Abstract: A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise various light excitation and detection configurations. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue. Other biologic information can be used in combination with the fluorescence properties to aid in the determination of a measure of tissue state. The invention also comprises apparatuses suitable for carrying out the method.

Abstract: A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise single wavelength excitation light, scanning of excitation light (illuminating the tissue at a plurality of wavelengths), detection at a single wavelength, scanning of detection wavelengths (detecting emitted light at a plurality of wavelengths), and combinations thereof. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue.

Abstract: We disclose apparatus that includes: (a) an enclosure including an aperture; (b) a prism mounted in the enclosure so that a surface of the prism is exposed through the aperture; (c) an optical assembly contained within the enclosure, the optical assembly including a radiation source and a radiation detector, the source being configured to direct radiation towards the prism and the detector being configured to detect radiation from the source reflected from the exposed surface of the prism; and (d) an electronic processor contained within the enclosure, the electronic processor being in communication with the detector. The apparatus can be configured so that, during operation, the electronic processor determines information about a sample placed in contact with the exposed surface of the prism based on radiation reflected from the exposed prism surface while it is in contact with the sample.

Abstract: We disclose an apparatus comprising: a hand-portable optical analysis unit including an optical interface; and a device configured to receive and releasably engage the hand-portable optical analysis unit. The device comprises: a housing; a sample unit in the housing; and a resilient member configured to bias the sample unit and the hand-portable analysis unit towards each other when the hand-portable optical analysis unit is received in the device to compress a sample disposed between the sample unit and the optical interface of the optical analysis unit. Methods of analyzing samples are also disclosed.

Abstract: A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise single wavelength excitation light, scanning of excitation light (illuminating the tissue at a plurality of wavelengths), detection at a single wavelength, scanning of detection wavelengths (detecting emitted light at a plurality of wavelengths), and combinations thereof. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue.

Abstract: Methods and systems for determining information about a sample are disclosed. The methods can include measuring spectral information for a sample and determining a quantity related to a signal-to-noise ratio for the spectral information, repeating the measuring and determining until a value of the quantity is beyond a threshold value, and comparing the spectral information to reference information to determine information about the sample.

Abstract: We disclose apparatus that includes: (a) an enclosure including an aperture; (b) a prism mounted in the enclosure so that a surface of the prism is exposed through the aperture; (c) an optical assembly contained within the enclosure, the optical assembly including a radiation source and a radiation detector, the source being configured to direct radiation towards the prism and the detector being configured to detect radiation from the source reflected from the exposed surface of the prism; and (d) an electronic processor contained within the enclosure, the electronic processor being in communication with the detector. The apparatus can be configured so that, during operation, the electronic processor determines information about a sample placed in contact with the exposed surface of the prism based on radiation reflected from the exposed prism surface while it is in contact with the sample.

Abstract: Disclosed are apparatus, kits, methods, and systems that include a radiation source configured to direct radiation to a sample; a detector configured to measure radiation from the sample; an electronic processor configured to determine infotmation about the sample based on the measured radiation; a housing enclosing the source, the detector, and the electronic processor, the housing having a hand-held form factor; an arm configured to maintain a separation between the sample and the housing, the arm including a first end configured to connect to the housing and a second end configured to contact the sample; and a layer positioned on the second end of the arm, the layer being configured to contact the sample and to transmit at least a portion of the radiation from the sample to the detector.

Abstract: An apparatus includes: a handheld Raman analyzer that can include: a common platform; a laser assembly mounted on a laser platform, the laser platform supported on the common platform by a first material and a second thermally conductive material wherein the first material is softer than the second material; an optical probe head assembly disposed on the common platform, the optical probe head assembly spaced apart from the laser assembly; a spectrometer assembly disposed on the common platform, the spectrometer assembly spaced apart from the optical probe head assembly; and an analysis apparatus configured to identify a specimen based on a Raman signature received from the spectrometer. The laser assembly can be optically coupled to the optical probe head assembly by at least a first free-space coupling region and the optical probe head assembly optically coupled to the spectrometer assembly by at least a second free-space coupling region.

Abstract: Methods and systems for determining information about a sample are disclosed. The methods can include measuring spectral information for the sample and determining a quantity related to a signal-to-noise ratio for the spectral information, repeating the measuring and determining until a value of the quantity is beyond a threshold value, and comparing the spectral information to reference information to determine the information about the sample.

Abstract: Methods and systems for determining information about a sample are disclosed. The methods can include measuring spectral information for the sample and determining a quantity related to a signal-to-noise ratio for the spectral information, repeating the measuring and determining until a value of the quantity is beyond a threshold value, and comparing the spectral information to reference information to determine the information about the sample.

Abstract: We disclose apparatus that includes: (a) an enclosure including an aperture; (b) a prism mounted in the enclosure so that a surface of the prism is exposed through the aperture; (c) an optical assembly contained within the enclosure, the optical assembly including a radiation source and a radiation detector, the source being configured to direct radiation towards the prism and the detector being configured to detect radiation from the source reflected from the exposed surface of the prism; and (d) an electronic processor contained within the enclosure, the electronic processor being in communication with the detector. The apparatus can be configured so that, during operation, the electronic processor determines information about a sample placed in contact with the exposed surface of the prism based on radiation reflected from the exposed prism surface while it is in contact with the sample.

Abstract: Methods for determining the most likely composition of sample are disclosed. The methods can include: obtaining data from a sample, where the data includes a representation of a measured spectrum; determining a precision state of the representation of the measured spectrum; providing a plurality of library candidates; for each library candidate, providing data representing each library candidate, where the data includes a representation of a library spectrum; determining a representation of the similarity of the sample to each library candidate; determining the most likely composition of the sample based upon the determined representations of similarity of the sample to each library candidate; and displaying the most likely composition of the sample to a user.

Abstract: We disclose apparatus that includes: (a) an enclosure including an aperture; (b) a prism mounted in the enclosure so that a surface of the prism is exposed through the aperture; (c) an optical assembly contained within the enclosure, the optical assembly including a radiation source and a radiation detector, the source being configured to direct radiation towards the prism and the detector being configured to detect radiation from the source reflected from the exposed surface of the prism; and (d) an electronic processor contained within the enclosure, the electronic processor being in communication with the detector. The apparatus can be configured so that, during operation, the electronic processor determines information about a sample placed in contact with the exposed surface of the prism based on radiation reflected from the exposed prism surface while it is in contact with the sample.

Abstract: We disclose an apparatus comprising: a hand-portable optical analysis unit including an optical interface; and a device configured to receive and releasably engage the hand-portable optical analysis unit. The device comprises: a housing; a sample unit in the housing; and a resilient member configured to bias the sample unit and the hand-portable analysis unit towards each other when the hand-portable optical analysis unit is received in the device to compress a sample disposed between the sample unit and the optical interface of the optical analysis unit. Methods of analyzing samples are also disclosed.

Abstract: This disclosure relates to optical measurement and identification of samples.

Abstract: We disclose apparatus that includes: (a) an enclosure including an aperture; (b) a prism mounted in the enclosure so that a surface of the prism is exposed through the aperture; (c) an optical assembly contained within the enclosure, the optical assembly including a radiation source and a radiation detector, the source being configured to direct radiation towards the prism and the detector being configured to detect radiation from the source reflected from the exposed surface of the prism; and (d) an electronic processor contained within the enclosure, the electronic processor being in communication with the detector. The apparatus can be configured so that, during operation, the electronic processor determines information about a sample placed in contact with the exposed surface of the prism based on radiation reflected from the exposed prism surface while it is in contact with the sample.

Abstract: A method for determining the most likely composition of a sample, including obtaining data from a sample, wherein the data includes a representation of a measured spectrum; determining the precision state of the representation of the measured spectrum; providing a plurality of library candidates and, for each library candidate, providing data representing each library candidate, wherein the data includes a representation of a library spectrum; determining a representation of the similarity of the sample to each library candidate using (i) the representation of the measured spectrum; (ii) the precision state of the representation of the measured spectrum; and (iii) the representation of the library spectrum for that library candidate; determining the most likely composition of the sample based upon the determined representations of similarity of the sample to each library candidate; and displaying the most likely composition of the sample to a user.

Abstract: A method of determining a measure of a tissue state (e.g., glycation end-product or disease state) in an individual. A portion of the tissue of the individual is illuminated with excitation light, then light emitted by the tissue due to fluorescence of a chemical with the tissue responsive to the excitation light is detected. The detected light can be combined with a model relating fluorescence with a measure of tissue state to determine a tissue state. The invention can comprise single wavelength excitation light, scanning of excitation light (illuminating the tissue at a plurality of wavelengths), detection at a single wavelength, scanning of detection wavelengths (detecting emitted light at a plurality of wavelengths), and combinations thereof. The invention also can comprise correction techniques that reduce determination errors due to detection of light other than that from fluorescence of a chemical in the tissue.

Abstract: Methods of reducing the effects of measurement device artifacts on a measurement of a sample are presented. A number of reference measurements performed with the measurement device are observed to identify reference independent components of the reference measurements. The variations of the reference independent components are used as surrogates for possible artifacts of the measurement device. A number of measurements of subjects similar to the sample are observed, and similarity components of the subject measurements that vary in a manner similar to the reference independent components may be identified. The sample measurement is then adjusted to remove at least part of the similarity components that correspond to the variations in the reference independent components. The adjustment of the sample measurement is thereby improved by reducing the effects of artifacts of the measurement device.