摘要:
An optical switch constructed from first and second waveguides. The first and second waveguides have ends disposed across a gap such that light traversing the first waveguide enters the second waveguide when the gap is filled with a liquid having a first index of refraction, whereas light traversing the first waveguide is reflected by the gap when the gap is filled with a material having a second index of refraction that is substantially different from the first index of refraction. The gap is part of a trench that contains a liquid droplet made from a droplet material having the first index of refraction. The droplet is located in the trench and is movable between the first and second positions in the trench, the droplet filling the gap in the first position. The gap is filled with a material having the second index of refraction when the droplet is in the second position. The droplet may be moved using an electric field generated by a plurality of electrodes arranged such that an electrical potential applied between a first pair of the electrodes creates an electric field in a region of the trench containing the first position. The droplet can also be moved by differentially heating two edges of the droplet so as to create a net force on the droplet in a direction parallel to the direction of the trench. The heating can be accomplished by illuminating one edge of the droplet with light of a wavelength that is absorbed by the droplet material.
摘要:
A controllable optical attenuator comprising an optical waveguide which extends longitudinally along the optical attenuator. The optical waveguide has an exposed surface and a core that is positioned directly adjacent the exposed surface. The attenuator further comprises at least one elongated chamber which is formed transversely to the longitudinal extent of the optical waveguide and a liquid droplet which is disposed within the elongated chamber, the droplet being movable along the chamber from a position lateral of the optical waveguide exposed surface to a position in which contact is made between the liquid droplet and the optical waveguide exposed surface. When the liquid droplet is positioned so as to contact the exposed surface of the optical waveguide, a portion of the optical signal transmitted along the waveguide core is absorbed by the droplet so as to attenuate the transmitted signal.
摘要:
A polarization control device, comprising: a liquid crystal device containing a liquid crystal material with an optical anisostropy with substantially homeotropically aligned molecules when in a neutral electrical field state; a plurality of electrodes for applying an electrical field to change an orientation of the molecules of the liquid crystal material from their alignment in the neutral electrical filed state; a circuit for applying a voltage to the electrodes; and an optical system for directing light through the liquid crystal material.
摘要:
An auto-focus system employing a tunable liquid crystal lens is provided that collects images at different optical power values as the liquid crystal molecules are excited between a ground state and a maximum optical power state tracking image focus scores. An image is acquired at a desired optical power value less than maximum optical power established with the liquid crystal molecules closer a fully excited state than the maximum optical power state having the same image focus score. This drive signal employed during image acquisition uses more power than was used to achieve the same optical power value during the auto-focus scan, while actively driving the liquid crystal molecules is fast. A pause due to image transfer/processing delays after acquisition is employed to allow slow relaxation of the liquid crystal molecules back to the ground state in preparation for a subsequent focus search.
摘要:
An optical apparatus and method for selectively transmitting optical signals utilizes an optical component having a controllable optical state to selectively manipulate the optical signals so that transmission of the optical signals through the optical apparatus is controlled. The optical apparatus is configured so that optical signals from a first port of the optical apparatus are transmitted to a second port of the optical apparatus regardless of the optical state of the optical component. The optical apparatus is further configured so that optical signals from the second port are not transmitted to the first port unless the optical component is switched to an active optical state.
摘要:
An auto-focus system employing a tunable liquid crystal lens is provided that collects images at different optical power values as the liquid crystal molecules are excited between a ground state and a maximum optical power state tracking image focus scores. An image is acquired at a desired optical power value less than maximum optical power established with the liquid crystal molecules closer a fully excited state than the maximum optical power state having the same image focus score. This drive signal employed during image acquisition uses more power than was used to achieve the same optical power value during the auto-focus scan, while actively driving the liquid crystal molecules is fast. A pause due to image transfer/processing delays after acquisition is employed to allow slow relaxation of the liquid crystal molecules back to the ground state in preparation for a subsequent focus search.
摘要:
An auto-focus system employing a tunable liquid crystal lens is provided that collects images at different optical power values as the liquid crystal molecules are excited between a ground state and a maximum optical power state tracking image focus scores. An image is acquired at a desired optical power value less than maximum optical power established with the liquid crystal molecules closer a fully excited state than the maximum optical power state having the same image focus score. This drive signal employed during image acquisition uses more power than was used to achieve the same optical power value during the auto-focus scan, while actively driving the liquid crystal molecules is fast. A pause due to image transfer/processing delays after acquisition is employed to allow slow relaxation of the liquid crystal molecules back to the ground state in preparation for a subsequent focus search.
摘要:
A polymerizable liquid crystalline monomer is described comprising a polymerizable first terminal group, a central portion, and a second terminal group, wherein the monomer is capable of filament formation. Filaments can form as a result of an isotropic to smectic phase transition and can subsequently be polymerized by photoinitiation, for example.