摘要:
Simplified laser drivers for closed path digital optical cables and digital optical cables including the simplified laser drivers. The laser driver can include less transistors than conventional laser drivers for optical communication cables. The laser can include a bias source and modulation source. The bias source can have a single constant current bias point for all laser diodes. The modulation current source can have a single temperature coefficient for all laser diodes. The laser driver can exclude, for example, any one of or combination of temperature compensation of the modulation or bias current sources, external programming of the modulation or bias current sources, power control based on output of the laser diode, and/or control based on feedback received from a monitor device or other sensor within the cables.
摘要:
An optical transceiver for detecting an incoming light beam and for transmitting an outgoing light beam along a common optical axis is provided. Such an optical transceiver provides a compact optical transceiver that is suitable for a wide variety of applications.
摘要:
Simplified laser drivers for closed path digital optical cables and digital optical cables including the simplified laser drivers. The laser driver can include less transistors than conventional laser drivers for optical communication cables. The laser can include a bias source and modulation source. The bias source can have a single constant current bias point for all laser diodes. The modulation current source can have a single temperature coefficient for all laser diodes. The laser driver can exclude, for example, any one of or combination of temperature compensation of the modulation or bias current sources, external programming of the modulation or bias current sources, power control based on output of the laser diode, and/or control based on feedback received from a monitor device or other sensor within the cables.
摘要:
An optical structure that reduces the effects of spontaneous emissions from the active region of a laser. An optical structure includes optimizations to reduce the effects of spontaneous emissions. The optical structure includes a VCSEL with top and bottom DBR mirrors and an active region connected to the mirrors. The optical structure further includes a photodiode connected to the VCSEL. One or more optimizations may be included in the optical structure including optically absorbing materials, varying the geometry of the structure to change reflective angles, using optical apertures, changing the reflectivity of one or more mirrors, changing the photodiode to be more impervious to spontaneous emissions, and using ion implants to reduce photoluminescence efficiency.
摘要:
An optical structure that reduces the effects of spontaneous emissions from the active region of a laser. An optical structure includes optimizations to reduce the effects of spontaneous emissions. The optical structure includes a VCSEL with top and bottom DBR mirrors and an active region connected to the mirrors. The optical structure further includes a photodiode connected to the VCSEL. One or more optimizations may be included in the optical structure including optically absorbing materials, varying the geometry of the structure to change reflective angles, using optical apertures, changing the reflectivity of one or more mirrors, changing the photodiode to be more impervious to spontaneous emissions, and using ion implants to reduce photoluminescence efficiency.
摘要:
A system and method for VCSEL (vertical cavity surface emitting laser) polarization control is disclosed, including methods and apparatus comprising a component package (302, 304) having self-aligning features (316, 318), for indicating an alignment axis (320, 322), and an upper surface aperture (314) formed therein, a vertical cavity surface emitting laser device (308) having two emission polarizations (204) normal to one another, disposed within the component package and aligned such that each emission polarization is at about 45 degrees with respect to the alignment axis, and a linear polarization element (400, 402, 406) having a polarization direction (206), spanning the aperture and disposed such that the polarization direction is parallel to the alignment axis.
摘要:
Methods and apparatus for monitoring the power level of a multi-wavelength optical signal are provided. Also provided are methods and apparatus for adjusting the power level of selected optical emitters to compensate for the changes in power levels.
摘要:
Embodiments of the present invention provide a system for increasing an operational life of a VCSEL. The system can include control circuitry for reducing an amount of bias current at high temperatures and increasing a power of the laser at low temperatures. This control circuitry can further include at least one of a temperature sensor, a Field Programmable Gate Array, a read only memory module, and an electrically erasable programmable read only memory module (EEPROM). In alternate embodiments, the control circuitry can further include a lookup table that sets the bias current depending on a temperature of the laser. The laser can be part of an optoelectronic transceiver module which can include, by way of example and not limitation, SFP, XFP, X2, XAUI, XENPAK, XPAK, GBIC, 8G, 16G, and other optoelectronic modules.
摘要:
A photodiode and a method of fabricating a photodiode for reducing modal dispersion and increasing travel distance. The central region of the photodiode is made less responsive to incident light than a peripheral region of the photodiode. The less responsive central region discriminates the lower order modes such that only the higher order modes are incident on the more responsive peripheral region. Because the lower order modes are subtracted, the range of propagation constants is reduced and modal dispersion is also reduced.
摘要:
Methods and apparatus for alignment of TO cans with photodiodes on fiber-optic receptacles. The methods and apparatus make use of direct connections to photodiodes or connections to Received Signal Strength Indicator (RSSI) outputs to align TO cans in fiber-optic receptacles. An optical source, such as a laser diode, can be powered by a low-frequency or DC source. This optical source can direct light into the fiber-optic receptacle. The TO can is manipulated in a barrel of the fiber-optic receptacle. The current through the photodiode or the RSSI output is monitored to determine when light directed into the photodiode is at a maximum or above a predetermined threshold. The TO can is fixed in the barrel when the light directed into the photodiode is at the maximum or predetermined threshold.