Photography – Flash system responsive to focal length or distance
Reexamination Certificate
1999-08-30
2001-02-06
Perkey, W. B. (Department: 2851)
Photography
Flash system responsive to focal length or distance
C396S159000
Reexamination Certificate
active
06185374
ABSTRACT:
This application is based upon application Nos. 10-247285 and 10-247305 filed in Japan, the contents of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention generally relates to a camera, and particularly relates to a mechanism for controlling a flash light emission of the camera. The present invention also relates to a method for controlling the flash light emission.
2. Description of the Related Arts
Conventionally, there have been proposed a variety of cameras each of which is able to photograph a subject (i.e. an object to be photographed) while emitting a flash light from a flash gun of the camera under a condition in which there is set a predetermined contribution rate for each of a plurality of light adjustment fields (or regions) that are formed by dividing a photographing field (or region). According to such a camera, a light adjustment control (or a control of the emission of the flash light) is performed as follows.
That is, as shown in
FIG. 3
for example, an OUTPUT DEVICE FOR INFORMATION UPON SUBJECT S
2
detects a location of a main subject to be photographed, a distance up to the main subject, a state of the background, and so forth, on the basis of a photometric value which is optically measured by a MULTI-DIVISION PHOTOMETRIC DEVICE S
6
, and on the basis of a focusing value which is measured by a FOCUSING DEVICE S
7
, in order to execute the light adjustment control. A CALCULATOR FOR CALCULATING CONTRIBUTION RATE OF LIGHT ADJUSTMENT S
3
calculates a contribution rate of light adjustment, for example, on the basis of information upon the main subject detected by the OUPTPUT DEVICE FOR INFORMATION UPON SUBJECT S
2
, and on the basis of a photometric value which is optically measured by preparatorily making the flash gun emit the flash light by a PREPARATORY LIGHT EMISSION MONITOR S
8
. A LIGHT ADJUSTMENT CONTROL DEVICE S
4
controls a MULTI-DIVISION LIGHT ADJUSTMENT DEVICE S
5
on the basis of the contribution rate of light adjustment which is calculated by the CALCULATOR FOR CALCULATING CONTRIBUTION RATE OF LIGHT ADJUSTMENT S
3
, so that the contribution rate is set for each light adjustment region or field.
According to the mechanism, the light adjustment control is executed by calculating the contribution rate of light adjustment in accordance with a specified algorithm on the basis of the results of photometry (or photometric measuring), focusing operation and preparatory light emission.
However, in order to improve the performance, or ability, of the flash exposure, there is need of increasing the number of light measuring points and/or increasing the number of focusing points and/or complicating the algorithm, so that the time of calculation or operation required for the light adjustment algorithm, and/or the time of control required for the light adjustment, become(s) longer.
On the other hand, conventionally, there have been proposed a variety of cameras in each of which it is possible to take a photograph while making a flash light emit from a flash gun with a state in which the amount of flash light is controlled in accordance with a photographing condition. Such a camera has a construction as follows.
That is, as shown in
FIG. 39
for example, an OUTPUT DEVICE FOR INFORMATION UPON SUBJECT POSITION S
25
of the camera detects a location of a main subject to be photographed, a distance up to the main subject, a state of the background, and so forth, on the basis of a photometric value which is optically measured by a MULTI-DIVISION PHOTOMETRIC DEVICE S
6
, and on the basis of a focusing value which is measured by a FOCUSING DEVICE S
7
. A CALCULATOR FOR CALCULATING COMPENSATION VALUE OF LIGHT ADJUSTMENT S
30
detects a compensation value for light adjustment, on the basis of information, detected by the OUTPUT DEVICE FOR INFORMATION UPON SUBJECT POSITION S
25
, upon the subject to be photographed. A LIGHT ADJUSTMENT CONTROL DEVICE S
4
controls an amount of flash light emission, on the basis of the compensation value for light adjustment which is calculated by the CALCULATOR FOR CALCULATING COMPENSATION VALUE OF LIGHT ADJUSTMENT S
30
.
According to the mechanism, the light adjustment control is executed by calculating the compensation value for light adjustment in accordance with a specified algorithm on the basis of the results of photometry (or photometric measuring) and focusing operation.
However, in order to improve the performance, or ability, of the flash exposure, there is need of increasing the number of light measuring points and/or increasing the number of focusing points and/or making preparatorily the flash light emit from the flash gun, so that the algorithm becomes complicated. Namely, accompanying the complication of the algorithm, the time of calculation or operation required for the light adjustment algorithm, and/or the time of control required for the light adjustment, become(s) longer.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a camera with a mechanism for controlling a flash light emission in which it is possible to control a light adjustment with a high accuracy in a short time.
It is another object of the present invention to provide a method for controlling the light adjustment.
In order to achieve the above object, according to one aspect of the present invention, there is provided a camera, comprising: an image sensor for sensing, or detecting, an image of a subject to be photographed, and for outputting subject information by processing data of the image; a plurality of light adjustment sensors for receiving a light which reflects from the subject, wherein each of the light adjustment sensors has a light receiving region which corresponds to at least a part of the light, and wherein the light adjustment sensors receive the light when a flash light is emitted; a calculator for calculating a contribution rate of an output supplied from each of the light adjustment sensors, on a basis of the subject information output from the image sensor; and a controller for controlling an emission of the flash light, on a basis of the contribution rate calculated by the calculator.
In the mechanism, the flash light may be emitted by a flash gun, for example, of the camera.
According to the mechanism, it is possible to accurately detect a condition of the subject to be photographed, such as a location, or position, of a main subject, and a relative positional relation between the main subject and its background, on the basis of the data of the image which is processed in the image sensor. Therefore, it is possible to enhance a performance, or ability, to control the flash light emission by accurately calculating the contribution rate relative to the light receiving region of each light adjustment sensor, and/or it is possible to shorten the time which is required to control the light adjustment, for example, by omitting a control of a preliminary flash light emission.
Consequently, according to the mechanism, it is possible to control the light adjustment with a high accuracy in a short time.
The one aspect of the present invention, for example, can be embodied as follows.
That is, as shown in
FIG. 1
, the image sensor may comprise an IMAGE TAKING DEVICE S
1
and an OUTPUT DEVICE FOR INFORMATION UPON SUBJECT S
2
. In this arrangement, for example, the IMAGE TAKING DEVICE S
1
takes in, or senses, an image of the subject to be photographed and outputs the data of the image (for example, image information upon the subject to be photographed, contour detection information, vector detecting information, color information, etc) to the OUTPUT DEVICE FOR INFORMATION UPON SUBJECT S
2
. The OUTPUT DEVICE FOR INFORMATION UPON SUBJECT S
2
outputs subject information on the basis of the data of the image output from the IMAGE TAKING DEVICE S
1
. The subject information is information upon the condition, or state, of the subject to be photographed, and the subject information includes, for example, information upon: a main subject regi
Fujino Akihiko
Kawabe Koutaro
Seki Reiji
Yamaguchi Motoshi
Minolta Co. , Ltd.
Perkey W. B.
Sidley & Austin
LandOfFree
Mechanism for controlling flash light emission, camera with... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Mechanism for controlling flash light emission, camera with..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mechanism for controlling flash light emission, camera with... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2611419