摘要:
An integrated optical transmitter for use in an optical system has an optical head assembly with an optical beam generator for providing an optical beam and a lens assembly collecting the optical beam and generating therefrom a formed optical beam. Interface optics receive the formed optical beam and provide optical coupling so as to minimize insertion loss to the optical beam. Also included is an optical modulator for receiving the optical beam from the interface optics and for providing a modulated optical beam in response to received modulation signals. The optical modulator is coupled to the interface optics to be in a fixed relationship therewith.
摘要:
Disclosed in an optical fiber feedthrough that meets the industry load standard of 1 kg. The optical fiber feedthrough includes a length of optical fiber including a buffer layer and a core. The length of fiber extends along a longitudinal axis and typically through a passage in a package wall for communicating an optical signal between the exterior and the interior of the package. The optical fiber feedthrough includes a volume of bonding agent adhering to the buffer layer and to a bonding surface integral with the package, the volume of bonding agent disposed for asymmetrically securing the fiber to the package such that a load of less than approximately 1 kg applied to a first end of the length of fiber substantially not transmitted to the other end of the length of fiber. The invention also includes feedthrough assembly having a feedthrough to which the length of optical fiber is asymmetrically secured. The feedthrough body can be secured to the package wall of the optical package.
摘要:
An apparatus for monitoring and controlling the wavelength of laser radiation includes at least one optical filter for receiving laser radiation and for transmitting and reflecting first and second filtered beams, respectively. Alternatively, the first and second beams may be transmitted by separate filters (32, 34). The beams are filtered according to respective first and second spectral filter functions that cross at least one crossing wavelength. A beam comparison element (20) compares the first and second filtered beams (36,38) and produces an error signal (22) representative of the deviation of the wavelength of the laser radiation from a set-point wavelength. The beam comparison element (20) can include first and second optical detectors (40, 42) and error signal (22) by taking a ratio or the difference of the signals detected by the detectors. Varying the angle of incidence of the laser radiation upon at least one optical filter varies the spectral filter function of that filter for selecting or varying the operating wavelength of the laser (12). A laser wavelength controller (24) can receive the error signal (22) for stabilizing or tuning the wavelength of the laser radiation. Several embodiments of the invention are disclosed.
摘要:
An optical amplifier for amplifying a plurality of signal components of a mult-wavelength optical beam passing through an optical fiber includes a portion of the optical fiber doped with a rare earth ion to amplify the optical signal wherein the gain spectrum as a function of the wavelength is nonuniform. The optical amplifier further includes a gain flattening module to compensate for the nonuniform gain spectrum of the doped fiber by attenuating each of the channels of the amplified signal to equalize the gain. A gain equalization module compensates for varying gain fluctuations due to the adding and subtracting of signal components. The gain equalization module adjusts dynamically each signal component of the optical beam such that the amplitudes of the signal components are substantially equal, in response to a plurality of control signals. Each control signal is representative of the degree of attenuation required to equalize the signal components. The respective control signals are generated by a loop status monitor that includes a waveguide for demultiplexing the optical beam, and a detector array that determines the amplitude of each signal component. A controller generates the control signals in dependence of the amplitude of the signal components.
摘要:
A method of fabricating an optical device incorporates two different techniques for formation of different structures of the device on the same substrate. Individual processes such as Titanium indiffusion and annealed proton exchange in LiNb03 require significantly different temperature ranges for comparable waveguide formation. The present method combines these processes and allows for temperature tuning of the optical parameters of passive and active components, for instance coupling lengths of directional couplers, associated with one section of the device without altering the optical parameters of similar components in the other sections. The process improves yield for devices which employ more than one precisely fabricated optical directional coupler by creating an extra degree of process freedom. The method includes the steps of diffusing a first material at a first temperature into a first portion of the substrate to define a first guide for the optical beam. The first material diffuses significantly into the substrate only at temperature comparable to, or greater than the first temperature. The method also includes the step of diffusing a second material into a second portion of the substrate at a second temperature to define a second guide for the optical beam. The second temperature is substantially less than the first temperature such that approximately none of the first material in the substrate continues to diffuse while the second material diffuses into the substrate.
摘要:
An optic intensity modulator includes a substrate (10) of an optic material that is conductive to light and acoustic waves and has both the electro-optic and piezoelectric properties. The optical modulator generally consists of a Mach-Zender interferometer comprising a pair of associated elongated light waveguides (11, 12) formed in the substrate, with the waveguides extending substantially coextensively with one another, and being separated from one another by a transverse distance that gradually varies along the courses of the waveguides. Different phase shifts are induced by imposing variable electric fields onto each of the waveguides by means of electrodes (21, 22, 23). Because of the varying spacing between the waveguides along their courses, the tendency of the acoustic waves that are generated during the operation of the modulator due to the piezoelectric effect to resonate between the waveguides at certain frequencies, is eliminated thus reducing the corresponding noise distortion.
摘要:
An optical fiber (14) having a core, a cladding layer (52), and a midsection (12) forming a hermetic seal to the fiber (14). First and second sections of a length of the optical fiber are separated by the midsection (12) that includes a jacket (18) hermetically sealed to the fiber (14), the jacket (18), having a hermetically sealable outer surface. First and second stress relief joints (16) are formed between the jacket (18) and the buffer layers (15) of the first and second sections of the length of the fiber (14). A method is disclosed for fabricating the optical fiber (14) having a hermetically sealable section (12).
摘要:
A differential input optical modulator, suited for an electrical driver with complementary outputs is provided by the present invention. One embodiment uses an X-cut LiNb03 substrate, with or without a buffer layer, to reduce cost of manufacture in comparison to some known devices that employs a Z-cut LiNbO∩ substrate. These prior art devices require both buffer and charge bleed-off layers. The present invention also includes a quasi-symmetric electrode structure in which the applied fields run parallel to the surface of the substrate.