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- Hammarling, Krister, 1968-, et al.
(författare)
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Blood pH optrode based on evanescent waves and refractive index change
- 2014
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Ingår i: Progress in Biomedical Optics and Imaging - Proceedings of SPIE. - : SPIE. - 9780819498519 ; , s. Art. no. 89381F-
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Konferensbidrag (refereegranskat)abstract
- Sensing pH in blood with an silica multimode optical fiber. This sensor is based on evanescent wave absorption and measures the change of the refractive index and absorption in a cladding made of a biocompatible Polymer. In contrast to many existing fiber optical sensors which are based upon different dyes or florescent material to sense the pH, here presents a solution where a part of the cladding is replaced with a Poly (β-amino ester) made of 1.4-Butanediol diacrylate, Piperazine, and Trimethylolpropane Triacrylate. Piperazine has the feature of changing its volume by swelling or shrinking in response to the pH level. This paper utilizes this dimension effect and measure the refractive index and the absorption of the cladding in respect to different pH-levels. The alteration of refractive index also causes a change in the absorption and therefore the output power changes as a function of the pH level. The sensor is sensitive to pH in a wide spectral range and light absorbency can be observed for wavelengths ranging from UV to far IR. © 2014 SPIE.
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| 2. |
- Hammarling, Krister, 1968-, et al.
(författare)
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Fiber Bragg Grating filter using Evaporated Induced Self Assembly of silica nano particles
- 2014
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Ingår i: Proceedings of SPIE - The International Society for Optical Engineering. - : SPIE. ; , s. Art. no. 898225-
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Konferensbidrag (refereegranskat)abstract
- In the present work we conduct a study of ber lters produced by evaporation of silica particles upon aMM-ber core. A band lter was designed and theoretically veried using a 2D Comsol simulation model ofa 3D problem, and calculated in the frequency domain in respect to refractive index. The ber lters werefabricated by stripping and chemically etching the middle part of an MM-ber until the core was exposed. Amono layer of silica nano particles were evaporated on the core using an Evaporation Induced Self-Assembly(EISA) method. The experimental results indicated a broader bandwidth than indicated by the simulationswhich can be explained by the mismatch in the particle size distributions, uneven particle packing and nallyby eects from multiple mode angles. Thus, there are several closely connected Bragg wavelengths that buildup the broader bandwidth. The experimental part shows that it is possible by narrowing the particle sizedistributing and better control of the particle packing, the lter eectiveness can be greatly improved.
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