illustration photo |
The benchmark Nikkei index at the Tokyo Stock Exchange gained 133.15 points to 9,691.84. The Topix index of all first section shares was up 0.75 per cent or 6.23 points at 839.87.
The headline index kept its gains even after ratings agency Standard & Poor's lowered its outlook on Japanese sovereign debt to negative from stable, citing last month's quake-tsunami disaster.
The move drove up the dollar against the yen, a trend that generally helps Japanese exporters.
Most Asian shares were lifted by the sharp overnight gains of Wall Street shares on the back of strong company results.
The Dow Jones Industrial Average leapt 115.49 points (0.93 per cent) to finish at 12,595.37, a near three-year high.
But many investors took a wait-and-see stance before a two-day Federal Reserve meeting was due to wind up on Wednesday.
"The market awaits comments from the US Federal Reserve this week, ahead of closely-watched domestic earnings," said Hiroichi Nishi, equity general manager at Nikko Cordial Securities.
Sony fell 2.02 per cent to 2,366 yen following news that it had fallen victim to hackers.
The firm is warning that the personal data of about 77 million users of its PlayStation Network, which connects people online, had been stolen.
Canon shot up 7.01 per cent to 3,740 yen despite the high-tech giant Tuesday announcing that its profit fell for the January-March quarter while it cut its full-year earnings outlook because of the March 11 quake.
Analysts said the company's business results, excluding the disaster impact, were strong.
"If the earthquake hadn't hit, Canon would have significantly raised its earnings outlook," said Monex market analyst Toshiyuki Kanayama.
The dollar, which in the morning had been at 81.44 yen, rose to 81.83 yen after the S&P announcement, from 81.55 in New York late Tuesday.
The euro gained to $1.4688 from $1.4636 in New York and to 120.02 yen from 119.38 yen.
What the stars mean:
★ Poor ★ ★ Promising ★★★ Good ★★★★ Very good ★★★★★ Exceptional