Abstract: An acousto-optic deflector includes a body of material through which a laser beam to be modulated passes. The material has an acoustic attenuation in the range of 0.15 to 1.0 dB/?s-GHz2 and operates in a UV range of about 150 to 400 nm. A transducer is bonded to the body of material to launch a wave. An electronic driver drives the transducer.

Abstract: A photoelastic modulator, comprising a driving block and a driver transducer for perturbing said block in a predefined direction to establish a standing wave extending longitudinally in said block and hence perpendicularly to said predefined direction. The transducer is affixed to said block at two regions of the transducer mutually displaced in said predefined direction, to minimize the coupling of lateral perturbation perpendicular to the predefined direction. A recess or gap may be provided under the transducer.

Abstract: A laser apparatus includes a laser capable of generating a laser signal; means for conditioning the laser signal; and means for varying the beamwidth of the laser signal as it is scanned into the field of view.

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 beam combiner for combining at least two light beams (1, 2) into one combined light beam (3), in particular in the beam path of an optical arrangement, preferably of a microscope, is with respect to a flexible beam combination with structurally simple means characterized by an acousto-optical element (4) in which a mechanical wave or sound wave for deflecting or bending light beams can be generated, so that a first light beam (1) entering the acousto-optical element (4) and at least a second light beam (2) entering the acousto-optical element (4) exit the acousto-optical element (4) in a collinear manner as a combined light beam (3). Further, a light source with such a beam combiner is specified.

Abstract: To provide a laser scanning microscope including a laser beam source for stimulation that emits a laser beam for stimulation for applying photostimulation to a sample, a scanner that performs scanning with the laser beam for stimulation, a control device that controls the scanner, and an objective lens that condenses the laser beam for stimulation used for scanning by the scanner to the sample. The scanner has at least one acoustooptic device arranged on an optical path of the laser beam for stimulation. The control device determines a plurality of frequencies on the basis of the position and the range of a photostimulation region, and simultaneously applies the high-frequency signals of the determined plurality of frequencies to a vibrator attached to the acoustooptic device.

Abstract: In an embodiment, set forth by way of example and not limitation, a Bragg mirror includes a first bi-layer of a first thickness and a second bi-layer of a second thickness which is different from the first thickness. In this exemplary embodiment, the first bi-layer consists essentially of a first high impedance layer and a first low impedance layer, and the second bi-layer of a second thickness which is different from the first thickness, the second bi-layer consisting essentially of a second high impedance layer and a second low impedance layer. Preferably, the first bi-layer is configured to substantially reflect a first wavelength and the second bi-layer is configured to substantially reflect a second wavelength different from the first wavelength.

Abstract: A narrow-linewidth micropulse LIDAR transmitter based on a low-SBS single clad, small-mode-area optical fiber. High narrow-linewidth peak powers are achieved through the use of an erbium doped fiber with an acoustic waveguide. Over 6 ?J per pulse (100 ns pulse width) is achieved before a weak form of stimulated Brillouin scattering appears. This laser has the potential to scale to very high power in a low-SBS dual clad fiber.

Abstract: We disclose acousto-optic modulators that include: (a) an optical element configured to receive an input optical beam that propagates along a first direction; and (b) a transducer extending along the first direction and positioned on one or more surfaces of the optical element, the transducer having a transducer material positioned between two electrodes configured to apply a potential difference across the transducer to cause the transducer to generate an acoustic waveform propagating in a second direction in the optical element, and the input optical beam undergoing diffraction in a region of the optical element that includes the acoustic waveform.

Abstract: An acousto-optic (AO) frequency shifter includes an anisotropic crystal having an optical axis and an input face, and an acoustic transducer having electrodes affixed to the face for receiving an electrical signal and projecting an acoustic wave into the crystal. The anisotropic crystal is cut relative to the face so that the transducer is at an acoustic angle (?a) corresponding to a predetermined angle of incidence (?i) of an optical beam to be directed relative to the optic axis of the anisotropic crystal to substantially satisfy the parallel tangents phase matching condition.

Abstract: In an embodiment, set forth by way of example and not limitation, a Bragg mirror includes a first bi-layer of a first thickness and a second bi-layer of a second thickness which is different from the first thickness. In this exemplary embodiment, the first bi-layer consists essentially of a first high impedance layer and a first low impedance layer, and the second bi-layer of a second thickness which is different from the first thickness, the second bi-layer consisting essentially of a second high impedance layer and a second low impedance layer. Preferably, the first bi-layer is configured to substantially reflect a first wavelength and the second bi-layer is configured to substantially reflect a second wavelength different from the first wavelength.

Abstract: A photoacoustic apparatus includes an acoustic lens configured to collect a acoustic wave, an acoustic detector configured to detect the acoustic wave collected by the acoustic lens, a driver configured to move at least one of the acoustic detector and the acoustic lens so as to measure the acoustic wave generated from an object to be measured due to a photoacoustic effect, and a controller configured to output a first measurement signal resulting from the acoustic wave that is generated from a first position in the object, and to eliminate a second measurement signal resulting from the acoustic wave that is generated from a second position different from the first position in the object.

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: An acousto-optic modulator includes an acousto-optic bulk medium. A transducer is attached to the acousto-optic bulk medium and formed as a linear array of electrodes. A transducer driver is connected to each electrode and comprises a plurality of amplifiers connected to the electrodes such that each electrode is driven by a respective amplifier as a means to provide a low cost alternative to the use of higher power hybrid amplifiers in conventional AO device applications.

Abstract: Provided are equipment and a method for measuring a transmittance of a photomask. The system includes an acoustic optical deflector (AOD) substrate interposed between a light source and the photomask. The AOD is adapted to deflect a laser beam to an oblique incidence angle with respect to a surface of the photomask. A radio frequency (RF) signal source is coupled with the AOD substrate. Varying the frequency of the signal applied to the AOD substrate acts to change the refractive degree of the substrate, thereby changing an angle of deflection of the incident laser beam. A photodetector is positioned to receive the laser beam passing through the photomask and is adapted to measure an intensity of the laser beam which has penetrated the photomask. As a result, a transmittance of the photomask can be measured under off axis illumination (OAI).

Abstract: It is an object to perform high-precision observation by compensating group-velocity-delay dispersion and angular dispersion with a simple structure. The invention provides a laser microscope 1 including a light source; an acousto-optic deflector 7 that deflects ultrashort-pulse laser light L emitted from the light source; an angular-dispersion element 8, disposed in front of or after the acousto-optic deflector 7, that applies angular dispersion in a direction opposite to the acousto-optic deflector 7; and a group-velocity-delay dispersion-amount adjusting unit 10 that adjusts the amount of dispersion compensation by moving the angular-dispersion element 8 so as to vary the optical path length at each wavelength between the angular-dispersion element 7 and the acousto-optic deflector 8.

Abstract: An acousto-optic device having at least one groove on the backside improves acoustic termination of the device. The grooves can be added early in device fabrication and are compatible with batch processing, thereby avoiding the separate device handling. Grooving can be performed on the cell, before it is mounted to a batch plate. This simplifies batch plate processing by using a backside that remains parallel to the bondface.

Abstract: The present invention is a method and apparatus that utilizes an inertia-free diffraction mechanism to control both phase and rotation of the standing wave pattern that results in super-resolution at unparalleled imaging speeds. In some embodiments of the present inventions, AODs are utilized to control period, phase, and rotation of the SW pattern in contrast to the commonly used mechano-optical principles. This allows 2D (and 3D) super-resolution imagining at high stability and speed not limited by mechanical constraints. The present invention can be utilized, for example, for real time observations of dynamic processes in living cells.

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: An apparatus for processing a coherent light pulse comprises a piezoelectric material having an optical interface surface and a surface acoustic wave (SAW) producing device disposed on the piezoelectric material. A coherent light pulse is dithered at a high frequency when it is reflected off of or transmitted through the optical interface surface. The SAW-producing device may be adapted to generate a travelling SAW or a standing SAW on the optical interface surface.

Abstract: A system and method for increasing display brightness in laser illuminated display systems. An illumination source comprises a light source to produce colored light and a scanning optics unit optically coupled to the light source. The scanning optics unit scans the colored light along a direction orthogonal to a light path of the illumination source. The scanning optics unit comprises a diffuser to transform the colored light in beams of colored light, a scan optics element positioned in the light path after the diffuser, the scan optics element to move beams of colored light in a direction orthogonal to the light path with distinct beams of colored light separated by unilluminated space, and a lens element positioned in the light path after the scan optics element, the lens element to convert an angular refraction of the beams of colored light into a spatial deflection.

Abstract: A portable acousto-optical (AO) spectrometer system comprised of at least one AO crystal cell device specially designed for cancellation of side-lobe noise at a desired tuned wavelength of operation. Each AO crystal cell device has a transducer attached and forms an AO tunable filter (AOTF) and forms part of a photo-head assembly. The system can include an optical fiber link between the AO spectrometer photo-head assembly and additional features such as an optical alignment coupling attachment that couple an excitation source such as a laser that operates in either pulse or continuous mode, a probing fiber that provides a hand-held member that can emit a source radiation and in turn observe radiation reflected from an observed sample. There are two embodiment of the AO crystal cell device. Either embodiment of the AO crystal cell design can be used in the system, providing a vibration-insensitive AO spectrometer instrument having high sensitivity, accuracy and resolution capabilities.

Abstract: A corrosion resistant fluid cooled acousto-optic (AO) device includes an AO interaction medium and a piezoelectric transducer affixed to the AO medium. A cooling arrangement is thermally coupled to the AO medium and includes a first material, and at least one cooling conduit in thermal contact within the first material formed from a second different material having an inlet and an outlet coupled thereto. The conduit provides a channel having an inner surface for flowing a coolant fluid therethrough, wherein the conduit includes a continuous corrosion resistant material layer over its entire area of the inner surface. The first material provides a specific acoustic impedance closer to a specific acoustic impedance of the AO medium as compared to the corrosion resistant material, and a bulk thermal conductivity at 25 C of at least 75 W/m·K.

Abstract: An optical unit includes an acousto-optic deflector and a drive control unit. The drive control unit controls the acousto-optic deflector by changing a frequency of a voltage applied to an acousto-optic medium of the acousto-optic deflector to a frequency in a first frequency range during a first period representing a deflection control period and changing the frequency of the voltage to a frequency in a second frequency range different from the first frequency range during a second period representing a transmittance control period.

Abstract: A system and method for inspecting an object. The system includes: a traveling lens acousto-optic device adapted to generate a traveling lens that propagates through an active region of the traveling lens acousto-optic device; a first scanner, adapted to direct a beam of light towards the traveling lens while the traveling lens propagates; a first beam splitter, adapted to receive a beam formed by the traveling lens; and to split the scanned beam to multiple illuminating light beams; multiple detectors; and an objective lens; adapted to receive the multiple illuminating light beams, direct the multiple illuminating light beams towards multiple areas of the object, receive multiple collected light beams from the multiple areas of the object, and direct the multiple collected light beams towards the multiple detectors; wherein each detector is associated with an area of the multiple areas.

Abstract: An acousto-optic (AO) frequency shifter includes an anisotropic crystal having an optical axis and an input face, and an acoustic transducer having electrodes affixed to the face for receiving an electrical signal and projecting an acoustic wave into the crystal. The anisotropic crystal is cut relative to the face so that the transducer is at an acoustic angle (?a) corresponding to a predetermined angle of incidence (?i) of an optical beam to be directed relative to the optic axis of the anisotropic crystal to substantially satisfy the parallel tangents phase matching condition.

Abstract: A device for the optical splitting and modulation of monochromatic coherent electromagnetic radiation, in particular light beams and/or laser beams, contains a beam source, an acousto-optical element disposed downstream of the latter and serving for splitting the beam generated by means of the beam source into a number of partial beams, a modulator and also a signal generator for applying to the acusto-optical element an electrical signal for splitting the beam. The device is intended to be developed to the effect that in conjunction with a simple and functionally reliable construction and independently of the number of beams emitted by the beam source, the intensity of the individual split partial beams can be kept constant.

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: The present invention provides a device for trapping or stretching a microscopic substance comprising (a) a light source for irradiating laser beam; (b) an acousto-optic modulator (AOM) for regulating the direction of said laser beam irradiating from said light source; (c) a beam-expander for expanding and collimating the light beam emitting from said AOM; (d) an object lens for focusing the laser beam passing through said beam-expander; and (e) an incoherent light source for imaging said microscopic substance. The present invention further provides a method for trapping or stretching a microscopic substance comprising (a) providing a focused laser beam to form a focal spot and (b) scanning a plurality of points on said microscopic substance by said focal spot by way of the AOM.

Abstract: A method of processing light includes generating a beam of light and periodically diffracting the beam of light by an acoustooptic cell to produce diffracted light having at least one direction change from the generated light. The method further includes spatially integrating the diffracted light and providing the spatially integrated light to a spatial light modulator.

Abstract: An acousto-optic modulator includes an acousto-optic bulk medium and transducer attached to the acousto-optic bulk medium. The transducer includes an electrode circuit and plurality of piezoelectric platelet segments attached to the bulk medium and supporting the electrode circuit. The piezoelectric platelet segments are configured for reducing shear stress and susceptibility to fracture due to temperature extremes.

Abstract: An acousto-optic modulator includes an acousto-optic bulk medium. A transducer is attached to the acousto-optic bulk medium and formed as a linear array of electrodes. A transducer driver is connected to each electrode and comprises a plurality of amplifiers connected to the electrodes such that each electrode is driven by a respective amplifier as a means to provide a low cost alternative to the use of higher power hybrid amplifiers in conventional AO device applications.

Abstract: A method of laser drawing includes steps of causing laser light from a light source to be incident to an acousto-optical diffraction element, and deflecting the light incident to the element by changing a frequency of a high frequency signal to be inputted to the element to diffract the light, thereby changing a diffraction angle of the diffracted light, and condensing the diffracted light emerging from the element on an object to be processed as an optical spot, thereby scanning the object with the optical spot. A diffracted light intensity control table for controlling a light intensity of the diffracted light so as to be constant independent of the diffraction angle of the diffracted light is prepared in advance, and in the deflecting step, the light intensity of the diffracted light is controlled based on the diffracted light intensity control table.

Abstract: A method of suppressing distortion of a working laser beam directed for incidence on a target specimen presented for processing by a laser link processing system uses a spatial filter to remove stray light-induced distortion from the working laser beam.

Abstract: Detecting a pulse of a signal includes receiving the signal and a light beam. The signal drives a spatial light modulator to modulate the light beam, where the complex amplitude of the modulated light beam is proportional to the signal current. The modulated light beam passes through an optical system and is detected by an optical detector array. A processor identifies a portion of the signal comprising the pulse.

Abstract: In an embodiment, set forth by way of example and not limitation, a Bragg mirror includes a first bi-layer of a first thickness and a second bi-layer of a second thickness which is different from the first thickness. In this exemplary embodiment, the first bi-layer consists essentially of a first high impedance layer and a first low impedance layer, and the second bi-layer of a second thickness which is different from the first thickness, the second bi-layer consisting essentially of a second high impedance layer and a second low impedance layer. Preferably, the first bi-layer is configured to substantially reflect a first wavelength and the second bi-layer is configured to substantially reflect a second wavelength different from the first wavelength.

Abstract: Device for dispersion of light pulses of an optical beam constituted by two dispersive prisms with the same vertex angle, mounted head to tail, the optical input surface of the first prism being parallel to the optical output surface of the second prism, the distance separating the optical input surface of the first prism and the optical output surface of the second prism being adjustable, given that the material constituting at least one of the first and second prisms is an acousto-optic material allowing for acousto-optic interaction between the optical beam and an acoustic beam, the acoustic wave of the acoustic beam generating, in at least one of the first and second prisms, an integrated deflective Bragg cell.

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: An AOTF control apparatus, which applies an RF signal to an AOTF to allow a selected light to pass through the AOTF, includes: a first calculating unit calculating a relationship between a frequency of the RF signal and a wavelength of the selected light based on a frequency of the RF signal that allows a reference light to pass through the AOTF; and a second calculating unit calculating a relationship between a power of the RF signal and an attenuation amount of the selected light based on an input/output power of the reference signal at the input/output of the AOTF.

Abstract: A system and method for the temporal and phase modulation of beams through a series of electronically controlled grating modulators, as acousto optic devices (AODs), is provided where incoming electromagnetic radiation may be advanced or retarded by introducing a time delay of the associated optical phase fronts and implementing a varying chirped wave on an AOD.

Abstract: A regenerative amplifier includes a gain-medium that is optically pumped by CW radiation. The amplifier has primary resonator for amplifying pulses. The primary resonator has an optical switch for opening and closing the primary resonator. The amplifier has a secondary resonator that includes the gain-medium but not the optical switch. When the primary resonator is closed by the optical switch, and pulses are not being amplified, CW radiation is generated in the secondary resonator and prevents the gain-medium from being saturated. When the optical switch is operated to cause the primary resonator to amplify pulses, generation of CW radiation in the secondary resonator ceases.

Abstract: An acoustooptic filter 1 having an optical waveguide 3 disposed on an upper surface 2a of an acoustooptic substrate 2, an interdigital electrode 4 which excites a surface wave disposed on the acoustooptic substrate 2, a surface wave waveguide for the surface wave excited by the interdigital electrode 4 extends in substantially the same direction as the optical waveguide, and a mode of the light guided to the optical waveguide 3 is converted by the surface wave. The acoustooptic filter 1 includes a thin-film ridge 5 as a phase match condition changer that changes a phase match condition at a mutual action area by 0.235% or more from a state in which phases are matched, the mutual action area being an area where the surface acoustic wave and the light guided to the optical waveguide 3 act upon each other.

Abstract: A hyperspectral imaging system is tested in the lab to allow a determination of its response to the emission from a simulated target, of certain wavelengths of radiation which the imaging system will be using during target determination. A broadband IR wavelength generator is used to generate a multiplicity of wavelengths representing the target and an emissions simulator is used to generate wavelengths representing target emission of hot gases. An AOTF is used to delete one or more target wavelengths, and to add one or more emission wavelengths, from and to the transmission path to the imaging system.

Abstract: An acousto-optic (AO) device for generating a highly apodized acoustic wave field includes a piezoelectric transducer crystal for emitting an acoustic wave having a ground electrode disposed on one side of the piezoelectric crystal, and a patterned electrode layer disposed on a side of the piezoelectric crystal opposite the ground electrode. The patterned electrode layer includes a continuous region proximate to its center and a discontinuous region, a pattern in the discontinuous region including a plurality of spaced apart features electrically connected to the continuous region. An AO interaction crystal which receives the acoustic wave is attached to the ground electrode or the patterned electrode layer.

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: An acousto-optic modulator includes a (100), (010) or (001) single crystal silicon acousto-optic interaction medium, and at least one transducer for emitting an acoustic wave attached to the single crystal. The transducer has a first electrode layer disposed on one side and a second electrode layer disposed on its other side. The transducer is aligned to the single crystal so that the direction of acoustic propagation in the silicon crystal is substantially along the (100), (010) or (001) direction. A q-switched laser includes a modulator according to the invention.

Abstract: This document discusses, among other things, an imaging guidewire that includes one or more optical fibers communicating light along the guidewire. At or near its distal end, one or more blazed or other fiber Bragg gratings (FBGs) directs light to a photoacoustic transducer material that provides ultrasonic imaging energy. Returned ultrasound is sensed by an FBG sensor. A responsive signal is optically communicated to the proximal end of the guidewire, and processed to develop a 2D or 3D image. In one example, the guidewire outer diameter is small enough such that an intravascular catheter can be passed over the guidewire. Techniques for improving ultrasound reception include using a high compliance material, resonating the ultrasound sensing transducer, using an attenuation-reducing coating and/or thickness, and/or using optical wavelength discrimination.

Abstract: A communication system uses a beam of light; a beam expanding lens; a lens for collimating the expanded beam into a column of collimated light; a plurality of acoustic transducers to project acoustic emanations perpendicularly to the column of collimated light, wherein each of the acoustic transducers is placed with respect to the column of collimated light to affect a different region of the column; a lens for collecting the collimated light from the collimating lens and light as affected by the acoustic emanation, wherein the collimating lens focuses the collected collimated light at a focal region; an optical filter at the focal region to separate the light as affected by the transducers from light not so affected; and a detector for detecting the light affected by the acoustic emanations.

Abstract: According to a first embodiment the invention provides, for achieving fast multi-wavelength scanning in an acousto-optical deflector based confocal scanning microscope, dynamically adjusting an optical path of said an acousto-optical deflector based confocal microscope by mechanical means in accordance with a selected wavelength of a laser light beam, to compensate for astigmatism and collimation changes due to the change in input beam wavelength and modifying detected images of an object by electronic means to maintain alignment of the scan lines of the image at all wavelengths. According to a second embodiment the invention provides, for achieving fast multi-wavelength scanning in an acousto-optical deflector based laser confocal scanning microscope, dynamically adjusting drive parameters of the acousto-optical deflector in accordance with the selected wavelength of the input laser light beams, to maintain alignment of the scan lines of the image at all wavelengths.

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.