Abstract: In a method of determining the position of an object, raw image data of the sky is recorded using a celestial imaging unit. The last known position, orientation, date, and time data of the object are obtained, and the position of a celestial body is measured. A latitude and longitude of the object is determined by matching the measured celestial body position to the expected celestial body position based on the input parameters. A system for determining a new position of an object comprises a celestial imaging unit configured to record image data of the sky, a signal processing unit, and a signal processing unit configured to receive and store in memory the image data received from the celestial imaging unit. The signal processing unit filters the image to find the positions of celestial objects in the sky. The signal processing unit is further configured to use roll and pitch from an IMU, and date and time from a clock to determine the object's position (latitude and longitude).

Abstract: In a method of determining the position of an object, raw image data of the sky is recorded using a celestial imaging unit. The last known position, orientation, date, and time data of the object are obtained, and the position of a celestial body is measured. A latitude and longitude of the object is determined by matching the measured celestial body position to the expected celestial body position based on the input parameters. A system for determining a new position of an object comprises a celestial imaging unit configured to record image data of the sky, a signal processing unit, and a signal processing unit configured to receive and store in memory the image data received from the celestial imaging unit. The signal processing unit filters the image to find the positions of celestial objects in the sky. The signal processing unit is further configured to use roll and pitch from an IMU, and date and time from a clock to determine the object's position (latitude and longitude).

Abstract: In a method for determining orientation of an object, raw image data of the sky is recorded using a sky polarimeter. One or more of Stokes parameters (S0, S1, S2), degree of linear polarization (DoLP), and angle of polarization (AoP) are calculated from the image data to produce a set of processed images. Last known position and time data of the object are obtained, and a known Sun azimuth and elevation are calculated using the last known position and time data. Roll and pitch of the object are found, and the roll and pitch data are used to find a zenith in the processed images. The yaw/heading of the object is determined using the difference between a polarization angle at the zenith and a calculated Sun azimuth.

Abstract: In a method for determining orientation of an object, raw image data of the sky is recorded using a sky polarimeter. One or more of Stokes parameters (S0, S1, S2), degree of linear polarization (DoLP), and angle of polarization (AoP) are calculated from the image data to produce a set of processed images. Last known position and time data of the object are obtained, and a known Sun azimuth and elevation are calculated using the last known position and time data. Roll and pitch of the object are found, and the roll and pitch data are used to find a zenith in the processed images. The yaw/heading of the object is determined using the difference between a polarization angle at the zenith and a calculated Sun azimuth.

Abstract: A system for determining a new orientation and/or position of an object comprises a sky polarimeter configured to record image data of the sky, a signal processing unit, and logic configured to receive and store in memory the image data received from the sky polarimeter. The logic calculates the Stokes parameters (S0, S1, S2,), DoLP, and AoP from the image data, detects obscurants and filters the obscurants (such as clouds and trees) from the image data to produce a filtered image. The logic is further configured to find the Sun and zenith in the filtered image, and to determine the roll, pitch, yaw, latitude and longitude of the object using the filtered image.

Abstract: A system for determining a new orientation and/or position of an object comprises a sky polarimeter configured to record image data of the sky, a signal processing unit, and logic configured to receive and store in memory the image data received from the sky polarimeter. The logic calculates the Stokes parameters (S0, S1, S2,), DoLP, and AoP from the image data, detects obscurants and filters the obscurants (such as clouds and trees) from the image data to produce a filtered image. The logic is further configured to find the Sun and zenith in the filtered image, and to determine the roll, pitch, yaw, latitude and longitude of the object using the filtered image.

Abstract: A system for determining a new orientation and/or position of an object comprises a sky polarimeter configured to record image data of the sky, a signal processing unit, and logic configured to receive and store in memory the image data received from the sky polarimeter. The logic calculates the Stokes parameters (S0, S1, S2,), DoLP, and AoP from the image data, detects obscurants and filters the obscurants (such as clouds and trees) from the image data to produce a filtered image. The logic is further configured to find the Sun and zenith in the filtered image, and to determine the roll, pitch, yaw, latitude and longitude of the object using the filtered image.

Abstract: A system for determining a new orientation and/or position of an object comprises a sky polarimeter configured to record image data of the sky, a signal processing unit, and logic configured to receive and store in memory the image data received from the sky polarimeter. The logic calculates the Stokes parameters (S0, S1, S2,), DoLP, and AoP from the image data, detects obscurants and filters the obscurants (such as clouds and trees) from the image data to produce a filtered image. The logic is further configured to find the Sun and zenith in the filtered image, and to determine the roll, pitch, yaw, latitude and longitude of the object using the filtered image.

Abstract: A method and apparatus are provided for accurately measuring the blood oxygen saturation with a retinal vessel. The apparatus includes an optical source for illuminating the retinal vessel with optical signals. The apparatus also includes a filter, such as an aperture, disposed within the path of the optical signals returning from the eye. The filter preferentially passes single pass optical signals that have diffused through the retinal layer and/or the choroidal layer of the eye while traversing the retinal vessel only once, while blocking or otherwise redirecting the other optical signals. The apparatus also includes a detector for separately detecting at least the single pass optical signals and, in some instances, the other optical signals as well. The apparatus can also include a processing element for determining the blood oxygen saturation in the retinal vessel based upon the optical signals that have been detected.

Abstract: A method and apparatus are provided for accurately measuring the blood oxygen saturation with a retinal vessel. The apparatus includes an optical source for illuminating the retinal vessel with optical signals. The apparatus also includes a filter, such as an aperture, disposed within the path of the optical signals returning from the eye. The filter preferentially passes single pass optical signals that have diffused through the retinal layer and/or the choroidal layer of the eye while traversing the retinal vessel only once, while blocking or otherwise redirecting the other optical signals. The apparatus also includes a detector for separately detecting at least the single pass optical signals and, in some instances, the other optical signals as well. The apparatus can also include a processing element for determining the blood oxygen saturation in the retinal vessel based upon the optical signals that have been detected.

Abstract: A probe for medical use includes a tip portion having a light energy input region for receiving light energy from a light source and a predetermined light energy output region whereby tissue subtended by the region may be irradiated by the light energy. The tip portion consists essentially of light propagating material having inclusions distributed therein for interacting with the light energy to produce a predetermined light energy output pattern. The light propagating material is a light propagating inorganic compound.

Abstract: A probe for medical use includes a tip portion having a light energy input region for receiving light energy from a light source and a predetermined light energy output region whereby tissue subtended by the region may be irradiated by the light energy. The tip portion consists essentially of light propagating material having inclusions distributed therein and generally throughout the tip portion between the light energy input region and the light energy output region for interacting with the light energy to produce a predetermined light energy output pattern. The light propagating material is a light propagating inorganic compound.