Patent FR797805A successfully refreshed from Google Patents.
Patent US4834532A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4834532A Expired / Lapsed US ⏱️ 0.0 years remaining

Devices and procedures for in vitro calibration of pulse oximetry monitors

Assignee: Oregon Health & Science University
•
Filing: 1986-12-05
•
Granted: 1989-05-30
•
Expires: 2006-12-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A device and method for calibration of pulse oximeters is disclosed. A standard specimen that has optical charactertistics of hemoglobin of a known oxygen saturation is placed in the light path of a pulse oximeter probe. The image of a pulse is also created by providing a filter that periodically increases and decreases the amount of light allowed to reach the sensor of the probe. In one embodiment, the filter can comprise a pair of polarizing filters rotated with respect to one another. In another embodiment, a wedge of a filtering medium, such as oxygenated blood, is reciprocated in the light path, the wide portions of the wedge attenuating a greater amount of light than the narrow portions.

Inventors

  • 👤 John E. Yount

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 14:26
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/27; G01N21/274; A; A61; A61B; A61B5/00; A61B5/145; A61B5/1495; A61B2560/00; A61B2560/02; A61B2560/0223; A61B2560/0228; A61B2560/0233; G01N21/31; G01N21/314; G01N2021/3144; G01N2201/00; G01N2201/12; G01N2201/127

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 112 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for creating an image of a pulse by varying the intensity of light received by said light detector and for providing a sample of material which simulates hemoglobin of known oxygen saturation between said source and detector as said pulse means creates said image; said pulse means comprising a polarization filter which periodically increases and decreases the amount of light which passes from said light source to said light detector.
Claim 2
Independent Claim 112 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for creating an image of a pulse by varying the intensity of light received by said light detector and for providing a sample of material which simulates hemoglobin of known oxygen saturation between said source and detector as said pulse means creates said image; said pulse means comprising a polarization filter which periodically increases and decreases the amount of light which passes from said light source to said light detector.
Claim 3
Independent Claim 123 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for creating an image of a pulse by varying the intensity of light received by said light detector and for providing a sample of material which simulates hemoglobin of a known oxygen saturation between said source and detector as said pulse means creates said image; said pulse means comprising a member which is reciprocated back and forth along a path of movement between said light source and light detector, said member having progressively changing light transmissivity along said path of movement.
Claim 4
Independent Claim 123 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for creating an image of a pulse by varying the intensity of light received by said light detector and for providing a sample of material which simulates hemoglobin of a known oxygen saturation between said source and detector as said pulse means creates said image; said pulse means comprising a member which is reciprocated back and forth along a path of movement between said light source and light detector, said member having progressively changing light transmissivity along said path of movement.
Claim 5
Independent Claim 150 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for creating an image of a pulse by varying the intensity of light received by said light detector and for providing a sample of material which simulates hemoglobin of a known oxygen saturation between said source and detector as said pulse means creates said image; said pulse means comprising a member which is reciprocated back and forth along a path of movement between said light source and light detector, said member being a cuvette defining a wedge-shaped chamber filled with a medium that has optical characteristics of hemoglobin of a known oxygen saturation so that the cuvette has a progressively changing light transmissivity along said path of movement.
Claim 6
Independent Claim 150 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for creating an image of a pulse by varying the intensity of light received by said light detector and for providing a sample of material which simulates hemoglobin of a known oxygen saturation between said source and detector as said pulse means creates said image; said pulse means comprising a member which is reciprocated back and forth along a path of movement between said light source and light detector, said member being a cuvette defining a wedge-shaped chamber filled with a medium that has optical characteristics of hemoglobin of a known oxygen saturation so that the cuvette has a progressively changing light transmissivity along said path of movement.
Claim 7
Independent Claim 127 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for simulating an image of a cardiovascular pulsation by gradually varying the intensity of light received by said light detector; said pulse means comprising a body of a light-absorbing medium which simulates hemoglobin of a known oxygen saturation, which body is moved along a path of movement between said light source and light detector, said body varying in thickness to be progressively changing in light transmissivity along said path of movement such that as said body is moved, said image of cardiovascular pulsation is simulated.
Claim 8
Independent Claim 127 words
A device for testing the accuracy of a pulse oximeter which comprises a light source and a light detector in opposing relationship to one another such that said source directs a beam of light toward said detector, said device comprising: pulse means for simulating an image of a cardiovascular pulsation by gradually varying the intensity of light received by said light detector; said pulse means comprising a body of a light-absorbing medium which simulates hemoglobin of a known oxygen saturation, which body is moved along a path of movement between said light source and light detector, said body varying in thickness to be progressively changing in light transmissivity along said path of movement such that as said body is moved, said image of cardiovascular pulsation is simulated.
Claim 9
Independent Claim 133 words
A method for testing the accuracy of a pulse oximeter wherein said pulse oximeter comprises a light source and light detector in opposing relationship to one another such that said light source directs a beam of light toward said detector, said method comprising: actuating said light source to shine light toward said detector; and creating an image of a pulse by placing a pair of parallel polarizing plates between said source and detector and then rotating one of said plates in a manner suitable to produce a variation of light intensity received by said source which mimics the variation of light intensity produced by a pulse and by providing a sample of material that simulates hemoglobin of a known oxygen saturation between said source and detector as said light intensity is being varied.
Claim 10
Independent Claim 133 words
A method for testing the accuracy of a pulse oximeter wherein said pulse oximeter comprises a light source and light detector in opposing relationship to one another such that said light source directs a beam of light toward said detector, said method comprising: actuating said light source to shine light toward said detector; and creating an image of a pulse by placing a pair of parallel polarizing plates between said source and detector and then rotating one of said plates in a manner suitable to produce a variation of light intensity received by said source which mimics the variation of light intensity produced by a pulse and by providing a sample of material that simulates hemoglobin of a known oxygen saturation between said source and detector as said light intensity is being varied.
Claim 11
Independent Claim 90 words
A method for testing the accuracy of a pulse oximeter wherein said pulse oximeter comprises a light source and light detector in opposing relationship to one another such that said light source directs a beam of light toward said detector, said method comprising: actuating said light source to shine light toward said detector; and creating an image of a pulse by providing a wedge of a light-absorbing medium, which wedge increases in thickness along a path of reciprocation, then reciprocating said wedge along said path between said source and detector.
Claim 12
Independent Claim 90 words
A method for testing the accuracy of a pulse oximeter wherein said pulse oximeter comprises a light source and light detector in opposing relationship to one another such that said light source directs a beam of light toward said detector, said method comprising: actuating said light source to shine light toward said detector; and creating an image of a pulse by providing a wedge of a light-absorbing medium, which wedge increases in thickness along a path of reciprocation, then reciprocating said wedge along said path between said source and detector.
Claim 13
Dependent Claim 15 words
The method of claim 6 wherein said wedge contains hemoglobin of a known oxygen saturation.
Claim 14
Dependent Claim 34 words
A cuvette suitable for use in testing the accuracy of a pulse oximeter, the cuvette defining a wedge-shaped chamber filled with a medium that has optical characteristics of hemoglobin of a known oxygen saturation.
Claim 15
Dependent Claim 34 words
A cuvette suitable for use in testing the accuracy of a pulse oximeter, the cuvette defining a wedge-shaped chamber filled with a medium that has optical characteristics of hemoglobin of a known oxygen saturation.

References Cited (Backward Citations)

US4167331A Cited
EP0102816A2 Cited
EP0104771A2 Cited
US4650327A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-05-29 1992-11-28 1993-05-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-05-29 1996-11-28 1997-05-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-05-29 2000-11-28 2001-05-30 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag