A method and apparatus for characterizing an optical element. The optical element is part of a laser and is mounted on a translation stage to scan the optical element transverse to an intracavity laser beam. A performance characteristic of the laser is recorded as a function of position of the optical element.

The passively q-switched diode end-pumped solid-state laser is used the gain medium made of Er:Yb doped crystal and the Q-switch made of Co.sup.2+:MgAl.sub.2O.sub.4 crystal. The optical elements are optimally designed for the resonator to achieve pulse energy in a range 0.5 mJ<E<2mJ with the pulse width in a range of 4 ns-15 ns. The resonator is appropriate to use in laser rangefinders, target designator, and other products in military and civilian applications.

A system includes a heat sink module and a driving circuit module. The heat sink module includes stepped through-holes that each includes a cylindrical upper and lower portions connected by a ring-shaped surface. The bottom surface of the heat sink module includes grooves that respectively pass through the lower portions of respective sequences of the stepped through-holes. The driving circuit module includes conductive connectors and electrical driving surfaces that are disposed external to the heat sink module. Each conductive connector lies within a respective groove in the bottom surface of the heat sink module. The conductive connectors include internal connectors that each link at least two stepped through-holes in a respective sequence of stepped through-holes passed by a respective groove, and include external connectors that each link at least one stepped through-hole in the respective sequence of stepped through-holes to the electrical driving surfaces.

An amplifier assembly may include a first heat sink plate that includes a first channel, a second heat sink plate that includes a second channel, and an amplifier rod disposed in the first channel and the second channel. The second heat sink plate may be connected with the first heat sink plate such that the first channel and the second channel align. The amplifier rod may be connected to the first heat sink plate and the second heat sink plate by a non-eutectic solder.

A laser level system including a laser level, the laser level projecting at least one laser line. The system also includes a bracket on which the laser level is mounted and a battery pack. The bracket includes a battery pack receptacle into which the battery pack is removably coupled. The battery pack powers the laser level. The battery pack has a maximum initial battery pack voltage (measured without a workload) of at least 18 volts. The system also includes at least one electrical conductor which delivers power from the battery pack in the battery pack receptacle to the laser level.

A fluid-cooled laser amplifier module (100) is disclosed which comprises: a casing; a plurality of slabs (110) of optical gain medium oriented in parallel in the casing for cooling by a fluid stream (154, 156); a polarisation rotator (120) disposed between a first group of one or more slabs (111) of the optical gain medium and a second group of one or more slabs (112) of the optical gain medium; optical windows (150, 152) for receiving an input beam or pulse (130) for amplifying by the slabs and for outputting the amplified beam or pulse (140); and fluid stream ports (155, 157) for receiving and discharging the fluid stream for cooling the slabs.

An optical device may include an enclosure including an optical aperture and a plurality of optical components positioned within the enclosure, where the plurality of optical components are to emit and/or receive light through the optical aperture. The optical device may include at least one heating element or cooling element to provide an isothermal environment to the plurality of optical components, where the at least one heating element or cooling element is thermally coupled with the enclosure.

Apparatus and methods for producing ultrashort optical pulses are described. A high-power, solid-state, passively mode-locked laser can be manufactured in a compact module that can be incorporated into a portable instrument. The mode-locked laser can produce sub-50-ps optical pulses at a repetition rates between 200 MHz and 50 MHz, rates suitable for massively parallel data-acquisition. The optical pulses can be used to generate a reference clock signal for synchronizing data-acquisition and signal-processing electronics of the portable instrument.

A solid state laser apparatus includes a plurality of cold heads, a cooling apparatus, laser media and a seed light source. The cooling apparatus is configured to cool the plurality of cold heads. The laser media are arranged in contact with each of the plurality of cold heads, and configured to amplify a first laser beam and reflect the first laser beam. The seed light source is configured to irradiate a first laser medium of the laser media with the first laser beam. The first laser medium is arranged on a first of the cold heads. The laser media are configured to reflect the first laser beam irradiated to the first laser medium to a second laser medium of the laser media. The second laser medium is arranged on a second of the cold heads. The cold heads are configured to cool the laser media.

A semiconductor device includes a detector structure. The detector structure includes an integrated circuit on a substrate, and a photo detector on an upper surface of the integrated circuit that is opposite the substrate, where the substrate is non-native to the photo detector. A System-on-Chip apparatus includes at least one laser emitter on a non-native substrate, at least one photo detector on the non-native substrate, and an input/output circuit. The at least one photo detector of the second plurality of photo detectors is disposed on an integrated circuit between the at least one photo detector and the non-native substrate to form a detector structure.