Optimal charging and energy conserving apparatus and method for controlling camera functions in an automatic flash camera
AssigneeNikon Corporation
InventorYoshikazu Iida
Life of this patent
Estimating the term…
Abstract
An autofocusing camera allows a distance measurement operation even if the electric charge amount accumulated in the condenser does not reach a predetermined value when a picture to be taken does not require flash (strobe) light emission.
Claims17
A camera having a power switch, the camera comprising:
- a distance measurement circuit that measures a distance between the camera and a photographic object;
- a condenser that when charged stores sufficient electric charge for a flash lighting of the photographic object during exposure;
- an electric charge amount circuit that determines whether the condenser has been charged to a predetermined amount prior to the distance measurement by the distance measurement circuit, the electric charge amount circuit prohibiting the distance measurement circuit from measuring the distance between the camera and the object when the electric charge amount stored in the condenser does not reach the predetermined amount;
- and
- a light emitting determination circuit that selects one of emitting the flash lighting during exposure and preventing the flash lighting during exposure, the distance measurement circuit measuring the distance between the camera and the object when the light emitting determination circuit prevents the flash lighting during exposure regardless of the determination by the electric charge amount circuit, the condenser charging after actuation of the power switch and prior to the light emitting determination circuit selecting the one of emitting and preventing.
A camera having a power switch, the camera comprising:
- distance measurement means for measuring the distance between the camera and a photographic object;
- charge storage means for storing sufficient charge for a flash lighting of the photographic object during exposure, the charge storage means storing charge at least when the power switch is actuated;
- charge amount determination means for determining whether the charge storage means has been charged to a predetermined amount prior to the distance measurement means measuring the distance between the camera and the object, the charge amount determination means prohibiting the distance measurement means from measuring the distance between the camera and the object when the electric charge amount accumulated in the charge storage means does not reach the predetermined amount;
- and
- light emitting determination means for selecting one of emitting the flash lighting during exposure and preventing the flash lighting during exposure, the light emitting determination means selecting the one of emitting and preventing after the power switch is actuated to store charge in the charge storage means and prior to the distance measurement means measuring the distance between the camera and the object, the distance measurement means measuring the distance between the camera and the object when the light emitting determination means prevents the flash lighting during exposure regardless of the determination by the charge amount determination means.
A camera for use with an electronic flash device having an electronic flash tube that emits flash lighting to illuminate an object to be photographed, a power switch, a condenser electrically connected to the electronic flash tube, a charge determination circuit that determines whether the condenser is completely charged and a charging device that charges the condenser at least on actuation of the power switch, the condenser when completely charged carrying sufficient charge for the flash lighting, the camera comprising:
- a manual switch;
- a distance measurement device that measures the distance between the camera and the object based on the operation of the manual switch;
- a light emitting determination device that determines one of emitting flash lighting from the electronic flash tube and preventing flash lighting from the electronic flash tubes;
- and
- a controller that prohibits the distance measurement by the distance measurement device when the charge determination device detects that the condenser is not completely charged, the controller allowing the distance measurement device to measure the distance when the light emitting determination device determines to prevent flash lighting from the electronic flash tube regardless of the condenser charge.
A method for operating a flash camera having a condenser that stores charge for a flash lighting of an object, a first power switch and a second manually operable switch, the method comprising the steps of:
- charging the condenser upon actuation of the first switch;
- interrupting the charging step upon actuation of the second switch;
- determining whether the flash lighting will be used;
- performing a distance measurement between the camera and the object if the flash lighting will not be used;
- and
- performing the distance measurement between the camera and the object if the flash lighting will be used and the condenser is charged to at least a predetermined value.
Dependencies are inferred from the claim text.