JP3587747B2 - Semiconductor laser device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor laser device, and more particularly, to a semiconductor laser device used in an optical pickup system for an optical disk.
[0002]
[Prior art]
As a conventional general semiconductor laser device, a semiconductor laser device as shown in FIG. 7 is known.
The semiconductor laser device 101 shown in FIG. 7 includes a metal stem 102, a block 103 provided on the upper surface of the stem 102, a laser chip 104, a light receiving element 105, lead pins 106a, 106b, 106c, and metal wires 107a, 107b. The laser chip 104 is mounted on the side surface of the block 103.
[0003]
Note that reference numerals 108a and 108b indicate laser beams emitted from the laser chip 104 in two directions, respectively.
Both ends of the metal wire 107a are connected to the laser chip 104 and the lead pins 106a by wire bonding, and similarly, both ends of the metal wire 107b are connected to the light receiving element 105 and the lead pins 106b by wire bonding.
[0004]
The laser chip 104 emits a laser beam 108a in a direction perpendicular to a light receiving element 105 disposed on the upper surface of the stem 102. The light receiving element 105 receives the laser light 108a emitted from the laser chip 104 and Monitor the output of
The monitoring result of the laser beam 108a obtained from the light receiving element 105 is fed back to a semiconductor laser driving circuit (not shown), and the intensity of the laser beam 108b is controlled.
[0005]
[Problems to be solved by the invention]
Such a conventional semiconductor laser device needs to have a block portion on the upper surface of the stem to support the laser chip, and the structure becomes complicated.
Further, since the laser chip and the light receiving element are electrically connected to the respective lead terminals using metal wires, the connection process is complicated, and the work time and mounting accuracy are problematic.
[0006]
The present invention has been made in view of such circumstances, and provides a high-quality semiconductor laser device having a simple structure and manufacturing process by mounting a laser chip and a light receiving element on a substrate. .
[0007]
[Means for Solving the Problems]
The present invention relates to a semiconductor laser device for irradiating an object with laser light, a substrate made of glass or resin having translucency, a laser chip for emitting first and second laser lights in two different directions, and a laser chip. a first wiring pattern for supplying power to the monitoring light-receiving element for monitoring the output of the laser chip, and a second wiring pattern electrically connected to the monitor light-receiving element, the first wiring pattern of the heat generated by the laser chip The laser chip is formed over substantially the entire surface of the substrate so as to dissipate heat, and defines a light-transmitting portion. Wherein the second wiring pattern is provided on the back surface of the substrate, and the light receiving element for monitoring is a semiconductor laser device provided on the back surface of the substrate so as to receive the first laser light transmitted through the light transmitting portion. It is intended to provide.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The semiconductor laser device of the present invention, the substrate is formed of glass or resin having translucency.
Examples of the glass here include soda glass, quartz glass, borosilicate glass, and the like.
Examples of the resin include an acrylic resin and an epoxy resin.
[0009]
With such a configuration, an arbitrary position on the substrate can be used as a light-transmitting portion, which is more preferable as the substrate of the semiconductor laser device of the present invention.
However, by forming a part of a substrate having a normal light-shielding property with a light-transmitting material or performing processing such as making a hole, it is possible to use that part as a light-transmitting part. Needless to say.
[0010]
Further, in the semiconductor laser device of the present invention, the first wiring pattern is formed over the entire surface of the substrate so as to radiate heat generated by the laser chip .
This is, by increasing the surface area to the substrate surface of the wiring pattern, and means to actively radiate heat generated in the laser chip.
Increasing the area of the wiring pattern also serves as a light shielding function to prevent the light receiving element from receiving extra light other than arbitrary laser light.
[0011]
In the semiconductor laser device of the present invention, the second wiring pattern may further include a light receiving element connection bump on a part thereof.
[0012]
Further, in the semiconductor laser device of the present invention, the laser chip on the substrate surface may be covered with a translucent resin.
Further, the monitor light receiving element on the back surface of the substrate may be covered with a light shielding resin. With this configuration, the semiconductor laser device can be easily protected from an external contact object or the like.
The light-transmitting resin is used on the substrate surface to transmit laser light, and the light-shielding resin is used on the back surface of the substrate to prevent the light receiving element from receiving extra light other than the arbitrary laser light. To do that.
[0013]
Further, the semiconductor laser device of the present invention further includes a diffraction element, a reflected light receiving element, and a third wiring pattern electrically connected to the reflected light receiving element, and the diffraction element is emitted from the laser chip toward an object. The second laser beam irradiates the target object through the diffraction element, and after being reflected from the target object, is transmitted again through the light-transmitting portion of the substrate through the diffraction element. The third wiring pattern may be provided on the back surface of the substrate so as to receive the second laser light transmitted through the optical unit, and the third wiring pattern may be provided on the back surface of the substrate.
[0014]
In such a case, the third wiring pattern may further include a light receiving element connection bump on a part thereof.
Further, the diffraction element may be supported on the substrate surface via a spacer.
Further, the reflected light receiving element may be formed integrally with the monitoring light receiving element. Further, the monitoring light receiving element and the reflected light receiving element on the back surface of the substrate may be covered with a light shielding resin.
[0015]
Further, the semiconductor laser device of the present invention further includes a diffraction element, a reflected light receiving element, and a third wiring pattern electrically connected to the reflected light receiving element, and the diffraction element is emitted from the laser chip toward an object. A second laser beam that irradiates the object through the diffractive element, reflects the object and then re-enters the object through the diffractive element, and the reflected light receiving element is a second laser beam incident through the diffractive element. The third wiring pattern may be provided on the substrate surface so as to receive light, and the third wiring pattern may be provided on the substrate surface.
[0016]
In such a case, the diffraction element may be supported on the surface of the substrate via a spacer.
Further, the monitor light receiving element on the back surface of the substrate may be covered with a light shielding resin.
[0017]
【Example】
Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. The present invention is not limited by the embodiment.
[0018]
Example 1
First Embodiment A first embodiment of the present invention will be described with reference to FIGS.
As shown in these figures, a semiconductor laser device 1 for irradiating an optical disk (not shown) with a laser beam includes a glass transparent substrate 2 having a light transmitting portion 3, a first laser beam 5a and a second laser beam. A laser chip 4 for emitting light 5b in two different directions, wiring patterns (first wiring patterns) 6a and 6b for supplying power to the laser chip 4, a monitor light receiving element 8 for monitoring the output of the laser chip 4, and a monitor Wiring patterns (second wiring patterns) 7a and 7b electrically connected to the light receiving element 8.
[0019]
The wiring patterns 6a and 6b are formed on the front surface of the transparent substrate 2, the wiring patterns 7a and 7b are formed on the back surface of the transparent substrate 2, respectively, and the light transmitting portion 3 is formed between the wiring patterns 6a and 6b and between the wiring patterns 7a and 7b. It is formed in the cut.
The laser chip 4 has its two electrodes (not shown) connected to the wiring patterns 6a and 6b by a conductive paste 9, and the first laser light 5a emitted from the laser chip 4 passes through the light transmitting portion 3. The second laser beam 5b is disposed on the surface of the transparent substrate 2 so as to irradiate an optical disk (not shown).
[0020]
On the other hand, the monitor light receiving element 8 has its two electrodes (not shown) electrically connected to the wiring patterns 7a and 7b via the bumps 10, respectively, and the first laser beam 5a transmitted through the light transmitting section 3. Is disposed on the back surface of the transparent substrate 2 so as to receive light.
[0021]
As shown particularly in FIG. 2, the reason why the wiring patterns 6a and 6b cover substantially the entire surface of the transparent substrate 2 is that the surface area of the wiring patterns 6a and 6b is increased and the laser chip 4 (FIG. This is for dissipating the heat generated in ()). Increasing the area of the wiring patterns 6a and 6b means that extra light other than the first laser light 5a is applied to the monitoring light-receiving element 8 provided on the back surface of the transparent substrate 2 as shown in FIG. There is also an effect of preventing incidence.
[0022]
Further, as shown in FIG. 1, the surface of the transparent substrate 2 is covered with a transparent resin 11 to protect the laser chip 4 from external contacts or the like (not shown).
On the other hand, the back surface of the transparent substrate 2 is covered with a light-shielding resin 12, the monitor light-receiving element 8 is protected from an external contact or the like (not shown), and receives extra light other than the first laser light 5a. Not to be.
[0023]
In the semiconductor laser device 1 configured as described above, the intensity of the first laser light 5a emitted from the laser chip 4 is monitored by the monitoring light receiving element 8 as shown in FIG.
On the other hand, the second laser beam 5b irradiates the optical disk and is used for reading optical information of the optical disk.
[0024]
Example 2
Second Embodiment A second embodiment of the present invention will be described with reference to FIG.
In the semiconductor laser device 21 shown in FIG. 3, a metal cap 34 having a window glass 33 is attached to the surface of a transparent substrate 22, thereby protecting the laser chip 24 from external contact objects and the like.
Further, by attaching the metal cap 34, the noise-reducing performance of the semiconductor laser device 21 is also improved.
Other configurations are the same as those of the semiconductor laser device 1 according to the first embodiment shown in FIGS. 1 and 2.
[0025]
Example 3
Third Embodiment A third embodiment of the present invention will be described with reference to FIG.
The semiconductor laser device 41 shown in FIG. 4 includes a cylindrical spacer 56 on the surface of a transparent substrate 42, and a glass plate 55 is attached to the upper end thereof, thereby protecting the laser chip 44 from external contact objects and the like. .
Other configurations are the same as those of the semiconductor laser device 1 according to the first embodiment shown in FIGS. 1 and 2.
[0026]
Example 4
Embodiment 4 of the present invention will be described with reference to FIG.
The semiconductor laser device 61 shown in FIG. 5 includes a glass transparent substrate 62 having light transmitting portions 63a and 63b, a laser chip 64 that emits the first laser light 65a and the second laser light 65b in two different directions, Wiring patterns (first wiring patterns) 66a and 66b for supplying power to the laser chip 64, a diffractive element 77, a light receiving element 68 having two light receiving sections 68a and 68b, and a wiring pattern electrically connected to the light receiving element 68 ( (Second and third wiring patterns) 67a, 67b, 67c.
[0027]
As shown in FIG. 5, the wiring patterns 66a, 66b are formed on the front surface of the transparent substrate 62, the wiring patterns 67a, 67b, 67c are formed on the rear surface of the transparent substrate 62, respectively, and the light transmitting portion 63a is formed between the wiring patterns 66a, 66b. It is formed at a break and a break between the wiring patterns 67a and 67b.
On the other hand, the light transmitting portion 63b is formed at a break formed in a part of the wiring pattern 66b and at a break between the wiring patterns 67b and 67c.
The laser chip 64 has its two electrodes (not shown) connected to the wiring patterns 66a and 66b by a conductive paste 69, and the first laser light 65a emitted from the laser chip 64 passes through the first light transmitting portion 63a. It is arranged on the surface of the transparent substrate 62 so that the transmitted second laser beam 65b irradiates an optical disk (not shown).
[0028]
Further, the diffraction element 77 irradiates the optical disk with the second laser light 65b emitted from the laser chip 64 via the diffraction element 77, and the reflected laser light 65c reflected from the optical disk again transmits the transparent substrate 62 via the diffraction element 77. Is provided on the surface of the transparent substrate 62 via the cylindrical spacer 76 so as to transmit through the light transmitting portion 63b.
On the other hand, the light receiving element 68 has its three electrodes (not shown) electrically connected to the wiring patterns 67a, 67b, 67c via the bumps 70, and the light receiving section 68a receives the first laser light 65a by the reflected laser. The light 65c is arranged on the back surface of the transparent substrate 62 so that the light receiving portions 68b receive the light 65c.
In other words, the light receiving element 68 of the fifth embodiment includes a monitoring light receiving element that monitors the output of the laser chip and a reflected light receiving element that receives the reflected laser light emitted from an object such as an optical disk and reflected therefrom. It is configured integrally.
[0029]
Further, as shown in FIG. 5, the back surface of the transparent substrate 62 is covered with a light-shielding resin 72, the light receiving element 68 is protected from an external contact or the like (not shown), and the first laser light 65a and the reflection light are reflected. Extra light other than the laser light 65c is not received.
[0030]
In the semiconductor laser device 61 configured as described above, the intensity of the first laser light 65a emitted from the laser chip 64 is monitored by the light receiving section 68a of the light receiving element 68 as shown in FIG.
On the other hand, after irradiating the optical disk, the second laser light 65b is reflected and becomes a reflected laser light 65c, which is received by the light receiving section 68b of the light receiving element 68, and the optical information is read.
[0031]
Example 5
A fifth embodiment of the present invention will be described with reference to FIG.
A semiconductor laser device 81 shown in FIG. 6 includes a glass transparent substrate 82 having a light transmitting portion 83, a laser chip 84 for emitting a first laser beam 85a and a second laser beam 85b in two different directions, The wiring patterns (first wiring patterns) 86a and 86b for feeding power to the wiring 84, the diffraction element 97, the monitor light receiving element 88a, the reflected light receiving element 88b, and the wiring pattern electrically connected to the monitor light receiving element 88a ( (A second wiring pattern) 87a, 87b and a wiring pattern (third wiring pattern) 86c electrically connected to the reflected light receiving element 88b.
Note that the wiring pattern 86b is also electrically connected to the reflected light receiving element 88b.
[0032]
As shown in FIG. 6, the wiring patterns 86a, 86b, and 86c are formed on the front surface of the transparent substrate 82, the wiring patterns 87a and 87b are formed on the back surface of the transparent substrate, respectively, and the light transmitting portion 83 is a cut between the wiring patterns 86a and 86b. And it is formed at the break between the wiring patterns 87a and 87b.
The laser chip 84 has its two electrodes (not shown) connected to the wiring patterns 86a and 86b by a conductive paste 89, and the first laser light 85a emitted from the laser chip 84 passes through the light transmitting portion 83. The second laser beam 85b is arranged on the surface of the transparent substrate 82 so as to irradiate an optical disk (not shown).
[0033]
Further, the diffraction element 97 irradiates the optical disc with the second laser beam 85b emitted from the laser chip 84 via the diffraction element 97, and the reflected laser beam 85c reflected from the optical disc again passes through the diffraction element 97 to the semiconductor laser device. It is provided on the surface of the transparent substrate 82 via a cylindrical spacer 96 so as to be incident into the inside 81.
The monitor light-receiving element 88a has its two electrodes (not shown) electrically connected to the wiring patterns 87a and 87b via bumps 90, and receives the first laser beam 85a from the back surface of the transparent substrate 82. Are located in
On the other hand, the reflected light receiving element 88b has its two electrodes (not shown) connected to the wiring patterns 86b and 86c by a conductive paste 89, and receives the reflected laser light 85c incident on the semiconductor laser device 81. Are disposed on the surface of the transparent substrate 82.
[0034]
As shown in FIG. 6, the back surface of the transparent substrate 82 is covered with a light-shielding resin 92, and the monitor light-receiving element 88a is protected from an external contact object or the like (not shown) and the first laser light 85a. Extra light other than the above is not received.
[0035]
The function of the semiconductor laser device 81 thus configured is the same as that of the semiconductor laser device 61 of the above-described fourth embodiment shown in FIG. 5, but is different from the monitoring light receiving element 88a that receives the first laser light 85a. Since the reflected light receiving element 88b for receiving the reflected laser light 85c is provided independently at a different mounting position, the accuracy of the optical system is improved.
[0036]
【The invention's effect】
According to the present invention, the structure and the manufacturing process of the semiconductor laser device can be simplified, and the quality can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment 1 of the present invention.
FIG. 2 is a plan view showing a transparent substrate of the semiconductor laser device shown in FIG. 1 and a wiring pattern on the surface thereof.
FIG. 3 is a sectional view showing an embodiment 2 of the present invention.
FIG. 4 is a sectional view showing an embodiment 3 of the present invention.
FIG. 5 is a sectional view showing an embodiment 4 of the present invention.
FIG. 6 is a sectional view showing an embodiment 5 of the present invention.
FIG. 7 is a perspective view showing a conventional semiconductor laser device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Semiconductor laser device 2 ... Transparent substrate 3 ... Translucent part 4 ... Laser chip 5a ... 1st laser beam 5b ... 2nd laser beam 6a, 6b, 7a, 7c. ..Wiring pattern 8 Monitor light-receiving element 9 Conductive paste 10 Bump 11 Transparent resin 12 Light-shielding resin

Claims (10)

In a semiconductor laser device that irradiates a laser beam to an object, a substrate made of glass or resin having a light- transmitting property, a laser chip that emits first and second laser beams in two different directions, A first wiring pattern, a monitoring light receiving element for monitoring an output of the laser chip, and a second wiring pattern electrically connected to the monitoring light receiving element, wherein the first wiring pattern radiates heat of the laser chip. A laser chip is formed over substantially the entire surface of the substrate to define a light- transmitting portion, and the laser chip is provided on the substrate surface such that a first laser beam passes through the light-transmitting portion and a second laser beam irradiates an object. A semiconductor laser device in which two wiring patterns are provided on the back surface of the substrate, and the light receiving element for monitoring is provided on the back surface of the substrate so as to receive the first laser light transmitted through the light transmitting portion. 2. The semiconductor laser device according to claim 1, wherein the second wiring pattern further includes a light receiving element connection bump on a part thereof. 2. The semiconductor laser device according to claim 1, wherein the laser chip on the surface of the substrate is covered with a translucent resin. A diffraction element, a reflected light receiving element, and a third wiring pattern electrically connected to the reflected light receiving element, wherein the second laser beam emitted from the laser chip toward the object is transmitted through the diffraction element. The reflected light receiving element is provided so as to pass through the light transmitting portion of the substrate again through the diffraction element after being reflected from the object and reflected by the object. 2. The semiconductor laser device according to claim 1, wherein the third wiring pattern is provided on the back surface of the substrate so as to receive light. 5. The semiconductor laser device according to claim 4 , wherein the third wiring pattern further includes a light receiving element connection bump on a part thereof. 5. The semiconductor laser device according to claim 4 , wherein the reflected light receiving element is formed integrally with the monitoring light receiving element. The semiconductor laser device according to claim 4, the monitoring light receiving element and the reflection light receiving Hikarimoto child back surface of the substrate is covered with a light-shielding resin. A diffraction element, a reflected light receiving element, and a third wiring pattern electrically connected to the reflected light receiving element, wherein the second laser beam emitted from the laser chip toward the object is transmitted through the diffraction element. The reflected light receiving element is provided on the substrate surface so as to receive the second laser light incident via the diffractive element after being reflected from the object and irradiating the object through the diffractive element. 2. The semiconductor laser device according to claim 1, wherein the third wiring pattern is provided on a surface of the substrate. The semiconductor laser device according to claim 4 or 8 diffractive element is supported via a spacer to the substrate surface. Substrate back surface of the monitoring light-receiving element, a semiconductor laser device according to claim 1 or 8 covered with light-shielding resin.

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