摘要:
A surface-emitting laser (10), in which light is emitted vertically at one end from a 45.degree angled facet (22), includes a second end (28) having a perpendicular facet from which light is emitted horizontally, for monitoring.
摘要:
A method and structure for producing lasers (10) having good optical wavefront characteristics, such as are needed for optical storage includes providing a laser (14) wherein an output beam emerging from the laser front facet (16) is essentially unobstructed by the edges of the semiconductor chip (12) m order to prevent detrimental beam distortions The semiconductor laser structure (14) is epitaxially grown on a substrate (12) with at least a lower cladding layer (20), an active layer (22), an upper cladding layer (24), and a contact layer (26) Dry etching through a lithographically defined mask produces a laser mesa (14) of length lc and width bm Another sequence of lithography and etching is used to form a ndge structure (32) with width w on top of the mesa (14) The etching step also forming mirrors, or facets (16, 18), on the ends of the laser waveguide structures (32) The length I5 and width bs of the chip (12) can be selected as convenient values equal to or longer than the waveguide length lc and mesa width bm respectively The waveguide length and width are selected so that for a given defect density D, the yield YD is larger than 50 %
摘要:
An etched-facet single lateral mode semiconductor photonic device is fabricated by depositing an anti reflective coating on the etched facet, and depositing a reflectivity modifying coating in a spatially controlled manner to modify the spatial performance of the emitted beam.
摘要:
A ring cavity laser (20) has at least two facets (32,34) and a mechanism is provided to produce unidirectional propagation and light emission at a first wavelength. A source of laser light (60) at a second wavelength is injected into the cavity to reverse the direction of propagation and to produce emission at the second wavelength.
摘要:
A surface-emitting laser (10), in which light is emitted vertically at one end from a 45.degree angled facet (22), includes a second end (28) having a perpendicular facet from which light is emitted horizontally, for monitoring.
摘要:
A ring-type laser (40) including a traveling wave cavity which incorporates at least first and second straight cavity sections (42, 44) and at least one curved cavity sections (48). Corresponding first ends of the straight cavity sections are interconnected at a first light-emitting facet (62), and second ends of the straight sections are interconnected by the curved section (48). Additional curved and straight sections can be linked to provide various ring configurations.
摘要:
Pince-nez moulded in one piece, comprising a substantially planar structure which has a first rim provided with a first lens and a second rim provided with a second lens, said structure having a plane which passes through said first and second rims and said first and second lenses, said first and second rims each being extended by a linkage which connects them together, said linkage being designed to be in contact with a holding element intended to be placed on the nose of a user, characterized in that said linkage is curved and has a first and a second point of inflection.
摘要:
A laser chip having a substrate, an epitaxial structure on the substrate, the epitaxial structure including an active region and the active region generating light, a waveguide formed in the epitaxial structure extending in a first direction, the waveguide having a front etched facet and a back etched facet that define an edge-emitting laser, and a first recessed region formed in said epitaxial structure, the first recessed region being arranged at a distance from the waveguide and having an opening adjacent to the back etched facet, the first recessed region facilitating testing of an adjacent laser chip prior to singulation of the laser chip.