JP2014002284A - Lens array and optical module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens array with a support body which facilitates positioning adjustment when mounting on an optical module and provides highly accurate optical performance.SOLUTION: A lens array 1 with a support body includes: a lens array 3 having an incident face, an exit face, and an outer periphery; and a support body 4 which holds the outer periphery. The outer periphery comprises a top face 3i, bottom face 3g opposite the top face 3i, and side faces 3h, 3j that connect the top face 3i and the bottom face 3g. The bottom face 3g is exposed from the support body 4.

Description

  The present invention relates to a lens array used for an optical module or the like, and more particularly to a lens array held by a holding body.

  In recent years, as optical communication networks have been increased in speed and capacity, there has been an increasing demand for simplification and miniaturization of optical modules. In addition, with this increase in speed and capacity, wavelength division multiplex communication using a plurality of different wavelengths of light has become widespread, and a lens array including a plurality of lenses that receive a plurality of different wavelengths of light for each wavelength. Used in optical modules.

  With the miniaturization of the optical module, the distance between the lens array and the optical module side wall is narrowed. Therefore, there is no room for an arm or the like that sandwiches and conveys the side surface of the lens array to enter the gap between the lens array and the side wall of the optical module, making it difficult to incorporate the lens array into the optical module.

  Therefore, in the optical module 500 disclosed in Patent Document 1, as shown in FIG. 12, the lens 503 is held by a metal holding body (outer frame) 504, and the holding body 504 has an arm (jig) or the like. A convex portion 506 is formed that protrudes upward (Z2) to be grasped. A fixed guide (pedestal) 505 is fixed to the bottom of the housing (package) 507 of the optical module 500 by welding.

  Then, an arm or the like inserts the holding body 504 into the fixed guide 505 while sandwiching the convex portion 506. Next, the holding body 504 is slid up and down (Z direction) and front and rear (Y direction) by an arm or the like, and is positioned and adjusted in the (vertical) direction perpendicular to the optical axis and the optical axis (front and rear) direction. The holding body 504 is fixed to the fixed guide 505 by welding.

  In the optical module 600 disclosed in Patent Document 2, as shown in FIG. 13, a lens 603 having a rectangular (quadrangle) outer shape is arranged such that its optical center coincides with the optical axis of the laser element 608 serving as a light source. , And is fixed to the bottom of the housing (carrier) 607 by an adhesive 604 such as an adhesive.

  Further, an ultraviolet curable adhesive may be used as the fixing agent 604. In some cases, the outer portion of the lens 603 is made of metal, and solder is used as the fixing agent 604.

Japanese Patent Laid-Open No. 2003-12487 JP 2010-60897 A

  As shown in FIG. 13, the lens 603 disclosed in Patent Document 2 includes a fixing agent 604 that is an ultraviolet curable adhesive, or a fixing agent 604 that is a metal (not shown) and solder. Fixed to the bottom.

  When the fixing agent 604 is an ultraviolet curable adhesive, there is a problem in that the optical axis alignment accuracy in the vertical direction is hindered due to a dimensional error in the vertical (Z) direction of the adhesive. Further, when the temperature in the optical module 600 is increased, the resin adhesive such as the ultraviolet curable resin is softened. Therefore, there is a problem that the lens 603 is displaced and the optical coupling efficiency between the lens 603 and the laser element 608 is lowered. In particular, when the lens 603 is installed in the vicinity of the laser element 608 that becomes high temperature during use, this problem is remarkable.

  When the lens 603 is fixed to the bottom of the housing 607 via a metal (not shown) and a bonding agent 604, which is a solder, the lens 603 is moved in the vertical direction due to dimensional errors in the vertical direction of the metal and the solder. There was a problem that the optical axis alignment accuracy was hindered.

  In Patent Document 1, the fixed guide 505 and the housing 507, and the holding body 504 and the fixed guide 505 are fixed by welding, and the holding body 504 is slid up and down to adjust the position in the direction perpendicular to the optical axis. The problem in Patent Document 2 described above has been solved.

  However, in Patent Document 1, when the holding body 504 is brought into contact with the bottom plate portion 505a of the fixed guide 505 and the lens 503 is fixed to the bottom portion of the housing 507, the vertical dimension variation of the bottom plate portion 505a and the holding body 504 is changed. For this reason, the optical axis of the lens 503 is shifted in the vertical direction from the optical axes of the optical fiber 502 and the optical element 508.

  Therefore, it is necessary to insert the holding body 504 into the fixed guide 505, slide the holding body 504 up and down, and adjust the positioning in the direction perpendicular to the optical axis. Therefore, the problem that the positioning adjustment at the time of incorporating the lens 503 into the optical module 500 becomes complicated and the optical axis alignment accuracy in the vertical direction is hindered.

  An object of the present invention is to provide such a lens array with a holder, which has been made in view of such a problem, is simple in positioning adjustment when assembled in an optical module, and can obtain high-precision optical performance. It is.

  The lens array with a holding body of the present invention is a lens array with a holding body including a lens array having an incident surface, an exit surface, and an outer peripheral surface, and a holding body for holding the outer peripheral surface, and the outer peripheral surface is And an upper surface, a bottom surface opposite to the upper surface, and a side surface connected to the upper surface and the bottom surface, wherein the bottom surface is exposed from the holding body. .

  A lens array with a holder can be manufactured by fixing a lens array manufactured by press molding using a metal mold to a holder obtained by cutting a metal material. In addition, the lens array with the holding body can be integrally formed by an existing technique in which a holding body obtained by cutting a metal material and a glass material or a resin material softened by heating are press-molded using a mold. The holding body is formed so as to expose the bottom surface of the outer peripheral surface of the lens array. Therefore, when the lens array is press-molded using a mold, the highly accurate surface of the mold is transferred to the exposed bottom surface of the lens array with the holding body.

  In addition, since the mold has high dimensional accuracy, the lens array with the holding body can be manufactured with high dimensional accuracy.

  As described above, the lens array with the holding body is manufactured with a high dimensional accuracy and includes a high-precision bottom surface exposed from the holding body. Therefore, the position of the optical axis in the vertical direction is determined with high accuracy by bringing the exposed bottom surface of the lens array with the holding body into contact with the surface of the housing. Therefore, the positioning adjustment at the time of incorporation into the optical module is simple. In addition, since the error associated with the optical axis alignment in the vertical direction is small, highly accurate optical performance can be obtained.

  Therefore, according to the present invention, since the holding body is formed so as to expose the bottom surface of the lens array, the positioning adjustment at the time of incorporation into the optical module is simple, and the holding that provides high-precision optical performance can be obtained. It is possible to provide a lens array with a body.

  The lens array has a rectangular outer shape, and the outer peripheral surface of the lens array is composed of the upper surface, the bottom surface, and a pair of side surfaces connected to the upper surface and the bottom surface, and the holding body is supported on the upper surface. And a pair of side surface support portions connected to the upper surface support portion, and the holding body holds the upper surface and the pair of side surfaces of the lens array so as to surround the pair of side surface support portions of the holding body. It is preferable that the end portion does not protrude from the bottom surface of the lens array.

  In such an embodiment, the holding body holds the lens array so as to surround the upper surface and the pair of side surfaces, so that the holding body can firmly hold the lens array. Further, the bottom surface exposed from the holding body can be brought into contact with the surface of the housing without being obstructed by the holding body. Since the bottom surface is formed in a flat surface, the surface of the housing with which the bottom surface is brought into contact may be formed in a flat surface, which is simpler.

  The optical module of the present invention is an optical module in which a lens array with a holding body is housed in a housing, wherein the housing is a hollow space, and the bottom surface of the lens array exposed from the holding body is the housing. It is preferable that the holding body is fixed to the housing so as to be housed and abutted inside. With such an aspect, the optical axis alignment accuracy in the vertical direction is improved, so that a more accurate optical performance can be obtained.

  Preferably, a laser diode is housed in the housing, and the lens array with the holding body is fixed in the housing at a position where light from the laser diode is received. With such an aspect, the light emitted from the laser diode can be optically coupled to an optical fiber or the like with high accuracy.

  According to the present invention, since the holding body is formed so as to expose the bottom surface of the lens array, the positioning adjustment at the time of incorporation into the optical module is simple, and the holding body with high-precision optical performance is obtained. It is possible to provide a lens array.

It is a perspective view of the lens array with a holding body in a 1st embodiment. It is a front view of the lens array with a holding body in the first embodiment. It is sectional drawing cut | disconnected along the AA line shown in FIG. 2, and seeing from an arrow direction. It is a perspective view of the fixed guide in a 1st embodiment. It is a perspective view seen from the outgoing radiation side where the lens array with a holder in a 1st embodiment is fixed to a fixed guide. It is a perspective view seen from the entrance plane side where the lens array with a holder in a 1st embodiment is fixed to a fixed guide. It is a perspective view by which the lens array with a holding body in the first embodiment is fixed to the housing of the optical module by a fixing guide. It is a top view of the upper metal mold | die and lower metal mold | die of a press apparatus. It is a figure explaining the manufacturing method of the lens array with a holder in a 1st embodiment. It is a perspective view of the fixed guide in 2nd Embodiment. It is a perspective view seen from the outgoing side where the lens array with a holder in a 2nd embodiment is fixed to a fixed guide. 10 is a perspective view of an optical module disclosed in Patent Document 1. FIG. 2 is a schematic cross-sectional view of an optical module disclosed in Patent Document 2.

<First Embodiment>
This embodiment will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a lens array with a holding body in the first embodiment. FIG. 2 shows a front view of the lens array with a holding body in the first embodiment. FIG. 3 shows a cross-sectional view taken along the line AA shown in FIG. FIG. 4 is a perspective view of the fixed guide in the first embodiment. FIGS. 5 and 6 are perspective views of the lens array with the holding body according to the first embodiment fixed to the fixed guide and viewed from the exit surface side or the entrance surface side. FIG. 7 is a perspective view in which the lens array with the holding body in the first embodiment is fixed to the housing of the optical module by a fixing guide. Each drawing is illustrated with dimensions appropriately changed for easy viewing.

  As shown in FIGS. 3, 5, and 6, the lens array 3 of the present embodiment has an exit surface 3e on one of the front and back surfaces, an entrance surface 3f on the other of the front and back surfaces, and an exit surface 3e. The two lens surfaces 3a and 3b are configured to have two lens surfaces 3c and 3d on the incident surface 3f.

  The outer shapes of the exit surface 3e and the entrance surface 3f are rectangular as shown in FIGS. The outer peripheral surface of the lens array 3 is located between the exit surface 3e and the entrance surface 3f, and is connected to both. As shown in FIG. 2, a pair of outer peripheral surfaces are connected to the upper surface 3i in the upper direction (Z2 direction), the bottom surface 3g in the lower side (Z1 direction) opposite to the upper surface 3i, and the upper surface 3i and the bottom surface 3g. Side surfaces 3h and 3j. The outer peripheral surfaces 3g, 3h, 3i, and 3j are formed to be parallel to the optical axes 3m and 3n (shown in FIG. 1) of the lens array 3.

  As shown in FIG. 2, the metal holding body 4 has an upper surface support portion 4a on the upper side (Z2 direction) and a pair of side surface support portions 4b and 4c connected to the upper surface support portion 4a. Yes. The holding body 4 holds the lens array 3 so as to surround the upper surface 3i and the pair of side surfaces 3h, 3j. At that time, the end portions of the pair of side surface support portions 4 b and 4 c of the holding body 4 do not protrude from the bottom surface 3 g of the lens array 3. That is, the holding body 4 holds the side surfaces 3h, 3j so as to surround the side surfaces 3h, 3j adjacent to the bottom surface 3g except for a portion adjacent to the bottom surface 3g.

  Thus, since the holding body 4 is formed so as to cover the three upper surfaces 3i, the side surface 3h, and the side surface 3j of the outer peripheral surface of the lens array 3, the holding body 4 holds the lens array 3 firmly. be able to.

  According to the present embodiment, of the side surfaces 3h and 3j adjacent to the bottom surface 3g, the portion adjacent to the bottom surface 3g is exposed from the holding body 4. However, the present invention is not limited to this. All of the side surfaces 3h and 3j adjacent to the bottom surface 3g can be covered with the holding body 4.

  According to the present embodiment, the four upper surfaces 3i, the bottom surface 3g, the side surfaces 3h, and 3j are formed in a flat plane. However, the present invention is not limited to this, and may be a curved surface.

  In the present embodiment, the lens surfaces 3a, 3b, 3c, and 3d are provided as optical function surfaces. However, other optical function surfaces are possible, for example, a diffraction grating surface is also possible. Further, four lens surfaces are provided as the optical function surfaces, such as the lens surfaces 3a, 3b, 3c, and 3d, but either of them may not be an optical function surface, for example, a flat surface. Is also possible. In addition, although two lens surfaces are provided on each of the front and back surfaces, two or more lens surfaces can be provided.

  As shown in FIG. 2, the holding body 4 is formed with a convex portion 6 that protrudes upward (Z2 direction) from the upper surface 3 i side of the lens array 3. The lens array 1 with the holding body is configured by integrally forming the holding body 4 having the convex portions 6 and the lens array 3. Therefore, the conveyance arm or the like can sandwich the convex portion 6 and incorporate the lens array 1 with the holding body into a housing such as an optical system or an optical module.

  In the present embodiment, as shown in FIG. 7, the optical module 10 includes a housing 7 having a hollow space, and a pedestal 7 a is provided on the rear side (Y2 direction) in the housing 7. Then, two laser diodes 8a and 8b are provided on the pedestal 7a so that the emitting part is directed to the front (Y1 direction) side.

  A fixed guide 5 is fixed to the bottom of the housing 7 located on the front (Y1 direction) side in the housing 7 by welding such as laser irradiation. Two welding points 9b and 9b are illustrated as the welding marks.

  The lens array 1 with the holding body is fixed to the fixed guide 5. Two lights on the front (Y1 direction) side of the lens array 1 with the holder so that the end surfaces of the two optical fibers 2a and 2b face the two lens surfaces 3a and 3b of the lens array 1 with the holder, respectively. Fibers 2a and 2b are provided. A through hole is provided in the side wall of the housing 7 between the two lens surfaces 3a and 3b and the end surfaces of the two optical fibers 2a and 2b.

  As shown in FIG. 4, the fixed guide 5 has a bottom plate portion 5 a provided horizontally (parallel to the XY plane) at its bottom portion, and is a two-sided holding body that is erected from both sides of the bottom plate portion 5 a. It has a support wall 5b.

  Then, as shown in FIGS. 5 and 6, the lens array 1 with the holding body is inserted between the two holding body support walls 5 b, and the exposed bottom surface 3 g of the lens array 1 with the holding body is used as the bottom plate of the fixed guide 5. Positioning adjustment for optical axis adjustment is performed by moving the lens array 1 with the holding body in the front-rear (Y) direction in contact with the portion 5a.

  As shown in FIG. 2, the holding body 4 does not cover a portion adjacent to the bottom surface 3g among the side surfaces 3h and 3j adjacent to the bottom surface 3g. Therefore, the exposed bottom surface 3g can be brought into contact with the bottom plate portion 5a of the fixed guide 5 without being obstructed by the holding body 4, as shown in FIGS. Even when the holding body 4 covers all of the side surfaces 3h and 3j adjacent to the bottom surface 3g, the end portions of the pair of side surface support portions 4b and 4c of the holding body 4 protrude downward (Z1 direction) from the bottom surface 3g. If not, the exposed bottom surface 3 g can be brought into contact with the bottom plate portion 5 a of the fixed guide 5.

  At this time, as shown in FIGS. 5 and 6, the two holding body support walls 5 b included in the fixed guide 5 are configured so that the lens array 1 with the holding body can be freely moved back and forth. After the positioning adjustment, the lens array 1 with the holding body is fixed to the fixed guide 5 by welding the holding body 4 and the holding body support wall 5b by welding such as laser irradiation. As this welding mark, two welding points 9a and 9a are illustrated.

  According to the present embodiment, since the exposed bottom surface 3g of the lens array 1 with the holding body is formed as a flat surface, the top surface (Z2 direction) of the bottom plate portion 5a of the fixed guide 5 that contacts the exposed bottom surface 3g. The plane) may also be a plane. Therefore, the processing of the fixed guide 5 is simpler. Further, the exposed bottom surface 3g and the bottom plate portion 5a can be formed with high accuracy, and thus are excellent in optical performance.

  According to the present embodiment, the fixed guide 5 is preferably formed from, for example, Kovar, which is an alloy in which nickel and cobalt are blended with iron, but is not limited to Kovar. It can also be formed from stainless steel or the like.

  In this way, in the optical module 10, the two lights emitted from the two laser diodes 8 a and 8 b are optically and accurately applied to the end faces of the optical fibers 2 a and 2 b by the lens array 1 with the holding body. Combined.

  According to the present embodiment, two laser diodes and two optical fibers are provided, but the present invention is not limited to this, and two or more laser diodes and optical fibers can be provided.

  Miniaturization of an optical module used for optical communication is required, and the miniaturization of the housing has been achieved. Therefore, as shown in FIG. 7, the distance between the side wall of the housing 7 into which the lens array 3 is incorporated and the lens array 3 is narrowed. However, it is possible to cope with downsizing by using the lens array 1 with the holding body having the convex portions 6 projecting upward (Z2 direction).

  That is, when the lens array 1 with the holding body is inserted into the housing 7, since the convex portion 6 protrudes upward, the transfer arm or the like that sandwiches the convex portion 6 has the side wall of the housing 7 and the lens array 3. Never get into the gap. Therefore, even if the housing 7 such as the optical module 10 is downsized, the arm or the like can hold the convex portion 6 to convey the lens array 1 with the holding body and incorporate the lens array 3 into the optical module 10. is there. Further, the arm or the like can adjust the positioning by holding the convex portion 6 and moving the lens array 1 with the holder back and forth within the fixed guide 5.

  Therefore, even if the housing 7 such as the optical module 10 is downsized, it is not difficult to incorporate the lens array 3 into the housing 7. Suitable for.

  As shown in FIGS. 5 and 6, the lens array 1 with the holding body is fixed to the fixed guide 5 by the holding body 4. Therefore, it is not necessary for the lens array with a holder 1 to fix the exposed bottom surface 3g to the bottom plate portion 5a of the fixing guide 5 with an adhesive or the like. Accordingly, the optical axis alignment accuracy in the vertical direction is not hindered due to the dimensional error in the vertical (Z) direction of the adhesive or the like, so that highly accurate optical performance can be obtained.

  Further, as shown in FIG. 7, when the lens array 1 with the holder is fixed in the housing 7 such as the optical module 10, the holder 4 is made of metal, so that the holder 4 is melted by laser irradiation or the like. It can be fixed to the fixed guide 5 installed in the housing 7 by welding. Therefore, even if the temperature in the housing 7 is increased by the laser diodes 8a, 8b, etc., the welding point 9a does not soften, so that the lens array 1 with the holding body does not shift. Therefore, by using the lens array 1 with the holder, the optical module 10 and the like can stably maintain high-precision optical performance.

  A method for manufacturing the lens array 1 with the holding body will be described with reference to FIGS. FIG. 8 is a plan view of the upper die and the lower die of the press device. FIG. 9 is a diagram for explaining a method of manufacturing a lens array with a holding body in the first embodiment.

  In order to manufacture the lens array 1 with the holding body, the press device 40 is prepared in the process shown in FIG. The press device 40 includes an upper mold 41, a lower mold 42, a body mold 43, and a heater 44.

  As shown in FIG. 8, the upper mold 41 has lens-shaped surfaces 41a and 41b corresponding to the lens surfaces 3a and 3b (shown in FIG. 5). The lower mold 42 has lens-shaped surfaces 42c and 42d corresponding to the lens surfaces 3c and 3d (shown in FIG. 6), a holding body-shaped surface 42e corresponding to the holding body 4 (shown in FIGS. 5 and 6), and a holding The lens array side surface shape surface 42f corresponding to the bottom surface 3g (shown in FIGS. 5 and 6) of the lens array exposed from the body 4 is provided.

  Next, in the step shown in FIG. 9B, the lens material 45 and the holding body 4 are inserted from the opening and placed on the lower mold 42. Then, the lens material 45 is heated above the softening point by the heater 44. In the present embodiment, the lens material 45 is a glass material, but is not limited to a glass material, and a resin material or the like is also possible.

  Next, in the step shown in FIG. 9C, the lens material 45 is pressed from above and below by the upper mold 41 and the lower mold 42. At that time, the mold shapes of the upper mold 41 and the lower mold 42 are transferred to the lens material 45 in a state where the holding body 4 is pressed against the holding body-shaped surface 42e by the softened lens material 45, and the holding body The attached lens array 1 is formed.

  Next, in the step shown in FIG. 9D, the heater 44 is turned off and cooled to a predetermined temperature. Then, the upper mold 41 and the lower mold 42 are pulled out from the barrel mold 43, and the lens array 1 with the holding body is released from the upper mold 41 and the lower mold 42. As described above, the lens array 1 with the holding body is integrally manufactured by press molding the lens array 3 and the holding body 4.

  The materials of the holding body 4 and the lens material 45 are selected so that the thermal expansion coefficient of the holding body 4 is larger than the thermal expansion coefficient of the lens material 45. The lens array 3 is compressed and firmly fixed to the holding body 4 by being selected as described above and returned to room temperature from a temperature equal to or higher than the softening point of the lens material 45.

  As the holding body 4 and the lens material 45 having such a relationship, as the holding body 4, for example, ferritic stainless steel or the like, and as the lens material 45, for example, L-LAH84, L which is a glass type manufactured by OHARA INC. -BAL42 etc. can be selected.

  In the manufacturing method of the lens array 1 with the holding body in the present embodiment, the lens material 45 is heated to the softening point or higher by the heater 44. The mold shapes of the upper mold 41 and the lower mold 42 are transferred to the lens material 45 while the lens material 45 is softened. Therefore, the mold shapes of the upper mold 41 and the lower mold 42 are transferred to the lens array 3 with high accuracy. Therefore, if the processing accuracy and dimensional accuracy of the upper die 41 and the lower die 42 are increased, the processing accuracy and dimensional accuracy of the lens array 1 with the holding body can be increased, and in particular, the shape and flatness of the lens array side surface 42f. The shape and flatness of the bottom surface 3g (shown in FIG. 6) of the lens array 3 exposed from the holder 4 can be improved by increasing the processing accuracy of the lens and the dimensional accuracy between the lens array side surface shape surface 42f and the lens shape surfaces 42c, 42d. And the dimensional accuracy between the bottom surface 3g of the lens array exposed from the holder 4 and the lens surfaces 3c, 3d (shown in FIG. 6) can be increased.

  In this embodiment, the upper mold 41 and the lower mold 42 with high processing accuracy and dimensional accuracy are used, and the processing accuracy and dimensional accuracy of the lens array 1 with the holding body are processed with high accuracy. In particular, the lower mold 42 has a high accuracy in the shape and flatness of the lens array side surface shape surface 42f and the dimensional accuracy between the lens array side surface shape surface 42f and the lens shape surfaces 42c and 42d. The shape and flatness processing accuracy of the bottom surface 3g (shown in FIG. 6) of the lens array 3 exposed from the holding body 4, and the bottom surface 3g and the lens surfaces 3c and 3d of the lens array 3 exposed from the holding body 4 (FIG. 6). Dimensional accuracy between the two) is formed with high accuracy.

  Therefore, as shown in FIGS. 5 and 6, the bottom surface 3 g having the shape and flatness processed with high accuracy of the lens array 1 with the holding body is brought into contact with the upper surface (Z2 direction) of the bottom plate portion 5 a of the fixed guide 5. Since the dimensional accuracy between the bottom surface 3g of the lens array 3 exposed from the holding body 4 and the lens surfaces 3c, 3d is formed with high accuracy, the optical axes of the lens surfaces 3c, 3d The optical axes of the diodes 8a and 8b and the optical fibers 2a and 2b coincide with the vertical (Z) direction with high accuracy.

  Therefore, in the present embodiment, the optical axis position of the lens array 1 with the holding body is highly accurate in the vertical (Z) direction within the fixed guide 5. Accordingly, the bottom surface 3g of the lens array 3 exposed from the holding body 4 is brought into contact with the bottom plate portion 5a of the fixed guide 5, and the lens array 1 with the holding body is moved back and forth (Y direction) in the fixed guide 5, High-precision optical axis adjustment is possible.

  Therefore, according to this embodiment, positioning adjustment at the time of incorporating the lens array 3 into the optical module 10 or the like can be easily performed. Further, since the optical axis position of the lens array 1 with the holding body is highly accurate in the vertical (Z) direction within the fixed guide 5, the error caused by this adjustment is small. Therefore, according to this embodiment, highly accurate optical performance can be obtained.

<Second Embodiment>
FIG. 10 is a perspective view of the fixed guide in the second embodiment. FIG. 11 is a perspective view of the lens array with the holding body according to the second embodiment as viewed from the exit surface side fixed to the fixed guide.

  The fixed guide 5 in this embodiment does not have a bottom plate part as shown in FIG. Then, as shown in FIG. 11, the lens array 1 with the holder is inserted between the two holder support walls 5b and moved in the front-rear direction (Y direction) to adjust the optical axis. When the optical axis adjustment is completed, the lens array 1 with the holding body is welded to the two holding body support walls 5 b and fixed to the fixed guide 5.

  Although not shown, the fixed guide 5 is fixed to a housing such as an optical module by welding as in the first embodiment.

  According to the present embodiment, since the fixed guide 5 does not have a bottom plate portion, the bottom surface 3g exposed from the holding body 4 of the lens array 1 with the holding body abuts on the bottom surface that is a part of the inner side surface of the housing. Has been. Therefore, this embodiment does not include a vertical dimension error due to the thickness of the bottom plate portion of the fixed guide 5 as compared with the first embodiment. Therefore, according to the present embodiment, the optical axis alignment accuracy in the vertical direction is improved, so that a higher accuracy optical performance can be obtained.

DESCRIPTION OF SYMBOLS 1 Lens array 2a with a support body 2b Optical fiber 3 Lens array 3a, 3b, 3c, 3d Lens surface 3e Output surface 3f Incidence surface 3i Top surface 3g Bottom surface 3h, 3j Side surface 3m, 3n Optical axis 4 Holder 5 Fixed guide 5a Bottom plate Part 5b Holding body support wall 6 Convex part 7 Housing 8a, 8b Laser diode 9a, 9b Welding point 10 Optical module

Claims (4)

A lens array comprising an entrance surface, an exit surface, and an outer peripheral surface;
A holding body that holds the outer peripheral surface, and a lens array with a holding body,
The outer peripheral surface has a top surface, a bottom surface opposite to the top surface, and a side surface connected to the top surface and the bottom surface, and the bottom surface is exposed from the holding body. A lens array with a holding body.   The lens array has a rectangular outer shape, and the outer peripheral surface of the lens array is composed of the upper surface, the bottom surface, and a pair of side surfaces connected to the upper surface and the bottom surface, and the holding body is supported on the upper surface. And a pair of side surface support portions connected to the upper surface support portion, and the holding body holds the upper surface and the pair of side surfaces of the lens array so as to surround the pair of side surface support portions of the holding body. The lens array with a holder according to claim 1, wherein the end portion does not protrude from the bottom surface of the lens array.   The optical module in which the lens array with a holding body according to claim 1 or 2 is housed in a housing, wherein the housing is a hollow space, and the bottom surface of the lens array exposed from the holding body is the An optical module, wherein the holding body is fixed to the housing so as to be housed and abutted in the housing. The laser diode is housed in the housing, and the lens array with the holding body is fixed in the housing at a position for receiving light from the laser diode. Optical module.