TWI529373B - Fiber Grating Tilt - Google Patents

Description

Fiber grating tilter

The invention relates to a fiber grating tilter, in particular to a fiber grating tilter which uses a mechanical method to cause a wavelength shift of an optical signal to achieve sensing purposes.

With the development of technology and the progress of the times, sensors that transmit signals by light are gradually gaining importance. Since the sensitivity of light to subtle changes is much higher than that of conventional electronic sensors, the use of optical fibers and fiber optic components for signal transmission or sensing has been the focus of research. However, in fiber optic components, the most commonly used sensors are non-fiber grating sensors.

Fiber gratings have been applied to tilt sensors. Many products have been developed and put into practical use. Although such tilt sensors have many advantages, such sensors use pendulums. More complex mechanical energy transfer elements, such as beams or pendulums, typically have to withstand unnecessary mechanical friction, rotation, and instability, thus increasing the probability of damage to the tilt sensor for stretched fiber gratings.

In view of the above-mentioned many problems, how to develop a non-stress-based fiber grating tilter to reduce the damage of the sensor itself to be easily stressed is a problem for the research and development personnel in the technical field of the present invention. Research.

The main object of the present invention is to provide a non-use mechanical tilter structure, To achieve the above-mentioned purpose, the present invention is a fiber grating tilter comprising a fiber grating and a container, wherein the fiber grating includes a first grating portion and a first fiber portion, one end of the first grating portion is connected to the first fiber portion, and the fiber grating is a periodically-graded fiber grating; and the container includes an accommodating space and a top portion, the top portion In the accommodating space, the two ends of the first grating portion are disposed on the top portion, and all or a portion of the first fiber portion extends outside the container, and an appropriate amount of liquid is injected into the accommodating space. The accommodating space is sealed, and the appropriate liquid system forms a bubble at the top of the accommodating space, and makes the bubble contact with the first grating portion at the top.

The present invention includes the following technical feature: the thickness of the first grating portion shell is smaller than the thickness of the first fiber portion shell.

The container is a cylinder, and the top is the inner wall of the cylinder.

The first grating portion is disposed on the top portion along the axial direction of the cylindrical container, and the fiber grating further includes a second fiber portion connected to the first grating portion relative to the first portion One end of a fiber portion, and all or one portion extends outside the container.

The fiber grating further includes a second grating portion, wherein the second grating portion is a periodically graded fiber grating, and the second grating portion is connected to the first grating portion, and the first grating is connected The second end of the second grating portion is disposed on the top portion, and the fiber grating further includes a second fiber portion connected to the second grating portion opposite to the first grating portion. And all or one portion extends outside the container, and the thickness of the second grating portion shell is smaller than the thickness of the first fiber portion shell.

The period of the first grating portion and the second grating portion are sequentially changed from a long period to a short period and a short period to a long period.

The periodic gradation relationship of the first grating portion and the second grating portion is sequentially from a short period to a long period, and a long period to a short period.

The shell of the first grating portion is etched or polished to make the shell thickness smaller than the thickness of the shell of the first fiber portion.

Another technical feature of the present invention includes: a fiber grating tilter comprising a fiber grating and a container, wherein: the fiber grating comprises a first grating portion, a first fiber portion and a second fiber portion. The two ends of the first grating portion are respectively connected to the first optical fiber portion and the second optical fiber portion, and the fiber grating is a long-period fiber grating; and the container includes an accommodating space and a top portion. The top portion is disposed in the accommodating space, the first grating portion is disposed on the top portion, and the first fiber portion and the second fiber portion are all or one portion extending outside the container, and are injected into the accommodating space. An appropriate amount of liquid seals the accommodating space, and the appropriate liquid system forms a bubble at the top of the accommodating space, and makes the bubble contact the grating portion at the top.

The container is a cylinder, and the top portion is an inner wall of the cylinder, and the grating portion is disposed on the top portion along the axial direction of the cylindrical container.

The shells of the first grating portion and the second grating portion are etched or polished to make the thickness of the shell smaller than the thickness of the shell of the first fiber portion.

The present invention achieves the desired object by the above-described structure, and the structure of the present invention will be further described in further detail below.

1‧‧‧ fiber grating

11‧‧‧First grating section

12‧‧‧First Fiber Division

13‧‧‧Second Fiber Division

14‧‧‧Second grating section

2‧‧‧ Container

21‧‧‧ accommodating space

22‧‧‧ top

23/23’‧‧‧ bubbles

3‧‧‧ Coupler

4‧‧‧Light source

5‧‧‧Spectrum Analyzer

W‧‧‧Liquid

P/P’‧‧·Crest

L1‧‧‧ horizontal line

L2‧‧‧ axis line

1 is a schematic perspective view of a first embodiment of the present invention.

Figure 2 is a perspective view of a three-dimensional structure of a first embodiment of the present invention.

Figure 3 is a cross-sectional view taken along the line A-A' of the first embodiment of the present invention.

4 is a schematic diagram of a test architecture of the present invention.

Figure 5 is a schematic view of the inclined state of the present invention.

Figure 6 is a partial cross-sectional view showing the tilting of the present invention.

Figure 7 is a schematic illustration of the wavelength of the optical spectrum analyzer of the present invention.

Figure 8 is a schematic illustration of the wavelength change of the spectrum analyzer of the present invention.

Figure 9 is a perspective view of a perspective structure of a second embodiment of the present invention.

In order to achieve the above object, please refer to FIG. 1 to FIG. 3, which is a first embodiment of the present invention. The present invention is a fiber grating tilter comprising a fiber grating (1) and a container (2), wherein: the fiber grating (1) comprising a first grating portion (11) and a first optical fiber portion (12), the first grating portion (11) having one end connected to the first optical fiber portion (12), and the optical fiber grating (1) is a periodically graded fiber grating, and the thickness of the first grating portion (11) is smaller than the thickness of the first fiber portion (12); and the container (2) includes an accommodation space (21) and a top portion (22), the top portion (22) is a wall surface of the accommodating space (21), and the two ends of the first grating portion (11) are disposed at the top portion (22), and the The first fiber portion (12) extends all or part of the container (2), and an appropriate amount of liquid (W) is injected into the accommodating space (21), and the accommodating space (21) is sealed. (W) is such that the top (22) of the accommodating space (21) forms a bubble (23) and causes the bubble (23) to be at the top (22). The first grating portion (11) is in contact with the cylinder, and the container (2) is a cylinder. The top portion (22) is an inner wall of the cylinder, and the first grating portion (11) is along the cylinder. The axial direction of the container is disposed on the top portion (22), and the fiber grating (1) further includes a second fiber portion (13), and the second fiber portion (13) is connected to the first grating portion (11) With respect to one end of the first fiber portion (12), all or a portion extends outside the container (2).

Moreover, the shell of the first grating portion (11) is etched or polished to make the shell thickness smaller than the thickness of the shell of the first fiber portion (12), so that the first grating portion (11) is more susceptible to The corresponding change occurs due to the influence of the bubble (23).

Please refer to FIG. 4 again, which is a test architecture diagram of a first embodiment of the present invention. The fiber grating tilter is connected to a light source (4) through a coupler (3), and is connected to a spectrum analyzer (5) at one end. After the light source (4) is output, it is transmitted to the first grating portion (11) via the coupler (3), and reflects a reflected light signal matched with the first grating portion (11) and passes through the coupler (3). And transmitted to the spectrum analyzer (5), and the spectrum analyzer (5) displays the change of the wavelength or wavelength of the optical signal.

Please refer to FIG. 5 to FIG. 8 at the same time, taking the periodic grading fiber grating as an example, and the sensing principle after being placed in the sensor is as follows: the periodic grading fiber grating waveform diagram has a wide wavelength range, and the present invention The thickness of the grating region of the grating of the periodically graded fiber grating is small. Therefore, when the grating region is placed in the liquid (W), the wavelength thereof is slightly shifted to the short wavelength. In the present embodiment, the total length of the grating region is 5 cm. After being placed in a liquid, the wavelength ranges from 1545 nm to 1555 nm, and when the grating region is exposed to the bubble, the wavelength returns to the original wavelength, that is, the wavelength shifts slightly longer wavelength, and at this time, the segment The wavelength of the light before the drift increases to generate a higher peak (P), please refer to Figures 5-6, when the axis of the fiber grating tilter of the present invention is inclined from the horizontal line L1 to the axis line In the case of L2, the inclination angle is θ, so that the bubble (23) moves, and the position of the grating portion that the bubble (23) contacts changes, thereby causing the wavelength to move, and the peak (P) moves accordingly, and therefore, in this embodiment In the example, when the bubble (23) moves by 1 mm, it will cause a wavelength shift of 1 mm*(1555nm-1545nm)/50mm=0.2nm, that is, when the original wavelength is 1545nm and the bubble shift (23) moves 1mm, then The wavelength of the peak (P') is 1545 nm + 0.2 nm = 1545.2 nm. In addition, the movement relationship of the bubble (23) caused by the oblique angle is tested as a linear relationship, for example, the inclination of 1 degree causes the bubble to move 1 cm, and therefore, when the original wavelength The wavelength after drifting at 1545 nm is 1546 nm, that is, drifting 1 nm, that is, the bubble moves 1/0.2=5 mm, and the angle is 5 degrees. The above description is based on the example. The relationship between the actual wavelength change and the angle still needs to be considered. The sensitivity of the sensor is determined.

Please refer to FIG. 5, which is a second embodiment of the present invention. The structure of this embodiment is substantially the same as that of the first embodiment, and the difference is as follows: The fiber grating (1) further includes a second grating portion (14), the second grating portion (14) is a periodically graded fiber grating, and the second grating portion (14) is coupled to the first grating portion ( 11) connected, and the two ends of the first grating portion (11) and the second grating portion (14) are disposed on the top portion (22), and the fiber grating (1) further includes a first a second fiber portion (13), the second fiber portion (13) is connected to one end of the second grating portion (14) relative to the first grating portion (11), and all or a portion extends to the container ( 2) the thickness of the second grating portion (14) is smaller than the thickness of the first optical fiber portion (12) or the second optical fiber portion (13), and the first grating portion (11) and the first portion The periodic gradient relationship of the two grating portions (14) is sequentially from a long period to a short period, a short period to a long period, or a short period to a long period, and a long period to a short period.

Moreover, the shells of the first grating portion (11) and the second grating portion (14) are etched or polished to make the thickness of the shell smaller than the thickness of the shell of the first fiber portion (12), so that the first The grating portion (11) and the second grating portion (14) are more susceptible to the influence of the bubble (23) and the corresponding change Chemical.

In the third embodiment of the present invention, the structure of the embodiment is substantially the same as that of the first embodiment, except that the fiber grating includes a first grating portion (11) and a first optical fiber portion (12). And a second fiber portion (13), the two ends of the first grating portion (11) are respectively connected to the first fiber portion (12) and the second fiber portion (13), and the fiber grating (1) is a long-period fiber grating, and the container (2) includes an accommodating space (21) and a top portion (22), the top portion (22) being attached to one of the wall spaces of the accommodating space (21) The first grating portion (11) is disposed on the top portion (22), and the first optical fiber portion (12) and the second optical fiber portion (13) are all or one portion extending outside the container (2).

In summary, the present invention can indeed measure the change of the angle of the environment, and can obtain the tilted angle from the wavelength drift relationship, so as to achieve the purpose of fabricating the fiber grating tilter in a mechanical manner, and therefore, The purpose of greatly extending the service life of the fiber grating tilter is achieved.

The above is only the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, that is, the variations, modifications, and modifications of the shapes, structures, features, and spirits described in the claims of the present invention. , should be included in the scope of the patent application of this creation.

1‧‧‧ fiber grating

11‧‧‧First grating section

12‧‧‧First Fiber Division

13‧‧‧Second Fiber Division

14‧‧‧Second grating section

2‧‧‧ Container

21‧‧‧ accommodating space

22‧‧‧ top

23‧‧‧ bubbles

W‧‧‧Liquid

Claims (11)

A fiber grating tilter comprising a fiber grating and a container, wherein: the fiber grating comprises a first grating portion and a first fiber portion, the first grating portion being connected to the first fiber portion at one end And the fiber grating is a periodically-graded fiber grating; and the container includes an accommodating space and a top portion, the top portion is disposed in the accommodating space, and the two ends of the first grating portion are disposed at the top portion And all or a portion of the first optical fiber portion extends outside the container, and an appropriate amount of liquid is injected into the accommodating space to seal the accommodating space, and the appropriate liquid system forms a bubble at the top of the accommodating space, and The bubble is in contact with the first grating portion at the top. The fiber grating tilter of claim 1, wherein the thickness of the first grating portion is smaller than the thickness of the first fiber portion. The fiber grating incliner of claim 2, wherein the container is a cylinder, the top portion being an inner wall of the cylinder. The fiber grating tilter of claim 3, wherein the first grating portion is disposed at the top portion along an axial direction of the cylindrical container, and the fiber grating further includes a second fiber portion, the second fiber portion is coupled The first grating portion is disposed at one end of the first optical fiber portion, and all or a portion extends outside the container. The fiber grating tilter of claim 2, wherein the fiber grating further comprises a second grating portion, wherein the second grating portion is a periodically graded fiber grating, and the second grating portion is connected to the first grating portion. And the two ends of the first grating portion and the second grating portion are disposed on the top, and the fiber grating further includes a second fiber portion, wherein the second fiber portion is connected to the second The grating portion is opposite to one end of the first grating portion, and all or a portion extends outside the container, the second The thickness of the grating portion of the grating portion is smaller than the thickness of the first optical fiber portion. The fiber grating tilter of claim 5, wherein the period of the first grating portion and the second grating portion are sequentially changed from a long period to a short period and a short period to a long period. The fiber grating tilter of claim 5, wherein the period of the first grating portion and the second grating portion are sequentially changed from a short period to a long period, and a long period to a short period. A fiber grating incliner comprising a fiber grating and a container, wherein: the fiber grating comprises a first grating portion, a first fiber portion and a second fiber portion, and the two ends of the first grating portion The fiber grating is a long-period fiber grating, and the fiber-optic grating is a long-period fiber grating; and the container includes an accommodating space and a top portion, the top portion is in the accommodating space The first grating portion is disposed at the top portion, and all or a portion of the first fiber portion and the second fiber portion extend outside the container, and an appropriate amount of liquid is injected into the accommodating space to seal the accommodating space. The liquid system forms a bubble at the top of the accommodating space and makes the bubble contact the grating portion at the top. The fiber grating incliner of claim 8, wherein the container is a cylinder, the top portion being an inner wall of the cylinder, the grating portion being disposed at the top portion along an axial direction of the cylindrical container. A fiber grating tilter according to claim 2 or 5, wherein the shell of the first grating portion is etched or polished to make the shell thickness smaller than the thickness of the shell of the first fiber portion. The fiber grating tilter of claim 5, wherein the first and second grating portions are etched or polished such that the thickness of the shell is smaller than the thickness of the shell of the first fiber portion.