Abstract: Monitoring a bias point of an optical modulator includes receiving an optical signal modulated by the optical modulator. Photons of the optical signal are received at a photon reactive material operable to produce a reaction in response to the arrival of a predetermined number of photons. Reactions are produced in response to the arrival of the photons of the optical signal. Feedback is generated in response to the reactions. The feedback reflects the waveform of the optical signal, and indicates one or more bias points of the optical modulator.

Abstract: An optical communication apparatus for controlling the operating point of an optical modulation unit appropriately. An adding unit adds a bias voltage and a pilot signal. An optical modulation unit modulates light by an electrical signal, performs further modulation by a signal from the adding unit, and outputs an optical signal. A monitor unit monitors the level of the optical signal and outputs a monitor signal. A reference signal output unit outputs a reference in phase with the pilot signal contained in the monitor signal. A synchronous pilot-signal detection unit performs synchronous detection of the monitor signal by using the reference. A synchronous noise detection unit extracts noise from the monitor signal and performs synchronous detection of the noise by using the reference. A control signal output unit subtracts the synchronous detection value of the noise from that of the monitor signal, and outputs a control signal.

Abstract: A microelectromechanical (MEMS) device includes a substrate and a movable layer mechanically coupled to the substrate. The movable layer moves from a first position to a second position at a first rate and from the second position to the first position at a second rate faster than the first rate. The MEMS device further includes an adjustable cavity defined between the substrate and the movable layer and containing a fluid. The MEMS device further includes a fluid conductive element through which the fluid flows at a first flowrate from inside the cavity to outside the cavity upon movement of the movable layer from the second position to the first position and through which the fluid flows at a second flowrate slower than the first flowrate from outside the cavity to inside the cavity upon movement of the movable layer from the first position to the second position.

Abstract: The present invention provides systems and methods for chirp control of a dual arm Z-modulator to minimize dispersion in the fiber plant. The chirp control is based upon a real-time control loop based upon performance monitoring data between a transmitter and a receiver. Advantageously, the present invention enables improved performance in high-speed optical systems, and in some cases can eliminate or minimize the need for external dispersion compensation fiber (DCF).

Abstract: An illumination optical apparatus guides exposure light emitted from an exposure light source, to an illumination target object. The illumination optical apparatus has a plurality of spatial light modulation members arranged in an array form, and each spatial light modulation member is so configured that a plurality of reflecting optical elements each including a movable reflecting surface are arranged in an array form. At least one of the spatial light modulation members is arranged in an optical path of the light emitted from the light source.

Abstract: To optionally forming a multilevel light intensity distribution on an illumination pupil plane, the illumination apparatus implements Köhler illumination on an illumination target surface, using as a light source the light intensity distribution formed on the illumination pupil plane on the basis of light from a light source. The illumination apparatus has a spatial light modulator, a condensing optical system, and a control unit. The spatial light modulator has a plurality of reflecting surfaces which are two-dimensionally arranged and postures of which can be controlled independently of each other. The condensing optical system condenses light from the reflecting surfaces to form a predetermined light intensity distribution on the illumination pupil plane.

Abstract: In each light modulator element of a special light modulator with diffraction grating structure where moving ribbons and fixed ribbons are alternately arranged, the maximum light-amount (I1) when an output light-amount first becomes maximum from when the moving ribbons start to sag and the maximum light amount-voltage becoming an displacement amount (P1) at the maximum light-amount, are obtained and the minimum of a plurality of maximum light-amounts is set as a target ON light-amount (It). Since a voltage (corresponding to a displacement amount (Pt1)) between the maximum light amount-voltage and the minimum light amount-voltage at a displacement amount (P2) is obtained as a target ON-voltage for the target ON light-amount (It), it is thereby possible to prevent moving distance of the moving ribbons among ON/OFF from largely differing among the light modulator elements and achieve an appropriate image recording.

Abstract: An illumination optical system which illuminates an irradiated plane with illumination light provided from a light source includes a spatial light modulator which is arranged in an optical path of the illumination optical system and cooperates with part of the illumination optical system to form a desired light intensity distribution at a pupil position of the illumination optical system or a position optically conjugated with the pupil position. A detection unit detects the light intensity distribution of the illumination light at a position in an optical path extending from the light source to the spatial light modulator. The detection unit includes a light receiving surface which receives some of the illumination light. A control unit controls the spatial light modulator based on the light intensity distribution detected by the detection unit.

Abstract: The present invention provides a semiconductor light source module including: a semiconductor light source for emitting a light flux with a predefined wavelength; a SHG element for converting an incident light flux entering onto an incident end surface of the SHG element into an outgoing light flux having a different wavelength from the incident light flux; a light converging optical system for converging a light flux emitted from the semiconductor light source onto the incident end surface of the SHG element; a light receiving element for receiving a part of a light flux emitted from the SHG element; and a drive device for driving an optical element in the light converging optical system based on a light flux received by the light receiving element.

Abstract: A multiplexing technique for optical communications used to create a pseudo-random communications signal in the optical domain such that only the sender and/or receiver can decode the signal. The multiplexing technique may include one or more information-bearing optical signals combined with one or more dynamic pseudo-randomly-generated optical signals to create a combined dynamic subcarrier multiplexed privacy-protected output signal. The information-bearing signal is protocol-independent and can be of mixed type, such as RF, analog, and/or digital. Only the receiver of the privacy-protected signal may decode the pseudo-random signal so as to disclose the information-bearing signal. The present invention may use dynamic subcarrier multiplexing selection based on standard digital encryption and the use of optical range time to ensure synchronization.

Abstract: A method and system for aligning a spatial light modulator with respect to an imaging device is disclosed. An image of the spatial light modulator can be formed upon the imaging device and a controller can be used to position optical elements in a manner that effects translation, rotation, and scaling of the image so as to provide desired alignment. Such alignment can, for example, facilitate enhanced wavefront correction so as to at least partially compensate for the detrimental effects of atmospheric distortion in such applications as optical communications, imaging, and weaponry.

Abstract: Apparatus and methods relating to microscopes having specific control of the light that contacts a sample and/or a light detector, such as the eye of the user, a charge couple device or a video camera. The improved control includes enhanced, selective control of the angle of illumination, quantity of light and location of light reaching the sample and/or detector. The microscopes comprise one or more spatial light modulators in the illumination and/or detection light path of the microscope at one or both of the conjugate image plane of the aperture diaphragm of the objective lens and the conjugate image plane of the sample.

Abstract: In the bias stabilization control using average optical power of signal light, there is a case where a control algorithm (maximum control or minimum control) changes depending on the amplitude of clock voltage, or it becomes out of control. In an optical modulation device for performing CSRZ optical modulation on outgoing light from an optical source, control light inputted from a control light input path is inputted into an LN-MZ optical modulator having traveling-wave type modulating electrodes from a direction opposite to signal light, and the average optical power is detected by a photodetector. A bias-voltage Vb is so generated that this optical power may be minimized, and is applied to a bias input terminal, whereby automatic bias stabilization control is performed.

Abstract: A lighting system operating using a digital mirror as its operative device. The digital mirror is used to shape the light which is a passed through advanced optical devices in order to produce an output.

Abstract: Disclosed herein is an apparatus for calibrating the displacement of reflective parts in a diffractive optical modulator. The apparatus includes a diffractive optical modulator, a light intensity measurement unit, a projection unit, and display electronics. The light intensity measurement unit is disposed near one side of the diffractive optical modulator and measures and outputs the intensity of incident linear diffracted light having a predetermined diffraction order.

Abstract: An optical apparatus provided with an optical modulator having an periodic characteristic for input drive signal to output light, and modulating an input light into a signal light based on a tertiary drive signal with a bias level controlled to a level corresponding to a bottom of the periodic characteristic providing a minimum optical output; and a controller controlling the level of the signal light by controlling the amplitude of the a tertiary drive signal based on the monitored level of the signal light.

Abstract: An optical displacement sensor is disclosed that provides a optical displacement sensor that includes a optically-resonant cavity tuned to an operating wavelength without some of the disadvantages for doing so in the prior art. An embodiment of the present invention tunes an operating wavelength used with a Fabry-Perot interferometer to develop a desired relationship between the wavelength and the Fabry-Perot interferometer's initial cavity length.

Abstract: Optical communication apparatuses and optical communication methods are provided. According to one aspect, an optical communication apparatus includes a communication path configured to communicate a first signal; a signal generator configured to provide a second signal; a combiner configured to combine the first signal with the second signal to provide a composite signal; and a light source coupled with the combiner and configured to receive the composite signal and to output an optical signal corresponding to the composite signal to an optical conduit, wherein the signal generator is configured to monitor the application of the optical signal to the optical conduit and to alter the second signal responsive to the monitoring.

Abstract: An optical communications system comprising: an optical input and an output, a source of input signals in an asymmetric format and having a duty cycle, a modulator for modulating the input signals, to produce an asymmetric signal, the modulator comprising a Mach-Zehnder interferometer; drive means for driving the modulator at a predetermined modulator drive voltage; bias means for applying a bias voltage to the modulator; adjustment means for adjusting a first variable chosen from one of the bias voltage, gain voltage, or duty cycle in response to the relationship existing between changes in the amplitude of the asymmetric signal and changes in the first variable, characterized in that the system further comprising varying means for varying a second variable, different to the first variable and chosen from one of the bias voltage, gain voltage or duty cycle in response to adjustments made to the first variable; and a monitor for recording the average optical output power.

Abstract: A spatial light modulator may include a plurality of deflectable modulating elements. Each of the deflectable modulating elements may further include a support structure, an electrostatically deflectable mirror element and at least one electrode. The mirror element may be set to a deflection state by charging and selectively discharging a capacitor coupled to the at least one electrode.

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: The present invention provides a light transmitter with a stable IQ amplitude ratio relative to the characteristic change of a modulating system. The QPSK light modulator of the present invention includes a laser light source for outputting light; an optical demultiplexer for inputting light and branching it in two directions; two optical phase modulators for inputting respectively one of the branched lights; a ?/2 phase shifter provided before or after one of the two optical phase modulators; an encoder for inputting I and Q signals into the optical phase modulators through drivers; and an optical multiplexer for synthesizing the outputs of the two optical phase modulators into a multiplexed, modulated light. The QPSK light modulator includes another optical demultiplexer after the optical multiplexer and a correcting section for correcting amplitude unbalance generated when light passes between the optical demultiplexers, by using output from the second optical demultiplexer.

Abstract: In an optical modulation device (10) having an electrical/optical interaction region (11), an electrical signal line (3) is connected to an electrical signal input terminal (2a), another electrical signal line (4a) is connected to an electrical signal output terminal (2b), and a reflection control circuit (5) is connected to the other electrical signal line (4a). This reflection control circuit (5) is an impedance element which positively reflects an output electrical signal from the interaction region (11) of the optical modulation device (10). This makes it possible to raise the upper-limiting frequency at which the E/O (Electrical-to-Optical) response characteristic can be improved, and improve the flatness of the frequency characteristic of the E/O response without deteriorating the absolute value of the E/O response.

Abstract: A photonic oscillator includes an optical transceiver that serves the dual purpose of detecting a feedback RF lightwave signal carried on a laser beam and electrically filtering the RF lightwave signal to modulate the RF lightwave signal in accordance therewith, to thereby set up steady state oscillations in the modulated RF lightwave signal and thereby generate a multi-tone oscillating lightwave.

Abstract: A method and system for aligning a spatial light modulator with respect to an imaging device is disclosed. An image of the spatial light modulator can be formed upon the imaging device and a controller can be used to position optical elements in a manner that effects translation, rotation, and scaling of the image so as to provide desired alignment. Such alignment can, for example, facilitate enhanced wavefront correction so as to at least partially compensate for the detrimental effects of atmospheric distortion in such applications as optical communications, imaging, and weaponry.

Abstract: There is provided an optical substrate. The optical substrate includes at least one surface, The at least one surface includes at least one optical structure having a shape and dimensions, wherein the shape and dimensions of each optical structure represents in part a modulation of a corresponding idealized structure. The shape and dimensions of each of the at least one optical structure are determined in part by at least one randomly generated component of modulation wherein the modulation of each of the at least one optical structure is limited by a neighboring optical structure comprised by the surface.

Abstract: A light modulation apparatus including a Mach-Zehnder type light modulator, a driver for modulator outputting a control signal according to an input electric signal, a light branching circuit branching the output light signal, and a bias control circuit applying a bias voltage to the light modulator based on the branched light signal, the apparatus further comprises: a burst pause state detection circuit detecting a pause state of a burst signal included in the input electric signal; a photoelectric transducer converting an output light signal branched by the light branching circuit into an electric signal; a sampling circuit extracting the electric signal converted while the pause state is detected by the burst pause state; and a bias voltage adjustment circuit adjusting a bias voltage value of the bias voltage based on a voltage level of the extracted electric signal.

Abstract: In the bias stabilization control using average optical power of signal light, there is a case where a control algorithm (maximum control or minimum control) changes depending on the amplitude of clock voltage, or it becomes out of control. In an optical modulation device for performing CSRZ optical modulation on outgoing light from an optical source, control light inputted from a control light input path is inputted into an LN-MZ optical modulator having traveling-wave type modulating electrodes from a direction opposite to signal light, and the average optical power is detected by a photodetector. A bias-voltage Vb is so generated that this optical power may be minimized, and is applied to a bias input terminal, whereby automatic bias stabilization control is performed.

Abstract: In various embodiments, chromophores are described that include novel electron acceptors, novel electron donors, and/or novel conjugated bridges that are useful in nonlinear optical applications. In some embodiments, the present invention provides chromophore architectures wherein a chromophore contains more than one electron acceptor in electronic communication with a single electron donor, and/or more than one electron donor in electronic communication with a single electron acceptor. Also described is processes for providing materials comprising the novel chromophores and polymer matrices containing the novel chromophores. Electro-optic devices described herein contain one or more of the described electron acceptors, electron donors, conjugated bridges, or chromophores.

Abstract: The present invention aims at providing a drive control apparatus and a drive control method with a simple configuration, which can also reliably compensate for operating point fluctuations of an optical modulator driven in accordance with a drive signal corresponding to a clock signal. To this end, the drive control apparatus of the present invention is configured to supply, to an optical modulator of which the optical output characteristics with respect to drive voltage are changed periodically, a drive signal having a waveform corresponding to a clock signal, and the amplitude of which is set to around 2V?, detect the power of an optical signal output from the optical modulator, and control an operating point of the optical modulator so that an average value of the optical signal power becomes a maximum.

Abstract: This application describes use of an opto-electronic feedback in oscillators to suppress phase noise based on the high Q factor of the opto-electronic feedback.

Abstract: A linear opto-frequency chirp amount variable apparatus using a dielectric multilayer film mirror, which does not require the optical axis to be realigned each time the amount of a chirp is to be varied includes a pair of opposed, parallel, dielectric, multilayer film mirrors, and a movable mirror between the dielectric multilayer film mirrors. The movable mirror is inclined so that oblique, incident light, projected into the space between the two dielectric multilayer film mirrors, is reflected between them a plurality of times and then is reflected by the movable mirror into a direction parallel to the dielectric multilayer film mirror surfaces and in an incidence plane defined by the incident light and a plane-normal to each dielectric multilayer film mirror and toward the incident light. Moving the movable mirror forwards and backwards, parallel to the multilayer film mirrors changes the amount of a chirp.

Abstract: An electro-optical device includes an amplifier having an input receiving a data signal, a crossing adjustment input, and an output. The device includes a light source and a Mach-Zehnder modulator having a first input coupled to the output of the amplifier, an optical input coupled to the laser, a bias input, and an optical output. A bias circuit is coupled to the bias input of the Mach-Zehnder modulator and preferably includes a pilot signal generator connected to the crossing adjustment input of the amplifier, and a feedback circuit coupled between the optical output and bias input of the Mach-Zehnder modulator and coupled to the pilot signal generator. The bias circuit applies the pilot signal to the crossing adjust input of the amplifier which forces the modulator to the correct bias point for duobinary transmission. Modulation on +1 and ?1 levels is eliminated, and only the 0 level is modulated. The feedback loop forces modulated portion of the waveform to null bias.

Abstract: In some embodiments, a drive circuit may be coupled to a spatial light modulator, wherein the drive circuit provides a non-linear analog ramp signal to the spatial light modulator. Other embodiments are disclosed and claimed.

Abstract: An improved SLM that is capable of detecting when light incident on the SLM exceeds a predetermined threshold. A diode is fabricated around, or within the pixel array. Light incident on the array (and the diode) results in a current increase through the diode, which may detected and used to initiate a disable signal to control circuitry of the SLM.

Abstract: An optical modulator includes a crystal structure that exhibits polaritonic or excitonic behavior. A shock wave propagates through the crystal structure so as to optically modulate and manipulate a light signal propagating in the crystal structure.

Abstract: A modulator arrangement for modulating an optical signal using a quadrature phase shift key for use in an optical wavelength division multiplex (WDM) optical communications system comprising a laser (2) for producing an optical signal of a selected wavelength, which signal is split by a splitter (4), each part of said split signal being applied to a respective phase modulator (6, 8) each for which phase modulators is adapted to modulate the phase of the signal in dependence on a respective drive voltages. The phase of the output of at least one modulator (6) is shiftable at least in part by a phase shifter (10), the split signals being recombined by an optical recombiner (12) to form an optical phase shift key output, wherein the output power is monitored by a detector (20), the detector signal then being used to drive a feedback arrangement to control electrodes of the phase modulators (6, 8) and/or phase shifter (10).

Abstract: Illumination exposure control systems comprising reflective pixelated spatial light modulators that reflect substantially all of the light impinging on them into at least two different light paths. At least one of the light paths acts as a propagating light path and transmits the light beam out of the lighting system. At least one other light path acts as a non-propagating light path and prevents the light beam from being transmitted out the system. The illumination exposure control systems provide high speed of exposure actuation and precision control of exposure duration and frequency or exposure sequences.

Abstract: The optical transmission apparatus has a Mach-Zehnder optical modulator, a light source for applying an optical signal of a continuous light to the optical modulator, a driving circuit for inputting a driving signal into the optical modulator, a branching filter for taking out a part of an output optical signal, a photodiode for converting the taken-out output optical signal into an electric signal, a band pass filter for extracting a frequency component of a driving signal included in this electric signal, an error signal generator circuit for generating an error signal of a bias voltage that minimizes a value of the extracted frequency component, and a bias voltage control circuit for applying a bias voltage added with this error signal to the optical modulator.

Abstract: An improved analog optical system which provides improved dynamic range as well as sensitivity relative to known analog optical systems. The analog optical system includes a Mach-Zehnder modulator (MZM) operated with a low bias to improve sensitivity. In accordance with an important aspect of the invention, the optical system utilizes two optical wavelengths with two effective bias points to cancel even ordered distortion associated with low biasing. Two lasers having different wavelengths are applied to the Mach-Zehnder modulator by way of a wavelength division multiplexer (WDM). Alternately, a single laser producing two optical carriers having different wavelengths could be used in place of the two single wavelength lasers and the WDM. The modulator bias control circuit forces two optical carriers to two bias points on opposite sides of the minimum bias point thus, providing equal modulation depth with opposite sign on each of the two optical carriers.

Abstract: The present invention relates to an apparatus and method for automatically correcting a bias voltage for a carrier suppressed pulse generating modulator using the phase distribution of the output pulses, which automatically detects an optimal bias voltage for the carrier suppressed pulse generating modulator and stabilizes the bias voltage. In the bias voltage automatic correction method and apparatus of the present invention, an optimal bias voltage for the modulator is set to a bias voltage that is obtained when mean power of an optical signal output from the modulator is highest. The varying direction of the bias voltage is detected on the basis of the phase variations in the output optical signal of the modulator according to the bias voltage variations is detected, and the bias voltage is corrected oppositely to the varying direction of the bias voltage.

Abstract: The present invention relates to a method to reduce charging effects affecting a degree of movement of at least one movable micro mirror in a spatial light modulator, said at least one movable micro mirror is electrostatically attractable to at least one electrode, including the action of attracting electrostatically said at least one micro mirror in a sequence of reversed electrical field between said micro mirror and said at least one electrode.

Abstract: There is provided an optical substrate. The optical substrate includes at least one surface. The at least one surface includes at least one optical structure having a shape and dimensions, wherein the shape and dimensions of each optical structure represents in part a modulation of a corresponding idealized structure. The shape and dimensions of each of the at least one optical structure are determined in part by at least one randomly generated component of modulation wherein the modulation of each of the at least one optical structure is limited by a neighboring optical structure comprised by the surface.

Abstract: An optical function device capable of controlling an optical signal with another optical signal, wherein a modulated input light Iin of a wavelength ?1 is coupled with a bias light Ibias of a wavelength ?2, and the thus coupled input and bias lights are input to a first semiconductor optical amplifying element 48, so that the bias light Ibias is intensity-modulated in a phase reversed with respect to the input light Iin, while the input light Iin is cut by a first wavelength extracting element 56. A control light Ic of the wavelength ?1 is coupled with the intensity-modulated bias light Ibias of the wavelength ?2, and the thus coupled control and bias lights are input to a second optical amplifying element 50, so that the once reversed bias light Ibias of the wavelength ?2 is intensity-modulated with respect to the control light Ic of the wavelength ?1, and is extracted as an output light by a second wave extracting element 50.

Abstract: Techniques and devices using whispering gallery mode (WGM) optical resonators, where the optical materials of the WGM resonators exhibit an electro-optical effect to perform optical modulation. Examples of actively mode-locked lasers and other devices are described.

Abstract: A method and apparatus is provided for controlling the bias point of a Mach-Zehnder modulator. The method begins by applying a dither signal to a DC bias that is applied to a Mach-Zehnder modulator. A component of an optical output signal provided by the Mach-Zehnder modulator that is synchronous with the dither signal is detected. The dither signal is adjusted to maintain the detected component of the optical output signal at a substantially constant value.

Abstract: A high-energy optical beam generator providing a desired output waveform. The generator includes a master oscillator, such as a mode-locked laser, to generate an input beam, a first dispersive element to decompose the input beam into frequency components, a set of phase and amplitude modulators to modulate the frequency components individually, a set of power amplifiers to amplify the frequency components individually, and a second dispersive element to recombine the amplified and modulated frequency components into a single output beam. Phase control electronics control the modulators to provide the desired waveform for the output beam, based on its intended application and on sensed characteristics of the input beam and the output beam.

Abstract: The method according to the present invention includes the steps of splitting an optical signal into first and second optical signals, increasing the pulse widths of the first optical signal to obtain waveform shaped light, generating clock pulses according to the second optical signal, and inputting the waveform shaped light and the clock pulses into an optical AND circuit 10 to obtain a converted optical signal. According to the present invention, it is possible to suppress amplitude noise or the like generated in the optical AND circuit due to the jitter or temporal instability of the optical signal and the clock pulses.

Abstract: Disclosed is a method for generating patterns to be used in a spatial light modulator having a plurality of pixels. The method includes generating an optical pattern to be placed upon the pixels of the spatial light modulator, applying the optical pattern to the pixels of the spatial light modulator, measuring the optical performance of the plurality of pixels having the optical pattern applied to it, comparing the measured optical performance to a target optical performance, and adjusting the optical pattern applied to the plurality of pixels to form another optical pattern that more closely achieves the target optical performance.

Abstract: A spatial light modulator having a photo-detector for use in digital display systems is provided. The spatial light modulator modulates a light beam having multiple light components of different frequencies so as to produce color images. The photo-detector detects a component of the light beam and generates a timing signal. The timing signal is then used to synchronize the operation of the spatial light modulator with the sequence of incident light color components.