The Endoscope Camera in a Pill

The tiniest endoscope yet takes 30 two-megapixel images per
second and offloads them wirelessly. See how it works inside
the body in an animation.

Pop this pill, and eight hours later, doctors can examine
a high-resolution video of your intestines for tumors and
other problems, thanks to a new spinning camera that captures
images in 360 degrees. Developed by the Japanese RF System
Lab, the Sayaka endoscope capsule enters clinical trials in
the U.S. this month.

How the Pill Films Your Innards

Down the Hatch
The patient gulps down the capsule, and the digestive process
begins. Over the next eight hours, the pill travels passively
down the esophagus and through roughly 20 to 25 feet of
intestines, where it will capture up to 870,000 images. The
patient feels nothing.

Power Up
The Sayaka doesn’t need a motor to move through your gut, but
it does require 50 milliwatts to run its camera, lights and
computer. Batteries would be too bulky, so the cam draws its
power through induction charging. A vest worn by the patient
contains a coil that continuously transmits power.

Start Snapping
When it reaches the intestines, the Sayaka cam begins
capturing 30 two-megapixel images per second (twice the
resolution of other pill cams). Fluorescent and white LEDs in
the pill illuminate the tissue walls.

Spin For Close-Ups
Previous pill cameras place the camera at one end, facing
forward, so the tissue walls are visible only in the periphery
of their photos. Sayaka is the first that gets a clearer
picture by mounting the camera facing the side and spinning
360 degrees so that it shoots directly at the tissue walls.
As the outer capsule travels through the gut, an electromagnet
inside the pill reverses its polarity. This causes a permanent
magnet to turn the inner capsule and the image sensor 60
degrees every two seconds. It completes a full swing every 12
seconds—plenty of time for repeated close-ups, since the
capsule takes about two minutes to travel one inch.

Offload Data
Instead of storing each two-megapixel image internally,
Sayaka continually transmits shots wirelessly to an antenna
in the vest, where they are saved to a standard SD memory
card.

Deliver Video
Doctors pop the SD card into a PC, and software compiles
thousands of overlapping images into a flat map of the
intestines that can be as large as 1,175 megapixels. Doctors
can replay the ride as video and magnify a problem area up to
75-fold to study details.

Leave the Body
At around $100, the cam is disposable, so patients can simply
flush it away.