SAN FRANCISCO (Reuters) - Lightmatter, a startup valued at $4.4 billion, on Monday released two pieces of technology aimed at speeding up the connections between artificial intelligence chips.

Instead of moving information between computer chips as electrical signals, Lightmatter's technology uses optical connections and what are known as silicon photonics to move the information using light.

Mountain View, California-based Lightmatter has raised $850 million in venture funding to date as such optical technologies have kicked off a wave of investments in Silicon Valley amid a search for better ways to string together chips to power chatbots, image generators and other AI applications.

AI chip firms like Advanced Micro Devices ( AMD ) have demonstrated the use of optical technologies packaged together with their chips. Nvidia ( NVDA ) earlier this month introduced optical technology in some of its networking chips, though its CEO said the technology is not yet mature enough to use in all of its chips.

Lightmatter on Monday introduced two new products that are designed to be packaged together with AI chips. One is called an interposer, a layer of material that the AI chip sits atop to connect to neighboring chips that also sit atop the interposer. The other is a small tile called a "chiplet" that can be placed on top of an AI chip. 

Lightmatter said its interposer will be released in 2025 and the chiplet in 2026. The interposer is manufactured by GlobalFoundries. 

(Reporting by Stephen Nellis in San Francisco; Editing by Leslie Adler)