Abstract: A semiconductor forensic light kit is disclosed. The forensic light kit may use a variety of semiconductor light sources to produce light that contrasts forensic evidence against its background for viewing, photographing and collection. Example semiconductor light sources for the forensic light kit include light emitting diodes and laser chips. A heat sink, thermoelectric cooler and fan may be included to keep the forensic light cool. Removable light source heads may be included on the forensic light kit to provide for head swapping to give the user access to different wavelengths of light.

Abstract: A structure formed on a semiconductor wafer is examined by obtaining a first diffraction signal measured from the structure using an optical metrology device. A first profile is obtained from a first machine learning system using the first diffraction signal obtained as an input to the first machine learning system. The first machine learning system is configured to generate a profile as an output for a diffraction signal received as an input. A second profile is obtained from a second machine learning system using the first profile obtained from the first machine learning system as an input to the second machine learning system. The second machine learning system is configured to generate a diffraction signal as an output for a profile received as an input. The first and second profiles include one or more parameters that characterize one or more features of the structure.

Abstract: Devices and methods for processing multi-wavelength light beams and the single-wavelength components of such light beams are disclosed. In accordance with some embodiments, a spectral filter includes collimating and focusing optical elements, an apodizing filter, a diffraction grating, and a spatial filter. The collimating optical element collimates an input light beam while the apodizing filter spatially filters this beam. In general, the apodizing filter includes a range of transmissivity that varies according to a distance from a predetermined location on the apodizing filter. The diffraction grating diffracts the input beam which is focused by the focusing optical element onto the spatial filter to generate a filtered output beam. Embodiments of the invention may be employed as spectral filters, optical spectrum analyzers, optical mutiplexers, optical de-multiplexers, and the like.

Abstract: A method for separating fluorescence spectra of dyes present in a specimen (15) is disclosed. Firstly a spectral scan of the fluorescence spectrum of all the dyes present in the specimen (15) is performed. The fluorescence spectra associated with the respective dyes are stored in a database of the computer system. After spectral deconvolution of the acquired mixed fluorescence spectrum, a comparison is made between the measured individual spectra ascertained by spectral deconvolution and the fluorescence spectra associated with the respective dyes. Lastly, a linear deconvolution of the acquired mixed fluorescence spectrum is performed.

Abstract: The invention concerns a method for qualifying a diamond on the basis of a measured light transmission through the diamond, whereby the diamond is radiated by a light source which emits light having a wavelength in a range of 225 nm to 300 nm, whereby the transmission of said light through the diamond is compared to a reference value which corresponds to the transmission of said light through a reference diamond, which is a cut colourless or near colourless diamond with a concentration of A centers between 7 ppm and 22 ppm, and whereby the diamond is classified as natural and not colour-treated if the transmission through the diamond is smaller than or equal to the reference value.

Abstract: Systems and methods for measuring stress in a specimen are provided. One system includes an optical subsystem configured to measure stress-induced birefringence in patterned structures formed on the specimen. In some embodiments, the optical subsystem may be configured as a spectroscopic ellipsometer, a multi-angle laser ellipsometer, a polarimeter, a polarized reflectometer, or some combination thereof. The system also includes a processor coupled to the optical subsystem. The processor is configured to determine stress in a material of the patterned structures using the stress-induced birefringence measurements. One method includes measuring stress-induced birefringence in patterned structures formed on the specimen using an optical technique. The method also includes determining stress in a material of the patterned structures using the stress-induced birefringence measurements.

Abstract: In general, in one aspect, the invention features a method that includes directing a first measurement beam along a first path contacting a measurement object to determine a first interferometric phase related to a position of a measurement object, directing a second measurement beam along a second path contacting the measurement object to determine an second interferometric phase related to the position of the measurement object, and determining a contribution to the first interferometric phase due to perturbations in refractivity along the first path based on the second interferometric phase.

Abstract: A method and apparatus for determining color, presence and/or polarity of a component in a printed circuit board includes a sensor and an LED positioned behind a faceplate. The faceplate abuts the component and light is reflected from the LED off the component and received by the sensor. A resulting output signal is analyzed to determine the color, presence and/or polarity of the component in the printed circuit board, thereby ensuring that the printed circuit board is correctly assembled.

Abstract: A wavelength modulation spectroscopy method for measuring the concentration of a gas component is provided. A gas sample portion of the light is passed through a reference gas comprising the gas component in a constant concentration. Afterwards, the light is detected by a reference detector. Another portion of the light is passed through the gas sample and thereafter to a measuring detector. The light emitted by the light source is modulated with a frequency, while the wavelength is swept over a molecular absorption line of the gas component. Demodulation of the detector outputs is made at a higher harmonic. In order to compensate for variations of the modulation parameters of the light source in real time, a mathematical description of the demodulated reference detector output based on Fourier analysis of the modulated light and on a mathematical expression for the absorption line is provided.

Abstract: An apparatus for determining orientation of an alignment layer in a pixel unit of an LCD device is provided. The pixel unit includes a glass substrate having an outer surface provided with the alignment layer treated by photolithographic masking and rubbing operation. The apparatus includes a conveyor belt for feeding the alignment layer; a steam-generating device disposed above the conveyor belt in such a maimer that the alignment layer is formed with a plurality of water drops or water layer when passed underneath the steam-generating device; a light source for providing light beams into the water drops on the alignment layer; and an image catcher for fetching an image data formed on the alignment layer by virtue of light reflection and refraction of the water drops hanging on the alignment layer.

Abstract: A semiconductor source spectroscopy system controls optical power variation of the tunable signal due to polarization dependent loss in the system and thus improves the noise performance of the system. It relies on using polarization control between the source and the sample and/or the sample and the detector. In one example, the source has a semiconductor optical amplifier and an intracavity tunable element for generating a tunable optical signal for illuminating a sample. The tunable optical signal is spectrally tuned over a scan band of the spectroscopy system by operation of the intracavity tunable element.

Abstract: A mapping-measurement apparatus includes a light illumination unit, a photodetector for detecting, through an aperture, reflection light or transmission light from a sample, and adjustable scanning mirrors on the illumination and detection sides of the sample, each mirror having two independent rotational axes about which they can be independently rotated by a controller. The aperture restricts light incident on the photodetector from a predetermined portion of the sample surface.