Abstract:
A system for determining an analyte concentration in a fluid sample (e.g., glucose) comprises a light source, a detector, and a central processing unit. The detector is adapted to receive spectral information corresponding to light returned from the fluid sample being analyzed and to convert the received spectral information into an electrical signal indicative of the received spectral information. The central processing unit is adapted to compare the electrical signal to an algorithm built upon correlation with the analyte in body fluid. The algorithm is adapted to convert the received spectral information into the analyte concentration in body fluid. Spectral information is delivered from the central processing unit to the light source and used to vary the intensity and timing of the light to improve the accuracy of conversion into analyte concentration.
Abstract:
A spectroscopy system comprises a tunable semiconductor laser, such as an external cavity laser, that generates a tunable signal. A detector is provided for detecting the tunable signal after interaction with a sample. In this way, the system is able to determine the spectroscopic response of the sample by tuning the laser of the scan band and monitoring the detector's response. An integrating device, such as an integrating sphere, is interposed optically between the tunable semiconductor laser and the detector. This integrating device is used to mitigate the effects of parasitic spectral noise, such as noise that is generated by speckle or the combination of single- and multi-mode optical fibers in the transmission link between the tunable semiconductor laser and the detector.
Abstract:
An apparatus and method for determining a physical parameter affecting an optical sensor or a number of sensors in a network. The apparatus uses a narrow linewidth source at an emission wavelength λ e and an arrangement for varying the emission wavelength λ e of the radiation. An analysis module with curve fitting is used to generate a fit to the response signal obtained from the optical sensor. The physical parameter is determined form the fit rather than from the response signal. The apparatus can be employed with Bragg gratings, etalons, Fabry Perot elements or other optical sensors.
Abstract:
A multi-energy polarization imaging method consisting of a multi-fusion, dual-rotating retarder / multiple-energy complete Mueller matrix-based polarimeter and dual-energy capabilities, has been invented. The term multifusion describes the use of several imaging functions altogether such as polarimetric imaging, dual-energy subtraction, multifocal imaging and other. By substracting polarimetric parameters such as degree of polarization, degree of linear polarization, degree of circular polarization, respectively, obtained with interrogation light beams of wavelengths λ 1 and λ 2 , he system, enhanced imaging is obtained. The system includes a light source for illuminating a target with a first quantity of light having a first wavelength and a second quantity of light having a second wavelength, the first and second wavelengths being different. A polarization-state generator generates a polarization state for each of the first and second quantities of light, and includes a first polarizer through which the first and second quantities of light are transmitted before entering a first waveplate. A polarization-state receiver evaluates a resulting polarization state of the first and second quantities of light following illumination of the target, the polarization-state receiver including a second waveplate through which the first and second quantittes of light are transmitted before entering a second polarizer. An optical image-capture device captures a first image of the target illuminated by the first quantity of light and a second image of the target illuminated by the second quantity of light. A processing unit assigns a weighting factor to at least one of the first and second images and evaluates a weighted difference between the first and second images to generate a multi-energy image of the target.
Abstract:
A disc serving as a spatial radiation modulator has dispersed radiation filters thereon. Each filter has a transmittance or reflectance modulation function of the form sin (m theta + p pi /4), where m is a positive integer and p has one of the four values 0, 1, 2, 3. A radiation beam including selected wavelength components is diffracted into an elongated image dispersed according to wavelength. Different wavelength components are focused onto different filters on the modulator and are encoded by corresponding filters. Since the modulation functions of the filters are orthogonal to one another, it is possible to extract the amplitude of each wavelength component after it has been encoded or modulated by corresponding filter from the total detected signal during one measurement.
Abstract translation:用作空间辐射调制器的盘在其上具有分散的辐射过滤器。 每个滤光器具有形式为sin 2(mθ+ p pi / 4)的透射率或反射率调制函数,其中m是正整数,p具有四个值0,1,2,3中的一个。辐射 包括所选择的波长分量的光束被衍射成根据波长分散的细长图像。 不同的波长分量聚焦在调制器上的不同滤波器上,并由相应的滤波器编码。 由于滤波器的调制功能彼此正交,因此可以在一次测量期间从总检测信号对相应的滤波器进行编码或调制之后提取每个波长分量的振幅。
Abstract:
A disc serving as a spatial radiation modulator has dispersed radiation filters thereon. Each filter has a transmittance or reflectance modulation function of the form sin (m theta + p pi /4), where m is a positive integer and p has one of the four values 0, 1, 2, 3. A radiation beam including selected wavelength components is diffracted into an elongated image dispersed according to wavelength. Different wavelength components are focused onto different filters on the modulator and are encoded by corresponding filters. Since the modulation functions of the filters are orthogonal to one another, it is possible to extract the amplitude of each wavelength component after it has been encoded or modulated by corresponding filter from the total detected signal during one measurement.
Abstract translation:用作空间辐射调制器的盘在其上散布有辐射滤波器。 每个滤波器具有sin 2(m theta + p pi / 4)形式的透射率或反射率调制函数,其中m是正整数并且p具有四个值0,1,2,3中的一个。辐射 包括选定波长分量的光束被衍射成根据波长分散的细长图像。 不同的波长成分被聚焦到调制器上的不同滤波器上,并由相应的滤波器进行编码。 由于滤波器的调制功能彼此正交,所以可以在一次测量期间从总检测信号中提取每个波长分量的幅度,在每个波长分量已经被相应的滤波器编码或调制之后。
Abstract:
The selectivity, that is to say the ratio between the analyte-proportional signal and the foreign body-proportional signal is an essential factor in spectrometric measurements. When a narrow spectral band of the spectral domain is filtered by means of filter arrangements or the like and when supplying a detector of which the output signal is displayed, a sensitive improvement of the selectivity is obtained. The filter arrangement is periodically offset with respect to the spectral domain to be analyzed so that the spectral band passing through the filter arrangement is periodically offset through the spectral domain to be analyzed and the output signal from the detector is displayed through a lock-in amplifier of which the phase reference signal is proportional to the displacement.