Abstract:
A system and method for detecting dynamic changes that occur in a sample between a first time interval and a second time interval using a series of at least first and second sequential chemical images of the sample. During the first time interval: (i) the sample is illuminated with a plurality of photons to thereby produce photons scattered or emitted by the sample; (ii) a two-dimensional array of detection elements is used to simultaneously detect scattered or emitted photons in a first predetermined wavelength band from different locations on or within the sample; and (iii) the two-dimensional array of detection elements is thereafter used one or more further times to simultaneously detect scattered or emitted photons in one or more further predetermined wavelength band(s) from different locations on or within the sample. The outputs of the two-dimensional array of detection elements during the first time interval are then combined to generate the first chemical image of the sample. The process is repeated during the second time interval to generate the second chemical image of the sample. Dynamic changes occurring in the sample between the first time interval and the second time interval are detected based on one or more differences between the first and second chemical images.
Abstract:
Device for controlling light radiation, which is excited in a specimen and/or which is backscattered and/or reflected and which contains one or more wavelengths, at a plurality of light outlets, wherein a separation of the light radiation into differently polarized components is carried out; and the components of the excitation radiation and/or detection radiation are affected in their polarization by means of a preferably birefringent, preferably acousto-optic or electro-optic medium, which changes the ordinary and extraordinary refractive index.
Abstract:
The present invention discloses a spectral measurement method via continuous light source and discrete light source, and a measurement instrument for non-invasive detection of human body tissue components. Said instrument includes an incident unit, a probe, a receiving unit and a data processing unit. Said composite spectral measurement method improves or strengthens the output light intensity at the wavelength that carries information of the target component within human body. It enables the spectral detection in the whole wavelength range, and thus significantly enhances the SNR of the detecting system. In the non-invasive detection instrument, light from both the continuous light source and discrete light source can be firstly selectively light-split by AOTF, or AOTF conducts light-splitting for the continuous light source, while the discrete light source LD is controlled by a spatial chopper. When data of the spectral curves achieved from said continuous light source and discrete light source are processed, data acquired under different measuring modes can be compared.
Abstract:
A fluorescence subtracted Raman spectroscopy apparatus uses a wavelength modulated tunable filter as the spectrometer. The wavelength modulation results in an amplitude modulation on the detected optical signal. By using a frequency selective detection technique, the Raman signal is amplified and extracted from the fluorescence background.
Abstract:
Acoustic-optic devices which use a crystal of tellurium into which is launched acoustic shear waves by a lithium niobate transducer in accordance with an input RF signal. Tellurium used in the devices exhibits a figure of merit in the range of around 5,000 to 10,000.
Abstract:
A system and method for detecting dynamic changes that occur in a sample between a first time interval and a second time interval using a series of at least first and second sequential chemical images of the sample. During the first time interval: (i) the sample is illuminated with a plurality of photons to thereby produce photons scattered or emitted by the sample; (ii) a two-dimensional array of detection elements is used to simultaneously detect scattered or emitted photons in a first predetermined wavelength band from different locations on or within the sample; and (iii) the two-dimensional array of detection elements is thereafter used one or more further times to simultaneously detect scattered or emitted photons in one or more further predetermined wavelength band(s) from different locations on or within the sample. The outputs of the two-dimensional array of detection elements during the first time interval are then combined to generate the first chemical image of the sample. The process is repeated during the second time interval to generate the second chemical image of the sample. Dynamic changes occurring in the sample between the first time interval and the second time interval are detected based on one or more differences between the first and second chemical images.
Abstract:
A scanning tunable detection system and related method for analyzing samples includes a source of time varying excitation signals and a tunable optical filter for selectively transmitting time-varying optical signals emanated from a sample following irradiation with the time varying excitation signals. A detector is provided for converting the time-varying optical signals to electrical detection signals. The system can identify components in a sample using phase sensitive or time sensitive detection. A slew scan mode can be used to permit slow scanning through spectral regions rich in information but quickly in regions without such information.
Abstract:
A hemispherical detector comprising a plurality of photodetectors arranged in a substantially contiguous array, the array being substantially in the shape of a half-sphere, the half-sphere defining a closed end and an open end, the open end defining a substantially circular face. Also provided is a method for constructing a hemispherical detector comprising the steps of making a press mold of the desired shape of the hemispherical detector, pouring a material into the press mold to form a cast, finishing the cast to remove any defects, coating the cast with a coating material, and attaching a plurality of photodetectors to the cast.
Abstract:
The invention relates to a method and measuring device for determining at least one luminescence, fluorescence, or absorption parameter of a sample, including an excitation light source supplying the excitation radiation directed onto the sample, a detector unit for detection of the emission radiation (i.e., the radiation to be measured) given off by the sample, and an acousto-optical tunable filter (AOTF) being provided in the radiation path of the excitation radiation and/or in the radiation path of the emission radiation. The ultrasonic oscillations of the acousto-optical filter are excited by a high-frequency oscillator, which is furnished with a unit for amplitude modulation in the form of a rectangular, Gaussian, Hann, or Hamming window, thus providing an optical switch with switching times in the nullsec range.
Abstract:
In an optical spectrum analyzer comprising a spectrograph and a photodevice array, and an optical spectrum detecting method, a wavelength deviation, from an assigned wavelength, of a light detected by a photodevice array which detects a wavelength of a diffraction light or a non-diffraction light from an acoustooptic device, is detected and a feedback control to a diffraction angle of the acoustooptic device is performed. Also, without using a feedback control, an exit light and a diffraction light from the acoustooptic device are respectively received by two photodevice arrays and the photodevices are arranged in order to mutually compensate gaps between the photodevices, whereby a center of each photodevice is similarly made coincide with a peak of an optical beam to be received.