Hamamatsu-photonics K.k.

Hamamatsu Photonics Kabushiki Kaisha

Hamamatsu Tv Co, Ltd.

Other

Technology Research Association of Medical and Welfare Apparatus

Hamamatsu Terebi Kabushiki Kaisha

Toshiba Kikai Kabushiki Kaisha

Yutaka Tsuchiya

Shinichiro Aoshima

Hironori Takahashi

Takuya Nakamura

Tsuneyuki Urakami

Musubu Koishi

Katsuyuki Kinoshita

Akira Takeshima

Mitsuharu Miwa

Yutaka Yamashita

Teruo Hiruma

Yoshihiro Takiguchi

Tamiki Takemori

Masatoshi Fujimoto

Yukio Ueda

Isuke Hirano

Eiji Inuzuka

Kazuyoshi Ohta

Makoto Hosoda

Takeshi Kamiya

Takashi Inoue

Kenji Suzuki

Haruyasu Ito

Akira Takahashi

Yoshihiko Mizushima

Motoyuki Watanabe

Takehiro Kurono

Yoshiharu Ooi

Shinji Ohsuka

Harubumi Kato

Yoshinori Inagaki

Katsuo Aizawa

Tamotsu Sasaki

Tooru Hirano

Yoshihiro Hayata

Keiji Kainuma

Atsushi Honma

Yuji Shinoda

Shinichirou Aoshima

Ludwig Schleinkofer

Mutsuji Takahashi

Iakuya Nakamura

Etsuo Tsujimura

Tomoyoshi Hara

The present invention relates to a high-speed particle generating method and so on for generating high-speed particles from a high-speed particle generating target by condensing a pulsed laser beam to a micro-spot on the surface of a high-speed particle generating target. The high-speed particle generating method is a method that generates high-speed particles by condensing a pulsed laser beam generated from a pulsed laser beam generator through an irradiation optical system at a predetermined condensing point, and irradiating the pulsed laser beam to the high-speed particle generating target that is set at the predetermined condensing point, the method including a first step of preparing a reference data, a second step of measuring the wave front of the pulsed laser beam, and a third step of compensating the wave front of the pulsed laser beam based on the reference data.

Method for generating high-speed particle and system for generating high-speed particle

A light pulse from an ultrashort pulse light sourceis split by a beam splitterand guided, to a detection medium, as an excitation pulse and probe pulse having respective predetermined linearly polarized states by an excitation optical systemand probe optical system, respectively. A light track region which is generated in the detection mediumby incidence of the excitation pulse, and in which the refractive index is changed by a nonlinear optical effect, is irradiated with the probe pulse. Of components which have passed through the detection medium, a probe pulse component whose polarized state has changed through the light track region is detected by a cameravia an analyzerin a photodetection part. This realizes a light track observation apparatus capable of directly observing the light track of an excitation pulse.

Light track observing device

A fluorescence component that passes through a region of a detection medium where a change in refractive index has been induced through a nonlinear optical effect produced in the detection medium by a gate pulse is observed as a fluorescence image by utilizing a change in polarization state. By observing the change in position of the fluorescence image while correlating with the change over time in the fluorescence, a fluorescence lifetime measuring apparatus is realized with which the change over time in the fluorescence, in particular the fluorescence lifetime, can be measured efficiently with high temporal resolution.

Instrument for measuring lifetime of fluorescene

A method comprises a first step of dividing a measured medium into N voxels; a second step of assuming an imaginary medium identical to the measured medium except for absence of absorption; a third step of setting a light injection position and a light detection position for the imaginary medium; a fourth step of calculating an impulse response s(t) at the light detection position; a fifth step of calculating a probability density Ui(t',t) that the impulse response at a time t at the light detection position has existed in voxel i (i=1, . . . , N; 1&#x2266;N) at a point of time t&#x2032; (0&#x2266;t&#x2032;&#x2266;t); a sixth step of calculating a cumulative probability Ui(t) that the impulse response detected at the time t has existed in voxel i, from Ui(t&#x2032;,t); and an eighth step of calculating a time-resolved path length li in voxel i from Ui(t) and s(t).

Method of calculating optical path distribution inside scattering absorber

Pulsed light of predetermined wavelengths or modulated light of predetermined frequencies from a light source is injected into a scattering medium as a measured object and output light therefrom is detected by a photodetector . Further, measuring methods and apparatus are configured so as to process and compute internal information by a signal processing unit and an computation processing unit , and the internal information of the scattering medium is obtained by calculating the difference between absorption coefficients by use of the time integrated spectroscopy (TIS method) and the phase modulation spectroscopy (PMS method) based on the MBL law in accordance with a spectroscopy method (MVS method) making use of a mean pathlength and a variance, or physical quantities equivalent thereto. This enables the internal information of the scattering medium to be measured accurately and quickly.

Method and apparatus for measuring internal information of scattering medium

A concentration measuring apparatus for an absorption component in a scattering medium includes a light source ( ) for generating at least two light rays having predetermined wavelengths, the light rays having different transport scattering coefficients for a scattering medium ( ) as an object to be measured, and a known ratio of the transport scattering coefficients; light incidence means ( ) for making the light rays incident from a light incident position into the scattering medium ( ); photodetection means ( ), ( ) for detecting the light ray which has propagated inside the scattering medium ( ) at at least one photodetection position different from the light incident position to acquire at least one photodetection signal; parameter detection means ( ) for detecting, on the basis of the photodetection signal, a light intensity and a mean flight pathlength at the light detection position for each of the at least two light rays having predetermined wavelengths; and arithmetic processing means ( ) for calculating a concentration of an absorption component on the basis of a predetermined relationship between the ratio of the transport scattering coefficients, the light intensity, the mean flight pathlength, and a difference between absorption coefficients per unit concentration of the absorption component for the at least two light rays having predetermined wavelengths.

Concentration measuring method and apparatus for absorption component in scattering medium

A method of measuring an internal property distribution of a scattering medium, comprises a step of injecting rays into a measured medium, a step of detecting rays having passed through the interior of the measured medium, a step of acquiring a measurement value of a predetermined parameter for each of combinations of a light injection position with light detection positions, a step of setting a reference value of an absorption coefficient, a step of acquiring an estimate of the parameter for each of the combinations of the light injection position with the light detection positions, a step of computing a weight function in each voxel, based on the Microscopic Beer-Lambert Law, a step of computing a deviation of the absorption coefficient in each voxel, based on the measurement value and estimate of the parameter, and the weight function, and a step of computing an absolute value of the absorption coefficient in each voxel.

Method and apparatus for measuring internal property distribution in scattering medium

A method characterized by making modulated light having a predetermined modulation frequency component, incident to a scattering medium, receiving the modulated light having propagated inside the scattering medium to acquire measurement signals, detecting signals of the foregoing modulation frequency component from the measurement signals, obtaining amplitudes and inclinations of phase against modulation angular frequency, of the signals of the foregoing modulation frequency component, calculating a difference between absorption coefficients being primary information, based on a predetermined relation among the amplitudes, the inclinations of phase against modulation angular frequency and the difference between absorption coefficients, and calculating a difference of concentration of an absorptive constituent being secondary information, based on the difference between absorption coefficients.

Method and apparatus for measuring absorption information of a scattering medium

Absorption information measuring method and apparatus of scattering medium

A measuring apparatus of absorption information of scattering medium, comprising a light source for generating pulsed light, a light incidence section for making the pulsed light incident to a scattering medium, a light receiving section for receiving the light having propagated inside the measured object, a signal detecting section for temporally cutting a portion out of a light signal obtained by the light receiving section to acquire a measurement signal corresponding to the cut-out signal, a first arithmetic section for performing a measurement for acquiring measurement signals respectively at plural different timings or the like and for deriving a time integration value and a mean optical pathlength for each of the plural measurement signals obtained, and a second arithmetic section for calculating a change amount of concentration of an absorptive constituent, based on a predetermined relation among plural time integration values, plural mean optical pathlengths, an absorption coefficient per unit concentration of the absorptive constituent, and the change amount of concentration of the absorptive constituent.

Measuring method and apparatus of absorption information of scattering

A method for measuring an internal property distribution which includes making measurement light incident from a plurality of light incidence positions on a surface of a measured object, detecting the measurement light that has passed through the object, successively or simultaneously, at at least one light detection position out of a plurality of light detection positions on the surface of the object. A plurality of measurement values obtained by a plurality of combinations of the light incidence position and said light detection position are extracted. A mean value of the measured values are calculated to obtain a reference value and a change amount of a predetermined internal property in each of the plurality of regions of the object are calculated using the plurality of measured values obtained. The reference value thereby establishing an internal property change amount distribution in the object.

Method and apparatus for measuring internal property distribution

Absorption information measuring method and apparatus of scattering

Apparatus for measuring characteristics of a scattering medium. A light source irradiates the medium to be measured with a plurality of measurement light beams. A wavelength selector unit selectively extracts diffused light having a particular wavelength. A photodetector unit measures a time response characteristic of the diffused light. The signal processing system drives the light source so as to sequentially cause measurement light beams to be incident on the scattering medium and controls a measurement action of the photodetector unit while analyzing the time-response characteristics so as to calculate the internal information in the scattering medium.

Measuring the characteristics of a scattering medium

An ultrashort pulse laser apparatus of the this invention includes (1) a laser medium, (2) a laser resonator which stores the laser medium and externally extracts a laser beam, and (3) an excitation source for outputting an excitation energy to the laser resonator to excite the laser medium. The laser resonator includes (i) a plurality of resonant mirrors disposed on both sides of the laser medium to form a resonant optical path, and (ii) a phase dispersion compensation unit which includes two optical members respectively arranged on two light input/output surface sides of the laser medium on the resonant optical path and compensates phase dispersion of light in the resonant optical path. That is, the laser medium is disposed in the optical path between the two optical members of the phase dispersion compensation unit. With this arrangement, even when the laser medium is arranged almost at the center of the laser resonator to stabilize mode locking, the cavity length of the resonant optical path can be reduced. Therefore, the repetition frequency of laser pulses can be increased, and simultaneously, size reduction of the laser apparatus itself can be achieved.

Ultrashort pulse laser apparatus

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Hamamatsu, Japan

Yutaka Tsuchiya