Shutter

Abstract

Abstract PURPOSE: To obtain optional shutter speed and to attain a quick shutter motion by opening a liquid crystal shutter after a mechanical shutter is opened, and closing the mechanical shutter after the liquid crystal shutter is closed or the moment it was closed. CONSTITUTION: The behind lens shutter (mechanical shutter) 4 mechanically opening and closing plural vanes is provided behind a lens group 2, and the liquid crystal shutter 5 employing a ferromagnetic liquid crystal 9 is provided behind the mechanical shutter 4. An action circuit is provided inside a camera, and a control part 17 is constituted of the action circuit, a control circuit 13, a mechanical shutter driving circuit 14 and a liquid crystal shutter driving circuit 15. The control circuit 13 calculates the release time of the mechanical shutter 4 from that of the liquid crystal shutter 5, and sets the release time of the mechanical shutter longer than that of the liquid crystal shutter. The driving circuit 15 generates a DC pulse with prescribed pulse width in a prescribed timing, applies it on the liquid crystal shutter 5, and opens and closes the shutter. Thus a quick shutter speed and optional shutter speed are obtained. COPYRIGHT: (C)1989,JPO&Japio

Inventors

• 👤 Jun Nakanowatari
• 👤 Yoshimi Kamijo

Bibliographic Details