Finder device
AssigneeFUJIFILM Corporation
InventorsMakoto Kobori, Shunsuke Miyagishima, Hiroki Saito
Life of this patent
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Abstract
Provided is a finder device capable of preventing dust on a display surface of a display element and reducing an influence of heat which is generated from the display element on an optical system. An electronic view finder (EVF) includes: an optical system that includes a display element, a first lens group disposed in order from the display element side, and a second lens group; a first holding frame that holds the display element and the first lens group to seal a space between the display element and the first lens group; a second holding frame that holds the second lens group; and a diopter adjustment unit that adjusts a diopter by integrally moving the display element and the first lens group relative to the second lens group.
Claims13
A finder device comprising:
- a display element;
- an optical system that includes at least a first lens group and a second lens group in order from a side of the display element;
- a first lens group holding member that holds the first lens group to seal a space between the display element and the first lens group;
- a second lens group holding member that holds the second lens group;
- and
- a diopter adjustment unit that adjusts a diopter by integrally moving the display element and the first lens group relative to the second group,
- wherein the first lens group satisfies the following conditional expression:
- 0.001<|f20−f40l/fe<0.05,
- where
- f20 is a focal length (millimeter) of the first lens group at a temperature of 20 degrees, f40 is a focal length (millimeter) of the first lens group at a temperature of 40 degrees, and
- fe is a composite focal length (millimeter) of the first lens group and the second lens group in a case where a temperature is 20 degrees and a diopter is −1 dpt.
A finder device comprising:
- a display element;
- an optical system that includes at least a first lens group and a second lens group in order from a side of the display element;
- a first lens group holding member that holds the first lens group to seal a space between the display element and the first lens group;
- a second lens group holding member that holds the second lens group;
- and
- a diopter adjustment unit that adjusts a diopter by integrally moving the display element and the first lens group relative to the second lens group,
- wherein a member, which is interposed between the display element and the first lens group, satisfies the following conditional expression:
- jFave<0.5,
- where
- jFave is an average value of thermal conductivities (W/mK) of the member which is interposed between the display element and the first lens group.
Dependencies are inferred from the claim text.