A laser light source unit for vehicles is provided, having a resonator containing a first end mirror and a second end mirror and an active laser medium in between. The laser light source unit has a pump device for generating a pump radiation into the resonator. The pump radiation is configured such that laser light of the first wavelength, a second wavelength, and/or a third wavelength can be radiated. An intermediate mirror is configured so that the radiation of the second wavelength is reflected, and the radiation of the third wavelength is transmitted. A third end mirror is configured so that the radiation of the second wavelength is reflected. A color control module acts on the radiation of the second wavelength and/or the third wavelength so that an intensity of the stimulated emission of the radiation of the second wavelength is adjusted to the radiation of the third wavelength.

A laser light source unit for vehicles is provided, having a resonator containing a first end mirror and a second end mirror and an active laser medium in between. The laser light source unit has a pump device for generating a pump radiation into the resonator. The pump radiation is configured such that laser light of the first wavelength, a second wavelength, and/or a third wavelength can be radiated. An intermediate mirror is configured so that the radiation of the second wavelength is reflected, and the radiation of the third wavelength is transmitted. A third end mirror is configured so that the radiation of the second wavelength is reflected. A color control module acts on the radiation of the second wavelength and/or the third wavelength so that an intensity of the stimulated emission of the radiation of the second wavelength is adjusted to the radiation of the third wavelength.

An optical device has a first photonic waveguide provided on a substrate, a second photonic waveguide provided on the substrate and extending side by side with the first photonic waveguide, and a looped waveguide continuously connecting the first photonic waveguide and the second photonic waveguide on the substrate, wherein a width of at least one of the first photonic waveguide or the second photonic waveguide varies continuously along an optical axis, between a first position located at a side opposite to the looped waveguide and a second position connected to the looped waveguide, and wherein cross sections of the first photonic waveguide and the second photonic waveguide are congruent at the second position, and are incongruent at the first position.

A technology is described for a Photonic Integrated Circuit (PIC) radio frequency (RF) oscillator. The PIC RF oscillator can comprise an optical gain media coupled to a first mirror and configured to be coupled to the PIC. The PIC can comprise a first optical cavity located within the PIC, a tunable mirror to form a first optical path between the first mirror in the gain media and the first tunable mirror, and a frequency tunable intra-cavity dual tone resonator positioned within the first optical cavity to constrain the first optical cavity having a common optical path to produce tow primary laser tones with a tunable frequency spacing. A photo detector is optically coupled to the PIC and configured to mix the two primary laser tones to form an RF output signal with a frequency selected by the tunable frequency spacing of the two primary tones.

A method includes driving, while producing a burst of pulses at a pulse repetition rate, a spectral feature adjuster among a set of discrete states at a frequency correlated with the pulse repetition rate; and in between the production of the bursts of pulses (while no pulses are being produced), driving the spectral feature adjuster according to a driving signal defined by a set of parameters. Each discrete state corresponds to a discrete value of a spectral feature. The method includes ensuring that the spectral feature adjuster is in one of the discrete states that corresponds to a discrete value of the spectral feature of the amplified light beam when a pulse in the next burst is produced by adjusting one or more of: an instruction to the lithography exposure apparatus, the driving signal to the spectral feature adjuster, and/or the instruction to the optical source.

A transmission type adaptive optical system that can be applied to a high power laser beam beyond a limit of deformable mirrors and corrects wavefront turbulence of a laser beam with adaptation to the wavefront turbulence is provided. By using a transmission type adaptive optical element of which a refractive index distribution changes based on temperature distribution thereof, a wavefront turbulence of a laser beam is corrected with adaptation to this wavefront turbulence. The wavefront turbulence is detected by a wavefront sensor and heating light in accordance with the detected wavefront turbulence is emitted to irradiate the transmission type adaptive optical element. The transmission type adaptive optical element transmits a laser beam as a target to correct a wavefront turbulence thereof and generates temperature distribution by the heating light and as a result generates the refractive index distribution.

A transmission type adaptive optical system that can be applied to a high power laser beam beyond a limit of deformable mirrors and corrects wavefront turbulence of a laser beam with adaptation to the wavefront turbulence is provided. By using a transmission type adaptive optical element of which a refractive index distribution changes based on temperature distribution thereof, a wavefront turbulence of a laser beam is corrected with adaptation to this wavefront turbulence. The wavefront turbulence is detected by a wavefront sensor and heating light in accordance with the detected wavefront turbulence is emitted to irradiate the transmission type adaptive optical element. The transmission type adaptive optical element transmits a laser beam as a target to correct a wavefront turbulence thereof and generates temperature distribution by the heating light and as a result generates the refractive index distribution.

An apparatus includes an optical splitter configured to receive an optical signal and to split the input optical signal to provide a first and a second optical signal. The apparatus further includes an interferometer comprising a first arm and a second arm, with the first arm being configured to receive the first optical signal, and the second arm being configured to receive the second optical signal. Notably a portion of the first arm is exposed to a reference gas that attenuates light of a characteristic wavelength. The apparatus further includes an optical coupler configured to receive an output optical signal from the first arm, and an output optical signal from the second arm and to provide a third optical signal; and a photodetector configured to receive the third optical signal, and to provide a photocurrent. The photocurrent increases when the difference between the characteristic wavelength and the wavelength of the optical signals increases. The apparatus also comprises a feedback control circuit configured to change the properties of the laser to be locked until an error signal indicative of the difference between the characteristic wavelength and the wavelength of the laser is substantially zero.

A line narrowing device includes first and second prisms disposed at positions different in a wavelength dispersion direction of any of the first and second prisms, a third prism disposed on the optical path of an optical beam and through which the beam width of the optical beam is enlarged and first and second parts of the optical beam are incident on the first and second prisms, respectively, a grating disposed across the optical path of the first part having passed through the first prism and the optical path of the second part having passed through the second prism, a first actuator configured to adjust the incident angle of the first part on the grating, a second actuator configured to adjust the incident angle of the second part on the grating, and a third actuator configured to adjust an energy ratio of the first and second parts.

A line narrowing device includes first and second prisms disposed at positions different in a wavelength dispersion direction of any of the first and second prisms, a third prism disposed on the optical path of an optical beam and through which the beam width of the optical beam is enlarged and first and second parts of the optical beam are incident on the first and second prisms, respectively, a grating disposed across the optical path of the first part having passed through the first prism and the optical path of the second part having passed through the second prism, a first actuator configured to adjust the incident angle of the first part on the grating, a second actuator configured to adjust the incident angle of the second part on the grating, and a third actuator configured to adjust an energy ratio of the first and second parts.