I do not know if this link has been posted here before.

It is a Martin Grabherr paper. He is a senior manager of Philips.

http://www.photonics.philips.com/pdf/New%20applications%20boost%20VCSEL%20quantities%20-%20recent%20developments%20at%20Philips.PDF

Here are some extracts :

Over the past years, two other major applications came into focus: optical interconnects in high performance computers or datacenters and smart sensors for mobile devices. In addition, VCSELs are penetrating into more and more power applications, primarily for illumination or IR heating.

The main markets for VCSELs in terms of channel count will be cabling in data centers, interconnects in High Performance Computers, and Routers. For example, a need of several hundred million VCSELs operated at 25 Gbps for High Performance Computers (HPC) is expected by IBM in 2020.

But higher bandwidths, more dense transceiver architecture, and the demand for low assembly costs will require to switch to flip-chip solutions.

Volume capability has to be built up to provide several 100 million channels per year, corresponding to thousands of 4 inch wafers. This requests for tenfold of today’s shipments which are assumed to be about 34 million channels into Datacom applications in 2013.

Having a closer look at sensors and other subsystems in today’s Smartphones opens a huge potential for VCSELs:

1. Laser Autofocus – already in the market

2. Proximity sensor – already in the market

3. Video signal to the display

4. Video signal from one or more cameras

5. Low noise microphone

6. Gesture recognition.

In an extremely optimistic scenario, one could imagine 5 to 10 VCSELs being used in a single Smartphone. For 2014 the number of Smartphones shipped in the world has been 1.3 billion units.

With increasing resolution of displays and cameras in smartphones, the respective stream of data is rapidly increasing. The corresponding need for higher data rates is challenging for electrical cables in terms of on board distances, EMI, power consumption, and mechanical flexibility. Optical links using VCSELs as emitters have been designed for this specific approach in order to address these constraint.

Further improvement in performance, cost, and production capabilities for VCSELs are required to stand up against the strong competition. One answer to this challenge is a well known learning from the semiconductor industry: scale up in size, standardization, and automation.