JP3034087B2 - Semiconductor laser pumped coherent light source - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser pumped coherent light source, and more particularly to a semiconductor laser pumped coherent light source utilizing sum frequency mixing.

[0002]

2. Description of the Related Art Conventionally, techniques in such a field include:
For example, JP-A-1-214082, JP-A-2-2898
No. 0 is known. These have a semiconductor laser light source for excitation and a semiconductor laser light source to be modulated, and realize a semiconductor laser excitation coherent light source by using sum frequency mixing.

[0003]

However, in these prior arts, since the laser medium for laser oscillation and the nonlinear optical crystal for sum frequency mixing are separate crystals, the generation efficiency of sum frequency mixed light is reduced. Low. For this reason, it is necessary to increase the power of the semiconductor laser light source, and the convenience is impaired. In addition, there is a problem in that it is difficult to reduce the size, weight, and size.

Accordingly, an object of the present invention is to provide a semiconductor laser-pumped coherent light source that is highly efficient and is suitable for miniaturization, lightness, and compactness.

[0005]

A semiconductor laser-pumped coherent light source according to the present invention comprises a crystal of a laser medium having non-linear optical characteristics, and a pump laser beam incident from an end face on one side of the crystal. First to cause laser oscillation
A semiconductor laser light source, and a second semiconductor laser light source that receives a modulated laser beam from another end face on one side of the crystal body and generates sum frequency mixing with laser oscillation light,
The other surface side of the crystal is finished so as to reflect the excitation laser light and the modulated laser light and transmit the sum frequency mixed light.

[0006]

According to the present invention, since laser oscillation and sum frequency mixing are realized by a single crystal, high efficiency can be achieved. Since the laser beam is incident from one surface of the crystal, the other surface of the crystal is used as a reflection end surface to achieve compactness.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a configuration diagram of a semiconductor laser pumped coherent light source according to a first embodiment. The crystal 1 is a laser medium having nonlinear optical characteristics (for example, NYAB),
One surface has end surfaces A and B, and the other surface has diagonally cut end surfaces C and D. The semiconductor laser LD ₁ is an excitation light source, and its wavelength λ ₁ is, for example, 808 nm (N
YAB can be excited). The semiconductor laser LD ₂ is modulated by the signal source 2 and its emission wavelength is, for example, λ ₂ = 8
50 nm.

The excitation laser light from the semiconductor laser LD ₁ is focused by the lenses L ₁ and L ₂ and is incident on the crystal 1 from the end face B via the mirror M ₁ . Semiconductor laser LD ₂
The laser light modulated from the lens L _3, lens L ₄
In is focused, crystal 1 from the end surface A via a mirror M ₂
Is incident on. When the excitation laser beam of lambda ₁ = 808 nm in crystal body 1 is incident, the oscillation light is generated with a wavelength lambda _OSC = 1062 nm, the sum frequency mixing light during the oscillation light and the wavelength lambda ₂ of the modulated laser light ( λ _OUT = 472 nm).

Therefore, the mirror M ₁ transmits the wavelength λ ₁ and reflects all the wavelengths λ ₂ , λ _OSC and λ _OUT , and the mirror M ₂ transmits the wavelength λ ₂ and transmits the wavelengths λ ₁ and λ ₁ .
λ _OSC and λ _OUT are reflected. The end faces A, B, and D of the crystal 1 have wavelengths λ ₁ , λ ₂ , λ _OSC , λ
_OUT is totally reflected, and the end face C has a wavelength of λ.
_OUT is transmitted and wavelengths λ ₁ , λ ₂ , λ _OSC are reflected.

The above specific wavelength value is NYA
This is the case where the B crystal is used at θ = 40 °, and can be adjusted by phase matching as shown in FIG. According to this embodiment, output light (visible light) having a wavelength λ _OUT = 472 nm can be obtained, and its intensity can be modulated by the semiconductor laser LD ₂ .

FIG. 3 shows a semiconductor laser pumped laser of the second embodiment.
3 shows a light source. In this case, the mirror
M₁, Mirror M_TwoBy omitting the
It is trying to make it more compact. For this reason, the end faces A,
B is a convex curved surface, and the end surface A has a wavelength λ._TwoOn the end face B
The wavelength λ₁Can be transmitted. And the wavelength
λ _OSC, Λ_OUTAre reflected together.

In any of the above embodiments, the emitted light is a diverging beam and the optical path is oblique in any case. Therefore, as shown in FIG. 4A, if the convex lens 5 is installed near the end face C of the crystal 1, output light of a thin beam that goes straight can be obtained. If the prism 6 is provided as shown in FIG. 3B, the output light can travel straight.

FIG. 5 shows a semiconductor laser pumped coherent light source according to a third embodiment. In this case, the end faces C and D are common to the crystal body 1, and the end face E is used.
In this case, the end face E reflects the wavelengths λ ₁ , λ ₂ , λ _OSC and transmits the wavelength λ _OUT . According to this example, processing of the crystal 1 is easy.

FIG. 6 shows an example in which the semiconductor laser pumped coherent light source of the second embodiment is housed in a package. In FIG. 1A, a semiconductor body LD ₁ and lenses L ₁ and L ₂ are housed in a cylinder 11, and a semiconductor laser LD ₂ and lenses L ₃ and L ₄ are housed in a cylinder 12. Then, it is accommodated in the container 13 shown in FIG. The opening 1 of the container 13
5 is a terminal 1 of the semiconductor laser LD ₁ and the semiconductor laser LD ₂
The opening 17 is a light exit window.

[0016]

As described above, laser oscillation and sum frequency mixing are realized by a single crystal. And since the laser beam is incident from one surface of the crystal, the other surface of the crystal is used as a reflection end surface,
We are trying to make it more compact. Therefore, it is possible to provide a semiconductor laser-pumped coherent light source that has a high output and can be reduced in size, weight, and size.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a semiconductor laser pumped coherent light source according to a first embodiment.

FIG. 2 is a diagram showing a phase matching condition.

FIG. 3 is a configuration diagram of a semiconductor laser pumped coherent light source according to a second embodiment.

FIG. 4 is a diagram showing a modification of the second embodiment.

FIG. 5 is a configuration diagram of a semiconductor laser pumped coherent light source according to a third embodiment.

FIG. 6 is a diagram illustrating packaging of a semiconductor laser-pumped coherent light source according to a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Crystal body 2 ... Signal source LD ... Semiconductor laser M ... Mirror A, B, C, D, E ... End face

Claims (3)

(57) [Claims] 1. A crystal of a laser medium having non-linear optical characteristics, a first semiconductor laser light source for generating laser oscillation by entering an excitation laser beam from an end face on one side of the crystal, and the crystal A second semiconductor laser light source that receives modulated laser light from another end face on the one surface side of the body and generates sum frequency mixing with the laser oscillation light, and the other face of the crystal body A semiconductor laser-pumped coherent light source, characterized in that a side reflects the pump laser light and the modulated laser light and transmits the sum frequency mixed light. 2. The semiconductor laser-pumped coherent light source according to claim 1, wherein an optical component for converting an optical path of the emitted sum frequency mixed light is provided on the other surface side of the crystal. 3. A semiconductor laser-pumped coherent light source, wherein the semiconductor laser-pumped coherent light source according to claim 1 is packaged in a single container.