Leland Stanford Junior University

Arizona Board of Regents on Behalf of the University of Arizona

Yao-Te Cheng

Lambertus Hesselink

Yuzuru Takashima

R Fabian W Pease

Max Yuen

Juan R Maldonado

Piero Pianetta

Paul Christopher Hansen

Ludwig Galambos

Yin Yuen

Jason Ryan

Young-Sik Kim

An X-ray grating configured for use in an X-ray imaging apparatus is provided. The X-ray grating has a silicone-based base layer. A plurality of silicon-based ridges is on a surface of the silicon-based base layer, wherein the plurality of silicon-based ridges from a plurality of trenches, where a trench of the plurality of trenches is between two silicon-based ridges of the plurality of silicon-based ridges. A plurality of silicon-based bridges extends between adjacent silicon-based ridges, wherein each silicon-based ridge of the plurality of silicon-based ridges is connected to at least one adjacent silicon-based ridge of the plurality of silicon-based ridges by at least one of a silicon-based bridge of the plurality of silicon-based bridges and wherein at least one of a plurality of four adjacent trenches does not have any silicon-based bridges.

Apparatus with flexible x-ray gratings

Single X-ray grating differential phase contrast (DPC) X-ray imaging is provided by replacing the conventional X-ray source with a photo-emitter X-ray source array (PeXSA), and by replacing the conventional X-ray detector with a photonic-channeled X-ray detector array (PcXDA). These substitutions allow for the elimination of the G0 and G2 amplitude X-ray gratings used in conventional DPC X-ray imaging. Equivalent spatial patterns are formed optically in the PeXSA and the PcXDA. The result is DPC imaging that only has a single X-ray grating (i.e., the G1 X-ray phase grating).

Single X-ray grating X-ray differential phase contrast imaging system

An X-ray detector array includes a scintillator that converts input X-ray radiation to secondary optical radiation output from the scintillator, a first telecentric micro lens array that array receives the secondary optical radiation, a phase coded aperture, where the first telecentric micro lens array directs the secondary optical radiation on the phase coded aperture, a second telecentric micro lens array, where the secondary optical radiation output from the phase coded array is directed to the second telecentric micro lens array, a patterned grating mask, where the second telecentric micro lens array directs the optical beam on the patterned mask, and a photodetector array, where the patterned mask outputs the optical beam in a pattern according to the patterned mask to the photodetector array, where the photodetector array outputs a signal, where a photon fringe pattern is imaged and sampled in the wavelength domain of the radiation from the scintillator.

Photonic-channeled X-ray detector array

A photo-emitter x-ray source is provided that includes a photocathode electron source, a laser light source, where the laser light source illuminates the photocathode electron source to emit electrons, and an X-ray target, where the emitted electrons are focused on the X-ray target, where the X-ray target emits X-rays. The photocathode electron source can include alkali halides (such as CsBr and CsI), semiconductors (such as GaAs, InP), and theses materials modified with rare Earth element (such as Eu) doping, electron beam bombardment, and X-ray irradiation, and has a form factor that includes planar, patterned, or optically patterned. The X-ray target includes a material such as tungsten, copper, rhodium or molybdenum. The laser light source is pulsed or configured by light modulators including acousto-optics, mode-locking, micro-mirror array, and liquid crystals, the photocathode electron source includes a nano-aperture or nano-particle arrays, where the nano-aperture is a C-aperture or a circular aperture.

Photo emitter X-ray source array (PeXSA)

A method of achieving heightened quantum efficiencies and extended photocathode lifetimes is provided that includes using an electron beam bombardment to activate color centers in a CsBr film of a photocathode, and using a laser source for pumping electrons in the color centers of the photocathode.

Enhanced photoelectron sources using electron bombardment

Transmission efficiency and/or spatial resolution provided by resonant apertures can be enhanced by disposing a tip on part of the screen that extends laterally into the aperture. For example, a tip disposed on the ridge of a C-shaped aperture can dramatically improve performance. A spatial resolution of &#x3bb;/50 has been experimentally demonstrated with this approach. The combination of high spatial resolution and high transmission efficiency provided by this approach enables many applications, such as near field optical probes for near field scanning optical microscopy (NSOM). Another application is high resolution electron sources, where an photoelectron emitter can be disposed at or near a tip+aperture structure such that the high resolution optical near-field provides a correspondingly high resolution electron source.

Growing community of inventors

Taipei, Taiwan

Yao-Te Cheng