesses are composed of the through holes and a portion of the first substrate located at the bottom of the through holes, and the adhesive layer is made of a material that exhibits light-shielding properties against light emitted by the first light-emitting element.
3. The light-emitting and light-receiving package according to claim 1 or 2, wherein the first light-emitting element is positioned, when viewed in the first direction, at a location offset from the center of the first recess toward the first light-receiving element.
4. The light-receiving package according to claim 1 or 2, wherein the first recess has a reflective member on its inner wall made of a material that exhibits reflectivity to light emitted by the first light-emitting element.
5. The light-receiving package according to claim 4, wherein the opening area of the first recess at a position close to the second surface is smaller than the opening area at a position close to the first surface.
6. The light-receiving package according to claim 1 or 2, wherein the uppermost surface of the first sealing portion in the first direction is located inside the second recess.
7. The light-receiving package according to claim 1 or 2, comprising a second sealing portion made of a material that is transparent to light emitted by the first light-emitting element and seals the first light-emitting element within the first recess, wherein the second sealing portion does not reach the inside of the second recess when viewed in the first direction.
8. The light-receiving and light-emitting package according to claim 1 or 2, wherein a first current-carrying portion made of a conductive material is provided at a portion of the base portion, and a wire connecting the first current-carrying portion and a pad electrode formed on the light-emitting surface side of the first light-emitting element, the wire extending in a direction away from the first light-receiving element.
9. The light-receiving package according to claim 8, wherein the first light-emitting element has a linear electrode formed on the light-emitting surface side, and the wire extends along the linear electrode such that it substantially overlaps the linear electrode when viewed in the first direction.
10. The light-receiving package according to claim 1 or 2, wherein a plurality of first light-emitting elements having different emission wavelengths are housed inside the first recess.
11. The light-receiving package according to claim 1 or 2, comprising a plurality of first recesses, wherein at least two of the plurality of first light-emitting elements housed in each of the plurality of first recesses have different peak emission wavelengths.
12. The light-receiving package according to claim 11, wherein the first light-receiving element has a pad electrode formed on the light-receiving surface side, the plurality of recesses are arranged along multiple rows and multiple columns when viewed in the first direction, the second recess is positioned at a location corresponding to the corner of the plurality of recesses when viewed in the first direction, and the pad electrode of the first light-receiving element is formed on the light-receiving surface side at a position far from the first light-emitting element.
13. The light-receiving and light-receiving package according to claim 11, comprising: a third recess and a fourth recess belonging to the plurality of recesses; a second light-emitting element housed inside the third recess with its light-emitting surface facing the opening of the third recess, and having a peak emission wavelength different from that of the first light-emitting element; a second light-receiving element housed inside the fourth recess with its light-receiving surface facing the opening of the fourth recess; and a third sealing portion that seals the second light-receiving element within the fourth recess, wherein the first light-receiving element does not exhibit light-receiving sensitivity to light emitted by the second light-emitting element, the second light-receiving element exhibits light-receiving sensitivity to light emitted by the second light-emitting element, and the third sealing portion does not reach the inside of the third recess when viewed in the first direction.
14. The light-receiving package according to claim 11, wherein, when viewed in the first direction, at least one of the plurality of recesses has a different shape from the other recesses, and when rotated in a direction parallel to the first surface with respect to the center of the first surface, the shape formed by the plurality of recesses is rotationally asymmetric.
15. The light-receiving package according to claim 8, further comprising: a second energizing portion formed in the first recess on the surface of the first light-emitting element opposite to the light-emitting surface of the first light-emitting element; and an insulating portion disposed in the first recess, when viewed in the first direction, between the first energizing portion and the second energizing portion, wherein the first energizing portion and the second energizing portion are each connected to the same side surface of the base portion.
16. The light-receiving package according to claim 15, wherein the second energizing portion reaches the second surface of the base portion.