Google has applied for a patent on a surgical system for removing biological tissue with a laser that delivers electromagnetic radiation.

The patent was published yesterday. Google first applied for it in May 2014, long before establishing the umbrella company Alphabet, which includes the standalone life sciences company that was spun out of the Google X laboratory.

Here’s how the technology is described in the patent’s abstract:

An active tracking system includes an imager configured to image the temperature of a biological tissue and a heating laser configured to heat regions of the biological tissue. The imager locates high-temperature regions of the biological tissue and the heating laser is controlled to point toward target regions of the biological tissue based on the located high-temperature regions. The active tracking system can be used to control a heating laser to continuously heat a target region of a biological tissue even when the target region moves relative to the heating laser. The active tracking system could allow one or more target regions of a biological tissue to be `tagged` with heat by the heating laser and to be tracked even when the one or more target regions move relative to the heating laser. Devices and methods for operating such active tracking systems are also provided.

This type of technology certainly falls into the “bets” category (far outside the classic realm of Google, which includes web search, web browsing, YouTube, and Gmail). Just like the Google experiment¬†Project Loon, for broadcasting Internet from a balloon, or the Google self-driving car, this laser surgery technology might not pay off for 10 years or more.

Of course, the filing does not guarantee that Alphabet will ever release technology that’s anything close to the system documented in this patent. (Remember the Google contact lens for monitoring blood glucose levels?)

Still, there aren’t many companies who can say they’re attempting to advance a category of medical devices for ridding people of cancer, among other things, as a side project. Google — well, Alphabet now — is one of them.