Finisar Corporation

Other

Finsiar Corporation

Anthony Ho

James Edward Stewart

Lucy G Hosking

Andreas G Weber

Darin James Douma

Jan Lipson

Rudolf J Hofmeister

John Hsieh

Chun Lei

Yew-Tai Chieng

Jeffrey Bryant Price

Jeff Price

Rudy Hofmeister

Lucy Grace Hosking

A microprocessor is used to control the temperature of a laser emitter and thereby regulate the wavelength of optical signals from the laser. A serial interface in the microprocessor provides input and output lines to a host device, and temperature lookup tables are stored in nonvolatile memory. Control logic processes information stored in the memory as well as information on operating conditions of the laser emitter to precisely control the temperature of the laser emitter. A thermo-electric cooler adjusts the temperature of the laser emitter.

Control circuit for optoelectronic module with integrated temperature control

A loss of signal assert and de-assert level programming mechanism in an optical transceiver coupled to a host computing system. A control module is connected to the host so as to receive the programmable loss of signal level. A post-amplifier detects when the receive power drops below a loss of signal level. However, in this case, instead of the loss of signal level being static, a loss of signal level adjustment mechanism changes the loss of signal level detected by the post-amplifier as directed by the programmable loss of signal level received from the host. The loss of signal assert and de-assert levels may be calibrated by comparing receive power to the threshold for assertion and de-assertion of the loss of signal.

Programmable loss of signal detect hardware and method

This disclosure concerns systems, methods and devices for temperature-based control of laser performance. One example of a method is performed in connection with a laser of an optoelectronic transceiver. In particular, the laser is operated over a range of temperatures and the optical output of the laser is monitored. During operation of the laser, the bias current and current swing supplied to the laser are adjusted to the extent necessary to maintain a substantially constant optical output from the laser over the range of temperatures.

Systems, devices and methods for temperature-based control of laser performance

Optoelectronic devices and methods are used to maintain a CWDM transmitter operating within design parameters over an extended ambient temperature range. In order to avoid excessive wavelength drift with temperature shifts, lasers in the CWDM transmitters are heated or cooled to a selected temperature, for example by using a thermoelectric cooler. By heating and cooling the lasers, any wavelength drift that an ambient temperature variation might inflict on the laser is minimized to the range hotter or colder than the selected temperature. As the temperature range of the laser increases above the selected temperature, the AC swing driving the laser is increased to maintain a sufficient extinction ratio for acceptable transmitter performance.

Temperature control for coarse wavelength division multiplexing systems

Methods and processes are disclosed for calibrating optoelectronic devices, such as optoelectronic transceivers and optoelectronic receivers, based upon an avalanche photodiode breakdown voltage. In general, the method involves adjusting a reverse-bias voltage of the avalanche photodiode until avalanche breakdown of the avalanche photodiode occurs. An optimized APD reverse-bias voltage is then determined by reducing the reverse-bias voltage at which avalanche breakdown occurs by a predetermined offset voltage. This process is performed at a variety of different temperatures. Information concerning each temperature and the corresponding optimized APD reverse-bias voltage is stored in a memory of the optoelectronic device.

Method for calibrating an optoelectronic device based on APD breakdown voltage

An optoelectronic transceiver includes first and second controller ICs. Each controller IC includes logic, a memory, an interface, and at least one input port. Each memory is configured to store digital diagnostic data and has a unique serial device address to allow a host access to each of these controller ICs separately and independently. At least some of the digital diagnostic data is common to both the first controller IC and the second controller IC. The inclusion of two controller ICs allows the same diagnostic data to be stored in completely different memory mapped locations. This allows hosts that are preconfigured differently to read different memory mapped locations on the different controller ICs to obtain the same diagnostic data.

Optoelectronic transceiver having dual access to onboard diagnostics

A controller for controlling the reverse-bias voltage of an avalanche photodiode in a transceiver or receiver. The controller includes memory for storing information related to the avalanche photodiode, and analog to digital conversion circuitry for receiving an analog signal corresponding to the temperature of the avalanche photodiode, converting the received analog signal into a digital value, and storing the digital value in a predefined location within the memory. Control circuitry in the controller controls the operation of the avalanche photodiode and a temperature lookup table store in the memory. A serial interface enables a host device to read from and write to locations within the memory. The invention also controls the reverse-bias voltage of an avalanche photodiode in a transceiver or receiver.

Avalanche photodiode controller circuit for fiber optics transceiver

The optoelectronic transceiver includes first and second controller ICs. Each controller IC includes logic, a memory, an interface, and at least one input port. Each memory is configured to store digital diagnostic data and has a unique serial device address to allow a host access to each of these controller ICs separately and independently. At least some of the digital diagnostic data is common to both the first controller IC and the second controller IC. The inclusion of two controller ICs allows the same diagnostic data to be stored in completely different memory mapped locations. This allows hosts that are preconfigured differently to read different memory mapped locations on the different controller ICs to obtain the same diagnostic data.

A method for compensating for wavelength drift in a fiber-optic laser transmitter includes 1) controlling a temperature within the optoelectronic assembly at a defined level; 2) driving the optoelectronic assembly to emit light, wherein the emitted light has a wavelength that is within a channel of operation, the channel of operation including a range of wavelengths centered around a channel center wavelength; 3) accessing from memory within the optoelectronic assembly a control value associated with the temperature of the optoelectronic assembly at defined points within an operational lifetime of the optoelectronic assembly; and 4) recalculating the defined level by reference to the control value, whereby a wavelength of the optoelectronic assembly is maintained within the channel of operation despite an expected drift of wavelength.

Age compensation in optoelectronic modules with integrated temperature control

A method for calibrating a multi-channel laser emitter in an optoelectronic transceiver or an optoelectronic transmitter for a first wavelength includes monitoring the wavelength of optical signals from the laser emitter while varying its temperature as well as other operating conditions, and then storing calibration information in the memory of a microprocessor. The initial values of the calibrating procedure are reset and the calibrating procedure is repeated to obtain calibration information for a next desired wavelength.

Calibration of a multi-channel optoelectronic module with integrated temperature control

A method of maintaining desirable optical performance of optical emitters over temperature variations is disclosed. The optical performance of an optical emitter in terms of power, extinction ratio, jitter, mask margin and general fiber optic transmitter eye quality can be maintained by the present invention over a wide range of temperatures. Advantageously, the present invention enables the use of inexpensive optical emitters in optoelectronic transceivers and optoelectronic transmitters.

Maintaining desirable performance of optical emitters over temperature variations

The method and apparatus for compensating a photo-detector allows both regulation and monitoring of the photo-detector to be performed with a common digital controller. The controller accepts input of monitored operational parameters including received signal strength and temperature. The controller provides as an output a bias control signal which regulates a positive the positive or negative side bias voltage power supply for the photo-detector. The controller maintains the bias voltage to the photo-detector at levels which optimize the gain and signal-to-noise ratios for the photo-detector thereby facilitating the decoding of the received signal over a broad range of signal strengths and temperatures. The controller includes a corresponding digital signal strength and temperature compensators the outputs of which summed with a summer to provide the bias control signal. The digital signal strength compensator also provides as an output a monitor signal a level of which corresponds to the actual signal strength received by the photo-detector after compensation for the variable gain of the photo-detector resulting from the bias voltage level. A transceiver as well as methods and means for monitoring a photo-detector are also disclosed.

Growing community of inventors

Sunnyvale, CA, United States of America

Anthony Ho