A new microcomputer has been created by researchers at the University of Michigan. The millimeter-scale computing system can store up to a week volume of data and can reside on something as small as a human eye. The computer, called the Phoenix chip, is just over one cubic millimeter in size and was designed to monitor eye pressure in glaucoma patients.

"This is the first true millimeter-scale complete computing system," Dennis Sylvester, a professor at the school and one of the researchers on the project, said in a statement.

The computer inner parts include an ultra low-power microprocessor, a pressure sensor, memory, a thin-film battery, a solar cell and a wireless radio with an antenna that can transmit data to an external reader device held near the eye.

The chip uses a power gating architecture with an extreme sleep mode that powers the computer up briefly every 15 minutes to take readings. By remaining in sleep mode most of the time, the chip sips power, averaging 5.3 nanowatts every time it turns on.

The Phoenix chip's photovoltaic system requires 10 hours of indoor light or 1.5 hours of sunlight to fully charge the battery.

The data is transferred to a reader as the chip’s micro radio auto-tunes to whatever wireless frequency is available. The data can then be used as part of an electronic medical record for treatment.

The research is conducted by three faculty members in the University of Michigan Department of Electrical Engineering and Computer Science.