5 results about "Secondary emission" patented technology

An X-ray source is disclosed, comprising: an electron source configured to provide an electron beam; an aperture configured to limit the angular distribution of the electron beam; a secondary emission limiting aperture configured to limit the angular distribution of the secondary X-ray emission, wherein the electron beam causes secondary X-ray emission to be emitted from a region surrounding the aperture; a first deflector located downstream of the electron beam limiting aperture and configured to deflect the electron beam toward the secondary emission limiting aperture; a target located downstream of the secondary emission limiting aperture and configured to generate primary X-ray emission through interaction with the electron beam; and an exit window located to transmit the primary X-ray emission, wherein the secondary emission is prevented from reaching the exit window by the secondary emission limiting aperture. A corresponding method is also disclosed.

The invention belongs to the field of optical fiber communication, and discloses a dispersion simulation transmission link based on analog signal processing and a dispersion simulation method, and the dispersion simulation transmission link comprises a coherent transmitter, an IQ modulator, lasers with different wavelengths, a coherent receiving chip (ICR), a Bragg dispersion compensation grating (FBG-DCM) and a coherent receiver. Data is sent out from a coherent transmitter, firstly passes through an ICR, a light field is converted into an electric field, and the electric field is modulated into a new light field by an IQ modulator. Two paths can be selected at the output end of the ICR, the first path is connected to the IQ modulator and is subjected to secondary emission by utilizing intrinsic light with different wavelengths, the wavelength can be converted to an FBG-DCM compensation window, and after the steps, the ICR is used for receiving and then is converted to the original wavelength by utilizing the IQ modulator to be sent, so that the superposition of negative dispersion is realized; and the second path is connected to the IQ modulator, secondary emission is carried out by utilizing intrinsic light with different wavelengths, phase conjugation is realized, meanwhile, conversion to an FBG-DCM compensation window is realized, and superposition of positive dispersion is realized through the above steps after ICR receiving.

The application belongs to the field of optical fiber communication, and discloses a dispersion simulation transmission link and a dispersion simulation method based on analog signal processing. The dispersion simulation transmission link comprises a coherent transmitter, an IQ modulator, lasers with different wavelengths, an interference receiving chip (ICR), a Bragg dispersion compensation grating (FBG-DCM) and a coherent receiver. Data is sent from the coherent transmitter, first passes through the ICR to convert the optical field into the electrical domain, and is modulated into a new optical field by the IQ modulator. The output end of the ICR has two optional paths. The first path is connected to the IQ modulator, uses the secondary emission of intrinsic light with different wavelengths, and converts the wavelength to the FBG-DCM compensation window. After the above steps, the original wavelength is converted by the IQ modulator after being received by the ICR for transmission, so that the superposition of negative dispersion is realized. The second path is connected to the IQ modulator, uses the secondary emission of intrinsic light with different wavelengths, realizes the phase conjugation and converts to the FBG-DCM compensation window at the same time. After the above steps, the ICR receives and realizes the superposition of positive dispersion.

It is disclosed to determine changes in charged particle beam (CPB) source position by scanning an alignment aperture, particularly at the edge of a defocussed CPB illumination disk, the alignment aperture being fixed relative to a beam defining aperture in the CPB. The alignment aperture is operable to transmit a portion of the CPB to a secondary emission surface which generates a secondary emission directed to a scintillator element. Scintillating light generated in response is directed by a light guide out of a vacuum housing associated with the CPB to an external photodetection system.

Lighting equipment (1) comprising: a light source (10) for emitting light, in particular a light-emitting diode, and an optical element (100) for reducing the divergence and changing the direction of the light emitted by the light source, wherein the optical element (100) has a light entry surface (110) for coupling in the light emitted by the light source and a light exit surface (120) for coupling out the coupled-in light, wherein the light emitted by the light source has a primary emission characteristic and the light coupled out of the optical element has a secondary emission characteristic, and wherein the secondary emission characteristic has a emission angle (β) which is smaller than the emission angle (α) of the primary emission characteristic in order to reduce the divergence of the light emitted by the light source, and wherein the optical axis of the light-exit surface (120) is inclined to the optical axis of the light-intake surface (110) in order to change the direction of the light emitted by the light source, and wherein the optical element comprises a plurality of light-guiding elements (200) which each form a part of the light-entry surface (110) and a part of the light-emission surface (120) of the optical element (100) and each comprise an interface (210) extending between the light-entry surface and the light-emission surface for reflection, in particular total internal reflection at this interface (210), of the coupled-in light, wherein the plurality of light-guiding elements (200) are designed as interconnected, in particular fused, individual fibers in a common drawing process, and wherein the light guiding elements each have a cross-section at the light exit surface (120) which is larger than the cross-section at the light entry surface (110), in particular such that the light exit surface (120) of the optical element is larger than the light entry surface (110) of the optical element, and wherein the optical element comprises a widening section (130) within which the cross-section of the light-guiding elements and / or the cross-section of the optical element increases and wherein the optical element has a curvature section (140) within which the optical axis of the optical element is curved, wherein the widening section (130) and the curvature section (140) are arranged apart from each other along the optical axis, such that the widening section (130) is located closer to the light entry surface and the curvature section (140) is located closer to the light exit surface.