Abstract: Three-dimensional structures of arbitrary shape are fabricated on the surface of a substrate through a series of processing steps wherein a monolithic structure is fabricated in successive layers. A first layer of photoresist material is spun onto a substrate surface and is exposed in a desired pattern corresponding to the shape of a final structure, at a corresponding cross-sectional level in the structure. The layer is not developed after exposure; instead, a second layer of photoresist material is deposited and is also exposed in a desired pattern. Subsequent layers are spun onto the top surface of prior layers and exposed, and upon completion of the succession of layers each defining corresponding levels of the desired structure, the layers are all developed at the same time leaving the three-dimensional structure.

Abstract: A ring-type laser including a traveling wave cavity which incorporates at least first and second straight cavity sections and at least one curved cavity section. Corresponding first ends of the straight cavity sections are interconnected at a first light-emitting facet, and second ends of the straight sections are interconnected by the curved waveguide. Additional curved and straight sections can be linked to provide various ring configurations.

Abstract: Three-dimensional structures of arbitrary shape are fabricated on the surface of a substrate through a series of processing steps wherein a monolithic structure is fabricated in successive layers. A first layer of photoresist material is spun onto a substrate surface and is exposed in a desired pattern corresponding to the shape of a final structure, at a corresponding cross-sectional level in the structure. The layer is not developed after exposure; instead, a second layer of photoresist material is deposited and is also exposed in a desired pattern. Subsequent layers are spun onto the top surface of prior layers and exposed, and upon completion of the succession of layers each defining corresponding levels of the desired structure, the layers are all developed at the same time leaving the three-dimensional structure.

Abstract: A ring-type laser including a traveling wave cavity which incorporates at least first and second straight cavity sections and at least one curved cavity section. Corresponding first ends of the straight cavity sections are interconnected at a first light-emitting facet, and second ends of the straight sections are interconnected by the curved waveguide. Additional curved and straight sections can be linked to provide various ring configurations.

Abstract: A controllable, unidirectional ring laser having a reduced length includes at least one curved waveguide section, at least one partially transmitting facet, and a mechanism for producing unidirectional propagation of light within the waveguide cavity. The mechanism includes, in one embodiment, an external reflector which may be either planar or curved, in the path of emitted light from a waveguide facet. In another embodiment of the invention, the reflector is replaced by a source of light directed at the emitting facet of the waveguide, while another embodiment includes the use of an asymmetric element in the cavity. If desired, two unidirectional devices can be used selectively to produce a reversible waveguide.

Abstract: Three-dimensional structures of arbitrary shape are fabricated on the surface of a substrate through a series of processing steps wherein a monolithic structure is fabricated in successive layers. A first layer of photoresist material is spun onto a substrate surface and is exposed in a desired pattern corresponding to the shape of a final structure, at a corresponding cross-sectional level in the structure. The layer is not developed after exposure; instead, a second layer of photoresist material is deposited and is also exposed in a desired pattern. Subsequent layers are spun onto the top surface of prior layers and exposed, and upon completion of the succession of layers each defining corresponding levels of the desired structure, the layers are all developed at the same time leaving the three-dimensional structure.

Abstract: A semiconductor ring-type optical device having an optical cavity with at least one partially transmitting facet which serves as an emergence region for light propagating within the optical cavity has the upper surface of the cavity coated with a conductive layer which is divided into at least two segments so as to provide two separate electrodes to allow application of separate voltages to the two segments. When different voltages are applied, one segment of the laser will carry a lower current density than the other, resulting in a lower gain under the electrode having the lower voltage and causing the generated laser wavelength to experience a shift to shorter wavelengths. Accordingly, variations in the voltage applied to the two electrodes allows tuning of the laser output wavelength.

Abstract: A ring-type laser including a traveling wave cavity which incorporates at least first and second straight cavity sections and at least one curved cavity section. Corresponding first ends of the straight cavity sections are interconnected at a first light-emitting facet, and second ends of the straight sections are interconnected by the curved waveguide. Additional curved and straight sections can be linked to provide various ring configurations.

Abstract: A process and apparatus for generating a mail message for multiple recipients which identify to a respective recipient an attention level. A list of addresses for the recipient is created along with a mail message to be sent to all of the recipients. Appended to each address is a tag representing an attention level for the recipients. A text message is created for each of the recipients which includes the addresses and related tag. The text message and related tags are forwarded to the recipients. Each recipient displays on an electronic mail terminal a text message addressed to him. The attention level indication contained in the tag of the message is used to alert the recipient with an attention level assigned to the message for the recipient. The attention level may also be indicated by highlighting specific portions of the text in associating a tag with the recipient's address identifying for that recipient a portion of the text message to be highlighted.