CN2136484Y

CN2136484Y - Blue and green beam splitting apparatus for argon ion laser

Info

Publication number: CN2136484Y
Application number: CN 92242515
Authority: CN
Inventors: 宋菲君; 俞蕾; 杨彦峰
Original assignee: CHINA DAHENG Co
Current assignee: CHINA DAHENG Co
Priority date: 1992-12-05
Filing date: 1992-12-05
Publication date: 1993-06-16
Anticipated expiration: 2002-12-05

Abstract

The utility model relates to a blue and green beam splitting apparatus for argon ion laser, belonging to a new design of the laser technique. The application of the optical rotatory dispersion effect of natural rotatory crystal make the polarization attitude of blue and green light in the incident linear polarized argon ion laser becomes orthogonal states. And the application of Wollaston prism changes blue and green light into space separation light beams. The utility model has the advantages of high beam-separating efficiency (low interference between channels), symmetric and compact structure and low cost, etc. The utility model is suitable for scientific research, teaching and the space separation of blue and green beams of the argon ion laser in an optical instrument.

Description

Blue and green beam splitting apparatus for argon ion laser

The utility model belongs to the laser application, and it is applicable to argon ion (A ⁺) blue light (wavelength is 488.0nm) of laser instrument institute radiation and the apart of green glow (wavelength is 514.0nm) two light beams.

Argon ion laser is known high power continuous wave gas laser, and purposes is very extensive.But general Argon ion laser is multiline output, and wherein principal ingredient is green glow (G) and blue light (B), and their power accounts for about 80% of whole output powers usually.In many application, these two spectral line light beams need be carried out apart.Known scheme has two kinds, and first kind of scheme utilized the effect of dispersion of prism, sees Fig. 1.Utilize difference blue, that green glow passes through the angle of deviation behind the prism, they are separated.The shortcoming of this scheme is to be difficult to constitute the optical system of symmetry; In addition, use the optical instrument structure complexity of this technology.Simultaneously, approaching because of two kinds of optical wavelength, they are very little by the angle of deviation difference behind the prism, must they could be separated through long distance.Second kind of scheme is plated film type spectroscope, sees Fig. 2.At the plane of incidence plating multilayer dielectric film of a glass substrate, it passes through green glow, blu-ray reflection.Design, process good spectroscope, green glow transmitance TG and blue light transmitance TB can accomplish

TG＝0.95，TB＝0.05

And the reflectivity RB of blue light and green glow reflectivity RG are respectively

RB＝1－TB＝0.95，RG＝1－TG＝0.05

The passage interference GT of transmitted light and catoptrical passage interference CR are defined as

CT＝TB／TG，

CR＝RG／RB，

Then CT=CR=5.2% does not still satisfy the application that the low passage of ask for something disturbs.

Task of the present utility model is, overcome complex structure in the apart technology of existing Argon ion laser medium blue, blue beam, the shortcoming of take up room big or passage interference higher (being that beam splitting efficient is not high enough), and the beam splitting mean of a kind of symmetry of design, compactness, it can realize the apart of Argon ion laser indigo plant, blue beam according to the rotatory dispersion effect, realizes the space beam splitting of high-level efficiency (low passage disturbs) with new technical characterictic.

Details are as follows in conjunction with the accompanying drawings to the technical scheme of this utility model and technical characterictic below:

Optical system of the present utility model is seen shown in Figure 3, and it 3 is gyrotropi crystals, for example quartzy (SiO ₂), tellurium dioxide (TeO ₂) etc., the optical axis of crystal is consistent with beam direction, and is vertical with plane of crystal.When the argon laser of linear polarization when optical axis of crystal direction is the crystal of d by thickness, the plane of oscillation of light beam will rotate because of the natural-optical rotation effect.If ((anglec of rotation of the plane of oscillation of wavelength X=514.5nm) is respectively ψ to blue light for wavelength X=488.0nm) and green glow _BAnd ψ _G, then have

ψ _B＝ρ _Bd，

ψ _G=ρ _Gd, ρ in the formula _BAnd ρ _GBe respectively the specific rotation (linearly polarized light passes through the vibration plane corner of unit length when optical axis is propagated in gyrotropi crystal) of blue light and green glow, ρ _B＞ρ _GCan get by following formula

△ψ＝ψ _B－ψ _G＝（ρ _B－ρ _G）d＝△ρd

△ ρ=ρ wherein _B-ρ _GIn following formula, make △ ψ=90 °, can solve d.After the argon ion laser beam of linear polarization was the crystal of d by thickness, the corner of the plane of oscillation of indigo plant, green glow was a quadrature.Settle an icelandspar wollaston prism in the crystal back, and make indigo plant, green glow be respectively e light (non-ordinary light) and the o light (ordinary light) of prism, then pass through prism after, blue, green glow separation is propagated to both direction with optical axis and roughly the same angle.

The beam splitting efficient of this scheme depends on two factors: (one). the extinction ratio of incoming laser beam (or degree of polarization); (2). the mismachining tolerance of crystal thickness d.Usually the extinction ratio of Argon ion laser is more than 200:1; The machining precision of crystal thickness can be done very highly, thereby beam splitting efficient can be done quite highly.

The visible Fig. 3 of embodiment of the present utility model.When crystal 3 is elected tellurium dioxide as, thickness d=3.10mm, the size of the size of the logical optical surface of crystal 3 and wollaston prism 4 logical optical surfaces depends on the size of light beam, 1.5-2 times of will get beam sizes (for example circular light beam diameter) usually.During cutting angle α=30 of wollaston prism 4 °, apart angle 2 θ of blue beam and blue beam=11 °.In order to reduce reflection loss, incident, the exit surface of crystal 3 and prism 4 all are coated with anti-reflection film.

Technical solution of the present utility model is that described argon laser indigo plant, edge light beam apart device are to be made of a gyrotropi crystal and wollaston prism.And make them become the light beam of apart.This device has characteristics such as high beam splitting efficient (low passage disturbs), structural symmetry, compactness, and cost is lower.Be applicable to the apart of argon laser indigo plant, blue beam in scientific research, teaching and the optical instrument, and wollaston prism is positioned at after the gyrotropi crystal.The favourable structure of this scheme also is: the optical axis of gyrotropi crystal and two logical optical surfaces are orthogonal.It is 90 ° in the difference of the corner by crystal after vibration plane that its thickness exactly makes in the argon laser along the indigo plant of same direction vibration, blue beam.The logical optical surface of wollaston prism is parallel with the logical optical surface of gyrotropi crystal.And wherein the plane of oscillation direction with the indigo plant that penetrates gyrotropi crystal, blue beam is consistent respectively for the optical axis direction of pair of orthogonal.

Fig. 1 is known a kind of dispersing prism beam splitting arrangement;

Fig. 2 is another kind of known plated film type beam splitting arrangement;

Fig. 3 is rotatory dispersion argon laser indigo plant described in the utility model, blue beam apart device.

Above-mentioned argon laser indigo plant, blue beam apart device, the performance that not only has high beam splitting efficient (low passage disturbs), and structure is very compact, make the system of symmetry easily, assemble, debug all simple and easy to do, cost is lower, can satisfy the request for utilization of most scientific researches, teaching and optical instrument.

Claims

1, a kind of novel argon laser indigo plant, blue beam light-dividing device is characterized in that being made of a gyrotropi crystal (3) and wollaston prism (4), and wollaston prism (4) is positioned at gyrotropi crystal (3) afterwards.

According to the described argon laser indigo plant of claim 1, blue beam light-dividing device, it is characterized in that 2, the optical axis of described gyrotropi crystal (3) and two logical optical surfaces are orthogonal.

3, according to the described argon laser indigo plant of claim 2, blue beam light-dividing device, it is characterized in that it is 90 ° in the difference of the corner by crystal after vibration plane that the thickness of gyrotropi crystal (3) exactly makes in the argon laser along the indigo plant of same direction vibration, blue beam.

4, according to any one described argon laser indigo plant, blue beam light-dividing device among the claim 1 to 3, it is characterized in that the logical optical surface of described wollaston prism (4) is parallel with the logical optical surface of gyrotropi crystal (3).

According to the described argon laser indigo plant of claim 4, blue beam light-dividing device, it is characterized in that 5, the plane of oscillation direction with the indigo plant that penetrates gyrotropi crystal (3), blue beam is consistent respectively for the optical axis direction of pair of orthogonal in the wollaston prism (4).