Abstract: A planar wafer-level packaging method is provided for a laser and a monitor photo detector. The laser and photo detector are affixed to a planar substrate. The planar substrate provides electrical connections to the components. A lens cap with a microlens is formed and affixed to the substrate with a seal. The lens cap forms a hermetically sealed cavity enclosing the laser and photo detector. The inside surface of the lens cap has a reflective coating with a central opening over the emitting aperture of the laser. The central opening has an anti-reflective coating. Light from the laser is directed and shaped by the lens cap to couple into an external light guide. Residual light from the edge of the laser reflects off the inside surface of the lens cap and is incident upon the photo detector. In an alternate method, the laser may be packaged using flip-chip assembly.

Abstract: A uniform coating is provided using surface features. Multiple ridges or other shapes are fabricated near an area of interest to allow for uniform coating in between the ridges. Areas at either ends of the ridges are left open to allow for excess pooling of photoresist liquid and to aid in obtaining uniform coating. The photoresist liquid or other coating fluid is applied to the sample and spun dry. A soft-bake process is performed to evaporate remaining solvents. An element, such as a diffractive, refractive, or reflective grating structure, is then formed in the area of interest using the uniform photoresist coating.

Abstract: Laser diodes are formed with an outcoupling grating between two separate distributed Bragg reflectors. The devices have gain regions located between the reflector gratings for pumping the active region. The outcoupling grating couples light out of the waveguide normal to the surface if the grating spacings are equal to an integer number of wavelengths of the light within the cavity. If the gratings are not such an integer number, the light is coupled out of the cavity off the normal.

Abstract: A band-stop wavelength filter and TE-TM mode selector made using an absorptive layer on an optical waveguide is provided. At the correct thickness, refractive index, absorptive loss, and location of the absorptive layer, a relatively high fraction of guided-mode intensity flows in the absorptive layer for one polarization mode. A much smaller fraction flows for the perpendicular polarization mode and for wavelengths on both sides of the design center. The result is a broad-band-stop filter for the selected polarization mode. This device is capable of strong discrimination between TE and TM modes over a very broad bandwidth.

Abstract: A laser diode system is provided. The laser comprises first and second reflective gratings at each end of the laser. The laser further comprises an outcoupling grating between the first and second reflective gratings, wherein the outcoupling grating couples light out of the laser. The reflectors and outcoupling grating each have a unique wide-band reflective spectrum. A first laser cavity exists between the first and second reflective gratings. A second laser cavity exists between the first reflective grating and the outcoupling grating. A third laser cavity exists between the second reflective grating and the outcoupling grating, and a fourth laser cavity exists with in the outcoupling region. The overlap of reflective spectra determine the lasing wavelengths that reach resonance within each cavity. Wavelengths resonant in one cavity are suppressed in the others unless a wavelength is resonant in all cavities. This matching of mode intensities causes the outcoupled beam to be confined to a single wavelength.

Abstract: A surface emitting semiconductor laser system having four cavities that couple light from a single aperture. Each of the four cavities overlaps at the outcoupling aperture. Each cavity is fabricated to resonate at a different central wavelength, outputting a different frequency of light, each of which can be independently modulated.

Abstract: An apparatus and method of Wavelength Division Multiplexing (WDM) are provided. The WDM multiplexer includes a plurality of lasers, a plurality of collimating lenses and a single focusing lens. Each lens of the plurality of lenses is positioned so as to collimate a beam of light emitted by a laser of the plurality of lasers. The focusing lens is positioned to focus a plurality of collimated beams of light received from the plurality of lenses into substantially a point of light. The WDM multiplexer includes a receptacle that houses the plurality of lasers, the plurality of collimating lenses and the focusing lens.

Abstract: An electronic/photonic integrated circuit in which grating-outcoupled surface-emitting lasers are used both to provide external emission out of the plane of the chip (through gratings), and also to feed optical power into photonic waveguides parallel to the plane of the chip. Transistors are fabricated in a common multilayer semiconductor body with the lasers.

Abstract: A planar wafer-level packaging method is provided for a laser and a microlens. Light from the laser is directed and shaped by the microlens to couple into an external light guide. A plurality of such assemblies, each comprising a laser and a microlens may be assembled on a single planar substrate. A tapered surface is formed on the microlens. The microlens may be formed from a silicon substrate. The angle of the tapered surface causes an accurate cone or pyramid shape. The tapered surface is formed such that the axis of the cone or pyramid is aligned with the optical axis of the lens. The lens may then be aligned with the optical axis of the laser. A light guide receptacle is formed with a tapered surface that matches the tapered surface of the microlens. The tapered surface of the receptacle is formed such that the axis of the cone or pyramid is aligned with the optical axis of the receptacle. The receptacle may then be passively aligned with the microlens by mating the tapered surfaces.

Abstract: A laser source is provided by the present invention, comprising a laser diode and has an active region with asymmetric distributed Bragg reflectors (DBRs) at either end to reflect light within the cavity, and an outcoupling grating in the center of the device, which couples light out of the cavity. One DBR is long and shallow, with a narrow-band reflective spectrum. The other DBR is short and deep, with a wide-band reflective spectrum. The lasing wavelength is determined by the reflective spectrum overlap of the two DBRs. Since the shallow DBR is highly reflective to only one Fabry Perot wavelength, and the deep DBR is highly reflective to a wide band of Fabry-Perot wavelengths, it is the reflective spectrum of the shallow DBR that determines the lasing wavelength.

Abstract: A uniform coating is provided using surface features. Multiple ridges or other shapes are fabricated near an area of interest to allow for uniform coating in between the ridges. Areas at either ends of the ridges are left open to allow for excess pooling of photoresist liquid and to aid in obtaining uniform coating. The photoresist liquid or other coating fluid is applied to the sample and spun dry. A soft-bake process is performed to evaporate remaining solvents. An element, such as a diffractive, refractive, or reflective grating structure, is then formed in the area of interest using the uniform photoresist coating.

Abstract: A system capable of creating multiple beams of light using laterally coupled waveguides. Each beam is of a different central wavelength, capable of being generated on chip and coupled into a single fiber, and emitted from a single outcoupling grating (OCG). The present innovations can be used to create a multiple wavelength source generating multiple signals of different wavelengths simultaneously. The present innovations can also function as a tunable laser source system, capable of generating one of many different wavelength signals at a time. Waveguides are laterally coupled through, for example, evanescent coupling. The degree of coupling is controlled by varying the voltage applied to contacts attached to the waveguides at the coupling region.

Abstract: A laser diode system is provided. The laser comprises first and second reflective gratings at each end of the laser. The laser further comprises an outcoupling grating between the first and second reflective gratings, wherein the outcoupling grating couples light out of the laser. The reflectors and outcoupling grating each have a unique wide-band reflective spectrum. A first laser cavity exists between the first and second reflective gratings. A second laser cavity exists between the first reflective grating and the outcoupling grating. A third laser cavity exists between the second reflective grating and the outcoupling grating, and a fourth laser cavity exists with in the outcoupling region. The overlap of reflective spectra determine the lasing wavelengths that reach resonance within each cavity. Wavelengths resonant in one cavity are suppressed in the others unless a wavelength is resonant in all cavities. This matching of mode intensities causes the outcoupled beam to be confined to a single wavelength.

Abstract: An exemplary optical isolator, which may use a magnetic-composite material made of a ferromagnetic-composite, and method for making the same are provided. The optical isolator may include a core, a cladding, and a magnetic-composite material. The core is operable to allow a light wave incident a first end to propagate to a second end to define a positive propagation direction, and to allow a light wave incident the second end to propagate to the first end to define a negative propagation direction. The cladding is positioned relative the core and includes a thinned segment of the cladding with a cladding thickness operable to allow an optical field penetration through the thinned segment of the cladding by a light wave that propagates either in the positive or negative propagation direction. The thinned segment has a length that extends relative to a portion of the core.

Abstract: A laser system comprises a laser diode with an active region and reflectors at both ends. An outcoupling aperture is located between the reflectors to couple light out of the device through the surface. The gain region increases in width as it nears the outcoupling aperture.

Abstract: A band-stop wavelength filter and TE-TM mode selector made using an absorptive layer on an optical waveguide is provided. At the correct thickness, refractive index, absorptive loss, and location of the absorptive layer, a relatively high fraction of guided-mode intensity flows in the absorptive layer for one polarization mode. A much smaller fraction flows for the perpendicular polarization mode and for wavelengths on both sides of the design center. The result is a broad-band-stop filter for the selected polarization mode. This device is capable of strong discrimination between TE and TM modes over a very broad bandwidth.

Abstract: A planar wafer-level packaging method is provided for a laser and a monitor photo detector. The laser and photo detector are affixed to a planar substrate. A lens cap with a microlens is formed and affixed to the substrate with a seal. The lens cap forms a hermetically sealed cavity enclosing the laser and photo detector. Light from the laser is directed and shaped by the lens cap to couple into an external light guide. In an alternate method, the laser may be packaged using flip-chip assembly. A precision protrusion is also provided in the receptacle that fits into a photo-lithographically defined cavity in the substrate of the planar subpackage, thereby passively effecting and maintaining alignment of the axis of the microlens with respect to the central axis of the mating ferrule. The axial distance, in the direction of the laser beam, between the lens and the mating connector ferrule is controlled by the connector stop or front face of the MT ferrule.

Abstract: A planar wafer-level packaging method is provided for a laser and a monitor photo detector. The laser and photo detector are affixed to a planar substrate. The planar substrate provides electrical connections to the components. A lens cap with a microlens is formed and affixed to the substrate with a seal. The lens cap forms a hermetically sealed cavity enclosing the laser and photo detector. The inside surface of the lens cap has a reflective coating with a central opening over the emitting aperture of the laser. The central opening has an anti-reflective coating. Light from the laser is directed and shaped by the lens cap to couple into an external light guide. Residual light from the edge of the laser reflects off the inside surface of the lens cap and is incident upon the photo detector. In an alternate method, the laser may be packaged using flip-chip assembly.

Abstract: A laser source is provided by the present invention, comprising a laser diode and has an active region with asymmetric distributed Bragg reflectors (DBRs) at either end to reflect light within the cavity, and an outcoupling grating in the center of the device, which couples light out of the cavity. One DBR is long and shallow, with a narrow-band reflective spectrum. The other DBR is short and deep, with a wide-band reflective spectrum. The lasing wavelength is determined by the reflective spectrum overlap of the two DBRs. Since the shallow DBR is highly reflective to only one Fabry Perot wavelength, and the deep DBR is highly reflective to a wide band of Fabry-Perot wavelengths, it is the reflective spectrum of the shallow DBR that determines the lasing wavelength.

Abstract: A modulation technique for optical signals. A laser diode having an outcoupling grating in the waveguide between two reflectors is provided. A second waveguide is positioned next to the first waveguide. The first end of the second waveguide is optically connected to the first waveguide on one side of the outcoupling grating, while the second end of the second waveguide is optically connected to the first waveguide on the other side of the outcoupling grating. Switches are provided that control the amount of light coupled between the waveguides. For example, when the switches are in a first state, no light is coupled between the two waveguides, and all the light stays in the laser diode or is coupled out of the outcoupling grating, while none of the light couples into the second grating; and when the switches are in a second state, some or all of the light from the first waveguide is coupled into the second waveguide. By toggling the states of the switches, the light emitted from the laser diode is modulated.