A kind of many taper holes warp architecture plastic optical fiber sensor
Technical field
The invention belongs to the technical field of Fibre Optical Sensor, particularly relate to a kind of plastic optical fiber sensor of many taper holes warp architecture.
Background technology
Based on fibre-optical bending, realize the structure of physical quantity to external world and mainly contain at present: directly bending, fiber grating and various interference structures etc.Although above structure all has sensitivity characteristic for bending, all there is inherent defect or deficiency in these structures: the direct bending frangibility of glass optical fiber; The direct bend-insensitive of plastic optical fiber; The manufacture craft of various gratings and interference structure requires high, and difficulty of processing is large, and measuring system cost is very high.
Plastic optical fiber light weight, softness, more resistance to destruction (vibration and bending).Plastic optical fiber has excellent pulling strengrth, durability and the little feature that takes up room.In addition, the junction loss of plastic optical fiber is little, is easy to processing.Above feature makes plastic optical fiber be with a wide range of applications at sensory field, but common plastics optical fiber is extremely insensitive for bending, makes to utilize the bending loss of plastic optical fiber to realize very difficulty of high-precision sensor measuring.Therefore the plastic optical fiber structure that, development has a bending sensitivity characteristic is significant.
Summary of the invention
The technical problem to be solved in the present invention is, overcomes common plastics optical fiber and cannot utilize bending loss characteristics to realize the shortcoming of high-precision sensing, and a kind of many taper holes plastic optical fiber warp architecture with bending sensitivity characteristic is provided.
Above-mentioned technical matters realizes by following technical scheme:
A kind of many taper holes warp architecture plastic optical fiber sensor, it is characterized in that, on the plastic optical fiber with arc-shaped bend structure, be arranged with conical micropore, the conical axis of micropore and the central shaft of optical fiber intersect vertically, all conical micropore Zhui Di center is on the same bus of optical fiber, and the bus at place, Qie Zhuidi center is in the outside of the arc of described arc-shaped bend structure.
Described plastic optical fiber can be various standard-sized step multimode plastic optical fibers.
Preferably 10 microns~500 microns of the cone bottom diameters of described conical micropore; Preferably 0.5 millimeter~1 millimeter of center distance at the bottom of the cone of adjacent conical micropore.
When the quantity of described tapered micro holes is more than or equal to 10, experiment shows better effects if.
Beneficial effect:
Many taper holes of the present invention warp architecture plastic optical fiber sensor, has simple in structurely, with low cost, highly sensitive, and the advantage such as be swift in response.The invention enables the high-precision sensing measurement based on plastic optical fiber bending loss mechanism to be achieved.
Brief description of the drawings
Fig. 1 is the schematic side view of many taper holes of the present invention warp architecture plastic optical fiber sensor.
Fig. 2 is the schematic top plan view of many taper holes of the present invention warp architecture plastic optical fiber sensor.
Fig. 3 is bellmouth schematic diagram of the present invention.
Fig. 4 is the bending loss experimental provision schematic diagram used that the embodiment of the present invention is tested many taper holes plastic optical fiber and ordinary optic fibre.
Fig. 5 is many taper holes plastic optical fiber of recording in the embodiment of the present invention and the bending loss figure of ordinary optic fibre.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further illustrated.
Embodiment 1
Optical fiber used is the step multimodal polymer optical fiber that MIT produces, and concrete model is ESKA-CK40, and the overall diameter of optical fiber is 1.00mm, and core diameter is 0.96mm, and fibre core is made up of polymethylmethacrylate, and fiber core refractive index is 1.492; Cladding thickness is 0.02mm, and covering is made up of fluororesin, and cladding index is 1.417; Numerical aperture NA=0.467, loss is 200dB/km, the normal working temperature of optical fiber is-55 DEG C-70 DEG C.
Utilize 800nm femtosecond laser on above-mentioned plastic optical fiber, to get 13 bellmouths, each bellmouth axis is parallel, and all intersect vertically with optical fiber axis, the axial line distance in adjacent conical hole is 0.5mm, cone bottom diameter 150um, all on the same bus of optical fiber, cone point does not penetrate the covering of optical fiber opposite side at the cone end, produces the plastic optical fiber of 13 taper holes; Again the perforated zone of plastic optical fiber is wound around and bends to arc, and make the cone bottom of conical micropore in the outside of arc.
As Fig. 4, beat bellmouth plastic optical fiber and be connected with photodetector with light source respectively by coupling mechanism, be less than 0.5dB through measuring coupling device plug loss.The taper porose area of plastic optical fiber is wrapped on cylinder, changes cylindrical radius to change the flexibility of bellmouth plastic optical fiber, record data computed losses, with the situation of change of bending radius, the results are shown in Figure 5.
Embodiment 2
On the basis of embodiment 1, change bellmouth distance between axles into 1.0mm, other parameter constant, test loss, with the situation of change of bending radius, the results are shown in Figure 5.
Embodiment 3
On the basis of embodiment 1, change bellmouth quantity into 20, other parameter constant, test loss, with the situation of change of bending radius, the results are shown in Figure 5.
Embodiment 4
On the basis of embodiment 2, change bellmouth quantity into 20, other parameter constant, test loss, with the situation of change of bending radius, the results are shown in Figure 5.
Embodiment 5
Select a plastic optical fiber that parameter is identical with embodiment 1, but do not punch, test the situation of change of loss with bending radius by the method for testing of embodiment 1, the results are shown in Figure 5.
Comparative example 1~5, and visible common plastics optical fiber is extremely insensitive for bending, and the warp architecture of many taper holes plastic optical fiber is very responsive for bending.From experimental example, in the time that bending radius changes to 0.6cm from 7.5cm, the common plastics fibre loss of punching has not changed about 2dB, and the loss of many bellmouths plastic optical fiber has changed nearly 20dB, the loss of visible many taper holes of the present invention warp architecture plastic optical fiber sensor is very responsive to the variation of bending radius, and the quantity in hole is more, and effect is more obvious.Can measure the various physical quantitys that can cause bending radius of the present invention to change according to the loss characteristic of plastic optical fiber, as quality, pressure, temperature etc.