A semiconductor laser of this invention, having a structure of an element composed of: carrier block layers, formed bilaterally externally of an active layer in section which is formed in the vertical direction from the surface of the element, for reducing a light guiding function of the active layer; wave guide layers provided bilaterally externally of said carrier block layers and clad layers provided so that the wave guide layers are sandwiched in between the clad layers. This invention overcomes a dilemma inherent in the conventional weakly guiding laser and LOC structured laser in terms of designing the device for controlling a guided mode. The present invention also solves the problems in terms of attaining higher outputting and a low dispersion of the radiation beams and improving a beam profile.
|
1. A semiconductor laser element including an active layer having a light guiding function comprising:
a pair of carrier block layers sandwiching said active layer, for reducing the light guiding function of said active layer, a pair of wave guide layers sandwiching said pair of carrier block layers, and a pair of clad layers sandwiching said pair of wave guide layers, wherein V2 corresponding to the normalized frequency of the wave guide layer is in the range of π/4-π, and is defined by
V2 =(πd2 /λ)·(N02 -N32)0.5 where π is the ratio of the circumference of a circle to its diameter, d2 is the effective thickness between said two clad layers, λ is the oscillation wave length, N0 is the effective refractive index of said wave guide layer, and N3 is the refractive index of said clad layer. 12. A semiconductor laser element including an active layer having a light guiding function comprising:
a pair of carrier block layers sandwiching said active layer, for reducing the light guiding function of said active layer, a pair of wave guide layers sandwiching said pair of carrier block layers, and a pair of clad layers sandwiching said pair of wave guide layers, wherein V1 relative to the normalized frequency V in a guided mode are defined by:
V1 =π·d1 /λ·(N02 -N22)0.5 and V2 corresponding to the normalized frequency of the waveguide layer is defined by: V2 =π·d2 /λ)·(N22 -N32)0.5 where π is the ratio of the circumference of a circle to its diameter, d1 is the thickness of said carrier block layer, λ is the oscillation wavelength, N2 is the refractive index of said carrier block layer, d2 is the effective thickness between said two clad layers, N0 is the effective refractive index of said wave guide layer, and N3 is the refractive index of said clad layer, wherein the relationship of V1 <V2 /10 is established. 2. The semiconductor laser element according to
3. The semiconductor laser element according to
V1 =π·d1 /λ·(N02 -N22)0.5 where π is the ratio of the circumference of a circle to its diameter, d1 is the thickness of said carrier block layer, λ is the oscillation wavelength, N2 is the refractive index of said carrier block layer, wherein the relationship of V1 <V2 /10 is established. 4. The semiconductor laser element according to
E>(2.5·103 /d12) where d1 (angstrom) is the thickness of said carrier block layer. 5. The semiconductor laser element according to
Alx Ga1-x As(0≦x<0.35). 6. The semiconductor layer element according to
V0 =π·d0 /λ·(N12 -N02)0.5 where d0 is the thickness of said active layer, when said active layer is a quantum well, V0 is defined as V0 =N·π·dw /λ(N12 -N02)0.3 where dw is the thickness of said quantum well layer, N1 is the refractive index of said quantum well layer, N0 is the refractive index of said wave guide layer, and N is the number of said quantum wells, and a relationship of (V0 /3)<V1 <5V0 (V0 /3)<V1 <V0 is established. 7. A laser device using said semiconductor laser element according to any one of
8. A semiconductor laser excitation solid-state laser device using said semiconductor laser element according to any one of
9. The semiconductor laser excitation solid-state laser device according to
10. The semiconductor laser element according to
11. The semiconductor laser element according to
2.2·103 /d12 <Δx<5.0·104 /d12 where Δx is aluminum composition difference between said carrier block layer (x1) and said wave guide layer (x2); (Δx=x1 -x2), and d1 is the thickness of said carrier block layer. |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
This application is a continuation-in-part of applicants' parent application Ser. No. 08/129,147 filed Oct. 5, 1993, now abandoned, which parent application is incorporated herein in its entirety by reference thereto.
The present invention relates generally to industrial fields in which high-output semiconductor lasers are employed for communications, optical recording on optical disks or the like, laser printers, laser medical treatments, laser machining, etc. The present invention relates, more particularly, to a high-output semiconductor laser for a solid-state laser excitation requiring laser beams having an enhanced output and a small radiation angle or for a harmonic conversion element excitation and also to a laser device using this semiconductor laser.
It has been desired in many sectors that the output of the semiconductor laser be enhanced. A factor for hindering the output enhancement per single mode of the semiconductor laser is an exit surface fusion caused by the laser beam which is called catastrophic optical damage (COD). The COD is conspicuous especially in an AlGaAs laser. Paying attention mainly to a reduction of a power density of the laser by expanding a laser guided mode, a weakly guiding laser having a thin active layer or a separate confinement type laser known as a large optical cavity (LOC) structure has hitherto been examined.
Based on such a structure, however, a strong correlation exists between a refractive index and a bandgap of each mixed crystal in a variety of laser materials ranging from the AlGaAs system. It is therefore impossible to independently control a carrier confinement and an optical confinement in a waveguide.
In particular, the expansion of the guided mode requires the thin active layer in either the LOC structured laser or the weakly guiding laser for the output enhancement. Further, a wide active layer is needed for obtaining a high gain for oscillations in the expanded guided mode. A self-contradiction thus exists therein. As a matter of fact, a limit of the mode expansion in an epitaxial direction by the above-mentioned methods is approximately 1 μm at the maximum. A limit of the output is on the order of 100 mW per single mode.
Besides, in the weakly guiding laser having the thin active layer, the guided mode in the laminated direction exhibits an exponential function profile. Hence, a radiation density in the active layer where the catastrophic optical damage is caused is high as compared with the whole beam intensity. This is disadvantageous for the output enhancement. Besides, the guided mode has tails drawn deeply in the clad layers, and hence there is needed a growth of the clad layers that is considerably thick for the expansion of the guided mode.
In addition, both the guided mode (near-field pattern) and a beam radiation angle (far-field pattern) deviate largely from the Gaussian beam conceived as ideal one. There exists a problem in terms of a convergence of the beams in multiple applications.
On the other hand, there have also been examined lasers based on a so-called window structure in which the vicinity of an exit surface where a COD may occur is made transparent to the laser emission beam and a structure where a carrier injection is not effected in the vicinity of the exit surface. Those structures generally present, however, such problems that the astigmatism increases in addition to a complicated manufacturing process.
Further, there has been made an attempt to manufacture the high-output laser in the single mode by an optical feedback between a multiplicity of semiconductor lasers. The problem is, however, that the device becomes complicated.
It is an object of the present invention in view of the fact that multi-layered thin films have been easily formed by the molecular beam epitaxial (MBE) method, the metal organic chemical vapor deposition (MOCVD) method, etc. in recent years to solve the problems inherent in the conventional weakly guiding lasers and the LOC structured lasers in terms of overcoming the dilemma in designing the device for controlling the guided mode, attaining the output enhancement, the low dispersion of the radiation beams and improving the beam profile.
According to the present invention, barrier layers (hereinafter referred to as "carrier block layers") having barrier heights and widths enough to cancel a guiding characteristic of an active layer and perform a carrier confinement in the active layer are inserted on both sides of the active layer of an ordinary double hereto laser or a quantum well laser. It is therefore possible to perform the confinement in the guided mode and independently design an active layer thickness required for oscillations.
On this occasion, a guiding function of the active layer can be cancelled by the carrier block layers by reducing the thickness of the active layer region and the thickness of the carrier block layers to 1/Nth (N=2 to 9) or less of the oscillation wavelength. Under such conditions, the wave guide layers are further formed, and clad layers having a small difference of refractive index are formed at both sides of the wave guide layer for the purpose of controlling only light guiding. Formed alternatively are wide wave guide layers based on a graded-index structure of a straight line, a quadratic curve, etc. It is thus possible to design the guided mode completely independently of the active layer design parameters, thereby obtaining a stable mode approximate to the Gaussian beams and the radiation beams having the high output and low dispersion angle.
With the intention of enhancing the output of the semiconductor laser by avoiding the Al0.38 Ga0.62 As Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 165 angstrom
Composition: Al0.38 Ga0.62 As Al0.30 Ga0.50 As
FIG. 21 illustrates a guided mode profile (near-field patterns) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 22 shows a measured result in the radiation mode.
As illustrated in FIG. 3, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 2.0 μm
Composition: Al0.31 Ga0.69 As
p-type light wave guide layer 6
Thickness: 0.93 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.93 μm
Composition: Al0.31 Ga0.70 As
n-type clad layer 1
Thickness: 2.0 μm
Composition: Al0.31 Ga0.69 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 is formed such that 8-layered quantum well layers 13 are each partitioned by the barrier layers 14 as shown in exploded view between side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in an area sandwiched in between the p-type carrier block layer 5 and the n-type barrier layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 330 angstrom
Composition: Al0.30 Ga0.70 As Al0.50 Ga0.50 As
FIG. 21 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 22 shows a measured result in the radiation mode.
As illustrated in FIG. 4, an n-type inversion layer 15 is provided between the p-type clad layer 7 and the p-type light wave guide layer 6. With the placement of this n-type inversion layer, the current can be narrowed down in the lateral direction in the vicinity of the active layer 4.
Namely, the light is confined also in the lateral direction owing to the n-type inversion layer 15, thereby making it possible to attain a stabilized off-axial mode.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 0.8 μm
Composition: Al0.35 Ga0.65 As
n-type inversion layer 15
Thickness: 0.2 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.93 μm
Composition: Al0.35 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.93 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 8-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 21 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 22 shows a measured result in the radiation mode.
As illustrated in FIG. 6, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 100 angstrom
Composition: Al0.38 Ga0.62 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 100 angstrom
Composition: Al0.38 Ga0.62 As
FIG. 23 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 24 shows a measured result in the radiation mode.
As illustrated in FIG. 6, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.35 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 200 angstrom
Composition: Al0.38 Ga0.62 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 200 angstrom
Composition: Al0.38 Ga0.62 As
FIG. 23 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 24 shows a measured result in the radiation mode.
As illustrated in FIG. 7, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.35 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 330 angstrom
Composition: Al0.38 Ga0.62 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 330 angstrom
Composition: Al0.38 Ga0.62 As
FIG. 23 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 24 shows a measured result in the radiation mode.
As illustrated in FIG. 8, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 500 angstrom
Composition: Al0.38 Ga0.62 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 500 angstrom
Composition: Al0.38 Ga0.62 As
FIG. 23 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 24 shows a measured result in the radiation mode.
As illustrated in FIG. 9, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 50 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As Al0.50 Ga0.50 As
FIG. 25 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 26 shows a measured result in the radiation mode.
As illustrated in FIG. 10, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 25 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 26 shows a measured result in the radiation mode.
As illustrated in FIG. 11, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.30 Ga0.70 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 500 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
n-type carrier block layer 3
Thickness: 500 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 25 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 26 shows a measured result in the radiation mode.
As illustrated in FIG. 12, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 50 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 50 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 27 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 28 shows a measured result in the radiation mode.
As illustrated in FIG. 13, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 135 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 135 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 27 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 28 shows a measured result in the radiation mode.
As illustrated in FIG. 14, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 200 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 200 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 27 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 28 shows a measured result in the radiation mode.
As illustrated in FIG. 15, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 330 angstrom
Composition: Al0.50 Ga0.50 As
FIG. 27 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 28 shows a measured result in the radiation mode.
As illustrated in FIG. 16, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 50 angstrom
Composition: Al0.65 Ga0.35 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 50 angstrom
Composition: Al0.65 Ga0.35 As
FIG. 29 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 30 shows a measured result in the radiation mode.
As illustrated in FIG. 17, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 100 angstrom
Composition: Al0.35 Ga0.65 As Al0.65 Ga0.35 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 100 angstrom
Composition: Al0.35 Ga0.65 As Al0.65 Ga0.35 As
FIG. 29 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 30 shows a measured result in the radiation mode.
As illustrated in FIG. 18, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 200 angstrom
Composition: Al0.65 Ga0.35 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 200 angstrom
Composition: Al0.65 Ga0.35 As
FIG. 29 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 30 shows a measured result in the radiation mode.
As illustrated in FIG. 19, the n-type buffer layer 10 having a thickness of 0.5 μm is formed on the n-type substrate 8 composed of GaAs. Formed sequentially on this layer are the n-type clad layer 1, the n-type light wave guide layer 2, the n-type carrier block layer 3, the active layer 4, the p-type carrier block layer 5, the p-type light wave guide layer 6 and the p-type clad layer 7. The n-type cap layer 11 is formed as an uppermost layer thereon.
The following are concrete configurations of the respective layers.
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
p-type light wave guide layer 6
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type light wave guide layer 2
Thickness: 0.46 μm
Composition: Al0.25 Ga0.75 As
n-type clad layer 1
Thickness: 1.0 μm
Composition: Al0.35 Ga0.65 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that the 4-layered quantum well layers 13 are each partitioned by the barrier layers 14 between the side barrier layers 12 deposited on the inner walls of the respective carrier block layers 5, 3 in the area sandwiched in between the p-type carrier block layer 5 and the n-type carrier block layer 3. The concrete configurations of this active layer 4 are given as follows:
p-type carrier block layer 5
Thickness: 280 angstrom
Composition: Al0.65 Ga0.35 As
Side barrier layer 12
Thickness: 25 angstrom
Composition: Al0.25 Ga0.75 As
Quantum well layer 13
Thickness: 55 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.25 Ga0.75 As
n-type carrier block layer 3
Thickness: 280 angstrom
Composition: Al0.65 Ga0.35 As
FIG. 29 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 30 shows a measured result in the radiation mode.
FIG. 20 is a schematic plan view showing a composition of a quantum well type laser element based on a conventional structure which is manufactured for comparisons with the above-mentioned Embodiments 1-18.
The following are concrete configurations of the respective layers,
n-type cap layer 11
Thickness: 0.3 μm
Composition: GaAs
p-type clad layer 7
Thickness: 1.5 μm
Composition: Al0.65 Ga0.35 As
n-type clad layer 1
Thickness: 1.5 μm
Composition: Al0.65 Ga0.35 As
n-type buffer layer 10
Thickness: 0.5 μm
Composition: GaAs
n-type substrate 8
Composition (100) GaAs
The active layer 4 as shown in exploded view is formed such that 4-layered quantum well layers 13 are partitioned by barrier layers 14 in an area sandwiched in between side barrier layers 12. The concrete configurations of this active layer 4 are given as follows:
Side barrier layer 12
Thickness: 120 angstrom
Composition: Al0.30 Ga0.70 As
Quantum well layer 13
Thickness: 50 angstrom
Composition: GaAs
Barrier layer 14
Thickness: 50 angstrom
Composition: Al0.30 Ga0.70 As
FIG. 21 illustrates a guided mode profile (near-field pattern) in the direction vertical to the epitaxy layer with respect to the structure shown in this embodiment. FIG. 22 shows a measured result in the radiation mode.
As obvious from FIG. 21, the weakly guiding semiconductor laser exhibits a center-pointed characteristic curve having exponential function tails on both sides. In contrast, the Embodiments 1-18 exhibit characteristic forms similar to a Gaussian beam. For this reason, using the semiconductor laser in the present embodiment decreases the beam intensity in the active layer 4 (mode center), as shown in FIG. 21, where an optical damage is caused even with a mode expansion to the same extent as that in the prior arts. As shown by the measured results in Table 1 which follows, a level of the catastrophic optical damage (COD) can be remarkably raised. Namely, a reduction in radiation angle and a remarkable improvement in the level of the optical damage in the present embodiments 1-3 become more apparent than in the comparative example. Note that an emission wavelength (angstrom) of the laser is approximately 8000 angstrom in Table 1. Further, the optical damage level and the slope efficiency are each optical outputs per edge surface.
| TABLE 1 |
| __________________________________________________________________________ |
| RADIATION |
| COD THRESHOLD |
| SLOFE |
| NORMALIZED |
| ANGLE LEVEL |
| CURRENT |
| EFFICIENCY |
| LD TYPE FREQUENCY |
| Θ⊥Θ∥ |
| (mW) |
| (mA) (mW/mA) |
| __________________________________________________________________________ |
| EMBODIMENT I 1.6 25° |
| 250 90 0.5 |
| STRUTURE IN FIG. 2 5° |
| EMBODIMENT 2 1.6 14° |
| 500 300 0.5 |
| STRUCTURE IN FIG. 3 4° |
| EMBODIMENT 3 3.5 18° |
| 400 250 0.5 |
| STRUCTURE IN FIG. 4 5° |
| COMPARATIVE EXAMPLE |
| 0.28 22° |
| 100 75 0.4 |
| STRUCTURE IN FIG. 20 8° |
| __________________________________________________________________________ |
In the industrial fields where the high-output semiconductor laser is employed for communications, optical recording on optical disks or the like, laser printers, laser medical treatments and laser machining, etc. according to the present invention, the high-efficiency semiconductor laser exhibiting a good beam profile at the low radiation beam angle can be obtained. Besides, it is possible to manufacture the high-output semiconductor laser by avoiding the concurrent optical damage of the edge surface with a simple structure. Especially in the Alx Ga1-x As semiconductor laser, the Al composition of the wave guide layer can be reduced, thereby facilitating the manufacturing process.
For this reason, the element of the present invention can be utilized in the form of the high-efficiency semiconductor laser device. Furthermore, the semiconductor laser can be used as an excitation source of a solid-state laser. The solid-state laser may involve the use of laser mediums such as Nd:YAG and Nd:YLF. If the semiconductor laser is employed as an excitation source of the solid-state laser, the problem is a method of connecting the semiconductor laser to the laser medium. Generally, excitation beams from the semiconductor laser are focused at a high efficiency through such a lens as to mode-match an excitation volume of the semiconductor laser with a mode volume of the laser oscillator.
In the laser element according to this invention, the beams may be focused by use of the lens as described above. As illustrated in FIGS. 32 and 33, the excitation beams from a semiconductor laser element 21 can be made to strike on a laser medium 23 without effecting any optical processing on the excitation beams from the semiconductor laser element 21. Incidentally, the numeral 24 designates an output mirror. Note that FIG. 32 shows a direct-connection type wherein the semiconductor laser element 21 is connected directly to the laser medium 23, while FIG. 33 illustrates a fiber connection type semiconductor laser excitation solid-state laser device in which the semiconductor laser element 21 is connected via an optical fiber 22 to the laser medium 23.
Yoshida, Yuji, Fujimoto, Tsuyoshi, Muro, Kiyofumi, Ishizaka, Shoji, Yamada, Yoshikazu
| Patent | Priority | Assignee | Title |
| 7483461, | Apr 28 2006 | SUMITOMO ELECTRIC INDUSTRIES, LTD | Semiconductor laser diode with a plurality of optical guiding layers |
| Patent | Priority | Assignee | Title |
| 4328469, | Jan 15 1979 | Xerox Corporation | High output power injection lasers |
| 5172384, | May 03 1991 | Motorola, Inc. | Low threshold current laser |
| 5319660, | May 29 1992 | CURATORS OF THE UNIVERSITY OF MISSOURI, THE | Multi-quantum barrier laser |
| EP348941, | |||
| JP2150087, | |||
| JP3071679, | |||
| JP3076288, | |||
| JP3290984, | |||
| JP56164588, | |||
| JP58216489, | |||
| JP60133781, | |||
| JP60164379, | |||
| JP6115385, | |||
| JP62173788, | |||
| JP62188392, | |||
| JP6274517, |
| Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
| Oct 01 1997 | Mitsui Petrochemical Industries, Ltd | Mitsui Chemicals, Inc | CHANGE OF NAME SEE DOCUMENT FOR DETAILS | 009570 | /0124 | |
| Nov 14 1997 | Mitsui Chemicals, Inc. | (assignment on the face of the patent) | / |
| Date | Maintenance Fee Events |
| Apr 23 2003 | M1552: Payment of Maintenance Fee, 8th Year, Large Entity. |
| Apr 20 2007 | M1553: Payment of Maintenance Fee, 12th Year, Large Entity. |
| Date | Maintenance Schedule |
| Dec 07 2002 | 4 years fee payment window open |
| Jun 07 2003 | 6 months grace period start (w surcharge) |
| Dec 07 2003 | patent expiry (for year 4) |
| Dec 07 2005 | 2 years to revive unintentionally abandoned end. (for year 4) |
| Dec 07 2006 | 8 years fee payment window open |
| Jun 07 2007 | 6 months grace period start (w surcharge) |
| Dec 07 2007 | patent expiry (for year 8) |
| Dec 07 2009 | 2 years to revive unintentionally abandoned end. (for year 8) |
| Dec 07 2010 | 12 years fee payment window open |
| Jun 07 2011 | 6 months grace period start (w surcharge) |
| Dec 07 2011 | patent expiry (for year 12) |
| Dec 07 2013 | 2 years to revive unintentionally abandoned end. (for year 12) |