摘要:
A laser and monitoring system is provided. In another aspect of the present invention, the system includes a laser, pulse shaper and detection device. A further aspect of the present invention employs a femtosecond laser and binary pulse shaping (BPS). Still another aspect of the present invention uses a laser beam pulse, a pulse shaper and a SHG crystal. In yet another aspect of the present invention, a multiphoton intrapulse interference phase scan (hereinafter “MIIPS”) method is used to characterize the spectral phase of femtosecond laser pulses and to correct them. A further aspect of the system of the present invention is employed to monitor environmental chemicals and biological agents, including toxins, explosives, and diseases.
摘要:
An interferometric sensing arrangement includes an interferometric sensor having an optical path length that varies depending on one or more physical parameters to be measured using the interferometric sensor. One or more light sources are used to generate light at three or more predetermined different fixed wavelengths. In a preferred example embodiment, four fixed wavelength lasers are used to generate light at four predetermined different fixed wavelengths. An optical coupler couples the multiple wavelength light to the interferometric sensor, and a detector measures an amplitude response of an interferometric signal produced by the interferometric sensor. A controller determines the optical path length based on the measured amplitude response.
摘要:
An interferometery system for making interferometric measurements of an object, the system including: a beam generation module which during operation delivers an output beam that includes a first beam at a first frequency and a second beam at a second frequency that is different from the first frequency, the first and second beams within the output beam being coextensive, the beam generation module including a beam conditioner which during operation introduces a sequence of different shifts in a selected parameter of each of the first and second beams, the selected parameter selected from a group consisting of phase and frequency; a detector assembly having a detector element; and an interferometer constructed to receive the output beam at least a part of which represents a first measurement beam at the first frequency and a second measurement beam at the second frequency, the interferometer further constructed to image both the first and second measurement beams onto a selected spot on the object to produce therefrom corresponding first and second return measurement beams, and to then simultaneously image the first and second return measurement beams onto said detector element.
摘要:
Methods for diagnosing vulnerable atherosclerotic plaque using optical coherence tomography to measure tissue optical properties, including backreflectance of heterogeneous layers, such as plaque cap, lipid pool composition and macrophage presence. Methods also include measurement of spatially and temporally dependent reflectance, measurement of multiple wavelength reflectance, low coherence interferometry, polarization and quantification of macrophage content.
摘要:
Provided are systems and methods for performing high-precision length measurement. One such system includes: an optical receiver, configure to receive a reflected optical pulse from a target; an optical combiner, configured to generate a combined optical pulse using the reflected optical pulse and a reference optical pulse; and a signal analyzer configured to determine a distance to the target using a depth of modulation value of the combined signal. A method as disclosed herein includes the steps of determining a first length component of a combined optical signal using a depth of modulation value and determining a second length component of the combined optical signal using a modulation period value.
摘要:
Provided are systems and methods for performing high-precision length measurement. One such system includes: an optical receiver, configure to receive a reflected optical pulse from a target; an optical combiner, configured to generate a combined optical pulse using the reflected optical pulse and a reference optical pulse; and a signal analyzer configured to determine a distance to the target using a depth of modulation value of the combined signal. A method as disclosed herein includes the steps of determining a first length component of a combined optical signal using a depth of modulation value and determining a second length component of the combined optical signal using a modulation period value.
摘要:
The invention relates to a device, for measuring the contrast of fringes in a Michelson interferometer at full field, comprising a Wollaston prism for diverting two perpendicular incident polarisations into two different emergent directions, said diverting means being arranged within the interferometer as substitute for a single polariser. The device is of application to a Michelson interferometer used in an OCT tomographical system and comprising means for obtaining interferometric contrast without use of a modulation technique or synchronous detection methods.
摘要:
A system and method for imaging of a sample, e.g., biological sample, are provided. In particular, at least one source electro-magnetic radiation forwarded to the sample and a reference may be generated. A plurality of detectors may be used, at least one of the detectors capable of detecting a signal associated with a combination of at least one first electro-magnetic radiation received from the sample and at least one second electro-magnetic radiation received from the reference. At least one particular detector may have a particular electrical integration time, and can receive at least a portion of the signal for a time duration which has a first portion with a first power level greater than a predetermined threshold and a second portion immediately preceding or following the first portion. The second portion may have a second power level that is less than the predetermined threshold, and extends for a time period which may be, e.g., approximately more than 10% of the particular electrical integration time.
摘要:
Methods and apparatus based on optical homodyne displacement interferometry, optical coherent-domain reflectometry (OCDR), and optical interferometric imaging are disclosed for overlay, alignment mark, and critical dimension (CD) metrologies that are applicable to microlithography applications and integrated circuit (IC) and mask fabrication and to the detection and location of defects in/on unpatterned and patterned wafers and masks. The metrologies may also be used in advanced process control (APC), in determination of wafer induced shifts (WIS), and in the determination of optical proximity corrections (OPC).
摘要:
A control system and apparatus for use with laser ionization is provided. In another aspect of the present invention, the apparatus includes a laser, pulse shaper, detection device and control system. A further aspect of the present invention employs a femtosecond laser and a mass spectrometer. In yet other aspects of the present invention, the control system and apparatus are used in MALDI, chemical bond cleaving, protein sequencing, photodynamic therapy, optical coherence tomography and optical communications processes.