A collinear T-cavity VECSEL system generating intracavity Hermite-Gaussian modes at multiple wavelengths, configured to vary each of these wavelengths individually and independently. A mode converter element and/or an astigmatic mode converter is/are aligned intracavity to reversibly convert the Gaussian modes to HG modes to Laguerre-Gaussian modes, the latter forming the system output having any of the wavelengths provided by the spectrum resulting from nonlinear frequency-mixing intracavity (including generation of UV, visible, mid-IR light). The laser system delivers Watt-level output power in tunable high-order transverse mode distribution.

A laser system, comprised of: a laser cavity; a gain medium a pump, a saturable absorber (SA); a first mirror and a second mirror; wherein a ratio of an area of the beam area within the SA to an area of the laser beam within the gain medium is greater than 1, and wherein the beam generates a gain medium radius spot on the gain medium and a saturable absorber radius spot on the saturable absorber such that a ratio between a saturable absorber radius spot on the saturable absorber and the gain medium radius spot on the gain medium is within a range of 1.7-7 is disclosed. A method for using the laser system e.g., for producing a pulsed energy is further disclosed.

To appropriately change an output of laser light without deteriorating laser characteristics. A control section of a laser machining device controls, when a target output is larger than a predetermined threshold, an output of laser light by changing a driving current supplied to an excitation light source and, on the other hand, controls, when the target output is equal to or smaller than the threshold, the output of the laser light by changing a duty ratio of a Q switch while keeping the driving current supplied to the excitation light source substantially fixed.

To prevent an output decrease of laser light due to impurities that could be formed in a guide-light emitting device or an imaging device. A laser-light guiding section includes a transmission window section, an optical component disposed to cause an optical path of the UV laser light emitted from the laser-light output section and an optical path of transmitted light transmitted through the transmission window section to cross, and a sealing member in which the transmission window section is provided, the sealing member configuring a sealed space for airtightly housing the optical component. At least one of a guide-light emitting device configured to emit guide light for visualizing a scanning position of the UV laser light toward the transmission window section and an imaging device configured to receive light for imaging a workpiece via the transmission window section is disposed on the outer side of the sealed space.

The present invention relates to a diode laser with external spectrally selective feedback. It is an object of the invention is to provide an external cavity diode laser with wavelength stabilization which allows an increased overall output power in the desired wavelength range. According to the invention, an external cavity diode laser arrangement is disclosed comprising: an active medium positioned inside an internal laser cavity (10), the internal laser cavity (10) comprising an exit facet (12) adapted for outcoupling laser radiation; an external frequency-selective element (14) positioned outside the internal laser cavity (10) and adapted for wavelength stabilization of the laser radiation; a beam divider (16) positioned outside the internal laser cavity (10) and adapted to divide the outcoupled laser radiation (BO) into a first beam (B1) extending along a first beam path (P1) and a second beam (B2) extending along a second beam path (P2), the first beam (B1) having higher radiant intensity than the second beam (B2) and the first beam path (P1) being different from the second beam path (P2); and an intensity control means to control the radiant intensity incident to the external frequency selective element (14); wherein the external frequency-selective element (14) and the intensity control means are arranged in the second beam path (P2). The intensity control means in the second beam path (P2) may comprise a polarization modifying means (18) and a polarizer (20) in order to reduce thermal stress at the frequency-selective element (14).

A spectral beam combining system includes a plurality of input fibers and a prism having a curved input surface. The plurality of input fibers are attached to the curved input surface. The spectral beam combining system also includes an immersion grating defined on a second surface of the prism, a protective cap disposed over the immersion grating, and an output surface.

The present application is directed to various architectures of a laser oscillator which include an optical element, reflective, refractive, or diffractive injection device for injection seeding and/or locking a laser oscillator.

A laser resonator comprising a specially designed front mirror 32. The front mirror 32 together with a rear mirror form a resonator cavity. As well as having a resonator cavity reflective surface 42, the front mirror 32 also has an output coupling reflective surface 44 which forms a continuation of the resonator cavity reflective surface 42 and extends at an angle thereto so as to direct a beam laterally out of the cavity. The output coupling reflective surface 44 and the resonator cavity reflective surface 44 are joined by a soft rounded edge 40 of arcuate cross-section, this rounded transition suppressing diffraction ripples that would otherwise be generated if the edge were hard, i.e. sharp.

The present invention relates to a novel stand-off distance chemical detector system such as can be used, for example, for standoff detection of explosives. Instead of a conventional lasing medium, a Pr:YAG or Pr:BYF based UV laser is used which can be advantageously implemented in Raman spectroscopy.

A collinear T-cavity VECSEL system generating intracavity Hermite-Gaussian modes at multiple wavelengths, configured to vary each of these wavelengths individually and independently. A mode converter element and/or an astigmatic mode converter is/are aligned intracavity to reversibly convert the Gaussian modes to HG modes to Laguerre-Gaussian modes, the latter forming the system output having any of the wavelengths provided by the spectrum resulting from nonlinear frequency-mixing intracavity (including generation of UV, visible, mid-IR light). The laser system delivers Watt-level output power in tunable high-order transverse mode distribution.