Japan's large manufacturers turned more confident about their business in the April-June quarter, marking the first improvement in three quarters, according to the Bank of Japan's "tankan" business sentiment survey released Friday.

According to the closely watched quarterly survey, the business confidence index for large manufacturers was 18, up from 14 the previous quarter. It is the first rise since the July-September quarter last year.

The index represents the percentage of companies reporting good conditions minus those reporting the opposite.