Light-emitting device

Abstract

Even a small change in the distance between the lens and the light source in the direction of light irradiation can alter the illumination range. [Solution] The light-emitting device 1 comprises a light-emitting element 10 that emits light from a light-emitting surface 11, and a lens 20 having an incident surface 21 into which the light emitted from the light-emitting element is incident and an outgoing surface 22 that emits light. The lens is movable a predetermined distance D relative to the light-emitting element in the direction of the center of luminosity of the light-emitting surface. The incident surface has a first region 211 formed on a substantially flat surface facing the center of luminosity, and a second region 212 provided around the first region where a plurality of reflective prisms 213 are formed. The ratio of the maximum width W2 of the first region to the maximum width W1 of the light-emitting surface is a predetermined ratio including equality.

Description

Technical Field

[0001] The present invention relates to a light-emitting device.

Background Art

[0002] As a light-emitting device mainly used for a flash of a camera device, there is known a light-irradiating device that expands or contracts an irradiation range of a lens with respect to an irradiated object by moving an irradiation lens support in the optical axis direction (for example, see Patent Document 1). [[ID=第十四条]]

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when the light-emitting device is provided in a mobile terminal device with a camera, it is required to reduce the height of the light-emitting device. For this reason, in the light-emitting device, in order to realize a wide irradiation range while reducing the height, it is required to shorten the moving distance of the irradiation lens in the central direction of the luminous intensity (optical axis direction).

[0005] Further, in the light-emitting device, when the irradiation lens is moved in the central direction of the luminous intensity to change the light irradiation range, high light uniformity is required.

[0006] The present invention takes the above problems as an example, and an object thereof is to provide a light-emitting device that can change an irradiation range even when the amount of change in the distance between a lens and a light source in the light irradiation direction is small.

Means for Solving the Problems

[0007] To achieve the above objective, the light-emitting device according to the present invention comprises a light-emitting element that emits light from a light-emitting surface, and a lens having an incident surface into which the light emitted from the light-emitting element is incident and an outgoing surface from which the light is emitted, wherein the lens is movable a predetermined distance relative to the light-emitting element in the direction of the center of luminosity of the light-emitting surface, the incident surface has a first region formed on a substantially flat surface facing the center of luminosity, and a second region provided around the first region where a plurality of reflective prisms are formed, and the ratio of the maximum width of the first region to the maximum width of the light-emitting surface is a predetermined ratio including the same. [Effects of the Invention]

[0008] According to the present invention, the light-emitting device makes it possible to change the irradiation range even if the amount of change in the distance between the lens and the light source in the direction of light irradiation is small. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic side view showing the configuration of a light-emitting device according to an embodiment of the present invention. [Figure 2] This figure shows the relationship between the simulation results of the illuminance distribution and a predetermined region when the distance from the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment is a first distance. [Figure 3] This figure shows the relationship between the simulation results of the illuminance distribution and a predetermined region when the distance from the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment is the second distance. [Figure 4] This is a side view showing the positional relationship between the light-emitting element and the lens when the distance between the light-emitting surface of the light-emitting element and the incident surface of the lens of the light-emitting device according to this embodiment is minimized. [Figure 5] This is a side view showing the positional relationship between the light-emitting element and the lens when the distance between the light-emitting surface of the light-emitting element and the incident surface of the lens of the light-emitting device according to this embodiment is at its maximum. [Figure 6] This figure shows the simulation results of the illuminance distribution when the distance between the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment and the incident surface of the lens is minimized. [Figure 7] This figure shows the simulation results of the illuminance distribution in the x-direction when the distance between the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment and the incident surface of the lens is minimized. [Figure 8] This figure shows the simulation results of the illuminance distribution in the y-direction when the distance between the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment and the incident surface of the lens is minimized. [Figure 9] This figure shows the simulation results of the illuminance distribution when the distance between the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment and the incident surface of the lens is at its maximum. [Figure 10] This figure shows the simulation results of the illuminance distribution in the x-direction when the distance between the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment and the incident surface of the lens is at its maximum. [Figure 11] This figure shows the simulation results of the illuminance distribution in the y-direction when the distance between the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment and the incident surface of the lens is at its maximum. [Figure 12] This graph shows the relationship between the ratio of the maximum width of the first region of the lens to the maximum width of the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment, and uniformity or illuminance. [Figure 13] This graph shows the relationship between the ratio of the maximum width of the first region of the lens to the maximum width of the light-emitting surface of the light-emitting element of the light-emitting device according to this embodiment, and the gain of the central illuminance. [Figure 14] This is a schematic side view showing the configuration of a light-emitting device according to a modified example of the present invention. [Modes for carrying out the invention]

[0010] 1. Overview of the Embodiment First, a general overview of a typical embodiment of the invention disclosed in this application will be provided. In the following description, reference numerals in the drawings corresponding to the components of the invention are indicated in parentheses as an example.

[0011] [1] A light-emitting device including a light-emitting element (10) that emits light (L1, L21, L22) from a light-emitting surface (11), and a lens (20) having an incident surface (21) on which the light emitted from the light-emitting element is incident and an exit surface (22) that emits the light. The lens is movable relative to the light-emitting element by a predetermined moving distance (D) in the central direction of the luminous intensity of the light-emitting surface. The incident surface has a first region (211) formed as a substantially flat surface facing the center of the luminous intensity, and a second region (212) provided around the first region and having a plurality of reflection prisms (213) formed thereon. The ratio of the maximum width (W2) of the first region to the maximum width (W1) of the light-emitting surface is a predetermined ratio including equality.

[0012] [2] The ratio of the maximum width of the first region to the maximum width of the light-emitting surface is 0.2 to 1.5. The light-emitting device according to [1].

[0013] [3] The distance between the light-emitting surface and the incident surface is 0.1 to 1.0 mm. The light-emitting device according to [1] or [2].

[0014] [4] At least one of a prism, a microlens, or a texturing is provided in the first region. The light-emitting device according to [1] to [3].

[0015] [5] The angle of the inclined surface of the reflection prism is 30° or more. The light-emitting device according to [1] to [4].

[0016] [6] The ratio of the central illuminance of the light emitted from the lens when the distance between the light-emitting surface and the incident surface is minimum to the central illuminance of the light emitted from the lens when the distance between the light-emitting surface and the incident surface is maximum is 2.0 to 5.0. The light-emitting device according to [1] to [5]. described light-emitting device.

[0017] [7] The light-emitting element is provided on the upper surface (31) of a substrate (30), and a support portion (23) protruding toward the upper surface is provided on the incident surface. The light-emitting device according to [1] to [6].

[0018] 2. Specific Examples of Embodiments Hereinafter, a light-emitting device 1 according to an embodiment of the present invention will be described with reference to the drawings.

[0019] Figure 1 is a schematic side view showing the configuration of a light-emitting device 1 according to an embodiment of the present invention.

[0020] In the following explanation, for convenience, the direction of maximum luminosity on the light-emitting surface 11 of the light-emitting element 10, and the direction of the center of the light distribution characteristic spread, will be defined as the optical axis A direction. The optical axis A direction is perpendicular to the light-emitting surface 11. In the optical axis A direction, the arrow +z direction is considered the upper side, and the arrow -z direction is considered the lower side. In the following explanation, among the directions perpendicular to the optical axis A direction, the left and right directions in Figures 1 to 5 will be defined as the x direction. In the x direction, the left side will be the -x direction, and the right side will be the +x direction. In the directions perpendicular to the optical axis A direction, the depth direction that penetrates the plane of the paper in Figure 1 will be defined as the y direction. In the y direction, the front side will be the -y direction, and the back side will be the +y direction. In the x and y directions, the direction toward the center will be considered the inward direction, and the direction toward the center will be considered the outward direction. However, the directions described above are used for convenience of explanation, and different directions may be defined depending on the usage situation in which the light-emitting device 1 is placed.

[0021] As shown in Figure 1, the light-emitting device 1 according to this embodiment comprises a light-emitting element 10, a lens 20, and a substrate 30.

[0022] The light-emitting element 10 is a semiconductor element that emits light from its light-emitting surface 11. The light-emitting element 10 is mounted on the upper surface 31 of the substrate 30 such that the optical axis A direction of the light-emitting surface 11 is facing upwards. The light-emitting element 10 is, for example, a light-emitting diode (LED). The light-emitting element 10 may be, for example, a single light-emitting diode, or it may be a chip-on-board (COB) with multiple LED chips mounted on it. The substrate 30 is configured with circuits that control the current supplied to the light-emitting element 10. The shape of the light-emitting surface 11 of the light-emitting element 10 is, for example, circular or approximately circular. When the light-emitting surface 11 of the light-emitting element 10 is circular, the maximum width W1 corresponds to the diameter of the light-emitting surface 11 of the light-emitting element 10. The maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 is preferably, for example, 10% or more of the maximum width (diameter) of the lens 20. The maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 may be, for example, 0.5 to 3.0 mm. More preferably, the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 may be, for example, 0.8 to 3.0 mm.

[0023] Figure 2 shows the relationship between the simulation results of the illuminance distribution and a predetermined region S when the distance from the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 is a first distance. Figure 3 shows the relationship between the simulation results of the illuminance distribution and a predetermined region S when the distance from the light-emitting surface 11 is a second distance.

[0024] Figures 2 and 3 show the simulation results of the illuminance distribution of light emitted from the light-emitting surface 11 at a first distance and a second distance from the light-emitting element 10, where the maximum width W1 of the light-emitting surface 11 is 1.4 mm. In Figures 2 and 3, the maximum width of region S is 1.6 mm. Also, in Figures 2 and 3, the first distance is 0.2 mm and the second distance is 0.6 mm.

[0025] At the first distance shown in Figure 2, 86% of the light emitted from the light-emitting surface 11 of the light-emitting element 10 is incident within a region S approximately equal to the area of ​​the light-emitting surface 11, while 86% of the light incident outside region S is incident outside of region S. It is 14%. At the second distance shown in Figure 3, 54% of the light emitted from the light-emitting surface 11 of the light-emitting element 10 is incident within a region S that is approximately equal to the area of ​​the light-emitting surface 11, and 46% of the light is incident outside of region S.

[0026] According to Figures 2 and 3, in the light-emitting device 1, as the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 increases, the amount of light incident outside the predetermined region S increases compared to the amount of light incident within the region S. In other words, according to Figures 2 and 3, when region S is applied to the first region 211 of the lens 20, as the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 increases, the amount of light incident in the region outside the first region 211 of the incident surface 21 of the lens 20 increases.

[0027] The lens 20 has an incident surface 21 into which light emitted from the light-emitting element 10 enters, and an exit surface 22 into which light that enters from the incident surface 21 exits. The lens 20 may be made of a light-transmitting resin such as polycarbonate, polyester, acrylic resin, or cyclic olefin polymer, or it may be made of glass.

[0028] Figure 4 is a side view showing the positional relationship between the light-emitting element 10 and the lens 20 when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is at its minimum. Figure 5 is a side view showing the positional relationship between the light-emitting element 10 and the lens 20 when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is at its maximum.

[0029] As shown in Figures 4 and 5, the lens 20 is configured to move a predetermined distance D in the optical axis A direction relative to the light-emitting element 10 by a mechanism (not shown). The distance D is the difference between the maximum distance D2 and the minimum distance D1 between the light-emitting surface 11 and the incident surface 21 of the lens 20. Specifically, the distance between the light-emitting surface 11 and the incident surface 21 of the lens 20 is the shortest distance between the light-emitting surface 11 and the first region 211 of the lens 20. The mechanism for moving the lens 20 can be any mechanism that allows the lens 20 to move in the optical axis A direction by a cylindrical holding part that holds the outer circumference of the lens 20. The distance D is, for example, 0.1 to 1.0 mm. More preferably, the distance D is, for example, 0.4 to 1.0 mm.

[0030] The incident surface 21 of the lens 20 has a first region 211 and a second region 212. Furthermore, at least a reflective prism 213 is provided in the second region 212.

[0031] The first region 211 of the incident surface 21 is the center of the luminosity of the light-emitting surface 11 of the light-emitting element 10, and is the surface facing the center position of the light-emitting surface 11. The first region 211 is formed as a flat surface or a substantially flat surface. The first region 211 of the incident surface 21 may be a flat surface without lens cuts, or it may be a flat surface with lens cuts such as a prism, microlens, or textured surface. If lens cuts are provided in the first region 211, it is preferable to provide a refractive prism with an inclination angle of 20° or less. As shown in Figures 4 and 5, the first region 211 of the incident surface 21 is incident on the light L1 and L21 emitted from the light-emitting surface 11 of the light-emitting element 10, which is mainly emitted in a direction centered on the optical axis A and travels substantially perpendicular to the incident surface 21 of the lens 20. That is, the first region 211 of the incident surface 21 is incident on the light L1 and L21 near the center of the luminosity. In the first region 211 of the incident surface 21, regardless of whether the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the maximum distance D2 or the minimum distance D1 within the range of travel distance D, light L1 or L21 near the center of the luminous intensity is incident. The first region 211 of the incident surface 21 is the region on the incident surface 21 that corresponds to region S shown in Figures 2 and 3.

[0032] The second region 212 of the incident surface 21 is located on the incident surface 21, around the first region 211, that is, outside the x and y directions which are perpendicular to the optical axis A. 12 is a flat surface with lens cuts, and specifically, multiple reflective prisms (TIR lenses; Total Internal Reflection lenses) 213 are formed thereon. As shown in Figure 5, the second region 212 of the incident surface 21 is incident on the second region 212 of the incident surface 21, and mainly the light L22 that travels at an angle to the incident surface 21 of the lens 20, which is emitted from the light-emitting surface 11 of the light-emitting element 10.

[0033] In the second region 212, light L22 incident on one reflective prism 213 is reflected by the Fresnel surface of an adjacent reflective prism 213, causing its direction of propagation to change to the direction of the optical axis A. In other words, the reflective prism 213 focuses the light L22, which is traveling at an angle with respect to the incident surface 21 of the lens 20, in the direction of the optical axis A. The angle θ of the inclined surface of the reflective prism 213 is preferably a large inclination angle of, for example, 30° or more. The second region 212 of the incident surface 21 corresponds to the region outside of region S shown in Figures 2 and 3 on the incident surface 21.

[0034] Based on the relationship between the illuminance distribution and a predetermined region S when the distance from the light-emitting surface 11 of the light-emitting element 10 is a predetermined distance, as shown in Figures 2 and 3, the ratio of the maximum width W2 of the first region 211 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 (W2 / W1) is set to a predetermined ratio including the same value. In this way, the light-emitting element 1 can obtain a change in the light distribution of the light emitted from the light-emitting element 1 due to the difference in distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20, as described below.

[0035] Figure 6 shows the simulation results of the illuminance distribution when the distance between the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 and the incident surface 21 of the lens 20 is minimized. Figure 7 shows the simulation results of the illuminance distribution in the x-direction when the distance between the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 and the incident surface 21 of the lens 20 is minimized. Figure 8 shows the simulation results of the illuminance distribution in the y-direction when the distance between the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 and the incident surface 21 of the lens 20 is minimized.

[0036] Figure 9 shows the simulation results of the illuminance distribution when the distance between the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 and the incident surface 21 of the lens 20 is at its maximum. Figure 10 shows the simulation results of the illuminance distribution in the x-direction when the distance between the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 and the incident surface 21 of the lens 20 is at its maximum. Figure 11 shows the simulation results of the illuminance distribution in the y-direction when the distance between the light-emitting surface 11 of the light-emitting element 10 of the light-emitting device 1 and the incident surface 21 of the lens 20 is at its maximum.

[0037] As shown in Figures 2 and 3, based on the fact that the light distribution of light incident on the incident surface 21 of the lens 20 differs depending on the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20, the light-emitting device 1 can significantly change the light distribution of light emitted from the light-emitting device 1 even when the lens travel distance D is short, as shown in Figures 6 to 11, by using the first region 211 and the second region 212 on the incident surface 21 of the lens 20.

[0038] Specifically, in the light-emitting device 1, as shown in Figure 4, when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is short, most of the light incident on the lens 20 passes through the first region 211 on the incident surface 21. The first region 211, which is formed on a flat or substantially flat surface, allows the incident light to pass through, thereby making the light emitted from the lens have a wide light distribution that is close to the light distribution characteristics of the light-emitting element 10.

[0039] On the other hand, in the light-emitting device 1, as shown in Figure 5, when the distance between the light-emitting surface 11 and the incident surface 21 of the lens 20 is greater than the state shown in Figure 4, the light incident on the lens 20 includes not only the light L21 that passes through the first region 211 on the incident surface 21, but also the light L22 that is incident on the second region 212. When the distance between the light-emitting surface 11 of the light-emitting device 10 and the incident surface 21 of the lens 20 is increased, the light L22 that is incident on the increased second region 212 of the incident surface 21 is reflected by the reflective prism 21 By focusing the light in the direction of optical axis A as described in 3, the light-gathering ability can be improved.

[0040] Figure 12 is a graph showing the relationship between the ratio W2 / W1 of the maximum width W2 of the first region 211 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10, and uniformity U or illuminance I in the light-emitting device 1. In Figure 12, the uniformity U, indicated by a white circle, represents the uniformity of the light emitted from the lens 20 when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the maximum distance D2. In Figure 12, the illuminance I, indicated by a black circle, represents the illuminance of the light emitted from the lens 20 when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the minimum distance D1.

[0041] As shown in Figure 12, in the light-emitting device 1, the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10, in which both uniformity U and illuminance I can be achieved at high values, is within a predetermined range centered on 1.

[0042] Based on the relationship between the illuminance distribution at a distance from the light-emitting surface 11 of the light-emitting element 10 and a predetermined region S shown in Figures 2 and 3, and the relationship with uniformity U or illuminance I shown in Figure 12, the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 is set to a predetermined ratio including equivalent values. Specifically, the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 is 0.2 to 1.5. In this way, the light-emitting device 1 can obtain a change in light distribution due to the difference in distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20, as described below.

[0043] Figure 13 is a graph showing the relationship between the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10, and the gain G of the central illuminance in the light-emitting device 1.

[0044] In the light-emitting device 1, the central illuminance gain is the ratio of the central illuminance of the light emitted from the lens 20 when the distance between the light-emitting surface 11 and the incident surface 21 of the lens 20 is the minimum distance D1, to the central illuminance of the light emitted from the lens 20 when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the maximum distance D2. As shown in Figure 13, when the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 is in the range of 0.2 to 1.5 as described above, the central illuminance gain G is approximately in the range of 2.0 to 5.0.

[0045] The light-emitting device 1 configured as described above has a lens 20 that can move a predetermined distance D in the direction of the optical axis A, which is the direction of the center of the luminous intensity of the light-emitting surface 11 of the light-emitting element 10, and the incident surface 21 of the lens 20 has a first region 211 which is formed on a substantially flat surface facing the center of the luminous intensity of the light-emitting surface 11 of the light-emitting element 10, and a second region 212 which is provided around the first region 211 and in which a plurality of reflective prisms 213 are formed, and the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 is a predetermined ratio including the same.

[0046] Specifically, for example, the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 may be 0.2 to 1.5.

[0047] The distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20, which changes as the lens 20 moves, may specifically be 0.1 to 1.0 mm.

[0048] As described above, in the light-emitting device 1, the light-emitting surface 11 of the light-emitting element 10 and the lens 20 The difference in distance from the incident surface 21 changes the light distribution of the light incident on the first region 211 of the incident surface 21 and the light incident on the second region 212 of the incident surface 21, thereby changing the light distribution of the light emitted from the light-emitting device 1. Furthermore, both high uniformity and high illuminance can be achieved simultaneously in the light emitted from the light-emitting device 1.

[0049] The first region of the light-emitting surface 11 may be provided with at least one of a prism, a microlens, or a textured surface.

[0050] By doing so, the uniformity and / or illuminance of the light emitted from the light-emitting device 1 can be adjusted. In addition, the appearance of the light-emitting device 1 when viewed from the emission surface 22 side of the lens 20 can be improved. Specifically, by reducing the transmission of light from the outside, the visibility of the light-emitting element 10 visible through the lens 20 can be reduced, thereby improving the appearance.

[0051] The ratio of the central illuminance of light emitted from the lens 20 when the distance D between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the minimum distance D1, to the central illuminance of light emitted from the lens 20 when the distance D between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the maximum distance D2, may be between 2.0 and 5.0.

[0052] By doing so, it is possible to obtain a change in the central illuminance of the light emitted from the light-emitting device 1 according to the distance D. Furthermore, for example, if the light-emitting device 1 is mounted on a camera, by changing the distance D, it is possible to set the illuminance during telephoto shooting to a higher value compared to the illuminance during close-up shooting.

[0053] Therefore, with the light-emitting device 1, it is possible to change the irradiation range even if the amount of change in the distance between the lens 20 and the light-emitting element 10 in the direction of light irradiation is small.

[0054] Figure 14 is a schematic side view showing the configuration of a modified light-emitting device 1B according to the present invention.

[0055] As shown in Figure 14, the light-emitting device 1B differs from the light-emitting device 1 described earlier in that a support portion 23 is provided on the incident surface 21 of the lens 20B, which protrudes downward in the optical axis A direction toward the upper surface 31 of the substrate 30 on which the light-emitting element 10 is mounted. By providing the support portion 23 on the lens 20B, the light-emitting device 1B can set a minimum distance D1 between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20. Furthermore, when the distance between the light-emitting surface 11 of the light-emitting element 10 and the incident surface 21 of the lens 20 is the minimum distance D1, both ends (outermost periphery) of the lens 20 can be supported relative to the substrate 30, thus keeping the inclination of the lens 20 constant. For this reason, the light-emitting device 1B can provide more stable optical performance.

[0056] Furthermore, those skilled in the art may modify the present invention as appropriate in accordance with prior art knowledge. Such modifications, insofar as they still possess the configuration of the present invention, are of course included within the scope of the present invention.

[0057] For example, in the light-emitting device 1, the dimensions of the maximum width W1 of the light-emitting element 10 and the light-emitting surface 11, and the dimensions of the maximum width W2 of the first region 211 on the lens 20 and the incident surface 21 are not limited to the examples described above. In other words, in the light-emitting device 1, the ratio W2 / W1 of the maximum width W2 of the first region 211 of the lens 20 to the maximum width W1 of the light-emitting surface 11 of the light-emitting element 10 is within the range described above, and the travel distance D of the lens 20 according to each dimension can be set to achieve the effects described above.

[0058] For example, in the light-emitting devices 1 and 1B, an example in which lenses 20 and 20B move was described, but the present invention is not limited to this. A light-emitting device is also acceptable. [Explanation of Symbols]

[0059] 1,1B…Light-emitting device, 10…Light-emitting element, 11…Light-emitting surface, 20,20B…Lens, 21…Incident surface, 22…Output surface, 23…Support part, 30…Substrate, 31…Top surface, 211…First region, 212…Second region, 213…Reflective prism, A…Optical axis, D…Travel distance, D1…Minimum distance (distance), D2…Maximum distance (distance), G…Gain, I…Illuminance, L1,L21,L22…Light, S…Region, U…Uniformity, W1…Maximum width of light-emitting surface, W2…Maximum width of first region, θ…Angle

Claims

1. A light-emitting element that emits light from its light-emitting surface, A lens having an incident surface into which the light emitted from the light-emitting element enters and an outgoing surface from which the light exits, Equipped with, The aforementioned lens is, The light-emitting element is movable a predetermined distance in the direction of the center of the luminous intensity of the light-emitting surface. The incident surface is, It has a first region formed on a substantially flat surface opposite to the center of the luminous intensity, and a second region provided around the first region where a plurality of reflective prisms are formed. The ratio of the maximum width of the first region to the maximum width of the light-emitting surface is a predetermined ratio that includes the same value. Light-emitting device.

2. The ratio of the maximum width of the first region to the maximum width of the light-emitting surface is 0.2 to 1.

5. The light-emitting device according to claim 1.

3. The distance between the light-emitting surface and the incident surface is 0.1 to 1.0 mm. The light-emitting device according to claim 1 or 2.

4. The first region is provided with at least one of a prism, a microlens, or a textured surface. The light-emitting device according to claim 1.

5. The aforementioned reflective prism has an inclined surface angle of 30° or more. The light-emitting device according to claim 1.

6. The ratio of the central illuminance of the light emitted from the lens when the distance between the light-emitting surface and the incident surface is minimum, to the central illuminance of the light emitted from the lens when the distance between the light-emitting surface and the incident surface is maximum, is between 2.0 and 5.

0. The light-emitting device according to claim 1.

7. The light-emitting element is provided on the upper surface of the substrate, The incident surface is provided with a support portion that protrudes toward the upper surface. The light-emitting device according to claim 1.

Images