Cyber Laser Inc.

Nec Corporation

Hitoshi Sekita

Kazuya Takasago

Tetsumi Sumiyoshi

Taisuke Miura

Yusuke Tamaki

Akira Watanabe

Tadashi Okuno

Tadashi Kasamatsu

Nobuo Nakata

Hiroshi Tsugita

Akira Shiratori

Arata Nakamura

A problem diagnosis method and problem repair method for a laser device are provided. The method includes measuring the intensity of scattered light generated by an optical part inside the laser device; referring to data indicating a temporal change in the scattered light predicted under predetermined operating conditions of the laser device, and predicting the seriousness of the problem from the intensity of scattered light; and determining what kind of maintenance work is necessary based on the seriousness of the problem. Additionally, the seriousness of the problem in the optical part can be predicted by executing fuzzy logic based on membership functions defining the relationship between scattered light intensity and the seriousness of problems of optical parts.

Problem diagnosis method and problem repair method for laser device

A femtosecond laser with stabilized output, and a method for stabilizing the output of a femtosecond laser. The femtosecond laser comprises a regenerative amplifier, a photodetector, a control portion and a variable attenuator, wherein the variable attenuator is provided so as to be capable of controlling an output beam of the regenerative amplifier, the photodetector is provided between the regenerative amplifier and the variable attenuator, the photodetector detects an output beam of the regenerative amplifier and transmits the results of the detection to a power controller, and the power controller controls the variable attenuator depending on the a difference between a predetermined target value and the results.

Femtosecond laser device having output stabilizing mechanism

The present invention offers a laser oscillator device having sufficient cooling ability to maintain a lasing medium which generates high-density thermal energy at a temperature appropriate for use, while being capable of being made compact. The laser oscillator device comprises an excitation beam source for generating an excitation beam, a laser medium for receiving the excitation beam and performing optical amplification, a laser oscillator device for causing resonance of light emitted by the laser medium for laser oscillation, and a cooling system for cooling said laser medium, wherein the cooling system uses a gas as the heat-carrying medium.

Helium-cooled laser device

The present invention has the object of offering a laser resonator capable of maintaining high amplification efficiency even if the thermal lensing effect occurring in the laser medium varies during operation or over repeated operation and suspension of the laser device. The laser resonator comprises at least a pair of reflection portions (planar reflective mirrors) provided such as to allow a laser beam to oscillate therebetween; a laser medium provided on the optical path of the laser between the pair of reflection portions; an excitation portion (excitation laser device) for exciting the laser medium; an optical system (convex lens) provided on the optical path of the laser beam between the laser medium and the pair of reflection portions for changing the state of the laser in the laser medium; and a movement portion for moving the optical system along the optical axis of the laser.

Laser resonator and adjustment method

The invention offers a regenerative optical amplifier enabling voltage to be easily applied to polarizing elements such as Pockels cells, without the need for complicated drive circuitry. An input beam of S-polarized light is reflected by a polarizerand advances to a Pockels cell. In the time it takes for the input beam, having once passed through the Pockels cell, to be reflected by a reflective mirrorand return to the Pockels cell, a voltage Vcausing a 90-degree rotation in the polarization of transmitted light is applied to the Pockels cell, and this applied voltage Vis maintained. The input beam is converted by the Pockels cellinto a P-polarized light pulse which is transmitted by the polarizer. Subsequently, the light pulse is converted from P-polarized light to S-polarized light and back to P-polarized light with each roundtrip of the Pockels cell, while passing each time between the reflective mirror, laser crystaland reflective mirror, so as to be amplified in the resonator formed thereby. The amplified light pulse is extracted by applying a voltage Vcausing a 90-degree rotation of the polarization of the transmitted light to the Pockels cellto convert the light pulse to S-polarized light which is then reflected out of the resonator by the polarizer

Regenerative optical amplifier

The invention offers a low-noise, compact, high-efficiency light generating device and an irradiation method thereof for use in medical applications. A fundamental harmonic laser head is composed of a quasi-continuous wave oscillation mode laser diode (QCW-LD) a laser crystal a rear mirror and an output mirror The QCW-LD is driven by an LD power source capable of modulating the pulse waveform in time. A beam adjusting portion comprises a wave plate, a polarizer, a lens and an isolator. A wavelength converting portion is an optical parametric oscillator (OPO) comprising a non-linear optical crystal an OPO input mirror and an OPO output mirror

Light generating device and laser device using said light generating device

A laser radiation device comprises a pumping light emission section, a fiber laser device and a beam guiding section. The pumping light emission section generates and emits pumping light. In the fiber laser device, an optical fiber doped with laser ions is excited by the pumping light and thereby a laser beam including two or more wavelength components is generated. The beam guiding section guides the laser beam into desired place and direction. The laser beam including the two or more wavelength components having characteristic effects are focused by a beam shaping section and applied to the surface of an object. When holmium ions are doped in the optical fiber of the fiber laser device as the laser ions, a laser beam including a 3 &mgr;m band component (which is suitable for precise incision of a living body) and a 2 &mgr;m band component (which is suitable for tissue coagulation and hemostasis) is emitted by the fiber laser device, and the two wavelength components are applied to the surface of the object maintaining coaxiality, thereby the two effects of the two wavelength components are attained simultaneously on the object. The laser radiation device including only one laser device can be implemented with low manufacturing cost and in a small size.

Laser radiation device employing a fiber laser capable of emitting a laser beam including two or more wavelength components

In a quasi-three-level solid-state laser that is excited by a semiconductor laser, a temperature-controlling apparatus is used to operate the crystal temperature that enables optimum laser operation in terms of both efficiency and output, based on the effect that cooling the crystal has on reducing the efficiency of absorption of power from the semiconductor excitation laser and the effect that cooling the crystal has on lowering the oscillation threshold value.

Growing community of inventors

Tokyo, Japan

Hitoshi Sekita