Finisar

About: Finisar is a company organization based out in Sunnyvale, California, United States. It is known for research contribution in the topics: Signal & Laser. The organization has 900 authors who have published 1523 publications receiving 22634 citations.

Optical subassembly having insertable cylindrical sleeve

Abstract: An optical subassembly (“OSA”) for use in optical communications modules is disclosed. The OSA solves various issues related to the insertion and removal of an optical fiber connector into and from the OSA receptacle, including hard plug, wiggle performance, and shavings production. In one embodiment, an optical communications module is disclosed and includes a housing and an optical subassembly of the present invention partially contained within the housing. The optical subassembly includes various components, including a body composed of a first material, and a plug receptacle formed with the body. The plug receptacle includes an inner surface on which surface features, such as threads, are formed. A hollow cylindrical sleeve composed of a second material is received in the plug receptacle such that the outer sleeve surface engages the surface features of the plug receptacle inner surface and such that an optical fiber connector can be received by the sleeve.

System and method for protecting eye safety during operation of a fiber optic transceiver

Abstract: A single-chip integrated circuit, sometimes called a controller, controls operation of a transceiver having a laser transmitter and a photodiode receiver. The controller includes memory for storing information related to the transceiver, and analog to digital conversion circuitry for receiving a plurality of analog signals from the laser transmitter and photodiode receiver, converting the received analog signals into digital values, and storing the digital values in predefined locations within the memory. Comparison logic compares one or more of these digital values with predetermined setpoints, generates flag values based on the comparisons, and stores the flag values in predefined locations within the memory. Control circuitry in the controller shuts off the laser transmitter in response to comparisons of signals with predetermined setpoints that indicate potential eye safety hazards.

Electronic-Photonic Integrated Circuit for 3D Microimaging

Abstract: An integrated electronic-photonic phase-locked loop (PLL) modulates the frequency of a tunable laser for use in frequency-modulated continuous-wave (FMCW) lidar 3D imaging. The proposed lidar can perform 180k range measurements per second. The rms depth precision is 8 $\mu \text{m}$ at distances of ±5 cm from the range baseline. The range window is 1.4 m, with a precision of 4.2 mm at the edges of the window. Optical circuitry, including input light couplers, waveguides, and photodiodes, is realized on a 3 mm $\times $ 3 mm silicon-photonic chip. The 0.18- $\mu \text{m}$ CMOS ASIC of the same area comprises the front-end transimpedance amplifier, analog electro-optical PLL, and digital control circuitry consuming 1.7 mA from a 1.8 V supply and 14.1 mA from a 5-V supply. The latter includes 12.5-mA bias current for the distributed Bragg reflector section of the tunable laser. The two chips are integrated using through-silicon-vias implemented in the silicon-photonic chip.

Vertical cavity surface emitting laser using photonic crystals

Abstract: A vertical cavity surface emitting laser (VCSEL) using photonic crystals. Photonic crystals are formed such that the active region of the VCSEL is bounded by the photonic crystals. The photonic crystals have a periodic cavity structure that reflects light of certain wavelengths through the active region of the VCSEL such that laser light at the wavelengths is generated. Additional photonic crystals can be formed to increase the bandwidth of the VCSEL. The photonic crystals can also be combined with distributed bragg reflector layers to form the mirrors of a VCSEL.

Method and apparatus for transmitting a signal using thermal chirp management of a directly modulated transmitter

Abstract: A fiber optic transmitter comprising a digital driver adapted to adjust the crossing point of a digital base signal, an optical source adapted to receive the digital base signal and produce a frequency modulated optical signal, and an optical spectrum reshaper adapted to convert the frequency modulated optical signal to an amplitude modulated optical signal. A method for transmitting a signal, comprising: adjusting the crossing point of a digital base signal; providing the adjusted signal to an optical source to produce a frequency modulated optical signal; and providing the frequency modulated optical signal to an optical spectrum reshaper to convert the frequency modulated optical signal to an amplitude modulated optical signal.