JP3118799B2 - Outer lens for semiconductor light emitting module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens, and more particularly, to a small, thin and high-power outer lens for a semiconductor light emitting module.

[0002]

2. Description of the Related Art A so-called semiconductor light emitting module which constitutes a semiconductor light emitting device in which a plurality of semiconductor light emitting devices or semiconductor light emitting elements are incorporated in a single envelope is known. FIG.
The conventional semiconductor light emitting module shown in FIG. 1 includes a printed circuit board (1), a plurality of light emitting diodes (2) mounted on the printed circuit board (1), and a printed circuit board (1) surrounding the light emitting diode (2). A plurality of light emitting diodes (2) are formed integrally with their respective light distribution directions aligned. Light emitting diode (2)
Has an external lead (4) and a lens (5) fixed to an end of the external lead (4). Although not shown, the external lead (4) includes a header (dish-shaped support electrode body), and the lens (5) seals the light emitting diode element fixed to the header of the external lead (4). Also, in order to smooth road traffic and improve safety, VICS (Vehicle Information Communic) that transmits and receives traffic information to and from vehicles in real time by adding a communication function to a car navigation system.
ation System) has been proposed and has been in operation in some areas since April 1996. As shown in FIG.
In CS, bi-directional optical communication is performed between an on-board unit including a car navigation system installed on a running vehicle and a ground unit installed on the side of the road, and the light source of an optical beacon, which is a communication medium of VICS, A collective lamp type infrared light emitting diode module is used as a semiconductor light emitting module.

[0003]

By the way, in a semiconductor light emitting module mounted on an automobile for the purpose of optical communication, it is particularly required that the module has a small area (small size) and a small thickness. Here, the semiconductor light emitting module of FIG. 20 has a configuration in which an external lead (4) is provided and a separately completed resin-sealed light emitting diode (2) is arranged on a circuit board (1). Since the width L and the height H of 5) are relatively large, such requirements cannot be satisfied. Accordingly, it is an object of the present invention to provide an outer lens for a semiconductor light emitting module which is optimal as a lens of a light source for optical communication and the like, and which can be reduced in size, thickness and output.

[0004]

The outer lens (15) for a semiconductor light emitting module of the present invention, which suppresses the scattering of light emitted from a plurality of semiconductor light emitting devices (12), is formed in a plate shape from a translucent material. A lens body (15c), a plurality of lens portions (33) formed integrally with the lens body (15c) and having an outer surface protruding from one main surface (15a) of the lens body (15c); 15c) on the other major surface (15
b) and a leg (15d) attached to a circuit board (11) to which a plurality of semiconductor light emitting devices (12) are fixed. The legs (15d) are provided on both sides of the lens body (15c), and one leg (15d) of the lens body (15c) has a curved shape. The outer lens (15) according to the present invention includes a leg (15) projecting from the other main surface (15b) of the lens body (15c).
Since d) can be mounted on the circuit board (11), no enclosure is required, mounting is easy, and the semiconductor light emitting module can be reduced in size and thickness. Particularly, since the leg (15d) on one side of the lens body (15c) is formed in a curved shape, the leg (1
The outer lens (15) can be easily attached to the circuit board (11) without applying excessive stress to 5d).

In the embodiment of the present invention, the lens portion (33)
Has an aspherical, approximately half-egg surface and a radius ratio along the short axis (33a) and the long axis (33b) of 2: 2.1 to 2: 5.
Range. By forming the lens portion (33) in this manner, it is possible to obtain a horizontally long directional characteristic required for a rectangular communication area of the ground machine without significantly impairing the front light output. Even if a true spherical lens is produced, optical distortion occurs due to partial shrinkage of the resin. However, by using a half-egg surface, problems due to shrinkage of the resin can be avoided. Further, a reflection wall (13) may be formed on the other main surface (15b) of the lens body (15c) to increase the luminous efficiency.
The claw (15e) formed at the tip of the leg (15d) is inserted into the opening (61) formed in the circuit board (11) and is locked on the peripheral wall (62) of the opening (61). You. By inserting the claw (15e) into the opening (61) formed in the circuit board (11), the outer lens (15) can be attached to the circuit board (11) with one touch by using a snap action. Furthermore, the lens body (15c) can be held in the correct position by attaching the protrusion (15f) formed between the legs (15d) to the hole (63) of the circuit board (11). It is.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an outer lens for a semiconductor light emitting module according to the present invention applied to a light emitting diode module will be described below with reference to FIGS.
The light emitting diode module shown in FIG.
1), chip-type light-emitting diodes (surface-mount light-emitting diodes) as semiconductor light-emitting devices (12) and reflective walls (13)
Are composed of an outer lens (15) integrally formed. The circuit board (11) is made of, for example, epoxy resin.
As shown in FIG. 2, one main surface (11
In a), a plurality of strip-shaped connection wiring conductors (16) and electrode terminals (17) are formed, and both are electrically connected by a connection wiring conductor (17a). As shown in FIG. 3, the connection wiring conductor (1) is also provided on the other main surface (11b) of the circuit board (11).
8) is formed. The connection wiring conductor (16) formed on one main surface (11a) extends in a first direction from one side surface (11c) of the circuit board (11) toward the other side surface (11d). A plurality of intermittent regions (19) are provided in the middle of the stretching direction.

As shown in FIG. 5, the chip type light emitting diode (12) comprises a light emitting element substrate (22) and a light emitting diode element (23) as a semiconductor light emitting element fixed to one main surface (22a). And a truncated pyramid-shaped light emitting element lens (24) made of a light transmitting resin. Light emitting element substrate (2
Two light emitting element wiring conductors (25, 26) spaced apart from each other are formed on one main surface (22a) of 2), and the back surface of the light emitting diode element (23) is formed on the main surface of one wiring conductor (25). Is fixed. An electrode formed on the upper surface of the light emitting diode element (23) is electrically connected to the other wiring conductor (26) through a thin lead wire (27). As shown in FIG. 6, cutouts (28, 29) are formed at both ends in the longitudinal direction of the light emitting element substrate (22). One ends of the light emitting element wiring conductors (25, 26) extend to the other main surface of the light emitting element substrate (22) through the notches (28) and (29), respectively. Two connection electrodes (30, 31) separated from each other are formed on the other main surface of the light emitting element substrate (22), and are respectively connected to one end of one or the other light emitting element wiring conductor (25, 26). . The light emitting element lens (24) is formed by a well-known transfer mold, and seals the light emitting diode element (23) and the fine lead wire (27). As shown in FIGS. 1 and 4, the first side surface (24a) of the light emitting element lens (24) that does not face the reflecting wall (13) of the outer lens (15) is connected to one main surface (11a) of the circuit board (11). ), The second side surface (24b) of the light emitting element lens (24) facing the reflection wall (13) is inclined at a first angle with respect to one main surface (11) of the circuit board (11).
Incline at a second angle greater than the first angle with respect to a).

The outer lens (1) of the light emitting element lens (24)
An inner lens (24d) is formed on the main surface on the 5) side (hereinafter referred to as the upper surface of the light emitting element lens). That is, a flat portion (24e) is formed along the outer edge of the upper surface of the light emitting element lens (24), an annular groove (24f) is formed inside the flat portion (24e), and the annular groove (24f) is formed inside the groove (24f). A spherical inner lens (24d) projecting hemispherically from the bottom is provided. The top of the inner lens (24d) is located on substantially the same plane as the flat portion (24e). The groove (24f) is flat (24e)
Has an annular inclined surface (24g) inclined from the inner edge of the inner lens to the bottom of the inner lens (24d). The inclined surface (24g) faces the side of the inner lens (24d). The flat part (24e) is used when the chip-type light emitting diode (12) is mounted on one main surface (11a) of the circuit board (11) by a suction jig to suck the chip-type light emitting diode (12). Acts as a surface. Also, by providing the inclined surface (24 g), in the manufacturing process of the chip-type light emitting diode (12), after the light emitting element lens (24) is molded by transfer molding or the like, the light emitting element lens (24) is Easy release from the mold. Further, a part of the light emitted from the light emitting element (23) and passing through the side of the inner lens (24d) is reflected on the inclined surface (24g) as shown in FIG. Since the optical path A is changed to the 15) side, the brightness of the semiconductor light emitting module can be increased.

As shown in FIGS. 1 and 2, the chip-type light emitting diode (12) is connected to the connection wiring conductor (16) on the circuit board (11) so as to bridge the intermittent region (19). It is fixed. That is, one connection electrode (30) and the other connection electrode (31) of the chip-type light emitting diode (12) are connected to the connection wiring conductor (16) on one side of the intermittent region (19) and the connection electrode on the other side, respectively. It is fixed to the connection wiring conductor (16). In the light-emitting diode module of FIG. 1, four chip-type light-emitting diodes are fixed to one connection wiring conductor (16) corresponding to the intermittent region (19) and electrically connected in series to each other. A total of 16 chip-type light emitting diodes (12) are arranged on the connection wiring conductor (16). In this embodiment, since the chip-type light emitting diode (12) that does not require external leads is used, the size and thickness of the entire module can be reduced. Also, by forming the inner lens (24d) on the chip type light emitting diode (12),
By the combination of the inner lens (24d) and the outer lens (15), appropriate light directivity is realized and an increase in light output is achieved. The second of the light emitting element lens (24)
The light extracted from the side (24b) of the outer lens (15)
The light output can be increased in that the light emitted from the light emitting diode element (23) can be effectively led out of the module because the direction of the light can be changed to the lens part (33) side by the reflective wall (13) of the light emitting diode. Can be.

An outer lens (15) according to the present invention is attached to a circuit board (11) to which a plurality of semiconductor light emitting devices (12) are fixed, and suppresses scattering of light emitted from the plurality of semiconductor light emitting devices (12). . The outer lens (15) is made of, for example, acrylic resin, polycarbonate or acrylic.
A lens body (15c) formed in a plate shape from a translucent material such as glass or a resin such as glycol carbonate resin (CR39) is provided. As shown in FIG. 4, the other main surface (15b) of the outer lens (15) is a flat surface, and the reflection wall (13) is formed integrally. As shown in FIGS. 7 and 8, a plurality of lens portions (33) projecting from one main surface (15a) of the lens body (15c) are formed integrally with the lens body (15c). The number of the lens portions (33) preferably corresponds to the number of the light emitting diodes (12). In the present embodiment, 16 lens portions (33) are provided which are equal to the number of the chip type light emitting diodes (12). As shown in FIG. 1, the lens portion (33) has a large curvature at a portion where light passes through the first side surface (24a) of the light emitting element lens (24), and as shown in FIG. A portion where light passes through the second side surface (24b) of the lens (24) has a small curvature. The lens portion (33) is formed to be long in the first direction shown in FIG. 2 and to be short in the second direction perpendicular to the first direction as viewed in plan. When the light-emitting element lens is formed to be long in the second direction, the effect of guiding the light guided through the first side surface (24a) of the light-emitting element lens (24) that is not easily deflected upward by the reflection wall (13) is impaired. Because it is In detail, FIGS.
As shown in FIG. 6, the lens portion (33) has an aspherical surface substantially in the shape of a half egg, and the ratio of the radii along the short axis (33a) and the long axis (33b) is 2: 2.1 to 2: 5 range. The curvature of the lens section (33) can be determined based on the design values shown in the graph of FIG. For example, the cross section of the lens portion (33) has a curvature of 2.9 mm in the major axis (33b) direction and a curvature of 1.9 mm in the minor axis (33a) direction. The connection surface of each lens part (33) is 4.5 mm × 3.0 mm with respect to the major axis (33b) -minor axis (33a).
It is continuously connected with the side cut until. The minimum thickness of the lens body (15c) is 0.5 mm. General tolerance is ± 0.1, one main surface (15a) of outer lens (15)
And the other main surface (15b) is mirror-finished (5S level).

In the outer lens (15) of the present invention, a leg (15d) projecting from the other main surface (15b) of the lens body (15c) and being mounted on the circuit board (11) is formed. FIG.
As shown in FIG. 11 to FIG. 11, in this embodiment, the legs (15
d), two lenses each on both sides of the lens body (15c), a total of four lenses are provided. A claw (15e) is formed at the tip of the leg (15d), and the claw (15e) is inserted into an opening (61) formed in the circuit board (11) and a peripheral wall ( Locked to 62). By inserting the claw (15e) formed at the tip of the leg (15d) into the opening (61) formed in the circuit board (11), the outer lens (15) can be snapped in one-touch using a snap action. It can be attached to the circuit board (11). Also, as shown in FIGS. 1 and 8, the lens body (15
The leg (15d) on one side of c) is formed in a curved shape. When mounting the outer lens (15), first insert the linear leg (15d) into one opening (61) of the circuit board (11) and insert the claw (15e) into the peripheral wall (61) of the opening (61). 62), and insert the curved leg (15d) into the other opening (61) in such a way as to draw an arc with this locked portion as a fulcrum, so that excessive stress is applied to the leg (15d). The outer lens (15) can be easily attached to the circuit board (11) without adding. Opening (61) of circuit board (11)
The left and right sides are formed symmetrically, and the lens body (15c) is
It can be mounted in the opening (61) of the circuit board (11) even when rotated by 0 degrees. Further, a projection (15f) projecting in the same direction as the leg (15d) is provided between the leg (15d), and the projection (1
5f) is attached to the hole (63) of the circuit board (11), and holds the lens body (15c) at an accurate position. Therefore, since the opening (61) of the circuit board (11) can be formed larger than the leg (15d) of the outer lens (15), the leg (15d) can be easily and easily inserted into the opening (61).

In the outer lens (15) of the present embodiment, the leg (15d) projecting from the other main surface (15b) of the lens body (15c) can be mounted on the circuit board (11), so that an outer enclosure is not required. Therefore, the semiconductor light emitting module can be easily mounted, and the size and thickness of the semiconductor light emitting module can be reduced. The lens section (33) has an aspherical surface of approximately a half egg, and has a short axis (33a) and a long axis (33).
Since the size ratio of the radius along b) is in the range of 2: 2.1 to 2: 5, the horizontally long directional characteristic required for the rectangular communication area of the ground unit can be obtained without significantly impairing the front light output. Obtainable. In addition, the other main surface (1
By forming the reflecting wall (13) in 5b), the luminous efficiency can be increased.

The effects of the embodiment of the present invention are as follows. (1) Since a chip type light emitting diode which does not require external leads is used, the whole module can be reduced in size and thickness. . (2) Since the outer lens is attached, the light emitted from the chip-type light emitting diode can be taken out to the outside, and the luminous efficiency and the light directivity can be improved. (3) Since the outer lens can be mounted on the circuit board and mounted, a module that can be easily assembled can be realized. (4) Since the reflecting wall composed of a part of the outer lens is arranged on the side surface of the chip type light emitting diode, the light radiated laterally from the light emitting element lens of the chip type light emitting diode is reflected upward by this reflecting wall, Since it can be taken out from the outer lens, it is advantageous in increasing the luminous efficiency also in this respect. (5) The outer lens is mounted on the circuit board by fitting, and a part of the outer lens doubles as a reflecting wall, so that the mounting is easy. (6) Since there is a reflecting wall disposed on the side surface of the chip-type light emitting diode, luminous efficiency can be increased.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows one principal surface (11a) of a circuit board (11).
By forming a light emitting circuit portion corresponding to the dotted line A portion 8 in FIG. 8 and forming a portion such as a switching circuit corresponding to the dotted line B portion in FIG. 18 on the other main surface (11b), further miniaturization is achieved. High integration can be achieved. In FIG.
(41) indicates an FET, (42) indicates a transistor, (43) indicates a Zener diode, (44) indicates a capacitor, (45) indicates an electrolytic capacitor, (46) indicates a diode, and (47) to (49) indicate resistors.

[0015]

As described above, according to the present invention, it is possible to obtain an outer lens for a semiconductor light emitting module which is small in size and high in luminance, and which can achieve an optimum increase in light directivity and light output.

[Brief description of the drawings]

FIG. 1 is a sectional view of a semiconductor light emitting module according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is a bottom view of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a sectional view of a semiconductor light emitting device applied to the semiconductor light emitting module of FIG. 1;

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a plan view of an outer lens.

FIG. 8 is a front view of the outer lens.

FIG. 9 is a bottom view of the outer lens.

FIG. 10 is a side view of the outer lens.

FIG. 11 is a sectional view taken along line CC of FIG. 8;

FIG. 12 is a partially enlarged view of FIG. 7;

13 is a sectional view taken along line DD of FIG.

14 is a sectional view taken along line EE of FIG.

FIG. 15 is a sectional view taken along line FF of FIG. 12;

FIG. 16 is a sectional view taken along line GG of FIG. 12;

FIG. 17 is a graph showing a design value of a curvature of a lens unit.

FIG. 18 is a circuit diagram showing an embodiment of the present invention.

FIG. 19 is a conceptual diagram showing bidirectional optical communication in VICS.

FIG. 20 is a sectional view of a conventional semiconductor light emitting module.

[Explanation of symbols]

(11) Circuit board (12) Light emitting diode (semiconductor light emitting device), (13) Reflective wall, (15) Outer lens, (15a) One main surface, (15b)・
The other main surface, (15c) ··· lens body, (15d) ···
Leg, (15e) ··· nail, (15f) · · · projection, (3
3) Lens part (33a) short axis, (33b) long axis, (61) opening, (62) peripheral wall, (63)
..Hole,

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-231117 (JP, A) JP-A-6-104488 (JP, A) JP-A 7-148972 (JP, A) 7160 (JP, U) Japanese Utility Model Showa 62-92504 (JP, U) Japanese Utility Model Application Hei 6-38268 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01L 33/00

Claims (5)

(57) [Claims] A lens body formed of a light-transmitting material in a plate shape; a plurality of lens portions integrally formed with the lens body and having an outer surface protruding from one main surface of the lens body; A leg portion protruding from the other main surface of the lens body and mounted on a circuit board to which the plurality of semiconductor light emitting devices are fixed, for suppressing the scattering of light emitted from the plurality of semiconductor light emitting devices. In the outer lens, the legs are provided on both sides of the lens body, and the legs on one side of the lens body have a curved shape. 2. The lens section has an aspherical surface and a substantially half-egg surface, and a ratio of radii along a short axis and a long axis is 2: 2.
2. The outer lens for a semiconductor light emitting module according to claim 1, wherein the ratio is in the range of 2.1 to 2: 5. 3. The outer lens for a semiconductor light emitting module according to claim 1, wherein a reflection wall is formed on the other main surface of the lens body. 4. The claw portion formed at the tip of the leg portion is inserted into an opening formed in the circuit board and is locked on a peripheral wall of the opening. Item 10. An outer lens for a semiconductor light emitting module according to item 9. 5. The semiconductor according to claim 1, wherein a projection formed between the legs is mounted in a hole of the circuit board to hold the lens body at a correct position. Outer lens for light emitting module.