Camera

Details Camera Camera

1999-10-25

2001-05-01

Perkey, W. B. (Department: 2851)

Photography

Attitude sensing

Reexamination Certificate

active

06226458

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a camera having an attitude detecting function and arranged to perform control according to the attitude of the camera.
2. Description of Related Art
FIG. 11
shows a single-lens reflex camera. The single-lens reflex camera is provided with a main mirror
104
for guiding an object image, i.e., information on an object to be photographed, from a photo-taking lens
103
to an eyepiece
107
and a light measuring sensor
108
through a viewfinder optical system
106
. The main mirror
104
is swingably disposed between the photo-taking lens
103
and a shutter
110
which is arranged to control an exposure amount in exposing a film
111
to the object image coming from the photo-taking lens
103
. When the camera measures light while the camera user is observing the object before taking a shot, the main mirror
104
is set at an observing position, i.e., at an entrance position within a photo-taking optical path where the object image from the photo-taking lens
103
can be guided to the eyepiece
107
.
A central part of the main mirror
104
is arranged to be a half mirror. A submirror
105
is swingably carried by the main mirror
104
. A part of the object information from the photo-taking lens
103
passes through the half mirror part of the main mirror
104
to be guided to a focus detecting device
112
through the submirror
105
.
To prevent the object image from the photo-taking lens
103
from being eclipsed by the main mirror
104
and the submirror
105
in taking a shot, the mirrors
104
and
105
are swung upward into a retracted position which is located outside of the photo-taking optical path.
After completion of an exposure, the main mirror
104
and the submirror
105
are moved back to the observing position to permit observation of the object and light-measuring and focus-detecting actions for the next shot.
The main mirror
104
is urged to move downward by a spring (not shown). When a member which is pushing the main mirror
104
upward is released from the pushing action after completion of an exposure, the main mirror
104
is caused by the urging force of the spring to swing downward back to the observing position. Following the downward motion of the main mirror
104
, the submirror
105
also moves back to the position shown in FIG.
11
.
According to the procedures for the sequence of actions of the camera to be performed after an exposure, the light-measuring and focus-detecting actions, etc., for the next shot are allowed to be performed after the lapse of a predetermined period of time (mirror stabilization time) from the commencement of downward movement of the mirrors
104
and
105
from the retracted position to the observing position. The predetermined period of mirror stabilization time is set at a length of time found through tests to be required after the commencement of the downward movement of the mirrors from the retracted position to the observing position and before they cease to bounce on stoppers to lay at rest.
However, since each of the mirrors has a certain amount of mass, the length of time to be set as the mirror stabilization time varies with the posture or attitude of the camera. In other words, the mirror stabilization time varies according to the relation of the urging direction of a spring force to the direction of gravity. In view of this, a camera disclosed, for example, in Japanese Laid-Open Patent Application No. HEI 6-74766 is arranged to have the mirror stabilization time selectable from among a plurality of periods set according to the various attitudes of the camera.
BRIEF SUMMARY OF THE INVENTION
In accordance with one aspect of the invention, there is provided a camera comprising a movable mirror which moves between a mirror-down position and a mirror-up position, an attitude detecting device which detects an attitude of the camera, and a control circuit in which a plurality of periods of stabilization time of the movable mirror are set and which changes over the stabilization time of the movable mirror among the plurality of periods according to a result of detection provided by the attitude detecting device, wherein, if the attitude of the camera has changed in process of a continuous photo-taking operation, the control circuit keeps the stabilization time of the movable mirror set at the time of start of the continuous photo-taking operation without changing over the stabilization time of the movable mirror, so that it is possible to continue the photo-taking operation at a fixed interval during process of the continuous photo-taking operation.
The above and other aspects and features of the invention will become apparent from the following detailed description of a preferred embodiment thereof taken in connection with the accompanying drawings.


REFERENCES:
patent: 5659805 (1997-08-01), Furlani et al.

Affiliated with

Also associated with

Rating

Camera does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Camera, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Camera will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2484333