Abstract: Embodiments are directed to a beam combining apparatus including a light source having a first emitter with a first output wavelength and at least one second emitter having a second output wavelength. A beam conditioning section is configured to collimate the output of the emitters and provide diffractive optical feedback to the emitters and a diffractive beam combining device is configured to spatially overlap the output wavelengths of the first emitter and at least one second emitter.

Abstract: The present invention provides controlling the locked wavelength of individual diodes in an array such that the spectral output of the array when taken as a whole is of the desired form for a given application. In one embodiment, a volume holographic grating is formed that has a wavelength that varies on the filter in accordance with the physical position of a laser emitter in a diode bar or stack. The system can be used in connection with a collimator disposed to receive the output of a diode bar or stack of diode bars. The modified filter is then disposed adjacent the output of the collimator to provide a suitable shaped spectral output. This technique can be applied to stacks of laser diode bars, where each bar can be made to operate at any desired wavelength, or even individual emitters within the bar, such that the combined spectral output is designed for a particular application.

Abstract: A laser utilizes feedback from a volume holographic grating integrated in a collimating lens as a wavelength standard to lock the laser output wavelength to its desired value. This feedback is optical, wherein a volume hologram reflection grating is used to generate optical feedback into the laser gain region. Fabrication of the integrated volume hologram grating lens elements is by either first recording the grating in a rectangular parallelepiped of material and then shaping the lens from it, or alternatively by first shaping the material into the desired shape and then recording the grating with the use of an apparatus composed of an optical block within which a cavity is present to accept the lens and index matching fluid.

Abstract: The invention is a method of packaging volume holographic filters to modify the temperature sensitivity using fixed volume holographic grating filters (VHG). These filters are recorded using either a phase mask or a two-beam method. A mechanical constraint is provided to the filter by way of a stress. This stress can be applied equally to both simple reflection grating as well as slanted reflection grating. One way is to use a filter-anisotropic tube arrangement where the tube is made by either stacking washers of precise inner diameter or by wrapping a wire around a central filter core. To modify the thermal wavelength coefficient of the filter, clamps comprising plates and screws are used, the filter is inserted into a substrate, or the filter is sandwiched between substrates.

Abstract: A tunable optical filter includes a movable reflector, such as a three-dimensional microelectromechanical system (MEMS) actuated mirror and a plurality of holographic gratings each having a predetermined Bragg wavelength to select the wavelength to be filtered or dropped from broadband or wavelength-multiplexed input optical signals.