Light-emitting module
The light emitting module addresses the challenge of narrowing the irradiation area of multiple light sources by utilizing semiconductor laser elements and optical units with reflective members to control and focus the light emissions.
Patent Information
- Application Number
- JP2024221836
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2021-02-25
- Filing Date
- 2024-12-18
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2041-10-20
AI Technical Summary
Existing techniques struggle to effectively narrow the overall irradiation area of multiple light sources emitted from different locations.
The light emitting module incorporates multiple semiconductor laser elements, light emitting devices, and optical units with reflective members to control and narrow the irradiation area by adjusting the distances and angles of the laser beams.
This configuration allows for a significant reduction in the overall irradiation area, enabling the creation of a light emitting module that generates focused, narrowed light emissions.
Smart Images

Figure 2025038147000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a light emitting module. [Background technology]
[0002] There is an optical control technology that obtains desired light by irradiating light emitted from a light-emitting element onto multiple optical surfaces that provide optical effects such as reflection and refraction. Patent Document 1 discloses a technology that uses optical members such as a prism and a lens to control the beam width of laser light to a desired size. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Patent Publication No. 2013-179247 Summary of the Invention [Problem to be solved by the invention]
[0004] A technique is disclosed that, when a plurality of light beams emitted from a plurality of emission positions are used, can narrow the overall illumination area of the plurality of light beams. [Means for solving the problem]
[0005] A light emitting module according to an embodiment includes a first light emitting device having a plurality of first semiconductor laser elements each emitting a first laser beam, the first light emitting device emitting the plurality of first laser beams at intervals of a first distance in a slow axis direction of the first laser beams, a second light emitting device having a plurality of second semiconductor laser elements each emitting a second laser beam, the second light emitting device emitting the plurality of second laser beams at intervals of a second distance in the slow axis direction of the second laser beams, the second light emitting device being arranged side by side with the first light emitting device in a fast axis direction, and one or a plurality of first reflecting members providing a plurality of reflecting surfaces onto which the plurality of first laser beams and the plurality of second laser beams are incident, the interval between the plurality of first laser beams arranged in the slow axis direction being smaller than the first distance, and the plurality of second laser beams arranged in the slow axis direction being smaller than the first distance. a first optical unit that emits the plurality of first laser beams and the plurality of second laser beams with an interval between the second laser beams made smaller than the second distance; a second optical unit that has a plurality of second reflecting members that provide a plurality of reflecting surfaces onto which the plurality of first laser beams and the plurality of second laser beams are incident, and that reflects the first laser beam and the second laser beam emitted from the second light-emitting device at a third distance in a fast axis direction from the first laser beam at least two times, and emits them at an interval smaller than the third distance and with a narrow width in the fast axis direction of each laser beam; and a focusing lens that focuses the plurality of first laser beams and the plurality of second laser beams that have passed through the first optical unit and the second optical unit. Effect of the Invention
[0006] According to the present invention, the overall irradiation area of a plurality of light beams can be narrowed, and for example, a light emitting module that generates output light by utilizing the narrowed plurality of light beams can be realized. [Brief description of the drawings]
[0007] [Figure 1] FIG. 1 is a perspective view of a light-emitting module according to an embodiment. [Diagram 2] FIG. 2 is a perspective view for explaining each component arranged inside a housing of the light emitting module according to the embodiment. [Diagram 3]FIG. 3 is a perspective view of the state in which the first optical unit is omitted from FIG. [Figure 4] FIG. 4 is a top view of the state in which the flexible wiring is omitted from FIG. [Diagram 5] FIG. 5 is a cross-sectional view taken along line VV of FIG. [Figure 6] FIG. 6 is a schematic diagram showing the optical action of the first optical unit. [Figure 7] FIG. 7 is a schematic diagram showing the optical action of the second optical unit. [Figure 8] FIG. 8 is a perspective view of the light emitting device according to the embodiment. [Figure 9] FIG. 9 is a perspective view for explaining each component disposed inside the light emitting device according to the embodiment. [Figure 10] FIG. 10 is a top view of the light emitting device according to the embodiment. [Figure 11] FIG. 11 is a perspective view of a first reflecting member according to the embodiment. [Figure 12] FIG. 12 is a perspective view of the light-emitting unit according to the embodiment. [Figure 13] FIG. 13 is a schematic diagram for explaining the first light emitting width, the second light emitting width, the first center-to-center distance, the second center-to-center distance, the first outer edge distance, and the second outer edge distance according to the embodiment. [Figure 14] FIG. 14 is a diagram showing an example of a simulation result of the light emitting module according to the embodiment. [Figure 15] FIG. 15 is a diagram showing another example of the simulation result of the light emitting module according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] In this specification and claims, polygons such as triangles and quadrangles are referred to as polygons, including shapes in which the corners of the polygon have been rounded, chamfered, corner-removed, rounded, etc. Shapes in which processing has been applied to the middle part of the side, not just the corners (edges), are also referred to as polygons. In other words, shapes in which partial processing has been applied while leaving the polygon as the base are included in the interpretation of "polygon" described in this specification and claims.
[0009] This is not limited to polygons, but also applies to words that express specific shapes such as trapezoids, circles, and irregular shapes. The same is true when dealing with each side that forms the shape. In other words, even if the corners or middle part of a side have been processed, the interpretation of "side" includes the processed part. Note that when distinguishing a "polygon" or "side" that has no processing from a processed shape, the word "strict" is added, for example, "strict quadrangle."
[0010] In this specification or the claims, descriptions such as up and down, left and right, front and back, front and back, front and back, etc. merely describe relationships such as relative positions, orientations, and directions, and do not necessarily correspond to the relationships during use.
[0011] In the drawings, directions such as X-direction, Y-direction, and Z-direction may be indicated using arrows, and the directions of the arrows are consistent among multiple drawings relating to the same embodiment.
[0012] In this specification, for example, when explaining components, the terms "component" or "part" may be used. A "component" refers to an object that is physically handled as a single unit. An object that is physically handled as a single unit can also be said to be an object that is handled as a single part in the manufacturing process. On the other hand, a "part" refers to an object that does not need to be physically handled as a single unit. For example, a "part" is used when referring to a portion of a single component.
[0013] The distinction between "component" and "part" above does not indicate any intention to consciously limit the scope of the right in the interpretation of the doctrine of equivalents. In other words, even if there is a component described as a "component" in the claims, this does not mean that the applicant recognizes that treating this component as a single physical unit is essential for the application of the present invention.
[0014] In this specification or claims, when there are multiple elements and each element is to be expressed separately, the elements may be distinguished by adding "first" or "second" to the beginning of the element. The objects to be distinguished may be different between this specification and the claims. Therefore, even if the claims describe an element with the same notation as this specification, the object identified by this element may not be the same between this specification and the claims.
[0015] For example, if there are elements in this specification that are distinguished by the notation "first," "second," and "third," and the elements to which "first" and "third" are attached in this specification are described in the claims, the elements may be distinguished by the notation "first" and "second" in the claims from the viewpoint of readability. In this case, the elements to which "first" and "second" are attached in the claims refer to the elements to which "first" and "third" are attached in this specification, respectively. Note that this rule is not limited to elements, and can be applied rationally and flexibly to other objects as well.
[0016] Hereinafter, the embodiment of the present invention will be described. A specific embodiment of the present invention will be described with reference to the drawings. The embodiment of the present invention is not limited to this specific embodiment. In other words, the illustrated embodiment is not the only embodiment in which the present invention can be realized. The size and positional relationship of the members shown in each drawing may be exaggerated for ease of understanding.
[0017] <Embodiment> A light emitting module 1 according to an embodiment will be described. FIGS. 1 to 13 are diagrams for explaining an exemplary embodiment of the light emitting module 1. FIG. 1 is a perspective view of the light emitting module 1. FIG. 2 is a perspective view for explaining a plurality of components arranged in a space inside a housing 10 of the light emitting module 1. FIG. 3 is a perspective view of a state in which the first optical unit 30A is further omitted from the state of FIG. 2. FIG. 4 is a top view of a state in which the flexible wiring 2B is further omitted from the state of FIG. 2. FIG. 5 is a cross-sectional view taken along the VV cross-sectional line of FIG. 4. FIG. 6 is a schematic diagram for explaining an optical action of the first optical unit 30A. FIG. 6 is based on the cross-sectional view of FIG. 5, but the optical path is shown by hatching, and the hatching showing the cross section in FIG. 5 has been omitted for ease of viewing. FIG. 7 is a schematic diagram for explaining an optical action of the second optical unit 30B. The optical path is shown by hatching. FIG. 8 is a perspective view of the light emitting device 20. FIG. 9 is a perspective view for explaining each component arranged inside the light emitting device. FIG. 10 is a top view of the light emitting device 20. The irradiation area of the light emitted from the light emitting device 20 is indicated by hatching. FIG. 11 is a perspective view of the first reflecting member 31. FIG. 12 is a perspective view of the light emitting unit 2. FIG. 13 is a schematic diagram showing each parameter of the first light emitting width, the second light emitting width, the first center distance, the second center distance, the first outer edge distance, and the second outer edge distance described in the following embodiment. The hatching indicates the same irradiation area as in FIG. 10, and the center point of this irradiation area is also shown as necessary.
[0018] The light emitting module 1 includes a plurality of components. The plurality of components include a housing 10, one or more light emitting devices 20, one or more optical units 30, a condenser lens 40, and an optical fiber 50.
[0019] The light emitting module 1 may include a plurality of light emitting devices 20 including a first light emitting device 20A and a second light emitting device 20B. The light emitting module 1 may include a plurality of optical units 30 including a first optical unit 30A and a second optical unit 30B.
[0020] The light-emitting module 1 may include other components. For example, the light-emitting module 1 may include another light-emitting device in addition to the multiple light-emitting devices 20. The light-emitting module 1 may not include some of the components listed here.
[0021] First, each component will be described. (Chassis 10) The housing 10 has a space (hereinafter referred to as the arrangement space) provided therein for arranging other components. In other words, the housing 10 can be said to be a component that defines the arrangement space. It is preferable that the housing 10 has a structure that prevents gas from outside the housing from easily entering the arrangement space. For example, the housing 10 may be formed so that the arrangement space is an enclosed space.
[0022] The housing 10 has a mounting surface for mounting other components, one or more side surfaces surrounding the mounting surface, and a first surface located above the mounting surface and facing the mounting surface. The housing 10 has a light emitting section 12 that can transmit light from the arrangement space to the outside of the housing 10.
[0023] The housing 10 defines an arrangement space whose maximum length in a first direction is greater than the maximum length in a second direction perpendicular to the first direction in a top view. In the illustrated light-emitting module 1, the first direction is equal to the X direction, and the second direction is equal to the Y direction.
[0024] The housing 10 can be formed using an aluminum alloy as the main material. For example, the housing 10 can be formed using a zinc alloy, a magnesium alloy, a copper alloy, or the like as the main material. The main material refers to a material that occupies the largest proportion of the weight or volume of the target formation. When the target formation is formed from one material, that material is the main material. In other words, when a certain material is the main material, it includes the possibility that the proportion of that material can be 100%.
[0025] (Light emitting device 20) The light emitting device 20 includes one or more components including at least a light emitting element 21. The light emitting device 20 can include multiple components including one or more light emitting elements 21, a package 22, one or more submounts 25, one or more reflecting members 26, and one or more lens members 27.
[0026] The light emitting device 20 may include other components. For example, the light emitting device 20 may include further light emitting elements in addition to the plurality of light emitting elements 21. The light emitting device 20 may not include some of the components listed here.
[0027] In the illustrated light emitting module 1, the long side of the package 22 is aligned in the Y direction, and the short side of the package 22 is aligned in the X direction.
[0028] A space for arranging other components of the light emitting device 20 is provided inside the package 22. This space may be a sealed space. The package 22 may be composed of, for example, a light-shielding base member 23 that forms a recess, and a light-transmitting cover member 24 that covers the recess.
[0029] One or more light emitting elements 21 are disposed in the space inside the package 22. One or more reflective members 26 are disposed in this space. One or more submounts 25 are disposed in this space. The one or more light emitting elements 21 are mounted on the one or more submounts 25.
[0030] A semiconductor laser element can be used as the light emitting element 21. The light emitting element 21 is not limited to a semiconductor laser element, and may be a light emitting diode or the like. When a semiconductor laser element is used as the light emitting element 21, it is preferable that the space inside the package 22 is sealed in an airtight state. This makes it possible to suppress deterioration of the quality of light due to dust collection.
[0031] The light emitting element 21 is disposed on a mounting surface of the package 22 (hereinafter, the mounting surface of the housing is referred to as a first mounting surface, and the mounting surface of the package 22 is referred to as a second mounting surface to distinguish them), and emits light laterally. A light emission surface of the light emitting element 21 is provided on a side surface of the light emitting element 21. The light emission surface is not limited to the side surface of the light emitting element 21, and may be provided on the top surface, for example.
[0032] The light emitted from the emission surface of the light emitting element 21 is irradiated onto the reflection surface of the reflection member 26. The light reflected by the reflection member 26 travels upward and is emitted to the outside of the package 22. The light emitted to the outside of the package 22 passes through the lens member 27 and is emitted to the outside of the light emitting device 20.
[0033] For example, a light emitting element that emits blue light, a light emitting element that emits green light, or a light emitting element that emits red light can be used as the light emitting element 21. A light emitting element that emits light of another color may also be used as the light emitting element 21.
[0034] Blue light refers to light whose emission peak wavelength is in the range of 420nm to 494nm. Green light refers to light whose emission peak wavelength is in the range of 495nm to 570nm. Red light refers to light whose emission peak wavelength is in the range of 605nm to 750nm.
[0035] The one or more lens members 27 are disposed above the package 22. The one or more lens members 27 are fixed to the package 22. The one or more lens members 27 provide one or more lens surfaces.
[0036] The light that passes through the one or more lens members 27 is output as collimated light. The lens surfaces are designed so that the light that enters the lens member 27 is collimated. Collimated light is output from each lens surface provided by the one or more lens members 27.
[0037] The light emitting device 20 emits a plurality of beams of light. These beams are emitted from the light emitting device 20 in a predetermined direction at intervals of a predetermined distance. A plurality of collimated beams of light are emitted from the light emitting device 20. The light emitting device 20 emits a plurality of beams of collimated light.
[0038] The light emitting device 20 emits a plurality of lights based on light emitted from one or a plurality of light emitting elements 21. Each of the plurality of lights may be light emitted from a different light emitting element 21. The light emitting device 20 may include three or more light emitting elements 21.
[0039] Here, on a plane perpendicular to the light traveling direction, an illumination region having a first light-emitting width and a second light-emitting width perpendicular to the first light-emitting width is defined from the light emitted from the light-emitting device 20. The first light-emitting width is larger than the second light-emitting width. The maximum width of the light-emitting region on this plane can be defined as the first light-emitting width.
[0040] In the illustrated light emitting device 20, a plurality of light emitting elements 21 are arranged side by side. This light emitting device 20 includes four light emitting elements 21. Adjacent light emitting elements 21 are spaced apart by a predetermined distance. The plurality of light emitting elements 21 are arranged side by side at equal intervals. The direction in which the plurality of light emitting elements 21 are arranged is the same as the Y direction. All of the light emitting elements 21 are semiconductor laser elements.
[0041] In the illustrated light emitting device 20, a plurality of lights are emitted at a predetermined distance apart in the Y direction. A plurality of lights arranged at equal intervals are emitted from the light emitting device 20. The direction in which the plurality of lights are arranged is equal to the Y direction. The first light emitting width is equal to the X direction, and the second light emitting width is equal to the Y direction.
[0042] A semiconductor laser element, which is an example of the light emitting element 21, will be described. Light (laser light) emitted from the semiconductor laser element has a divergence. Diverging light is emitted from the emission end face of the semiconductor laser element. The emission end face of the semiconductor laser element can be said to be the light emission surface of the light emitting element 21.
[0043] The light emitted from a semiconductor laser element forms an elliptical far-field pattern (hereafter referred to as "FFP") in a plane parallel to the light emission facet. FFP refers to the shape and light intensity distribution of the emitted light at a position away from the emission facet.
[0044] The light passing through the center of the elliptical shape of the FFP, in other words, the light with the peak intensity in the light intensity distribution of the FFP, is called the light traveling along the optical axis or the light passing through the optical axis. Also, in the light intensity distribution of the FFP, the peak intensity value is 1 / e 2 The light having an intensity equal to or greater than this will be referred to as the main portion of the light.
[0045] The shape of the FFP of light emitted from a semiconductor laser element is an ellipse in which the stacking direction is longer than the direction perpendicular to the stacking direction on a plane parallel to the light emission end face. The stacking direction is the direction in which multiple semiconductor layers including the active layer are stacked in the semiconductor laser element. The direction perpendicular to the stacking direction can also be called the in-plane direction of the semiconductor layers. The long axis direction of the elliptical shape of the FFP can also be called the fast axis direction of the semiconductor laser element, and the short axis direction can also be called the slow axis direction of the semiconductor laser element.
[0046] Based on the light intensity distribution of FFP, the peak light intensity is 1 / e 2 The angle at which light with a light intensity of 1 / e spreads is defined as the spread angle of light from a semiconductor laser element. The spread angle of light is 1 / e 2 In addition to the light intensity at half the peak light intensity, the light intensity may also be calculated from the light intensity at half the peak light intensity. 2 The divergence angle of light in the fast axis direction is larger than the divergence angle in the slow axis direction.
[0047] Examples of semiconductor laser elements that emit blue light or green light include semiconductor laser elements that include nitride semiconductors. Examples of nitride semiconductors that can be used include GaN, InGaN, and AlGaN. Examples of semiconductor laser elements that emit red light include those that include InAlGaP, GaInP, GaAs, and AlGaAs semiconductors.
[0048] In the illustrated light emitting device 20, the fast axis direction of the laser light emitted from the light emitting device 20 is equal to the X direction, and the slow axis direction is equal to the Y direction. The multiple light beams emitted from the multiple light emitting elements 21 are emitted from the light emitting device 20 so that at least the main parts of the light do not overlap with each other. When the main parts of the light are prevented from overlapping in this way, arranging the beams in the slow axis direction can make the package 22 smaller than arranging the beams in the fast axis direction.
[0049] In the illustrated light emitting device 20, a laser light irradiation area can be defined from the main portion of the light. The first light emission width can be the width of the laser light in the fast axis direction of the main portion of the light, and the second light emission width can be the width of the laser light in the slow axis direction of the main portion of the light.
[0050] The illustrated light emitting device 20 includes a plurality of submounts 25 in a one-to-one relationship with the plurality of light emitting elements 21. The light emitting device 20 includes a plurality of reflecting members 26 in a one-to-one relationship with the plurality of light emitting elements 21. The light emitting device 20 includes one lens member 27 having the same number of lens surfaces as the plurality of light emitting elements 21.
[0051] In this light emitting device 20, a plurality of reflective members 26 are arranged in the same direction as the direction in which the plurality of light emitting elements 21 are arranged. A plurality of lens surfaces are arranged in the same direction as the direction in which the plurality of light emitting elements 21 are arranged. A plurality of light beams are emitted from the light emitting device 20 in a line. A plurality of light beams are arranged in the same direction as the direction in which the plurality of light emitting elements 21 are arranged, and are emitted from the light emitting device 20.
[0052] (First optical unit 30A) The first optical unit 30A has one or more reflecting members 31 (hereinafter referred to as first reflecting members 31). The one or more first reflecting members 31 provide a plurality of reflecting surfaces 31A. The plurality of reflecting surfaces 31A are not on the same plane and are parallel to each other. The plurality of reflecting surfaces 31A are provided on the same surface side of the first optical unit 30A. The plurality of reflecting surfaces 31A are provided at positions that do not overlap each other in a plan view seen from a direction perpendicular to a plane parallel to the reflecting surfaces 31A, but may partially overlap.
[0053] The first reflecting member 31 has a stepped outer shape, and a reflecting surface 31 A is formed on each of the successive steps. The first reflecting member 31 is a step-structure mirror in which a plurality of steps are formed, and a reflecting surface 31 A is provided on each step.
[0054] The multiple flat surfaces that form the steps in a staircase pattern in first reflecting member 31 are called step surfaces. It can be said that first reflecting member 31 includes multiple step surfaces that form the steps. If one of the consecutive steps is called the lower step and the other is called the upper step, the multiple step surfaces include at least the top surface of the lower step, the top surface of the upper step, and side surfaces that intersect with both top surfaces.
[0055] The top surface of a step surface is called the step top surface, and the side surface is called the step side surface. To form a step-like step, two or more step top surfaces and one or more step side surfaces are required. A step side surface intersects with both step top surfaces of consecutive steps. The step top surface and step side surface intersect each other perpendicularly, but they do not have to be perpendicular.
[0056] The first reflecting member 31 has a bottom surface located opposite the step top surface. The multiple step surfaces form a staircase shape based on the bottom surface. The first reflecting member 31 has an outer side surface that intersects with the step top surface on the opposite side of the step side surface that intersects with the step top surface of the top step, and an outer side surface that intersects with the step top surface on the opposite side of the step side surface that intersects with the step top surface of the bottom step. The multiple step surfaces are between these two outer sides.
[0057] A plurality of reflecting surfaces 31A are provided on the upper surfaces of a plurality of steps. A reflecting surface 31A is provided on each of the upper surfaces of the steps of successive steps. The reflecting surface 31A has a reflectance of 90% or more, preferably 95% or more, and more preferably 99% or more, for light of a specific wavelength. Although a higher reflectance of the reflecting surface 31A is preferable, it is a parameter that can be set appropriately as long as a sufficient amount of light to be used can be obtained. The above-mentioned numerical conditions for the reflectance are non-limiting conditions.
[0058] In a certain step surface, the direction along the direction in which the step is formed is referred to as the step direction. For example, in the illustrated light-emitting module 1, the direction perpendicular to the intersection line between the step top surface and the step side surface on a plane parallel to the step top surface is the step direction in the step top surface, and the direction perpendicular to the intersection line between the step top surface and the step side surface on a plane parallel to the step side surface is the step direction in the step top surface.
[0059] The length of the step top surface in the step direction is greater than the length of the step side surface intersecting with the step top surface in the step direction. The length of the step top surface in the step direction is three times or more the length of the step side surface intersecting with the step top surface in the step direction.
[0060] (Second optical unit 30B) The second optical unit 30B has a plurality of reflecting members 32 (hereinafter referred to as second reflecting members 32). The plurality of second reflecting members 32 provide a plurality of reflecting surfaces 33. The plurality of reflecting surfaces 33 includes one or a plurality of first reflecting surfaces 33A and one or a plurality of second reflecting surfaces 33B. The surface shapes of the first reflecting surface 33A and the second reflecting surface 33B are different curved surfaces.
[0061] The multiple second reflecting members 32 include a reflecting member 32A having a first reflecting surface 33A and a reflecting member 32B having a second reflecting surface 33B. The multiple second reflecting members 32 may include a second reflecting member 32 having two or more reflecting surfaces 33. The multiple second reflecting members 32 may include a second reflecting member 32 having only one reflecting surface 33.
[0062] For example, the first reflecting surface 33A is formed in a cylindrical concave shape, and the second reflecting surface 33B is formed in a cylindrical convex shape. The second reflecting members 32 include a concave cylindrical mirror having the first reflecting surface 33A and a convex cylindrical mirror having the second reflecting surface 33B.
[0063] In the illustrated light-emitting module 1, the second optical unit 30B is composed of three second reflecting members 32. Two second reflecting members 32 having a first reflecting surface 33A and one second reflecting member 32 having a second reflecting surface 33B. The two former second reflecting members 32 are both concave cylindrical mirrors, and the latter one second reflecting member 32 is a convex cylindrical mirror. The number of second reflecting members 32 having the first reflecting surface 33A is greater than the number of second reflecting members 32 having the second reflecting surface 33B.
[0064] (Condenser lens 40) The condenser lens 40 is a lens for collecting incident light to a predetermined point or area, and is, for example, a plano-convex lens.
[0065] (Optical fiber 50) The optical fiber 50 has a fiber connecting an input port and an output port. Light incident from the input port propagates inside the fiber and is output from the output port. The optical fiber 50 has, for example, a core diameter at the input port (hereinafter referred to as fiber diameter) of 400 μm or less. The fiber diameter can be in the range of 150 μm to 300 μm. Alternatively, the fiber diameter can be in the range of 150 μm to 250 μm. An even smaller fiber diameter is also possible.
[0066] (Light Emitting Module 1) Next, the light emitting module 1 will be described. In the light emitting module 1, one or more light emitting devices 20 are arranged in the arrangement space of the housing 10. The one or more light emitting devices 20 are arranged on a mounting surface. The light emitting device 20 is arranged such that the lens member 27 faces the first surface side of the housing 10. A plurality of light beams are emitted upward from the light emitting device 20.
[0067] Four light-emitting elements 21 arranged in two rows and two columns are arranged in the arrangement space of the housing 10. The arrangement is not limited to two rows and two columns, and may be, for example, three rows and two columns, or three rows and three columns. The light-emitting elements 21 may be arranged in N rows and M columns (N≧2 and M≧2, and N and M are both natural numbers) on the mounting surface. In the illustrated light-emitting module 1, eight light-emitting elements 21 are arranged in four rows and two columns.
[0068] In the arrangement space of the housing 10, four lights arranged in two rows and two columns are emitted from one or more light emitting devices 20 toward a predetermined direction (for example, upward). The arrangement is not limited to two rows and two columns, but may be, for example, three rows and two columns or three rows and three columns. The multiple lights are arranged in N rows and M columns (N≧2 and M≧2, N and M are both natural numbers) and travel in a predetermined direction. The four lights do not have to travel in the same direction. For example, they can travel upward while approaching or moving away from each other. It is preferable that the traveling direction of the four lights is symmetrical. In the illustrated light emitting module 1, eight lights arranged in four rows and two columns travel upward in the Z direction.
[0069] In the illustrated light-emitting module 1, a plurality of light-emitting elements 21 are arranged so that the row direction is equal to the X direction, and a plurality of light-emitting elements 21 are arranged so that the column direction is equal to the Y direction.
[0070] When defining the distance between two adjacent lights, the distance between the centers and the distance between the outer edges can be considered. The distance between the centers of two adjacent lights can be calculated by taking the midpoint of the first light emission width as the center of the light. The distance between the centers of two adjacent lights can also be calculated by taking the midpoint of the second light emission width as the center of the light. The distance between the outer edges can be calculated based on the outer edges of the irradiation areas of each light. If there is an overlap between the irradiation areas of the two adjacent lights, the distance between the outer edges is zero.
[0071] The center-to-center distance based on the first light-emitting width is referred to as the first center-to-center distance, the center-to-center distance based on the second light-emitting width is referred to as the second center-to-center distance, the outer edge distance based on the first light-emitting width is referred to as the first outer edge distance, and the outer edge distance based on the second light-emitting width is referred to as the second outer edge distance.
[0072] In the illustrated light-emitting module 1, the center-to-center distance in the row direction is equal to the first center-to-center distance, the center-to-center distance in the column direction is equal to the second center-to-center distance, the outer edge distance in the row direction is equal to the first outer edge distance, and the outer edge distance in the column direction is equal to the second outer edge distance. In Fig. 13, the first light-emitting width, the second light-emitting width, the first center-to-center distance, the second center-to-center distance, the first outer edge distance, and the second outer edge distance are illustrated by the symbols W1, W2, C1, C2, E1, and E2, respectively.
[0073] The multiple light beams emitted from the one or more light emitting devices 20 have different first and second center distances at the emission points from the one or more light emitting devices 20. At the emission points, the first center distance is longer than the second center distance. These distances may be the same.
[0074] At this emission point, the first center distance is greater than the first emission width of either of the two adjacent beams of light. At this emission point, the second center distance is greater than the second emission width of either of the two adjacent beams of light. In other words, it can be said that there is a gap between the two adjacent beams of light. In other words, it can be said that both the first outer edge distance and the second outer edge distance are greater than 0.
[0075] In the illustrated light-emitting module 1, a plurality of light-emitting devices 20 are arranged. The plurality of light-emitting devices 20 include a first light-emitting device 20A and a second light-emitting device 20B arranged side by side. The first light-emitting device 20A and the second light-emitting device 20B are arranged side by side in the row direction. A plurality of light-emitting elements 21 included in the light-emitting device 20 are arranged side by side in the column direction. The direction in which the first light-emitting device and the second light-emitting device are arranged is the same as the X direction. The direction in which the plurality of light-emitting elements 21 included in the light-emitting device 20 are arranged is the same as the Y direction.
[0076] In the illustrated light-emitting module 1, the multiple light-emitting elements 21 (hereinafter referred to as first light-emitting elements) of the first light-emitting device 20A and the multiple light-emitting elements 21 (hereinafter referred to as second light-emitting elements) of the second light-emitting device 20B are arranged with equal spacing (first outer edge distance) in each row. The spacing (second outer edge distance) of the multiple first light-emitting elements is the same as the spacing (second outer edge distance) of the multiple second light-emitting elements. These spacings do not have to be the same.
[0077] 12, for example, if a light-emitting unit 2 in which a first light-emitting device 20A and a second light-emitting device 20B are mounted on one wiring board is manufactured, mounting of the light-emitting module 1 can be facilitated. The illustrated light-emitting unit 2 further includes a wiring connector 2A, so that power can be collectively supplied to the two light-emitting devices 20 from the wiring connector 2A. In the illustrated light-emitting module 1, a flexible wiring 2B is connected to the wiring connector 2A.
[0078] In the illustrated light-emitting module 1, the light emitted from the multiple light-emitting elements 21 has its optical axis parallel to each other and is emitted upward from one or more light-emitting devices 20. Here, "parallel" includes a difference of ±2 degrees or less. The traveling direction of the multiple collimated light beams emitted from the one or more light-emitting devices 20 is the same as the Z direction.
[0079] In the light emitting module 1, a first optical unit 30A is disposed in the arrangement space of the housing 10. The first optical unit 30A is disposed above one or more light emitting devices 20. Light emitted from the light emitting devices 20 is irradiated onto the first optical unit 30A. The light emitted from the light emitting devices 20 is reflected by a reflecting surface 31A of the first optical unit 30A.
[0080] In the light emitting module 1, a plurality of light beams emitted from one or a plurality of light emitting devices 20 are irradiated onto a plurality of reflective surfaces 31A and are reflected by the plurality of reflective surfaces 31A. The plurality of reflective surfaces 31A have the reflectance characteristics for the light beams emitted from the one or a plurality of light emitting devices 20 as described above for the first optical unit 30A.
[0081] In top view, the centers of the second light emission widths of the multiple light beams aligned in the column direction overlap with different reflecting surfaces 31A. In top view, the centers of the second light emission widths of the multiple light beams aligned in the column direction overlap with different reflecting surfaces 31A. The multiple light beams aligned in the column direction are each irradiated onto a different reflecting surface 31A.
[0082] In top view, the centers of the first light-emitting widths of the multiple light beams aligned in the row direction overlap with the same reflecting surface 31A. In top view, the centers of the first light-emitting widths of the multiple light beams aligned in the row direction overlap with the same reflecting surface 31A. In the illustrated light-emitting module 1, for each of the multiple light beams, a major portion of the light is irradiated onto one of the multiple reflecting surfaces 31A and is not irradiated onto the other reflecting surfaces 31A.
[0083] The reflecting surface 31A is disposed at an angle with respect to the mounting surface. The reflecting surfaces 31A are arranged in a row in a top view. The reflecting surfaces 31A arranged in a row are disposed higher from the reflecting surface 31A at one end toward the reflecting surface 31A at the other end.
[0084] A plurality of light beams emitted from one light emitting device 20 are irradiated onto one first reflecting member 31. The first reflecting member 31 has reflecting surfaces 31A equal in number to or greater than the number of light beams emitted from the light emitting device 20. Associating one first reflecting member 31 with one light emitting device 20 facilitates mounting.
[0085] In the illustrated light-emitting module 1, the first optical unit 30A is configured with one first reflecting member 31. One first reflecting member 31 corresponds to two light-emitting devices 20. One first reflecting member 31 may correspond to one light-emitting device 20.
[0086] The first optical unit 30A emits a plurality of light beams reflected by a plurality of reflecting surfaces 31A. The light beams emitted from the first optical unit 30A travel in the column direction. A plurality of light beams aligned in the vertical direction are emitted from the first optical unit 30A. The plurality of light beams aligned in the vertical direction are a plurality of light beams aligned in the direction of the second light emission width.
[0087] In the illustrated light emitting module 1, the multiple light beams aligned in the second light emitting width are aligned in the Z direction and emitted from the first optical unit 30A. The multiple light beams emitted from the first optical unit 30A travel in the Y direction. All of the multiple light beams emitted from the first optical unit 30A remain collimated light beams.
[0088] The second outer edge distance of the multiple light beams aligned in the direction of the second light emission width emitted from the first optical unit 30A is smaller than the second outer edge distance of the multiple light beams aligned in the direction of the second light emission width at the emission points emitted from one or more light emitting devices 20. In other words, the multiple light beams emitted from one or more light emitting devices 20 at intervals of a predetermined distance in the direction of the second light emission width are emitted from the first optical unit 30A with the intervals reduced. This makes it possible to narrow the overall irradiation area of the multiple light beams aligned in the direction of the second light emission width.
[0089] The first outer edge distance of the multiple beams of light aligned in the direction of the first light emission width emitted from the first optical unit 30A is the same as the first outer edge distance of the multiple beams of light aligned in the direction of the first light emission width at the emission points emitted from one or more light emitting devices 20. Therefore, it can also be said that the first optical unit 30A narrows the overall irradiation area of the multiple beams of light.
[0090] In the illustrated light-emitting module 1, multiple light beams emitted from the first light-emitting device 20A at a predetermined interval in the slow axis direction are emitted from the first optical unit 30A with the intervals reduced, and multiple light beams emitted from the second light-emitting device 20B at a predetermined interval in the slow axis direction are emitted from the first optical unit 30A with the intervals reduced.
[0091] In the illustrated light-emitting module 1, the first optical unit 30A has one or more first reflecting members 31 that provide a plurality of reflecting surfaces 31A on which the plurality of laser beams (hereinafter referred to as first lasers) emitted from the first light-emitting device 20A and the plurality of laser beams (hereinafter referred to as second laser beams) emitted from the second light-emitting device 20B are incident. The first optical unit 30A emits the plurality of first laser beams and the plurality of second laser beams from the first optical unit 30A by making the interval between the plurality of first laser beams aligned in the slow axis direction smaller than the distance when they are emitted from the first light-emitting device 20A and by making the interval between the plurality of second laser beams aligned in the slow axis direction smaller than the distance when they are emitted from the second light-emitting device 20B.
[0092] The second outer edge distance of the multiple lights aligned in the direction of the second light emission width emitted from the first optical unit 30A is 0 μm or more and less than 500 μm. This second outer edge distance is 300 μm or more smaller than the second outer edge distance at the emission points emitted from one or more light emitting devices 20. The second light emission width of the light emitted from the light emitting device 20 is preferably 250 μm or more and 500 μm or less. This makes it more effective to narrow the irradiation area of the multiple lights as a whole by narrowing the second outer edge distance.
[0093] In the light emitting module 1, the second optical unit 30B is disposed in the arrangement space of the housing 10. The second optical unit 30B is disposed above and to the side of one or more light emitting devices 20. Light emitted from the light emitting devices 20 is irradiated onto the second optical unit 30B. Light emitted from the first optical unit 30A is irradiated onto the second optical unit 30B. Light reflected by the reflecting surface 33 is emitted from the second optical unit 30B.
[0094] The light incident on the second optical unit 30B is reflected two or more times and then emitted from the second optical unit 30B. The light incident on the second optical unit 30B is irradiated to the first reflecting surface 33A, reflected by the first reflecting surface 33A, and then irradiated to the second reflecting surface 33B. The first reflecting surface 33A changes the light incident on the first reflecting surface 33A into converging light and reflects it. The reflected converging light travels toward the second reflecting surface 33B. The second reflecting surface 33B changes the light incident on the second reflecting surface 33B into collimated light and reflects it. The light collimated by the second reflecting surface 33B is emitted from the second optical unit 30B.
[0095] The first outer edge distance of the multiple light beams aligned in the direction of the first light emission width emitted from the second optical unit 30B is smaller than the first outer edge distance of the multiple light beams aligned in the direction of the first light emission width at the emission points emitted from one or more light emitting devices 20. In other words, the multiple light beams emitted from one or more light emitting devices 20 at intervals of a predetermined distance in the direction of the first light emission width are emitted from the second optical unit 30B with the intervals reduced. This makes it possible to narrow the overall irradiation area of the multiple light beams aligned in the direction of the first light emission width.
[0096] The first outer edge distance of the multiple light beams aligned in the direction of the first light emission width emitted from the second optical unit 30B is smaller than the first outer edge distance of the multiple light beams aligned in the direction of the first light emission width from the first optical unit 30A to entering the second optical unit 30B.
[0097] The first light emission width of the multiple light beams emitted from the second optical unit 30B is smaller than the first light emission width at the emission point from the one or more light emitting devices 20. In other words, the multiple light beams emitted from the one or more light emitting devices 20 are emitted from the second optical unit 30B with a smaller first light emission width. This makes it possible to narrow the overall irradiation area of the multiple light beams aligned in the direction of the first light emission width.
[0098] The second distance between the outer edges of the multiple light beams aligned in the direction of the second light emission width emitted from the second optical unit 30B is the same as the second distance between the outer edges of the multiple light beams aligned in the direction of the second light emission width emitted from the first optical unit 30A. Therefore, it can be said that the second optical unit 30B narrows the overall irradiation area of the multiple light beams.
[0099] In the illustrated light emitting module 1, a plurality of light beams that enter the first optical unit 30A and are emitted from the first optical unit 30A enter the second optical unit 30B. That is, the light beams enter the first optical unit 30A first, and then the second optical unit 30B. The light emitting module can also be designed so that the light beams enter the second optical unit 30B first, and then the first optical unit 30A.
[0100] In the illustrated light-emitting module 1, multiple light beams emitted from the first light-emitting device 20A and the second light-emitting device 20B at a predetermined interval in the fast axis direction are emitted from the second optical unit 30B with the interval and the width in the fast axis direction reduced.
[0101] In the illustrated light-emitting module 1, the second optical unit 30B has a plurality of second reflecting members 32 that provide a plurality of reflecting surfaces 33 onto which a plurality of first laser beams and a plurality of second laser beams are incident. The second optical unit 30B reflects the first laser beam and the second laser beam emitted from the second light-emitting device at a predetermined distance in the fast axis direction from the first laser beam at least twice, respectively, and emits them from the second optical unit 30B at intervals smaller than the predetermined distance and with a reduced width in the fast axis direction of each laser beam.
[0102] In the illustrated light-emitting module 1, a second reflecting member 32 having a first reflecting surface 33A that reflects a plurality of light beams emitted from a first light-emitting device 20A and a second reflecting member 32 having a first reflecting surface 33A that reflects a plurality of light beams emitted from a second light-emitting device 20B are arranged side by side. By using two second reflecting members 32, the position adjustment of the first reflecting surface 33A with respect to the plurality of light beams emitted from the first light-emitting device 20A and the position adjustment of the first reflecting surface 33A with respect to the plurality of light beams emitted from the second light-emitting device 20B can be performed separately, thereby improving accuracy.
[0103] In the illustrated light emitting module 1, one of the two second reflecting members 32 having a first reflecting surface 33A reflects the multiple light beams emitted from the first light emitting device 20A, but does not reflect the multiple light beams emitted from the second light emitting device 20B. The other second reflecting member 32 reflects the multiple light beams emitted from the second light emitting device 20B, but does not reflect the multiple light beams emitted from the first light emitting device 20A.
[0104] In the illustrated light emitting module 1, the second reflecting member 32 having the second reflecting surface 33B reflects the multiple light beams emitted from the first light emitting device 20A and also reflects the multiple light beams emitted from the second light emitting device 20B. Since the multiple converged light beams are incident on this second reflecting member 32, they can be easily reflected collectively by the single reflecting surface 33. Arranging separate second reflecting members 32 requires spacing, but with a single second reflecting member 32, the spacing between the light beams emitted from the first light emitting device 20A and the light beams emitted from the second light emitting device 20B can be made smaller than the spacing required when the light beams are arranged separately.
[0105] In the light emitting module 1, a condenser lens 40 is disposed in the arrangement space of the housing 10. A plurality of light beams that are incident on the first optical unit 30A and emitted from the first optical unit 30A and that are incident on the second optical unit 30B and emitted from the second optical unit 30B are incident on the condenser lens 40. The condenser lens 40 condenses the plurality of light beams that have passed through the first optical unit 30A and the second optical unit 30B.
[0106] In the light-emitting module 1, the optical fiber 50 is connected to the light emitting section 12 of the housing 10. The optical fiber 50 is attached to, for example, the output port of the housing 10. A plurality of light beams that have passed through the focusing lens 40 enter the optical fiber 50. A plurality of light beams focused by the focusing lens 40 enter the input port of the optical fiber 50. The light that enters the input port of the optical fiber 50 propagates through the fiber and is output from the output port.
[0107] In the light-emitting module 1, the multiple light beams collected by the collecting lens 40 are made incident on the optical fiber 50. Considering the intersection during actual manufacturing, the smaller the irradiation area of the entire multiple light beams incident on the collecting lens 40, the smaller the irradiation area at the entrance of the optical fiber 50 can be. By reducing the irradiation area of the entire multiple light beams by the first optical unit 30A and the second optical unit 30B, the fiber diameter at the entrance of the optical fiber 50 can be reduced.
[0108] FIG. 14 is a diagram showing an example of a result of simulating a plurality of lights irradiated to an entrance of an optical fiber 50 in the illustrated light-emitting module 1. The circle in the diagram can be assumed to be the fiber diameter at the entrance of the optical fiber 50. In this diagram, the result is obtained that eight lights can be collected and made incident on a fiber diameter of 207 μm. FIG. 15 shows a simulation result assuming a light-emitting module 1 with greater mounting variation than the light-emitting module 1 in FIG. 14. In this diagram, the result is obtained that eight lights can be collected and made incident on a fiber diameter of 242 μm. In the case of assuming an ideal light-emitting module 1, the result is obtained that the lights can be made incident on a fiber diameter of 169 μm.
[0109] Based on these simulation results, the light emitting module 1 according to the embodiment can make 6 to 12 light beams emitted from one or more light emitting devices 20 enter a fiber with a diameter of 150 μm to 300 μm. It can make 6 to 10 light beams emitted from one or more light emitting devices 20 enter a fiber with a diameter of 150 μm to 250 μm. By utilizing the technology disclosed in the light emitting module 1, it is possible to enter more light into a smaller fiber diameter without being limited to this condition.
[0110] Although the embodiments of the present invention have been described above, the light-emitting device of the present invention is not strictly limited to the light-emitting device of the embodiment. In other words, the present invention can be realized without being limited to the external shape and structure of the light-emitting device disclosed in the embodiment. It can be applied without necessarily having all the components. For example, if some of the components of the light-emitting device disclosed in the embodiment are not described in the claims, the freedom of design by those skilled in the art, such as substitution, omission, modification of the shape, and change of the material, is recognized for those some components, and the invention described in the claims is specified to be applied. [Industrial Applicability]
[0111] The light emitting device described in each embodiment can be used for lighting, projectors, vehicle headlights, head mounted displays, displays, and the like. [Explanation of symbols]
[0112] 1 Light emitting module 10. Chassis 12 Light emitting part 20 Light emitting device 20A First light emitting device 20B Second light emitting device 21 Light emitting element 22 Packages 23 Base member 24 Lid member 25 Submount 26 Reflective material 27 Lens parts 30 Optical Unit 30A First Optical Unit 31 First reflecting member 31A Reflective surface 30B Second optical unit 32 Second reflecting member 32A Reflective material 32B Reflective material 33 Reflective surface 33A 1st reflective surface 33B 2nd reflective surface 40 Condenser Lens 50 Optical Fiber 2 Light Emitting Unit 2A Wiring Connector 2B flexible wiring
Claims
1. a first light emitting device including a plurality of first semiconductor laser elements each emitting a first laser beam, the first semiconductor laser elements emitting the first laser beams at intervals of a first distance in a slow axis direction of the first laser beams; a second light emitting device including a plurality of second semiconductor laser elements each emitting a second laser beam, the second light emitting devices emitting the second laser beams at intervals of a second distance in a slow axis direction of the second laser beams, and arranged next to the first light emitting device in a fast axis direction; a first optical unit including one or more first reflecting members each having a plurality of reflecting surfaces onto which the plurality of first laser beams and the plurality of second laser beams are incident, the first optical unit emitting the plurality of first laser beams and the plurality of second laser beams while making an interval between the plurality of first laser beams aligned in the slow axis direction smaller than the first distance and making an interval between the plurality of second laser beams aligned in the slow axis direction smaller than the second distance; a second optical unit including a plurality of second reflecting members each having a plurality of reflecting surfaces on which the plurality of first laser beams and the plurality of second laser beams are incident, the second optical unit reflecting the first laser beams and the second laser beam emitted from the second light emitting device at a third distance from the first laser beam in a fast axis direction at least twice, respectively, and emitting the first laser beams and the second laser beams at an interval smaller than the third distance and with a narrower width in the fast axis direction of each laser beam; a focusing lens that focuses the first laser beams and the second laser beams that have passed through the first optical unit and the second optical unit; A light emitting module comprising:
2. The light-emitting module according to claim 1 , further comprising: an optical fiber into which the plurality of first laser beams and the plurality of second laser beams focused by the focusing lens are incident.
3. the plurality of first laser beams and the plurality of second laser beams are constituted by six or more laser beams in total, 3. The light emitting module according to claim 2, wherein a fiber diameter of the optical fiber into which the plurality of first laser beams and the plurality of second laser beams are incident is not less than 150 μm and not more than 300 μm.
4. the first optical unit is a stepped mirror having a plurality of steps, each step being provided with the reflecting surface; The light emitting module according to claim 1 , wherein the plurality of second reflecting members include a first concave cylindrical mirror and a convex cylindrical mirror.
5. the plurality of second reflecting members further include a second concave cylindrical mirror; the first concave cylindrical mirror reflects the first laser beams and does not reflect the second laser beams; the second concave cylindrical mirror reflects the second laser beams and does not reflect the first laser beams; The light emitting module according to claim 4 , wherein the plurality of first laser beams and the plurality of second laser beams are reflected by the convex cylindrical mirror.
6. The light emitting module according to claim 1 , wherein the first distance and the second distance are the same.
7. The light emitting module according to claim 1 , wherein the plurality of first laser beams and the plurality of second laser beams emitted from the first optical unit are incident on the second optical unit.
8. the first light emitting device emits the plurality of first laser beams as collimated beams; The light-emitting module according to claim 1 , wherein the second light-emitting device emits the plurality of second laser beams as collimated beams.
Citation Information
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