JP6279414B2 - Emitter / receiver module - Google Patents

Description

  The present invention relates to a light projecting / receiving module.

  A light emitting / receiving module that includes a light emitting element and a light receiving element, projects light emitted from the light emitting element onto an object, and receives reflected light from the object by the light receiving element is known (for example, see Patent Document 1). ). The light projecting / receiving module disclosed in Patent Document 1 includes a substrate, a light emitting element, a light receiving element, and a resin package that covers the light emitting element and the light receiving element. The resin package is formed on the substrate by a technique such as a transfer mold method.

JP 2008-258298 A

  It is an object of the present invention to provide a light projecting / receiving module capable of realizing optical characteristics and reducing the size with a simple configuration.

  As a result of research, the present inventors have newly found the following facts.

  In the light projecting / receiving module, a protection member made of a material that transmits light emitted from the light emitting element and reflected light from the object is required to protect the light receiving element or improve optical characteristics. When a resin package formed by a transfer molding method is employed as a protective member as in the light emitting / receiving module disclosed in Patent Document 1, bubbles may be mixed into the resin when molding the resin. And optical characteristics may be deteriorated. In addition, when the resin is molded, the light receiving element or the light emitting element may be physically damaged. In this case, the optical characteristics of the light projecting / receiving module are not secured.

  In order to ensure optical characteristics and to reduce the size of the module with a simple configuration, it is conceivable to employ a plate-like member (hereinafter referred to as a protective plate) as the protective member. In this case, the protection plate is disposed so as to close the opening of the substrate on which the light emitting element and the light receiving element are disposed. The opening is necessary to project light emitted from the light emitting element onto the object and to allow reflected light from the object to enter the light receiving element.

  However, when the opening of the substrate is blocked by the protective plate, the gas present in the space in the light emitting / receiving module (substrate) is compressed, the internal pressure of the light emitting / receiving module increases, and the protective plate is disposed at a desired position. Becomes difficult. Therefore, the present inventors have further conducted intensive research on a configuration in which the protective plate can be easily arranged at a desired position, and have come to correspond to the present invention.

  The present invention is a light projecting / receiving module that includes a light emitting element and a light receiving element, projects light emitted from the light emitting element onto an object, and receives reflected light from the object by the light receiving element, and is a first module facing each other. A first substrate having a first surface and a second surface; a second substrate having a third surface and a fourth surface facing each other; and the third substrate being disposed so as to face the second surface; The structure includes a protective plate that is disposed on the second substrate so as to face the fourth surface, and that has a protective plate that transmits light emitted from the light emitting element and light from the object. A light emitting element is positioned, and a space portion configured to be defined by the first substrate and the second substrate, and a light receiving element is positioned, and are configured to be recessed from the fourth surface side of the second substrate. And a communication path that communicates the space portion with the outside of the structure. The child is positioned on a virtual axis extending in a direction in which the first surface and the second surface face each other, the space portion is positioned on one of the first substrate and the second substrate, and the light emitting element Are arranged on the first substrate, and a light reflecting surface that reflects and guides the light emitted from the light emitting element to the second substrate side, and the second substrate has A plurality of through holes having one end opened in a region facing the light reflecting surface on the third surface and the other end opened in the fourth surface and extending in a direction in which the third surface and the fourth surface face each other are virtual axes. The protection plate is disposed on the second substrate so as to at least close the recess and the plurality of through holes.

  In the present invention, the light emitting element is located in a space portion formed in the structure, and the light receiving element is located in a recess formed in the structure. The protection plate is disposed on the second substrate so as to at least close the recess and the plurality of through holes. In the protective plate, the light emitted from the light emitting element and the light from the object are transmitted. The light emitted from the light emitting element is reflected by the light reflecting surface and travels toward the second substrate side. The light reflected by the light reflecting surface passes through the protective plate through the plurality of through holes formed in the second substrate. Thereby, light is projected from the light projecting / receiving module to the object. The reflected light from the object passes through the protective plate and enters the light receiving element. Therefore, in the light projecting / receiving module according to the present invention, the optical characteristics can be ensured and miniaturized with a simple configuration.

  In the present invention, a communication path that communicates the space portion with the outside of the structure is formed in the structure. The plurality of through-holes closed by the protective plate communicate with the space portion. For this reason, when the plurality of through holes are closed by the protective plate, the gas present in the light projecting / receiving module (space portion) passes through the communication path and is discharged to the outside of the structure. Therefore, an increase in the internal pressure of the light projecting / receiving module is suppressed, and the protective plate can be arranged at a desired position.

  The communication path may be formed between the second surface of the first substrate and the third surface of the second substrate so as to extend between the space portion and the outer surface of the structure. In this case, the formation of the communication path can be easily realized.

  At least one of the second surface of the first substrate and the third surface of the second substrate has an electric insulating film arrangement region where an electric insulating film is arranged, and an electric insulating film non-arrangement region where no electric insulating film is arranged And the electric insulating film non-arrangement region may constitute a communication path. In this case, the formation of the communication path can be realized easily and easily.

  At least one of the second surface of the first substrate and the third surface of the second substrate has a conductor film placement region where the conductor film is placed and a conductor film non-placement region where the conductor film is not placed. In addition, the conductor film non-arrangement region may constitute a communication path. In this case, the formation of the communication path can be realized easily and easily.

  A groove is formed on at least one of the second surface side of the first substrate and the third surface side of the second substrate, and the groove may constitute a communication path. In this case, the formation of the communication path can be realized easily and easily.

  The space is defined by a recess formed in the first substrate and a second substrate, and the recess formed in the first substrate serves as an element arrangement surface as a surface of the recess, And a light reflection surface located outside the element arrangement surface. In this case, a light emitting / receiving module in which the light emitting element is arranged on the first substrate side is realized.

  The space is defined by a recess formed in the first substrate and a second substrate, and the second substrate includes an element arrangement surface on the third surface side, and is formed on the first substrate. The concave portion may include a light reflecting surface located outside the element arrangement surface as viewed from the direction in which the third surface and the fourth surface face each other as the surface of the concave portion. In this case, a light emitting / receiving module in which the light emitting element is arranged on the second substrate side is realized.

  In the space portion, a light reflecting surface that is located on each of the first substrate and the second substrate and is opposite to each other in a direction in which the second surface and the third surface face each other, and reflects light emitted from the light emitting element. May be facing. In this case, the light emitted from the light emitting element can be efficiently guided to the plurality of through holes.

ADVANTAGE OF THE INVENTION According to this invention, the light projection / reception module which can implement | achieve ensuring of an optical characteristic and size reduction with a simple structure can be provided.

It is a perspective view which shows the light projection / reception module which concerns on embodiment of this invention. It is a disassembled perspective view which shows the light projection / reception module which concerns on this embodiment. It is a disassembled perspective view which shows the light projection / reception module which concerns on this embodiment. It is a figure for demonstrating the cross-sectional structure along the IV-IV line | wire of FIG. It is a figure for demonstrating the cross-sectional structure along the VV line of FIG. It is a figure for demonstrating the cross-sectional structure along the VI-VI line of FIG. It is the elements on larger scale of the light projection / reception module shown by FIG. It is a figure for demonstrating the effect of the light projection / reception module which concerns on this embodiment. It is a figure for demonstrating the effect of the light projection / reception module which concerns on this embodiment. It is a perspective view which shows the 2nd board | substrate with which the light projection / reception module which concerns on the modification of this embodiment is provided. It is a figure for demonstrating the cross-sectional structure of the light projection / reception module which concerns on the modification of this embodiment. It is a perspective view which shows the light projection / reception module which concerns on the modification of this embodiment. It is a figure for demonstrating the cross-sectional structure of the light projection / reception module which concerns on the modification of this embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

  With reference to FIGS. 1-7, the structure of the light projection / reception module M1 which concerns on this embodiment is demonstrated. FIG. 1 is a perspective view showing a light projecting / receiving module according to an embodiment of the present invention. FIG. 2 is an exploded perspective view showing the light projecting / receiving module according to the present embodiment. FIG. 3 is an exploded perspective view showing the light projecting / receiving module according to the present embodiment. FIG. 4 is a diagram for explaining a cross-sectional configuration along the line IV-IV in FIG. 1. FIG. 5 is a diagram for explaining a cross-sectional configuration along the line V-V in FIG. 1. FIG. 6 is a diagram for explaining a cross-sectional configuration along the line VI-VI in FIG. 1. FIG. 7 is a partially enlarged view of the light projecting / receiving module shown in FIG.

  The light projecting / receiving module M1 includes a light emitting element EE, a light receiving element RE, and a structure 1. The light projecting / receiving module M1 projects the light emitted from the light emitting element EE onto the object, and the reflected light from the object is received by the light receiving element RE. The structure 1 includes a first substrate 10, a second substrate 20, and a protection plate 30. For example, an LED (Light Emitting Diode) is used for the light emitting element EE. As the light receiving element RE, for example, a semiconductor light receiving element or the like is used.

  The first substrate 10 has a first surface 10a and a second surface 10b facing each other. The first surface 10 a and the second surface 10 b are opposed to each other in the thickness direction of the first substrate 10. The first substrate 10 has a rectangular shape (in this embodiment, a square shape) in plan view. When the 1st board | substrate 10 is square shape, the length of the one side of the 1st board | substrate 10 is 10 mm, for example. A first recess 11 is formed in the first substrate 10. In this embodiment, the 1st recessed part 11 is comprised by the hollow formed in the 1st board | substrate 10 from the 2nd surface 10b side, and the 1st metal film 12 arrange | positioned at the surface of the hollow. That is, the first substrate 10 has the first metal film 12. The first substrate 10 is configured by a printed circuit board such as a PWB (Printed Wiring Board), for example.

  The first opening 11a of the first recess 11 has a substantially circular shape (in the present embodiment, a perfect circle shape). The first recess 11 is defined by a first bottom surface 11b and a first inner side surface 11c. The first bottom surface 11b has a substantially circular shape (in the present embodiment, a perfect circular shape). The center of the first opening 11a and the center of the first bottom surface 11b substantially coincide with each other in plan view. The diameter of the first bottom surface 11b is set smaller than the diameter of the first opening 11a, and the first inner side surface 11c is inclined in a tapered shape. That is, the space formed by the first recess 11 has an inverted truncated cone shape.

  The first metal film 12 has a first portion 12a and a second portion 12b that are positioned so as to be separated from each other. The first portion 12a and the second portion 12b are electrically insulated from each other. The surfaces of the first portion 12a and the second portion 12b constitute a first bottom surface 11b and a first inner side surface 11c. The second portion 12b extends in the radial direction of the first bottom surface 11b so as to reach the second surface 10b from the central portion of the first bottom surface 11b. The second portion 12b has a substantially strip shape. The first metal film 12 is made of, for example, gold. The first metal film 12 is formed on the first substrate 10 by, for example, a plating method.

The first bottom surface 11b includes a region 11b ₁ located in the center of the first bottom surface 11b, a region 11b ₂ positioned outside the region 11b ₁ so as to surround the region 11b _1, a. The region 11b ₁ is configured by the surface of the first portion 12a. In the region 11b ₁ , the light emitting element EE is arranged. That is, the region 11b ₁ functions as an element arrangement surface on which the light emitting element EE is arranged, and the light emitting element EE is located in the first recess 11. The light emitting element EE is arranged so that the light emitting surface faces the first opening 11a side of the first recess 11. Emitting element EE is the first portion 12a electrically connected to constitute the region 11b _1. The light emitting element EE is also electrically connected to the second portion 12b through a bonding wire.

  On the second surface 10 b of the first substrate 10, a plurality of land-shaped electrode pads 17 are arranged along each side. Therefore, the second surface 10b has a region where the plurality of electrode pads 17 are disposed and a region where the plurality of electrode pads 17 are not disposed. The plurality of electrode pads 17 are separated from each other on the second surface 10b. At least one electrode pad 17 among the plurality of electrode pads 17 is electrically connected to the first portion 12a. Of the plurality of electrode pads 17, at least one electrode pad 17 except for the electrode pad 17 electrically connected to the first portion 12a is electrically connected to the second portion 12b. The plurality of electrode pads 17 are made of a conductive material (for example, gold). The plurality of electrode pads 17 function as a conductor film. The thickness of the electrode pad 17 is, for example, about 50 μm.

  The plurality of electrode pads 17 function as a conductor film. Accordingly, the region where the plurality of electrode pads 17 are arranged on the second surface 10b functions as a conductor film arrangement region. The area | region where the some electrode pad 17 in the 2nd surface 10b is not arrange | positioned functions as a conductor film non-arrangement area | region. The number of conductor film arrangement regions corresponds to the number of electrode pads 17. Further, the conductor film arrangement regions are located so as to be separated from each other. That is, a part of the conductor film non-arrangement region is located between the conductor film arrangement regions. In the present embodiment, the second surface 10b has a plurality of conductor film arrangement regions and one conductor film non-arrangement region.

  A plurality of electrical insulating films 19 are arranged on the second surface 10b of the first substrate 10 so as to correspond to the respective sides. In the present embodiment, four electrical insulating films 19 are disposed on the second surface 10b. The electrical insulating films 19 are separated from each other on the second surface 10b. The electric insulating film 19 is made of an electric insulating material. As the electrical insulating film 19, for example, a resist film is used. The thickness of the electrical insulating film 19 is, for example, about 50 μm.

  The inner end portion of each electrical insulating film 19 is located in the vicinity of the first opening 11a so as to be along the first opening 11a. The outer end portion of each electrical insulating film 19 is located at the outer edge of the second surface 10b constituting the side so as to be along the corresponding side of the second surface 10b. As described above, since the electrical insulating films 19 are separated from each other, there is a region where the electrical insulating film 19 is not disposed between two adjacent electrical insulating films 19. In the region where the electrical insulating film 19 is not disposed, the second surface 10b is exposed.

  The region where the plurality of electrode pads 17 are not disposed on the second surface 10b includes a plurality of regions where the electrical insulating film 19 is disposed and a plurality of regions where the electrical insulating film 19 is not disposed. . The region where the electric insulating film 19 is disposed is an electric insulating film arrangement region, and the region where the electric insulating film 19 is not disposed is an electric insulating film non-arrangement region. That is, the second surface 10b has an electric insulating film arrangement region and an electric insulating film non-arrangement region. In the present embodiment, the second surface 10b has four electric insulating film arrangement regions and electric insulating film non-arrangement regions, respectively.

  Each region where the electrical insulating film 19 is not disposed is located between two adjacent electrical insulating films 19 so as to extend from the first opening 11a to the side (outer edge) of the second surface 10b. In the present embodiment, among the four sides of the second surface 10b, each region where the electrical insulating film 19 is not arranged reaches two opposite sides. Each region where the electrical insulating film 19 is not disposed has a first portion extending radially from the first opening 11a and a side of the second surface 10b from the first opening 11a when viewed from a direction orthogonal to the second surface 10b. And a second portion extending in a direction orthogonal to the side. In each region where the electrical insulating film 19 is not disposed, a groove is formed by the two electrical insulating films 19 located on both sides of the region as viewed from the direction orthogonal to the second surface 10b. The depth of this groove corresponds to the thickness of the electrical insulating film 19.

  In the first substrate 10, a plurality of through wirings 16 are arranged corresponding to the plurality of electrode pads 17, respectively. That is, the plurality of through wirings 16 are arranged so as to be arranged along each side of the second surface 10b when viewed from a direction orthogonal to the second surface 10b. Each through wiring 16 is provided so as to penetrate between the second surface 10 b and the first surface 10 a of the first substrate 10 at the position of the corresponding electrode pad 17. The corresponding electrode pad 17 and the through wiring 16 are physically and electrically connected. The number of electrode pads 17 and the number of through wirings 16 are the same. The through wiring 16 is made of a conductive material (for example, copper).

  On the first surface 10 a of the first substrate 10, a plurality of land-like external electrodes 15 are arranged corresponding to the plurality of through wirings 16 (a plurality of electrode pads 17). That is, a plurality of external electrodes 15 are arranged along the sides on the second surface 10b. Each external electrode 15 is provided so as to cover the through wiring 16 at the position of the corresponding through wiring 16. The corresponding external electrode 15 and the through wiring 16 are physically and electrically connected. Therefore, when viewed from the direction orthogonal to the second surface 10 b (first surface 10 a), the electrode pad 17 and the external electrode 15 at the same position are electrically connected through the through wiring 16. The number of external electrodes 15 and the number of through wirings 16 are the same.

  The light emitting element EE has a pair of terminal portions for applying a voltage. One terminal portion passes through the second portion 12b of the first metal film 12, the electrode pad 17 to which the second portion 12b is electrically connected, and the through wiring 16 to which the electrode pad 17 is electrically connected. The through wiring 16 is electrically connected to the external electrode 15 to which the through wiring 16 is electrically connected. The other terminal portion passes through the first portion 12a of the first metal film 12, the electrode pad 17 to which the first portion 12a is electrically connected, and the through wire 16 to which the electrode pad 17 is electrically connected. 16 is electrically connected to the external electrode 15 electrically connected thereto.

  The second substrate 20 has a third surface 20a and a fourth surface 20b facing each other. The third surface 20a and the fourth surface 20b oppose each other in the thickness direction of the second substrate 20. The second substrate 20 is disposed on the first substrate 10 such that the third surface 20a and the second surface 10b of the first substrate 10 face each other. The second substrate 20 has a rectangular shape (in this embodiment, a square shape) in plan view. When the 2nd board | substrate 20 is square shape, the length of the one side of the 2nd board | substrate 20 is 10 mm, for example. The second substrate 20 is made of a member that has a light blocking property with respect to light emitted from the light emitting element EE. The second substrate 20 is configured by a printed circuit board such as a PWB (Printed Wiring Board), for example. In the present embodiment, the planar shape and the planar size of the second substrate 20 are the same as the planar shape and the planar size of the first substrate 10.

  A second recess 21 is formed on the second substrate 20 on the fourth surface 20b side. That is, the second recess 21 is configured to be recessed from the fourth surface 20 b side of the second substrate 20. The second opening 21a of the second recess 21 has a substantially rectangular shape. The bottom surface of the second recess 21 has a substantially rectangular shape. The space formed by the second recess 21 has a rectangular parallelepiped shape. A third metal film 23 is disposed on the bottom surface of the second recess 21. The third metal film 23 is made of, for example, gold. The thickness of the third metal film 23 is, for example, about 50 μm.

  On the third surface 20a of the second substrate 20, a plurality of land-like electrode pads 18 are arranged along each side. Therefore, the third surface 20a has a region where the plurality of electrode pads 18 are disposed and a region where the plurality of electrode pads 18 are not disposed. The plurality of electrode pads 18 are separated from each other on the third surface 20a. The plurality of electrode pads 18 are made of a conductive material (for example, gold). The plurality of electrode pads 18 function as a conductor film. The thickness of the electrode pad 18 is, for example, about 50 μm.

  Each electrode pad 17 and each electrode pad 18 are in positions facing each other in a state where the first substrate 10 and the second substrate 20 are disposed facing each other. That is, each electrode pad 17 and each electrode pad 18 are at the same position when viewed from the direction orthogonal to the first surface 10a (fourth surface 20b). The electrode pad 17 and the electrode pad 18 at the same position are electrically connected by a bump conductor 27. The first substrate 10 and the second substrate 20 are integrated in a state where the first substrate 10 and the second substrate 20 are overlapped by the bump conductor 27. The 1st board | substrate 10 and the 2nd board | substrate 20 are arrange | positioned in the state overlaid so that the position of the four sides which comprise the outer edge of each board | substrate 10 and 20 may correspond.

  Each of the plurality of electrode pads 17 and electrode pad 18 includes a so-called dummy electrode that does not contribute to electrical connection. The electrode pads 17 and electrode pads 18 that function as dummy electrodes are physically connected by the bump conductors 27, whereby the connection strength between the first substrate 10 and the second substrate 20 is improved. The external electrode 15 electrically connected to the electrode pad 17 that functions as a dummy electrode also functions as a dummy electrode. The external electrode 15 functioning as a dummy electrode contributes to improving the mounting strength of the light projecting / receiving module M1 when the light projecting / receiving module M1 is mounted on another electronic device (circuit board or electronic component). The dummy electrode is not always necessary.

  A plurality of internal wirings 26 are arranged on the second substrate 20 corresponding to the plurality of electrode pads 18, respectively. That is, the plurality of internal wirings 26 are arranged so as to be arranged along each side of the third surface 20a when viewed from a direction orthogonal to the third surface 20a. Each internal wiring 26 is provided at the position of the corresponding electrode pad 18 so as to extend in the second substrate 20 in the direction in which the third surface 20a and the fourth surface 20b face each other. The corresponding electrode pad 18 and the internal wiring 26 are physically and electrically connected. The number of electrode pads 18 and the number of internal wirings 26 are the same. The internal wiring 26 is made of a conductive material (for example, copper).

  On the second substrate 20, a plurality of fourth metal films 25 are arranged corresponding to the plurality of internal wirings 26. Each fourth metal film 25 has one end electrically connected to the corresponding internal wiring 26 and the other end exposed at the bottom surface of the second recess 21. Each fourth metal film 25 is provided so as to extend in the second substrate 20 in a plane parallel to the third surface 20a (fourth surface 20b). The plurality of fourth metal films 25 are electrically insulated from each other in the second substrate 20. The number of fourth metal films 25 and the number of internal wirings 26 are the same. The fourth metal film 25 is made of, for example, gold. The thickness of the fourth metal film 25 is, for example, about 50 μm.

  The light receiving element RE is disposed on the third metal film 23. That is, the light receiving element RE is located in the second recess 21. The light receiving element RE is arranged so that the light incident surface faces the second opening 21 a side of the second recess 21. The light receiving element RE, together with the light emitting element EE, is located on a virtual axis L extending in a direction in which the first surface 10a and the second surface 10b face each other. In the present embodiment, the center of the first bottom surface 11b and the center of the second bottom surface 21b are also located on the virtual axis L.

  The input / output terminal of the light receiving element RE is electrically connected to the corresponding fourth metal film 25 through a bonding wire. That is, the input / output terminals of the light receiving element RE are the corresponding fourth metal film 25, the internal wiring 26 electrically connected to the fourth metal film 25, and the electrode electrically connected to the internal wiring 26. Pad 18, bump conductor 27 electrically connected to the electrode pad 18, electrode pad 17 electrically connected to the bump conductor 27, and through wiring 16 to which the electrode pad 17 is electrically connected The through wiring 16 is electrically connected to the external electrode 15 electrically connected thereto.

A plurality of through holes 24 are formed in the second substrate 20. In the present embodiment, two through holes 24 are formed in the second substrate 20. The through hole 24 extends in a direction in which the third surface 20a and the fourth surface 20b face each other. One end of each through-hole 24, in the third surface 20a, is open in a region opposed to a region 11b ₂ of the first bottom surface 11b and the first inner surface 11c. The other end of each through hole 24 opens to the fourth surface 20b.

  The two through holes 24 are formed at positions that are rotationally symmetric with respect to the virtual axis L. That is, one end of each through hole 24 is positioned rotationally symmetric with respect to the virtual axis L on the third surface 20a, and the other end of each through hole 24 rotates with respect to the virtual axis L on the fourth surface 20b. Located symmetrically. The opening shape at one end and the other end of each through hole 24 is substantially rectangular. The light receiving element RE (second recess 21) is located between the two through holes 24 when viewed from the direction orthogonal to the fourth surface 20b.

  In the third surface 20 a, a second metal film 22 is disposed in a region located between the two through holes 24. In the structure 1, a space 40 defined by the first recess 11 of the first substrate 10 and the second substrate 20 is formed. The second metal film 22 is positioned so as to be exposed to the space 40. The first metal film 12 is also located so as to be exposed to the space 40. That is, the space 40 is configured to be surrounded by the first metal film 12 and the second metal film 22. The first metal film 12 and the second metal film 22 face each other in the direction in which the second surface 10b and the third surface 20a face each other with the space portion 40 interposed therebetween. The second metal film 22 has a shape having a longitudinal direction and a lateral direction. The longitudinal direction of the second metal film 22 is a direction along the longitudinal direction of the opening shape of the through hole 24. The second metal film 22 is made of, for example, gold. The second metal film 22 is formed on the second substrate 20 by, for example, a plating method.

  The plurality of electrode pads 18 function as a conductor film. Accordingly, the region where the plurality of electrode pads 18 are arranged on the third surface 20a functions as a conductor film arrangement region. The area | region where the some electrode pad 18 in the 3rd surface 20a is not arrange | positioned functions as a conductor film non-arrangement area | region. The number of conductor film arrangement regions corresponds to the number of electrode pads 18. Also on the third surface 20a, the conductor film arrangement regions are positioned so as to be separated from each other. That is, part of the conductor film non-arrangement region is located between the conductor film arrangement regions also on the third surface 20a. In the present embodiment, the third surface 20a has a plurality of conductor film arrangement regions and one conductor film non-arrangement region.

  A plurality of electrical insulating films 28 are arranged on the third surface 20a of the second substrate 20 so as to correspond to the respective sides. In the present embodiment, the four electrical insulating films 28 are arranged in a region excluding a region located between the two through holes 24 (a region where the second metal film 22 is disposed) on the third surface 20a. Yes. The electric insulating films 28 are separated from each other on the third surface 20a. The electric insulating film 28 is made of an electric insulating material, like the electric insulating film 19. As the electrical insulating film 28, for example, a resist film is used. The thickness of the electrical insulating film 28 is also about 50 μm, for example.

  The outer end portion of each electrical insulating film 28 is located at the outer edge of the third surface 20a constituting the side so as to be along the corresponding side of the third surface 20a. As described above, since the electrical insulating films 28 are separated from each other, there is a region where the electrical insulating film 28 is not disposed between two adjacent electrical insulating films 28. In the region where the electrical insulating film 28 is not disposed, the third surface 20a is exposed.

  The region where the plurality of electrode pads 18 are not disposed on the third surface 20a includes a plurality of regions where the electrical insulating film 28 is disposed and a plurality of regions where the electrical insulating film 28 is not disposed. . The region where the electrical insulation film 28 is disposed is an electrical insulation film placement region, and the region where the electrical insulation film 28 is not disposed is a region other than the region where the second metal film 22 is disposed. It is a placement area. That is, the third surface 20a has an electric insulating film arrangement region and an electric insulating film non-arrangement region except for the region where the second metal film 22 is arranged. In the present embodiment, the third surface 20a has four electric insulating film arrangement regions and electric insulating film non-arrangement regions, respectively.

  Each region where the electrical insulating film 28 is not disposed is located between the two electrical insulating films 28 adjacent to each other so as to extend from the through hole 24 to the side (outer edge) of the third surface 20a. In the present embodiment, among the four sides of the third surface 20a, each region where the electrical insulating film 28 is not arranged reaches two opposite sides. Each side to which each region where the electrical insulating film 28 is not disposed and each side to which the region where the electrical insulating film 19 is not disposed are viewed from a direction orthogonal to the first surface 10a (fourth surface 20b). In the same position.

  Each region where the electrical insulating film 28 is not disposed extends in a direction orthogonal to the side from the through hole 24 toward the side of the third surface 20a when viewed from the direction orthogonal to the third surface 20a. Each region where the electrical insulating film 28 is not disposed is the same position as the above-described second portion of the region where the electrical insulating film 19 is not disposed when viewed from the direction orthogonal to the first surface 10a (fourth surface 20b). It is in. In each region where the electrical insulating film 28 is not disposed, a groove is formed by the two electrical insulating films 28 located on both sides of the region as viewed from the direction orthogonal to the third surface 20a. The depth of this groove corresponds to the thickness of the electrical insulating film 28.

  The protection plate 30 is disposed on the second substrate so as to face the fourth surface 20b. The protection plate 30 is disposed on the second substrate 20 so as to close the second recess 21 and each through hole 24. The protection plate 30 is fixed to the second substrate 20 with an optical adhesive or the like. The protection plate 30 protects the second substrate 20 and improves the sealing performance of the light projecting / receiving module M1. The protection plate 30 is composed of a member through which light emitted from the light emitting element EE and light from the object are transmitted. The protection plate 30 is made of, for example, glass or resin. The protection plate 30 may function as an optical component such as a lens.

  The protection plate 30 has a rectangular shape (in this embodiment, a square shape) in plan view. When the protection plate 30 is square, the length of one side of the protection plate 30 is, for example, 10 mm. In the present embodiment, the planar shape and the planar size of the second substrate 20 are the same as the planar shape and the planar size of the first substrate 10 and the second substrate 20. The protection plate 30 is arranged on the second substrate 20 in a state where the four sides constituting the outer edge of the protection plate 30 are overlapped so that the positions of the four sides constituting the outer edge of the second substrate 20 coincide with each other. . Thereby, the structure 1 in which the first substrate 10, the second substrate 20, and the protection plate 30 are laminated has a rectangular parallelepiped shape.

  In the structure 1, the above-described space portion 40 and a communication path 41 that communicates the space portion 40 with the outside of the structure body 1 are formed. In the present embodiment, the communication path 41 is configured by the above-described electric insulating film non-arrangement region. That is, the communication path 41 includes a region where the electrical insulating film 19 is not disposed on the second surface 10b and a region where the electrical insulating film 28 is not disposed on the third surface 20a. The region where the electrical insulating films 19 and 28 are not disposed is in the same position as viewed from the direction orthogonal to the first surface 10a (fourth surface 20b), and the region where the electrical insulating films 19 and 28 are not disposed. As described above, the groove is formed. Therefore, a region (groove) where the electrical insulating films 19 and 28 are not disposed forms a space where one end communicates with the space portion 40 and the other end communicates with the outside of the structure 1. This space functions as the communication path 41. The communication path 41 constituted by the electric insulating film non-arrangement region is formed between the second surface 10b and the third surface 20a so as to extend between the space 40 and the outer surface of the structure 1. ing.

  In the present embodiment, the communication path 41 is also configured by the above-described conductor film non-arrangement region. That is, the communication path 41 includes a region where the electrode pad 17 is not disposed on the second surface 10b and a region where the electrode pad 18 is not disposed on the third surface 20a. A gap corresponding to the thickness of the bump conductor 27 is formed in a region where the electrode pads 17 and 18 are not disposed. This gap functions as the communication path 41. The communication path 41 constituted by the conductor film non-arrangement region is also formed between the second surface 10b and the third surface 20a so as to extend between the space 40 and the outer surface of the structure 1. Yes.

  Here, with reference to FIG.8 and FIG.9, the effect of the light projection / reception module M1 which concerns on this embodiment is demonstrated. FIG. 8 is a diagram for explaining the operational effects of the light projecting / receiving module according to the present embodiment. FIG. 9 is a diagram for explaining the function and effect of the light projecting / receiving module according to the present embodiment.

  As shown in FIG. 8, in this embodiment, when the light R1 is emitted from the light emitting element EE, the emitted light R1 is transmitted between the first metal film 12 and the second metal film 22 in the space portion 40. It is reflected and guided to each through hole 24. The surfaces of the first metal film 12 and the second metal film 22 function as light reflecting surfaces. In particular, the surface of the portion constituting the first inner surface 11c in the first metal film 12 functions as a light reflecting surface that reflects and guides the light emitted from the light emitting element EE to the second substrate 20 side.

  The portion constituting the first inner side surface 11c in the first metal film 12 is in a position overlapping with each through hole 24 when viewed from the direction orthogonal to the first surface 10a (fourth surface 20b). Therefore, the light reflected by the surface of the part which comprises the 1st inner surface 11c in the 1st metal film 12 is mainly guide | induced to each through-hole 24. FIG. The light guided to each through hole 24 passes through the protection plate 30 and is emitted from the light projecting / receiving module M1. The light emitted from the light projecting / receiving module M1 is projected onto the object OBJ. The reflected light R2 from the object OBJ passes through the protection plate 30 and enters the light receiving element RE. The reflected light R2 incident on the light receiving element RE is received by the light receiving element RE and converted into an electrical signal.

  As described above, in the present embodiment, the light emitting element EE is located in the space portion 40 formed in the structure 1, and the light receiving element RE is located in the second recess 21 formed in the structure 1. . The protection plate 30 is disposed on the second substrate 20 so as to at least close the second recess 21 and each through hole 24. In the protection plate 30, the light emitted from the light emitting element EE and the light from the object OBJ are transmitted. The light emitted from the light emitting element EE is reflected by the light reflecting surface constituted by the surfaces of the first metal film 12 and the second metal film 22 and travels toward the second substrate 20 side. The light reflected by the light reflecting surface passes through the protective plate 30 through each through hole 24 formed in the second substrate 20. As a result, light is projected from the light projecting / receiving module M1 onto the object OBJ. The reflected light from the object OBJ passes through the protective plate 30 and enters the light receiving element RE. Therefore, in the light projecting / receiving module M1, securing of optical characteristics and miniaturization can be realized with a simple configuration.

  As shown in FIG. 9, in the present embodiment, a communication path 41 that connects the space 40 to the outside of the structure 1 is formed in the structure 1. Each through hole 24 closed by the protection plate 30 communicates with the space 40. For this reason, when the through holes 24 are closed by the protective plate 30, the gas existing in the space 40 of the light projecting / receiving module M1 passes through the communication passage 41 as shown by the arrow A in FIG. , And discharged to the outside of the structure 1. Therefore, an increase in the internal pressure of the light projecting / receiving module M1 is suppressed, and the protective plate 30 can be disposed at a desired position.

  In the light projecting / receiving module M1, the second surface 10b of the first substrate 10 and the third surface 20a of the second substrate 20 are such that the communication path 41 extends between the space 40 and the outer surface of the structure 1. Is formed between. Thereby, formation of the communicating path 41 is easily realizable.

  In the light emitting / receiving module M1, the second surface 10b of the first substrate 10 and the third surface 20a of the second substrate 20 are provided with an electric insulating film arrangement region in which the electric insulating film 19 is arranged, and the electric insulating film 19 is arranged. A non-disposed region of the electrical insulating film. The electrically insulating film non-arrangement region constitutes the communication path 41. Thereby, formation of the communicating path 41 can be realized simply and easily.

  In the light emitting / receiving module M1, the second surface 10b of the first substrate 10 and the third surface 20a of the second substrate 20 are a conductor film arrangement region in which the electrode pads 17 are arranged and a conductor in which the electrode pads 17 are not arranged. A film non-arrangement region. The conductor film non-arrangement region constitutes the communication path 41. Thereby, formation of the communicating path 41 can be realized simply and easily.

In the light projecting / receiving module M <b> 1, the space 40 is defined by the first recess 11 formed in the first substrate 10 and the second substrate 20. The first concave portion 11 formed in the first substrate 10 is an element arrangement surface (region 11b ₁ ) as a surface of the first concave portion 11, and a light reflecting surface (first one) located outside the element arrangement surface. Inner surface 11c). Thereby, the light projecting / receiving module M1 in which the light emitting element EE is arranged on the first substrate 10 side is realized.

In the light projecting / receiving module M1, the space portion 40 is positioned on each of the first substrate 10 and the second substrate 20, and is opposed to each other in the direction in which the second surface 10b and the third surface 20a are opposed to each other, A light reflecting surface (the surface of the region 11b ₂ and the second metal film 22) that reflects the light emitted from the EE faces. Thereby, the light emitted from the light emitting element EE can be efficiently guided to each through hole 24.

  The second metal film 22 disposed on the third surface 20a side of the second substrate 20 suppresses the light R1 emitted from the light emitting element EE from passing through the second substrate 20 and reaching the second recess 21. . That is, the second metal film 22 functions as a light shielding film. Accordingly, it is possible to suppress the light R1 emitted from the light emitting element EE from entering the light receiving element RE without being reflected by the object OBJ.

  Next, a modified example of the light projecting / receiving module M1 according to the present embodiment will be described with reference to FIGS. This modification is different from the above-described embodiment with respect to the arrangement of the light emitting elements EE. Hereinafter, overlapping description with the above-described embodiment will be omitted, and differences will be mainly described. FIG. 10 is a perspective view showing a second substrate provided in the light projecting / receiving module according to the modification of the present embodiment. FIG. 11 is a diagram for explaining a cross-sectional configuration of a light projecting / receiving module according to a modification of the present embodiment.

  The light projecting / receiving module M1 according to this modification also includes a light emitting element EE, a light receiving element RE, a first substrate 10, a second substrate 20, and a protective plate 30, as shown in FIGS. The structure 1 is provided. As shown in FIG. 10, the second metal film 22 has a first portion 22a and a second portion 22b that are positioned so as to be separated from each other. The first portion 22a and the second portion 22b are electrically insulated from each other. The second portion 22b extends from the central portion of the region located between the two through holes 24 on the third surface 20a in a direction along the longitudinal direction of the opening shape of the through hole 24. The second portion 22b has a substantially strip shape.

Surface of the second metal film 22 includes a region 20a ₁ located in the center of the third surface, a region 20a ₂ located outside the region 20a ₁ so as to surround a region 20a _1, a. The region 20a ₁ is configured by the surface of the first portion 22a. In the region 20a ₁ , the light emitting element EE is arranged. That is, the region 20a ₁ functions as an element arrangement surface on which the light emitting element EE is arranged, and the light emitting element EE is arranged on the second substrate 20 (third surface 20a) side. The light emitting element EE is arranged so that the light emitting surface faces the first substrate 10 side. Emitting element EE is the first part 22a electrically connected to constitute the region 20a _1. The light emitting element EE is also electrically connected to the second portion 22b through a bonding wire. Also in the present embodiment, the light emitting element EE and the light receiving element RE are arranged on the same virtual axis L.

  The first portion 22 a is electrically connected to at least one electrode pad 18 excluding the electrode pad 18 electrically connected to the light receiving element RE among the plurality of electrode pads 18. The second portion 22b includes at least one electrode pad 18 excluding the electrode pad 18 electrically connected to the light receiving element RE and the electrode pad 18 electrically connected to the first portion 22a among the plurality of electrode pads 18. Is electrically connected to the second portion 12b. Similar to the light receiving element RE, the light emitting element EE is electrically connected to the external electrode 15 through the electrode pad 18, the bump conductor 27, the electrode pad 17, and the through wiring 16.

  Also in this modification, when the light R1 is emitted from the light emitting element EE, the emitted light R1 is reflected by the first metal film 12 and the second metal film 22 in the space portion 40, and each through hole 24 is reflected. Led to. The light guided to each through hole 24 passes through the protection plate 30 and is emitted from the light projecting / receiving module M1. The reflected light R2 from the object OBJ passes through the protection plate 30 and enters the light receiving element RE. Therefore, the light projecting / receiving module M1 according to the present modification can also ensure optical characteristics and reduce the size with a simple configuration. Further, the increase in the internal pressure of the light projecting / receiving module M1 is suppressed, and the protective plate 30 can be arranged at a desired position.

In the light projecting / receiving module M1 according to this modification, the space 40 is defined by the first recess 11 formed in the first substrate 10 and the second substrate 20, and the second substrate 20 is the third substrate. The first recess 11 formed on the first substrate 10 including the element arrangement surface (region 20a ₁ ) on the side of the surface 20a has a third surface 20a and a fourth surface 20b as the surfaces of the first recess 11. It includes a light reflecting surface (first inner side surface 11c) located outside the element arrangement surface when viewed from the opposite direction. For this reason, the light projecting / receiving module M1 in which the light emitting element EE is arranged on the second substrate 20 side is realized.

  Next, another modification of the light projecting / receiving module M1 according to the present embodiment will be described with reference to FIG. This modification is different from the above-described embodiment with respect to the number and shape of the through holes 24. Hereinafter, overlapping description with the above-described embodiment will be omitted, and differences will be mainly described. FIG. 12 is a perspective view showing a light projecting / receiving module according to a modification of the present embodiment.

As shown in FIG. 12, in the light projecting / receiving module M <b> 1 according to this modification, four through holes 24 are formed in the second substrate 20. The through hole 24 extends in a direction in which the third surface 20a and the fourth surface 20b face each other. One end of each through-hole 24, in the third surface 20a, is open in a region opposed to a region 11b ₂ of the first bottom surface 11b and the first inner surface 11c. The other end of each through hole 24 opens to the fourth surface 20b.

  The four through holes 24 are formed at positions that are rotationally symmetric with respect to the virtual axis L. That is, one end of each through hole 24 is positioned rotationally symmetric with respect to the virtual axis L on the third surface 20a, and the other end of each through hole 24 rotates with respect to the virtual axis L on the fourth surface 20b. Located symmetrically. The opening shape at one end and the other end of each through-hole 24 is substantially circular. The light receiving element RE (second recess 21) is positioned so as to be surrounded by the four through holes 24 when viewed from the direction orthogonal to the fourth surface 20b. The distance from the light receiving element RE to each through hole 24 is equal.

  Also in this modification, when the light R1 is emitted from the light emitting element EE, the emitted light R1 is reflected by the first metal film 12 and the second metal film 22 in the space portion 40, and each through hole 24 is reflected. Led to. The light guided to each through hole 24 passes through the protection plate 30 and is emitted from the light projecting / receiving module M1. The number and shape of the through holes 24 are not limited to the numbers and shapes described in the above-described embodiment and this modification. The plurality of through holes 24 may be formed at positions that are rotationally symmetric with respect to the virtual axis L.

  Next, with reference to FIG. 13, the further modification of the light projection / reception module M1 which concerns on this embodiment is demonstrated. This modification is different from the above-described embodiment regarding the configuration of the communication path 41. Hereinafter, overlapping description with the above-described embodiment will be omitted, and differences will be mainly described. FIG. 13 is a diagram for explaining a cross-sectional configuration of a light projecting / receiving module according to a modification of the present embodiment.

  As shown in FIG. 13, in the present modification, a groove T is formed on the first substrate 10 on the second surface 10 b side. The second substrate 20 also has a groove T formed on the third surface 20a side. Each groove | channel T is located so that it may mutually oppose in the state arrange | positioned so that the 1st board | substrate 10 and the 2nd board | substrate 20 may mutually oppose. The groove T extends across the space 40 and the outer surface of the structure 1. Each groove T functions as a communication path 41. In this case, the formation of the communication path 41 can be realized simply and easily. The groove T may be formed in only one of the first substrate 10 and the second substrate 20. The depth of the groove T is, for example, about 25 μm.

  As mentioned above, although embodiment of this invention and the modification of embodiment have been demonstrated, this invention is not necessarily limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the summary.

  In the embodiment described above, the structure 1 is formed with the communication path 41 constituted by the electric insulation film non-arrangement region and the communication path 41 constituted by the conductor film non-arrangement region, but is not limited thereto. . The structure 1 only needs to be formed with at least one of the communication passage 41 constituted by the electric insulation film non-arrangement region and the communication passage 41 constituted by the conductor film non-arrangement region. Even in this case, when the plurality of through holes 24 are closed by the protective plate 30, the gas existing in the space 40 of the light projecting / receiving module M1 passes through the communication path 41 and is outside the structure 1. Discharged.

  It is sufficient that at least one of the second surface 10b of the first substrate 10 and the third surface 20a of the second substrate 20 has an electric insulating film non-arrangement region. Even in this case, the communication path 41 can be configured by the electric insulating film non-arrangement region. Further, at least one of the second surface 10b of the first substrate 10 and the third surface 20a of the second substrate 20 only needs to have a conductor film non-arrangement region. Even in this case, the communication path 41 can be configured by the conductor film non-arrangement region.

  The first inner surface 11c does not necessarily have to be inclined in a tapered shape. The first inner surface 11c may extend in a direction orthogonal to the first bottom surface 11b. That is, the shape and size of the first opening 11a may be the same as the shape and size of the first bottom surface 11b. In order to efficiently guide the light R1 emitted from the light emitting element EE to each through hole 24, the first inner side surface 11c is preferably inclined in a tapered shape. The shapes of the first opening 11a and the first bottom surface 11b are not limited to the circular shape described above, and may be other shapes (for example, a rectangular shape).

  When the reflectance of the first substrate 10 and the second substrate 20 is relatively high with respect to the light R1 emitted from the light emitting element EE, the first metal film 12 and the second metal film 22 are not necessarily required. In order to efficiently guide the light R1 emitted from the light emitting element EE to each through hole 24, the first metal film 12 and the second metal film 22 are preferably disposed so as to face the space 40. .

  In this embodiment and this modification, the electrical connection between the first substrate 10 and the second substrate 20 is realized at the positions of the edges of the first and second substrates 10, 20. Without being limited thereto, electrical connection between the first substrate 10 and the second substrate 20 may be realized at a position inside the edge.

1 ... structure, 10 ... first substrate, 10a ... first surface, 10b ... second surface 11 ... first recess, 11b 1 _... region, 12 ... first metal layer, 20 ... second substrate, 20a ... first Three surfaces, 20b ... fourth surface, 21 ... second recess, 22 ... second metal film, 24 ... through hole, 30 ... protection plate, 40 ... space portion, 41 ... communication path, EE ... light emitting element, L ... virtual Axis, M1... Projecting and receiving module, RE.

Claims (8)

A light emitting and receiving module comprising a light emitting element and a light receiving element, projecting light emitted from the light emitting element onto an object, and receiving light reflected from the object by the light receiving element;
A first substrate having a first surface and a second surface facing each other, a third surface and a fourth surface facing each other, and the third surface facing the second surface; A second substrate that is disposed on the second substrate so as to face the fourth surface, and a protective plate that transmits light emitted from the light emitting element and light from the object. Equipped with a body,
In the structure, the light emitting element is positioned, the space configured to be defined by the first substrate and the second substrate, the light receiving element is positioned, and the first substrate A recess configured to be recessed from the fourth surface side of the two substrates, and a communication path communicating the space to the outside of the structure, are formed,
The light emitting element and the light receiving element are located on a virtual axis extending in a direction in which the first surface and the second surface face each other,
The space portion is located on one of the first substrate and the second substrate and has an element arrangement surface on which the light emitting element is arranged, located on the first substrate, and the light emission. A light reflecting surface that reflects and guides the light emitted from the element to the second substrate side,
The second substrate has one end opened in a region of the third surface facing the light reflecting surface, the other end opened in the fourth surface, and the third surface and the fourth surface are A plurality of through holes extending in opposite directions are formed at positions that are rotationally symmetric with respect to the virtual axis,
The protective plate is a light projecting / receiving module disposed on the second substrate so as to at least close the recess and the plurality of through holes.   The communication path is formed between the second surface of the first substrate and the third surface of the second substrate so as to extend between the space and the outer surface of the structure. The light projecting / receiving module according to claim 1. At least one of the second surface of the first substrate and the third surface of the second substrate has an electric insulating film arrangement region in which an electric insulating film is arranged, and an electric in which the electric insulating film is not arranged. An insulating film non-arrangement region,
The light projecting / receiving module according to claim 2, wherein the electric insulating film non-arrangement region constitutes the communication path. At least one of the second surface of the first substrate and the third surface of the second substrate has a conductor film arrangement region in which a conductor film is arranged and a conductor film non-arrangement in which the conductor film is not arranged An area, and
The light projecting / receiving module according to claim 2 or 3, wherein the conductor film non-arrangement region constitutes the communication path. A groove is formed in at least one of the second surface side of the first substrate and the third surface side of the second substrate,
The light projecting / receiving module according to any one of claims 2 to 4, wherein the groove constitutes the communication path. The space is defined by a recess formed in the first substrate and the second substrate;
The said recessed part currently formed in said 1st board | substrate contains the said element arrangement | positioning surface and the said light reflection surface located in the outer side of this element arrangement | positioning surface as a surface of this recessed part. The light projecting / receiving module according to any one of? The space is defined by a recess formed in the first substrate and the second substrate;
The second substrate includes the element arrangement surface on the third surface side,
The light reflecting surface in which the concave portion formed in the first substrate is located outside the element arrangement surface as viewed from a direction in which the third surface and the fourth surface face each other as a surface of the concave portion. The light projecting / receiving module according to any one of claims 1 to 5, further comprising:   Light emitted from the light emitting element is located in each of the first substrate and the second substrate in the space portion, and is opposed to each other in a direction in which the second surface and the third surface are opposed to each other. The light projecting / receiving module according to any one of claims 1 to 7, wherein a light reflecting surface that reflects the light is facing.

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