JP2010278201A - Optical semiconductor element module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an optical axis shift caused by the rotation of a lens holder when welding the lens holder to a struck block. <P>SOLUTION: An optical semiconductor element module includes: a chip supporting stand whose one end surface is made to abut on one end surface of a pair of struck blocks 35, 36 fixed in a case 1; and a lens holder 37 positioned and welded with the end surface made to contact with other end surfaces 35b, 36b of the struck blocks so that coupling efficiency between an optical semiconductor element on a chip supporting stand and the held lens is higher. Shape of the struck blocks 35, 36 and the lens holder 37 are formed so that the end surfaces 35b, 36b of the struck blocks 35, 36 and the end surface of the lens holder 37 contact with each other at a vertical position sandwiching a point P where these end surfaces are welded in a positioning movable range. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical semiconductor element module having an optical semiconductor element fixed in a case, a light guide path extending from the inside of the case to the outside, and a lens for optically coupling the light guide path and the optical semiconductor element, In particular, the present invention relates to a technique for preventing an optical axis shift of a lens caused by welding and fixing a lens holder that holds the lens.

  Among the optical semiconductor element modules, for example, semiconductor laser modules used as light sources for various optical devices are emitted from the semiconductor laser and the semiconductor laser in a case that is miniaturized to a minimum for convenient incorporation into the device. A lens is mounted for condensing the laser light and making it incident on one end side of a light guide formed so as to continue from the inside of the case to the outside.

  In such a semiconductor laser module, not only the degree of balance between the outgoing optical axis of the semiconductor laser and the optical axis of the lens is matched, but also the semiconductor laser is accurately placed at a predetermined distance at which optimum coupling efficiency can be obtained with respect to the lens. There is a need to.

  In order to provide an accurate distance between the semiconductor laser and the lens, a structure shown in FIGS. 9 to 11 is conventionally known.

  That is, a case 1 is formed by a bottomed box-shaped case main body 2 having an upper surface opened and a cover 3 that closes the upper surface, and the substrate 11 is fixed to the bottom surface of the case main body 2.

  A pair of abutting blocks 15, 16 are fixed on the substrate 11 in advance, and the chip support base 13 attaches the end surface 13 a to one end surface 15 a, 16 a of the pair of abutting blocks 15, 16. It is fixed in a contact state. A semiconductor laser 14 (semiconductor light emitting element) is fixed to the upper surface of the chip support 13. The semiconductor laser 14 is fixed so that its optical axis is orthogonal to the extended surface of the end surface 13 a of the chip support 13, and the optical axis of the semiconductor laser 14 passes between the pair of abutting blocks 15 and 16. .

  The other end surfaces 15b and 16b of the butting blocks 15 and 16 are fixed in a state where both ends on the back surface side of the horizontally long rectangular lens holder 17 are in contact with each other. Inside the lens holder 17 is held a lens 20 for converging light from the semiconductor laser 14 and making it incident on one end side of a fiber 25 that forms a continuous light guide path from the inside of the case to the outside.

  The fibers 25 are fixed to the case body 2 by fixing means (not shown), and they are covered with a fiber cover 25 '.

  The lens holder 17 has an optical axis of the lens 20 so that the intensity of light emitted from the other end side outside the case of the fiber 25 is maximized in a state where both ends on the back surface side are in contact with the abutting blocks 15 and 16. Is positioned minutely (on the order of μm) in a plane orthogonal to the upper surface of the abutting block 15 and 16 and fixed by welding with a YAG laser from above. This positioning is performed by a dedicated positioning device (not shown) designed to move the lens holder 17 minutely while monitoring the intensity of the output light of the fiber 25.

  In this way, the abutting block between the chip support 13 and the lens holder 17 is fixed by fixing the chip support 13 and the lens holder 17 so as to sandwich the abutment blocks 15 and 16 fixed on the substrate 11 from the front and rear. 15 and 16 can be kept at a constant distance, and the thickness of the butting blocks 15 and 16 is set to a predetermined length with respect to the lens 20 in advance, so that the chip support 13 and the lens holder The distance to 17 can be matched with the distance at which the optimum coupling efficiency is obtained.

  However, as described above, when welding is performed between the upper surface edge of the lens holder 17 and the upper surface edge of the butting blocks 15 and 16, due to shrinkage of the melted portion at the welding point P, as shown in FIG. The lens holder 17 rotates around the welding point P and the lower side of the lens holder 17 moves away from the abutting blocks 15 and 16, and the optical axis of the semiconductor laser 14 and the lens 20 is deviated from each other. This causes an increase in the distance of the lens 20 and greatly reduces the light output intensity. In particular, the decrease in output intensity due to a change in the distance between the semiconductor laser 14 and the lens 20 is significant.

  As a method for solving this problem, the following Patent Document 1, for example, as shown in FIG. 13, holds the lens 20 at a central portion 17a of a convex lens holder 17 ′ and substantially matches the optical axis of the lens 20. The left and right arm portions 18 and 19 extend at the same height, and a welding point P is defined between the upper surface edge portions of the arm portions 18 and 19 and the upper surface edge portions of the butting blocks 15 and 16 as shown in FIG. In addition, there is a technology that suppresses a change in the distance between the semiconductor laser 14 and the lens 20 due to the rotation by making the center of rotation of the lens holder 17 caused by welding the same height as the optical axis of the lens 20. It is disclosed.

JP-A-5-243688

  However, the technique disclosed in Patent Document 1 is based on the premise that the lens holder 17 is rotated by welding, and the change in the distance between the semiconductor laser 14 and the lens 20 can be suppressed. It cannot be prevented, and it has been difficult to obtain a higher light output.

  An object of the present invention is to solve this problem and to provide an optical semiconductor element module in which an optical axis shift due to rotation of the lens holder does not occur when the lens holder is welded to the abutting block.

In order to achieve the above object, an optical semiconductor element module according to claim 1 of the present invention includes:
Case (1),
An abutment block (35, 36) fixed in the case and having one end face and the other end face parallel to each other;
A chip support (13) fixed in a state where one end surface is in contact with the one end surface of the abutting block;
An optical semiconductor element (14) fixed on the chip support base and in an orientation in which an optical axis is orthogonal to an extended surface of the one end face of the chip support base;
A lens (20) optically coupled to the optical semiconductor element within the case;
The lens has an end face orthogonal to the optical axis of the held lens, and the end face is in contact with the other end face of the abutting block, so that the coupling efficiency of the lens to the optical semiconductor element is high. In an optical semiconductor element module having a lens holder (37) positioned and welded to be
The abutting block and the lens holder are
The other end face of the abutting block and the end face of the lens holder are formed in a shape in contact with each other at a position above and below the point to be welded within the positioning movable range. .

An optical semiconductor element module according to claim 2 of the present invention is the optical semiconductor element module according to claim 1,
The optical semiconductor element is a semiconductor light emitting element;
A fiber (25) for emitting light to the outside of the case;
The light emitted from the semiconductor light emitting element is converged by the lens and incident on the fiber.

  As described above, in the optical semiconductor element module of the present invention, the end surface of the abutting block and the end surface of the lens holder in contact therewith are positioned above and below the point where welding is stopped within the movable range of positioning, that is, at different heights. Even if a force that rotates the lens holder away from the abutting block at a position below the welding point due to the shrinkage of the molten part at the welding point is applied, the welding point Since the lens holder and the abutting block are in contact with each other at a higher position, the rotation is prevented. Therefore, the rotation of the lens holder due to welding as in the conventional case does not occur, the optical axis shift due to this can be prevented, and the high coupling efficiency obtained at the time of positioning can be maintained even after welding. it can.

The figure which looked at the inside of the embodiment of the present invention from the side The figure which looked at the inside of the embodiment of the present invention from the upper surface The perspective view of the principal part of embodiment The perspective view of the principal part which shows the modification of this invention The perspective view of the principal part which shows the modification of this invention The perspective view of the principal part which shows the modification of this invention The perspective view of the principal part which shows the modification of this invention The perspective view of the principal part which shows the modification of this invention View of the inside of a conventional device viewed from the side View of the inside of a conventional device from the top Perspective view of main part of conventional device Diagram showing lens holder rotation caused by welding The perspective view of the principal part of another conventional apparatus The figure which shows rotation of the lens holder which arises by welding with the structure of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 and 2 show a schematic structure inside a semiconductor laser module 30 to which the present invention is applied, and FIG. 3 is an enlarged view of a main part thereof.

  As shown in FIGS. 1 and 2, the semiconductor laser module 30 includes a bottomed box-type case body 2 having an upper surface opened and a cover 3 that closes the upper surface, as described above. The substrate 11 is fixed to the bottom surface of the case body 2.

  A pair of rectangular parallelepiped abutting blocks 35, 36 are fixed on the substrate 11 with a gap L2 in advance, and a chip support base is provided on one end face 35a, 36a of the pair of abutting blocks 35, 36. 13 is fixed with its end face 13a in contact. A semiconductor laser 14 (semiconductor light emitting element) is fixed to the upper surface of the chip support 13. The semiconductor laser 14 is fixed so that its optical axis is orthogonal to the extended surface of the end surface 13 a of the chip support 13, and the optical axis of the semiconductor laser 14 passes between the pair of abutting blocks 35 and 36. . Although not shown, it is assumed that a terminal fixed so as to penetrate the side surface of the case body 2 is electrically connected to the electrical component in the case including the semiconductor laser 14.

  A lens holder 37 is fixed to the end surfaces 35b and 36b opposite to the end surfaces 35a and 36a of the abutting blocks 35 and 36 by welding.

  The lens holder 37 is formed in a symmetrical convex shape, and the light from the semiconductor laser 14 is converged inside the central portion 37a and incident on one end of the fiber 25 forming a continuous light guide path from the inside of the case to the outside. The lens 20 for holding is held.

  Note that, here, an example in which the fiber 25 is used as the light guide path is shown, but a configuration may be adopted in which a glass window for light guide is provided on the side surface of the case 1 and light from the lens 20 is emitted from this window. . Arm portions 38 and 39 having a height lower than that of the central portion 37a extend horizontally from the left and right side portions of the central portion 37a.

  Here, as shown in FIG. 3, the width L1 of the central portion 37a of the lens holder 37 is sufficiently larger than the distance (gap) L2 between the inner ends of the abutting blocks 35 and 36 (an amount exceeding the movable range of positioning). : The same applies hereinafter) It is long and is set sufficiently shorter than the distance L3 between the outer ends of the butting blocks 35 and 36. The design height of the upper surfaces 38a, 39a of the arm portions 38, 39 of the lens holder 37 is set to be sufficiently lower than the upper surfaces 35c, 36c of the butting blocks 35, 36. The designed lens optical axis passes through the center of the gap between the abutting blocks 35 and 36.

  Therefore, the design position is such that both ends of the central portion 37a of the lens holder 37 and the arm portions 38 and 39 are in contact with the end surfaces 35b and 36b of the abutting blocks 35 and 36 with a wide width exceeding the movable range of positioning. While maintaining the contact state, the lens holder 37 is moved minutely (on the order of μm) within the plane orthogonal to the optical axis of the lens 20, and the light emitted from the other end side outside the case of the fiber 25. Positioning is performed so that the strength is maximized, and a predetermined position of a boundary portion between the upper surfaces 38a, 39a of the arm portions 38, 39 and the end surfaces 35b, 36b of the abutting blocks 35, 36 is welded by a YAG laser (not shown). To do.

  As described above, this positioning is performed by a dedicated positioning device (not shown) designed to move the lens holder 37 minutely while monitoring the intensity of the output light of the fiber 25.

  Further, in this case, the YAG laser is moved from the space sandwiched between the surface obtained by extending the end surfaces 35b and 36b of the abutting blocks 35 and 36 and the surface obtained by extending the upper surfaces 38a and 39a of the arm portions 38 and 39 to the boundary portion. It will be irradiated diagonally.

  As described above, the abutting blocks 35 and 36 and the lens holder 37 sandwich the welding point P along the upper and lower positions (the direction perpendicular to the bottom surface of the case body 2) between the welding points P within the positioning movable range. (Height position).

  Therefore, even if the force that rotates the lens holder 37 in the direction away from the abutting blocks 35 and 36 at a position below the welding point P due to the shrinkage of the melted portion at the welding point P, the welding point P Since the lens holder 37 and the butting blocks 35 and 36 are in contact with each other at the upper position (that is, the height positions of both ends of the central portion 37a of the lens holder 37), the rotation is prevented.

  For this reason, the rotation of the lens holder 37 due to welding as in the prior art does not occur in principle, and the optical axis shift due to this can be prevented in advance, and the high coupling efficiency obtained at the time of positioning can be reduced after welding. Can also be maintained.

  In the above embodiment, both ends of the central portion 37a of the convex lens holder 37 and the arm portions 38 and 39 are in contact with the end surfaces 35b and 36b of the abutting blocks 35 and 36, and the upper surfaces of the arm portions 38 and 39 are bumped. By setting a predetermined position of the boundary between the end faces 35b and 36b of the contact blocks 35 and 36 as a welding point, both are in contact with each other at positions above and below the welding point P. Any shape can be used as long as the shapes are in contact with each other at the upper and lower positions.

  For example, as shown in FIG. 4, using a symmetrical trapezoidal lens holder 37 ′, the abutting block 35, in the middle height range of the inclined surfaces 38 a ′ and 39 a ′ of the arm portions 38 ′ and 39 ′, By welding a predetermined position at the boundary between the end faces 35b and 36b of the 36 with a YAG laser, it is possible to realize a state where they are in contact with each other at the upper and lower positions of the welding point P, and the rotation of the lens holder 37 'due to welding can be prevented. .

  Further, in the above example, a step or an inclination is provided on the upper surface of the lens holder. However, as shown in FIG. 5, the upper surface of the lens holder 37 ″ is flat over the entire length, and the abutting blocks 35 ′, 36 ′. High step portions 35c ', 36c' and low step portions 35d ', 36d' are formed on the upper surface of the lens, and a welding point is formed at a boundary portion where the low step portions 35d ', 36d' and both ends of the lens holder 37 'are in contact with each other. P may be provided.

  Further, as shown in FIG. 6, inclined surfaces 35e 'and 36e' are formed on the upper surface side of the abutting blocks 35 'and 36', the inclined surfaces 35e 'and 36e and both ends of the lens holder 37 "on the back surface side. A welding point P may be provided at a boundary portion where the two contact with each other, and the shapes of the abutting block and the lens holder may be variously modified, and may be an asymmetric shape instead of a symmetric shape.

  Moreover, in the above-described example, it is necessary to irradiate the YAG laser obliquely toward the boundary portion of the surfaces orthogonal to each other on the upper side of the portion where the abutting block and the lens holder are in contact with each other. Although it is necessary to change the YAG welding direction of the manufacturing system, as shown in FIG. 7, the convex lens block 37 and the abutting blocks 35 ′ and 36 having steps substantially equal to the steps at both ends of the lens block 37. ′ And the position where the stepped portions overlap so that they almost coincide with each other is designed to be finely positioned, and the YAG laser is applied from the position directly above the boundary between the lower stepped portions of the stepped portion. Irradiation is possible, and there is no need to change the YAG welding direction of the conventional manufacturing system.

  Further, as shown in FIG. 8, a lens block 37 ′ having inclined portions on both sides and abutting blocks 35 ′ and 36 ′ having inclined portions having angles substantially equal to the inclinations on both sides of the lens block 37 are used. If minute positioning is performed using the overlapping position so that the inclined portions coincide with each other, the YAG laser can be irradiated from the position directly above the boundary portion at the intermediate height of the inclined portion. There is no need to change the YAG welding direction of the manufacturing system.

  In the above-described example, a pair of left and right abutting blocks separated from each other is used. However, even if the abutting blocks are formed in a substantially concave shape by connecting the lower portions of each pair of abutting blocks. Well, it doesn't have to be two separate parts.

  In the above embodiment, the structure of the semiconductor laser module is simply shown. In practice, however, an electronic cooling element (Peltier element) for cooling the light emitting element is fixed under the substrate 11 or the lens 20. An optical isolator is inserted before or after the above, or a monitor light receiver for receiving light from the end surface opposite to the lens side of the semiconductor laser 14 is provided on the chip support base 13, The above-described embodiment can be applied to a product.

  Moreover, although the said embodiment was an example of the semiconductor laser module, instead of the semiconductor laser 14, the semiconductor light receiving element (a photodiode, an avalanche photodiode, etc.) is supported on the chip | tip support stand 13, fiber etc. from the case exterior The present invention can be similarly applied to a module in which the light guided by the light guide path is converged by the lens 20 and enters the semiconductor light receiving element.

  DESCRIPTION OF SYMBOLS 1 ... Case, 2 ... Case main body, 3 ... Cover, 11 ... Board | substrate, 13 ... Chip support, 14 ... Semiconductor laser, 20 ... Lens, 25 ... Fiber, 35, 36 ... Thing Contact block, 37 …… Lens holder

Claims (2)

Case (1),
An abutment block (35, 36) fixed in the case and having one end face and the other end face parallel to each other;
A chip support (13) fixed in a state where one end surface is in contact with the one end surface of the abutting block;
An optical semiconductor element (14) fixed on the chip support base and in an orientation in which an optical axis is orthogonal to an extended surface of the one end face of the chip support base;
A lens (20) optically coupled to the optical semiconductor element within the case;
The lens has an end face orthogonal to the optical axis of the held lens, and the end face is in contact with the other end face of the abutting block, so that the coupling efficiency of the lens to the optical semiconductor element is high. In an optical semiconductor element module having a lens holder (37) positioned and welded to be
The abutting block and the lens holder are
The other end face of the abutting block and the end face of the lens holder are formed in a shape in contact with each other at a position above and below the point to be welded within the positioning movable range. Optical semiconductor element module. The optical semiconductor element is a semiconductor light emitting element;
A fiber (25) for emitting light to the outside of the case;
The optical semiconductor element module according to claim 1, wherein the light emitted from the semiconductor light emitting element is converged by the lens and incident on the fiber.

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