Pentax Corp., Japan’s oldest single-lens reflex camera maker, wants to double its annual operating profit in three years, a company official said on Thursday.

The firm is under pressure to increase its profit by Tokyo-based asset manager Sparx Group Co., its biggest shareholder, Kyodo News Service reported.

The firm cut short a planned merger with bigger rival Hoya Corp. in April, although Sparx criticized its decision.

Instead, Pentax will look to raise its operating profit to 10 billion yen ($84 million) by the end of 2009, up from an estimated 5.5 billion yen($46 million) for the fiscal year that ended in March, according to the firm.

Sparx, which owns a stake of about 30 percent, criticized Pentax for not merging with Hoya. After scrapping the merger, Sparx pressured Pentax to show alternative options to raise the firm’s value.

Pentax hopes to beef up its three main business segments - digital cameras, optical components and medical products - and focus on developing new digital cameras for general consumers rather than products for professional photographers.

According to Jiji Press,Pentax is also considering selling its head office building in Tokyo to help consolidate operations.