JP2008130773A - Integrated optical device, integrated optical device mounting method, and optical element manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an integrated optical device that allows the maximum miniaturization of a housing while preventing the housing and an optical element from contacting with each other. <P>SOLUTION: The integrated optical device 11 includes a light-emitting element 13 and an optical element 14 and is mounted to a housing while being angularly displaced around a predetermined angular-displacement axis 15 extending in a direction vertical to an optical axis of light from the light-emitting element 13. When defining one virtual plane 24, a part 26b close to the second end 21b of the optical element 14 in an optical axis direction and facing the one virtual plane 24 is formed so as to be closer to the angular-displacement axis 15 than a part 26a close to a first end 21a of the optical element 14 and facing the one virtual plane 24. The one virtual plane includes a part 23 farthest from the angular-displacement axis 15 at the first end 21a facing the light-emitting element 13 of the optical element 14 and is parallel to the optical-axis direction of outgoing light from the light-emitting element 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an integrated optical device, a method for mounting the integrated optical device, and a method for manufacturing an optical element.

  In devices such as an optical disk device and a laser printer, a light emitting element such as a semiconductor laser chip is used as a light source. For example, in an optical disk device, a semiconductor laser device in which a semiconductor laser chip and a light receiving element are incorporated in one package is provided in an optical pickup device. As a semiconductor laser device, an integrated optical device in which an optical element such as a hologram element is provided on a light emitting side surface from a semiconductor laser chip is widely used. Further, the optical disk device is desired to be reduced in size and thickness, and accordingly, the optical pickup device and the integrated optical device are also desired to be reduced in size and thickness.

  FIG. 11 is a perspective view of the first conventional integrated optical device 1. In the integrated optical device 1 of the first prior art, the planar shape of the stem 2 is obtained by deleting two opposing arcs that form part of a circle, two opposing arcs, and two opposing strings. (See, for example, Patent Document 1). In such an integrated optical device 1, the substantially elliptical arc portion of the stem 2 is used as a reference portion serving as a reference for determining the position of the light emitting point.

  The integrated optical device 1 includes a substantially oval stem 2 made of metal, a substantially oval cap 3, and an optical element 4 that is a glass plate on which a diffraction grating is formed. Inside the cap 3, a semiconductor laser chip, which is a light source, a monitor photodiode, and a signal reading photodiode are die-bonded and electrically connected to the lead pin 5 by a metal wire. The integrated optical device 1 according to the first prior art is thinner than the case where the stem 2 and the cap 3 are formed in a circular shape, for example, by making the stem 2 and the cap 3 have the substantially oval shape.

  Further, a second conventional integrated optical device has been proposed that realizes downsizing of the integrated optical device and is excellent in the ability to emit heat generated by light emission (see, for example, Patent Document 2). A second conventional integrated semiconductor laser device includes a semiconductor laser chip, a light receiving element substrate, a light receiving element, a circuit board, and an optical element. The light receiving element substrate is mounted on the circuit board by a flip chip method. Multi-layer wiring is formed inside the circuit board, and external connection electrodes are arranged at the end of the lower surface of the circuit board. On the upper surface of the light receiving element substrate, the light receiving element is disposed in the light receiving region facing the opening of the circuit board, and the semiconductor laser chip is disposed inside the light receiving region. On the side facing the upper surface of the light receiving element substrate across the circuit board, the optical element having the hologram region is fixed on the circuit board with an adhesive. As described above, in the second conventional integrated optical device, the light receiving element substrate is protected from the external environment by the sealing resin, the optical element, and the adhesive.

  In the second prior art, it is possible to reduce useless space with respect to the structure in which the wiring by the wire bonding method is used and the light receiving element substrate is protected from the external environment by the frame body and the optical element. In addition, since the light receiving element substrate is not housed in the frame, the circuit board and the optical element can be formed to have a size substantially equal to the size of the light receiving element substrate, and the integrated optical device can be miniaturized. be able to. In addition, by making the opening of the circuit board a space partitioned from the outside, it is possible to prevent deterioration of optical characteristics due to heat generated by light emission, for example, and to provide a highly reliable semiconductor laser device.

JP-A-6-5990 JP 2005-268443 A

  For example, in an optical pickup device, an integrated optical device is fixed to a flexible substrate by soldering, and then inserted into and attached to the housing from an opening formed in the housing by deforming the flexible substrate. In such a mounting method, it is possible to prevent the mounting position of the optical element from deviating compared to the case where the soldering for fixing the integrated optical device to the flexible substrate is performed after the integrated optical device is mounted. However, in such an attachment method, the flexible substrate cannot have a margin in its length. Since the optical pickup device itself moves within the optical disk device, making the flexible substrate longer hinders the movement of the optical pickup device due to its bending. If the flexible substrate is too long, a space for accommodating the flexible substrate is required, and the optical pickup device cannot be miniaturized. Accordingly, the flexible substrate is set to a minimum length for inserting the integrated optical device. For example, the integrated optical device is gripped by an attachment device including a gripping means and an arm, and angular displacement is performed around a predetermined axis. Although it inserts in a housing by rotating, the following problems are caused by the restriction of the flexible substrate.

  FIG. 12 is a sectional view of the housing 6 when the integrated optical device 1 according to the first prior art is attached to the housing 6. In the mounting method of the integrated optical device 1 as described above, the integrated optical device 1 is rotated in the direction of the arrow 8 by deforming the flexible substrate 7 fixed to the housing 6, and integrated in the mounting portion in the housing 6. The optical device 1 is inserted. At this time, if the height h and thickness t of the optical element 4 of the integrated optical device 1 are larger than the size of the opening of the housing 6, the optical element 4 comes into contact with the housing 6 and the integrated optical in the housing 6. In some cases, the device 1 cannot be loaded. The same problem occurs when the second prior art integrated optical device is loaded into the housing.

  The height h of the optical element 4 provided in the integrated optical device 1 is determined according to the optical characteristics required for the optical element 4, and it is not easy to reduce the height h of the optical element 4. Therefore, in order to insert the integrated optical device 1 including such an optical element 4 into the housing 6, the design of the housing 6 must be changed, and the housing 6 can be downsized, and thus the optical pickup device. Miniaturization cannot be realized.

  Although the integrated optical device can be inserted into the housing and attached to the flexible substrate, the flexible substrate can be fixed to the housing. However, soldering work becomes difficult, for example, contact with a hook used for soldering to the housing. Productivity is bad.

  An object of the present invention is to provide an integrated optical device, an integrated optical device mounting method, and an optical element manufacturing method capable of miniaturizing the housing as much as possible while preventing contact between the housing and the optical element. It is to be.

The present invention includes a light emitting element and an optical element provided in the light emitting element so that light emitted from the light emitting element is transmitted, and has a predetermined angle extending in a direction perpendicular to the optical axis direction of the light emitted from the light emitting element. An integrated optical device that is angularly displaced about a displacement axis and is attached to a housing,
Of the first end facing the light emitting element of the optical element, the first end of the optical element in the optical axis direction with respect to a virtual plane that includes the portion farthest from the angular displacement axis and is parallel to the optical axis direction. The portion near the second end opposite to the end and facing the virtual one plane is formed closer to the angular displacement axis than the portion facing the first end and facing the virtual one plane. The integrated optical device is characterized by the above.

In the present invention, the optical element includes a diffractive portion that diffracts incident light,
The traveling direction of the light diffracted by the diffraction unit is a direction parallel to the virtual one plane.

  Further, the invention is characterized in that a cross section of the optical element perpendicular to the virtual plane and the angular displacement axis is stepped.

  In the invention, it is preferable that a cross section of the optical element perpendicular to the virtual plane and the angular displacement axis is trapezoidal.

  Further, the invention is characterized in that a portion of the optical element facing the virtual plane is formed to be convexly curved outward in the radial direction around the angular displacement axis.

The present invention also includes a step of fixing the integrated optical device of the present invention to a flexible substrate;
Fixing the flexible substrate to which the integrated optical device is fixed to the housing;
And a step of attaching the integrated optical device fixed to the flexible substrate to the housing by angular displacement about a predetermined angular displacement axis while the flexible substrate is fixed to the housing. It is an installation method of the apparatus.

Further, the present invention provides a diffraction part forming step of forming a plurality of diffraction parts on a translucent substrate,
A groove forming step for forming a first groove having a predetermined width extending in a first direction between adjacent diffractive portions of the translucent substrate;
A first cutting step of forming a second groove having a width smaller than the width of the first groove, cutting the translucent substrate by penetrating the second groove in one thickness direction of the translucent substrate;
And a second cutting step of cutting between adjacent diffractive portions in a second direction perpendicular to the first direction.

In addition, the present invention, before the groove forming step,
The method includes a mark forming step of forming a first mark for forming the first groove and a second mark for forming the second groove.

In the present invention, the translucent substrate comprises:
It is characterized by including an acrylic resin base material and a dielectric film formed on a part of the surface of the acrylic resin base material.

  According to the present invention, the integrated optical device includes a light emitting element and an optical element, and is angularly displaced about a predetermined angular displacement axis extending in a direction perpendicular to the optical axis of light from the light emitting element and attached to the housing. . In such an integrated optical device, a virtual one plane that includes a portion that is farthest from the angular displacement axis among the first end portion of the optical element facing the light emitting element and is parallel to the optical axis direction is defined. The integrated optical device of the present invention is near the second end opposite to the first end of the optical element in the optical axis direction, and the portion facing the virtual plane is near the first end of the optical element. And it is formed closer to the angular displacement axis than the part facing the virtual plane. Thereby, compared to the case where the portion near the second end portion and facing the virtual one plane is not formed closer to the angular displacement axis than the portion near the first end portion and facing the virtual one plane, The distance between the portion near the second end and facing the virtual plane and the angular displacement axis is shortened. Therefore, when the integrated optical device is angularly displaced, the area through which the optical element passes can be reduced, and the possibility that the second end of the optical element contacts the housing can be reduced. Can be reduced in size.

  According to the invention, the optical element includes a diffractive part that diffracts incident light, and the traveling direction of the light diffracted by the diffractive part is a direction parallel to the virtual plane. Thereby, for example, the return light can be made incident on the light receiving surface of the light receiving element arranged perpendicular to the virtual plane. Further, the housing can be further reduced in size.

  According to the invention, the cross section of the optical element perpendicular to the virtual plane and the angular displacement axis is stepped. By forming the cross section of the optical element in a staircase shape, the portion near the second end of the optical element and facing the virtual one plane is the portion near the first end of the optical element and facing the virtual one plane. Rather, it can be formed closer to the angular displacement axis. As a result, the distance between the portion near the second end and facing the virtual plane and the angular displacement axis is shortened, and the region through which the optical element passes when the integrated optical device is angularly displaced is reduced. Therefore, the possibility that the second end portion of the optical element comes into contact with the housing is reduced, and the housing can be miniaturized as much as possible. Further, the step of making the cross section of the optical element a stepped shape can be performed in the same process as the dicing operation of cutting out the optical element, and a reduction in productivity of the optical element is prevented.

  According to the invention, the cross section of the optical element perpendicular to the virtual plane and the angular displacement axis is trapezoidal. The cross section of the optical element has a trapezoidal shape in which the size of the lower base on the first end side is larger than the size of the upper base on the second end side. The portion facing one plane can be formed closer to the first end of the optical element and closer to the angular displacement axis than the portion facing the virtual one plane. Even if the optical element has such a shape, the distance between the portion near the second end and facing the virtual plane and the angular displacement axis is shortened, and the integrated optical device is angularly displaced. Sometimes the area through which the optical element passes can be reduced. As a result, the possibility that the second end of the optical element contacts the housing can be reduced, so that the housing can be made as small as possible. In addition, since there is no edge portion such as a staircase portion in the cross section, it is possible to minimize the influence of the light reflected at the edge portion being incident as stray light. Further, since there is no edge portion in the cross section, the antireflection film can be formed also in the cross section, and the influence of stray light can be more reliably suppressed.

  According to the invention, the portion of the optical element that faces the virtual plane is curved so as to protrude outward in the radial direction around the angular displacement axis. When the portion of the optical element facing the virtual plane is formed to be convexly convex outward in the radial direction around the angular displacement axis, the optical element is optically compared to the case where the optical element is concavely formed. The portion of the element through which light is transmitted is not reduced, and there is no possibility of changing the optical characteristics of the optical element. In addition, since there is no edge portion such as a staircase portion in the cross section, it is possible to minimize the influence of the light reflected at the edge portion being incident as stray light. Further, since there is no edge portion in the cross section, the antireflection film can be formed also in the cross section, and the influence of stray light can be more reliably suppressed.

  According to the invention, the integrated optical device having the above-described effect is attached to the housing by the integrated optical device fixing step, the substrate fixing step, and the attaching step. In the integrated optical device fixing step, the integrated optical device having the above effect is fixed to the flexible substrate. In the substrate fixing step, the flexible substrate on which the integrated optical device is fixed is fixed to the housing. In the mounting step, in a state where the flexible substrate is fixed to the housing, the integrated optical device fixed to the flexible substrate is angularly displaced about a predetermined angular displacement axis and attached to the housing. As described above, when the integrated optical device is fixed to the flexible substrate and the flexible substrate is fixed to the housing, and then the integrated optical device is attached to the housing, for example, the heat of soldering when the integrated optical device is attached to the flexible substrate. Therefore, the adjustment position of the optical element with respect to the light emitting element can be prevented from shifting.

  Moreover, according to this invention, an optical element is manufactured by the manufacturing method including a diffraction part formation process, a groove | channel formation process, a 1st cutting process, and a 2nd cutting process. In the diffraction part forming step, a plurality of diffraction parts are formed on the translucent substrate. In the groove forming step, a first groove having a predetermined width extending in the first direction is formed between adjacent diffractive portions of the translucent substrate. In the first cutting step, a second groove having a width smaller than the width of the first groove is formed, the second groove is penetrated in one thickness direction of the translucent substrate, and the translucent substrate is cut. In a 2nd cutting process, between adjacent diffraction parts is cut | disconnected in the 2nd direction orthogonal to a 1st direction. An optical element having a step shape in a cross section perpendicular to the first direction can be manufactured by a manufacturing method including such steps.

  According to the present invention, the mark forming step is performed before the groove forming step. In the mark forming step, a first mark for forming the first groove and a second mark for forming the second groove are formed. By forming the first mark and the second mark as described above, the first groove and the second groove formed in the groove forming step and the first cutting step can be formed at predetermined positions. .

  According to the invention, the translucent substrate is formed including an acrylic resin base material and a dielectric film formed on a part of the surface of the acrylic resin base material. By forming the dielectric film on, for example, the surface on the side where the diffractive portion is formed, the dielectric film functions as an antireflection film, and the light transmittance of the optical element can be improved. In addition, since such a dielectric film is formed on a part of the surface of the acrylic resin base material, even if an acrylic resin that easily absorbs and expands in a high-temperature and high-humidity environment is used as the base material, the absorbed moisture is removed. It becomes easy and the generation of cracks can be prevented. This improves the reliability of the optical characteristics as the optical element.

  FIG. 1 is a perspective view of an integrated semiconductor laser device 11 according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of the integrated semiconductor laser device 11. FIG. 2 is a cross-sectional view of the integrated semiconductor laser device 11 as seen from a direction parallel to an angular displacement axis 15 described later. The integrated semiconductor laser device 11 is an integrated optical device that generally includes a package 12, a semiconductor laser chip 13 that is a light emitting element, and an optical element 14. The integrated semiconductor laser device 11 of the present embodiment is used, for example, in an optical pickup device that constitutes an optical disk device that records information on an optical recording medium or reproduces information recorded on the optical recording medium.

  The integrated semiconductor laser device 11 is angularly displaced in the direction of an arrow 16 around a predetermined angular displacement axis 15 extending in a direction perpendicular to the optical axis direction of light emitted from the semiconductor laser chip 13, for example, a housing of an optical pickup device. Mounted on. The integrated semiconductor laser device 11 includes, for example, a gripping unit that grips the package 12 of the integrated semiconductor laser device 11, an arm that supports the gripping unit, and a drive unit that drives the arm to be angularly displaceable (not shown). Mounted by mounting means. When such an attachment means is used, the predetermined angular displacement axis 15 extending in the direction perpendicular to the optical axis direction of the light coincides with the rotation axis of the arm. Details of the method of mounting the integrated semiconductor laser device 11 will be described later.

  The package 12 accommodates a semiconductor laser chip 13 that is a light emitting element, and is formed of a stem 17 and a cap 18. The stem 17 of the present embodiment is formed of a metal such as copper or aluminum having excellent thermal conductivity, or a resin, and the planar shape thereof is formed by removing two opposed arcuate portions that form part of the circle. It has a substantially oval shape surrounded by the two arcs and two opposing strings extending in the Y direction. On one surface 17 a of the stem 17, a cap 18 formed of a metal such as copper or aluminum, which is excellent in thermal conductivity, or a resin, like the stem 17, is provided. The cap 18 is formed with an optical window 19 through which light emitted from the semiconductor laser chip 13 toward the optical element 14 passes. A heat sink and a light receiving element (not shown) are fixed in a space formed by the stem 17 and the cap 18, and a semiconductor laser chip 13 as a light emitting element is attached to the heat sink by a heat conductive adhesive. The

  The semiconductor laser chip 13 is an optical element that emits light. The semiconductor laser chip 13 emits red laser light having a wavelength of 650 nm, for example, when electric power is supplied through the lead pins 20. The semiconductor laser chip 13 and a light receiving element (not shown) are electrically connected to an external circuit by a lead pin 20 via a wiring board (hereinafter referred to as “flexible board”) such as a flexible printed circuit (FPC). .

  The optical element 14 is provided in the semiconductor laser chip 13 so that light emitted from the semiconductor laser chip 13 can pass therethrough. In the present embodiment, the optical element 14 is provided in contact with the cap 18 of the package 12 in which the semiconductor laser chip 13 is accommodated. The optical element 14 includes a first end 21a facing the semiconductor laser chip 13 and a second end 21b opposite to the first end 21a.

  In the present embodiment, the optical element 14 is a surface formed by the first end portion 21a, and is formed by the incident surface 22a on which the light emitted from the semiconductor laser chip 13 is incident and the second end portion 21b. And a light exit surface 22b from which light incident on the optical element 14 exits. In the present embodiment, the incident surface 22a and the emitting surface 22b of the optical element 14 are parallel to the surface 17a on one side in the thickness direction of the stem 17, and the optical axis direction of the light emitted from the semiconductor laser chip 13 is the optical element 14. It is perpendicular to the entrance surface 22a and the exit surface 22b.

  In the present embodiment, the direction in which the substantially oval stem 17 extends is defined as the Y direction, the optical axis direction perpendicular to the incident surface 22a is defined as the Z direction, and the direction perpendicular to the Y direction and the Z direction is defined as the X direction. Further, of the first end 21a facing the semiconductor laser chip 13 of the optical element 14, a plane that includes the portion 23 that is farthest from the angular displacement axis 15 and that is parallel to the Z direction, which is the optical axis direction, is a virtual plane. 24.

  In the optical element 14 of the present embodiment, diffraction gratings 25a and 25b, which are diffraction portions, are formed on the incident surface 22a and the output surface 22b, respectively. Such diffraction gratings 25 a and 25 b diffract the light so that the traveling direction of the light emitted from the emission surface 22 b is parallel to the virtual plane 24. Thereby, the optical element 14 of the present embodiment can be used as a hologram element used in an optical pickup device, for example. In addition, since the traveling direction of the light diffracted by the diffraction unit is parallel to the virtual plane, the return light is incident on the light receiving surface of the light receiving element arranged perpendicular to the virtual plane 24. Can do. Further, the housing can be further reduced in size.

  The optical element 14 has a virtual one plane 24 parallel to the optical axis direction, and a portion 26a that is close to the second end 21b of the optical element 14 and faces the virtual one plane 24 in the Z direction that is the optical axis direction is It is characterized in that it is formed closer to the angular displacement axis 15 than the portion 26b that faces the one end 21a and faces the virtual plane 24.

  In the optical element 14 of the present embodiment, the cross section perpendicular to the virtual plane 24 and the angular displacement axis 15 has a staircase shape. That is, in the optical element 14 of the present embodiment, the cross section viewed from the Y direction, which is one direction perpendicular to the optical axis direction, has a staircase shape. If the cross section of the optical element 14 is stepped, the portion 26b of the optical element 14 that faces the second end 21b and faces the virtual plane 24 in the Z direction that is the optical axis direction is closer to the first end 21a. In addition, it is formed closer to the angular displacement axis 15 than the portion 26a facing the virtual one plane 24. The integrated semiconductor laser device 11 having the optical element 14 having such a shape can be manufactured, for example, by the following optical element manufacturing method of the present embodiment.

  FIG. 3 is a plan view of the translucent substrate 31 on which a plurality of diffraction gratings 32 are formed. FIG. 4 is an enlarged plan view of the translucent substrate 31 on which the first mark 33 and the second mark 34 are formed. FIG. 5 is a perspective view of the optical element 14 obtained from the translucent substrate 31. 3 and 4 are plan views of the translucent substrate 31 as viewed from the side where the diffraction grating 25b on the exit surface 22b side is formed, and the diffraction grating 32 in FIGS. 3 and 4 is diffracted on the exit surface 22b side. It is a lattice 25b. The diffraction grating 25a on the incident surface 22a side is formed at the same position as the diffraction grating 25b, that is, the diffraction grating 32, on the back side of the paper surface of FIGS. The plurality of diffraction gratings 32 are equally spaced in a first direction (indicated as “y direction” in FIGS. 3 to 5, hereinafter referred to as “first direction y”) that is the vertical direction of the paper surface of FIGS. 3 and 4. Formed side by side and formed side by side in a second direction (shown as “x direction” in FIGS. 3 to 5, hereinafter referred to as “second direction x”) that is the left-right direction of the paper surface of FIGS. Is done. The first direction y and the second direction x correspond to the Y direction and the X direction, respectively, when the integrated semiconductor laser device 11 is provided as the optical element 14.

  In the present embodiment, translucent substrate 31 is an acrylic resin base material 36 having a disc shape and having dielectric film 35 formed thereon. The dielectric film 35 is a film in which, for example, a first film made of a mixed layer of titanium oxide and zirconium oxide having a relatively high refractive index and a second film made of silicon oxide having a relatively low refractive index are stacked. is there. The first film and the second film may be formed one by one, or may be a multilayer of four or more layers in which a plurality of two or more layers are formed. The first film and the second film are formed, for example, with substantially the same thickness, and the dielectric film 35 as a whole is preferably formed with a thickness of 0.4 μm or more and 1.0 μm or less. In such a dielectric film 35, a first film is formed on the surface on which the diffraction grating 25b on the emission surface 22b side is formed by vapor deposition or sputtering, and the surface on which the first film is formed. In addition, it is obtained by forming the second film by vapor deposition or sputtering. When the dielectric film 35 is a multilayer of four or more layers, the first film and the second film are sequentially formed after the second film is formed. By forming such a dielectric film 35, the dielectric film 35 functions as an antireflection film, and the transmittance of light from the diffraction grating 25b can be improved.

  The method for manufacturing an optical element according to the present embodiment includes a diffraction grating forming step, a groove forming step, a first cutting step, and a second cutting step. In the diffraction grating forming step, the diffraction grating 32 as a plurality of diffraction portions is formed on the translucent substrate. Formation of the diffraction grating 32 on the translucent substrate 31 can be performed by a known method. For example, the diffraction grating 32 can be formed by forming a photosensitive material film on the washed translucent substrate 31, developing the pattern of the diffraction grating 32 on the photosensitive material film, and then etching the pattern.

  When forming the diffraction grating 32 as described above, to form the first mark 33 for forming the first groove in the groove forming process described later and the second groove in the first cutting process described later. The second mark 34 is preferably formed together with the diffraction grating 32. The first mark 33 and the second mark 34 may be formed on one surface of the translucent substrate 31.

  As shown in FIG. 4, the first mark 33 includes an end portion 32a of the diffraction grating 32 on one xa side in the second direction x and an end of the first mark 33 on one xa side in the second direction x. It is formed at a position where the distance from the portion 33a is d1. The second mark 34 includes an end portion 33a of the first mark 33 on one xa side in the second direction x and an end portion 34b of the second mark 34 on the other xb side in the second direction x. It is formed at a position where the distance is d2. At this time, the distance between the end 34b of the second mark 34 on the other xb side in the second direction x and the end 32b of the diffraction grating 32 adjacent to the diffraction grating 32 on the other xb side in the second direction x. Becomes d3. A plurality of first marks 33 and second marks 34 are formed side by side in the second direction y.

  Although the distances d1, d2, and d3 are not particularly limited, in the present embodiment, the first mark 33 and the second mark 34 are formed at positions where d1 + d2 = d3. By forming the first mark 33 and the second mark 34 at a position where d1 + d2 = d3, the diffraction grating 32 can be disposed near the center of the incident surface 22a of the optical element 14. Accordingly, for example, even when the dimension of the optical element 14 in the X direction is substantially equal to the dimension of the cap 18 in the X direction, the optical element 14 can be provided at a position where the optical element 14 does not protrude from the cap 18. .

  In the groove forming step, the first groove 37 extending in the first direction y and having a predetermined width is formed between the adjacent diffraction gratings 32 of the translucent substrate 31 in the second direction x. In the groove forming step, the end portion 33a of the first mark 33 on one xa side in the second direction x and the end portion of the first groove 37 on the other xb side in the second direction x are aligned. , A first groove 37 having a width W and a depth D is formed. The width W and depth D of the first groove 37 are determined by the size of the housing to which the integrated semiconductor laser device 11 is attached. A method for forming the first groove 37 is not particularly limited, and examples thereof include a method using etching or a method using a laser.

  Here, the width W of the first groove 37 is determined by the size of the housing to which the integrated semiconductor laser device 11 is attached and the end 33a of the first mark 33 on the one side xa in the second direction x. And a distance d2 (hereinafter referred to as "distance d2 between the first and second marks 33, 34") between the second mark 34 and the end 34b on the other xb side in the second direction x. The dimension is a dimension that is equal to or smaller than the distance d2 between the first and second marks 33 and 34. If the width W of the first groove 37 is equal to or less than half the distance d2 between the first and second marks 33 and 34, the integrated semiconductor laser device 11 can be used even if the width of the first groove 37 is reduced. There is a possibility that the housing and the optical element 14 come into contact with each other during the mounting. Further, when the width W of the first groove 37 becomes larger than the distance d2 between the first and second marks 33, 34, the second mark 34 is scraped off and the cutting position in the first cutting step is determined again. It is necessary to form a mark. Therefore, by setting the width W of the first groove 37 as described above, the contact between the housing and the optical element 14 can be reliably prevented, and the cutting position in the first cutting step is not determined again. After the groove forming step, the first cutting step can be started.

  The depth D of the first groove 37 is determined according to the dimension of the housing to be attached, the dimension of the optical element 14, the width W of the first groove 37, and the like, and is not particularly limited. The depth D of the first groove 37 is determined according to the most virtual rotation center radius attached to the housing, that is, the distance R shown in FIG. The depth D of the first groove 37 is, for example, 0.5H or more when the dimension in the Z direction (hereinafter referred to as “height dimension”) of the optical element 14 that is the thickness dimension of the translucent substrate 31 is H. It is preferably less than 0.0H. If the depth D of the first groove 37 is less than 0.5H, the optical element 14 and the housing may come into contact with each other when the integrated semiconductor laser device 11 is attached, and the housing can be made thin. It may not be possible. If the depth D of the first groove 37 is 1.0H, a step cannot be formed in the optical element, and the dimension in the X direction is smaller than that of the optical element 14 in which the first groove 37 is formed. The optical element is reduced by the width W of one groove 37.

  As described above, the optical element is attached to the package 12 with an adhesive having thermal conductivity. When the dimension of the optical element in the X direction is reduced by the width W of the first groove 37, the contact area between the optical element and the package 12 is reduced, and the fixing strength of the optical element is reduced. This may reduce the reliability of the optical characteristics of the optical element. Therefore, it is impossible to achieve both reduction in size of the housing and reliability of the optical characteristics simply by reducing the size of the optical element.

  In the first cutting step, a second groove having a width smaller than the width of the first groove 37 is formed, and the second groove is penetrated in one thickness direction of the translucent substrate 31 so that the translucent substrate 31 is formed. Disconnect. The translucent substrate 31 in which the first groove 37 is formed is cut in the end portion 33a of the first mark 33 on the one side xa in the second direction x other than the portion in which the first groove 37 is formed. And the portion between the end 34b of the second mark 34 on the other xb side in the second direction x, for example, by etching or cutting with a laser. In the first cutting step, a second groove having a width (d2-W) is formed, and the light-transmitting substrate 31 is passed through the second groove, whereby the light-transmitting substrate 31 is cut. The second groove is formed so that the end on one xa side in the second direction x coincides with the end 34b of the second mark 34 on the other xb side in the second direction x. Such a second groove is formed until the depth matches the height dimension H of the optical element 14, and the translucent substrate 31 is penetrated. Thereby, as shown in FIG. 5, the translucent board | substrate 31 can be cut | disconnected so that the cross section seen from the Y direction may become step shape.

  In the second cutting step, a gap between adjacent diffraction gratings 32 in the first direction y is cut in a second direction x orthogonal to the first direction y. The cutting position in the second cutting step may be determined when the first mark 33 and the second mark 34 are formed. When the translucent substrate 31 is cut in the second direction x indicated by a one-dot chain line 38 in FIG. 4 in the second cutting step, the optical element 14 having a stepped cross section when viewed from the first direction y, that is, the Y direction, is obtained. Obtainable.

  In the optical element 14 manufactured as described above, a step is formed on the end 39a on one side in the X direction of the cross section viewed from the Y direction, and no step is formed on the end 39b on the other side in the X direction. As a result, the time required for producing the steps can be minimized, and productivity can be improved.

  Moreover, since the dielectric film 35 is formed on the emission surface 22b, the optical element 14 manufactured as described above can prevent light reflected by the step portion from entering from the emission surface 22b. That is, the dielectric film 35 functions as an antireflection film. As a result, it is more reliably prevented that the reliability of the optical element 14 relating to the optical characteristics is lowered.

  As described above, the cross section viewed from the Y direction has a stepped shape, and the virtual one plane 24 is closer to the second end portion 21b of the optical element 14 in the Z direction, which is the optical axis direction, and the virtual one plane 24. It is possible to manufacture the optical element 14 in which the portion 26b facing the side is closer to the first end 21a and closer to the angular displacement axis 15 than the portion 26a facing the virtual one plane 24 is. The integrated semiconductor laser device 11 including the optical element 14 having such a shape has the following advantages.

  FIG. 6 is a cross-sectional view of the housing 41 when the integrated semiconductor laser device 11 is attached to the housing 41. In the present embodiment, the semiconductor laser fixing step for fixing the integrated semiconductor laser device 11 of the present embodiment as described above to the flexible substrate 42, and the flexible substrate 42 to which the integrated semiconductor laser device 11 is fixed are housed. The integrated semiconductor laser device fixed to the flexible substrate 42 in the state of the arrow 16 around the predetermined angular displacement axis 15 in the state where the substrate is fixed to the substrate 41 and the flexible substrate 42 is fixed to the housing 41. Attached to the housing 41 with angular displacement.

  In the semiconductor laser fixing step, the integrated semiconductor laser device 11 is fixed to the flexible substrate 42 by soldering. In the substrate fixing step, the flexible substrate 42 to which the integrated semiconductor laser device 11 is fixed is fixed to the housing 41 by soldering. In the attaching process, the integrated semiconductor laser device 11 fixed to the flexible substrate 42 is attached to the housing 41. When the integrated semiconductor laser device 11 is attached in this order, it is possible to prevent the adjustment position of the optical element 14 with respect to the semiconductor laser chip 13 from being shifted by the heat of soldering.

  For example, after the integrated semiconductor laser device 11 is inserted into the housing 41 and positioned and fixed, and then the integrated semiconductor laser device 11 is soldered to the flexible substrate 42, the heat from the soldering is changed to the solder lead portion, Heat is transferred in the order of the adhesive for bonding the package 12 and the optical element 14 to the package 12 and the optical element, and the contact portion has a distortion stress due to the difference in thermal expansion coefficient of each material. There is a risk of shifting. On the other hand, when the integrated semiconductor laser device 11 is soldered to the flexible substrate 42, and then the integrated semiconductor laser device 11 is inserted into the housing 41, adjusted in position, and fixed, the heat transfer as described above is performed. Therefore, the integrated semiconductor laser device 11 can be fixed to the housing 41 in a state where the generation of distortion stress due to the difference in thermal expansion coefficient is suppressed and the adjustment position of the optical element 14 is in a suitable position.

  In this embodiment, after the flexible substrate 42 is fixed to the housing 41, the integrated semiconductor laser device 11 fixed to the flexible substrate 42 is attached to the housing 41. The flexible substrate 42 is a material having a certain degree of hardness. By attaching one end of the flexible substrate 42 to the housing 41 first, the mounting operation of the integrated semiconductor laser device 11 as a subsequent process can be stably performed. be able to. Further, since the flexible substrate 42 is directly connected to the integrated semiconductor laser device 11, attention to static electricity or the like is necessary. From this point of view, it is necessary that the end portions of the flexible substrate 42 are always assembled in the same state. Therefore, the flexible substrate 42 is fixed to the housing 12 before the integrated semiconductor laser device 11 is inserted into the housing 12.

  Further, in the present embodiment, the flexible substrate 42 is deformed, and the integrated semiconductor laser device 11 is rotated in the direction of the arrow 16 and inserted into the housing 41. If the size of the flexible substrate 42 is large, the integrated semiconductor laser device 11 can be inserted into the housing 41 without rotating. However, in the method of rotating and mounting the integrated semiconductor laser device 11 as described above, Even if the size of the flexible substrate 42 is reduced, the integrated semiconductor laser device 11 can be inserted into the housing 41. If the dimensions of the flexible substrate 42 can be reduced, it is not necessary to provide a space for accommodating the excess flexible substrate 42, and the optical pickup device can be miniaturized. Further, if the dimensions of the flexible substrate 42 can be reduced, the length of the wiring can be shortened and the responsiveness can be improved, so that the electrical characteristics are improved.

  When an integrated semiconductor laser device is mounted by such an attachment method, there is a problem that depending on the size and shape of the optical element, the housing and the optical element come into contact with each other, and it is necessary to reset the dimension of the housing. In order to solve such a problem, the optical element 14 of the present embodiment has a stepped cross section when viewed from the Y direction, and the second end of the optical element 14 in the Z direction that is the optical axis direction with respect to the virtual plane 24. A portion 26 b that is closer to the portion 21 b and faces the virtual one plane 24 is formed closer to the angular displacement axis 15 than the portion 26 a that is closer to the first end portion 21 a and faces the virtual one plane 24. With such an integrated semiconductor laser device 11, the possibility that the optical element 14 and the housing 41 are in contact with each other can be reduced.

  The integrated semiconductor laser device 11 of the present embodiment is compared with an integrated semiconductor laser including a conventional optical element 44 indicated by a two-dot chain line. Let R be the distance between the angular displacement axis 15 and the portion 26b near the second end 21b of the integrated semiconductor laser device 11 of the present embodiment and facing the virtual plane 24. Further, the distance between the angular displacement axis 15 and the portion 44a near the second end of the conventional integrated semiconductor laser device and facing the virtual plane 24 is denoted by r. In the integrated semiconductor laser device 11 of the present embodiment, the portion 26b near the second end 21b of the optical element 14 and faces the virtual plane 24 is near the second end of the conventional optical element 44, and It is closer to the angular displacement axis 15 than the portion 44 a facing the virtual plane 24. Therefore, the integrated semiconductor laser device 11 according to the present embodiment includes a portion 26b that is closer to the second end portion 21b and faces the virtual one plane 24 and the angular displacement axis 15 than the conventional integrated semiconductor laser. The distance R becomes shorter than the conventional distance r. Thereby, when the integrated semiconductor laser device 11 is angularly displaced, the region through which the optical element 14 passes can be made smaller than the region through which the conventional optical element 44 passes. The possibility that the portion 21b contacts the housing 41 can be reduced, and the housing 41 can be miniaturized as much as possible.

  In the present embodiment, no step is formed on the surface of the optical element 14 opposite to the side where the step is formed. As a result, the time required for producing the steps can be minimized, and productivity can be improved.

  As described above, when the optical element 14 of the present embodiment is used, the possibility that the housing 41 and the optical element 14 come into contact with each other when the integrated semiconductor laser device 11 is attached to the housing 41 can be reduced. Can be made thinner. As a result, the housing 41 can be miniaturized as much as possible, which can contribute to miniaturization of the optical pickup device and the optical disc device.

  Such an optical element 14 is not limited to the above configuration, and various modifications can be made.

  FIG. 7 is a perspective view of an integrated semiconductor laser device 51 according to the second embodiment of the present invention, and FIG. 8 is a cross-sectional view of the housing 41 when the integrated semiconductor laser device 51 is attached to the housing 41. The integrated semiconductor laser device 51 of the present embodiment has the same configuration as that of the integrated semiconductor laser device 11 of the first embodiment described above except that the shape of the optical element 52 is different. Are denoted by the same reference numerals, and description thereof is omitted.

  The optical element 52 of the present embodiment has a trapezoidal cross section perpendicular to the first direction, and is closer to the second end 53b of the optical element 14 in the Z direction, which is the optical axis direction, and the virtual one plane 24. The portion 54b facing the first end portion 53a is formed closer to the angular displacement axis 15 than the portion facing the virtual one plane 24. Further, in the optical element 52 of the present embodiment, the cross section viewed from the Y direction is perpendicular to the entrance surface 56a and the exit surface 56b in which the end portion 55 on one side in the X direction is a trapezoidal upper and lower base.

  Even when the integrated semiconductor laser device 51 including the optical element 52 having the trapezoidal cross section is attached to the housing 41, the optical element 52 and the housing 41 can be prevented from coming into contact with each other, and the housing is thinned. An integrated semiconductor laser device 51 can also be attached to 41. In addition, since there is no edge portion such as a staircase portion in the cross section, it is possible to minimize the influence of the light reflected at the edge portion being incident as stray light. Further, since there is no edge portion in the cross section, the antireflection film can be formed also in the cross section, and the influence of stray light can be more reliably suppressed. Such an optical element 52 having a trapezoidal cross section can be manufactured, for example, by dicing with a dicing blade having a special shape formed parallel to a trapezoidal slope to be formed by the blade surface. It can also be produced by integral resin molding using a mold.

  FIG. 9 is a perspective view of an integrated semiconductor laser device 61 according to the third embodiment of the present invention, and FIG. 10 is a cross-sectional view of the housing 41 when the integrated semiconductor laser device 61 is attached to the housing 41. The integrated semiconductor laser device 61 of the present embodiment has the same configuration as that of the integrated semiconductor laser device 11 of the first embodiment described above except that the shape of the optical element 62 is different. Are denoted by the same reference numerals, and description thereof is omitted.

  In the optical element 62 of the present embodiment, a portion 63 facing the virtual plane 24 of the optical element 62 is formed to be curved outwardly in the radial direction around the angular displacement axis 15 and is in the optical axis direction. In the Z direction, the portion 65b near the second end 64b of the optical element 14 and faces the virtual plane 24 is closer to the angular displacement axis than the portion 65b near the first end 64a and faces the virtual plane 24. It is characterized by being formed closer to 15. In the optical element 62 of the present embodiment, the portion 66 opposite to the portion facing the virtual one plane 24 is perpendicular to the incident surface 67a and the exit surface 67b.

  In this way, even when the integrated semiconductor laser device 61 including the optical element 62 having a shape including a portion whose cross section is represented by an arc is attached to the housing 41, the contact between the optical element 62 and the housing 41 can be prevented. The integrated semiconductor laser device 61 can also be attached to the thinned housing 41. In addition, since there is no edge portion such as a staircase portion in the cross section, it is possible to minimize the influence of the light reflected at the edge portion being incident as stray light. Further, since there is no edge portion in the cross section, the antireflection film can be formed also in the cross section, and the influence of stray light can be more reliably suppressed. The optical element 62 having such a shape that includes a portion whose cross section is represented by an arc can be manufactured, for example, by integral resin molding using a mold.

1 is a perspective view of an integrated semiconductor laser device 11 according to a first embodiment of the present invention. 2 is a cross-sectional view of an integrated semiconductor laser device 11. FIG. It is a top view of the translucent board | substrate 31 with which the several diffraction grating 32 was formed. It is an enlarged plan view of the translucent board | substrate 31 in which the 1st mark 33 and the 2nd mark 34 were formed. 2 is a perspective view of an optical element 14 obtained from a light transmissive substrate 31. FIG. 4 is a cross-sectional view of the housing 41 when the integrated semiconductor laser device 11 is attached to the housing 41. FIG. It is a perspective view of the integrated semiconductor laser apparatus 51 which is the 2nd Embodiment of this invention. 4 is a cross-sectional view of the housing 41 when the integrated semiconductor laser device 51 is attached to the housing 41. FIG. It is a perspective view of the integrated semiconductor laser apparatus 61 which is the 3rd Embodiment of this invention. 4 is a cross-sectional view of the housing 41 when the integrated semiconductor laser device 61 is attached to the housing 41. FIG. 1 is a perspective view of an integrated optical device 1 according to a first prior art. FIG. 2 is a cross-sectional view of the housing 6 when the integrated optical device 1 according to the first prior art is attached to the housing 6. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 51, 61 Integrated semiconductor laser apparatus 12 Package 13 Semiconductor laser chip 14, 52, 62 Optical element 15 Angular displacement axis 17 Stem 18 Cap 19 Optical window 20 Lead pin 21a, 53a, 64a 1st end part 21b, 53b, 64b Second end 22a, 56a Incident surface 22b, 56b Outgoing surface 24 Virtual plane 25a, 25b, 32 Diffraction grating 31 Translucent substrate 33 First mark 34 Second mark 35 Dielectric film 36 Acrylic resin base material 37 First groove 41 Housing 42 Flexible substrate

Claims (9)

Including a light emitting element and an optical element provided in the light emitting element so that the light emitted from the light emitting element is transmitted, around a predetermined angular displacement axis extending in a direction perpendicular to the optical axis direction of the light emitted from the light emitting element An integrated optical device that is angularly displaced and attached to a housing,
Of the first end facing the light emitting element of the optical element, the first end of the optical element in the optical axis direction with respect to a virtual plane that includes the portion farthest from the angular displacement axis and is parallel to the optical axis direction. The portion near the second end opposite to the end and facing the virtual one plane is formed closer to the angular displacement axis than the portion facing the first end and facing the virtual one plane. An integrated optical device. The optical element includes a diffraction unit that diffracts incident light,
2. The integrated optical device according to claim 1, wherein a traveling direction of the light diffracted by the diffraction unit is a direction parallel to the virtual one plane.   3. The integrated optical device according to claim 1, wherein a cross section of the optical element perpendicular to the virtual plane and the angular displacement axis is stepped.   3. The integrated optical device according to claim 1, wherein a cross section of the optical element perpendicular to the virtual plane and the angular displacement axis is trapezoidal.   3. The integrated optical device according to claim 1, wherein a portion of the optical element facing the virtual plane is curved to protrude outward in the radial direction around the angular displacement axis. Fixing the integrated optical device according to any one of claims 1 to 5 to a flexible substrate;
Fixing the flexible substrate to which the integrated optical device is fixed to the housing;
And a step of attaching the integrated optical device fixed to the flexible substrate to the housing by angular displacement about a predetermined angular displacement axis while the flexible substrate is fixed to the housing. How to install the device. A diffractive part forming step of forming a plurality of diffractive parts on a translucent substrate;
A groove forming step for forming a first groove having a predetermined width extending in a first direction between adjacent diffractive portions of the translucent substrate;
A first cutting step of forming a second groove having a width smaller than the width of the first groove, cutting the translucent substrate by penetrating the second groove in one thickness direction of the translucent substrate;
A method of manufacturing an optical element, comprising: a second cutting step of cutting between adjacent diffractive portions in a second direction orthogonal to the first direction. Before the groove formation process
The optical element according to claim 7, further comprising a mark forming step of forming a first mark for forming the first groove and a second mark for forming the second groove. Production method. The translucent substrate is
9. The method of manufacturing an optical element according to claim 7, wherein the optical element is formed including an acrylic resin base material and a dielectric film formed on a part of the surface of the acrylic resin base material.

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