Abstract: An optical fiber device may include a core including a primary section and a secondary section. The secondary section may include at least one insert element inserted within the primary section at an off-center location with respect to a center of the primary section. The secondary section may twist about an axis of the optical fiber device along a length of the optical fiber device. A rate of twist at which the secondary section twists about the axis may increase from a first end of the optical fiber device toward a second end of the optical fiber device. The secondary section being twisted about the axis may cause an optical beam, launched at the first end of the optical fiber device, to be at least partially converted to a rotary optical beam at the second end of the optical fiber device.

Abstract: A device may splice, at a target splice point, a first end of a twisted fiber having a non-concentric core to an input end of a target fiber having a concentric core to form a spliced fiber wherein the concentric core of the target fiber and the non-concentric core of the twisted fiber have a particular offset at the target splice point. The device may taper at least a portion of the twisted fiber to form a tapered region of the spliced fiber and such that the particular offset at the target splice point corresponds to a pre-configured core offset wherein the target splice point is within the tapered region of the spliced fiber.

Abstract: An optical fiber device may include a unitary core including a primary section and a secondary section, wherein at least a portion of the secondary section is offset from a center of the unitary core, wherein the unitary core twists about an optical axis of the optical fiber device along a length of the optical fiber device, and wherein a refractive index of the primary section is greater than a refractive index of the secondary section; and a cladding surrounding the unitary core.

Abstract: An optical fiber device may include a unitary core including a primary section and a secondary section, wherein at least a portion of the secondary section is offset from a center of the unitary core, wherein the unitary core twists about an axis of the optical fiber device along a length of the optical fiber device, and wherein a refractive index of the primary section is greater than a refractive index of the secondary section; and a cladding surrounding the unitary core.

Abstract: An optical fiber device may include a unitary core including a primary section and a secondary section, wherein at least a portion of the secondary section is offset from a center of the unitary core, wherein the unitary core twists about an optical axis of the optical fiber device along a length of the optical fiber device, and wherein a refractive index of the primary section is greater than a refractive index of the secondary section; and a cladding surrounding the unitary core.

Abstract: A device may determine at least one metric related to a plurality of laser pulses associated with a Q-switched laser. The device may determine a statistical metric for the at least one metric related to the plurality of laser pulses. The device may determine that the statistical metric satisfies a threshold level of deviation of the at least one metric related to the plurality of laser pulses from a baseline value for the at least one metric. The device may indicate laser degradation of the Q-switched laser based on determining that the statistical metric satisfies the threshold.

Abstract: A second harmonic generator may include a combiner to combine a fundamental optical beam with a residual fundamental optical beam. The second harmonic generator may include a second harmonic crystal, coupled to the combiner, to generate a second harmonic optical beam from the fundamental optical beam and the residual fundamental optical beam. Upon generation of the second harmonic optical beam, the residual fundamental optical beam may exit the second harmonic crystal.

Abstract: An optical fiber device may include a unitary core including a primary section and a secondary section, wherein at least a portion of the secondary section is offset from a center of the unitary core, wherein the unitary core twists about an optical axis of the optical fiber device along a length of the optical fiber device, and wherein a refractive index of the primary section is greater than a refractive index of the secondary section; and a cladding surrounding the unitary core.

Abstract: A second harmonic generator may include a combiner to combine a fundamental optical beam with a residual fundamental optical beam. The second harmonic generator may include a second harmonic crystal, coupled to the combiner, to generate a second harmonic optical beam from the fundamental optical beam and the residual fundamental optical beam. Upon generation of the second harmonic optical beam, the residual fundamental optical beam may exit the second harmonic crystal.

Abstract: A cascaded harmonic generator, for cascaded optical harmonic generation from an optical beam provided by a laser source, may include a second harmonic generator to generate a second harmonic optical beam based on a residual beam associated with the optical beam. The cascaded harmonic generator may include a third harmonic generator to generate a third harmonic optical beam based on the second harmonic optical beam and the optical beam. The third harmonic generator may be positioned in an optical path upstream from the second harmonic generator. A harmonic generator delay time, associated with the optical path, may be approximately equal to, or may be an approximate integer multiple of, a laser source round-trip time.

Abstract: A cascaded harmonic generator, for cascaded optical harmonic generation from an optical beam provided by a laser source, may include a second harmonic generator to generate a second harmonic optical beam based on a residual beam associated with the optical beam. The cascaded harmonic generator may include a third harmonic generator to generate a third harmonic optical beam based on the second harmonic optical beam and the optical beam. The third harmonic generator may be positioned in an optical path upstream from the second harmonic generator. A harmonic generator delay time, associated with the optical path, may be approximately equal to, or may be an approximate integer multiple of, a laser source round-trip time.

Abstract: A cascaded harmonic generator, for cascaded optical harmonic generation from an optical beam provided by a laser source, may include a second harmonic generator to generate a second harmonic optical beam based on a residual beam associated with the optical beam. The cascaded harmonic generator may include a third harmonic generator to generate a third harmonic optical beam based on the second harmonic optical beam and the optical beam. The third harmonic generator may be positioned in an optical path upstream from the second harmonic generator. A harmonic generator delay time, associated with the optical path, may be approximately equal to, or may be an approximate integer multiple of, a laser source round-trip time.

Abstract: Cascaded optical harmonic generators and methods for cascaded optical harmonic generation are disclosed. Relative disposition of individual harmonic generators of a cascaded harmonic generator in an optical path of the fundamental optical beam may be reversed. In a third harmonic generator, the fundamental optical beam may enter the third harmonic crystal first, and the second harmonic crystal second. When the fundamental optical beam enters the third harmonic crystal first, the fundamental light may remain non-depleted by second harmonic generation process.

Abstract: Cascaded optical harmonic generators and methods for cascaded optical harmonic generation are disclosed. Relative disposition of individual harmonic generators of a cascaded harmonic generator in an optical path of the fundamental optical beam may be reversed. In a third harmonic generator, the fundamental optical beam may enter the third harmonic crystal first, and the second harmonic crystal second. When the fundamental optical beam enters the third harmonic crystal first, the fundamental light may remain non-depleted by second harmonic generation process.

Abstract: The invention discloses an actively Q-switched laser with an intracavity nonlinear coupler in which a stable optical frequency converted output is generated. A Gain Fluctuation Insensitivity Condition is defined and described for several examples. The nonlinear coupler with a coupling level which satisfies this Condition permits stable laser operation with minimal interaction between pulses, even when the pulses are clipped by the Q-switch. Thus, the output pulse duration and repetition frequency of the disclosed laser can be varied over a large range substantially independent of laser gain level and dynamics. Second and third harmonic optical frequency conversion is demonstrated, although the disclosed laser is applicable to other optical frequency conversion regimes as well.

Abstract: A laser apparatus is disclosed. The apparatus includes a Neodymium-doped lasing material having first and second surfaces and a passive Q-switch optically coupled to the second surface. The first-surface is substantially transparent to a pump radiation and substantially reflective to laser radiation generated by an interaction between the pump radiation and the Neodymium-doped lasing material. The laser radiation is characterized by a vacuum wavelength corresponding to an atomic transition from the 4F3/2 level to the 4I9/2 level of Neodymium in the lasing material. The second surface transmits at least a portion of the laser radiation. The lasing material and Q-switch are configured to produce pulses of the laser radiation characterized by a pulse length of greater than zero and less than about 1.5 nanoseconds and a pulse repetition rate greater than about 100 kHz. A PQSL laser, an apparatus for generating blue light and a display system based on the laser apparatus are also disclosed.

Abstract: A light source is disclosed having a pulsed laser, a fiber amplifier optically coupled to the pulsed laser, and a nonlinear frequency converting element optically coupled to the fiber amplifier. The pulsed laser, e.g., a passively Q-switched laser, is configured to generate light pulses characterized by a pulse length of less than about 1.7 nsec and sufficiently large that a frequency bandwidth of the pulses after they emerge from the fiber amplifier is less than an acceptance bandwidth of the nonlinear frequency converting element. The laser is pulsed at a pulse repetition rate sufficiently large that the fiber amplifier does not spontaneously emit radiation between pulses. In such a source, the fiber amplifier is substantially free of stimulated Brillouin scattering and self-phase modulation may be held to a level that does not reduce conversion of infrared radiation to visible radiation. Such a light source can be combined with an image generator and a scanner in an image projection system.

Abstract: A light source is disclosed having a pulsed laser, a fiber amplifier optically coupled to the pulsed laser, and a nonlinear frequency converting element optically coupled to the fiber amplifier. The pulsed laser, e.g., a passively Q-switched laser, is configured to generate light pulses characterized by a pulse length of less than about 1.7 nsec and sufficiently large that a frequency bandwidth of the pulses after they emerge from the fiber amplifier is less than an acceptance bandwidth of the nonlinear frequency converting element. The laser is pulsed at a pulse repetition rate sufficiently large that the fiber amplifier does not spontaneously emit radiation between pulses. In such a source, the fiber amplifier is substantially free of stimulated Brillouin scattering and self-phase modulation may be held to a level that does not reduce conversion of infrared radiation to visible radiation. Such a light source can be combined with an image generator and a scanner in an image projection system.