Abstract: Systems and methods relate to generating a self-consistent sediment model. Initially, void ratio extrema are determined for each sediment layer in a sediment column based on historical data or a direct measurement of the sediment column. Initial stress is determined for each sediment layer based on the void ratio extrema. A porosity model is generated for each sediment layer based on the void ratio extrema and the initial stress. At this stage, measured data is obtained for each sediment layer from a data collection device positioned at or near a geographic location of the sediment column. The porosity model of each of the sediment layer is combined with the measured data of the sediment layer to generate the self-consistent sediment model for each sediment layer. The porosity model and the self-consistent sediment model of each sediment layer is updated based on updated measured data obtained from the data collection device.

Abstract: An image measurement apparatus, which functions as a non-contact profile-measuring device, includes: an image sensor as an image pick-up device; a variable focal length lens (liquid lens unit) disposed on an optical axis extending from a workpiece to the image sensor; and a controller (image-pickup lens controller and image measurement processor) configured to control the variable focal length lens and process a detected image by the image sensor. The image measurement apparatus, which also functions as a non-contact displacement-detecting device, includes: an image sensor; a variable focal length lens (liquid lens unit) disposed on an optical axis extending from the workpiece to the image sensor; and a controller (displacement-detection lens controller and profile measurement processor) configured to control the variable focal length lens and a detected image by the image sensor.

Abstract: A variable focal length lens apparatus includes a liquid lens apparatus in which the refractive index changes in accordance with an input drive signal, and a drive controller that outputs the drive signal to the liquid lens apparatus. The drive controller includes a resonance lock controller that changes a frequency of the drive signal by tracking the drive signal to a resonance frequency of the liquid lens apparatus, and a tracking delayer that delays a change in the frequency of the drive signal that is due to the resonance lock controller.

Abstract: A vision system includes a variable focal length (VFL) lens system, a light source, an exposure time controller and a camera. The VFL lens system includes a tunable acoustic gradient index of refraction (TAG) lens that is controlled to provide a nominally sinusoidal modulation of a focus position. The light source includes a continuous illumination source connected to a source driver that drives the continuous illumination source based on a quasi-sinusoidal periodic drive function to provide corresponding quasi-sinusoidal periodic intensity modulated light. The camera provides a workpiece image based on an image exposure that inputs workpiece image light that arises from illuminating the workpiece with the quasi-sinusoidal periodic intensity modulated light. Utilization of the quasi-sinusoidal periodic intensity modulated light in combination with the nominally sinusoidal focus position modulation results in uniform image exposures and other advantages (e.g.

Abstract: A tunable acoustic gradient index of refraction (TAG) lens and system are provided that permit, in one aspect, dynamic selection of the lens output, including dynamic focusing and imaging. The system may include a TAG lens and at least one of a source and a detector of electromagnetic radiation. A controller may be provided in electrical communication with the lens and at least one of the source and detector and may be configured to provide a driving signal to control the index of refraction and to provide a synchronizing signal to time at least one of the source and the detector relative to the driving signal. Thus, the controller is able to specify that the source irradiates the lens (or detector detects the lens output) when a desired refractive index distribution is present within the lens, e.g. when a desired lens output is present.

Abstract: An apparatus for controlling an acousto-optical component influencing at least one of illumination light and detection light in a microscope is described. The apparatus comprises a radio-frequency generator for supplying the acousto-optical component with a radio frequency. The radio-frequency generator is configured to compensate deviations in the characteristics of the light due to temperature fluctuations in the acousto-optical component by adapting the radio frequency.

Abstract: The invention provides a method of laser processing with a thermally stabilized acousto-optic beam deflector.

Abstract: The invention relates to an external cavity tunable laser. The laser comprises an extracavity collimating lens arranged outside a laser cavity, and a laser output mirror, a laser gain medium, an intracavity collimating lens, an active optical phase modulator and a tunable optical filter all arranged sequentially inside the laser cavity. The laser further comprises an active polarization rotator arranged behind the tunable optical filter, a polarization beam splitter arranged behind the active polarization rotator, a first etalon and a first total reflection mirror arranged in the direction vertical to the optic axis of a laser cavity output lens, a second etalon and a second total reflection mirror arranged in the direction of the optic axis of the laser cavity output lens, and a laser drive and control circuit.

Abstract: A tunable acoustic gradient index of refraction (TAG) lens and system are provided that permit, in one aspect, dynamic selection of the lens output, including dynamic focusing and imaging. The system may include a TAG lens and at least one of a source and a detector of electromagnetic radiation. A controller may be provided in electrical communication with the lens and at least one of the source and detector and may be configured to provide a driving signal to control the index of refraction and to provide a synchronizing signal to time at least one of the source and the detector relative to the driving signal. Thus, the controller is able to specify that the source irradiates the lens (or detector detects the lens output) when a desired refractive index distribution is present within the lens, e.g. when a desired lens output is present.

Abstract: The invention provides a method of laser processing with a thermally stabilized acousto-optic beam deflector.

Abstract: Iterating an optical phase conjugation of ultrasonically-modulated diffuse light emitted by a scattering medium includes illuminating the scattering medium with a light beam from a coherent light source, modulating the diffuse light transmitted through the scattering medium with an ultrasonic wave focused on a region of interest within the scattering medium, fixing a hologram, retro-reflectively illuminating the scattering medium using a phase-conjugated copy of the diffuse light that was ultrasonically modulated, moving the ultrasonic focus, and iterating until light is focused on the final target.

Abstract: The invention provides a method of laser processing that includes the steps of: generating a sequence of RF pulses corresponding to a sequence of laser pulses having a laser pulse repetition rate, the RF pulses including transmitting RF pulses at transmitting RF frequencies and non-transmitting RF pulses at non-transmitting RF frequencies for causing the sequence of laser pulses to be deflected in respective transmitting and non-transmitting directions, each RF pulse comprising an RF frequency, an RF amplitude and a duration; controlling each RF pulse such that the sequence of RF pulses provides a modulated RF drive signal that is modulated to provide a balanced thermal loading on the acousto-optic deflector; applying the modulated RF drive signal to the acousto-optic deflector; and deflecting at least one laser pulse with the acousto-optic deflector using the modulated RF drive signal to irradiate a selected target position with a predetermined pulse energy.

Abstract: A tunable acoustic gradient index of refraction (TAG) lens and system are provided that permit, in one aspect, dynamic selection of the lens output, including dynamic focusing and imaging. The system may include a TAG lens and at least one of a source and a detector of electromagnetic radiation. A controller may be provided in electrical communication with the lens and at least one of the source and detector and may be configured to provide a driving signal to control the index of refraction and to provide a synchronizing signal to time at least one of the source and the detector relative to the driving signal. Thus, the controller is able to specify that the source irradiates the lens (or detector detects the lens output) when a desired refractive index distribution is present within the lens, e.g. when a desired lens output is present.

Abstract: A piezoelectric element drive circuit for outputting a signal that drives a piezoelectric element, the piezoelectric element drive circuit including: a frequency signal generation unit that outputs a frequency signal whose frequency is altered discretely; a voltage-controlled oscillator that alters the frequency of an output signal based on an inputted voltage; a phase comparator that compares the phase of the output signal from the frequency signal generation unit and the phase of the output signal of the voltage-controlled oscillator; and a loop filter that inputs, into the voltage-controlled oscillator, an output voltage that is altered based on alterations in an output signal from the phase comparator. The output signal of the voltage-controlled oscillator is the signal that drives the piezoelectric element.

Abstract: A tunable acoustic gradient index of refraction (TAG) lens and system are provided that permit, in one aspect, dynamic selection of the lens output, including dynamic focusing and imaging. The system may include a TAG lens and at least one of a source and a detector of electromagnetic radiation. A controller may be provided in electrical communication with the lens and at least one of the source and detector and may be configured to provide a driving signal to control the index of refraction and to provide a synchronizing signal to time at least one of the source and the detector relative to the driving signal. Thus, the controller is able to specify that the source irradiates the lens (or detector detects the lens output) when a desired refractive index distribution is present within the lens, e.g. when a desired lens output is present.

Abstract: A tunable acoustic gradient index of refraction (TAG) lens and system are provided that permit, in one aspect, dynamic selection of the lens output, including dynamic focusing and imaging. The system may include a TAG lens and at least one of a source and a detector of electromagnetic radiation. A controller may be provided in electrical communication with the lens and at least one of the source and detector and may be configured to provide a driving signal to control the index of refraction and to provide a synchronizing signal to time at least one of the source and the detector relative to the driving signal. Thus, the controller is able to specify that the source irradiates the lens (or detector detects the lens output) when a desired refractive index distribution is present within the lens, e.g. when a desired lens output is present.

Abstract: An output beam from a laser is directed into an acousto-optic cell. The laser beam includes repeated sequences of two or more pulses. The acousto-optic cell is sequentially driven by RF voltages at two or more frequencies. A portion of the laser output beam is diffracted by the acousto-optic cell at two or more different angles to the laser output beam. This provides two or more secondary beams. One of the secondary beams includes only the first pulses of the sequences; the other includes only the second pulses of the sequences. The duration of the pulses in the laser beam is controlled to control time-averaged power in the secondary beams.

Abstract: A system for controlling an acousto-optic device includes an acousto-optic device having an acoustic transducer and configured to store a number of design specific parameters for a parametric tuning algorithm. the system includes a frequency synthesizer coupled to the acousto-optic device and configured to provide a radio frequency tuning signal to the acousto-optic device via the acoustic transducer. A programmable controller is coupled to the acousto-optic device and the frequency synthesizer and wherein is configured to read the design specific parameters and to receive a second number of parameters comprising one or more of environmental parameters, setup specific parameters and user specified performance parameters. the programmable controller is also configured to apply the design specific parameters and the other parameters to the design specific parametric tuning algorithm to select a radio frequency tuning signal that optimizes a user specified performance parameter.

Abstract: A multiple beam generator for use in a scanning system, wherein the generator includes an acousto-optic deflector (AOD) which during use receives a laser beam and generates a deflected beam, the deflection of which is determined by an AOD control signal; a diffractive element which generates an array of input beams from the deflected beam; and a control circuit which during operation generates the AOD control signal and varies a characteristic of the first control signal to account for errors in the scanning system.

Abstract: Approaches to bias control are disclosed for an optical modulator that modulates an optical carrier with a data input signal. In one embodiment an electrical bias input signal provided to the modulator is adjusted based on a characteristic of the data input signal detected from the modulated optical output signal. Another embodiment injects an additive dither signal into an optical modulator receiving a data input signal having a modulation depth of at least on the order of 50%. These embodiments can obtain and maintain a correct bias point on a modulator's transfer function curve when the modulation signal has a modulation depth on the order of 100%.

Abstract: A broadband light source, such as a light-emitting diode (LED), such as a superluminescent light-emitting diode (SLED), has its mean wavelength stabilized by using a filter to pass a characteristic of the output of the source, detecting the filtered output, and adjusting a parameter affecting the wavelength of the source, such as drive current or temperature. A Gaussian or near-Gaussian filter can be used to obtain an intensity detection, or two narrowband filters can be used where one filter passes a wavelength greater, and one passes a wavelength less, than the desired mean wavelength.

Abstract: A scanning laser microscope is provided which includes at least one laser light source for emitting laser light, a plurality of modulating sections for adjusting the laser light emitted from each laser light source, a storage section for storing delay time information on an input/output of each modulating section, and signal production section for producing a driving signal to drive at least one modulating section selected from the plurality of modulating sections based on the delay time information of the at least one selected modulating section. The delay time information includes information on a response time from a start of driving to development of a function of each modulating section.

Abstract: A laser machining method and a laser machining apparatus superior in hole position accuracy and hole quality. An outgoing beam outputted as short pulses is shaped by a pulse shaping unit so as to form a #1 branch beam. The #1 branch beam is supplied to a portion to be machined, so as to machine the portion. In this case, the #1 branch beam may be controlled to synchronize with the outgoing beam. When a piece to be machined is made from a metal material and at least one of an organic material and an inorganic material, the metal material is machined with a laser beam shaped to have a pulse width not shorter than 100 ns, and at least one of the organic material and the inorganic material is machined with a laser beam shaped to have a pulse width shorter than 100 ns.

Abstract: A dynamic beam splitter including a beam deflector having a plurality of operative regions, the beam deflector being operative to receive a laser beam at a first one of the plurality of operative regions, the laser beam passing through the beam deflector, and to selectably direct the laser beam in response to a control input signal to pass through the beam deflector a second time. Methods for splitting a beam and for manufacturing an electrical circuit employing the dynamic beam splitter are also enclosed.

Abstract: Digital control of frequency and/or amplitude modulation techniques of an intracavity and/or extracavity AOM (60) facilitate substantially full extinction of a laser beam (90) to prevent unwanted laser energy from impinging a workpiece (80); facilitate laser pulse amplitude stability through closed-loop control of pulse-to-pulse laser energy; facilitate beam-positioning control including, but not limited to, closed-loop control for applications such as alignment error correction, beam walk rectification, or tertiary positioning; and facilitate employment of more than one transducer on an AOM (60) to perform any of the above-listed applications.

Abstract: Digital control of frequency and/or amplitude modulation techniques of an intracavity and/or extracavity AOM (60) facilitate substantially full extinction of a laser beam (90) to prevent unwanted laser energy from impinging a workpiece (80); facilitate laser pulse amplitude stability through closed-loop control of pulse-to-pulse laser energy; facilitate beam-positioning control including, but not limited to, closed-loop control for applications such as alignment error correction, beam walk rectification, or tertiary positioning; and facilitate employment of more than one transducer on an AOM (60) to perform any of the above-listed applications.

Abstract: Digital control of frequency and/or amplitude modulation techniques of an intracavity and/or extracavity AOM (60) facilitate substantially full extinction of a laser beam (90) to prevent unwanted laser energy from impinging a workpiece (80); facilitate laser pulse amplitude stability through closed-loop control of pulse-to-pulse laser energy; facilitate beam-positioning control including, but not limited to, closed-loop control for applications such as alignment error correction, beam walk rectification, or tertiary positioning; and facilitate employment of more than one transducer on an AOM (60) to perform any of the above-listed applications.

Abstract: Digital control of frequency and/or amplitude modulation techniques of an intracavity and/or extracavity AOM (60) facilitate substantially full extinction of a laser beam (90) to prevent unwanted laser energy from impinging a workpiece (80); facilitate laser pulse amplitude stability through closed-loop control of pulse-to-pulse laser energy; facilitate beam-positioning control including, but not limited to, closed-loop control for applications such as alignment error correction, beam walk rectification, or tertiary positioning; and facilitate employment of more than one transducer on an AOM (60) to perform any of the above-listed applications.

Abstract: Digital control of frequency and/or amplitude modulation techniques of an intracavity and/or extracavity AOM (60) facilitate substantially full extinction of a laser beam (90) to prevent unwanted laser energy from impinging a workpiece (80); facilitate laser pulse amplitude stability through closed-loop control of pulse-to-pulse laser energy; facilitate beam-positioning control including, but not limited to, closed-loop control for applications such as alignment error correction, beam walk rectification, or tertiary positioning; and facilitate employment of more than one transducer on an AOM (60) to perform any of the above-listed applications.

Abstract: A system for and method of generating electromagnetic radiation in which the radiation has both a first and second utility. The electromagnetic radiation is modulated to produce electronically detectable variations to achieve the second utility, the variations not affecting the first utility. In one embodiment, the electromagnetic radiation is visible light. In this embodiment, the first utility is illumination and the second utility is the transmission of data. In another embodiment, the invention provides a lamp for generating visible light capable of providing illumination and transmitting data to a receiver. Any variations in the visible light resulting from the data transmission are imperceptible by a human eye regardless of the nature of the data being transmitted. In yet another embodiment, a power line carrier modem or wireless network may be used with the present invention to transmit information to the source.

Abstract: A method and apparatus for information modulation for impulse radios are presented in both single-tone and pulse stream configurations. The modulation techniques include combinations of amplitude and phase modulation. The modulation techniques include both digital and analog schemes, including baseband on/off keying modulation, wavelet on/off keying modulation, pulse-position modulation, and FM modulation. Techniques for varying the modulation rate are also provided. Additionally, harmonics impulse ratio configurations are presented to take advantage of the modulation techniques.

Abstract: An acousto-micro-optic deflector (AMOD) is provided. This device uses a special combination of an acousto-optic deflector (AOD) and a micro-optic deflector (MOD) to provide agile gimballess beam steering over large angles. The combination is driven such that the entire field of regard of the device is accessible, and continuous contact with the target point is maintained.

Abstract: A laser beam intensity modulation system has a variable delay circuit that is used to control the relative delay in the delivery of a video signal between two cascaded AOM's. This delay circuit is controlled by a delay controller that monitors the intensity modulation of the laser beam to provide feedback control. This system maximizes the rise and fall times of the beam to generate precise beam modulation required for high speed image setters.

Abstract: An apparatus for minimizing vibration of images in video cameras due to vibration of the operator's hands includes a motion detector, an electric field generator which receives information from the motion detector and generate voltages related to the horizontal and vertical motions, and a hand vibration corrector which uses the voltages from the electric field generator to control the refractive index of a medium through which the incoming video images are passing, to thereby adjust the position of the incoming images. A CCD converts the optical signals of the hand vibration correcting means into electrical signals. The refractive index of the crystal having the electro-optical effect is controlled by electrical signals and the optical source of the input images is optically corrected. Consequently, a high speed response and high precision controlled resolution are provided. Further, the apparatus has a simple structure, and therefore, it can greatly contribute to the camera image stabilization.

Abstract: A folded acoustic traveling wave lens arrangement imparts multiple passes of an incident optical beam through the traveling wave lens, and thereby effectively maximize utilization of acoustic power. A lens of optically transmissive bulk material, such as quartz, is disposed in the path of an incident light beam which is spatially scanned by a light beam deflector. The bulk material of the lens element has a reflective layer disposed upon at least one of its surfaces, and is configured such that an incident light beam undergoes multiple passes through the acoustic wavefront propagating through the lens, prior to emerging from the lens. Aberration in the emerging beam due to multiple passes through the bulk material is corrected by a pupil plane correction plate.

Abstract: A light beam frequency comb generator uses an acousto-optic modulator to generate a plurality of light beams with frequencies which are uniformly separated and possess common noise and drift characteristics. A well collimated monochromatic input light beam is passed through this modulator to produce a set of both frequency shifted and unshifted optical beams. An optical system directs one or more frequency shifted beams along a path which is parallel to the path of the input light beam such that the frequency shifted beams are made incident on the modulator proximate to but separated from the point of incidence of the input light beam. After the beam is thus returned to and passed through the modulator repeatedly, a plurality of mutually parallel beams are generated which are frequency-shifted different numbers of times and possess common noise and drift characteristics.

Abstract: An optical, low-noise amplifier of the active-fiber type, which fiber contains a laser light emitting substance, adapted to be connected to an optical telecommunication fiber and receiving light therefrom at the transmission wavelength. The active fiber is also fed from a light source at a pumping wavelength and has a length corresponding to a partial absorption of the pumping light. Downstream of active fiber, there is a selective mirror device which reflects the light at the pumping wavelength and is transparent to the transmission wavelength light. Preferably, the mirror device consists of an optical demultiplexer adapted to separate the transmission wavelength and the pumping wavelength on two output fibers. A mirror which reflects the pumping wavelength is present at the end of the fiber carrying the pumping wavelength.

Abstract: An AOD driver (27) generates a driving signal of an AOD (11), whose frequency varies in response to a sweep signal and whose amplitude varies in accordance with an amplitude control signal. In an initial stage, a constant signal level is stored in a memory (29) and is supplied to the AOD driver. A laser beam is deflected by the AOD and the light intensity thereof is detected by a photo-sensor (14). A signal representing the light intensity is given to a CPU (33) and a corrected amplitude control signal is generated, which is stored in the memory in place of the original amplitude control signal to control the AOD driver.

Abstract: A light beam scanning apparatus comprises an ultrasonic light deflector for diffracting a light beam of a predetermined wavelength, and a reflecting mirror position approximately normal to light deflected by the ultrasonic light deflector for reflecting the deflected light and making it again impinge upon the ultrasonic light deflector.