"We've been working on this product for a while, and I just didn't want to miss today," Jobs said at the San Francisco event. "Thank you for having me."
The next-generation tablet computer has a faster processor than the original iPad's. As expected, it comes with two cameras for taking photos and video chatting. The battery life will be the same as the original -- about 10 hours of "on" time and a month on standby.
The iPad 2 is also thinner -- 8.8 millimeters instead of the current 13.4 millimeters.
"The new iPad 2 is actually thinner than your iPhone 4," Jobs said.
The new iPads will cost the same as the originals -- $499 to $829, depending on storage space and whether or not they can connect to the Internet over a cellular network. In the U.S., the iPad 2 will work on AT&T Inc. and Verizon Wireless.
Apple also introduced a new accessory for the iPad that will let people connect the tablet to high-definition televisions, so they can watch videos up to 1080p in resolution on the bigger screen. The $39 part plugs into the iPad's charging port and connects to an HDMI cable.
After its March 11 U.S. launch, the iPad 2 goes on sale March 25 in at least 26 other markets, including Mexico, New Zealand, Spain and other European countries.
Jobs announced in January that he would take a third leave of absence to focus on his health. In the last decade, Jobs, 56, has survived a rare but curable form of pancreatic cancer and undergone a liver transplant.
Chief Operating Officer Tim Cook has been running day-to-day operations.
In 2009, Jobs said in advance that he would take a six-month medical leave; this time, the company did not specify when he would return. The last time Steve Jobs went on medical leave, marketing chief Phil Schiller was the main presenter at product launch events.