Optical waveguide, package for housing electronic element, electronic module, and electronic device

Abstract

To provide an optical waveguide, a package for housing an electronic element, an electronic module and an electronic device which can increase the quantity of a part of light and can be made compact.SOLUTION: The optical waveguide includes a cladding, a first core, and a second core. The first core has a first end surface and a plurality of second end surfaces. The second core has a third end surface and a fourth end surface. The first core includes a first linear part, a merging part, and a plurality of first parts. The first straight portion includes a first end surface. The merging portion is connected to the first linear portion. The first portion is connected to the merging portion and includes a second end surface. The second core includes a second straight portion and a first curved portion. The second straight portion includes the third end surface. The first curved portion is connected to the second linear portion. In a first direction in which the first straight portion extends, a distance from the first end surface to a boundary between the first straight portion and the merging portion is larger than a distance from the first end surface to a boundary between the second straight portion and the first curved portion.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to an optical waveguide, a package for housing an electronic element, an electronic module, and an electronic device. [Background technology]

[0002] Patent Document 1 discloses an optical waveguide in which a plurality of cores are positioned apart from one another, as an optical waveguide used in a light source module of an image display device such as a projector or a head-mounted display. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 090333 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional optical waveguides sometimes lack the amount of light in some areas. In addition, miniaturization is also required in optical waveguide design.

[0005] Therefore, an object of the present disclosure is to provide an optical waveguide, an electronic element housing package, an electronic module, and an electronic device that can increase the amount of light emitted from a portion of the light and can be made smaller. [Means for solving the problem]

[0006] (1) One embodiment of an optical waveguide according to the present disclosure comprises: a cladding having a first side; a first core located within the cladding and having a first end face exposed to the first side face and a plurality of second end faces; a second core located in the cladding and spaced apart from the first core, the second core having a third end face exposed to the first side surface and a fourth end face, the first core has a first linear portion, a junction portion, and a plurality of first portions, the number of which is the same as the number of the second end faces; the first linear portion includes the first end surface and has a constant width; the joining portion is connected to the first straight portion, and the joining portion has a width that decreases as it approaches the first straight portion, each of the first portions is connected to the junction portion and includes one of the second end surfaces; the second core has a second straight portion and a first curved portion, the second linear portion includes the third end surface and has a constant width; the first curved portion is connected to the second straight portion, has a curved shape, and the distance between the first curved portion and the first core decreases as the first curved portion approaches the second straight portion, When the boundary between the first straight portion and the confluence portion is defined as a first point and the boundary between the second straight portion and the first curved portion is defined as a second point, in a first direction in which the first straight portion extends, the distance from the first end face to the first point is greater than the distance from the first end face to the second point.

[0007] (2) One embodiment of the optical waveguide according to the present disclosure is The optical waveguide according to (1), The first portions are spaced apart from one another at locations where they connect to the junction.

[0008] (3) One embodiment of the optical waveguide according to the present disclosure is The optical waveguide according to (2), At positions where the first portions connect to the junction portion, the distance between the first portions is smaller than the distance between the first core and the second core.

[0009] (4) One embodiment of the optical waveguide according to the present disclosure is The optical waveguide according to any one of (1) to (3), The width of the first linear portion is smaller than the width of the second linear portion.

[0010] (5) One embodiment of the optical waveguide according to the present disclosure is The optical waveguide according to any one of (1) to (4), The maximum width of the joining portion is greater than the maximum width of the second core.

[0011] (6) One embodiment of the optical waveguide according to the present disclosure comprises: The optical waveguide according to any one of (1) to (5), In a side view taken along the width direction of the first straight portion, the entire joining portion overlaps with the first curved portion.

[0012] (7) One embodiment of the optical waveguide according to the present disclosure comprises: The optical waveguide according to any one of (1) to (6), The first core allows red light to enter.

[0013] (8) One embodiment of the optical waveguide according to the present disclosure comprises: The optical waveguide according to any one of (1) to (7), The area of ​​the first end face is smaller than the area of ​​any of the second end faces.

[0014] (9) One embodiment of the optical waveguide according to the present disclosure is The optical waveguide according to any one of (1) to (8), The area of ​​each of the second end faces is larger than the area of ​​the fourth end face.

[0015] (10) One embodiment of the optical waveguide according to the present disclosure comprises: The optical waveguide according to any one of (1) to (9), a normal direction of the first end face is the same as a normal direction of the third end face; The distance between the center position of the first end face and the center position of the third end face is 1 to 10 μm.

[0016] (11) One embodiment of the optical waveguide according to the present disclosure comprises: The optical waveguide according to any one of (1) to (10), The path length from any of the second end faces to the first end face is shorter than the path length from the fourth end face to the third end face.

[0017] (12) One embodiment of the optical waveguide according to the present disclosure comprises: The optical waveguide according to any one of (1) to (11), a third core located in the cladding on the opposite side of the first core from the second core and spaced apart from the first core, the third core having a fifth end face exposed to the first side surface and a sixth end face; the third core has a third straight portion and a second curved portion, the third linear portion includes the fifth end surface and has a constant width, the second curved portion is connected to the third straight portion, has a curved shape, and the distance between the second curved portion and the first core decreases as the second curved portion approaches the third straight portion, When the boundary between the third straight portion and the second curved portion is defined as a third point, the distance from the first end face to the first point in the first direction is greater than the distance from the first end face to the third point.

[0018] (13) One embodiment of the electronic element storage package according to the present disclosure comprises: A substrate; an optical waveguide according to any one of (1) to (12) above located on the substrate; an electrode located in an element mounting area above the substrate; the cladding has a recess in which the element mounting region is located, The second end face and the fourth end face are exposed in the recess.

[0019] (14) One embodiment of the electronic module according to the present disclosure includes: The package for housing an electronic element according to (13) above; an electronic element located in the element mounting area; a lid located on the cladding and covering the element mounting area, the electrodes include a first electrode and a second electrode; The electronic elements include a first electronic element connected to the first electrode and a second electronic element connected to the second electrode.

[0020] (15) One embodiment of the electronic device according to the present disclosure comprises: The electronic module (14) above; a display unit, the electronic element is a light-emitting element, The display unit performs display using light emitted from the electronic module. [Effects of the Invention]

[0021] According to the present disclosure, it is possible to obtain an optical waveguide, an electronic element housing package, an electronic module, and an electronic device that can increase the amount of light of a portion of light and can be made smaller. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a perspective view of an electronic module according to one embodiment of the present disclosure. [Figure 2] FIG. 2 is a plan view of the electronic module. [Figure 3] 3 is a cross-sectional view of the electronic module taken along the line AA in FIG. 2. [Figure 4] FIG. 2 is a side view of the electronic module. [Figure 5] FIG. 2 is a plan view illustrating the shape of a core. [Figure 6] FIG. [Figure 7] FIG. 10 is a perspective view of an electronic module according to another embodiment of the present disclosure. [Figure 8] FIG. 10 is a perspective view of an electronic module according to another embodiment of the present disclosure. [Figure 9] FIG. 1 is a perspective view of an electronic device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. However, for the sake of convenience, the drawings below show simplified views of the main components necessary for explaining the embodiments. Therefore, the embodiments of the present disclosure may include any components not shown in the drawings. Furthermore, the drawings do not necessarily faithfully represent the dimensional proportions of the actual components.

[0024] For convenience, directions are defined using an XYZ Cartesian coordinate system. The plane on which the first linear portion and the second linear portion are located is the XY plane. The first direction in which the first linear portion of the first core extends is the X direction, the direction perpendicular to the X direction in the XY plane is the Y direction, and the direction perpendicular to the XY plane is the Z direction. The positive side of the X direction is the right side, the positive side of the Y direction is the front side, and the positive side of the Z direction is the top side. In this disclosure, "planar view" refers to viewing from the top side of the optical waveguide (the positive side in the Z direction), and includes planar perspective viewing.

[0025] In the following description, expressions such as "constant," "orthogonal," "vertical," "parallel," or "equal" may be used. These expressions do not necessarily mean "constant," "orthogonal," "vertical," "parallel," or "equal" in their strict sense. In other words, these expressions allow for deviations due to, for example, manufacturing precision, installation precision, etc. Numerical ranges expressed using "to" include the numerical values ​​before and after it as the lower and upper limits, respectively.

[0026] [Optical waveguide] 1, the optical waveguide 10 has a cladding 14, a first core 11, and a second core 12. The cladding 14 has a first side surface 141. The first core 11 is located within the cladding 14. The second core 12 is located within the cladding 14 and spaced apart from the first core 11.

[0027] The first core 11 has a first end face 111 exposed at the first side surface 141 and a plurality of second end faces 117. The first end face 111 can be used as an output end face of the first core 11. The second end face 117 can be used as an input end face of the first core 11.

[0028] As shown in FIGS. 5 and 6 , the first core 11 has a first linear portion 112, a merging portion 114, and a plurality of first portions 115, the number of which is the same as the number of second end faces 117. Each of the plurality of first portions 115 is connected to the merging portion 114 and includes one of the second end faces 117. The plurality of second end faces 117 can be used as an incident end face for light of the same color. Having a plurality of second end faces 117 in the first core 11 allows for the use of multiple light-emitting elements of the same color as the electronic element 31, thereby increasing the amount of light passing through the first core 11. Increasing the amount of light by using multiple light-emitting elements of the same color reduces the amount of heat generated by each light-emitting element compared to increasing the amount of light using a single light-emitting element. Furthermore, using multiple light-emitting elements of the same color but with different wavelengths reduces the possibility of speckle noise due to interference compared to using only one light-emitting element of the same color and wavelength. The number of second end faces 117 and first portions 115 may be two as shown in FIG. 5, etc., or may be three or more.

[0029] The junction section 114 is connected to the first straight section 112, and its width decreases as it approaches the first straight section 112. The width of the junction section 114 decreases as it approaches the first straight section 112, thereby improving the accuracy of the emitted light. The rate of decrease in width at the junction section 114 may or may not be constant. The rate of decrease in width refers to the amount of decrease in width per dimension (length) in the direction in which the junction section 114 extends.

[0030] The first linear portion 112 includes the first end face 111 and has a constant width. This makes it possible to stabilize the beam shape and intensity distribution of the emitted light at the first end face 111. In particular, when the light passing through the first core 11 is a multi-mode in the transverse mode, it is possible to further stabilize the beam shape and intensity distribution of the emitted light.

[0031] The cross-sectional area of ​​the confluence portion 114 may become smaller as it approaches the first straight portion 112. More specifically, since the width of the confluence portion 114 becomes smaller as it approaches the first straight portion 112, for example, if the thickness of the confluence portion 114 is constant, the cross-sectional area of ​​the confluence portion 114 becomes smaller as it approaches the first straight portion 112.

[0032] In this disclosure, the width of the core refers to the dimension in the XY plane in a direction perpendicular to the extension direction of the core. For example, the width of the first linear portion 112 is the dimension in the Y direction. In this disclosure, the thickness of the core refers to the dimension in the Z direction. In this disclosure, the cross-sectional area of ​​the core refers to the area of ​​the cross section perpendicular to the extension direction of the core.

[0033] The second core 12 has a third end face 121 exposed at the first side face 141, and a fourth end face 128. The third end face 121 can be used as an output end face of the second core 12. The fourth end face 128 can be used as an input end face of the second core 12.

[0034] The second core 12 also has a second straight portion 122 and a first curved portion 124. The second straight portion 122 includes the third end face 121 and has a constant width. This makes it possible to stabilize the beam shape and light intensity distribution of the emitted light at the third end face 121. The first curved portion 124 is connected to the second straight portion 122 and has a curved shape, with the distance from the first core 11 decreasing as it approaches the second straight portion 122.

[0035] The boundary between the first straight portion 112 and the junction 114 is defined as a first point 113, and the boundary between the second straight portion 122 and the first curved portion 124 is defined as a second point 123. In this case, in a first direction (X direction) in which the first straight portion 112 extends, a distance D1 from the first end face 111 to the first point 113 is greater than a distance D2 from the first end face 111 to the second point 123. In other words, in the first direction (X direction), a distance D1 from the first end face 111 to the boundary between the first straight portion 112 and the junction 114 is greater than a distance D2 from the first end face 111 to the boundary between the second straight portion 122 and the first curved portion 124. In other words, in the first direction (X direction), a distance from the third end face 121 to the first point 113 is greater than a distance from the third end face 121 to the second point 123. As a result, the junction portion 114 and the second straight portion 122 are no longer adjacent to each other in the Y direction, and the second straight portion 122 can be brought closer to the first straight portion 112 without considering the width of the junction portion 114, which gradually becomes larger than the width of the first straight portion 112. This makes it possible to reduce the distance between the first straight portion 112 and the second straight portion 122, and ultimately to reduce the size of the optical waveguide 10.

[0036] The direction in which the second linear portion 122 extends may be the same as the first direction (X direction) in which the first linear portion 112 extends. In other words, the first linear portion 112 and the second linear portion 122 may be parallel to each other.

[0037] The path length of the first straight portion 112 may be longer than the path length of the second straight portion 122. For example, when the first side surface 141 is perpendicular to the first straight portion 112 and the first straight portion 112 and the second straight portion 122 are parallel, the path length of the first straight portion 112 is longer than the path length of the second straight portion 122.

[0038] The optical waveguide 10 may further have a third core 13. The third core 13 may be located within the cladding 14 on the opposite side of the first core 11 from the second core 12, and spaced apart from the first core 11. The third core 13 may have a fifth end face 131 exposed at the first side surface 141, and a sixth end face 138. The fifth end face 131 may be used as an output end face of the third core 13. The sixth end face 138 may be used as an input end face of the third core 13.

[0039] The third core 13 may have a third straight portion 132 and a second curved portion 134. The third straight portion 132 may include the fifth end face 131 and have a constant width. This makes it possible to stabilize the beam shape and light intensity distribution of the emitted light at the fifth end face 131. The second curved portion 134 may be connected to the third straight portion 132 and have a curved shape such that the distance from the first core 11 decreases as the second curved portion 134 approaches the third straight portion 132.

[0040] When the third core 13 is provided, the light propagation efficiency can be easily improved by making the third core 13 have the same or similar positional relationship and shape with respect to the first core 11 as the second core 12. This makes it easier to emit light from each core with appropriate resolution.

[0041] When the boundary between the third straight portion 132 and the second curved portion 134 is defined as a third point 133, a distance D1 from the first end face 111 to the first point 113 in the first direction (X direction) may be greater than a distance D3 from the first end face 111 to the third point 133. In other words, in the first direction (X direction), a distance D1 from the first end face 111 to the boundary between the first straight portion 112 and the junction 114 is greater than a distance D3 from the first end face 111 to the boundary between the third straight portion 132 and the second curved portion 134. In other words, in the first direction (X direction), a distance from the fifth end face 131 to the first point 113 is greater than a distance from the fifth end face 131 to the third point 133. As a result, the junction portion 114 and the third straight portion 132 are no longer adjacent to each other, and the third straight portion 132 can be brought closer to the first straight portion 112 without considering the width of the junction portion 114, which gradually becomes wider than the first straight portion 112. This makes it possible to reduce the distance between the first straight portion 112 and the third straight portion 132, thereby further miniaturizing the optical waveguide 10. The path length of the first straight portion 112 may be longer than the path length of the third straight portion 132.

[0042] The direction in which the third linear portion 132 extends may be the same as the first direction (X direction) in which the first linear portion 112 extends. In other words, the first linear portion 112 and the third linear portion 132 may be parallel to each other.

[0043] The first side surface 141 is the surface from which light is emitted. The first side surface 141 may or may not be perpendicular to the first linear portion 112. Furthermore, the first side surface 141 may or may not be flat. The first side surface 141 may have one or more steps in plan view. For example, if the first side surface 141 is not a flat surface perpendicular to the first linear portion 112, the positions of the first end surface 111, the second end surface 117, and the third end surface 121 may be misaligned in the first direction (X direction).

[0044] The first core 11 may be capable of emitting red light. In other words, the first core 11 may be a core for red light. Red light refers to light with a wavelength of 600 to 780 nm. By using the first core 11 having multiple second end faces 117 for red light, multiple red light-emitting elements can be used. There is a high possibility that the amount of red light will be insufficient or reduced, but by using multiple red light-emitting elements, the amount of red light can be easily increased to the required amount. Furthermore, red light-emitting elements are more susceptible to deterioration due to high temperatures than light-emitting elements of other colors, but by using multiple red light-emitting elements, the amount of heat generated by each red light-emitting element can be reduced, making it less likely for the red light-emitting elements to deteriorate.

[0045] When the first core 11 is a core for red light, the second core 12 may be a core for green light, and the third core 13 may be a core for blue light, for example. Alternatively, when the first core 11 is a core for red light, the second core 12 may be a core for blue light, and the third core 13 may be a core for green light, for example.

[0046] As shown in FIG. 6 , the first portions 115 may be spaced apart from one another at positions where they connect to the junction 114. In other words, the first portions 115 do not have to overlap one another when viewed along the direction in which the junction 114 extends. In other words, the first portions 115 may be connected to the junction 114 at positions offset from one another in the width direction of the junction 114. This improves the accuracy of resist exposure and core material etching at the connection points between the junction 114 and the first portions 115 when forming the first core 11. This makes it easier to control the shape of the first core 11 as desired at the connection points between the junction 114 and the first portions 115, and also reduces the possibility of the first core 11 being chipped in the vertical direction (Z direction).

[0047] When the first portions 115 are spaced apart from one another at positions where they connect to the merging portion 114, the distance d11 between the multiple first portions 115 at the positions where the first portions 115 connect to the merging portion 114 may be smaller than the distance d12 between the first core 11 and the second core 12. This makes it easier to miniaturize the optical waveguide 10 in the width direction of the merging portion 114. It also reduces the possibility that the distance between the light-emitting element that inputs light to the first core 11 and the light-emitting element that inputs light to the third core 13 becomes too close. In addition, since the distance d11 between the first portions 115 is not too large, the width of the merging portion 114 at the connection point with the first portion 115 does not become too large. This reduces the degree of reduction in the width of the merging portion 114 in the direction in which the merging portion 114 extends, and light leakage due to the width reduction is likely to be reduced.

[0048] Similarly, at the position where the first portions 115 connect to the junction 114, the distance d11 between the multiple first portions 115 may be smaller than the distance d13 between the first core 11 and the third core 13. This reduces the possibility that the light-emitting element that causes light to enter the first core 11 and the light-emitting element that causes light to enter the third core 13 will be too close to each other.

[0049] The maximum width d14 of the merging section 114 may be larger than the maximum width of the second core 12. Similarly, the maximum width d14 of the merging section 114 may be larger than the maximum width of the third core 13. With this configuration, the maximum width d14 of the merging section 114 is increased, and light can be spread over the entire first core 11, allowing light to be emitted relatively uniformly from the first end face 111. In other words, the possibility of unevenness occurring in the light emitted from the first core 11 is reduced. This allows the first core 11 to emit light in a form that depends to some extent on the cross-sectional shape of the first core 11.

[0050] In a side view taken along the width direction (Y direction) of the first straight portion 112, all of the converging portions 114 may overlap with the first curved portions 124. Similarly, in a side view taken along the width direction of the first straight portion 112, all of the converging portions 114 may overlap with the second curved portions 134. Light is more likely to leak from the converging portions 114, the first curved portions 124, and the second curved portions 134 than from straight portions. When all of the converging portions 114 overlap with the first curved portions 124 or the second curved portions 134 in a side view, light that leaks from one core is less likely to enter another core. This makes it easier to obtain appropriate resolution and appropriately improves light propagation efficiency.

[0051] First portion 115 may have a curved shape as shown in Fig. 5 etc., or may be linear. The width of first portion 115 may decrease as it approaches confluence 114, or may be constant.

[0052] The width of the first linear portion 112 may be smaller than the width of the second linear portion 122. As a result, when the thicknesses of the first linear portion 112 and the second linear portion 122 are the same, the area of ​​the first end face 111 is smaller than the area of ​​the third end face 121. By reducing the area of ​​the output end face, the beam diameter of the output light can be reduced. Furthermore, since red light has a longer wavelength than green light and blue light, the divergence angle of the output light at the output end face is likely to be larger. Therefore, when the first core 11 is used for red light and the second core 12 is used for green light or blue light, by making the area of ​​the first end face 111 smaller than the area of ​​the third end face 121, it becomes easier to match the beam diameter of the red light to the beam diameter of the green light or the blue light at a point the same distance from the output end face. This makes it easier to adjust the resolution appropriately. The width of the first linear portion 112 may be the same as the width of the second linear portion 122. In the present disclosure, the spread angle can also be referred to as the divergence angle.

[0053] Similarly, the width of the first straight portion 112 may be smaller than the width of the third straight portion 132. This makes it easier to adjust the resolution appropriately when the first core 11 is for red light and the third core 13 is for green light or blue light. The width of the first straight portion 112 may be the same as the width of the third straight portion 132.

[0054] The path lengths of the first straight line portion 112, the second straight line portion 122, and the third straight line portion 132 may each be, for example, approximately 50 to 200 μm. If the path lengths of the first straight line portion 112, the second straight line portion 122, and the third straight line portion 132 are 50 μm or more, the beam shape is more likely to be stabilized. If the path lengths of the first straight line portion 112, the second straight line portion 122, and the third straight line portion 132 are 200 μm or less, light loss is less likely to become too large.

[0055] The first core 11 may have a fourth straight portion 116 connected to the first portion 115. The fourth straight portion 116 may include a second end face 117. When the first core 11 has the fourth straight portion 116 including the second end face 117, leakage of light from the first core 11 is reduced.

[0056] The second core 12 may have a fifth straight portion 127 that connects to the first curved portion 124. The fifth straight portion 127 may include a fourth end face 128. When the second core 12 has the fifth straight portion 127 that includes the fourth end face 128, leakage of light from the second core 12 is reduced. The extending direction of the fifth straight portion 127 may be the same as the extending direction of the fourth straight portion 116. In other words, the fourth straight portion 116 and the fifth straight portion 127 may be parallel to each other.

[0057] The third core 13 may have a sixth straight portion 137 connected to the second curved portion 134. The sixth straight portion 137 may include a sixth end face 138. When the third core 13 has the sixth straight portion 137 including the sixth end face 138, leakage of light from the third core 13 is reduced. The direction in which the sixth straight portion 137 extends may be the same as the direction in which the fourth straight portion 116 extends. In other words, the fourth straight portion 116 and the sixth straight portion 137 may be parallel to each other.

[0058] The path length of the fifth straight portion 127 and the path length of the sixth straight portion 137 may be equal to each other or may be different from each other. When the path length of the fifth straight portion 127 and the path length of the sixth straight portion 137 are equal to each other, the loss of light before entering the first curved portion 124 and the second curved portion 134 is approximately the same, thereby reducing unevenness in the amount of light. Accordingly, the amount of heat generated by the passage of light through the fifth straight portion 127 and the sixth straight portion 137 is also approximately the same, thereby reducing the possibility of unevenness in the amount of distortion in the optical waveguide 10. Furthermore, when the fifth straight portion 127 and the sixth straight portion 137 are parallel to each other, the path lengths of the fifth straight portion 127 and the sixth straight portion 137 are equal to each other, thereby canceling out part of the distortion of the second core 12 and the third core 13 due to heat, mainly the distortion component in the Y direction.

[0059] The path length of the fifth straight portion 127 may be approximately 50 times or more the wavelength of the light incident on the second core 12. This makes it possible to keep the influence of scattering and reflection of light from the fourth end face 128 away from the first curved portion 124. The path length of the fifth straight portion 127 may be approximately 300 times or less the wavelength of the light incident on the second core 12. This makes it possible to reduce the possibility of large light loss. Therefore, the path length of the fifth straight portion 127 may be set to, for example, approximately 50 to 300 μm. The path length of the sixth straight portion 137 may also be set in a similar manner depending on its relationship with the wavelength of the light incident on the third core 13.

[0060] The area of ​​any of the second end faces 117 may be larger than the area of ​​the fourth end face 128. This relatively reduces the energy density at the second end face 117, and reduces the increase in temperature near the second end face 117. This reduces the decrease in brightness of the red light-emitting element, whose brightness is likely to decrease due to an increase in temperature, for example, when the first core 11 is for red light. The area of ​​the second end face 117 may be larger than the area of ​​the fourth end face 128, for example, by 5 μm or more. Furthermore, when the light incident on the first core 11 is red light, red light tends to spread more easily than blue or green light. Therefore, by making the area of ​​the second end face 117 larger than the area of ​​the fourth end face 128, the red light can be more efficiently incident on the first core 11.

[0061] Similarly, the area of ​​any of the second end faces 117 may be larger than the area of ​​the sixth end face 138. The width of the second end face 117 may be larger than the width of the fourth end face 128. The width of the second end face 117 may be larger than the width of the fourth end face 128 by, for example, 5 μm or more.

[0062] In the first core 11, the area of ​​the first end facet 111 may be smaller than the area of ​​any of the second end faces 117. This makes it easier to stabilize the beam shape of the light emitted from the first end facet 111. Note that there may be a second end facet 117 that has the same area as the first end facet 111, or there may be a second end facet 117 that has an area smaller than that of the first end facet 111.

[0063] In the second core 12, the area of ​​the third end face 121 may be the same as the area of ​​the fourth end face 128. The width of the second core 12 may be constant from the third end face 121 to the fourth end face 128. The second core 12 has the first curved portion 124 that is curved more greatly than the first core 11, making light more likely to leak in this respect. However, by having a constant width, light leakage caused by changes in width can be reduced. This makes it easier to make the degree of light leakage in the second core 12 similar to the degree of light leakage in the first core 11. The width of the second core 12 may be, for example, 1 to 5 μm. The area of ​​the third end face 121 may be different from the area of ​​the fourth end face 128. The width of the second core 12 does not have to be constant from the third end face 121 to the fourth end face 128.

[0064] Similarly, in the third core 13, the area of ​​the fifth end face 131 may be the same as the area of ​​the sixth end face 138. Furthermore, the width of the third core 13 may be constant from the fifth end face 131 to the sixth end face 138. When the third core 13 has the second curved portion 134 that is curved relatively greatly, light is likely to leak at this point. However, by keeping the width constant, light leakage caused by changes in width can be reduced. This makes it easier to make the degree of light leakage in the third core 13 similar to the degree of light leakage in the first core 11. The width of the third core 13 may be, for example, 1 to 5 μm. The area of ​​the fifth end face 131 may be different from the area of ​​the sixth end face 138. The width of the third core 13 does not have to be constant from the fifth end face 131 to the sixth end face 138.

[0065] When the width of the second core 12 and the width of the third core 13 are constant, the width of the second core 12 and the width of the third core 13 may be the same. This makes the energy density distribution of the light passing through each core closer to symmetry, and the heat distribution also tends to become closer to symmetry. This makes it possible to disperse or alleviate stress caused by expansion due to heat generation.

[0066] The normal direction of the first end face 111 may be the same as the normal direction of the third end face 121. The normal direction refers to a direction perpendicular to the surface. The distance d21 between the center of the first end face 111 and the center of the third end face 121 may be 1 to 10 μm. The normal direction of the first end face 111 may be the same as the normal direction of the fifth end face 131. The distance d22 between the center of the first end face 111 and the center of the fifth end face 131 may be 1 to 10 μm. By emitting multiple light beams, particularly light beams of different wavelengths, at intervals of 10 μm or less, the optical waveguide 10 can easily multiplex and emit the light beams with sufficient resolution. By emitting multiple light beams at intervals of 1 μm or more, the possibility of light beams from one core transferring to another core can be reduced. Furthermore, if the above intervals are 1 μm or more, the possibility of increased processing precision required during manufacturing and increased costs and effort can be reduced. It should be noted that, for example, when the required resolution is low, the intervals d21 and d22 may be 10 μm or more.

[0067] 4, the distance d22 between the center position of the first end face 111 and the center position of the fifth end face 131 may be equal to the distance d21 between the center position of the first end face 111 and the center position of the third end face 121. By positioning the first end face 111, the third end face 121, and the fifth end face 131 sufficiently close to each other and at equal intervals, the light emitted from each end face is likely to be emitted to approximately the same position and in the same direction with sufficient visual accuracy even if it is not combined into a single core.

[0068] 3, the distance d31 between the centers of the second end faces 117, the distance d32 between the center of the fourth end face 128 and the center of the second end face 117 closest to the fourth end face 128, and the distance d33 between the center of the sixth end face 138 and the center of the second end face 117 closest to the sixth end face 138 may all be different. For example, the distances d31, d32, and d33 may each be adjusted taking into account differences in the shape of each core, the amount of heat generated by each light-emitting element, etc. The distances d31, d32, and d33 may be, for example, 200 to 300 μm.

[0069] The path length from any of the second end faces 117 to the first end face 111 may be shorter than the path length from the fourth end face 128 to the third end face 121. Similarly, the path length from any of the second end faces 117 to the first end face 111 may be shorter than the path length from the sixth end face 138 to the fifth end face 131. This allows for a relative reduction in light loss in the first core 11. This reduces the amount of light required to be incident on the first core 11, thereby reducing the impact of heat generation on the light-emitting element that inputs light to the first core 11. Because red light-emitting elements are susceptible to the impact of heat generation, the heat reduction effect is particularly effective when the first core 11 is for red light.

[0070] The first curved portion 124 may have a first arc portion 125 and a second arc portion 126 that curve in opposite directions. The first arc portion 125 and the second arc portion 126 may be directly connected to each other, or may have a straight portion or the like between them. The first arc portion 125 may be connected to the second straight portion 122. The second arc portion 126 may be connected to the fifth straight portion 127. The radius of curvature r1 of the first arc portion 125 and the radius of curvature r2 of the second arc portion 126 may be equal to each other. In this way, the first curved portion 124 is a combination of two symmetrical arc portions, which can reduce light loss in the first curved portion 124. The radius of curvature r1 of the first arc portion 125 and the radius of curvature r2 of the second arc portion 126 may be different from each other.

[0071] The inclined angle t1 of the first arc-shaped portion 125 and the inclined angle t2 of the second arc-shaped portion 126 may be equal to each other. This makes it easier for stresses due to thermal deformation in both portions to be partially canceled out, particularly in the Y-direction component, thereby reducing distortion in the second core 12. Furthermore, the magnitude of distortion that remains uncancelled in the second core 12 is also approximately the same, making it possible to reduce the effect of this remaining distortion on the propagation of light passing through the second core 12. The inclined angle t1 of the first arc-shaped portion 125 and the inclined angle t2 of the second arc-shaped portion 126 may be different from each other.

[0072] The second curved portion 134 may have a third arc portion 135 and a fourth arc portion 136 that curve in opposite directions. The third arc portion 135 and the fourth arc portion 136 may be directly connected to each other, or may have a straight portion or the like between them. The third arc portion 135 may be connected to the third straight portion 132. The fourth arc portion 136 may be connected to the sixth straight portion 137. The radius of curvature r3 of the third arc portion 135 and the radius of curvature r4 of the fourth arc portion 136 may be equal to each other. In this way, the second curved portion 134 is a combination of two symmetrical arc portions, which can reduce light loss in the second curved portion 134. The radius of curvature r3 of the third arc portion 135 and the radius of curvature r4 of the fourth arc portion 136 may be different from each other.

[0073] The inclined angle t3 of the third arc-shaped portion 135 and the inclined angle t4 of the fourth arc-shaped portion 136 may be equal to each other. This makes it easier for stresses due to thermal deformation in both portions to be partially canceled out, particularly in the Y-direction component, thereby reducing distortion in the third core 13. Furthermore, the magnitude of distortion that remains uncancelled in the third core 13 is also approximately the same, making it possible to reduce the effect of this remaining distortion on the propagation of light passing through the third core 13. The inclined angle t3 of the third arc-shaped portion 135 and the inclined angle t4 of the fourth arc-shaped portion 136 may be different from each other.

[0074] The radius of curvature r1 of the first arc-shaped portion 125 and the radius of curvature r3 of the third arc-shaped portion 135 may be different from each other. Furthermore, the circumferential angle t1 of the first arc-shaped portion 125 and the circumferential angle t3 of the third arc-shaped portion 135 may be different from each other. By varying the radius of curvature and / or the circumferential angle between the cores depending on the difference in the likelihood of leakage of light incident on each core, it becomes easier to appropriately adjust the amount of light leakage. Furthermore, the radius of curvature r1 of the first arc-shaped portion 125 and the radius of curvature r3 of the third arc-shaped portion 135 may be equal to each other. The circumferential angle t1 of the first arc-shaped portion 125 and the circumferential angle t3 of the third arc-shaped portion 135 may be equal to each other.

[0075] The curvature radius r1 of the first arc portion 125 and the curvature radius r2 of the second arc portion 126 may be, for example, 3.0 to 4.5 mm. The curvature radius r3 of the third arc portion 135 and the curvature radius r4 of the fourth arc portion 136 may be, for example, 3.5 to 5.0 mm.

[0076] The inclined angle of each arc portion may be, for example, 10.0 to 15.0°. The inclined angle t1 of the first arc portion 125 and the inclined angle t2 of the second arc portion 126 may be smaller than the inclined angle t3 of the third arc portion 135 and the inclined angle t4 of the fourth arc portion 136 by approximately 0.5 to 3°.

[0077] The first core 11, the second core 12, and the third core 13 may all have the same thickness. This makes it easy to adjust the cross-sectional area of ​​each core. The thickness of each core may be, for example, 2 to 10 μm.

[0078] The second end face 117, the fourth end face 128, and the sixth end face 138 may be positioned at the same location in the X direction, or may be shifted in position in the X direction as shown in Figure 2 etc. For example, the second end face 117 may be positioned closest to the first end face 111 in the X direction, followed by the sixth end face 138, and then the fourth end face 128, which is the furthest. These positions can be determined appropriately taking into consideration differences in the amount of heat generated by light passing through each core and differences in light loss.

[0079] The cross section perpendicular to the direction in which each core extends may have a rectangular, trapezoidal, or other shape.

[0080] 1, 3, and 4, the cladding 14 may have protrusions 145 that protrude above each core along the core in a plan view. The height of the protrusions 145 may be, for example, 2 to 10 μm, which is approximately the same as the thickness of each core.

[0081] As shown in FIG. 1 , the cladding 14 may have a recess 144 inside which the element mounting region 23 is located. The cladding 14 may have an optical waveguide portion 142 in which each core is located and a wall portion 143 connecting to the optical waveguide portion 142, and the recess 144 may be surrounded by the optical waveguide portion 142 and the wall portion 143. The second end face 117, the fourth end face 128, and the sixth end face 138 may be exposed on the inner wall of the recess 144. As shown in FIG. 1 , the recess 144 opens to the positive side of the cladding 14 in the Z direction, and does not necessarily have to open to the negative side of the cladding 14 in the Z direction. Furthermore, the recess 144 may penetrate the cladding 14 in the Z direction. The shape of the recess 144 may be rectangular in a plan view or may be another shape.

[0082] The cladding 14 and each core may be made of an optically transparent material. Specifically, the cladding 14 and each core may be made of glass, resin, or the like. More specifically, the cladding 14 may be made of silicon dioxide (SiO2), and each core may be made of silicon oxynitride (SiON), also known as silicon oxynitride.

[0083] The refractive index of each core is greater than the refractive index of the cladding 14. The difference in refractive index between each core and the cladding 14 depends on the structure, such as the shape of each core, but can be set to, for example, about 0.01 to 2.0. This results in an optical waveguide 10 in which light propagates along each core.

[0084] [Package for storing electronic elements] 1, 7, and 8, the package for storing an electronic element 20 may include an optical waveguide 10 and an electrode 21. Furthermore, as shown in FIGS. 1 and 7, the package for storing an electronic element 20 may include a substrate 22.

[0085] When the electronic device housing package 20 has a substrate 22, the optical waveguide 10 may be located on the substrate 22, and the electrode 21 may be located in a device mounting region 23 above the substrate 22. The device mounting region 23 does not necessarily have to be on the substrate 22. The device mounting region 23 may be located on a clad 14 located on the substrate 22, as shown in FIG. 1 .

[0086] The electrode 21 may include a first electrode 211 connected to a first electronic element 311 described below, a second electrode 212 connected to a second electronic element 312, and a third electrode 213 connected to a third electronic element 313. When the clad 14 has a recess 144, the electrode 21 may extend from the inside to the outside of the recess 144, as shown in Fig. 1. The material of the electrode 21 may be Ti, Pt, Au, Al, or the like.

[0087] The substrate 22 may be a silicon substrate. Alternatively, the material of the substrate 22 may be an insulating material such as ceramic. Examples of ceramic include aluminum oxide sintered body, mullite sintered body, silicon carbide sintered body, aluminum nitride sintered body, silicon nitride sintered body, and glass ceramic sintered body. Alternatively, the material of the substrate 22 may be resin. Examples of resin include epoxy resin, polyimide resin, polyester resin, acrylic resin, phenolic resin, and fluororesin.

[0088] The substrate 22 may have an insulating layer on the surface where the clad 14 is located. If the clad 14 has a recess 144, the insulating layer may be exposed at the bottom of the recess 144. The insulating layer may extend over substantially the entire surface of the substrate 22 where the clad 14 is located. If the clad 14 has a recess 144, the insulating layer may be selectively located only at a position that overlaps with the recess 144 in a plan view. The insulating layer does not have to be a uniform plane, and may have internal irregularities. If the material of the insulating layer is the same as the material of the clad 14, the insulating layer may be integral with the clad 14.

[0089] 7 and 8, the electronic element storage package 20 may have a box 24 that encloses the substrate 22, the optical waveguide 10, etc. The box 24 encloses, for example, the optical waveguide 10 except for the upper side (the positive side in the Z direction). The material of the box 24 may be silicon, ceramic, resin, etc. The material of the box 24 may be the same as the material of the substrate 22, or may not be the same.

[0090] The box 24 may have a window 241 located in the direction of emission of light from each core. The window 241 may be a member that simply transmits light, or may be a member that can convert the emitted light into parallel light instead of the lens 33.

[0091] 1, the cladding 14 may have the recess 144, so that the electronic element storage package 20 does not have the box body 24. This allows the electronic element storage package 20 to be made smaller.

[0092] [Electronic Module] 1 and other figures, the electronic module 30 may include an electronic element housing package 20, an electronic element 31, a lid 32, and a lens 33. Note that the lid 32 and the lens 33 are omitted from FIGS.

[0093] The electronic element 31 may be located in the element mounting region 23. The electronic module 30 may include a plurality of light-emitting elements as the electronic element 31. The light-emitting elements are, for example, laser diodes (LDs), each emitting light at a predetermined wavelength. The plurality of light-emitting elements may include, for example, a plurality of first electronic elements 311 that cause light to be incident on each of the plurality of second end surfaces 117, a second electronic element 312 that causes light to be incident on the fourth end surface 128, and a third electronic element 313 that causes light to be incident on the sixth end surface 138. The first electronic element 311 is, for example, a red light-emitting element. The second electronic element 312 is, for example, a green light-emitting element. The third electronic element 313 is, for example, a blue light-emitting element.

[0094] The first electronic element 311 may be connected to the first electrode 211. The second electronic element 312 may be connected to the second electrode 212. The third electronic element 313 may be connected to the third electrode 213. The electronic elements 31 and the electrodes 21 are electrically connected by, for example, a brazing material, a conductive adhesive, a bonding wire 34, or the like.

[0095] The electronic element 31 may be a light-receiving element. In this case, the electronic module 30 may be configured so that the light-receiving element receives light input from the first end face 111, the third end face 121, and the fifth end face 131. The light may also include electromagnetic waves other than visible light, such as infrared light, as long as the light has a wavelength that can be transmitted by the optical waveguide 10. Accordingly, the electronic element 31 may be a temperature-measuring element that measures temperature. The temperature-measuring element is, for example, a thermistor. Alternatively, the electronic element 31 may be, for example, a photodiode.

[0096] The lid 32 may be located above the package 20 for storing an electronic device. When the clad 14 has a recess 144 as shown in Fig. 1, the lid 32 may be located on the clad 14, covering the electronic device 31, so as to seal the inside of the recess 144. When the package 20 for storing an electronic device has a box 24 as shown in Figs. 7 and 8, the lid 32 may be located on the box 24, covering the electronic device 31.

[0097] The lid 32 may be flat, or may have a small recess corresponding to the protrusion 145. For example, when the top of the electronic element 31 is located higher than the top of the clad 14, the lid 32 may have a recess on its lower surface (the surface on the lower side in the Z direction).

[0098] The material of the lid 32 may be, for example, glass, silicon, or metal. Examples of glass include quartz, borosilicate, and sapphire. Examples of metal include aluminum, copper, iron, and alloys such as Fe-Ni-Co. When the lid 32 is made of metal, the lid 32 may have a plating layer on its surface. Examples of the material of the plating layer include gold and nickel.

[0099] A ring-shaped conductor may be positioned between the lid 32 and the package 20 for storing an electronic element. By joining the lid 32 and the package 20 for storing an electronic element with the conductor sandwiched between them, airtightness is improved compared to when they are directly joined with a resin-based adhesive.

[0100] As shown in FIG. 1 and other figures, lens 33 may be positioned in the direction in which light emitted from first side surface 141 is emitted. Lens 33 may be, for example, a convex lens, a diffractive lens, a rod lens, a ball lens, or the like. Lens 33 may be a member having a function of converting light emitted from each core into parallel light. Note that lens 33 does not necessarily have to be in contact with substrate 22.

[0101] [Electronic Devices] The display unit 41 may perform display using light emitted from the electronic module 30. The electronic device 40 may include the electronic module 30 and the display unit 41. The electronic device 40 may be, for example, AR glasses (Augmented Reality), a head-up display, a projector, or the like.

[0102] For example, when the electronic device 40 is an AR glass, the electronic device 40 may further include temples 42 and a control unit 43, as shown in FIG. 9 . In this case, the electronic module 30 may be located inside the temples 42. The temples 42 may be bendable or non-bendable. If the temples 42 are bendable, the electronic module 30 may not emit light when bent.

[0103] Display unit 41 may have a scanning mirror 411 and a light guiding unit 412. Scanning mirror 411 is, for example, a MEMS (Micro-Electro Mechanical Systems) mirror, and scans the light emitted from electronic module 30. The scanned light is input to a light guiding plate, a half mirror, or the like of light guiding unit 412. Scanning mirror 411 may be located inside temple 42.

[0104] As described above, light guide unit 412 may have a light guide plate or a half mirror, and may be able to project incident light onto the user's eyeball. Light guide unit 412 may be optically transparent. For example, light guide unit 412 may be a waveguide type, a half mirror type, or the like, allowing the user to view the projected image by superimposing it on the actual image transmitted through display unit 41. In the case of a half mirror type, light guide unit 412, which is a half mirror, may be separated from the glass surface. Light guide unit 412 may be transparent, or may be colored to block part of the transmitted light.

[0105] The projection image data is not particularly limited, but may be received from the outside via wireless communication or the like, or may be generated by the control unit 43 based on measurement results of a sensor provided in the AR glasses or the like. In addition, these types of image data may be used in combination.

[0106] The control unit 43 has, for example, a CPU, RAM, non-volatile memory, etc., and performs control processing related to image display. In addition to the above, the control unit 43 may also have an LD driver for controlling the LD, a MEMS driver for scanning and controlling the MEMS mirror, etc. The control unit 43 may be located inside or on the side of the temple 42, or may be located externally via a cable.

[0107] The glass surface including the light guide section 412 may be separate on the left and right as shown in Figure 9, or may be a single glass surface. The glass surface may have a large curved surface, particularly in the case of a half mirror system.

[0108] The electronic device 40, which is an AR glass, may be a head-mounted display having a band, a support, etc. for wearing on a person's head instead of the temples 42.

[0109] The electronic device 40 may also have a communication unit, a battery, etc. When the electronic device 40 is an AR glass, the communication unit, the battery, etc. may be located inside or on the side of the temple 42, or may be located outside via a cable.

[0110] In addition, the details shown in the above embodiments can be modified as appropriate without departing from the spirit of the present disclosure. The scope of the present invention includes the scope of the invention described in the claims and its equivalents. Various combinations of the embodiments are not limited to the examples of the above embodiments. Furthermore, combinations of the embodiments with each other are also possible. [Explanation of symbols]

[0111] 10 Optical waveguide 11 First Core 111 First end face 112 1st straight section 113 Location 1 114 Junction 115 Part 1 116 4th straight line section 117 Second end face 12 Second Core 121 3rd end face 122 2nd straight section 123 Second Location 124 First curved section 125 First Arc 126 Second Arc 127 5th straight line section 128 4th end face 13 Third Core 131 5th end face 132 3rd straight section 133 Third Location 134 Second curved section 135 Third Arc 136 Fourth Arc 137 6th straight line section 138 6th end face 14 Clad 141 First aspect 142 Optical waveguide section 143 Wall 144 recess 145 Protrusion 20. Electronic element housing package 21 electrodes 211 1st electrode 212 2nd electrode 213 3rd electrode 22 PCB 23 Element mounting area 24 Box body 241 Window 30 Electronic Module 31 Electronic elements 311 First Electronic Element 312 Second electronic element 313 Third Electronic Element 32 Lid 33 Lens 34 Bonding Wire 40 Electronic Devices 41 Display section 411 Scanning Mirror 412 Light guide section 42 Vine 43 Control Unit

Claims

1. a cladding having a first side; a first core located within the cladding and having a first end surface exposed to the first side surface and a plurality of second end surfaces; a second core located in the cladding and spaced apart from the first core, the second core having a third end surface exposed to the first side surface and a fourth end surface, the first core has a first linear portion, a junction portion, and a plurality of first portions, the number of which is the same as the number of the second end faces; the first linear portion includes the first end surface and has a constant width; the joining portion is connected to the first straight portion, and the joining portion has a width that decreases as it approaches the first straight portion, each of the first portions is connected to the junction portion and includes one of the second end surfaces; the second core has a second straight portion and a first curved portion, the second linear portion includes the third end surface and has a constant width, the first curved portion is connected to the second straight portion and has a curved shape, and the distance between the first curved portion and the first core decreases as the first curved portion approaches the second straight portion, When a boundary between the first straight line portion and the confluence portion is defined as a first point and a boundary between the second straight line portion and the first curved portion is defined as a second point, in a first direction in which the first straight line portion extends, a distance from the first end face to the first point is greater than a distance from the first end face to the second point. optical waveguide.

2. The first portions are spaced apart from one another at positions where they connect with the junction.

2. The optical waveguide according to claim 1.

3. At a position where the first portions are connected to the joining portion, a distance between the plurality of first portions is smaller than a distance between the first core and the second core.

3. The optical waveguide according to claim 2.

4. The width of the first linear portion is smaller than the width of the second linear portion.

2. The optical waveguide according to claim 1.

5. the maximum width of the joining portion is greater than the maximum width of the second core; 2. The optical waveguide according to claim 1.

6. In a side view taken along the width direction of the first straight portion, the entire joining portion overlaps with the first curved portion.

2. The optical waveguide according to claim 1.

7. The first core allows red light to enter.

2. The optical waveguide according to claim 1.

8. The area of ​​the first end face is smaller than the area of ​​any of the second end faces.

2. The optical waveguide according to claim 1.

9. The area of ​​each of the second end faces is larger than the area of ​​the fourth end face.

2. The optical waveguide according to claim 1.

10. a normal direction of the first end face is the same as a normal direction of the third end face, a distance between a center position of the first end surface and a center position of the third end surface is 1 to 10 μm; 2. The optical waveguide according to claim 1.

11. a path length from any of the second end faces to the first end face is shorter than a path length from the fourth end face to the third end face; 2. The optical waveguide according to claim 1.

12. a third core located in the cladding on the opposite side of the first core from the second core and spaced apart from the first core, the third core having a fifth end face exposed at the first side surface and a sixth end face; the third core has a third straight portion and a second curved portion, the third linear portion includes the fifth end surface and has a constant width, the second curved portion is connected to the third straight portion and has a curved shape, and the distance between the second curved portion and the first core decreases as the second curved portion approaches the third straight portion, When a boundary between the third straight portion and the second curved portion is defined as a third point, a distance from the first end surface to the first point in the first direction is greater than a distance from the first end surface to the third point.

2. The optical waveguide according to claim 1.

13. A substrate; an optical waveguide according to any one of claims 1 to 12 located on the substrate; an electrode located in an element mounting area above the substrate; the cladding has a recess in which the element mounting region is located, the second end surface and the fourth end surface are exposed in the recess. A package for storing electronic elements.

14. The electronic element storage package according to claim 13; an electronic element located in the element mounting area; a lid located on the cladding and covering the element mounting area, the electrodes include a first electrode and a second electrode; The electronic element includes a first electronic element connected to the first electrode and a second electronic element connected to the second electrode. Electronic module.

15. an electronic module according to claim 14; a display unit, the electronic element is a light-emitting element, the display unit performs display using light emitted from the electronic module. Electronic devices.

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