JPH04364671A - Image pickup device - Google Patents

Abstract

PURPOSE:To attain image pickup by proper exposure by utilizing a lighting means used in the moving picture mode without use of an external strobo device or the like even when an object brightness is low when the image pickup device able to select the still picture mode and the moving picture mode is used in the still picture mode. CONSTITUTION:A main CPU 9 reads the state of a mode switch 10 selecting either the still picture mode or the moving picture mode and the above CPU 9 discriminates it that the brightness of an object is lower than a prescribed brightness based on the still picture mode and the photometry information of the CCD 2. The CPU 9 sends a light-on signal to a battery light 12 to light up the above light for a prescribed time thereby implementing image pickup the same as the case with using a strobo.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an imaging apparatus, and more particularly to an improvement in a battery light control sequence in an imaging apparatus capable of switching between a still image mode and a moving image mode.

0002

2. Description of the Related Art As is well known, when photographing a low-luminance subject, it is common to photograph the subject while illuminating the subject with auxiliary light. When taking images in video mode with an imaging device that can switch between video mode and still image mode, such as a camera-type VTR, it is necessary to continue shooting for a certain period of time, so power is supplied from the battery. Lighting means such as battery lights used are always provided.

0003

However, when trying to take a picture in still image mode using such an imaging device, such as an 8 mm video camera, if the brightness of the subject is low, it becomes impossible to take a picture. So if you try to avoid this,
For example, it was necessary to provide a separate external strobe device or the like.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to solve the above-mentioned problems, and to solve the above problem, when shooting in still image mode using an imaging device that can switch between still image mode and moving image mode, even if the brightness of the subject is low, it is possible to use an external strobe device, etc. An object of the present invention is to provide an imaging device capable of capturing an image with proper exposure by using an illumination means used in a moving image mode without using a video mode.

[0005]

[Means for Solving the Problems] An imaging device of the present invention is capable of switching between a still image mode and a moving image mode, and has an illumination means for illuminating a subject under predetermined conditions in the moving image mode. a photometric means for measuring the brightness of the subject; a determining means for determining whether the subject is in a still image mode or a moving image mode; and a light emission control means for operating the illumination means and performing predetermined light emission control.

[0006]

[Operation] In this imaging device, when the determination means determines that the still image mode is selected, and the photometry means determines that the brightness of the subject is less than a predetermined brightness, the illumination means is operated to perform predetermined light emission control.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings.

FIG. 1 is a block diagram of an imaging apparatus showing a first embodiment of the present invention.
The subject light that has passed through a is sent to the SSG (synchronization signal generator) 7
The image is formed on the light-receiving surface of the CCD 2, which is driven and controlled by a synchronizing signal from the CCD 2. The video signal photoelectrically converted by the CCD2 is
After the processing circuit 3 performs necessary signal processing including white balance setting, the signal is supplied to the memory 4 and stored. Furthermore, the output signal of the memory 4 is magnetically recorded by a tape recording system 5.

The above iris control circuit 6, SSG
7 and the process circuit 3 include a camera control CPU as a discriminator that controls camera operation in cooperation with the main CPU 9 that controls the operation sequence of the entire imaging device.
A control signal is supplied from 8. As a result, this camera control CPU 8
D control, iris control, photometric information processing, various calculations,
Control a series of other necessary camera operations. Note that the photometry operation in this first embodiment is performed by processing electrical signals photoelectrically converted by the CCD 2,
This controls the shutter speed when the CCD 2 is used as an element shutter. In other words, C.C.
D2 also serves as photometry means.

Switch inputs are supplied to the main CPU 9 from a mode switch 10 for switching between a moving image mode and a still image mode, and a trigger switch 11 that replaces a shutter in the still image mode. Further, the main CPU 9 is also supplied with subject brightness information that has been arithmetic-processed by the camera control CPU 8. Therefore, the same CPU9
When the CPU 9 determines that the subject brightness is less than a predetermined value and that it is a still image mode, the CPU 9 communicates with the battery light 12 serving as the illumination means and transmits a lighting command to the light 12. In other words, the CPU 9 serves both as the determination means and the light emission control means in the claims.

FIG. 2 is a timing chart of the operation of each part in FIG. 1, in which the operation of each part is performed in synchronization with the vertical synchronization signal Vsync. That is, when this imaging device is set to still image mode and the shutter release button is pressed at time t1, the light-on signal 20 is sent from the CPU 9 shown in FIG.
is supplied to the battery light 12, thereby causing the battery light 12 to light up. Therefore, the light quantity 21 reaches the maximum luminous quantity within one field period, that is, within 1/60 second in the case of the NTSC system, and maintains this maximum luminous quantity for several subsequent fields.

After that, photometry operation 22 using the output of the CCD 2
is repeatedly executed for several fields, and based on the photometry results, an exposure operation 23 and a shutter operation 24 are executed. When this shutter operation ends, the light-on signal 20 from the main CPU 9 disappears, so the light amount 21
gradually decreases to zero. At the same time, the imaging information is shown in Figure 1 above.
After processing in the process circuit 3, a memory operation 25 to the memory 4 is performed. Furthermore, a recording operation 26 is performed on a recording medium such as a magnetic tape in the next field. Note that in the continuous shooting mode, it is also possible to extend the on time of the battery light 12.

The mode setting operation of the first embodiment configured as described above will be explained with reference to the flowchart shown in FIG. When this flow starts, it is checked whether the mode switch 10 (see FIG. 1) is set to the still image mode side (step S1). If the mode switch 10 is not set to still image mode, the process advances to step S2 and is set to moving image mode. On the other hand, if the still image mode is set, the process proceeds to step S3, where photometry is performed, and based on this photometry information, the main CPU 9 determines whether or not it is necessary to turn on the battery light 12 (step S4).

If it is determined that there is no need to turn on the battery light 12, photographing in the normal still image mode is executed without turning on the battery light 12 (step S5). On the other hand, as a result of the main CPU 9 determining the photometric information in step S3 above, if it is determined that it is necessary to turn on the battery light 12, the white balance is set to tungsten, which means that the color temperature is approximately 340.
After setting the temperature to 0°K (step S6), shooting in the still image mode is executed while irradiating the battery light 12.

The above is a flow related to the control of the battery light in the still image mode, but the control of the light in the movie mode will now be briefly explained. Normally, when it is determined that the mode is not still image mode, that is, it is video mode, normal light metering is performed, and if it is determined that a light is necessary based on the result of this light metering calculation, a light lighting signal is automatically sent to the main CPU.
9 to the battery light 12, the same light 12
I'm trying to make it light up.

FIG. 4 is a block configuration diagram of an imaging device showing a second embodiment of the present invention. This second embodiment is largely different from the first embodiment described above.
Instead, a dedicated photometric element 13, a photometric calculation circuit 14, and a reflecting plate 15 having a semi-transparent part in the center are used.Other than this, there is no difference from the first embodiment described above. , the same constituent members are given the same reference numerals and their explanations will be omitted.

FIG. 5 is a timing chart of operation waveforms of each part in FIG. 4. When the still image mode is selected by the mode switch 10 at time t11, mode setting 31 is performed. Next, when the trigger switch 11 shown in FIG. 4 is pressed down, each part operates in synchronization with the vertical synchronization signal, Vsync, in the same way as in FIG. 2 in the first embodiment. In this case, there is no difference from the first embodiment except that only photometry is performed by an external photometry element 13 instead of the CCD 2, so the same operations will be given the same reference numerals and their explanation will be omitted.

The flow of the mode setting operation in this second embodiment is the same as that shown in FIG. 3 above.

According to each of the above embodiments, in an imaging device capable of switching between a still image mode and a moving image mode, the battery light is also used as a strobe, thereby eliminating the need for a strobe and its drive circuit, etc. It is now possible to shoot in either video mode or still image mode even in bright light.

[0020]

As described above, according to the present invention, when the determining means determines that the still image mode is selected, and the photometric means determines that the brightness of the subject is below a predetermined brightness,
In video mode, the lighting means that illuminates the subject is operated under predetermined conditions, and the light emission control means performs predetermined light emission control, so that an imaging device that can switch between still image mode and video mode can be used in still image mode. When shooting with
Even if the subject is dark, it is possible to take pictures with proper exposure using the illumination means used in the moving image mode without using an external strobe device or the like.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram of an imaging device showing a first embodiment of the present invention.

FIG. 2 is a timing chart of the operation of each part in FIG. 1;

FIG. 3 is a timing chart of mode setting operation in the first embodiment.

FIG. 4 is a block configuration diagram of an imaging device showing a second embodiment of the present invention.

FIG. 5 is a timing chart of the operation of each part in FIG. 4;

[Explanation of symbols]

2...CCD (photometering means) 8...Camera control CPU (discrimination means) 9...Main CPU (discrimination means, light emission control means) 12...Battery light (illumination means) 13...External photometry element (photometering means)

Claims (1)

[Claims] Claim 1. An imaging device capable of switching between a still image mode and a moving image mode, and having an illumination means for illuminating a subject under predetermined conditions in the moving image mode, comprising: a photometry means for measuring the brightness of the subject; mode or video mode, and if the determining means is the still image mode, the light metering means operates the lighting means to control the light emission in a predetermined manner when the light metering means respectively determines that the brightness of the subject is below a predetermined brightness. An imaging device comprising: a light emission control means for performing the following steps.