On the heels of its major merger announcement with T-Mobile, AT&T has quietly made another splash in the smartphone world with a 3D phone.

The Dallas-based company announced two new smartphones to its portfolio, one of which has a glasses-free 3D display. AT&T says the LG Thrill 4G, a version of the Optimus 4G, is the first U.S. smartphone that will feature a glasses-free 4.3-inch stereoscopic 3D display plus 4G speed capability on the nation's fastest mobile broadband network.               

Users of the LG Thrill will be able to shoot 3D video and 3D stills with the dual 5-megapixel stereoscopic camera. The phone will also feature 3D content via LG 3D Space, which houses 3D games, video clips and images. The 3D camera will have 720p resolution and 2D at 1080p quality.

The Android 2.2 based phone will run on a dual-core, dual-channel 1 GHz processor with 16 GB of memory.

Along with the LG Thrill, AT&T is also bringing aboard the HTC HD7S, a Windows Phone 7 device. It will come with a 4.3-inch, WVGA, super LCD display, 1 GHz processor and 5-megapixel camera with dual-LED flash.

AT&T customers know that we offer the best lineup of cutting-edge smartphones in the country.  Our first 3D phone plus a new, leading Windows Phone underscore our commitment to continue to offer the best, Jeff Bradley, senior vice president, Devices, AT&T Mobility and Consumer Markets, said in a statement. 2011 is going to be another landmark year for us with more best-in-class devices.