Hamamatsu-photonics K.k.

Nippon Telegraph and Telephone Corporation

Japan Science and Technology Agency

Ntt Advanced Technology Corporation

Masatoshi Fujimoto

Shinichiro Aoshima

Hironori Takahashi

Yoichi Kawada

Makoto Hosoda

Yutaka Tsuchiya

Koei Yamamoto

Hidenao Iwai

Shingo Oishi

Kodai Fukazawa

Kenshi Fukumitsu

Tomofumi Suzuki

Takashi Sakamoto

Mitsuhito Mase

Kazuo Fujiura

Seiji Toyoda

Haruyasu Ito

Akira Takahashi

Atsushi Nakanishi

Takashi Yasuda

Hiroshi Kumagai

Shogo Yagi

Katsumi Midorikawa

Tadashi Sakamoto

Shigeru Sakamoto

Joji Yamaguchi

Yuzo Sasaki

Hiroshi Saito

Koji Yoneyama

Eiichi Sugai

Shogo Yamagishi

Toshiharu Moriguchi

Yukihiko Ushiyama

Mahiro Yamada

Shin-Ichiro Aoshima

Kazutaka Tomari

Takayoshi Kuga

An optical coherence tomography device includes a light source, a mirror device including a movable mirror configured to perform a reciprocating operation, a support part configured to support an object, a beam splitter configured to generate interfering light, an optical sensor configured to detect the interfering light, and a control unit. Each of the plurality of pixels included in the optical sensor includes a light receiving part, a plurality of transfer gates, and a discharge gate. The control unit applies an electric signal to the optical sensor so that the plurality of transfer gates are sequentially brought into a charge transfer state in at least three time ranges separated from each other and the discharge gate is brought into a charge discharge state in a time range other than the at least three time ranges for each period of an interferogram signal of the interfering light.

Optical coherence tomography device

The device includes a spatial light modulation section having a phase modulation plane to which laser light Lin a wavelength region longer than an ultraviolet region is input, and on which a phase of the laser light Lis modulated at each of a plurality of two-dimensionally arrayed regions, to generate modulated laser light L, a wavelength conversion section having a light incident plane which receives the modulated laser light Loutput from the spatial light modulation section, and converting a wavelength of the modulated laser light Linto a wavelength in the ultraviolet region, and an image transfer optical system coupling the phase modulation plane of the spatial light modulation section and the light incident plane of the wavelength conversion section, so as to be optically conjugate systems to each other.

Wavelength conversion-type spatial light modulation device

Provided is a swept light source including one end surface coupled to a wavelength filter constituted of a diffraction grating and an end mirror via a light deflector and another end surface including a gain medium facing an output coupling mirror and which configures a laser cavity between the end mirror and the output coupling mirror, wherein a drive voltage having an AC voltage on which a DC bias voltage is superimposed is output from a control voltage source of the light deflector to an electrode pair of an electro-optic crystal, light is radiated from a light emitter to the electro-optic crystal, and incident light from the gain medium incident along an optical axis perpendicular to a direction of an electric field formed by the control voltage is deflected in a direction parallel to the electric field, so that wavelength sweeping is performed.

Swept light source and method for controlling the same

A driving circuit is a circuit selectively outputting one of a staircase wave and a square wave from an output terminal, to drive a capacitive load, and includes a first power source supplying a constant voltage VH, a first FET connected between the output terminal and the first power source, a first transformer in which an output side coil is connected to a gate of the first FET, a first input terminal connected to an input side coil of the first transformer via a capacitive element, a second power source supplying a constant voltage VL, a second FET connected between the output terminal and the second power source, a second transformer in which an output side coil is connected to a gate of the second FET, and a second input terminal connected to an input side coil of the second transformer via a capacitive element.

Capacitive load driving circuit

Provided is an observation device which can obtain a phase image of a moving object rapidly with high sensitivity even when using a photodetector having a slow read-out speed per pixel. The observation devicecomprises a light source, a first modulator, a second modulator, a lens, a beam splitter, a photodetector, and an arithmetic unit. The lensreceives scattered light generated by a moving objectand forms a Fourier transform image of the object. The photodetectoroutputs data representing a sum in a v direction of data temporally changing at a frequency corresponding to a Doppler shift frequency of the light having reached each position on a light-receiving surface through the lensat each position in a u direction at each time. The arithmetic unitobtains an image of the objectaccording to the output of the photodetector

Phase image acquisition device

The present invention provides an optical amplifying device which can be easily downsized, increased in output, and stabilized. An optical amplifying deviceA includes an optical amplifierA and an energy supplier. The optical amplifierA includes an optical amplifying mediumand a transparent medium. The energy suppliersupplies excitation energy (for example, excitation light) to the optical amplifying medium. The optical amplifying mediumis supplied with the excitation light to amplify light and output it. To-be-amplified light passes through the transparent mediumin the optical amplifying mediuma plurality of times. The transparent mediumcan propagate the to-be-amplified light, for example, zigzag inside.

Optical amplifying device

An input light pulse Pi, input at a constant incident angle to a transmission-type diffraction grating, is dispersed according to the wavelengths to be output at output angles according to the wavelengths, to be reflected by reflecting mirrors, andin series, and thereafter, the light rays are input at incident angles according to their wavelengths to the transmission-type diffraction grating, to be output at a constant output angle from the transmission-type diffraction grating. The optical path for the light rays of respective wavelength components, output at the constant output angle from the transmission-type diffraction grating, is folded back by a rectangular prism, to be input at a constant incident angle to the transmission-type diffraction grating, and the light rays are output at output angles according to their wavelengths, to be reflected by the reflecting mirrors, andin series, and are thereafter input at incident angles according to their wavelengths to the transmission-type diffraction grating. The light rays, input at the incident angles according to their wavelengths to the transmission-type diffraction grating, are coupled by the transmission-type diffraction grating, to be output as an output light pulse Po. Thereby, realizing the pulse width conversion device and the optical amplifier system, which are easily downsized.

Pulse-width converting apparatus and optical amplifying system

A pulse fiber laser devicehas a Fabry-Perot type optical resonator, and is provided with an excitation light source, an optical coupling unit, an amplifying optical fiber, a saturable absorber, a gradient index lens, an optical output unit, a dispersion adjusting unit, a mirrorand a mirror. The saturable absorberand the mirror, integrated into one body, constitute a saturable absorber mirror. The gradient index lensconverges the light output from an end face of an optical fiberand outputs the light to the saturable absorber mirror, and inputs the light reflected from the saturable absorber mirrorinto the end face of the optical fiber. Thus, there is provided a pulse fiber laser device that enables easy adjustment of the intensity of light incident on a saturable absorber and facilitates miniaturization.

Pulse fiber laser device

A total reflection terahertz wave measuring apparatusincludes a light source, a branching part, a chopper, an optical path length difference adjusting part, a polarizer, a beam splitter, a terahertz wave generating element, a filter, an internal total reflection prism, a terahertz wave detecting element, a &#xbc; wavelength plate, a polarization split element, a photodetector, a photodetector, a differential amplifier, and a lock-in amplifier. The internal total reflection prismis a so-called aplanatic prism, and has an entrance surface, an exit surface, and a reflection surface. The terahertz wave generating elementand the filterare provided to be integrated with the entrance surfaceof the internal total reflection prism, and the terahertz wave detecting elementis provided to be integrated with the exit surfaceof the internal total reflection prism. The filterallows a terahertz wave to be transmitted therethrough and blocks pump light. Accordingly, a total reflection terahertz wave measuring apparatus, which can be downsized, can be realized.

Total reflection terahertz wave measurement device

A laser beam emitted from a laser source is projected onto a target set in a vacuum chamber while being focused by a focusing optical system. This results in generating fast particles, such as protons and emitting the particles from the target. A light measuring device measures plasma emission from the target upon in-focus irradiation with the laser beam and an analyzing device analyzes a measurement signal therefrom to assess a generation state of fast particles. Then the focusing optical system and target are controlled through optical system moving mechanism and target moving mechanism on the basis of the result of the analysis and feedback control is performed on the generation state of fast particles in the target. This realizes a fast particle generating apparatus capable of monitoring the generation state of fast particles in real time and thereby efficiently generating the fast particles.

Fast particle generating apparatus

In an imaging apparatus, a detection sectiondetects a beam Lhaving passed through an aperturein a first direction and a location designation beam Lhaving passed through the aperturein the opposite direction is made incident to a position (x,y) in a first light image IMon an image pickup surface corresponding to a specific position (x,y) in a second light image IMwhereby the result of detection of the beam Ldetected at the detection sectionindicates data at a specific position in an incoming light image designated by the location designation beam L, regardless of whether there is a mechanical error in movement of the aperture

Image pickup device

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

The transparent medium processing device comprises: a light control section for performing variable control for the status of the laser beam emitted from the light source section , and a light status measurement section for measuring the status of the laser beam inside the processing target TG. The light control section is adjusted based on the output of the light status measurement section so that the status of the laser beam inside the processing target becomes a desired status. Since the status of the laser beam inside the processing target, which is made of such a transparent medium as glass, is measured by the light status measurement section, and is fed back to the light control section, laser processing can be executed while maintaining an optimum status at a processing point inside the processing target.

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Hamamatsu, Japan

Masatoshi Fujimoto