SAN FRANCISCO (Reuters) -Amazon ( AMZN ) on Tuesday unveiled a refreshed lineup of devices optimized for home security and its new artificial intelligence-infused Alexa+ voice assistant.

At an event in New York, Amazon ( AMZN ) showed off Echo speakers, Fire TV streaming devices, a new Kindle reader and improved Ring and Blink cameras.

Amazon ( AMZN ) is trying to drive interest in the new Alexa, which it spent years updating with AI for better personalization and a more conversational tone. The effort carries significant weight as Amazon ( AMZN ) has spent billions on Alexa with the aim of making the money-losing service profitable. 

The Seattle firm said its new Echos, including smaller Dots and Show devices with screens that range from $99 to $219, will be enabled to work with Alexa+ and feature new silicon chips for faster processing.

Amazon ( AMZN ) also rolled out improved cameras for its Ring devices for better home security, including facial recognition to help ward off unwanted visitors. The head of Ring, Jamie Siminoff, said blurry images can make it more difficult to survey a scene outside one's home.

The new Ring cameras, available later this year, will also be enabled with Alexa+ allowing the devices, through the use of AI, to help make decisions like whether a visitor is delivering a package or casing someone's house for intrusion. They will be priced from $60 to $350 depending on their utility and camera quality.

"It's about knowing immediately whether your visitor is someone you know or someone you've never seen before," said Siminoff, whom Amazon ( AMZN ) brought back to the company earlier this year. 

There are also new Blink cameras with higher resolution for better monitoring inside and outside one's home, Amazon ( AMZN ) said.