JP4466083B2 - Ranging light source and ranging device - Google Patents

Description

  The present invention relates to a light emitting diode, a distance measuring light source and a distance measuring apparatus using the same.

For example, the light emitting diode is used as a light source of a distance measuring device for measuring a distance to a subject in an autofocus camera (see Patent Documents 1, 2, 3, and 4).
JP-A-6-265346 JP-A-7-35544 JP 7-63549 A Japanese Patent Laid-Open No. 2001-311619

  The light-emitting diode is arranged on one surface side of a pair of leads with a light-emitting diode chip (hereinafter referred to as an LED chip) with its emission surface facing away from the leads and connected to the pair of leads. The LED chip placement portion is molded by a mold body having a convex lens portion formed on the surface facing the emission surface of the LED chip, and the emitted light from the emission surface of the LED chip is the mold body. The convex lens part emits light with a smaller divergence angle.

  However, in the conventional light emitting diode, not only the light emitted from the LED chip but also the light emitted from the emission surface of the LED chip is refracted and emitted by the convex lens portion of the mold body in a direction in which the spread angle is reduced. Leaked light emitted from the peripheral surface of the LED chip in a direction opposite to the emission surface of the LED chip is reflected by the lead toward the convex lens portion, and the reflected light is reflected by the convex lens portion on the emission surface of the LED chip. Since the light is refracted in a direction different from the light emitted from the light and emitted as ghost light, the distance measuring device causes a measurement error due to the influence of the ghost light.

  The present invention provides a light emitting diode capable of emitting light containing almost no ghost light by eliminating the reflection of leakage light emitted in the direction opposite to the emitting surface of the LED chip toward the convex lens portion of the mold body. In addition, an object of the present invention is to provide a distance measuring light source and a distance measuring device that can perform distance measurement with high accuracy using the light emitting diode.

A distance measuring light source according to the present invention includes a pair of leads, and a light emitting diode chip that is disposed on one surface side of these leads with an emission surface facing away from the leads and connected to the pair of leads. And a convex lens portion that molds the arrangement portion of the light-emitting diode chip and emits light emitted from the light-emitting diode chip at the surface facing the light-emitting surface of the light-emitting diode chip with a reduced divergence angle. Of the light emitted from the light emitting diode chip, the mold body is formed and covers at least the pair of leads in the mold body, and the light emitting diode chip emits light in a direction opposite to the light emitting surface from the peripheral surface of the light emitting diode chip . a non-reflective light-shielding film for shielding the leakage light emitted toward the pair of leads is disposed on the exit side of the light emitting diode chip, the calling Characterized in that the diode chip and a projection lens that emits the corrected to the mold body parallel light the light divergence angle by the convex lens portion is emitted is refracted in a direction becomes small.

  The light shielding film is preferably provided over substantially the entire cross-sectional area of the mold body except for the LED chip portion.

  Furthermore, it is preferable that the light shielding film is formed by overlapping a portion on the LED chip side on a region excluding a portion corresponding to the light emitting portion of the LED chip on the emission surface of the LED chip.

  In addition, the light shielding film may be formed on the surface of the pair of leads on the LED chip side, and in that case, it is preferable to provide a light absorption film on the surface opposite to the convex lens portion forming surface of the mold body. .

Further, the distance measuring device according to the present invention includes a pair of leads, and a light emitting diode arranged on one surface side of these leads with an emission surface facing away from the leads and connected to the pair of leads. A convex lens part that molds a chip and an arrangement part of the light-emitting diode chip, and emits light emitted from the light-emitting diode chip on the surface facing the light-emitting surface of the light-emitting diode chip with a reduced divergence angle Of the light emitting diode chip that is provided so as to cover at least the entire pair of leads in the mold body, and the light emitting diode chip emits light from the peripheral surface of the light emitting diode chip in a direction opposite to the light emitting surface. A light-emitting diode comprising a non-reflective light-shielding film that blocks leakage light emitted toward the pair of leads, and the light-emitting diode A projection lens that is arranged on the emitting side and that is refracted from the light-emitting diode by the convex lens portion of the mold body in a direction in which the divergence angle is reduced, and that is emitted after correcting the emitted light to parallel light; and to the side of the light-emitting diode And an optical sensor that receives the return light emitted from the projection lens and reflected by the distance measuring object and outputs the signal.

  The distance measuring apparatus of the present invention includes a plurality of photoelectric conversion elements arranged in a direction intersecting with an emission direction of light from the projection lens in the optical sensor, and is emitted from the projection lens to be a distance measurement object. Photoelectric conversion of the return light incident point of the plurality of photoelectric conversion elements, the light reflected toward the optical sensor at an angle corresponding to the distance from the projection lens to the distance measuring object. It is suitable for a device that performs triangulation using a device that receives light by an element and outputs the signal.

  Furthermore, in the distance measuring device according to the present invention, the light-shielding film of the light-emitting diode has the LED chip-side portion overlapped with a region excluding the portion corresponding to the light-emitting portion of the LED chip on the emission surface of the LED chip. Preferably formed.

  In the distance measuring device of the present invention, the light-shielding film of the light emitting diode may be formed on the surface of the pair of leads on the LED chip side, and in that case, the convex lens portion forming surface of the mold body It is preferable to provide a light absorption film on the opposite surface.

A distance measuring light source according to the present invention includes a pair of leads, and a light emitting diode chip that is disposed on one surface side of these leads with an emission surface facing away from the leads and connected to the pair of leads. And a convex lens portion that molds the arrangement portion of the light-emitting diode chip and emits light emitted from the light-emitting diode chip at the surface facing the light-emitting surface of the light-emitting diode chip with a reduced divergence angle. Of the light emitted from the light emitting diode chip, the mold body is formed and covers at least the pair of leads in the mold body, and the light emitting diode chip emits light in a direction opposite to the light emitting surface from the peripheral surface of the light emitting diode chip . a non-reflective light-shielding film for shielding the leakage light emitted toward the pair of leads is disposed on the exit side of the light emitting diode chip, the calling Because the diode chip is provided with a projection lens that emits the corrected to the mold body parallel light the light divergence angle by the convex lens portion is emitted is refracted in a direction in which small, the exit surface of the LED chip Can eliminate the reflection of the leaked light emitted in the opposite direction by the lead and can emit light containing almost no ghost light.

That is, according to the distance measuring light source , out of the light emitted from the LED chip, the light emitted from the emission surface of the LED chip is refracted and emitted by the convex lens of the mold body in a direction in which the spread angle becomes smaller. However, since the leakage light emitted from the peripheral surface of the LED chip in the direction opposite to the emission surface is blocked by the light shielding film, the leakage light is reflected in the direction of the convex lens portion by the lead. Therefore, it is possible to emit light reflected by the lead of the leaked light, that is, light containing almost no ghost light.

  Further, it is preferable that the light shielding film is formed so that a portion on the LED chip side is overlapped with a region excluding a portion corresponding to the light emitting portion of the LED chip on the emitting surface of the LED chip. Accordingly, light can be emitted only from the portion corresponding to the light emitting portion of the emission surface of the LED chip, and light with less ghost light can be emitted.

In the distance measuring light source of this invention, the light shielding film may be formed on the surface of the pair of leads on the LED chip side, and in that case, by providing a light absorption film on the rear surface of the mold body, Reflection of leakage light emitted from the peripheral surface of the LED chip in a direction opposite to the emission surface by the lead and internal reflection on the rear surface of the mold body can be eliminated, and light with less ghost light can be emitted.

Further, the distance measuring light source of the present invention is arranged on the light emitting diode chip of the present invention and its emission side, and is refracted and emitted from the light emitting diode chip by a convex lens portion of the mold body in a direction in which the spread angle becomes smaller. Since the projection lens emits light after correcting the light into parallel light, the light emitting diode emits light containing almost no ghost light, and the light is corrected into parallel light by the projection lens and emitted. Therefore, it is possible to perform distance measurement with high accuracy by using the distance measuring light source for the distance measuring device.

Further, the distance measuring device according to the present invention includes a pair of leads, and a light emitting diode arranged on one surface side of these leads with an emission surface facing away from the leads and connected to the pair of leads. A convex lens part that molds a chip and an arrangement part of the light-emitting diode chip, and emits light emitted from the light-emitting diode chip on the surface facing the light-emitting surface of the light-emitting diode chip with a reduced divergence angle Of the light emitting diode chip that is provided so as to cover at least the entire pair of leads in the mold body, and the light emitting diode chip emits light from the peripheral surface of the light emitting diode chip in a direction opposite to the light emitting surface. A light-emitting diode comprising a non-reflective light-shielding film that blocks leaked light emitted toward the pair of leads, and A projection lens that is arranged on the emitting side and that is refracted from the light-emitting diode by the convex lens portion of the mold body in a direction in which the divergence angle is reduced, and that is emitted after correcting the emitted light to parallel light; and to the side of the light-emitting diode And a light sensor that receives the return light that is emitted from the projection lens and reflected by the object to be measured and outputs the signal, and thus hardly contains ghost light from the light emitting diode. It is possible to emit light, correct the light into parallel light by the projection lens, emit the light, and project the light onto the distance measuring object. Therefore, the return light reflected by the distance measuring object is reflected by the optical sensor. The distance to the distance measuring object can be measured with high accuracy by receiving light.

  The distance measuring apparatus of the present invention includes a plurality of photoelectric conversion elements arranged in a direction intersecting with an emission direction of light from the projection lens in the optical sensor, and is emitted from the projection lens to be a distance measurement object. Photoelectric conversion of the return light incident point of the plurality of photoelectric conversion elements, the light reflected toward the optical sensor at an angle corresponding to the distance from the projection lens to the distance measuring object. It is suitable for a device that performs triangulation using a device that receives light by an element and outputs the signal, and according to the distance measuring device of the present invention, the accuracy of the triangulation can be remarkably increased. .

  Furthermore, in the distance measuring device according to the present invention, the light-shielding film of the light-emitting diode has the LED chip-side portion overlapped with a region excluding the portion corresponding to the light-emitting portion of the LED chip on the emission surface of the LED chip. It is preferable to form, and by doing so, light is emitted only from the portion corresponding to the light emitting portion of the emission surface of the LED chip, light with less ghost light is emitted from the light emitting diode, and High-precision distance measurement can be performed.

  In the distance measuring device of the present invention, the light-shielding film of the light emitting diode may be formed on the surface of the pair of leads on the LED chip side, and in that case, the convex lens portion forming surface of the mold body By providing a light-absorbing film on the opposite surface, the light emission without the reflection by the lead of the leaked light emitted from the peripheral surface of the LED chip in the direction opposite to the emission surface and the internal reflection at the rear surface of the mold body is eliminated. Light with less ghost light can be emitted from the diode, and more accurate distance measurement can be performed.

  1 and 2 are a sectional view and a partially cutaway front view of a light emitting diode according to a first embodiment of the present invention.

  The light-emitting diode 1 is disposed on a pair of leads 2 and 3 and on one surface side of the leads 2 and 3 with the emission surface 4a facing away from the leads 2 and 3, and the pair of leads The LED chip 4 connected to 2 and 3 and the arrangement part of the LED chip 4 are molded, and the light emitted from the light emission surface 4a of the LED chip 4 is applied to the surface facing the light emission surface 4a of the LED chip 4. A mold body 6 formed with a convex lens portion 7 that emits light with a reduced divergence angle, and a surface of the pair of leads 2, 3 on the LED chip 4 side are provided in the mold body 6, and the LED Of the light emitted by the chip 4, a non-reflective light-shielding film 8 is provided to block leaked light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface.

  The pair of leads 2 and 3 is made of an iron-based metal having a surface plated with solder, and one of the leads 2 and 3 is connected to one end of the LED chip 4. A chip mounting portion having an area slightly larger than the planar shape is formed.

  Although the structure of the LED chip 4 is not shown, an electrode is provided on each of the p-layer and n-layer of a chip-like semiconductor in which a dot-like light-emitting portion consisting of a pn junction surface is formed at the center on one surface side. The surface on the light emitting portion side of the chip-like semiconductor is an emission surface 4a.

  The LED chip 4 is bonded to the chip mounting portion formed on one end of the one lead 2 with the opposite surface to the light emitting surface 4a, and one electrode is attached to one end of the one lead 2. The other electrode is connected to one end portion of the other lead 3 via a lead wire 5.

  The mold body 6 is made of a transparent resin such as an epoxy resin, and the axis of the convex lens portion 7 has an emission optical axis from the emission surface of the LED chip 4 (perpendicular to the emission surface and of the light emitting portion a). Line that passes through the center).

  On the other hand, the non-reflective light-shielding film 8 has, for example, substantially the same outer shape as the cross-sectional shape in the direction orthogonal to the axis of the convex lens portion 7 in the portion other than the convex lens portion 7 of the mold body 6. The light-shielding film 8 is formed of a black light-absorbing film in which an opening that closely fits to the outer periphery of the LED chip 4 is formed. The light-shielding film 8 is formed by fitting the LED chip 4 into the opening. The leads 2 and 3 are superimposed on the surface of the LED chip 4 side, and are molded by the mold body 6 together with the LED chip 4 and one ends of the leads 2 and 3.

  In the light emitting diode 1, the LED chip 4 is disposed on one surface side of the pair of leads 2 and 3, and the emitting surface 4a thereof is disposed in the direction opposite to the leads 2 and 3, and the LED chip 4 is disposed. Are molded by a mold body 6 in which a convex lens portion 7 is formed on a surface facing the emission surface 4a of the LED chip 4, and the LED chip 4 side of the pair of leads 2 and 3 is further formed in the mold body 6. A non-reflective light-shielding film 8 is provided to block leakage light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a out of the light emitted from the LED chip 4. Therefore, the leakage light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a is not reflected by the leads 2 and 3, and light containing almost no ghost light from the convex lens portion 7 is removed. It is possible to Cum.

  That is, FIG. 3 shows the light emission state from the light emitting diode 1 of the above embodiment, and FIG. 4 shows the light emission state from the light emitting diode 1a not provided with the non-reflective light shielding film 8.

  First, the light emission from the light emitting diode 1a that does not include the non-reflective light shielding film 8 shown in FIG. 4 will be described. The light emitting diode 1a is the light emitting surface of the LED chip 4 out of the light emitted from the LED chip 4. The light emitted from 4a is not only refracted and emitted by the convex lens portion 7 of the molded body 6 in a direction in which the divergence angle is reduced as shown by the solid line in FIG. Leaked light emitted in the direction opposite to the emission surface 4 a of the chip 4 is reflected in the direction of the convex lens portion 7 by the leads 2 and 3 as indicated by broken lines in FIG. 4, and the reflected light is reflected by the convex lens portion 7. The light is refracted in a direction different from the light emitted from the emission surface 4a of the LED chip 4 and emitted as ghost light.

  Although not shown in FIG. 4, leakage light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4 a passes through the side of the leads 2 and 3 and the mold body. There is also light directed toward the rear surface, that is, the surface opposite to the convex lens portion forming surface, and the light emitting diode 1a that does not include the non-reflective light-shielding film 8 reflects the inner surface of the light-emitting diode 1a on the rear surface of the mold body 6 The reflected light is refracted by the convex lens portion 7 in a direction different from the light emitted from the emission surface 4a of the LED chip 4 and emitted as ghost light. .

  On the other hand, in the light-emitting diode 1 of the above embodiment, the light emitted from the emission surface 4a of the LED chip 4 out of the light emitted from the LED chip 4 is a convex lens of the mold body 6 as shown by the solid line in FIG. 7 is refracted and emitted in the direction in which the divergence angle becomes smaller, but the leaked light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a is blocked by the non-reflective light shielding film 8, The leaked light is not reflected by the leads 2 and 3 and is not emitted from the convex lens unit 7, and therefore, the reflected light of the leaked light by the leads 2 and 3, that is, light containing almost no ghost light is transmitted to the convex lens unit. 7 can be emitted.

  Moreover, since the light-emitting diode 1 is provided with the light-shielding film 8 so as to cover substantially the entire portion of the pair of leads 2 and 3 in the molded body 6, the light-emitting diode 4 extends from the peripheral surface of the LED chip 4 to the emission surface 4 a. Reflection of the leaked light emitted in the opposite direction to the leads 2 and 3 is almost completely eliminated, and light with less ghost light can be emitted.

  Further, the light-emitting diode 1 has a cross-sectional shape of the portion other than the convex lens portion 7 in the direction orthogonal to the axis of the convex lens portion 7 of the portion other than the convex lens portion 7 of the mold body 6. Substantially the same as the cross-sectional shape in the direction orthogonal to the axis of the convex lens portion 7), and the light-shielding film 8 is provided over substantially the entire cross-sectional area of the mold body 6 except for the LED chip 4 portion. Of the leaked light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a, it is possible to eliminate internal reflection on the rear surface of the mold body of the light passing through the sides of the leads 2 and 3, Therefore, light with less ghost light can be emitted.

  In the first embodiment, the non-reflective light shielding film 8 is provided so as to cover substantially the entire portion of the pair of leads 2 and 3 in the mold body 6. Of the leaked light that is emitted in the direction opposite to the emission surface 4 a of the LED chip 4 and reflected by the leads 2 and 3, most of the reflected light directed to the convex lens portion 7 of the mold body 6 is the leads 2 and 3. The light-shielding film 8 is provided on the peripheral portion of the LED chip 4 so as to cover the surface of the pair of leads 2 and 3 on the LED chip 4 side. In this case, too, reflection of the leaked light in the direction of the convex lens portion 7 by the leads 2 and 3 can be almost eliminated, and light with little ghost light can be emitted.

  5 and 6 are a sectional view and a partially cutaway front view of a light emitting diode according to a second embodiment of the present invention. The light emitting diode 1 of this embodiment has a non-reflective light shielding film 8 and a molded body 6. Has an outer shape that is substantially the same as the cross-sectional shape of the portion other than the convex lens portion 7 (the cross-sectional shape in the direction orthogonal to the axis of the convex lens portion 7), and an opening that fits closely to the outer periphery of the LED chip 4 is formed at the top. The light-shielding film 8 is formed in a region near the top, that is, a region corresponding to the peripheral portion of the LED chip 4, and the surface on the LED chip 4 side of the pair of leads 2 and 3. It is arranged to cover.

  In this embodiment, a lead-through hole is provided in each of the portions of the inclined surface of the pyramid-shaped or conical light-shielding film 8 that intersects the pair of leads 2 and 3, and the light-shielding film 8 is connected to the lead-through film. The leads 2 and 3 are inserted through the holes.

  Since the light emitting diode 1 covers a portion of the pair of leads 2 and 3 in the vicinity of the LED chip 4 with a non-reflective light-shielding film 8, the LED chip 4 has a light emitting surface 4a extending from the peripheral surface of the LED chip 4. Substantially eliminates reflection of the leaked light emitted in the opposite direction by the leads 2 and 3, and makes the outer shape of the light shielding film 8 substantially the same as the cross-sectional shape of the part other than the convex lens portion 7 of the mold body 6. Since the LED chip 4 part is provided over substantially the entire cross-sectional area of the mold body 6, the lead out of the leaked light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4 a. It is possible to eliminate internal reflection of the light that has passed through the sides of the mold 3 at the rear surface of the mold body. Therefore, it is possible to emit light containing almost no ghost light from the convex lens portion 7. That.

  FIG. 7 is a cross-sectional view of a light emitting diode according to a third embodiment of the present invention. In the light emitting diode 1 of this embodiment, the outer shape of the non-reflective light-shielding film 8 is the portion of the molded body 6 other than the convex lens portion 7. The cross-sectional shape of the portion other than the convex lens portion 7 in the direction orthogonal to the axis of the convex lens portion 7 is made substantially the same, and the light shielding film 8 covers substantially the entire portion of the pair of leads 2 and 3 in the mold body 6. And a portion of the light-shielding film 8 on the LED chip 4 side is formed so as to overlap an outer peripheral region of the light emission surface 4a of the LED chip 4 excluding a portion corresponding to the light emitting portion at the center of the LED chip 4. It is a thing.

  According to the light-emitting diode 1 of this embodiment, the reflection of the leakage light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a by the leads 2 and 3 and the lead 2 of the leakage light. , 3, the inner reflection of the light on the rear surface of the mold body is eliminated, and the light is emitted only from the portion corresponding to the light emitting portion of the emission surface 4 a of the LED chip 4. Light can be emitted.

  That is, the LED chip 4 directly emits the light from the light emitting portion from the light emitting surface 4a, and reflects the light that travels from the light emitting portion into the LED chip on the surface opposite to the light emitting surface 4a. The light is incident on the emission surface 4a by the reflection on the surface of the lead 2 and the internal reflection on the peripheral surface of the LED chip 4, and is emitted from the emission surface 4a. The light is directly emitted from the emission surface 4a. There is also stray light that is emitted in a direction greatly deviated, and this stray light is refracted in a direction different from the light directly emitted from the emission surface 4a of the LED chip 4 by the convex lens portion 7 of the mold body 6 to become ghost light. .

  However, in the light-emitting diode 1 of this embodiment, the portion of the light-shielding film 8 on the LED chip 4 side is the region excluding the portion corresponding to the light-emitting portion of the LED chip 4 on the emission surface 4a of the LED chip 4. Since they are formed in an overlapping manner, light can be emitted only from the portion corresponding to the light emitting portion of the emission surface 4a of the LED chip 4, and therefore, the emission of the stray light is almost eliminated, and light with less ghost light is generated. Can be emitted.

  FIG. 8 is a cross-sectional view of a light emitting diode according to a fourth embodiment of the present invention. In the light emitting diode 1 of this embodiment, a non-reflective light shielding film 8 is formed on the LED chip 4 side of a pair of leads 2 and 3. The surface of the mold body 6 is provided so as to cover substantially the entire portion of the mold body 6, and the light absorption film 9 is provided on the entire rear surface of the mold body. According to the light emitting diode 1, the periphery of the LED chip 4 is provided. Reflection of leakage light emitted from the surface in the direction opposite to the emission surface 4a by the leads 2 and 3 and internal reflection at the rear surface of the mold body can be eliminated, and light with less ghost light can be emitted.

  The light emitting diode 1 is used as a light source of a distance measuring device for measuring a distance to a distance measuring object (a subject in the case of an auto focus camera) such as a distance measuring device of an auto focus camera.

  FIG. 9 shows an embodiment of a distance measuring light source according to the present invention. The distance measuring light source of this embodiment is disposed on the light emitting diode 1 of the first embodiment and on the emission side thereof, and emits the light. A projection lens 10 that emits light that is emitted from the emission surface 4a of the LED chip 4 of the diode 1 and is refracted in a direction in which the divergence angle is reduced by the convex lens portion 7 of the mold body 6 to be parallel light; It is provided.

  The distance measuring light source is used in an infrared distance measuring device for measuring a distance to a subject mounted on an autofocus camera, and the LED chip 4 of the light emitting diode 1 emits infrared light. A chip-like semiconductor is provided.

  Since the distance measuring light source has the projection lens 10 disposed on the light emitting diode 1 emitting side of the first embodiment, the light emitting diode 1 emits light containing almost no ghost light. Light can be emitted after being corrected to parallel light by the projection lens 10. Therefore, by using this distance measuring light source for the distance measuring device, distance measurement with high accuracy can be performed.

  That is, FIG. 10 shows a light source for distance measurement using the light emitting diode 1a not provided with the non-reflective light shielding film 8, and the light emitting diode 1a not provided with the non-reflective light shielding film 8 is shown in FIG. As described above, the normal light emitted from the emission surface 4a of the LED chip 4 and the spread angle of which is reduced by the convex lens portion 7 of the mold body 6 is emitted in the direction opposite to the emission surface 4a from the peripheral surface of the LED chip 4. The reflected light of the leaked light is emitted as ghost light refracted by the convex lens portion 7 in a direction different from the normal light.

  For this reason, in this distance measuring light source, the regular light from the light emitting diode 1a is not only corrected by the projection lens 10 into parallel light as shown by the solid line in FIG. 10, but also emitted from the light emitting diode 1a. Light is emitted from the projection lens 10 in a direction different from the parallel light as indicated by a broken line in FIG. 10, causing a measurement error due to the influence of the ghost light in the distance measuring device.

  On the other hand, in the distance measuring light source in which the projection lens 10 is arranged on the emission side of the light emitting diode 1 of the first embodiment, the emission light from the light emitting diode 1 contains almost ghost light as shown in FIG. Since this light is corrected into parallel light by the projection lens 10 and emitted as shown by the solid line in FIG. 9, this distance measuring light source is used in the distance measuring device, so that the distance is high. Measurements can be made.

  The distance measuring light source of the above embodiment uses the light emitting diode 1 of the first embodiment shown in FIGS. 1 to 3, and the light emitting diode 1 is shown in FIGS. The second embodiment, the third embodiment shown in FIG. 7, and the fourth embodiment shown in FIG. 8 may be used. In this case, the distance measuring light source is used in the distance measuring device. Highly accurate distance measurement can be performed.

  The distance measuring light source of the present invention is not limited to the distance measuring device of the autofocus camera, but can also be used for the light source of other distance measuring devices.

  FIG. 11 shows an embodiment of the distance measuring device according to the present invention. This distance measuring device is disposed on the light emitting diode 1 of any one of the first to fourth embodiments and on the emission side thereof. A projection lens 10 that emits light that is emitted from the emission surface 4a of the LED chip 4 of the light-emitting diode 1 and refracted in a direction in which the divergence angle is reduced by the convex lens portion 7 of the mold body 6 to be parallel light; An optical sensor 11 which is arranged on the side of the light emitting diode 1 with a sufficient interval, receives the return light emitted from the projection lens 10 and reflected by the distance measuring object A, and outputs the signal; A distance measuring circuit 14 for determining a distance to the distance measuring object A based on an output signal from the optical sensor 11.

  The distance measuring device of this embodiment is an infrared distance measuring device mounted on an autofocus camera, and the LED chip 4 of the light emitting diode 1 includes a chip-like semiconductor that emits infrared light.

  In the distance measuring apparatus, the optical sensor 11 has a plurality of photoelectric conversion elements, for example, photodiodes 12 on one surface, in a direction intersecting with an emission direction of light (parallel light) from the projection lens 10. It is formed by arranging closely in one row, is emitted from the projection lens, is reflected by a distance measuring object (hereinafter referred to as subject) A, and is projected from the projection lens 10 to the optical sensor 11. Return light incident from an angular direction corresponding to the distance to A is received by the photodiode 12 at the incident point of the return light among the plurality of photodiodes 12, and the signal is output.

  The optical sensor 11 has its photodiode forming surface directed in a direction in which the light emitted from the projection lens 10 is directed, and the photodiode forming surface is perpendicular to the axis O of the light emitted from the projection lens 10. Accordingly, the plurality of photodiodes 12 of the optical sensor 11 are arranged in a direction orthogonal to the axis O of the light emitted from the projection lens 10.

  A sensor side lens 13 that collects the return light reflected by the subject A and makes it incident on the light receiving surface of the photodiode 12 is provided on the light incident side of the optical sensor 11, that is, in front of the photodiode forming surface. Has been placed.

  This distance measuring device performs triangulation, and projects the light emitted from the light emitting diode 1, converted into parallel light by the projection lens 10, and emitted from the projection lens 10 toward the subject A. The light reflected by the subject A and returned toward the photosensor 11 from the angle direction corresponding to the distance from the projection lens 10 to the subject A is, among the plurality of photodiodes 12 of the photosensor 11, Is received by the photodiode 12 located at the incident point of the return light, and the signal is output from the optical sensor 11 to the distance measuring circuit 14.

  The return light reflected by the subject A is collected by the sensor-side lens 13 and is incident on the photodiode 12 positioned at the return light incident point among the plurality of photodiodes 12 of the optical sensor 11. To do.

  In FIG. 11, a solid line indicates an optical path when the distance from the projection lens 10 to the subject A is short, and a chain line indicates an optical path when the distance from the projection lens 10 to the subject A is long. When the distance to A is short, the return light reflected by the subject A is incident on the photodiode 12 near the light emitting diode 1 of the optical sensor 11, and the distance from the projection lens 10 to the subject A is as follows. When it is long, the return light reflected by the subject A is incident on the photodiode 12 on the side farther from the light emitting diode 1 of the light sensor 11.

  Then, the optical sensor 11 outputs a signal corresponding to the position of the photodiode 12 that has received the return light among the plurality of photodiodes 12 to the distance measuring circuit 14.

  On the other hand, the distance measurement circuit 14 is preset with the distance data from the axis O of the light emitted from the projection lens 10, that is, the subject projection light, to the position where the photosensor 11 is arranged. Based on the output signal from the optical sensor 11, the distance from the axis O to the return light incident point of the optical sensor 11 on the line orthogonal to the axis O of the subject projection light, and the optical sensor 11 The incident angle of the return light is obtained, the distance to the subject A is determined from these distances and angles based on the principle of triangulation, and the distance measurement data is output to a lens focus adjustment unit (not shown).

  The distance measuring device includes the light emitting diode 1 according to any one of the first to fourth embodiments and light emitted from the light emitting diode 1 by being refracted by the convex lens portion 7 of the mold body 6 so that the divergence angle is reduced. The projection lens 10 that emits light after correcting the light into parallel light, and the return light that is disposed on the side of the light emitting diode 1 and that is emitted from the projection lens 10 and reflected by the distance measuring object A receives the signal. Therefore, the light emitting diode 1 emits light containing almost no ghost light, and the light is corrected into parallel light by the projection lens 10 and emitted. Accordingly, the distance measurement to the subject A is performed with high accuracy by causing the optical sensor 11 to receive the return light reflected by the subject A. Door can be.

  That is, the distance measuring apparatus of this embodiment includes a plurality of photodiodes 12 arranged in a direction intersecting the light emitting direction of the light from the projection lens 10 in the optical sensor 11, and is emitted from the projection lens 10. The return light reflected by the subject A and incident on the optical sensor 11 from an angle direction corresponding to the distance from the projection lens 10 to the subject A is converted into the return light of the plurality of photodiodes 12. Triangular distance measurement is performed by using the light received by the photodiode 12 at the incident point and outputting the signal. In this triangular distance measurement, the light is emitted from the light emitting diode 1 and is applied to the subject A by the projection lens 10. When the projected light includes ghost light, the ghost light affects the distance measurement accuracy. According to the distance measuring apparatus, the light emitting diode 1 Therefore, it is possible to emit light that contains almost no ghost light, correct the light into parallel light by the projection lens 10, emit the light, and project it onto the subject A. Therefore, the accuracy of the triangulation is greatly improved. can do.

  In the distance measuring device, the light-shielding film 8 of the light emitting diode 1 covers substantially the entire portion of the pair of leads 2 and 3 in the mold body 6 as in the first embodiment shown in FIGS. It is desirable to cover the light emitting diode so that the reflection of the leaked light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a is almost completely eliminated by the light emitting diode. It is possible to perform distance measurement with higher accuracy by emitting light with less ghost light from 1.

  Further, in the distance measuring device, the light shielding film 8 of the light emitting diode 1 is substantially the same as the cross section of the molded body 6 except for the LED chip 4 portion as in the second embodiment shown in FIGS. It is desirable to provide the whole, and by doing so, the mold of the light that has passed through the sides of the leads 2 and 3 out of the leaked light emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a. There is no inner surface reflection on the rear surface of the body, that is, the surface opposite to the convex lens portion forming surface, and light with less ghost light can be emitted from the light emitting diode 1 to perform more accurate distance measurement.

  Furthermore, in the distance measuring device, the light shielding film 8 of the light emitting diode 1 is formed on the LED chip 4 side of the light emitting surface 4a of the LED chip 4 as in the third embodiment shown in FIG. Preferably, the LED chip 4 is formed so as to overlap with a region excluding the portion corresponding to the light emitting portion, and by doing so, light is emitted only from the portion corresponding to the light emitting portion of the emission surface 4a of the LED chip 4. The light can be emitted and light with less ghost light can be emitted from the light emitting diode 1, so that the distance can be measured with higher accuracy.

  In the distance measuring apparatus, the light shielding film 8 of the light emitting diode 1 is formed on the surface of the pair of leads 2 and 3 on the LED chip 4 side as in the fourth embodiment shown in FIG. In this case, the light leakage film 9 is emitted from the peripheral surface of the LED chip 4 in the direction opposite to the emission surface 4a by providing the light absorbing film 9 on the surface opposite to the convex lens portion forming surface of the mold body 6. Thus, the reflection by the leads 2 and 3 and the inner surface reflection at the rear surface of the mold body are eliminated, and light with less ghost light is emitted from the light emitting diode 1, and more accurate distance measurement can be performed.

  Although the distance measuring device shown in FIG. 11 performs triangulation, the present invention is refracted and emitted from the light emitting diode 1 by the convex lens portion 7 of the mold body 6 in a direction in which the divergence angle becomes smaller. The light is corrected into parallel light by the projection lens 10 and emitted, and the return light reflected by the subject (object for distance measurement) A is received by the optical sensor arranged on the side of the light emitting diode 1 to emit the light. The present invention can also be applied to a distance measuring device that performs time difference ranging that determines the distance to the subject A based on the time difference between the light emission from the diode 1 and the return light incident on the optical sensor.

  Further, the distance measuring device of the present invention is not limited to the distance measuring device of the autofocus camera, but can be applied to other distance measuring devices.

1 is a cross-sectional view of a light emitting diode showing a first embodiment of the present invention. FIG. 3 is a partially cut front view of the light emitting diode of the first embodiment. The figure which shows the emission state of the light from the light emitting diode 1 of a 1st Example. The figure which shows the emission state of the light from the light emitting diode which is not provided with a non-reflective light shielding film. Sectional drawing of the light emitting diode which shows 2nd Example of this invention. The partial cutaway front view of the light emitting diode of 2nd Example. Sectional drawing of the light emitting diode which shows the 3rd Example of this invention. Sectional drawing of the light emitting diode which shows 4th Example of this invention. The side view which shows one Example of the light source for ranging of this invention. The side view of the light source for ranging using the light emitting diode which is not provided with a non-reflective light shielding film. The figure which shows one Example of the distance measuring device of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Light emitting diode, 2, 3 ... Lead, 4 ... LED chip, 4a ... Outgoing surface, 5 ... Lead wire, 6 ... Molding body, 7 ... Convex lens part, 8 ... Non-reflective light shielding film, 9 ... Light absorption film, DESCRIPTION OF SYMBOLS 10 ... Projection lens, 11 ... Optical sensor, 12 ... Photodiode (photoelectric conversion element), 13 ... Sensor side lens, 14 ... Ranging circuit, A ... Subject (ranging object).

Claims (7)

A pair of leads, a light emitting diode chip connected to the pair of leads, the light emitting diode chip disposed on one surface side of these leads with the emission surface facing away from the leads, and the arrangement portion of the light emitting diode chip And a mold body in which a convex lens portion is formed on the surface facing the emission surface of the light-emitting diode chip and the emitted light from the emission surface of the light-emitting diode chip is emitted with a reduced divergence angle, and at least the It provided to cover the the upper pair of leads entire mold body, of light the light emitting diode chip is emitted, the light emitting diode and the emitting surface from the circumferential surface of the chip towards on the opposite direction of the pair of lead exit a non-reflective light-shielding film for shielding the leakage light, the disposed on the exit side of the light emitting diode chip, before the light emitting diode chips Ranging source, characterized by comprising a projection lens that emits the corrected light divergence angle by the convex lens portion is emitted is refracted in the direction of smaller mold member into parallel light. The light-shielding film is formed by overlapping a portion on the light-emitting diode chip side on a region excluding a portion corresponding to a light-emitting portion of the light-emitting diode chip on an emission surface of the light-emitting diode chip. The light source for ranging according to 1. The light shielding film is formed on a surface of the pair of leads on the light emitting diode chip side, and a light absorbing film is provided on a surface opposite to the convex lens portion forming surface of the mold body. The light source for distance measurement as described. A pair of leads, a light emitting diode chip connected to the pair of leads, the light emitting diode chip disposed on one surface side of these leads with the emission surface facing away from the leads, and the arrangement portion of the light emitting diode chip And a mold body in which a convex lens portion is formed on the surface facing the emission surface of the light-emitting diode chip and the emitted light from the emission surface of the light-emitting diode chip is emitted with a reduced divergence angle, and at least the It provided to cover the the upper pair of leads entire mold body, of light the light emitting diode chip is emitted, the light emitting diode and the emitting surface from the circumferential surface of the chip towards on the opposite direction of the pair of lead exit A light emitting diode including a non-reflective light shielding film that blocks the leaked light,
A projection lens that is disposed on the light emission side of the light emitting diode, corrects the light emitted from the light emitting diode by the convex lens portion of the mold body and is refracted in a direction in which the divergence angle is reduced, and emits the parallel light;
A distance measuring device, comprising: a light sensor disposed on a side of the light emitting diode, receiving a return light emitted from the projection lens and reflected by a distance measuring object, and outputting the signal. . The optical sensor includes a plurality of photoelectric conversion elements arranged in a direction intersecting with an emission direction of light from the projection lens, is emitted from the projection lens, is reflected by a distance measuring object, and is measured from the projection lens. Light returning toward the optical sensor at an angle corresponding to the distance to the distance object is received by the photoelectric conversion element at the incident point of the return light among the plurality of photoelectric conversion elements, and the signal is output. The distance measuring device according to claim 4 . The light-shielding film of the light-emitting diode is formed by overlapping a portion on the light-emitting diode chip side on a region excluding a portion corresponding to the light-emitting portion of the light-emitting diode chip on the light-emitting diode chip exit surface. The distance measuring device according to claim 4 or 5 . Shielding film of the light-emitting diode, and a light absorbing film is provided on the opposite surface to the light emitting diode is formed on the chip side surface, the convex lens forming surface of the mold of the pair of leads claims Item 6. The distance measuring device according to Item 4 or 5 .

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