Transmitter diode for industrial fibre optic systems

The emitter is available as a housed fibre-optic transmitter module in a range of housing and connector styles. Popular housed variants include the H13AE2850IR - a PCB-mount version with ST connector - and the H22E2850IR, which is the SMA PCB-mounting variant; both feature a precision-machined, all metal body and a rugged screw-mount design for reliable mechanical connection to circuit boards.

The device delivers a typical coupled power of 813µW at 100mA into 200µm glass optical fibre, and can also be aligned to deliver good levels of power into fibre sizes as small as 50µm. Operating at the infrared 850nm wavelength, the device features a very fast rise and fall time of just 12ns.

The firm also says that following significant investment in enhanced capacity, it has been able to reduce manufacturing lead times considerably on this part versus industry norms for this type of device. Whereas typical manufacturing lead times for industrial f/o transmitters can often exceed 16 weeks, OMC say they can turn around transmitter batches based on the FDE2850 in closer to 6-8 weeks, and that this can be further expedited in many cases.

As with all of OMC’s fibre-optic transmitter and receiver devices, the customer can take advantage of OMC’s Active Component Alignment technology. With many such transmitters on the marketplace, the device only specifies a minimum performance into one particular fibre size/type and/or at one nominal drive current.

This means that unless the customer is using those precise conditions – which is rarely the case – they have to rely on typical figures in their link design, which can lead to inconsistency and yield issues as the minimum and maximum performance of the device under their application conditions is undefined.

When OMC’s Active Component Alignment is employed, the emitter is powered up and monitored while it is being aligned and installed into the housing during manufacture of the housed transmitter, and can therefore be characterised at each customer’s drive current and fibre size, allowing a strictly defined launch power window to be specified.

This means that the customer can design their system in the knowledge that each and every device will perform within this known window when driven at their chosen drive current and coupled with the size and type of fibre they are using.

OMC’s Commercial Director, William Heath said: “By designing and manufacturing from die-level upwards, we have engineered a cost-effective transmitter that offers fast speeds and good launch powers, and can be produced to lead times that are very short compared to those traditionally applying to this type of device. 

“To complement the part, the engineering support we offer customers and our device customisation capabilities allow us to engineer effective alternatives to obsolete and hard-to-find fibre-optic components, while at the same time enhancing reliability and reducing overall cost of the fibre-optic system.”