133results about How to "High spectral purity" patented technology

A tunable transmissive grating comprises a transmissive dispersive element, a reflective element, and an angle θ formed between the two elements. A first optical path is formed according to the angle θ, wherein light dispersing from the dispersive element is directed onto the reflective element and reflects therefrom. At least one element is rotatable about a rotational center to cause a second optical path and thereby tune the wavelength of the light reflecting from the reflective element. Both elements can be rotatable together around a common rotational center point according to certain embodiments, and / or each element can be independently rotated around a rotational axis associated only with that element. According to some embodiments, the relative angle θ formed between the elements is held constant; however, in other embodiments θ can vary.

A spectral purity filter includes an aperture, the aperture having a diameter, wherein the spectral purity filter is configured to enhance the spectral purity of a radiation beam by reflecting radiation of a first wavelength and allowing at least a portion of radiation of a second wavelength to transmit through the aperture, the first wavelength being larger than the second wavelength. The spectral purity filter may be used to improve the spectral purity of an Extreme Ultra-Violet (EUV) radiation beam.

A multi-layer mirror includes on top of the multi-layer mirror a spectral purity enhancement layer, for example for application in an EUV lithographic apparatus. This spectral purity enhancement layer includes a first spectral purity enhancement layer, but between the multi-layer mirror and first spectral purity enhancement layer there may optionally be an intermediate layer or a second spectral purity enhancement layer and intermediate layer. Hence, multi-layer mirrors with the following configurations are possible: multi-layer mirror / first spectral purity enhancement layer; multi-layer mirror / intermediate layer / first spectral purity enhancement layer; and multi-layer mirror / second spectral purity enhancement layer / intermediate layer / first spectral purity enhancement layer. The spectral purity of normal incidence radiation may be enhanced, such that DUV radiation is diminished relatively stronger than EUV radiation.

A multi-layered spectral purity filters improveS the spectral purity of an Extreme Ultra-Violet (EUV) radiation beam and also collect debris emitted from a radiation source.

A reflective filter serving as a multi-bandpass filter for a light source configured to emit light in a plurality of color primary wavelengths to improve color purity. The addition of a reflective / recirculation assembly reinforces and recirculates light not passed by the multi-bandpass filter back into a desired spectrum, which is subsequently passed by the multi-bandpass filter, or converts light not passed by the multi-bandpass into electrical energy for use by the system. The reflective filter, solely or along with the recirculation assembly, can be placed adjacent a conventional light source. Alternatively the multi-bandpass filter and the recirculation assembly can be placed in a modified light source, or placed in an optical stack along the path of light emission. Collimating structures that enforce the light into desired incident angle of attack onto the reflective filter can be included to enhance the efficiency of the reflective elements in the assembly.

A system and method are disclosed for the detection of water vapor in a natural gas background. The system includes a light source operating in a wavelength range such as, 1.877–1.901 μm, 2.711–2.786 μm, or 920–960 nm, passes through the natural gas to be detected by a detector. In one embodiment, the light source is a tunable diode laser and the moisture level is determined by harmonic spectroscopy. In other embodiments, a VCSEL laser is utilized.

This invention relates to one high speed random wave generator based on FPGA, which adopts DDS technique with data sample rate more than 1GHz and comprises CPU, parallel data phase generation part, wave shape memory part, plug and filter part, parallel and series conversion circuit and DAC, wherein, the parallel data phase generation adopts parallel process to generate multiple data phase In one time clock to get multiple data; then it uses FPGA series and parallel conversion circuit to output the data to DAC into virtual volume.

A pellicle for integrated circuit equipment operating in an EUV range includes a multi-layered structure of alternating layers. The pellicle is constructed and arranged to reflect or absorb undesired radiation and to intercept debris to enhance the spectral purity of a radiation beam.

An optical element including an anti-reflection (AR) coating is configured to reflect Extreme-Ultra-Violet (EUV) radiation only.

A line-narrowed excimer or molecular fluorine laser system includes a discharge chamber filled with a gas mixture at least including molecular fluorine and a buffer gas, multiple electrodes within the discharge chamber connected to a discharge circuit for energizing the gas mixture, a resonator including a pair of resonator reflecting surfaces disposed on either side of the discharge chamber for generating a laser beam, and a line-narrowing / selection unit within the resonator for narrowing the bandwidth of the laser beam. The resonator further includes a third reflecting surface which is deformable and disposed between the pair of resonator reflecting surfaces. The line-narrowing / selection unit preferably includes a beam expander and a dispersive element, wherein the deformable third reflecting surface is disposed between the beam expander and the dispersive element.

The invention discloses a millimeter wave signal photonics generating method based on a highly non-linear optical stimulated Brillouin scattering effect and a millimeter wave signal photonics generating device, and belongs to the technical field of microwave photonics. The device consists of a tunable laser, a first coupler, two parallel Mach - Zehnder modulator, a first DC power supply, the second DC power supply, the third DC power supply, isolators, second coupler, a first photo detector, spectrum analyzers, high nonlinear optical circulator, a second photo detector, microwave amplifiers, intensity modulator, a fourth DC power supply and a microwave signal source. The millimeter wave signal generating device according to the selected output frequency is highly nonlinear optical fiber different in 54GHz to 66GHz. Since the stimulated Brillouin frequency shift value and the wavelength of the pump light of relevant, also can adjust the wavelength tunable laser, millimeter wave signal generator output frequency of the device is adjustable within a certain range.

The invention discloses a wideband multicarrier adaptive radio frequency interference system. The system comprises an operating console, an interference signal source, an interference transmitter, an feed system, a power supply system and the like. The interference method of the system comprises the following steps: a detection receiver inputs the corresponding radio-signal frequencies of the detected target interference frequency band in an interference waveform data generating device; the interference waveform data generating device sets the corresponding interference signal frequency points and generates control information according to the received radio-signal frequency and also generates interference waveform data; then the control information and interference waveform data are transmitted to the interference signal source and processed by a baseband signal source module to generate intermediate frequency analog signals, the analog signals are filtered and transmitted to a converter module, the converter module moves the filtered signals to the corresponding frequency band of radio frequency and then transmits the signals to a power amplifier for power amplification; and then the signals are sent to an antenna through a feeder line and then transmitted to the space for interfering the target signal. The system has high energy utilization rate and can perform continuous interference to the target signal.

The invention provides a tunable all-optical microwave photon frequency conversion device without an external electric local oscillator. The tunable all-optical microwave photon frequency conversion device mainly comprises a narrow line width semiconductor laser unit, a non-linear optical loop circuit, a photoelectric detector and a low-pass filter; a saturated stimulated brillouin scattering effect is stimulated under the condition of not providing the external electric local oscillator and a circuit is selected to transmit by the non-linear optical loop circuit to generate anti-Stokes light for carrying out frequency conversion on a radio-frequency signal. Noise waves and noise inferences, caused by an optical local oscillator in traditional microwave photon frequency conversion are reduced. Meanwhile, the radio-frequency signal is subjected to high-order modulation by using a double-drive lithium niobate modulator, so that the tunable all-optical microwave photon frequency conversion is realized.

The invention discloses a microwave photon up-conversion device and method based on a photoelectric oscillator and belongs to the technical field of microwave photonics. The device is composed of a laser source, a first coupler, a first circulator, a first high nonlinearity dispersion displacement optical fiber, an erbium-doped optical fiber amplifier, a first photoelectric detector, a second coupler, a first Mach-Zehnder modulator, a first microwave signal source, a first direct current voltage-stabilized power supply, an optical filter, a second Mach-Zehnder modulator, a second direct current voltage-stabilized power supply, a second circular, a second high nonlinearity dispersion displacement optical fiber, a second photoelectric detector, a microwave amplifier, a double-parallel Mach-Zehnder modulator, a third direct current voltage-stabilized power supply, a fourth direct current voltage-stabilized power supply, a fifth direct current voltage-stabilized power supply, an optical isolator and a spectrum analyzer. A Brillouin frequency shift value f of the high nonlinearity optical fiber is 9.2GHz, and a signal with frequency of f<m> can be up converted to f<m>+18.4GHz, so alow quality and low frequency intermediate signal is converted into a high quality and high frequency signal.

Provided is a microwave-signal generating method and device based on the excited brillouin scattering effect and the optical frequency comb in high nonlinear fibers. The invention belongs to the technical field of microwave photonics. The device comprises a tunable laser, a first coupler, a second coupler, a first circulator, a second circulator, a first high nonlinear fiber, an attenuator, a fourth coupler, a first photoelectric detector, a power divider, an intensity modulator, a fourth DC voltage regulator, a first double parallel mach-zehnder modulator, a fifth DC voltage regulator, a sixth DC voltage regulator, a seventh DC voltage regulator, a third circulator, a second high nonlinear fiber, a third coupler, a second photoelectric detector, a microwave amplifier, a second double parallel mach-zehnder modulator, a first DC voltage regulator, a second DC voltage regulator, a third DC voltage regulator, an isolator, a fifth coupler, a third photoelectric detector and a frequency analyzer. Due to the advantages of mode selection and positive feedback of a photoelectric oscillator, the microwave signals which are output by the device have the advantages of good spectrum purity and low noises.

The invention discloses a photoelectric oscillator based on an optical resonant cavity, and aims to carry out photoelectric oscillation on laser so as to generate high-quality microwave signals. The photoelectric oscillator consists of a laser, a photoelectric modulator, an amplifier, a filter, a photoelectric detector and an optical resonant cavity which form a loop, wherein the loop forms the main structure of the photoelectric oscillator. The photoelectric oscillator disclosed by the invention has outstanding advantages in generating high-quality microwave signals in a light domain, and high-quality microwave signals can be formed through multiple times of oscillation; the optical resonant cavity is adopted to output the microwave signals through multiple times of oscillation, and the invention mainly aims to minimize the photoelectric oscillator; the optical resonant cavity is adopted to replace conventional long optical fibers, so that the photoelectric oscillator has the characteristics of small size, low consumption, stable performance and the like, and is applicable to the field of radio wireless communication and microwave photonics; the optical resonant cavity is realized through coupled prisms and micro disc cavities and thus is relatively stable in property when being compared with an optical resonant cavity realized through coupled waveguide and micro discs.

The invention provides a dual-mode voltage-controlled oscillator (DMVCO), a frequency synthesizer and a wireless receiving device, and pertains to the technical field of integrated circuit of radio frequency wireless receiver. The DMVCO and the frequency synthesizer can operate in a wideband mode and a quadrature mode. When operating in the quadrature mode, a quadrature signal is provided for a Single Sideband Mixer of the frequency synthesizer by a quadrature coupling of a first voltage-controlled oscillator unit and a second voltage-controlled oscillator unit in the DMVCO in the overlapped frequency band so that the frequency synthesizer can cover a higher output frequency band. Therefore, the tuning range of the DMVCO of the invention is wide, and the frequency synthesizer using the DMVCO is low in power consumption, simple in structure and has good frequency spur performance.

A high power laser system comprising: a master laser; and a primary slave laser oscillator including a cavity comprising a rare earth doped fiber, said primary slave laser oscillator being actively injection-locked to said master laser, wherein said cavity provides an output exceeding 1 W of optical power.

An optical apparatus for illuminating an object, for example an illumination system of a microlithographic exposure system, comprises a light source that generates a plurality of individual bundles that constitute an illumination bundle. A control device controls the light source in such a way that a desired form of the illumination bundle is determined by selecting an appropriate set of individual bundles.

A randomized thermometer-coding digital-to-analog converter (DAC) for the reduction of harmonic distortion due to non-ideal circuit mismatch is presented. The present invention introduces a new dynamic element matching technique that contains three properties of randomization, consecutive selection and less element switching activity to achieve good spurious-free dynamic range and small maximum output error. The topology uses a bank of 1-bit DAC elements, whose outputs are summed to produce a multi-level analog output. The binary digital input is encoded to be thermometer code. During a randomization period, the thermometer code is barrel-shifted to a specific starting position where the position is generated randomly. Thus, the DAC noise is randomized with less element switching activity and consecutive selection.

The invention relates to a frequency synthesis source applied by a DDS short-wave transmitter based on a CPLD design. The frequency synthesis source mainly comprises a direct digital synthesis circuit, a high-speed DAC transformation circuit, a tracking filter circuit and a gain control circuit, a controller and a phase locked crystal oscillator. According to the invention, the high-speed DAC transformation circuit converts frequency data output by direct digital synthesis circuit to a sine frequency signal; and the tracking filter circuit filters components of stray and harmonic wave in the high-speed DAC transformation circuit, and the gain control circuit enables the output of the direct digital synthesis circuit to be stable in amplitude within a frequency range. In addition, the controller comprises a microprocessor and a microcomputer, wherein the microprocessor is connected with the microcomputer through an interface circuit of the microcomputer, and frequency arrangement and transition of working mode are realized by an upper computer. The phase locked crystal oscillator generates a clock source signal with ultrahigh frequency and high stability, and the clock source signal is used as a clock signal of the frequency synthesis source. The frequency synthesis source applied by a DDS short-wave transmitter based on a CPLD design provided in the invention has advantages of high frequency accuracy and high distinguishability, short switching time of frequency signals, constant output amplitude, and simple and high-reliable circuit.

The invention relates to a brand-new full-band frequency generator for a multi-band orthogonal frequency division multiplexing ultrawideband (MB-OFDMUWB). The frequency generator generates all 14 frequencies which meet the requirement of the multi-band orthogonal frequency division multiplexing ultrawideband through a phase-locked loop and a main single sideband (SSB) mixer. The frequency generator generates three frequencies in one band group through one-time main single sideband mixing, the switching between the frequencies in the band group is controlled through an external digital signal, and the switching time of the frequencies depends on the switching time of a switch; and at the same time, the frequencies in different band groups are generated by controlling the frequency dividing ratio of a pre-divider, wherein the center frequencies in the band groups are generated by a local quadrature voltage-controlled oscillator. The full-band frequency generator has a simple structure and small area, saves a large quantity of electric current, can obtain desired frequencies directly through first-stage frequency conversion, and obtains higher spectrum purity.

The invention relates to an oscillator circuit configuration comprising in an LC-parallel oscillatory circuit and a transistor as an amplifying element. A compensating winding is associated with the parallel oscillatory circuit whereby the collector voltage of the transistor is fed to said winding in order to compensate the effect of the parasitic collector capacity. Preferably, the collector current from the transistor is maintained constant be an amplifier.

An apparatus and a method provide synchronization of an output signal to a synchronization information. The synchronization is accomplished by providing coupling of a correction control information that controls a signal generator, e.g. a phase locked loop arrangement or a direct digital synthesis arrangement, to its exact frequency to a frequency conversion unit that converts an uncorrected reference frequency to a correct or exact reference frequency. Thereby, the uncorrected reference frequency for the signal generator can be provided by a simple crystal oscillator without any frequency controller. The setting of the signal generator and the frequency conversion unit can be done in a predetermined sequence which enables a user equipment to synchronize its reference frequency to the synchronization information emitted by a communication network.