JPH04117876A - Picture input device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an image input device, and more particularly to an image input device that ensures more reliable image recording when taking pictures using a flashlight. .

[Conventional technology]

Conventionally, when capturing an image, flash illumination using a flashlight emitting device is used as necessary. Keep the amount of light emitted constant and control the aperture to an appropriate value for the distance.

2) Controlling the amount of light emitted by the flashlight emitter using the sensitivity, aperture F number, and subject distance as parameters.

Some methods have been adopted.

[Invention or problem to be solved]

From a non-directional light bulb that emits a luminous flux of L within a unit time,
When the light is projected onto a subject at a distance of 1fIld, the luminous intensity of the light source as seen from this subject is L/4π per unit solid angle, and if the reflection coefficient is M, the luminous intensity is LM/4π.
becomes. Then, the illuminance E of the subject is LM (1) E=4aD.

In addition, the flashlight emitter has an indicator that indicates that the kite nano<-G(,
F... (2) Then, using the kite number, the relationship among the imaging distance, sensitivity S, aperture F number, exposure time, etc. is determined.

For example, the amount of light emitted by a flashlight is constant, and using equipment with sensitivity S, the imaging method shown in Figure 4 is used to control the appropriate aperture F for the object O located at a distance. In this case, when the distance to the subject is too large and the amount of light emitted from the flash is outside the possible range of aperture value control, there may be cases where there is insufficient incident light for imaging even if the aperture is opened to the maximum. Controllable distance range. For example, if the subject device is at a distance twice that of Do, the subject illuminance will be 1/4 of that of DO, according to equation (1) above, and appropriate imaging will either be abandoned or the kite number will be more closely spaced. This required a large flashlight, that is, a flashlight with a large amount of light emitted.

This invention was made to solve the above-mentioned problems of the prior art, and it is possible to image a subject at a distance where the amount of light from the flash device is insufficient, to a certain extent, without replacing the flash device. [1] The first objective is to provide an image input device that can be used as an image input device.

[Means to solve the problem]

For this reason, the image input device according to the present invention includes an imaging section that converts an optical image of a subject into electrical signals of a plurality of pixels and outputs the electrical signals;
When taking an image using a flashlight emitter, if the amount of light obtained by the flashlight emitter is insufficient, an adding means for adding up the electrical signals of a plurality of pixels output from the imaging section is provided, and according to the degree of the shortage of light, an addition means is provided. The above object is achieved by a configuration characterized in that the addition state is changed by changing the addition state.

(Function) With the above configuration, the optical image of the subject is converted into electrical signals of a plurality of pixels in the imaging section and output, and image information is formed from the electrical signals of the plurality of pixels.

When taking an image using a flashlight emitter, if the amount of light obtained by the flashlight emitter is insufficient, the adding means adds up the electrical signals of the plurality of pixels output from the imaging unit, and also determines the degree of the shortage of light amount. By changing the addition state according to the amount of light, it becomes possible to take an image with an apparent increase in the amount of light.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An image input device for mother and child according to the present invention will be described by way of an embodiment.

FIG. 1 is a block diagram showing one embodiment of the present invention. The light beam from the subject θ passes through the imaging lens 1, the diaphragm section 2, and the optical low-pass filter 3 that form the optical system a, and is input to the solid-state image sensor 4 of the imaging section. In addition, the aperture part 2
is driven by a drive circuit 9 controlled by a control signal from a system controller 8 to control the aperture value.

The charges accumulated in the solid-state image sensor 4 are driven by a drive circuit 10 controlled by a control signal from a system controller 8, read out as electrical signals of a plurality of pixels, amplified by an amplifier circuit 5, and output from the image sensor. . Then, it is input to the A/D conversion circuit 6 and converted into a digital signal, and the signal processing circuit 7 performs the necessary processing to convert it into a recorded Buddhist name, and output it as image information.Then, it is compressed by the compression unit 12. The image data is recorded in the image memory of the image data recording section 3.

Note that the solid-state image sensor 4. The drive circuit 10 and the system controller 8 also constitute an adding means that adds and outputs electrical signals of a plurality of pixels.

The flash light emitting circuit 11 performs flash light emitting imaging when the illuminance of the subject measured by the photometer 17 is less than a predetermined illuminance as a result of photometry. When a flash is required, the system controller roller 8 sends a control signal to the flash light emitting circuit 11, and the flash light emitting circuit 1
The main capacitor No. 1 is charged, and when the charging is completed, a signal is sent to the system controller 8 indicating that charging is complete, and the charge on the main capacitor is reduced by sending an l rigger pulse to the flash light emitting circuit 11 in conjunction with the subsequent suppression of the release switch 5W16. Discharge and emit light.

Next, the features of this invention will be explained.

The image input device of this embodiment has, in addition to a moat 1 that operates with normal imaging pixel sensitivity, a moat 2 that increases the apparent pixel sensitivity by adding an electric charge converted by an adjacent pixel by an adding means. and (-3).

FIG. 2 is an explanatory diagram of the imaging mode. In Moto 1, a plurality of pixels 411, . 1-12.
4-13. ...4-21,422, ...
The drive circuit 10 has each pixel as an independent pixel.
The structure is such that the unit driven optical image is read out as an electrical signal.

In mote 2, pixels 4-11 and 4 are added by the addition means.
-12. Pixels 4-21 and 4-22. . . . Two adjacent pixels are added together to form a unit optical image electrical signal.

In mode 3, pixels 411 and 4 are added by the addition means.
Adjacent four pixels such as -1.2.4-21.4-22 are added to form a JP-composition optical image electrical signal and output. Therefore, in Mo1'3, it is possible to obtain a unit-constituent optical image electrical signal having four times as much charge.

In the above-mentioned FIG. 4, the object θ at a distance is
The aperture value F of the diaphragm section 2 is controlled in accordance with the amount of light from the diaphragm and the sensitivity of the imaging section. If the predetermined amount of light is not q4I by the aperture control described above, it is determined that it is "dark" and a flash is required to be emitted, so the system controller 8 sends a flash light emission control signal to the flash light emission circuit 11 and moves to a flash light emission imaging operation. .

Here, the operation when the subject θ is at such a distance that the aperture unit 2 is opened to the maximum and the amount of light from the subject b is insufficient during flash emission will be described with reference to the flowchart shown in FIG.

First, in step S1, the distance mtD to the subject is measured by automatic focusing (AF) operation. In step S2, the maximum subject distance D0 that can satisfy the subject illuminance based on the flash kite number is compared with the subject distance measured in step S1. If D<Do, that is, if appropriate imaging is possible with aperture control using a regular guide number, step S3
Proceed to step 2 and set the imaging mode 1<'1. Then, in step S4, release switch SW1.
6 is turned on, the process proceeds to step S5, where the strobe light is emitted, and at step S6, an optical image signal is output from the solid-state image sensor 4, and writing to the image data recording section 13 is executed, and the operation ends.

Also, if the subject distance in step S2 is the maximum subject distance. If it is determined that the above is the case, the process proceeds to step S7, and if the flash image is captured, the process proceeds to step s8. And the distance to the subject is increasing. 111, 4D.

It is determined whether the condition is within the range, and if this condition is satisfied, step S9
Go to step S10 and add up the 2×1 pixel range shown in mode 2 in FIG. The operations of steps S4 to S6 are performed, respectively, and the process ends.

With the above operation, even under conditions where the amount of light emitted by the flashlight is insufficient in normal imaging, the resolution can be reduced by automatically switching from mode 1 to mode 2 or mode 3. Alternatively, it is possible to perform imaging that compensates for the lack of light from the flashlight emitter.

In addition, Mort 2. m-position constituent light image '1' in moat 3
E Kii 8. In the embodiment, the number is set to be 2 (F ~, 4 times) for 11, but the number is not limited to the multiple of the embodiment, and the number may be set to any desired number. good.

〔Effect of the invention〕

As explained above, according to the present invention, an optical system forms an optical image of a subject, an imaging unit converts the optical image into an electrical signal of a plurality of pixels and outputs it, and image information is obtained from the electrical signal of the plurality of pixels. form.

When taking an image using a flashlight emitter, if the amount of light obtained by the flashlight emitter is insufficient, the imaging unit transfers the unit constituent optical image electrical signals constituting the output electrical signals of multiple pixels to adjacent pixels. It is constructed by adding the charges converted by
By strengthening the electrical signal output of the unit constituent optical image and changing the addition state according to the degree of insufficient light quantity, it is possible to increase the light quantity of the viewing area and capture images.

In other words, it is possible to provide an image input device that can increase the distance to the subject without using a flashlight that emits a larger amount of light.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram of the imaging mode of the embodiment, FIG. 3 is an operation flowchart of the embodiment, and FIG. 4 is an illustration of imaging. a...Optical system b...Imaging section 1...Imaging lens 2...Aperture section 3...Optical low-pass filter 4... ... Solid-state image sensor 5 ... Amplifier circuit 6 ... A/D conversion circuit 7 ... Signal processing circuit 8 ... System controller 9 ... ... Aperture control circuit 10 ... Solid-state image sensor drive circuit 11 ...
・Flash (units)・) Light emitting circuit 12... Compression circuit 13... Both image data recording section 14... AF sensor 5... AF drive circuit 6 ...Release switch 7 ...Photometering section

Claims (1)

[Claims] An imaging unit that converts an optical image of a subject into electrical signals of multiple pixels and outputs the same; and a plurality of pixels that the imaging unit outputs when the amount of light obtained by the flash unit is insufficient when capturing an image using a flash unit. An image input device comprising: an adding means for adding electric signals of pixels; and an adding state is changed according to the degree of the light quantity shortage.