Patents (or Patents Pending)

US 6,647,279, Hybrid Optical Delivery System for Photoplethysmography

US 6,754,515, Stabilization Of Noisy Optical Sources in Photoplethysmography

US 7,430,444, Photoplethysmographic Device with Species Specific Calibration

US 8,078,251, Spring Wing Assembly for Photoplethysmographic Sensor

US 8,498,507, Anti-Reflective Launch Optics for Laser to Fiber Coupling in a Photoplethysmograpic Device

US 8,632,262, Laser to Fiber Optical Coupling in Photoplethysmograpic

EP 2,706,915, Anti-Reflective Launch Optics for Laser-Based Photoplethysmography

Pending US Patent Applications

White Papers

The following papers require a PDF reader. Click on the link to the right to get Adobe PDF Reader.

Pulse Oximetry - Where it Came From and Where it is Going

Laboratory CO-Oximetry and the Value of the Radiometer OSM3

Radiometer OSM3 Storage, Shipping, and Handling Tips

Radiometer OSM3 Hemoximeter Calibration Verification



 

US 6,647,279 B2

HYBRID OPTICAL DELIVERY SYSTEM FOR PHOTOPLETHYSMOGRAPHY

ABSTRACT
A hybrid optical system for photoplethysmographic measurements is disclosed. The system delivers light from a plurality of emitters to the tissue-under-test. A set of one or more of the emitters resides in close proximity to the sensor. A second set of one or more emitters resides at some distance from the sensor with the light from this second set of emitters being delivered to the sensor by a light pipe typically consisting of a fiber optic cable. This invention allows the photoplethysmographic instrument designer to use two or more different types of emitters in the same photoplethysmographic device while still generating a technically feasible and cost effective design.



(Return to Top of Page)

 

US 6,754,515 B1

STABILIZATION OF NOISY OPTICAL SOURCES IN PHOTOPLETHYSMOGRAPHY

ABSTRACT
A method and apparatus for photoplethysmographic measurements is disclosed. In this system light from a plurality of emitters is delivered to the tissue-under-test. A subset of one or more of the emitters is known to be quiet light sources with relatively stable output intensity levels and spectral contents. A second subset of one or more emitters is known to be relatively noisy light sources with output intensity levels that fluctuate over time. The use of noisy light sources may be necessary for the photoplethysmographic measurements due to favorable spectral output characteristics such as narrow spectral bandwidth or desirable center wavelengths for the measurement of the hemodynamic parameters or analytes of interest. This invention utilizes the quiet light sources to enable the use of noisy light sources without the loss in accuracy or precision of analyte measurement that would otherwise typically be associated with the use of noisy light sources in the design and use of a photoplethysmographic instrument.



(Return to Top of Page)

 

US 7,430,444 B2

PHOTOPLETHYSMOGRAPHIC DEVICE WITH SPECIES-SPECIFIC CALIBRATION

ABSTRACT
A method and apparatus for photoplethysmographic measurements from non-human species is disclosed. The extinction of light by hemoglobin, as a function of wavelength, varies as a function of the species of the subject being monitored. The calibration of a photoplethysmographic device should therefore also vary dependant upon the species of the subject. The photoplethysmographic device of this invention includes calibrations specifically designed to provide accurate readings on non-human subjects.


(Return to Top of Page)

 

US 8,078,251 B2

SPRING WING ASSEMBLY FOR PHOTOPLETHYSMOGRAPHIC SENSOR

ABSTRACT
A photoplethysmographic sensor designed for use on the presenting portion of a fetus during labor and delivery. The sensor has a non-deployed state in which the sensor presents a smaller footprint, or cross sectional area, for transvaginal insertion. Once the sensor is applied to the fetal tissue it is moved into the deployed state, which has a larger footprint or cross sectional area, than the sensor does in the non-deployed state. The deployed state optimizes the physical distance between the light emitter and the photodetector to maximize the photoplethysmographic measurement accuracy from the fetal tissue.




(Return to Top of Page)

 

US 8,498,507 B2

ANTI-REFLECTIVE LAUNCH OPTICS FOR LASER TO FIBER COUPLING IN A PHOTOPLETHYSMOGRAPHIC DEVICE

ABSTRACT
An embodiment of a light launching portion of a photoplethysmographic device having a laser light source and a light guide. The coupled end of the light guide includes an anti-reflection coating to prevent or minimize the back reflection of light emitted by the laser. This minimizes the extent to which back reflected light can re-enter the laser and adversely alter the optical output properties of the laser and additionally minimizes the associated light loss thus helping to maximize the optical coupling efficiency.




(Return to Top of Page)

 

US 8,632,262 B2

LASER TO FIBER OPTICAL COUPLING IN PHOTOPLETHYSMOGRAPHY

ABSTRACT
An embodiment of a laser to fiber coupling apparatus having a substrate that supports a laser mount, to which is affixed a submount and laser die, and an open slot mount, in which a light guide is affixed with an adhesive, such that the light from the laser is coupled into the light guide. The open slot arrangement permits the light guide to be moved in all six translational and rotational degrees of freedom to maximally couple the light from the laser to the light guide.




(Return to Top of Page)

 

European Patent No. 2706915 (France, Germany, and UK)

ANTI-REFLECTIVE LAUNCH OPTICS FOR LASER-BASED PHOTOPLETHYSMOGRAPHY

ABSTRACT
An embodiment of a light launching portion of a photoplethysmographic device having a laser (20) light source and a light guide (40). The coupled end of the light guide (40) includes an anti-reflection coating (30a) to prevent or minimize the back reflection of light emitted by the laser (20). This minimizes the extent to which back reflected light can re-enter the laser and adversely alter the optical output properties of the laser (20) and additionally minimizes the associated light loss thus helping to maximize the optical coupling efficiency. Other embodiments are described and shown.




(Return to Top of Page)

 

Pending Domestic (US) Patent Applications

Kestrel Labs has additional patents pending with the United States Patent Office (USPTO). For information on pending domestic patent applications, that have not yet been published by the USPTO, please contact the Company directly.


(Return to Top of Page)