TOKYO, April 18 (Reuters) - Japan's Nikkei share average fell on Thursday, putting it on course for its longest losing streak since October, as chip-sector shares followed global peers lower.

The Nikkei was down 0.48% at 37,779.25 as of 0141 GMT, heading for a fourth straight day of declines. It has fallen 4.35% so far this week, on track for its worst week since December 2022.

Semiconductor shares and other tech stocks sank after Dutch computer chip equipment maker ASML announced new bookings on Wednesday that fell well short of analyst estimates.

Japanese chip-making equipment giant Tokyo Electron slid 1.29% to be among the Nikkei's biggest drags. Artificial intelligence-focused startup investor SoftBank Group dropped 3.35% to be another major weight on the index.

Energy shares also fell sharply amid a decline in crude oil prices.

However, the Nikkei managed to pare some early losses as dip buyers emerged.

The broader, less tech-heavy Topix reversed small early losses to be up 0.19%. A subindex of value shares gained 0.27% while growth stocks added 0.06%.

For the year, the Nikkei remains up 13.22%.

"The Japanese market has been strong since the start of the year, so it's natural for some investors to take profits," leading to weakness this week, said Kenji Abe, an equities strategist at Daiwa Securities.

"But I'm still sanguine about the outlook for Japanese equities because earnings are quite robust," Abe added, predicting that dips below 38,000 in the Nikkei will attract "bottom fishing," and over the next year, the index is likely to climb to 43,000.

The Nikkei rose to a record 41,087.75 on March 22, and had declined 7.61% from that point as of Wednesday's close.

The earnings season began earlier this month with retailers headlining early reports. Tech names are due from next week, although the bulk of company announcements come in mid-May. (Reporting by Kevin Buckland; Editing by Janane Venkatraman )