This paper investigated the continuous measurement of a refractive index(RI)sensor based on macrobending microoptical plastic fiber(m-POF).The sensing properties of the RI sensor depend on the structure parameter,whic...This paper investigated the continuous measurement of a refractive index(RI)sensor based on macrobending microoptical plastic fiber(m-POF).The sensing properties of the RI sensor depend on the structure parameter,which is the ratio of macrobending radius of m-POF to the radius of fiber itself.The ratio changes with the measurement time increasing because of the water absorption,which introduces an maximum measurement deviation of 7.3×10^(-5) RIU when the immersion time exceeds 40 h.This work indicates that for the sensors based on POF,the measurement time must be taken into consideration for continuous measurement.展开更多
An optical code generating device has been developed based on a 1×2 asymmetric plastic optical fiber （POF） coupler. The code generating device provides a unique series of output power which are successively use...An optical code generating device has been developed based on a 1×2 asymmetric plastic optical fiber （POF） coupler. The code generating device provides a unique series of output power which are successively used as an optical code in a portable optical access-card system. The device utilizing a tap-off ratio （TOFR） technique based on a simple variation of the tap width of an asymmetric Y-branch splitter, allows various ratios of optical power to be generated. The POF coupler has been fabricated using low cost acrylic material and computer numerical control （CNC） machining technique. The simulated and fabricated results show the same linear characteristics between the TOFR and the tap width. The fabricated device enables a variation of the TOFR from 10% up to 50% for a tap width of 500 um to 1 mm.展开更多
The anti-radiation mechanism of polymeric plastic fiber is analyzed. The radiation characteristic of this type fiber is studied. Our experimental results indicate that under the low radiation dosage (below 1 kGy) the ...The anti-radiation mechanism of polymeric plastic fiber is analyzed. The radiation characteristic of this type fiber is studied. Our experimental results indicate that under the low radiation dosage (below 1 kGy) the plastic optical fiber’s transmission rate rises instead of descends while this type of fiber is radiated by γ ray, electron beam and proton beam respectively. After a period of time, it gradually reaches a constant value. But under the high radiation dosage (above 1 kGy) the fiber’s transmission rate descends after radiation. Later, it gradually goes up to a constant value.展开更多
The interfacial debonding in fiber-reinforced plastic(FRP)strengthened repair material will affect the bonding strength and lead to failure of the repair without warning.Unfortunately the interfacial damage is normall...The interfacial debonding in fiber-reinforced plastic(FRP)strengthened repair material will affect the bonding strength and lead to failure of the repair without warning.Unfortunately the interfacial damage is normally invisible and often in the form of a patch rather than a through-width crack.Therefore,a debonding patch detection technique based on fiber optic interferometry is proposed.A quasi-impulse loading is applied with a rubberhead hammer and the total elongation of a surface-mounted optical fiber along the length of the repair material is measured as a function of load position.When a debonding patch is present,the induced sudden slope or sign change on the plot of fiber integral strain v.s.load position will reveal the extent and the location of the debonded area.The results of the study indicate that the proposed technique is applicable for debonding patch detection in repaired members under various support conditions.展开更多
针对传统塑料光纤在传输过程中损耗大,使用长度较短的问题,提出在光纤连接部位制备一种新型共轭聚合物CN-PPV掺杂塑料光纤放大器材料,并对其制备工艺、荧光特性和增益特性进行研究。试验结果表明,在25 mL MMA、0.032 g BPO、20~75μL n...针对传统塑料光纤在传输过程中损耗大,使用长度较短的问题,提出在光纤连接部位制备一种新型共轭聚合物CN-PPV掺杂塑料光纤放大器材料,并对其制备工艺、荧光特性和增益特性进行研究。试验结果表明,在25 mL MMA、0.032 g BPO、20~75μL n-BM的工艺条件下制备的预制棒表面状态良好,内部无气泡出现,并在拉伸温度为150~177℃的条件下成功拉丝。塑料光纤最大发射截面为1.7×10^(-20) m^(2);当泵浦光传输距离增加,光谱出现明显红移现象,最大红移波长为12 nm。在光纤长度为50 cm的条件下,掺杂质量浓度为1 mg/L的光纤存在最大增益值,达到25 dB。而掺杂质量浓度为0.2 mg/L的光纤具备持续光放大能力,更适合作为光纤放大器的制备材料。展开更多
A corrugated surface long period grating(LPG)was fabricated on a flat-shaped plastic optical fiber(POF)as a refractive index(RI)sensor by a simple pressing with the heat pressure and mechanical die press print method....A corrugated surface long period grating(LPG)was fabricated on a flat-shaped plastic optical fiber(POF)as a refractive index(RI)sensor by a simple pressing with the heat pressure and mechanical die press print method.The light propagation characteristics of an LPG imprinted on a multi-mode POF were analyzed by the method of geometrical optics.Theoretical and experimental results showed that the structural parameters of the sensor affected the RI sensing performance,and the sensor with a thinner flat thickness,a deeper groove depth of the corrugated surface LPG,and a longer LPG exhibited better RI sensing performance.When the POF with a diameter of 1 mm was pressed with the heat pressure to a flat shape with a thickness of 600μm,an LPG with a period of 300μm,a groove depth of 200μm,and a length of 6 cm was fabricated on it,and the RI sensitivity of 1447%/RIU was obtained with a resolution of 5.494×10^(−6) RIU.In addition,the influences of the POF cladding,tilting of LPG,and bending of the sensing structure were investigated.The results demonstrated that after removing the cladding and tilting or bending the LPG,the RI sensing performance was improved.When the LPG imprinted on the flat-shaped POF was bent with a curvature radius of 6/πcm,the highest sensitivity of 6563%/RIU was achieved with a resolution of 2.487×10^(−9) RIU in the RI range of 1.3330–1.4230.The proposed sensor is a low-cost solution for RI measurement with the features of easy fabrication,high sensitivity,and intensity modulation at the visible wavelengths.展开更多
A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica fibers.After adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which ca...A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica fibers.After adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved ultimately.With the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000 μm).This new generation of POFs will find many applications.展开更多
An evanescent wave absorption （EWA） sensor based tapered plastic optical fiber （TPOF） coated with monolayer graphene film for ethanol molecules detection is demonstrated in this study. The continuous and monolayer...An evanescent wave absorption （EWA） sensor based tapered plastic optical fiber （TPOF） coated with monolayer graphene film for ethanol molecules detection is demonstrated in this study. The continuous and monolayer graphene films were grown on a Cu foil by using chemical vapor deposition （CVD） technology. Polymethyl methacrylate （PMMA） was used as the carrier to support the transfer of graphene from Cu foil to the skinless tapered optical fiber core. The accuracy of the TPOF sensor with graphene （G-TPOF sensor） is much higher than that without gra- phene （TPOF sensor）, which can be attributed to the molecules enriched on the surface of graphene. The absorbance （A） and the concentrations of ethanol solution show an excellent proportional relationship in a range of 0--100%. The dynamic response of the G-TPOF sensor has shown strong reversibility, repeatability and stability at room temperature. The response time and recovery time of the G-TPOF sensor for different concentrations are all less than 30 s. Beyond that, we selected the Chinese liquor as the analyte, and the results are consistent with the concen- tration-list obtained in the experiment.展开更多
A dissolved oxygen （DO） sensor based on U-shape plastic optical fiber （POF） and dichlorotris （1, 10- phenanthroline） ruthenium （[Ru（dpp）^3]^2＋） as an oxygen indicator was described. Fluorescence intensity a...A dissolved oxygen （DO） sensor based on U-shape plastic optical fiber （POF） and dichlorotris （1, 10- phenanthroline） ruthenium （[Ru（dpp）^3]^2＋） as an oxygen indicator was described. Fluorescence intensity and lifetime were measured when the sensor was soaked into a water bath blasted with air with varied O2/N2 ratios. The influence of Ru concentration, annealing time and U-shaped POF curve radius on the system sensitivity was also studied. A two-layer model was proposed to analyze the deviation from linear relation described by Stern-Volmer equation, and to explain the deviation and the dependence of the fluorescence on curvature of U-shape POF. By fitting the experimentally measured sub-linear relation of τ0/τ ratio versus oxygen concentration, the proportion of effectively sensitive layer and the Stern-Volmer coefficient can be evaluated to be f = 0.59 and Ksv = 0.61 typically.展开更多
基金National Natural Science Foundation of China(No.61405127)Key Program for International S&T Cooperation Projects of China(No.2013DFR10150)
文摘This paper investigated the continuous measurement of a refractive index(RI)sensor based on macrobending microoptical plastic fiber(m-POF).The sensing properties of the RI sensor depend on the structure parameter,which is the ratio of macrobending radius of m-POF to the radius of fiber itself.The ratio changes with the measurement time increasing because of the water absorption,which introduces an maximum measurement deviation of 7.3×10^(-5) RIU when the immersion time exceeds 40 h.This work indicates that for the sensors based on POF,the measurement time must be taken into consideration for continuous measurement.
基金supported by the Malaysian E-Science Fund under Grant No 01-01-01-SF0197
文摘An optical code generating device has been developed based on a 1×2 asymmetric plastic optical fiber （POF） coupler. The code generating device provides a unique series of output power which are successively used as an optical code in a portable optical access-card system. The device utilizing a tap-off ratio （TOFR） technique based on a simple variation of the tap width of an asymmetric Y-branch splitter, allows various ratios of optical power to be generated. The POF coupler has been fabricated using low cost acrylic material and computer numerical control （CNC） machining technique. The simulated and fabricated results show the same linear characteristics between the TOFR and the tap width. The fabricated device enables a variation of the TOFR from 10% up to 50% for a tap width of 500 um to 1 mm.
文摘The anti-radiation mechanism of polymeric plastic fiber is analyzed. The radiation characteristic of this type fiber is studied. Our experimental results indicate that under the low radiation dosage (below 1 kGy) the plastic optical fiber’s transmission rate rises instead of descends while this type of fiber is radiated by γ ray, electron beam and proton beam respectively. After a period of time, it gradually reaches a constant value. But under the high radiation dosage (above 1 kGy) the fiber’s transmission rate descends after radiation. Later, it gradually goes up to a constant value.
基金supported by the National Natural Science Foundation of China(No.51278156)the Basic Project of Shenzhen Science & Technology Program(No.JCYJ2017030155815876)
文摘The interfacial debonding in fiber-reinforced plastic(FRP)strengthened repair material will affect the bonding strength and lead to failure of the repair without warning.Unfortunately the interfacial damage is normally invisible and often in the form of a patch rather than a through-width crack.Therefore,a debonding patch detection technique based on fiber optic interferometry is proposed.A quasi-impulse loading is applied with a rubberhead hammer and the total elongation of a surface-mounted optical fiber along the length of the repair material is measured as a function of load position.When a debonding patch is present,the induced sudden slope or sign change on the plot of fiber integral strain v.s.load position will reveal the extent and the location of the debonded area.The results of the study indicate that the proposed technique is applicable for debonding patch detection in repaired members under various support conditions.
文摘A corrugated surface long period grating(LPG)was fabricated on a flat-shaped plastic optical fiber(POF)as a refractive index(RI)sensor by a simple pressing with the heat pressure and mechanical die press print method.The light propagation characteristics of an LPG imprinted on a multi-mode POF were analyzed by the method of geometrical optics.Theoretical and experimental results showed that the structural parameters of the sensor affected the RI sensing performance,and the sensor with a thinner flat thickness,a deeper groove depth of the corrugated surface LPG,and a longer LPG exhibited better RI sensing performance.When the POF with a diameter of 1 mm was pressed with the heat pressure to a flat shape with a thickness of 600μm,an LPG with a period of 300μm,a groove depth of 200μm,and a length of 6 cm was fabricated on it,and the RI sensitivity of 1447%/RIU was obtained with a resolution of 5.494×10^(−6) RIU.In addition,the influences of the POF cladding,tilting of LPG,and bending of the sensing structure were investigated.The results demonstrated that after removing the cladding and tilting or bending the LPG,the RI sensing performance was improved.When the LPG imprinted on the flat-shaped POF was bent with a curvature radius of 6/πcm,the highest sensitivity of 6563%/RIU was achieved with a resolution of 2.487×10^(−9) RIU in the RI range of 1.3330–1.4230.The proposed sensor is a low-cost solution for RI measurement with the features of easy fabrication,high sensitivity,and intensity modulation at the visible wavelengths.
基金the National Natural Science Foundation of China(Grant Nos.60444003,60577009)
文摘A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica fibers.After adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved ultimately.With the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000 μm).This new generation of POFs will find many applications.
基金The authors are grateful for financial support from the National Natural Science Foundation of China （Nos. 61205174, 61401258, 11504209, and 11404195）, Excellent Young Scholars Research Fund of Shandong Normal University, and Shandong Province Natural Science Foundation （No. ZR2013EMM009）.
文摘An evanescent wave absorption （EWA） sensor based tapered plastic optical fiber （TPOF） coated with monolayer graphene film for ethanol molecules detection is demonstrated in this study. The continuous and monolayer graphene films were grown on a Cu foil by using chemical vapor deposition （CVD） technology. Polymethyl methacrylate （PMMA） was used as the carrier to support the transfer of graphene from Cu foil to the skinless tapered optical fiber core. The accuracy of the TPOF sensor with graphene （G-TPOF sensor） is much higher than that without gra- phene （TPOF sensor）, which can be attributed to the molecules enriched on the surface of graphene. The absorbance （A） and the concentrations of ethanol solution show an excellent proportional relationship in a range of 0--100%. The dynamic response of the G-TPOF sensor has shown strong reversibility, repeatability and stability at room temperature. The response time and recovery time of the G-TPOF sensor for different concentrations are all less than 30 s. Beyond that, we selected the Chinese liquor as the analyte, and the results are consistent with the concen- tration-list obtained in the experiment.
基金the Foundation of Shanghai Technology Committee under Grant No.061458037
文摘A dissolved oxygen （DO） sensor based on U-shape plastic optical fiber （POF） and dichlorotris （1, 10- phenanthroline） ruthenium （[Ru（dpp）^3]^2＋） as an oxygen indicator was described. Fluorescence intensity and lifetime were measured when the sensor was soaked into a water bath blasted with air with varied O2/N2 ratios. The influence of Ru concentration, annealing time and U-shaped POF curve radius on the system sensitivity was also studied. A two-layer model was proposed to analyze the deviation from linear relation described by Stern-Volmer equation, and to explain the deviation and the dependence of the fluorescence on curvature of U-shape POF. By fitting the experimentally measured sub-linear relation of τ0/τ ratio versus oxygen concentration, the proportion of effectively sensitive layer and the Stern-Volmer coefficient can be evaluated to be f = 0.59 and Ksv = 0.61 typically.
