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US5251633A Expired / Lapsed US ⏱️ 0.0 years remaining

Optical probe

Assignee: HP Inc
•
Filing: 1991-08-08
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Granted: 1993-10-12
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Expires: 2011-08-08
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Abstract

Abstract An improved optical probe for the invasive measurement of partial carbon dioxide pressures is disclosed that minimizes pCO 2 reading drift. An optical probe for the invasive measurement of the partial carbon dioxide pressure comprises an optical fiber and a pCO 2 sensor. The pCO 2 sensor comprises a diffusion zone with a dye-containing gel that is optically sensitive to H + ions and a semi-permeable membrane that is permeable to CO 2 molecules, but is substantially nonpermeable to hydrogen ions Components of the pCO 2 sensor, such as the part of the optical fiber extending into the sensor or a reflector, are covered with a substance--preferably with a coating--that is substantially nonpermeable to hydrogen ions. This prevents the hydrogen ions from diffusing into the sensor components, which otherwise would cause an imbalance of hydrogen ions and, therefore, a drift in the pCO 2 reading.

Inventors

  • 👤 Martin Wunderling
  • 👤 Lothar Rupp
  • 👤 Martin Guenther

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 00:47
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/14539; A61B5/1455; A61B5/1459

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 120 words
An optical probe for the invasive measurement of at least the pCO 2 of a biologic circulatory system comprising: a pCO 2 sensor including (a) a sensing diffusion zone comprising a gel containing a dye that is optically sensitive to H + ions; and (b) components coupled to said gel including an optical element having an end portion in optical communication with the gel; and a semi-permeable membrane at least partially enclosing said pCO 2 sensor and said gel and components and comprising a material permeable to CO 2 molecules but substantially impermeable to H + ions; wherein at least one of said components is covered by a coating comprising a substance that is substantially impermeable to H + ions.
Claim 2
Dependent Claim 120 words
An optical probe for the invasive measurement of at least the pCO 2 of a biologic circulatory system comprising: a pCO 2 sensor including (a) a sensing diffusion zone comprising a gel containing a dye that is optically sensitive to H + ions; and (b) components coupled to said gel including an optical element having an end portion in optical communication with the gel; and a semi-permeable membrane at least partially enclosing said pCO 2 sensor and said gel and components and comprising a material permeable to CO 2 molecules but substantially impermeable to H + ions; wherein at least one of said components is covered by a coating comprising a substance that is substantially impermeable to H + ions.
Claim 3
Dependent Claim 17 words
The optical probe of claim 1 wherein said coating covers said end portion of said optical element.
Claim 4
Dependent Claim 32 words
The optical probe of claim 1 further comprising an optical reflector optically coupled to said optical element and a coating covering said optical reflector that is substantially impermeable to H + ions.
Claim 5
Dependent Claim 13 words
The optical probe of claim 3 wherein said optical reflector comprises a metal.
Claim 6
Dependent Claim 33 words
The optical probe of claim 1, wherein said coating comprising a substance that is substantially impermeable to H + ions is an adhesive for fastening said semi-permeable membrane to said gel and components.
Claim 7
Dependent Claim 26 words
The optical probe of claim 1 wherein said substance that is substantially impermeable to H + ions is silicone or a copolymer of silicone and polycarbonate.
Claim 8
Dependent Claim 23 words
The optical probe of claim 1 wherein the substance that is substantially impermeable to H + ions is hexamethyldisilazane or other silylating agent.
Claim 9
Dependent Claim 21 words
The optical probe of claim 1 wherein said adhesive is the coating that covers said at least one of said components.
Claim 10
Dependent Claim 129 words
An optical probe for the invasive measurement of at least the pCO 2 of a biologic circulatory system comprising: a pCO 2 sensor, said sensor having a diffusion zone with a dye-containing gel that is optically sensitive to H + ions; a semi-permeable membrane that is permeable to CO 2 molecules but substantially impermeable to H + ions at least partially enclosing said diffusion zone; an optical fiber comprising a plastic material extending into the pCO 2 sensor and through said semi-permeable membrane including an end portion of said plastic optical fiber juxtaposed with said dye-containing gel; and a coating covering at least said end portion of the plastic optical fiber extending into the pCO 2 sensor that comprises a substance that is substantially impermeable to H + ions.
Claim 11
Dependent Claim 129 words
An optical probe for the invasive measurement of at least the pCO 2 of a biologic circulatory system comprising: a pCO 2 sensor, said sensor having a diffusion zone with a dye-containing gel that is optically sensitive to H + ions; a semi-permeable membrane that is permeable to CO 2 molecules but substantially impermeable to H + ions at least partially enclosing said diffusion zone; an optical fiber comprising a plastic material extending into the pCO 2 sensor and through said semi-permeable membrane including an end portion of said plastic optical fiber juxtaposed with said dye-containing gel; and a coating covering at least said end portion of the plastic optical fiber extending into the pCO 2 sensor that comprises a substance that is substantially impermeable to H + ions.
Claim 12
Dependent Claim 31 words
The optical probe of claim 9 further comprising an adhesive for fastening the semi-permeable membrane to said sensor, said adhesive comprising a substance that is substantially impermeable to H + ions.
Claim 13
Dependent Claim 26 words
The optical probe of claim 9 wherein the substance that is substantially impermeable to H + ions is silicone or a copolymer of silicone and polycarbonate.
Claim 14
Dependent Claim 23 words
The optical probe of claim 9 wherein the substance that is substantially impermeable to H + ions is hexamethyldisilazane or other silylating agent.
Claim 15
Independent Claim 105 words
A method for manufacturing an optical probe for the invasive measurement of at least the pCO 2 of a biologic circulatory system including an optical component and a diffusion zone with dye-containing gel that is optically sensitive to H + ions enclosed within a semi-permeable membrane that is permeable to CO 2 molecules but substantially impermeable to H + ions, said method comprising the steps of: coating said optical component with a substance substantially impermeable to H + ions before the optical probe is assembled; and assembling the optical component such that the optical component is in juxtaposition to the gel within said semi-permeable membrane.
Claim 16
Independent Claim 105 words
A method for manufacturing an optical probe for the invasive measurement of at least the pCO 2 of a biologic circulatory system including an optical component and a diffusion zone with dye-containing gel that is optically sensitive to H + ions enclosed within a semi-permeable membrane that is permeable to CO 2 molecules but substantially impermeable to H + ions, said method comprising the steps of: coating said optical component with a substance substantially impermeable to H + ions before the optical probe is assembled; and assembling the optical component such that the optical component is in juxtaposition to the gel within said semi-permeable membrane.
Claim 17
Dependent Claim 54 words
The method of claim 13 wherein said probe includes a semi-permeable membrane that is permeable to CO 2 molecules and substantially impermeable to H + ions, said method further comprising the step of adhesively fastening said membrane to said optical components and diffusion zone using a substance substantially impermeable to said H + ions.
Claim 18
Dependent Claim 15 words
The optical probe of claim 8 wherein said optical element comprises a plastic fiber optic.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-10-11 1997-04-12 1997-10-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-10-11 2001-04-12 2001-10-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-10-11 2005-04-12 2005-10-12 $7700.00 Window Closed / Lapsed

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