Title:
LIGHT QUANTITY CONTROLLER FOR CAMERA
Document Type and Number:
Japanese Patent JP3158231
Kind Code:
B2
Abstract:
PURPOSE: To make a lens stop device small in size, light in weight and reduced in product cost.
CONSTITUTION: By rotating either one of lens barrels 13 with a lens member 11, a wing 17c formed on a face opposite to the lens barrel 13 is slid in a pump room 17b so as to push out light shielding fluid 16 in the pump room 17b, and then, the fluid 17 is injected into a hollow part 15. The side crosssectional shape of the hollow part 15 is formed so that the distance between lens faces facing each other become narrower as it goes from the peripheral part closer to the center, then, a part of the injected light shielding fluid 16 is moved from the peripheral part of the hollow part 15 to the central part by the surface tension of the fluid, and then, a nearly cylindrical light transmission part 16a is formed at the central part, and the light shielding part 16b filled with the light shielding fluid is formed at the peripheral part. By increasing the amount of the injected light shielding fluid 16, the area of the light shielding part 16b is enlarged and also the area of the light transmission part 16a is reduced, so that the quantity of light passing through the light transmission part 16a is controlled by changing the amount of the injected light shielding fluid 16.
Inventors:
Tomoaki Tamura
Application Number:
JP11615693A
Publication Date:
April 23, 2001
Filing Date:
May 18, 1993
Export Citation:
Assignee:
Konica Corporation
International Classes:
G02B26/02; G03B9/02; (IPC1-7): G03B9/02
Attorney, Agent or Firm:
Fujio Sasashima