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Study of the effect of distance and misalignment between magnetically coupled coils for wireless power transfer in intraocular pressure measurement.

Rendon-Nava AE, Díaz-Méndez JA, Nino-de-Rivera L, Calleja-Arriaga W, Gil-Carrasco F, Díaz-Alonso D - ScientificWorldJournal (2014)

Bottom Line: Power transfer was done by magnetic induction coupling method, by placing one of the inductors of the Maxwell-Wien bridge circuit and the inductor of the implant in close proximity.The Maxwell-Wien bridge circuit was biased with a 10 MHz sinusoidal signal.In order to have a proper inductive coupling link, special care must be taken when placing the two coils in proximity to avoid misalignment between them.

View Article: PubMed Central - PubMed

Affiliation: Graduate Department, National Polytechnic Institute of Mexico (IPN), ESIME UPC, Avenida Santa Ana 1000, San Francisco Culhuacan, 04260 Mexico City, DF, Mexico.

ABSTRACT
An analysis of the effect of distance and alignment between two magnetically coupled coils for wireless power transfer in intraocular pressure measurement is presented. For measurement purposes, a system was fabricated consisting of an external device, which is a Maxwell-Wien bridge circuit variation, in charge of transferring energy to a biomedical implant and reading data from it. The biomedical implant is an RLC tank circuit, encapsulated by a polyimide coating. Power transfer was done by magnetic induction coupling method, by placing one of the inductors of the Maxwell-Wien bridge circuit and the inductor of the implant in close proximity. The Maxwell-Wien bridge circuit was biased with a 10 MHz sinusoidal signal. The analysis presented in this paper proves that wireless transmission of power for intraocular pressure measurement is feasible with the measurement system proposed. In order to have a proper inductive coupling link, special care must be taken when placing the two coils in proximity to avoid misalignment between them.

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Structure of MEMS touch mode capacitive pressure sensor.
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Related In: Results  -  Collection


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fig2: Structure of MEMS touch mode capacitive pressure sensor.

Mentions: The IOP sensor will be a MEMS touch mode capacitive pressure sensor (MEMS TMCPS). The basic element of a TMCPS is an equivalent parallel plate capacitor with clamped edges [17] as shown in Figure 2. The capacitance C is represented as(1)C=εAd,where ε is the permittivity of the dielectric thin film, A is a touching area of diaphragm, and d is the gap space between the two electrodes. The upper plate of the capacitor, known as the diaphragm, will deform in response to an applied pressure and finally will come into contact with the dielectric thin film. Since the permittivity and the thickness are constant values, the capacitance C will only depend on the touching area A. Consequently we can measure the applied pressure to the diaphragm by reading the capacitance.


Study of the effect of distance and misalignment between magnetically coupled coils for wireless power transfer in intraocular pressure measurement.

Rendon-Nava AE, Díaz-Méndez JA, Nino-de-Rivera L, Calleja-Arriaga W, Gil-Carrasco F, Díaz-Alonso D - ScientificWorldJournal (2014)

Structure of MEMS touch mode capacitive pressure sensor.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4109074&req=5

fig2: Structure of MEMS touch mode capacitive pressure sensor.
Mentions: The IOP sensor will be a MEMS touch mode capacitive pressure sensor (MEMS TMCPS). The basic element of a TMCPS is an equivalent parallel plate capacitor with clamped edges [17] as shown in Figure 2. The capacitance C is represented as(1)C=εAd,where ε is the permittivity of the dielectric thin film, A is a touching area of diaphragm, and d is the gap space between the two electrodes. The upper plate of the capacitor, known as the diaphragm, will deform in response to an applied pressure and finally will come into contact with the dielectric thin film. Since the permittivity and the thickness are constant values, the capacitance C will only depend on the touching area A. Consequently we can measure the applied pressure to the diaphragm by reading the capacitance.

Bottom Line: Power transfer was done by magnetic induction coupling method, by placing one of the inductors of the Maxwell-Wien bridge circuit and the inductor of the implant in close proximity.The Maxwell-Wien bridge circuit was biased with a 10 MHz sinusoidal signal.In order to have a proper inductive coupling link, special care must be taken when placing the two coils in proximity to avoid misalignment between them.

View Article: PubMed Central - PubMed

Affiliation: Graduate Department, National Polytechnic Institute of Mexico (IPN), ESIME UPC, Avenida Santa Ana 1000, San Francisco Culhuacan, 04260 Mexico City, DF, Mexico.

ABSTRACT
An analysis of the effect of distance and alignment between two magnetically coupled coils for wireless power transfer in intraocular pressure measurement is presented. For measurement purposes, a system was fabricated consisting of an external device, which is a Maxwell-Wien bridge circuit variation, in charge of transferring energy to a biomedical implant and reading data from it. The biomedical implant is an RLC tank circuit, encapsulated by a polyimide coating. Power transfer was done by magnetic induction coupling method, by placing one of the inductors of the Maxwell-Wien bridge circuit and the inductor of the implant in close proximity. The Maxwell-Wien bridge circuit was biased with a 10 MHz sinusoidal signal. The analysis presented in this paper proves that wireless transmission of power for intraocular pressure measurement is feasible with the measurement system proposed. In order to have a proper inductive coupling link, special care must be taken when placing the two coils in proximity to avoid misalignment between them.

Show MeSH
Related in: MedlinePlus