Canon Kabushiki Kaisha

Chidane Ouchi

Toru Den

Seima Kato

Kentaro Nagai

Hidenosuke Itoh

Akihiro Nakauchi

Naoki Kohara

Masanobu Hasegawa

Naoto Sano

Takao Ukaji

Yuzo Seo

Kimiaki Yamaguchi

Toshiyuki Naoi

There is provided an X-ray imaging apparatus which images a specimen. The X-ray imaging apparatus comprises: an X-ray source; a diffraction grating configured to diffract an X-ray from the X-ray source; an X-ray detector configured to detect the X-ray diffracted by the diffraction grating; and a calculator configured to calculate phase information of the specimen on the basis of an intensity distribution of the X-ray detected by the X-ray detector, wherein the calculator obtains a spatial frequency spectrum from the plural intensity distributions, and calculates the phase information from the obtained spatial frequency spectrum.

X-ray imaging apparatus and wavefront measuring apparatus

An X-ray imaging apparatus comprises a grating configured to form an interference pattern by diffracting X-rays from an X-ray source, a amplitude grating configured to partly shield X-rays forming the interference pattern, and an X-ray detector configured to detect an intensity distribution of X-rays from the amplitude grating. The amplitude grating is comprised of a central area and a peripheral area and the peripheral area shows an X-ray transmittance higher than the central area relative to X-rays perpendicularly entering the amplitude grating.

X-ray imaging apparatus

An X-ray imaging apparatus for imaging a subject includes a diffraction grating configured to form an interference pattern by diffracting X-ray radiation from an X-ray source, a shielding grating configured to shield part of the interference pattern, a detector configured to detect the X-ray radiation passing through the shielding grating, and a moving unit configured to change an angle between each of the diffraction grating, the shielding grating and the detector and an optical axis, wherein the detector is configured to detect the X-ray according to a change in the angle between each of the diffraction grating, the shielding grating and the detector and the optical axis.

Provided is an X-ray imaging apparatus having simple configuration and obtaining differential phase contrast images in two directions crossing each other without rotating the diffraction grating and the masking grating. The apparatus including: a diffraction grating diffracting X-rays; a masking grating masking portions rays and transmitting portions are two-dimensionally arranged to partially mask bright zones of the interference pattern; a moving device changing the relative position between the interference pattern and the masking grating; a detector detecting the intensity distribution of the X-rays transmitted through the masking grating; and a calculator calculating a differential phase contrast image or a phase contrast image of a subject, the calculator being configured to calculate the differential phase contrast image or the phase contrast image in each of two mutually crossing directions on the basis of results of detection performed a plurality of times by the detector.

An absolute position measurement apparatus measures an absolute position of an object to be measured using a first light source and a second light source which has coherency lower than that of the first light source. The absolute position measurement apparatus includes a measurement part which measures a point where phases of interference signals from the first and the second light sources coincide with each other or a point where an intensity of the interference signal from the second light source is maximized, an origin defining part which defines the point measured by the measurement part as an origin position, a phase storing part which stores the phase of the interference signal from the first light source at the origin position, an origin redefining part which redefines the origin position, and a position calculating part which calculates the absolute position of the object to be measured.

Absolute position measurement apparatus and method

An X-ray imaging apparatus which takes an image of an object to be detected, comprises: a first grating to form a periodic bright-dark pattern by a Talbot effect, based on an X-ray from an X-ray source; a second grating, disposed at a position where the bright-dark pattern is formed, to block a part of the bright-dark pattern; a detector to detect an X-ray intensity distribution of the X-ray which passed through the second grating; and a calculator to calculate phase information of the X-ray based on the detected X-ray intensity distribution, wherein the second grating includes a first region having a first blocking pattern and a second region having a second blocking pattern, and a direction in which the first blocking pattern blocks a bright section of the bright-dark pattern is different from a direction in which the second blocking pattern blocks the bright section of the bright-dark pattern.

An imaging apparatus analyzes a periodic pattern of a Moir&#xe9; due to Talbot interference by the Fourier transform method and forms an image. The imaging apparatus includes a first grating having a structure that transmits light beams from a beam source to refract or diffract the light beams and forms a self image based on a first periodic pattern by the Talbot interference at a predetermined position; a second grating that absorbs part of the first periodic pattern and causes a Moir&#xe9; to be generated based on a second periodic pattern when the second grating is arranged at a position at which the self image is formed. All cross sections of the Moir&#xe9; with axes in differential directions of a wavefront for the analysis by the Fourier transform method have a two-dimensional periodic structure in which periods of patterns in the second periodic pattern are the same.

Imaging apparatus and imaging method

An X-ray imaging apparatus includes a phase grating, an absorption grating, a detector, and an arithmetic unit. The arithmetic unit executes a Fourier transform step of performing Fourier transform for an intensity distribution of a Moir&#xe9; acquired by the detector, and acquiring a spatial frequency spectrum. Also, the arithmetic unit executes a phase retrieval step of separating a spectrum corresponding to a carrier frequency from a spatial frequency spectrum acquired in the Fourier transform step, performing inverse Fourier transform for the separated spectrum, and acquiring a differential phase image.

X-ray imaging apparatus, X-ray imaging method, and X-ray imaging program

A Talbot interferometer includes a diffraction grating, an image pickup device, a moving unit configured to move at least one of the diffraction grating and the image pickup device in an optical axis direction of the test object, and a computer configured to adjust a position of the at least one of the diffraction grating and the image pickup device using the moving unit so that a Talbot condition can be met, based on a spatial frequency spectrum obtained from a plurality of interference fringes captured by the image pickup device while moving the at least one of the diffraction grating and the image pickup device using the moving unit.

Talbot interferometer, its adjustment method, and measurement method

A wavefront-aberration-measuring device measures wavefront aberration of a to-be-tested optical system and includes a diffraction grating that splits light transmitted through the optical system, a detecting unit that detects interference fringes produced by beams of the split light, an arithmetic unit that calculates the wavefront aberration from the detected interference fringes, an image-side mask insertable into and retractable from an image plane of the optical system, and an illuminating unit that incoherently illuminates the image-side mask. The image-side mask has an aperture with a diameter larger than &#x3bb;/2NA, where &#x3bb; denotes a wavelength of the illuminating unit and NA denotes a numerical aperture of the to-be-tested optical system. The arithmetic unit calculates the wavefront aberration of the optical system from the interference fringes detected with the image-side mask being retracted from the image plane and the interference fringes detected with the image-side mask being in the image plane.

Wavefront-aberration-measuring device and exposure apparatus

A wavefront aberration measuring device includes a mask placed in an object plane of a to-be-tested optical system and having a pattern including a pinhole producing a spherical wave and adjoining diffraction gratings each ruled with lines oriented in a direction different from the other; an illumination optical system that illuminates an area of the mask with light emitted from a light source; a light splitter that splits the light from the pattern transmitted through the to-be-tested optical system; an image pickup unit that takes an image of interference fringes produced by the split light, the image being used in measuring wavefront aberration of the to-be-tested optical system; a detector that detects respective light quantities of respective diffracted beams from the respective illuminated diffraction gratings; and a control unit that controls alignment of the illuminated area of the mask and the pattern in accordance with a detection result.

Wavefront aberration measuring method, mask, wavefront aberration measuring device, exposure apparatus, and device manufacturing method

A measuring apparatus includes a pinhole mask, located on an object plane of an optical system to be measured, and having a plurality of pinholes for generating a spherical wave from a measuring light beam, and a diffraction grating for splitting the measuring light beam that has passed the pinhole mask and the optical system, in which Lg=m&#xb7;Pg/&#x3bb; is met, where Pg is a grating pitch of the diffraction grating, &#x3bb; is a wavelength of the measuring light beam, m is an integer other than zero, and Lg is a distance between the diffraction grating and an image plane of the optical system. The measuring apparatus detects an interferogram formed by interference between a plurality of the measuring light beams split by the diffraction grating. The plurality of measuring light beams includes an aberration of the optical system.

Measuring apparatus, exposure apparatus and method, and device manufacturing method

A measurement apparatus includes a first mask that is arranged on an object plane of a target optical system, and has a window that transmits measurement light, a second mask that has a reflection surface for reducing coherence of the measurement light, and a diffraction grating configured to split the measurement light that has been reflected on the second mask, has passed the first mask and the target optical system, wherein a distance Lg between the diffraction grating and an image plane of the target optical system satisfies Lg=m&#xb7;Pg/&#x3bb; where Pg is a grating pitch of the diffraction grating, &#x3bb; is a wavelength of the measurement light, and m is an integer except for 0.

Growing community of inventors

Utsunomiya, Japan

Chidane Ouchi