Abstract: A method for providing an optical element may include providing an optical feature in the optical element that spreads or distributes light passing through the optical element. The method may also include providing a texturing in at least a portion of the optical feature of the optical element.

Abstract: An active layer has a quantum well structure formed of InGaAsP, and includes a saturable absorption region and optical amplification regions. To the saturable absorption region, a voltage is applied through a p-electrode, independent from the optical amplification region. To the optical amplification regions, currents are injected through p-electrodes, respectively. An input light Pin entering through a plane of incidence is generated by adding optical noise of white noise, to a light signal assuming binary optical intensity of “1” or “0”. The saturable absorption region and optical amplification regions are formed satisfying conditions that a waveform converting element provides a semiconductor laser of bistable state.

Abstract: Vertical cavity semiconductor optical amplifiers for various photonic devices including all optical logic gate devices and oscillators, where such devices can be implemented to achieve various advantages, including Boolean inversion at high speeds, low power, workable noise margins for cascadability because of input output isolation, and easy of integration in large arrays.

Abstract: A system for equalizing pulse to pulse energy of a light beam includes a group of optical devices including an optical device configured to exhibit third order nonlinear properties. Transmission properties of an unequalized light beam passing through the group of optical devices change such that an output intensity of a resulting light beam output from the optical devices is equalized. One example configuration includes a beam splitter, a nonlinear interference filter, a mirror and a beam combiner. A first portion of the light beam that is reflected from the nonlinear interference filter is combined with the light beam such that a resulting combined light beam has equalized output intensity. Another example includes at least first and second prisms having third order nonlinear properties and configured as a beam steering system. A lithography system and a method of equalizing pulse to pulse energy in a light beam are also presented.

Abstract: Embodiments of a periodically filtered broadband light source are described. The periodically filtered broadband light source includes a periodic spectral filter coupled to an optical gain element to generate a light and to filter the light into a plurality of individual spectral slices. The broadband light source includes an isolator coupled to the optical gain element. The periodic filter can be a reflective filter. The periodic filter can adjust an optical power in each of the spectral slices. The periodic filter can include one or more control elements to control an optical power in each of the spectral slices. Further, a wavelength division multiplexing passive optical network system is described that includes the periodic broadband light source to send individual spectral slices to wavelength lock one or more transceivers. The individual spectral slices sent by the periodic broadband light source match wavelength channels of a wavelength division multiplexer/de-multiplexer.

Abstract: A device for generating a plurality of laser pulses from a recirculating single laser pulse in an optical delay line that is capable of partially transmitting the trapped pulse out of the delay line. The energy of the partially reflected trapped pulse is restored before beginning another round trip in the delay line. The time structure of an output pulse train thus generated by the device comprises a sequence of macro pulses, each comprising a plurality of micro pulses.

Abstract: An optical wavelength converter based on cross-gain modulation with wide input dynamic range, the converter including a semiconductor optical amplifier, a continuous wave source, and a probe beam controller. The semiconductor optical amplifier modulates probe power on the basis of pump power. The continuous wave source generates the probe beam and supplies the generated probe beam to the semiconductor optical amplifier. The probe beam controller adjusts bias current supplied to the continuous wave source and controls the probe power in proportion to the pump power.

Abstract: An optical window signal generator which begins generation of an optical output signal in response to an optical activation pulse, and terminates generation of the optical output signal in response to an optical deactivation pulse. The rise time of the optical output signal is equal to the rise time of the optical activation pulse, and its fall time is equal to the rise time of the optical deactivation pulse.

Abstract: A method and apparatus for data conversion using time manipulation is disclosed. Ultrafast analog-to-digital (A/D) conversion and digital-to-analog I/A) conversion are achieved by optoelectronic time-stretching or time-compression, respectively. A pulsed laser is chirped by frequency spreading the laser output in either discrete or continuous fashion. The chirped output is then modulated with the electrical signal, and then frequency spread again. The output of the modulated signal is detected with a photodetector to convert the optical signal to a time-manipulated copy of the electrical signal.

Abstract: The all-optical pulse generating and amplifying system utilizes a phosphor that is excited by input light of a first wavelength and, in response, emits light of a second wavelength. The light emitted by the phosphor illuminates a bistable element which, at a pre-fixed intensity of the phosphor-emitted light, switches from non-transmissive state to transmissive state, thereby allowing the exit of light (also of first wavelength) emitted by an output light source as light pulse output of the system. An inhibitory light that also passes through the bistable element during its transmissive state quenches the phosphor light emission and returns the bistable element to its non-transmissive state and re-starts the process toward the next transmissive state. By gating the intensity, via selected non-linearity of the bistable element, of the light output in proportion to the intensity of the input light, the system can also function as an amplifier.

Abstract: The invention relates to a wavelength conversion apparatus for transmitting data carried by an incident pump wave beam of wavelength .lambda. to a probe wave of wavelength .lambda..sub.s. The apparatus has two semiconductor optical amplifiers and means for splitting the incident pump wave beam so as to inject a respective secondary pump wave beam into each of said optical amplifiers, said optical amplifiers are connected in series on the path of the probe wave so that each of them modulates said wave in intensity with the corresponding secondary pump wave beam by means of a crossover gain-saturation phenomenon.

Abstract: An optical signal regenerator has a semiconductor laser in a resonant cavity defined by a mirror and a semireflective facet of the laser to form a resonant, non-linear, optical amplifier. A polarization beam splitter allows resonance in one polarization mode only. A clock signal generator provides clock signals in the resonant polarization mode of a power just below the optical power bistable threshold of the amplifier. An information signal coupled to the laser by a lens and the beam splitter is in a non-resonant mode of the amplifier and will give rise to a regenerator output by triggering the bistability. Because the information signal is in a non-resonant mode its wavelength need not be controlled to lie near a resonance peak of the amplifier so reducing control requirements.

Abstract: An optical fiber amplifier has a lossy nonlinear medium connected between its input port and its output port. The resultant optical feedback loop permits remote gain switching of the optical amplifier.

Abstract: An optical amplifier having a saturable absorption region is operated below the lasing threshold for the device. Non-linear effects and bistability are observable at temperatures above room temperature. A selected input wavelength .lambda..sub.i within the gain spectrum of the device is amplified and an output at the same wavelength .lambda..sub.i is produced. This is in contrast to the normal operation at threshold, where there is a wavelength shift to the lasing wavelength and, depending on the laser used for the naturable absorption device, the output may be multimode for a monomode input. Best gain is achieved by tuning the input wavelength to a peak of a Fabry-Perot mode in the gain spectrum for the amplifier.The amplifier may be used as wavelength controlled optical switch, when operated bistably, or as a regenerative amplifier when operated in the non-linear region without hysteresis effects.