I was recently reading an article about the upcoming USB3 Vision interface standard – essentially a discussion around the impact of USB3 Vision on GigE Vision, (its sister standard from the AIA). Though I agree that USB3 Vision is the new predator, I disagree that GigE Vision is its primary target. Here’s why.
Let’s compare USB3 Vision to some of the fundamental characteristics of the most popular digital camera interfaces in our industry: Camera Link BASE, Firewire IIDC and GigE Vision.
The above table clearly shows that USB3 Vision is a clear winner in terms of raw bandwidth. It challenges any of the other interfaces listed, and provides a nice migration path for new CMOS Image Sensors. USB3 Vision is by nature a robust protocol, building on the bulk endpoint made available by the USB3 standard.
According to the most recent AIA camera study, Camera Link BASE represents the vast majority of shipped Camera Link units. But can it rise to the challenge posed by USB3 Vision? The table shows that this will be a difficult endeavor. Camera Link BASE is the most expensive interface to deploy due to frame grabber and cable costs. Its bandwidth is limited (3 taps at 85 MHz) and more importantly, the Camera Link standard does not have any provision for robustness.
An interesting fact is that most of the big Firewire companies have taken a very active role in the creation of the USB3 Vision standard. This certainly sends a message. And the table above simply confirms that Firewire is going to get squeezed between GigE Vision and USB3 Vision. Firewire will survive for a long time because of its large deployed base, but I predict that its market share will decline steadily.
Finally, GigE Vision is also going to suffer from the arrival of USB3 Vision, but not as much as Firewire and Camera Link BASE. From a bandwidth perspective, GigE Vision is at a disadvantage. But it has other characteristics (long cable, network topology, installed base) that make it suitable for many applications. And the migration path to 10 GigE in a few years provides an incentive to favor Ethernet-based technologies.
One thing not clearly highlighted by this table is that the lower-end of the frame grabber industry is once again under attack. After Firewire and GigE Vision, now USB3 Vision raises the bar of frame grabber-less systems to a 350 MB/s acquisition data rate.
So what is my conclusion? Simply that USB3 Vision will be an outstanding camera interface for most applications that can tolerate short cables – and in my view, the majority of systems we see out there today!
Till next time!