Abstract: It is an object of the invention to provide a holographic laser and an optical pickup, with which it is possible to read from and write to a plurality of types of optical disks with different read wavelengths, and to achieve a more compact apparatus. The holographic laser includes for example a package, two semiconductor laser elements and a photodiode for reading out signals accommodated within the package, a holographic element positioned proximate to or in close contact with the top of a glass window, and a wavelength separating element positioned proximate to or in close contact with the top of the holographic element. The holographic laser is integrally formed as a single component.

Abstract: An automated laser diode testing and burn-in system is disclosed. Initial device data is obtained by applying current to the device at room temperature and measuring the device parameters. The device is then subjected to a burn-in process at higher temperatures. Device performance is monitored throughout the burn-in process. Upon termination of the burn-in process the devices are cooled to room temperature and the post burn-in device power is measured again under the same test conditions. If the device parameters have changed by more than a particular amount the device is rejected. Otherwise, the device is accepted and installed in the next level assembly.

Abstract: It is an object of the invention to provide a holographic laser and an optical pickup, with which it is possible to read from and write to a plurality of types of optical disks with different read wavelengths, and to achieve a more compact apparatus. The holographic laser includes for example a package, two semiconductor laser elements and a photodiode for reading out signals accommodated within the package, a holographic element positioned proximate to or in close contact with the top of a glass window, and a wavelength separating element positioned proximate to or in close contact with the top of the holographic element. The holographic laser is integrally formed as a single component.

Abstract: One or more single mode waveguide devices are fiber coupled such that signals to an optical element affect the coupling of the waveguide device to an optical fiber. A number of systems and methods are disclosed to adjust the coupling of the waveguide device to the optical fiber. These include dithering the tunable optical element at different frequencies along differing axes and using a lock-in technique to derive an error signal for each degree of motion, using a beamsplitter to form a secondary image of the focused beam on a position-sensitive detector, the use of a chiseled fiber to generate reflections from the angled facets, using an additional laser for a secondary image, or obtaining a secondary image from an angledfiber or a parasitic reflection.

Abstract: An Er:YAG laser system has a resonant cavity including an Er:YAG rod pulse-pumped by a pulsed flashlamp. The pump-pulse repetition rate and average power is selected to provide a known essentially constant thermal-lensing power in the Er:YAG rod. Design parameters of the Er:YAG rod and the resonant cavity are selected to compensate for this thermal-lensing power. A shutter in the resonant cavity, when closed or open, respectively prevents or allows a laser output-pulse to be generated in response to a pump-pulse. Laser output-pulse duration is continuously variable and is controlled by controlling the duration of flashlamp-pulses. A sequence of laser output-pulses is controlled by opening and closing the shutter. This arrangement has the advantage that the laser output-pulse repetition rate can be selected to be the flashlamp-pulse repetition rate or some sub-multiple thereof while maintaining thermal-lensing power in the rod essentially constant and compensated for.

Abstract: An apparatus for unloading fluid, preferably pressurized gas, from containers in a controlled manner that protects the immediate area from exposure to the container contents. The device consists of an unloading housing, which is enclosed within at least one protective structure, for receiving the dispensed contents of the steel container, and a laser light source, located external to the protective structure, for opening the steel container instantaneously. The neck or stem of the fluid container is placed within the sealed interior environment of the unloading housing. The laser light passes through both the protective structure and the unloading housing to instantaneously pierce a small hole within the stem of the container. Both the protective structure and the unloading housing are specially designed to allow laser light passage without compromising the light's energy level. Also, the unloading housing allows controlled flow of the gas once it has been dispensed from the container.

Abstract: Electrical conductor comprising a glass fibre (12) with a hollow center within which is a liquid solution (14) containing D.sup.+ or other boson ions. Coherent light from a laser (15) is directed into the solution to render the boson ions coherent, inducing a superconducting state. In another embodiment, the laser is replaced by a microwave source.

Abstract: The invention relates to a method and an apparatus for reducing the diameter tolerance of a laser beam. A lens (3) is positioned so that one of the focal planes of the lens (3) is in the region of a limit (5) of the Rayleigh range of the beam (19). The lens (3) forms a second beam waist at a position (6), where a modulator (10) is placed. The beam (21) then passes through beam expansion apparatus (11,12,13) before being collimated by a lens (14). The collimated beam (25) is then focussed to a third beam waist at the recording drum (17), via a lens (18) and mirror (15).

Abstract: A push-pull pulsed gas laser which utilizes piston action to displace a laser gas from the laser cavity to a heat exchanger and return of the gas to the laser cavity between laser pulses to significantly reduce the volume of gas required for repetatively pulsed gas lasers and to reduce the average power required to recondition the laser gas.