Electronic camera having an automatic electric flash function

Claim 2

An electronic camera comprising: light emission means for emitting a light to an object, said light emission means performing a preliminary light emission and a main light emission; an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal; amplifying means for amplifying the electrical image signal; and setting means for setting a gain for said amplifying means and an amount of light for the main light emission, based on the electrical image signal, said setting means being structured to operate exclusively below a camera shake limitation parameter associated with said electronic camera.

Claim 3

The camera according to claim 1 , wherein said setting means increases the gain when the electrical image signal fails to have a desired magnitude even if an amount of the light for the main light emission is set to a maximum.

Claim 4

The electronic camera according to claim 1 , further comprising photograph mode selecting means for selecting a desirable one of a plurality of photograph modes, wherein said setting means sets the gain in accordance with the photograph mode selected by said photograph mode selecting means.

Claim 5

The electronic camera according to claim 1 , wherein the gain is not changed when a difference or a ratio, in amount between the light reflected from the object during the preliminary light emission, and the light coming from the object when no light is emitted to the object is not more than a predetermined value.

Claim 6

The electronic camera according to claim 1 , wherein said setting means generates an alarm when the gain is changed in the main light emission.

Claim 7

The electronic camera according to claim 2 , further comprising photograph mode selecting means for selecting a desirable one of a plurality of photograph modes, wherein said setting means sets the gain in accordance with the photograph mode selected by said photograph mode selecting means.

Claim 8

The electronic camera according to claim 2 , wherein the gain is not changed when a difference or a ratio, in amount between the light reflected from the object during the preliminary light emission, and the light coming from the object when no light is emitted to the object is not more than a predetermined value.

Claim 9

The electronic camera according to claim 2 , wherein said setting means generates an alarm when the gain is changed in the main light emission.

Claim 10

The electronic camera according to claim 3 , wherein the gain is not changed when a difference or a ratio, in amount between the light reflected from the object during the preliminary light emission, and the light coming from the object when no light is emitted to the object is not more than a predetermined value.

Claim 11

The electronic camera according to claim 3 , wherein said setting means generates an alarm when the gain is changed in the main light emission.

Claim 12

The electronic camera according to claim 4 , wherein said setting means generates an alarm when the gain is changed in the main light emission.

Claim 13

An electronic camera comprising: light emission means for emitting a light to an object in present amounts, said light emission means performing a preliminary light emission and a main light emission; an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal; amplifying means for amplifying the electrical image signal, with a preset gain; photograph means for comparing an amount of light received when no light is emitted to the object, which is obtained from the electrical image signal, with a predetermined value to evaluate the amount of light received; operating means for operating the light emission means when an evaluation result shows that said received light amount is insufficient; optimum setting value calculating means for obtaining at least one of the main light emission amount and the gain from the amount of the light received when no light is emitted to the object and the amount of the light received during the preliminary light emission; and setting means for setting at least one of the light emission amount obtained during the main light emission and the gain, as a set value, said setting means being structured to operate exclusively below a camera shake limitation parameter associated with said electronic camera.

Claim 14

An electronic camera comprising: light emission means for emitting a light to an object in present amounts, said light emission means performing a preliminary light emission and a main light emission; an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal; amplifying means for amplifying the electrical image signal, with a preset gain; photograph means for comparing an amount of light received when no light is emitted to the object, which is obtained from the electrical image signal, with a predetermined value to evaluate the amount of light received; operating means for operating the light emission means when an evaluation result shows that said received light amount is insufficient; optimum setting value calculating means for obtaining at least one of the main light emission amount and the gain from the amount of the light received when no light is emitted to the object and the amount of the light received during the preliminary light emission; and setting means for setting at least one of the light emission amount obtained during the main light emission and the gain, as a set value, said setting means being structured to operate exclusively below a camera shake limitation parameter associated with said electronic camera.

Claim 15

An electronic camera comprising: light emission means for emitting a light to an object in present amounts, said light emission means performing a preliminary light emission and a main light emission; an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal; amplifying means for amplifying the electrical image signal, with a preset gain; photograph mode selecting means for selecting a desirable one of a plurality of photograph modes; photograph means for comparing an amount of light received when no light is emitted to the object, which is obtained from the electrical image signal, with a predetermined value to evaluate the amount of light received; operating means for operating the light emission means when an evaluation result shows that said received light amount is insufficient; optimum setting value calculating means for obtaining at least one of the main light emission amount in said selected photograph mode and the gain from the amount of the light received when no light is emitted to the object and the amount of the light received during the preliminary light emission; and setting means for setting at least one of the light emission amount obtained during the main light emission and the gain, as a set value, said setting means being structured to operate exclusively below a camera shake limitation parameter associated with said electronic camera.

Claim 16

An electronic camera comprising: light emission means for emitting a light to an object in present amounts, said light emission means performing a preliminary light emission and a main light emission; an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal; amplifying means for amplifying the electrical image signal, with a preset gain; photograph mode selecting means for selecting a desirable one of a plurality of photograph modes; photograph means for comparing an amount of light received when no light is emitted to the object, which is obtained from the electrical image signal, with a predetermined value to evaluate the amount of light received; operating means for operating the light emission means when an evaluation result shows that said received light amount is insufficient; optimum setting value calculating means for obtaining at least one of the main light emission amount in said selected photograph mode and the gain from the amount of the light received when no light is emitted to the object and the amount of the light received during the preliminary light emission; and setting means for setting at least one of the light emission amount obtained during the main light emission and the gain, as a set value, said setting means being structured to operate exclusively below a camera shake limitation parameter associated with said electronic camera.

Claim 17

The electronic camera according to claim 13 , further comprising emission amount control means for controlling a light emission amount during the preliminary light emission and the main light emission to a set value; and gain control means for controlling the gain of said amplifying means to a set value.

Claim 18

In a method of controlling an electric flash photography performed by an electronic camera comprising light emission means for emitting a light to an object, said light emission means performing a preliminary light emission and a main light emission, an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal, and amplifying means for amplifying the electrical image signal with a preset gain, said method comprising: selecting a desirable one of a plurality of photographing modes; comparing an amount of light received when no light is emitted to the object, which is obtained from the electrical image signal, with a predetermined value to evaluate the amount of light received; operating the light emission means when an evaluation result shows that the received light amount is insufficient; obtaining at least one of the main light emission amount and the gain from the amount of the light received when no light is emitted to the object and the amount of the light received during the preliminary light emission; setting at least one of the light emission amount obtained during the main light emission and the gain, as a set value, while maintaining the operation of the electronic camera below a camera shake limitation parameter thereof; and photographing the object with the main light emission amount set and the gain set.

Claim 19

In a method of controlling an electric flash photography performed by an electronic camera comprising light emission means for emitting a light to an object, said light emission means performing a preliminary light emission and a main light emission, an imaging element for receiving a light reflected from the object during the preliminary light emission and converting the light into an electrical image signal, and amplifying means for amplifying the electrical image signal with a preset gain, said method comprising: selecting a desirable one of a plurality of photographing modes; comparing an amount of light received when no light is emitted to the object, which is obtained from the electrical image signal, with a predetermined value to evaluate the amount of light received; operating the light emission means when an evaluation result shows that the received light amount is insufficient; obtaining at least one of the main light emission amount and the gain from the amount of the light received when no light is emitted to the object and the amount of the light received during the preliminary light emission; setting at least one of the light emission amount obtained during the main light emission and the gain, as a set value, while maintaining the operation of the electronic camera below a camera shake limitation parameter thereof; and photographing the object with the main light emission amount set and the gain set.

Claim 20

An electronic camera comprising: a flash portion configured to provide a variable amount of light; an amplifying portion configured to variably set a sensitivity of a solid-state imaging element; a mode setting portion configured to be capable of setting a plurality of shooting modes; and a control portion configured to set an amount of light for a main light emission and a gain in the amplifying portion, based on the reflected light amount from an object and a shooting mode set by the mode setting portion, by making the flash portion perform a preliminary light emission in response to the start of a shooting sequence at a brightness below a camera shake limitation.

Claim 21

An electronic camera comprising: a flash portion configured to provide a variable amount of light; an amplifying portion configured to variably set a sensitivity of a solid-state imaging element; a mode setting portion configured to be capable of setting a plurality of shooting modes; and a control portion configured to set an amount of light for a main light emission and a gain in the amplifying portion, based on the reflected light amount from an object and a shooting mode set by the mode setting portion, by making the flash portion perform a preliminary light emission in response to the start of a shooting sequence at a brightness below a camera shake limitation.

Claim 22

The electronic camera according to claim 16 , wherein the mode setting portion includes in said plurality of shooting modes an automatic mode, a fixed gain mode and a power-saving mode.

Claim 23

The electronic camera according to claim 16 , wherein the control portion issues an alarm when changing the gain in the amplifying portion.