The online optical-fiber laser isolator of a kind of compact reflection-type
Technical field
The utility model is applicable to fiber laser field, particularly the online optical-fiber laser isolator of a kind of compact reflection-type.
Background technology
Because fiber laser technology is to reflected light quite sensitive, if the luminous energy returned in system is stronger, the performance of whole system then may be caused sharply to decline, even whole system is burnt, so need the spacer assembly increasing light path in the optical path, filter out as much as possible for this part back light, to avoid it on the impact of laser system, improve the stability that system exports.
Existing high power collimation output type isolator as shown in Figure 2, comprises high power collimating apparatus 201, first beam splitter 202, Faraday polarization apparatus 203, magnetic ring component 204,22.5 degree of 1/2nd wave plate 205, second beam splitter 206 and reception collimating apparatus 207 from front to back along the transmission direction of light forward and forms.Light is by after collimating apparatus 201 outgoing, through the first beam splitter 202, be divided into polarization state orthogonal two-beam O, E, two-beam is after Faraday polarization apparatus, polarization state clockwise 45 degree respectively (sense of rotation can according to design alternative), then after 22.5 degree of 1/2nd wave plate, two polarization states become the two independent polarization states with outgoing O, E polarization state vertical (or parallel), after the second beam splitter, merge into light beam and output to reception collimating apparatus.
Its reverse optical path is as described below, back light is after outgoing receives collimating apparatus, through the second beam splitter 206, be divided into O, E two-beam, after 22.5 degree of 1/2nd wave plate, the polarization state of two-beam rotates 45 degree, again through Faraday polarization apparatus, because Faraday polarization apparatus is non-reciprocal device, its polarization state still rotates in the direction of the clock, therefore the polarization state of two-beam is through afterwards, gone back by rotation again in its polarization direction, at this moment, concerning the first beam splitter, O light is above still O light, by linear transmission, below be E light, then be deflected, two-way light all can not turn back in incident collimating apparatus.
Above-mentioned isolator is owing to employing linear pattern light path, and all devices all only through once, do not reach optimum and use, so device volume greatly, cost is high, and competitive power is low.
Summary of the invention
The purpose of this utility model is to provide a kind of compact reflection-type online optical-fiber laser isolator.
For achieving the above object, the technical solution of the utility model is: the online optical-fiber laser isolator of a kind of compact reflection-type, comprise, along the twin-core high power collimating apparatus that light forward path sets gradually, roof prism, beam splitter, Faraday polarization apparatus and realization, polarisation of light state is rotated 22.5 degree of 1/2nd wave plate of 45 degree, also comprise for the magnetic ring component to Faraday polarization apparatus applying external magnetic field.
In the utility model embodiment, the forward optic path process of the online optical-fiber laser isolator of described compact reflection-type is: become collimated light from the incident light of Optical Fiber Transmission through a wherein core incidence of twin-core high power collimating apparatus, via roof prism, this collimated light is reflected, beam splitter is transferred to after deflection angle, be beamed into O, E two-beam, again via Faraday polarization apparatus by this O, the polarization state of E two-beam is clockwise or be rotated counterclockwise 45 degree, and reflex to 22.5 degree of 1/2nd wave plate by the polarization state of two-beam counterclockwise or turn clockwise 45 degree, the polarization state of this two-beam is made to get back to former polarization state, then this two-beam reflected synthesizes light beam via beam splitter, and after entering roof prism refraction, transfer to twin-core high power collimating apparatus, and via another core outgoing of twin-core high power collimating apparatus to another optical fiber.
In the utility model embodiment, the priority position interchangeable of described Faraday polarization apparatus and 22.5 degree of 1/2nd wave plate, namely during the transmission of light forward, after beam splitter outgoing, first through 22.5 degree of 1/2nd wave plate, then through Faraday polarization apparatus.
In the utility model embodiment, the optical axis angle of described beam splitter is 45 degree, the function that the beam splitting realizing light is restrainted with conjunction; This beam splitter is made by YVO4.
In the utility model embodiment, described 22.5 degree of 1/2nd wave plate is made by quartz crystal.
In the utility model embodiment, the side that described Faraday polarization apparatus enters at light forward is coated with anti-reflection film, and opposite side is coated with high-reflecting film.
Compared to prior art, the utility model has following beneficial effect:
1, the function that two optical fiber high power collimating apparatus realizes existing design two collimating apparatuss is employed;
2, only employ a beam splitter, there is not the problem of existing two beam splitter pairings in process of production, simultaneously cost savings half;
3, Faraday polarization apparatus is coated with high-reflecting film, only needs the length of existing design half can realize former function, and because size reduces, cost also can only have the half of existing design;
4, because device only has a half-size scale of existing design, so the apparent size of product is greatly reduced in diameter.
Accompanying drawing explanation
Fig. 1 is the top view of the compact online optical-fiber laser spacer structures of reflection-type of the utility model.
Fig. 2 be existing isolator lose road and structural representation.
Fig. 3 A is Fig. 1 side-looking state, and utility model forward of the present invention is transferred to high-reflecting film light path schematic diagram.
Fig. 3 B is Fig. 1 side-looking state, and utility model high-reflecting film of the present invention is to collimating apparatus forward transmission light path schematic diagram.
Fig. 4 A is Fig. 1 side-looking state, and utility model reverse transfer of the present invention is to high-reflecting film light path schematic diagram.
Fig. 4 B is Fig. 1 side-looking state, and utility model high-reflecting film of the present invention is to collimating apparatus reverse transfer light path schematic diagram.
101,301,401-twin-core high power collimating apparatus in figure:, 102,302,402-roof prism, 103,202,206,303,403-beam splitter, 104,205,304,404-22.5 degree 1/2nd wave plate, 105,203,305,405-Faraday polarization apparatus, 106,204,306,406-magnetic ring component, 201-high power collimating apparatus, 207 receive collimating apparatuss.
Embodiment
Below in conjunction with accompanying drawing, the technical solution of the utility model is specifically described.
As shown in Figure 1, the online optical-fiber laser isolator of a kind of compact reflection-type of the present utility model, comprise along the twin-core high power collimating apparatus 101 that light forward path sets gradually, roof prism 102, beam splitter 103, Faraday polarization apparatus 105 and realize, by 22.5 degree of 1/2nd wave plate 104 of polarisation of light state rotation 45 degree, also comprising the magnetic ring component 106 for applying external magnetic field to Faraday polarization apparatus 105.
The forward optic path process of the online optical-fiber laser isolator of described compact reflection-type is: become collimated light from the incident light of Optical Fiber Transmission through a wherein core incidence of twin-core high power collimating apparatus, via roof prism, this collimated light is reflected, beam splitter is transferred to after deflection angle, be beamed into O, E two-beam, again via Faraday polarization apparatus by this O, the polarization state of E two-beam is clockwise or be rotated counterclockwise 45 degree, and reflex to 22.5 degree of 1/2nd wave plate by the polarization state of two-beam counterclockwise or turn clockwise 45 degree, the polarization state of this two-beam is made to get back to former polarization state, then this two-beam reflected synthesizes light beam via beam splitter, and after entering roof prism refraction, transfer to twin-core high power collimating apparatus, and via another core outgoing of twin-core high power collimating apparatus to another optical fiber.The priority position interchangeable of described Faraday polarization apparatus and 22.5 degree of 1/2nd wave plate, namely during the transmission of light forward, after beam splitter outgoing, first through 22.5 degree of 1/2nd wave plate, then through Faraday polarization apparatus.
Below by way of specific embodiments, the online fibre optic isolater of reflection-type of the present invention is further described:
1, as shown in schematic diagram 1, the output light of laser instrument becomes collimated light after twin-core high power collimating apparatus 101, owing to being twin-core high power collimating apparatus, its fiber core is off center certain distance, so the emergent light of two optical fiber is all with angle outgoing, and the angle of two-beam and device center axle is symmetrical, the size of angle is directly related with fibre core offset distance and Lens Design, and project planner can easily calculate its size;
2, emergent light is after roof prism 102, owing to being reflected by roof prism 102, again changes angle, needs carefully to calculate during this prism design, makes emergent light and roof prism physical axis intersection point just be positioned at the position of Faraday polarization apparatus 105 high-reflecting film;
3, after roof prism 102, put beam splitter 103, the material usually making beam splitter is YVO4, and its optical axis angle is 45 degree, can realize the spectroscopic distance of 10:1 like this, and namely O, E two-beam can be separated the gap of about 1mm by the crystal length of 10mm; (as shown in Figure 3A for being divided into O, E two-beam through beam splitter 103)
4, after beam splitter 103, light enters into Faraday polarization apparatus 105, and it is one-sided is coated with high-reflecting film, and opposite side is coated with anti-reflection film, light is rotated 22.5 degree by under the incident single pass case in anti-reflection film side by light, the sense of rotation of light is only relevant with magnetic direction, so can determine according to design to left-handed or dextrorotation, here by explanation clockwise, after high-reflecting film reflection, again through Faraday polarization apparatus 105, its polarization state, again by rotation 22.5 degree, realizes overall 45 degree turn clockwise;
5, two bundle polarization states are by the polarized light that rotates 45 degree after through optical axis angle being 1/2nd wave plates of 22.5 degree, and polarization state is rotated 45 degree, and the effect of Faraday polarization apparatus 105 offset, two polarization states get back to former polarization state again;
6, two orthogonal polarization states are after beam splitter 103, are again synthesized light beam; (as shown in Figure 3 B)
7, after synthesizing a branch of light outgoing beam splitter 103, enter roof prism 102, because roof prism 102 is monosymmetric, therefore after roof prism 102, the drift angle of light is lucky and incident angle is symmetrical;
8, be coupled in another root optical fiber after twin-core high power collimating apparatus 101 is coupled with the light of incident angle symmetry, so far complete forward optic path.
9, product reverse transfer light path can see schematic diagram 4A and 4B, device reverse transfer then receives optical fiber and enters light, according to the reversible principle of light path, before light enters Faraday polarization apparatus 405, its upper and lower two optical path states are consistent with forward, and namely polarization state is 45 degree of heeling conditions;
10, because Faraday polarization apparatus 405 is non-reciprocal device, then light is by polarization state still turns clockwise 45 degree by it afterwards, then at this moment, it is orthogonal that the polarization state of outgoing Faraday polarization apparatus compares incident polarization state;
11, due to the change of polarization state, then at this moment for beam splitter 403, former polarization state is E light state, is now O light, then transmits along former direction; Former polarization state is O light state, is now E light, be then split the cheap certain distance of device, therefore after beam splitter, two-beam is separated, and all can not get back to former outgoing collimating apparatus 401, light path is intercepted by perfection.
Advantage of the present utility model is:
1. employ two optical fiber high power collimating apparatus, have output and receiving function concurrently, realize the function of existing design two collimating apparatuss;
2. roof prism is employed, the output of deflection collimating apparatus and reception light;
3. only employ a beam splitter, have beam splitting concurrently and close the function of restraint, there is not the problem of existing two beam splitter pairings in process of production, while cost savings half;
4. Faraday polarization apparatus is coated with high-reflecting film, only needs the length of existing design half can realize former function, and because size reduces, cost also can only have the half of existing design;
5. because device only has a half-size scale of existing design, so the apparent size of product is greatly reduced in diameter.
Although the foregoing describe embodiment of the present utility model; but be familiar with those skilled in the art to be to be understood that; specific embodiment described by us is illustrative; instead of for the restriction to scope of the present utility model; those of ordinary skill in the art, in the modification of the equivalence done according to spirit of the present utility model and change, should be encompassed in scope that claim of the present utility model protects.