What's inside TransLink's Compass Cards?
A university professor visiting Vancouver from California was so enamored with the tiny technology inside TransLink’s Compass Cards that he decided to dissect one of the fare tickets — and documented the process.
In an online post, William Grover described his surprise at realizing that TransLink’s new paper tickets were “no dummy” cards.
“I was surprised when I reached the turnstile and found no place to insert the paper ticket. Instead there was a target for tapping a smart card. All the smart cards I’ve seen are plastic, so it took me a second to realize that my disposable paper ticket might harbour smart insides,” Grover, a bioengineering professor at University of California, wrote.
“Plastic smart cards with RF antennas are nothing new, but seeing these electronics sandwiched into a normal sheet of paper was impressive.”
He decided to take one home for further examination, first peeling off the top and bottom layers of paper to reveal a thin sheet of plastic with an antenna looping around a “tiny brown blob” under the M in Compass.
After plucking out the bit and separating the tech from the glue, the chip’s surface was fully visible — at least under a microscope.
“Without the microscope, the brains of this smart card are indistinguishable from a single grain of pepper. And when carefully placed on a penny, the silicon chip fits into the zero in the year 2000,” he wrote.
Reached by email, Grover said he wanted to document the process to share with other educators.
“My own research involves developing new medical diagnostics, and often we’re trying to make these diagnostics as cheap as possible so that large numbers of people can use them. So I guess that’s why the Compass Card caught my interest — it packs some sophisticated electronics into a piece of paper that’s so cheap it’s disposible,” he said.
To take the photos, Grover said he used his home microscope with a built-in camera.
TransLink, in a statement, said the single-use tickets use Mifare Ultralight technology, which is a lower-storage version of the tech used in plastic Compass Cards.
“This type of processor is commonly used in the transit industry ... We source the transit tickets from a variety of manufacturers, while the microchips are produced by NXP Semiconductors,” TransLink said.
“The plastic Compass Cards use a different chip — the Mifare DESfire EV1.”