JP4330716B2 - Floodlight device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light projecting device, and more particularly to an in-vehicle optical beacon information light projecting device used for VICS (road traffic information communication system).
[0002]
[Prior art]
A conventional in-vehicle optical beacon information projector / receiver is described in Japanese Patent Application Laid-Open No. 10-38991. This light projecting / receiving device is formed by providing a plurality of LEDs (light emitting diodes) and PD (photodiodes) on the same circuit board. As a light projecting device used in such an in-vehicle optical beacon information projecting / receiving device, the one described in Japanese Patent Application Laid-Open No. 8-272319 has been devised.
[0003]
[Problems to be solved by the invention]
Although the above projector is excellent as a light source for VICS, it has been desired to improve the light emission efficiency. The present invention has been made in view of such a problem, and an object thereof is to provide a light projecting device capable of improving the light emission efficiency.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, a light projecting device according to the present invention includes a package body having a light emitting opening, a plurality of light emitting elements disposed in the light emitting opening, and a package so as to close the light emitting opening. In a light projecting device comprising a light emitting element lens attached to a main body, the plurality of light emitting elements are arranged along the longitudinal direction of the package main body, and the center of curvature of the outer surface of the light emitting element lens is parallel to the longitudinal direction. A cylindrical lens is formed as a line segment, and the inner surface of the light emitting element lens forms a cylindrical lens group, and the center of curvature of each lens in the cylindrical lens group is on an extension line of each light emitting direction of the plurality of light emitting elements. becomes the line segment which is perpendicular to both the longitudinal direction and the light emitting direction while the position, the radius of curvature of the cylindrical lens, the Shirindorikarure It is larger than the radius of curvature of each lens in's group.
Further, the light projecting device according to the present invention is attached to the package body so as to close the package body having the light emitting opening, the plurality of light emitting elements disposed in the light emitting opening, and the light emitting opening. A light emitting device including a lens for a light emitting element, wherein the plurality of light emitting elements are arranged along a longitudinal direction of the package body, and the outer surface of the lens for the light emitting element is a cylindrical lens whose center of curvature is a line segment parallel to the longitudinal direction. The inner surface of the light emitting element lens constitutes a convex lens group, and the center of curvature of each lens in the convex lens group is located on the extension line of each light emitting direction of the plurality of light emitting elements, and the radius of curvature of the cylindrical lens Is larger than the radius of curvature of each lens in the convex lens group.
Further, the package body is resin-molded so as to have a light emitting opening on one side of the lead frame, and the light emitting element is a light emitting diode and is mounted on the lead frame. To do .
[0006]
In these light projecting devices, the light from the light emitting element is efficiently condensed by the inner surface and the outer surface of the light emitting element lens.
[0007]
The radius of curvature of the cylindrical lens is preferably larger than the radius of curvature of each lens in the cylindrical lens group. Moreover, it is preferable that the curvature radius of a cylindrical lens is larger than the curvature radius of each lens in a convex lens group. Since the outer surface is farther from the light emitting element than the inner surface, the desired directivity can be obtained even if the curvature radius of the cylindrical lens is increased. Thereby, the thickness of the lens for light emitting elements can be reduced.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a light projection device according to an embodiment of the invention will be described. The same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.
[0009]
1 is a plan view of the main part of the light projecting device, FIG. 2 is a front view of the main part of the light projecting device, and FIG. 3 is a right side view of the main part of the light projecting device.
[0010]
The light projecting device according to the present embodiment includes a package body H formed by resin molding so as to have a light emitting opening 1op on one surface side (upper surface side) of a lead frame that is a rigid plate-like conductor, A plurality of infrared light emitting elements LED1, LED2, LED3, LED4, LED5, and LED6 (light emitting diodes) mounted on the lead frame in one opening 1op, and mounted on the package body H so as to close the first opening 1op And a light emitting element lens L.
[0011]
The package body H is formed by resin molding so as to have an opening 1op. As a resin material constituting the package body H, PPS, a liquid crystal polymer, an epoxy resin, or the like which is a heat resistant resin is used.
[0012]
Each of the light emitting elements LED1 to LED6 is die-bonded to a die pad portion (1D to 6D) of the lead frame. The light emitting element lens L is attached to the package main body H so as to close the opening 1op, and each die pad portion is connected to the outer lead portions 1F to 6F and 1B to 6B exposed to the outside of the package main body H.
[0013]
The light emitting elements LED1, LED2, and LED3 are connected in series, the light emitting elements LED4, LED5, and LED6 are connected in series, and each light emitting element group is connected in parallel with the die pad portions 3D and 4D as common electrodes.
[0014]
The area of the lead frame between the outer lead portion and the die pad portion is an inner lead portion. In addition, in the initial stage of manufacture, the lead frame is configured to include a frame made of a plate-like conductor that connects the end portions of the outer lead portion, but this is removed after each element is attached.
[0015]
A resin material that is transparent to infrared rays is coated on the bottom surface in the opening 1op. For example, this is made of a heat-resistant, flexible, or chemical-resistant resin such as a silicone resin. The light emitted from the light emitting element LED is condensed through the lens L so as to have a predetermined directivity and becomes substantially parallel light. However, it is preferable that the difference in refractive index between the lens L and the opening 1op is relatively large. Therefore, in the opening 1op, the resin material RSN2 is provided so that air having a small refractive index is interposed between the resin material and the lens L. This may be a coating and does not need to be filled.
[0016]
The die pad portion provided with the light emitting element will be described in detail. Since the functional structures of the die pad portions of the light emitting elements LED1, LED2, LED3, LED4, LED5, and LED6 are the same, only the light emitting element LED1 will be described here.
[0017]
FIG. 19 is a longitudinal sectional view of the vicinity of the light emitting diode LED1. The light emitting diode LED1 is attached to the center in the recess provided in the die pad portion 1D. The concave portion has a circular bottom surface RF1 having a surface parallel to the flat portion FLT constituting the peripheral region of the concave portion, and an inner side surface RF2 constituted by a conical surface connecting the outer periphery of the bottom surface RF1 and the flat portion FLT. It constitutes a mortar shape. The inner side surface RF2 may be curved outward even in a cross section perpendicular to the bottom surface RF1, and in this case, the recess constitutes a cup shape. For example, the cup shape is set to an outer diameter of 1.3 mm, an inner diameter of 0.61 mm, and a depth of 0.3 mm, and the distance between the recesses is set to 2.9 mm.
These bottom face RF1 and inner side face RF2 constitute a reflecting mirror, and reflect light from the light emitting element leaking to the side face in the surface direction. In other words, the lead frame is made of a material containing copper, but the surface is plated with a metal such as Au, Pd, Al, or Ag which is a highly reflective material.
[0018]
Next, the lens L will be described.
[0019]
4 is a plan view of the lens L, FIG. 5 is a front view of the lens L, and FIG. 6 is a right side view of the lens L. The lens L has an outer surface Lo located outside the package body H and an inner surface Li located inside. The outer surface Lo constitutes a semi-cylindrical lens (cylindrical lens) constituting a line segment whose center of curvature coincides with the longitudinal direction (width direction) of the package body H. The longitudinal direction of the package body H coincides with the arrangement direction of the light emitting elements LED1 to LED6. The inner surface Li corresponds to a direction (front-rear direction) perpendicular to both the longitudinal direction and the depth direction of the opening 1op (light emitting direction of the light emitting element), and a plurality of line segments arranged in the longitudinal direction are respectively A cylindrical lens group including a plurality of cylindrical lenses Li <b> 1 to Li <b> 6 having a center of curvature is configured.
[0020]
Light emitted from each of the light emitting elements LED1 to LED6 is condensed in the width direction and the front-rear direction by the cylindrical lenses Li and Lo, respectively. The directivity in the width direction of the light emitted from the light projecting unit 1 is set to ± 20 °, and the directivity in the front-rear direction is set to ± 10 °. When the unit 1 is mounted on a vehicle, the light emission direction is inclined by an angle α (45 °) with respect to the horizontal plane. Therefore, the directivity in the front-rear direction is determined by using the angle α from the horizontal plane as a reference ray. Is set as the elevation angle.
[0021]
The maximum separation distance between the surface of the outer cylindrical lens Lo and the flat portion FLT of the lead frame is set to 4.5 mm, for example, and the radius of curvature of the cylindrical lens Lo is set to 3.1 mm. The shortest distance between the surface of the inner surface side cylindrical lens Li and the flat portion FLT of the lead frame is set to 1.3 mm, for example, and the radius of curvature of the cylindrical lens Li is set to 3 mm.
[0022]
The cylindrical lens group may be a convex lens group such as an aspherical surface or a spherical lens, as will be described later.
[0023]
Engagement portions LFL and LFR projecting along the thickness direction are integrally formed at both ends of the lens L. These contact with the side surfaces at both ends in the longitudinal direction of the package body H, and the longitudinal direction of the lens L with respect to the package body H Restricts directional positioning and longitudinal relative movement. The engaging portions LFL, LFR are provided with through holes LTH extending along the longitudinal direction, and the projecting portions HFL, HFR (see FIG. 2) projecting in the longitudinal direction from the side surface of the package body H pass through the through holes LTH. The lens is fitted into the hole LTH, and the positioning of the lens L with respect to the package body H in the front-rear direction and the relative movement in the front-rear direction are restricted. The engaging portions LFL and LFR may have a slit extending along the depth direction, or a recess extending from the inside toward the outside, instead of the through hole LTH.
[0024]
As described above, the light projecting device includes the package body H having the light emitting opening 1op, the plurality of light emitting elements LED1 to LED6 arranged in the light emitting opening 1op, and the light emitting opening 1op. In the light projecting device including the light emitting element lens L attached to the package body H so as to be closed, the plurality of light emitting elements LED1 to LED6 are arranged along the longitudinal direction of the package body, and the outer surface of the light emitting element lens L Lo constitutes a cylindrical lens in which the center of curvature is a line segment parallel to the longitudinal direction, and the inner surface Li of the light emitting element lens L constitutes the cylindrical lens groups Li1 to Li6, and each of the cylindrical lens groups Li1 to Li6. The center of curvature of the lens is located on the extension line of the light emitting direction of each of the plurality of light emitting elements LED1 to LED6. A line segment which is perpendicular to both the longitudinal direction and the light emitting direction.
[0025]
In this light projecting device 1U, the light from the light emitting element LED is efficiently condensed by the inner surface Li and the outer surface Lo of the light emitting element lens L, and this can easily function as a light projecting device for VICS. Can do.
[0026]
The curvature radius of the cylindrical lens Lo is larger than the curvature radius of each lens in the cylindrical lens groups Li1 to Li6. Since the outer surface Lo is farther from the light emitting element than the inner surface Li, the desired directivity can be obtained even if the radius of curvature of the cylindrical lens is increased. Thereby, the thickness of the lens for light emitting elements can be reduced.
[0027]
The light projecting device 1U may be integrated with the light receiving device.
[0028]
7 is a plan view of the main part of such a light projecting / receiving apparatus, FIG. 8 is a front view of the main part of the light projecting / receiving apparatus, and FIG. 9 is a right side view of the main part of the light projecting / receiving apparatus.
[0029]
The present light projecting / receiving device is different from the above in that the light projecting / receiving device includes a light receiving element (Si photodiode) PD arranged adjacent to the above-described present light projecting device 1U. The light receiving element PD is fixed on a die pad portion D11 disposed in an opening 2op formed adjacent to the opening 1op of the package body, and the output is an outer lead portion 10B that applies a reverse bias to the light receiving element PD. , 11B. The opening 2op is filled with a transparent resin material such as silicone resin. In addition, the shape of the light emitting element side engaging part of a lens part is changed with this deformation | transformation. A partition IW is provided between the openings 1op and 2op.
[0030]
10 is a plan view of the lens L of the present embodiment, FIG. 11 is a front view of the lens L, and FIG. 12 is a right side view of the lens L.
[0031]
At the end of the lens L on the light receiving element PD side, an engaging portion LFR protruding along the longitudinal direction is integrally formed instead of the right engaging portion LFR of the above-described embodiment. It fits into a U-shaped engaging portion HFR provided on the partition wall IW (see FIG. 8), and the lens L is positioned relative to the package body H in the longitudinal direction and moved in the longitudinal direction (moving on the light receiving element PD side). ).
[0032]
The lens shape can be changed.
[0033]
FIG. 13 is a plan view of such a main part of the projector, FIG. 14 is a front view of the main part of the projector, FIG. 15 is a right side view of the main part of the projector, and FIG. 17 is a front view of the lens L, and FIG. 18 is a right side view of the lens L. The light projecting device according to the present embodiment is the same as that shown in FIGS. 1 to 6 except for the shape of the inner surface Li of the lens L.
[0034]
In this apparatus, the inner surface Li of the light emitting element lens L constitutes the convex lens groups Li1 to Li6, and the center of curvature of each lens in the convex lens groups Li1 to Li6 is the light emission of each of the plurality of light emitting elements LED1 to LED6. Located on the direction extension line. Also in the light projecting device, the light from the light emitting element LED is efficiently condensed by the inner surface Li and the outer surface Lo of the light emitting element lens L, and this can easily function as a light projecting device for VICS. .
[0035]
The convex lenses Li1 to Li6 are spherical lenses, but may be aspherical lenses. Further, the radius of curvature of the cylindrical lens Lo is larger than the radius of curvature of each lens in the convex lens groups Li1 to Li6, and the thickness of the light emitting element lens L can be reduced in the same manner as described above.
[0036]
As a modification of the light projecting and receiving device shown in FIG. 7, a lens may be arranged also on the light receiving element PD.
[0037]
20 is a perspective view of the main part of such a light projecting / receiving apparatus, FIG. 21 is a plan view of the main part of the light projecting apparatus, FIG. 22 is a front view of the main part of the light projecting apparatus, and FIG. FIG.
[0038]
A light receiving element lens L ′ is integrally formed on the light emitting element lens L, and the light receiving element lens L ′ closes the opening 2op. On the right end side of the lens L ′, engaging portions LFR ′ and HFR ′ and a through hole LTH ′ having the same structure as that of the right end side of the lens L shown in FIG. 2 are provided to fix and position the lens. Yes.
[0039]
The outer surface Lo ′ of the lens L ′ constitutes a cylindrical lens in which the center of curvature is a line segment parallel to the longitudinal direction (light emitting element arrangement direction). The inner surface Lo ′ of the lens L ′ is parallel to the light receiving surface of the light receiving element PD and is flat.
[0040]
The radius of curvature of the light receiving element side cylindrical lens Lo ′ is larger than the radius of curvature of the light emitting element side cylindrical lens Lo. The area of the light receiving surface of the light receiving element PD is smaller than the cross-sectional area perpendicular to the depth direction of the light receiving element opening 2op. Incident light to the light receiving element PD is condensed by the lens L ′ in a direction (front-rear direction) perpendicular to both the longitudinal direction and the depth direction, so that the amount of light incident into the light receiving element PD is increased. Can do. As the lens L ′ is installed, the thickness of the transparent resin material filled in the opening 2op is reduced.
[0041]
The light-emitting element lens L and the light-receiving element lens L ′ are integrally formed, but their boundary portion is located on the partition wall IW, and the inner surface of the lens at the boundary portion is erected in the thickness direction. A concave groove is formed so as to be fitted to the upper end portion.
[0042]
The light emitted from the light emitting element LED is inhibited from traveling in the lateral direction by reflection by the concave reflecting mirror RF2 and shielding by the partition wall IW shown in FIG. That is, the emitted light from the light emitting element LED is difficult to enter the light receiving element PD disposed on the lateral extension line. In this example, since the boundary portion is provided between the integrally formed lenses L and L ′, the light transmission efficiency in the lateral direction through the lens is reduced, and the optical link between the light emitting element LED and the light receiving element PD is further increased. Can be suppressed.
[0043]
【The invention's effect】
As described above, in this apparatus, light from the light emitting element is efficiently collected.
[Brief description of the drawings]
FIG. 1 is a plan view of a main part of a light projecting device.
FIG. 2 is a front view of a main part of a light projecting device.
FIG. 3 is a right side view of a main part of the light projecting device.
4 is a plan view of a lens L. FIG.
5 is a front view of a lens L. FIG.
6 is a right side view of a lens L. FIG.
FIG. 7 is a plan view of a main part of the light projecting / receiving device.
FIG. 8 is a front view of a main part of the light projecting / receiving device.
FIG. 9 is a right side view of a main part of the light projecting / receiving device.
10 is a plan view of another lens L. FIG.
11 is a front view of another lens L. FIG.
12 is a right side view of another lens L. FIG.
FIG. 13 is a plan view of a main part of a light projecting device according to another embodiment.
FIG. 14 is a front view of a main part of a light projecting device according to another embodiment.
FIG. 15 is a right side view of a main part of a light projecting device according to another embodiment.
16 is a plan view of a lens L in the apparatus of FIG.
17 is a front view of a lens L in the apparatus of FIG.
18 is a right side view of the lens L in the apparatus of FIG.
FIG. 19 is a longitudinal sectional view of the vicinity of the light emitting diode LED1.
FIG. 20 is a perspective view of a main part of the light projecting / receiving device.
FIG. 21 is a plan view of a main part of the light projecting device.
FIG. 22 is a front view of a main part of the light projecting device.
FIG. 23 is a right side view of the main part of the light projecting device.
[Explanation of symbols]
LED ... light emitting element, PD ... light receiving element, L ... lens, Li ... inner surface, Lo ... outer surface, H ... package body.

Claims (3)

A projection main body having a light emitting opening, a plurality of light emitting elements disposed in the light emitting opening, and a light emitting element lens attached to the package main body so as to close the light emitting opening. In the optical device,
The plurality of light emitting elements are arranged along a longitudinal direction of the package body,
The outer surface of the lens for light emitting element constitutes a cylindrical lens whose center of curvature is a line segment parallel to the longitudinal direction,
The inner surface of the light emitting element lens constitutes a cylindrical lens group,
The center of curvature of each lens in the cylindrical lens group is located on the extension line of each light emission direction of the plurality of light emitting elements and is a line segment orthogonal to both the longitudinal direction and the light emission direction ,
The light projection device according to claim 1, wherein a curvature radius of the cylindrical lens is larger than a curvature radius of each lens in the cylindrical lens group . A projection main body having a light emitting opening, a plurality of light emitting elements disposed in the light emitting opening, and a light emitting element lens attached to the package main body so as to close the light emitting opening. In the optical device,
The plurality of light emitting elements are arranged along a longitudinal direction of the package body,
The outer surface of the lens for light emitting element constitutes a cylindrical lens whose center of curvature is a line segment parallel to the longitudinal direction,
The inner surface of the lens for the light emitting element constitutes a convex lens group, and the center of curvature of each lens in the convex lens group is located on each light emission direction extension line of the plurality of light emitting elements ,
The light projection device according to claim 1, wherein a curvature radius of the cylindrical lens is larger than a curvature radius of each lens in the convex lens group . The package body is resin-molded so as to have the light emitting opening on one side of a lead frame, and the light emitting element is a light emitting diode, and is mounted on the lead frame. The light projecting device according to claim 1 or 2.

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