University of Hyogo

Hyogo Prefectural Government

Kunihiro Sato

Kensaku Shimoda

The present invention provides a holographic imaging device and a holographic imaging method that have improved performance in which the influence of a refractive index of a cube-type beam coupler constituting an optical system is considered. The holographic imaging devicecomprises the beam couplerconsisting of the cube-type beam splitter arranged between the objectand the image sensorand the calculation reference light hologram generation unitfor generating an inline reference light hologram jrepresenting a light wave on the hologram planeby performing a light wave propagation calculation including propagation inside the beam coupler, on a spherical wave emitted from the condensing point Pof the inline spherical wave reference light L. The inline reference light hologram jis a computer-generated hologram and used for generating an object light hologram g by removing component of the reference light L from a complex-amplitude inline hologram Jrepresenting the object light O and the inline spherical wave reference light L on the hologram plane

Holographic imaging device and holographic imaging method

A holographic imaging device and method realizes both a transmission type and a reflection type, and also realizes a long working distance wide field of view or ultra-high resolution. Object light emitted from an object, sequentially illuminated with parallel illumination light whose incident direction is changed, is recorded on a plurality of object light holograms for each incident direction using off-axis spherical wave reference light. The reference light is recorded on a reference light hologram using in-line spherical wave reference light being in-line with the object light. An object light wave hologram and its spatial frequency spectrum at the object position are generated for each incident direction using each hologram. A synthetic spectrum which occupies a wider frequency space is generated by matching each spectrum in the overlapping area, and a synthetic object light wave hologram with increased numerical aperture is obtained thereby.

Holographic imaging device and data processing method therefor

The illumination light condensing point Pand the reference light condensing point Pare arranged as mirror images of each other with respect to the virtual plane VP, and each data of the object light O, being a reflected light of the spherical wave illumination light Q, and the inline spherical wave reference light L is recorded on each hologram. On the virtual plane VP, the reconstructed object light hologram hfor measurement is generated, and the spherical wave optical hologram srepresenting a spherical wave light emitted from the reference light condensing point Pis analytically generated. The height distribution of the surface to be measured of the object 4 is obtained from the phase distribution obtained by dividing the reconstructed object light hologram hby the spherical wave light hologram s.

Surface shape measurement device and surface shape measurement method

The present invention provides an ellipsometry device and an ellipsometry method whereby measurement efficiency can be enhanced. In this method, an object is illuminated by spherical-wave-like illumination light Q linearly polarized at 45&#xb0; (S), and an object light O, being a reflected light, is acquired in a hologram Iusing a spherical-wave-like reference light R having a condensing point near the condensing point of the illumination light Q, and a hologram Iof the reference light R is furthermore acquired using a spherical-wave reference light L having the same condensing point as that of the illumination light Q (S). The holograms are separated into p- and s-polarized light holograms I, I, &#x3ba;=p, s and processed to extract object light waves, and object light spatial frequency spectra G(u, v), &#x3ba;=p, s are generated (S) (S). Ellipsometric angles &#x3c8;(&#x3b8;), &#x394;(&#x3b8;) are obtained for each incident angle &#x3b8; from the amplitude reflection coefficient ratio &#x3c1;=G/G=tan &#x3c8;&#xb7;exp(i&#x394;). Through use of numerous lights having different incident angles &#x3b8; included in the illumination light Q, data of numerous reflection lights can be acquired collectively in a hologram and can be processed.

Ellipsometry device and ellipsometry method

An interference fringe pattern (I) between an inline spherical wave light (L) and an off-axis reference light (R) is recorded with a photo detector (), and on which spatial-frequency filtering is applied to obtain a complex amplitude in-line hologram (J). A complex amplitude off-axis hologram (J) is derived by performing a spatial frequency filtering on a hologram (I) in which an object light (O) emitted from a microscopic subject illuminated with a spherical wave light (L) is recorded with a reference light (R), and the derived data is divided with data of the hologram (J) so that a complex amplitude in-line hologram (J) from which a component of the reference light (R) is eliminated is generated and recorded.

Holographic microscope, microscopic subject hologram image recording method, method of creation of hologram for reproduction of high-resolution image, and method for reproduction of image

The present invention can realize both a transmission type and a reflection type, and provides a holographic microscope which can exceed the resolution of the conventional optical microscope, a hologram data acquisition method for a high-resolution image, and a high-resolution hologram image reconstruction method. In-line spherical wave reference light (L) is recorded in a hologram (I) using spherical wave reference light (R), and an object light (O) and an illumination light (Q) are recorded in a hologram (I) using a spherical wave reference light (R) by illuminating the object with an illumination light (Q, j=1, . . . , N) which is changed its incident direction. From those holograms, a hologram (J), from which the component of the reference light (R) is removed, is generated, and from the hologram, a light wave (h) is generated. A light wave (c) of the illumination light (Q) is separated from the light wave (h), and using its phase component (&#x3be;=c/|c|), a phase adjustment reconstruction light wave is derived and added up as (H=&#x3a3;h/&#x3be;), and an object image (S=|H|) is reconstructed.

Holographic microscope and data processing method for high-resolution hologram image

The present method includes a data acquisition process and tomographic image generation processes. In the data acquisition process, holograms of an object light and so forth are acquired for each light with a wavelength by changing the wavelengths of the illumination light, off-axis spherical wave reference light, and inline spherical wave reference light. In the tomographic image generation process, a reconstructed light wave of the object light and a reconstructed light wave of the illumination light on a reconstruction surface are generated from these holograms. A reconstruction light wave with adjusted phase is added up for each wavelength to generate a tomographic hologram. From this, an accurate and focused tomographic image without distortion can be generated.

Holographic microscope, holographic image generation method, and method for acquiring data for holographic image

This three-dimensional shape measurement method comprises: a projection step for projecting an interference fringe pattern (F) having a single spatial frequency (fi) onto an object surface; a recording step for recording the pattern (F) as a digital hologram; and a measurement step for generating a plurality of reconstructed images having different focal distances from the hologram, and deriving the distance to each point on the object surface by applying a focusing method to the pattern (F) on each of the reconstructed images. The measurement step extracts the component of the single spatial frequency (fi) corresponding to the pattern (F) from each of the reconstructed images by spatial frequency filtering, upon applying the focusing method, and makes it possible to achieve a highly accurate measurement in which the adverse effect of speckles is reduced and the advantage of a free-focus image reconstruction with holography is used effectively.

Three-dimensional shape measurement method and three-dimensional shape measurement device

A method for generating a complex amplitude in-line hologram and an image recording device using said method makes it possible to realize high-speed processing and high-speed recording from a single off-axis hologram without limiting the spatial frequency band and without creating errors from interpolation. The complex amplitude in-line hologram is generated by performing the following in order: the acquisition of data for one off-axis hologram obtained by way of off-axis holography, and for an off-axis reference light used for obtaining the hologram; the setting of a reconstruction in-line reference light; a modulation process for performing spatial heterodyne modulation on the hologram on the basis of the phases of the reference lights; and a filtering process for performing spatial frequency filtering on the hologram modulated by the modulation process. Because spatial sampling is not performed, the limits on the viewing angle are relaxed.

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Himeji, Japan

Kunihiro Sato