JP2019009236A - Optical module - Google Patents

Abstract

To provide an optical module capable of welding a barrel and an optical component by irradiation with a laser beam from an outer periphery of the barrel while checking from the outside.SOLUTION: An optical module includes a barrel and an optical component inserted from an end part of the barrel. The barrel is provided with one or more openings in an area where a side surface of the optical component is in contact with the inner wall of the barrel. Some area of the optical component exposed from the openings is welded to the barrel in contact with the some area.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an optical module in which optical components such as a light emitting element and a lens are held in a lens barrel.

  In order to make light emitted from a light emitting element enter an optical component such as a lens or an optical fiber with high efficiency, the optical component may be aligned and fixed in a lens barrel and used as an optical module. . By adopting an optical module structure, attachment to other devices becomes easy, and convenience is improved.

  For example, in Patent Document 1, the end surface of the light incident / exit window frame of the package in which the light emitting element or the like is disposed is abutted with the end surface of the holder of the optical fiber coupling lens, and the periphery of the butted portion is changed from the periphery to the outer periphery. An optical module welded by irradiating YAG laser light is disclosed. Also, if the part to be welded is gold-plated, the gold melts into the alloy melted by welding and the mounting strength becomes insufficient, so the gold plating is removed by cutting or chemical etching in advance. It is also disclosed to do.

Japanese Patent Laying-Open No. 2005-49588 (particularly, paragraphs 0045 and 0079, FIG. 1C)

  In the technique of Patent Document 1, since the end surface of the frame portion of the light incident / exit window is abutted with the end surface of the holder of the optical fiber coupling lens and welded, the abutting portion can be confirmed from the appearance. Moreover, since the welding part is welded by irradiating the YAG laser from the outer periphery, the welding part can also be confirmed from the outside.

  However, the structure of the optical module is not limited to the joint part as in Patent Document 1, for example, by inserting a packaged light emitting element and a lens from both ends in the lens barrel, There are optical modules that are structured to be aligned and fixed with respect to the lens barrel. In this case, it is difficult to confirm the position of the inserted light-emitting element or lens in the lens barrel from the outer peripheral surface, and the position of the light-emitting element or lens can be confirmed with information that can be grasped from the end of the lens barrel. Will do. In addition, when the inserted light emitting element package and the lens are welded to the lens barrel, it is conceivable that the light emitting element package or lens and the end surface of the lens barrel are fillet welded with a YAG laser at the end of the lens barrel. In laser welding, it is necessary to irradiate the laser beam by holding the end of the lens barrel toward the YAG laser using a jig or the like. In order to weld fillet between the light emitting element package and the lens at both ends of the lens barrel, after placing one end of the lens barrel facing the YAG laser and performing welding, the lens barrel is inverted and the other It is necessary to re-hold the end of the laser beam so that it faces the YAG laser.

  In addition, by performing lap through welding from the outer peripheral surface of the lens barrel, it is possible to weld the lens barrel and the light emitting element package by YAG laser irradiation from the outer peripheral surface. The state of the part cannot be observed from the outer periphery. For this reason, it is difficult to inspect the welding quality. In addition, when the optical module is attached to another device, if forces opposite to each other in the axial direction are applied to the lens barrel and the light emitting device package, a shear stress is applied to the lap through weld and the load on the welded portion is reduced. growing.

  Further, if the gold plating is previously removed by cutting or chemical etching in order to prevent the gold plating from being mixed into the welded portion, the number of steps increases, resulting in a longer manufacturing time and a higher manufacturing cost.

  An object of the present invention is to provide an optical module capable of welding a lens barrel and an optical component by irradiating a laser beam from the outer periphery of the lens barrel while confirming from the outside.

  In order to achieve the above object, the optical module of the present invention includes a lens barrel and an optical component inserted from the end of the lens barrel. The lens barrel is provided with one or more openings in a region where the side surface of the optical component is in contact with the inner wall of the lens barrel. A partial region of the optical component exposed from the opening is welded to a lens barrel in contact with the partial region.

  According to the present invention, the optical component can be irradiated with the laser beam through the opening of the lens barrel, so that the lens barrel and the optical component can be welded by laser light irradiation from the outer periphery of the lens barrel while confirming from the outside.

(A), (b) and (c) are respectively a sectional view, a side view and a bottom view of the optical module of the first embodiment. (A), (b) and (c) are respectively a sectional view, a side view and a bottom view of a lens barrel of the optical module. It is a side view of the optical component 20 of 1st Embodiment. (A), (b) is a partial cross section figure which shows the variation of the lens-barrel shape and welding position of 1st Embodiment. It is sectional drawing of the optical module of a comparative example. (A), (b), (c) and (d) is sectional drawing, the top view, the side view, and the bottom view of the optical module of 2nd Embodiment. (A), (b) and (c) are sectional drawing, the top view, and the side view of the optical module of 3rd Embodiment. (A), (b) and (c) is sectional drawing, the top view, and the side view of the optical module of 4th Embodiment. (A) And (b) is sectional drawing and a partial side view of the optical module of 5th Embodiment, respectively, (c) is the side view and bottom view of the lens-barrel of the optical module of 5th Embodiment, respectively. It is. (A), (b) and (c) are sectional views, top views, and side views of a lens barrel of another form of the optical module of the fifth embodiment.

  An embodiment of the present invention will be described with reference to the drawings.

<< First Embodiment >>
The optical module of the first embodiment will be described with reference to the drawings. 1A, 1B, and 1C are a cross-sectional view, a side view, and a bottom view, respectively, of an optical module according to the first embodiment. 2A, 2B, and 2C are a cross-sectional view, a side view, and a bottom view of a lens barrel of the optical module, respectively. FIG. 3 is a side view of the optical component 20. 4A and 4B are partial cross-sectional views showing variations of the lens barrel shape and the welding position.

  As shown in FIG. 1, the optical module of this embodiment includes a lens barrel 10 and an optical component 20 that is inserted (press-fitted) from the end of the lens barrel 10. At least a part of the side surface of the optical component 20 is in contact with the inner wall of the lens barrel 10, thereby positioning the optical component 20 with respect to the lens barrel 10 in a direction perpendicular to the axial direction (diameter direction).

  In the lens barrel 10, one or more (three in this case) openings 30 are provided at predetermined intervals in the circumferential direction in a region where the side surface of the optical component 20 is in contact with the inner wall of the lens barrel 10. A partial region of the optical component 20 and the lens barrel in contact with the partial region are welded to form a welded portion 40.

  Thus, in this embodiment, the opening 30 is provided in the outer periphery of the lens barrel 10, and the region where the optical component 20 exposed from the opening 30 is in contact with the lens barrel 10 is welded. Thereby, the optical component 20 is exposed from the opening 30, and the position of the optical component 20 in the lens barrel 10 can be confirmed from the outside. Therefore, as shown in FIG. 5 which is a comparative example, welding is performed with a large gap in which the optical component 20 does not reach a predetermined position in the axial direction of the lens barrel 10 due to insufficient insertion (press-fit) of the optical component 20. There is no fear of doing. The position of the optical component 20 in the optical component 20 can be confirmed by visual observation, or an image in the opening 30 can be taken and automatically inspected by image processing.

  Further, since the welded portion 40 can be formed by irradiating a laser beam such as a YAG laser from the outer periphery of the lens barrel 10 through the opening 30 to the position where the optical component 20 and the lens barrel 10 are in contact, the outer periphery of the lens barrel 10 is externally provided. Welding can be performed by irradiating with laser light. Therefore, even when there are a plurality of optical components inserted into the lens barrel 10, any one of the optical components can be welded by accessing from the outer periphery. There is no need to hold it again toward the light source, and man-hours can be reduced.

  Further, as shown in FIG. 1C, even when a plurality (three) of openings 30 are provided along the circumferential direction of the lens barrel 10, the lens barrel 10 into which the optical component 20 is press-fitted is used as the lens barrel. By rotating relative to the laser light source about the 10 axis, it is possible to perform welding by irradiating each of the plurality of openings 30 with laser light. Alternatively, three laser light sources may be prepared, and welding may be performed by simultaneously irradiating laser beams toward the three openings 30. In the case of simultaneous irradiation, the optical component 20 can be prevented from being displaced due to welding distortion.

  Furthermore, the optical component 20 of the present embodiment is a packaged laser diode. Specifically, for example, a laser diode packaged in a metal can is used. Therefore, as shown in FIGS. 1A and 3, the optical component 20 is mounted on the pedestal portion 21 in which the submount substrate is disposed, and on the pedestal portion 21, and the semiconductor light emitting chip is disposed in the interior. The light emitting unit 22 is provided. The pedestal portion 21 has a diameter larger than that of the light emitting portion 22, protrudes in a flange shape from the light emitting portion 22, and an outer peripheral surface 21 a is in contact with the inner wall of the lens barrel 10. The opening 30 is provided at a position where a corner portion where the outer peripheral surface 21a and the upper surface 21b project in a flange shape of the pedestal portion 21 intersect is exposed.

  On the other hand, a step 11 is provided on the inner wall of the barrel 10 at a position corresponding to the corner 21c of the base 21 of the optical component 20 as shown in FIG. The inner peripheral surface 11a of the step 11 on the inner wall of the lens barrel 10 is in contact with the outer peripheral surface 21a of the pedestal portion 21 of the optical component 20, and the lower surface 11b of the step 11 is on the upper surface 21b of the portion of the pedestal portion 21 that protrudes in a flange shape. They are in contact with each other. In other words, in this embodiment, the upper surface 21b of the flange portion of the pedestal portion 21 of the optical component 20 is abutted against the lower surface 11b of the step 11 of the lens barrel 10, thereby positioning the optical component 20 in the axial direction of the lens barrel 10. Is going. At this time, since the opening 30 is provided in the configuration of the present embodiment, whether or not the lower surface 11b of the step 11 of the lens barrel 10 and the upper surface 21b of the pedestal portion 21 of the optical component 20 are abutted through the opening 30. Can be confirmed from the outside. The abutting state here means that the distance between the lower surface 11 b and the upper surface 21 b is a value suitable for forming the welded portion 40. Specifically, the distance between the lower surface 11b and the upper surface 21b is preferably 0 to 20 μm, and particularly preferably around 10 μm.

  In such a configuration, as shown in FIGS. 1A and 2A, the region A of the opening 30 is a through hole through which the pedestal portion 21 is exposed, and the region B of the opening 30 has a depth ( (The radial direction) is a hole having a designed bottom surface 30a. As a result, the upper surface 21b of the peripheral portion of the pedestal portion 21 is partially exposed from the opening 30, so that the "position a" where the upper surface 21b of the pedestal portion 21 and the bottom surface 30a (lens barrel 10) of the opening 30 are in contact with each other. The weld 40 can be formed by fillet welding.

  4A, the region A of the opening 30 is a through hole in which the pedestal portion 21 is exposed, and the region B of the opening 30 is the bottom surface 30a of the opening 30 and the outer peripheral surface of the pedestal portion 21. It is the depth (radial direction) that matches 21a. In this case, the “position b” where the corner portion 21 c of the pedestal portion 21 and the bottom surface 30 a (lens barrel 10) of the opening 30 are in contact can be welded by butt joint welding to form the welded portion 40.

  In the welding shown in FIGS. 1A, 4A, and 4B, the optical axis of the laser beam is not less than 10 degrees and not more than 45 degrees with respect to the joint surface between the lens barrel 10 and the optical component 20. It is desirable that the angle α be set so that the laser beam can be irradiated. By setting to such an angle, the welding range in a joint surface becomes wide, and the strong welding part 40 can be formed.

  In the structures shown in FIGS. 1A and 4A, when the optical module is fixed to another device, the lens barrel 10 is pushed down in the axial direction, and the optical component 20 is pushed up in the axial direction. When it works, the force in the direction of pressing the upper surface 21 b of the flange-shaped pedestal portion 21 of the optical component 20 against the lower surface 11 b of the step 11 of the lens barrel 10 that is in contact acts on the welded portion 40. Since this force is a stress in a direction in which the welded portion 40 is compressed, the welded portion 40 is hardly broken and the optical component 20 can be firmly fixed to the lens barrel 10.

  Further, as shown in FIG. 4B, the “position c” where the lower end of the opening 30 of the lens barrel 10 and the outer peripheral surface 21 a of the pedestal portion 21 of the optical component 20 are in contact is welded by fillet welding to be a welded portion 40. May be formed.

<< Second Embodiment >>
The optical module according to the second embodiment will be described with reference to FIG. 6A, 6B, 6C, and 6D are a cross-sectional view, a top view, a side view, and a bottom view of the optical module of the present embodiment.

  The optical module of the present embodiment is formed in a notch shape in which the opening 30 reaches the end of the lens barrel 10. A portion where the upper surface of the pedestal portion 21 is in contact with the bottom surface of the opening 30 (lens barrel 10) is welded by fillet welding to form a welded portion 40. Other configurations are the same as the configuration of FIG. 1A of the first embodiment.

  Since the opening 30 of the present embodiment has a notch shape, the pressure applied to the optical component 20 when the optical component 20 is press-fitted into the lens barrel 10 is reduced as compared with the configuration of the first embodiment. Therefore, it is particularly suitable for the case where the optical component 20 having a small strength against the pressure at the time of press fitting is used.

  In the configuration of FIG. 6, it is also possible to change the depth of the opening 30 and form the weld 40 by butt joint welding, as shown in FIG.

<< Third Embodiment >>
An optical module according to the third embodiment will be described with reference to FIG. FIGS. 7A, 7B, and 7C are a cross-sectional view, a top view, and a side view of the optical module of the present embodiment.

  The optical module of the present embodiment is formed in a notch shape in which the opening 30 reaches the shoulder 71 provided on the outer peripheral surface of the lens barrel 10. A portion where the upper surface of the pedestal portion 21 is in contact with the bottom surface of the opening 30 (lens barrel 10) is welded by fillet welding to form a welded portion 40. Other configurations are the same as those in FIG. 1A of the first embodiment.

  In the configuration of the present embodiment, as shown in FIG. 4A, the depth of the opening 30 can be changed, and the weld 40 can be formed by butt joint welding, as shown in FIG. Thus, it is also possible to form the weld 40 by fillet welding at the lower end of the opening 30.

<< Fourth Embodiment >>
The optical module of the fourth embodiment will be described with reference to FIG. FIGS. 8A, 8B, and 8C are a cross-sectional view, a top view, and a side view of the optical module of the present embodiment.

  In the optical module of this embodiment, a lens 50 including a lens 51 and a metal frame 52 is inserted into the structure of FIG. 1 of the first embodiment as a second optical component from the upper end of the lens barrel 10 (press-fit). ) Three openings 60 are provided in the circumferential direction at a predetermined angle in the upper part of the lens barrel 10 so as to expose the frame 52 of the lens 50. The lower end of the opening 60 is welded by fillet welding at a position d in contact with the frame 52 to form a welded portion 70.

  In the example of FIG. 8, the opening 60 is provided in a notch shape that reaches the upper end of the lens barrel 10, but it may have a shape similar to the opening 30 instead of the notch shape.

  As described above, even when the plurality of optical components 20 and 50 are mounted on one lens barrel, since the openings 30 and 60 are provided on the outer periphery of the lens barrel 10, the laser light from the outer periphery can be obtained. The welded portions 40 and 70 can be formed on both by irradiation. Therefore, it is not necessary to hold the lens barrel 10 again, and the welding process can be performed in a short time even when the plurality of optical components 20 and 50 are mounted.

<< Fifth Embodiment >>
The optical module of the fifth embodiment will be described with reference to FIG. 9A and 9B are a cross-sectional view and a partial side view of the optical module of the fifth embodiment, respectively, and FIG. 9C is a side view of a lens barrel of the optical module of the fifth embodiment. It is a bottom view.

  In the present embodiment, a protrusion 80 is provided on the inner wall below the opening 30 of the lens barrel 10. Accordingly, when the optical component 20 is press-fitted into the lens barrel 10, the protrusion 80 hits the outer peripheral surface of the optical component 20, so that the protrusion 80 scrapes off the surface of the outer peripheral surface of the optical component 20 as the optical component 20 moves. Therefore, when the outer peripheral surface of the optical component 20 is gold-plated, a region 81 from which the gold plating has been removed is formed.

  At the time of welding, the region 81 where the gold plating of the optical component 20 is scraped off and the inner wall of the lens barrel 10 are welded so that gold does not enter the molten metal by welding. Therefore, a strong weld 90 can be formed.

  The protrusion 80 is designed to have a protrusion height that is greater than the thickness of the gold plating applied to the outer peripheral surface of the optical component 20 and that does not hinder the press-fitting of the optical component 20. For example, when the thickness of the gold plating is 3 μm or less, it is desirable that the protrusion height of the protrusion 80 is about 5 to 20 μm, particularly about 10 μm.

  Further, it is desirable to set the optical axis of the laser beam used for welding so as to make an angle α of 10 degrees or more and 45 degrees or less with respect to the joint surface between the lens barrel 10 and the outer peripheral surface of the optical component 20. In particular, in the present embodiment, the region 81 where the gold plating has been scraped is spaced apart from the inner wall of the lens barrel 10 by the height of the projection 80, so that a laser beam enters the gap. The area to be welded is increased, and the strength of the welded portion 90 is further increased.

  10A, 10B, and 10C are a cross-sectional view, a top view, and a side view of a barrel of another form of the optical module according to the fifth embodiment. The shape of the opening 30 is not limited to the shape shown in FIG. 9, but may be a notch shape extending upward as shown in FIG.

  Further, as shown in FIG. 10, two or more protrusions 80 may be provided for one opening 30, and a welded portion 90 may be formed respectively.

DESCRIPTION OF SYMBOLS 10 ... Lens tube, 20 ... Optical component, 21 ... Base part, 22 ... Light emission part, 30 ... Opening, 40 ... Welding part, 80 ... Protrusion, 81 ... Area where gold plating was scraped off, 90 ... Welding part

Claims (10)

A lens barrel and an optical component inserted from an end of the lens barrel;
At least a part of the side surface of the optical component is in contact with the inner wall of the lens barrel, and the lens barrel has one or more openings in a region where the side surface of the optical component is in contact with the inner wall of the lens barrel. An optical module, wherein a partial region of the optical component exposed from the opening and the lens barrel in contact with the partial region are welded. 2. The optical module according to claim 1, wherein the inner wall closer to the end of the barrel than the opening is in contact with the side of the optical component inserted from the end, and the side of the optical component Protrusions that scrape part of the surface of
An optical module, wherein a partial area shaved by the protrusion on a side surface of the optical component exposed from the opening and an inner wall of the barrel facing the partial area are welded.   3. The optical module according to claim 1, wherein the welding is performed by irradiating a laser beam, and the size of the opening is such that the optical axis of the laser beam is the same as that of the lens barrel. An optical module characterized in that the laser beam is sized so as to be set at an angle of not less than 10 degrees and not more than 45 degrees with respect to a joint surface with the optical component.   4. The optical module according to claim 1, wherein the optical component is a packaged laser diode. 5. 5. The optical module according to claim 1, wherein the optical component includes a pedestal portion in which a submount substrate is disposed, and a semiconductor light emitting chip mounted on the pedestal portion. And a light emitting unit arranged in
The pedestal portion has a larger diameter than the light emitting portion, protrudes in a flange shape from the light emitting portion, and an outer peripheral surface thereof is in contact with an inner wall of the lens barrel,
The optical module is characterized in that the opening is provided at a position where a corner portion where an outer peripheral surface and an upper surface projecting in a flange shape of the base portion intersect is exposed.   The optical module according to claim 5, wherein the pedestal portion is welded to the lens barrel at the corner portion.   6. The optical module according to claim 5, wherein a step is provided on the inner wall of the barrel at a position corresponding to the corner of the pedestal portion of the optical component, and the step on the inner wall of the barrel is The optical module is in contact with the upper surface of the flange-like portion of the pedestal portion.   8. The optical module according to claim 7, wherein the upper surface of the flange-like portion of the pedestal portion is welded to the step of the inner wall of the barrel that is in contact. Optical module.   9. The optical module according to claim 1, wherein the opening has a notch shape reaching an end of the lens barrel. 10.   10. The optical module according to claim 1, wherein there are a plurality of openings, and the plurality of openings are arranged at a predetermined interval in a circumferential direction of the lens barrel. An optical module characterized by that.

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