Lightwave Logic Inc (LWLG)

[Photonics_Guy]

Proto - Again great questions.

PG, looking at Slide 14 from this Poet presentation, they are modeling an Optical Engine for a Transceiver priced at $150 to $250 for 100Gbs (using 25Gbs modulators)

POET AGM Presentation

I guess I am still confused at the really high price of Drivers, and how Poet is able to model a complete Transceiver so low priced?

And for the less technically minded here, this Poet presentation Slide 19 gives a good layout of the Transceiver components, and color codes the Electronics vs the Optics

POET Sept 2018 Presentation

I have not followed POET closely as I am more enamored with the approach that LWLG is taking. But here are a few comments on the slides you mentioned above.

1. The block diagram of their transceiver is lacking a lot of detail. For example:
- They show no interconnects from the driver to the modulator, I expect there is some control input to properly bias the DC operating point of their modulator
- There is no RF input shown to the modulator, although there must certainly be one.

2. This revision of their transceiver shows four 25Gbps XCVRs in parallel to realize a 100Gbps solution.
- It is easier (cheaper) to build a linear, low-noise RF amplifier that has an input RF Bandwidth of 20GHz than it is to build one for 77GHz.

3. I have to assume that their modulator can only provide amplitude modulation as they are limited to <10km solutions.
- This is supported by the fact they only show a PIN diode for the detector in the Rx direction. Phase modulation requires a more elaborate discriminator receiver as opposed to a simple avalanche diode.
- Long-haul and Metro solutions are predominantly using phase coherent (phase modulation) protocols.

To be sure, POET has a great solution at a very competitive price. It may be a compelling solution for short-haul data centers. IMO, they are going to be limited in how far they can go with a 25Gbps modulator. How many can you XCVRs can they pack together in parallel? I don't know. They are touting they can go to 400Gbps. But it does seem somewhat self-limiting to me.

They do not discuss the Vpi voltage rating of their modulators, at least that I noticed on a quick read through their slides. Again, once you go to wafer scale integration, the costs for the power amp transistors and other electronics in the drivers drop significantly, and economies of scale can be exploited. With that said, there is still a cost that is required for the Driver. And that is a cost that is NOT required for LWLG modulators, since the Vpi of their modulators allows them to be driven directly from the incoming RF modulating signal without amplification.

The fact that LWLG Modulators support both amplitude and phase coherent modulation opens them up to all markets...short-haul, metro and long-haul applications. The challenge for LWLG is to settle the question of stability once and for all and to get their polymer technology integrated into true PIC solutions, rather than discrete modulators.

PG