A passively, Q-switched laser is described. The laser may operate at an eye-safe lasing wavelength of 1.34 microns and use a gain element of Nd:YVO.sub.4 and a saturable absorber element of V:YAG with a space separating the gain element and saturable absorber element. The Q-switched laser is pumped by a grating stabilized laser diode. The laser may be used in laser ranging applications.

An actively cooled end-pumped solid-state laser gain device includes a bulk solid-state gain medium. An input-end of the gain medium receives a pump laser beam incident thereon and propagating in the direction toward an opposite output-end. The metal foil is disposed over a face of the gain medium extending between the input- and output-ends. A housing cooperates with the metal foil to form a coolant channel on the face the gain medium. The coolant channel has an inlet and an outlet configured to conduct a flow of coolant along the metal foil from the input-end towards the output-end. The metal foil is secured between the gain medium and portions of the housing running adjacent to the coolant channel. The metal foil provides a reliable thermal contact and imparts little or no stress on the bulk gain medium.

A wearable heads-up display includes a power source, laser sources, and a lightguide. A photodetector is positioned to detect an intensity of a test light emitted at a perimeter of the lightguide from an optical path within the lightguide. A laser safety circuit provides a control to reduce or shut off a supply of electrical power from the power source to the laser sources in response to an output signal from the photodetector indicating that the detected intensity is below a threshold.

A laser is disclosed having a housing formed of a block of glass-ceramic. The block is machined (or otherwise formed) to define one or more channels that act as a waveguide in two dimensions for light within the laser resonator. The channels extend between cavities also formed within the block which retain optical components of the laser, e.g. one or more of the gain medium, cavity mirrors, intermediate reflectors etc. The positioning, shape and size of each cavity is bespoke for the optical component it holds in order that each optical component is retained in optical alignment rigidly against the sides of the cavity.

A laser system includes a laser diode that, upon activation, selectively produces a continuous wave of laser light or uniformly spaced, intermittent pulses of laser light. The system further includes a laser focuser with a plurality of lenses that focus the laser light produces by the laser diode and direct the laser light to an optical resonator. The optical resonator includes a lasing medium that, when intersected by the laser light from the laser diode, produces a beam of laser light with a wavelength that may be used for therapeutic treatment. The system is operable to produce the therapeutic laser light when the laser diode is operating in either the continuous wave mode or the pulsed mode, without moving components of the system relative to one another.

A solid state laser module for amplification of laser radiation including a laser gain medium disk. The disk has a pair of generally parallel surfaces that receive, reflect, or transmit laser radiation. At least one perimetral optical medium is disposed adjacent a peripheral edge of the laser gain medium disk and in optical communication therewith. A source of optical pump radiation directs optical pump radiation through the perimetral optical medium and into the laser gain medium disk to pump the laser gain medium to produce optical gain at the laser wavelength. A dichroic beam splitter is located between the optical pump source and the perimetral optical medium to prevent amplified spontaneous emission generated within the laser gain medium from illuminating the source of optical pump radiation.

Laser amplifier apparatus 100 includes gain medium 10 for receiving seed pulse(s) 2 and pump pulse(s) 3 and for emitting laser pulse(s) 1, resonator device 20 including gain medium and resonator mirrors spanning resonator beam path 25 with multi-pass geometry, coupler arrangement 30 for coupling seed pulse(s) and pump pulse(s) to resonator device and coupling output laser pulse(s) out of resonator device, and gain medium cooling device 40A. Resonator mirrors include first and second telescope mirrors 21, 22 with mutual distance and common focal section therebetween and defining optical axis z of resonator device, and first and second groups of end mirrors 23, 24 between mirrors 21 and 22 for forming path 25, wherein end mirrors are on ring-shaped section surrounding optical axis z, and resonator are arranged such that emitting sections of the gain medium are imaged in themselves. A method of amplifying laser pulses is also described.

A passively, Q-switched laser operating at an eye safe wavelength of between 1.2 and 1.4 microns is described. The laser may operate at a lasing wavelength of 1.34 microns and use a gain element of Nd:YVO.sub.4 and a saturable absorber element of V:YAG. The systems and methods to produce short pulses having a pulse duration less than 1 ns and high energy pulses having pulse energies greater than 2 μJ are described.

[Object] To provide a compact and high-performance laser device and a laser apparatus.

[Solving Means] A laser device according to the present disclosure includes an excitation light source having a first reflective layer with respect to a first wavelength; a laser medium having a second reflective layer with respect to a second wavelength on a first surface facing to the excitation light source and a third reflective layer with respect to the first wavelength on a second surface opposite to the first surface; and a saturable absorber having a fourth reflective layer with respect to the second wavelength on a third surface opposite to the laser medium.

A passively, Q-switched laser operating at an eye safe wavelength of between 1.2 and 1.4 microns is described. The laser may operate at a lasing wavelength of 1.34 microns and use a gain element of Nd:YVO.sub.4 and a saturable absorber element of V:YAG. The position of the resonator axial mode spectrum relative to a gain peak of the gain element is controlled to yield desired characteristics in the laser output.