Shares of Sony Corp fell to their lowest in nearly four months on Friday (Nov. 20) after the electronics maker's new business strategy failed to convince investors it could deliver strong profit growth.

Sony, which is heading for its second straight annual loss, said on Thursday it would launch 3D TVs and networked products and services as part of a plan to boost its operating profit margin to 5% in the year to March 2013.

The 5% target had originally been set by CEO Howard Stringer in 2005 for the business year to March 2008. It narrowly missed the target that year before falling into the red on the economic slowdown and tough competition.

Market players remain sceptical whether Sony can achieve its goal of turning its video game and TV operations profitable next year as it struggles to compete with overseas rivals such as South Korea's Samsung Electronics Co Ltd. Sony's TV business is in its sixth-consecutive year of losses as it grapples with a firmer yen and intensified competition from Samsung and LG Electronics Inc.

Shares in Sony closed down 2.4% at 2,410 yen ($27.10) after earlier hitting 2,375 yen ($26.71), their lowest since July 29.

The maker of Cyber-shot cameras and PlayStation games shed jobs, closed plants and sold non-core assets following the global downturn to cut costs, and investors were awaiting a convincing growth strategy from management ahead of Thursday's announcement.

Next year Sony plans to launch a new online service to distribute entertainment content such as movies, music and books to network-capable TVs, Blu-ray players and other devices, in a move to capitalise on its strong presence both in hardware and entertainment industries.

Sony Executive Vice President Kazuo Hirai also said on Friday that the company was confident that sales of its PlayStation 3 game console will hit its target of 13 million units this financial year.

"We need to see how the holiday season shakes out. But based on all the data we've seen so far, and based on what we know [about] how the holiday is going to ramp up, 13 million looks like a pretty solid number," he said.

The company pioneered the mobile music market 30 years ago with its Walkman and once ruled the global television industry in the era of box TVs, but it is now struggling to keep pace with nimbler South Korean rivals and innovative U.S. IT companies.

Its portable music players have been in the shadow of Apple Inc's iPod in recent years, while, in the LCD TV market, its Bravia models have lagged a long way behind Samsung, and now LG is threatening Sony's No.2 position.

Samsung accounted for 22.5% of global LCD TV revenues in July-September, followed by Sony's 12.1 percent and LG's 11%, according to data from research firm DisplaySearch.

In an effort to improve profits at its TV operations, Sony plans to have 40% of its LCD TVs assembled by outside manufacturers in the next business year starting April 2010, up from 20% this year.