KR100401172B1 - Intensity of Illumination Dynamic Range Photographing Device for CCD - Google Patents

Abstract

The present invention relates to illuminance broadband imaging means for charge-coupled devices (CCD) usable for video cameras, digital cameras, surveillance cameras and the like.

According to the present invention, when a subject including a simple light source such as the sun or a light having extremely high illumination or a partial partial illumination difference of the subject is large, the illumination of the high illumination portion is lowered to or below a set value so that the entire subject can be photographed. .

To this end, the present invention controls the LCD driving circuit by comparing the signal output of the DSP connected to the CCD with the reference signal to adjust the image illuminance of the subject reaching the CCD, so that all subjects are properly illumined despite the severe deviation of the illuminance of the subject. To be photographed.

Accordingly, the present invention has an effect of contributing to the diversification and enhancement of the function of the photographing apparatus by allowing the entire photograph of the subject to be normally photographed even when a simple light source exists in the subject or when the partial illuminance difference of the subject is severe.

Description

Intensity of Illumination Dynamic Range Photographing Device for CCD

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to illuminance broadband imaging means, and more particularly to illuminance broadband imaging means for use in video cameras, digital cameras, surveillance cameras, and the like (hereinafter referred to as " charge-coupled device "

As is well known, video cameras, digital cameras, surveillance cameras, and other imaging apparatuses have a structure in which lenses, apertures, and CCDs are arranged in sequence, and light emitted from a subject is refracted through the lens and thus the amount of light transmitted by the aperture is stopped. After the control, it is designed to be imaged on the CCD.

The conventional photographing means controls the aperture so as to lower the overall illuminance in order to enable the whole photographing when a part of the subject, such as sunlight or a lighting, has a high illuminance or a partial deviation in the illuminance of the subject is severe. It is a problem that the relatively low-light portion is taken darker and the overall shooting of the subject is impossible.

To solve this problem, an object of the present invention is to set a light that reaches a corresponding pixel of a CCD corresponding to a high light intensity when a large amount of light is incident on a part of a subject or when a partial light intensity deviation of a subject is severe. The present invention provides an illuminance wideband photographing means capable of widening the illuminance range of a photographable subject by attenuating below.

1 is an explanatory diagram showing a general CCD photographing means.

2 is an explanatory diagram showing a CCD photographing means according to the present invention;

3 is a schematic view showing the configuration of the photographing means according to the present invention;

4 is an explanatory view showing the operation of the photographing means according to the present invention;

5A, 5B, and 5C are explanatory diagrams showing an example of a high-illuminance subject.

* Explanation of symbols for the main parts of the drawings

1: lens system

2: aperture

3: CCD

4: control output

5: Video signal generator

6: Video signal output section

7: output

8: DSP

9: microprocessor

10: LCD driving circuit

11: LCD

An object of the present invention is to provide a known imaging means that the light of the subject reaches the CCD through the lens aperture, the LCD between the lens and the CCD, the signal output of the DSP (digital signal processor) connected to the CCD The present invention proposes a roughness broadband photographing means for CCD, which is capable of controlling an LCD driving circuit against a reference signal.

Accordingly, in the present invention, when the partial illuminance of the subject such as sunlight or a lighting is excessively high or when the partial illuminance deviation of the subject is severe, the LCD captures only a specific portion of the image reaching the CCD to a set value, thereby enabling normal photography. The present invention will be described in more detail with reference to the accompanying drawings so that the imageable illuminance range is widened as follows.

As shown in FIG. 2, the present invention provides a lens system 1 composed of a plurality of lenses;

Aperture 2 for adjusting the amount of light passing through the lens system 1, CCD 3 that the image of the subject reaches, CCD pixel 3 for the operation of the CCD clock and trigger signal lamp 3 In the known imaging means composed of a control output section 4 and a video signal output section 6 composed of a video signal generator 5 or the like for generating a video signal at the output of the CCD 3, the CCD 3 In order to acquire the output signal for each pixel of), the CCD control output unit 4 and the pixel output unit 7 are connected to amplify the analog signal output and convert the signal output into a digital output signal and compare it with the reference signal. DSP 8 outputting the pixel address data when the value is greater than the set value, a microprocessor 9 for converting the data output of the DSP 8 into a control output for driving the LCD 11, and a microprocessor 9 An LCD driving circuit 10 for driving the LCD 11 by Will the yeoseo.

In the present invention as described above, light from the subject passes through the lens system 1 and the aperture 2, which are usually composed of three or more sheets, to form an image on the CCD 3.

At this time, when light in the normal illuminance range is incident on the CCD 3, the voltage value corresponding to the image is output from the output unit 7 of the pixel by the output of the CCD control output unit 4 applied to the CCD 3. This output value is stored in a memory, and is converted into an image signal by the image signal generator 5 and outputted to be used in a form suitable for each purpose such as a video camera, a digital camera, a surveillance camera, and the like.

At this time, in the present invention, the CCD control output section 4 and the output generated from the pixel output section 7 of the CCD 3 are applied to the DSP 8. Accordingly, the DSP 8 amplifies the output provided by the pixel output unit 7 to a size suitable for data processing, converts the analog signal into a digital value, and contrasts the digital value with a set value. As a result, in the normal case in which the subject image in the normal illuminance range is incident, the digital value is not larger than the set value so that no output is generated. Accordingly, the microprocessor 9 does not generate the control output of the LCD driving circuit 10, and therefore the LCD 11 maintains a transparent state to enable normal photography.

In such a state, when a simple light source such as the sun or a light is used to capture an image included in a subject or when the partial illuminance difference of the subject is severe, ordinary means of photographing using the CCD (3) may stop the aperture in order to enable overall shooting. It works by reducing the overall illumination, such as by reducing, so that the other main parts of the subject dark together, the problem is that shooting is impossible. In the present invention, in particular, when the illuminance of a part of the subject is high or the illuminance variation for each part of the subject is extreme, the output value of the specific pixel output unit 7 of the CCD 3 is increased, which is converted into digital by the DSP 8. It is determined that the value is greater than or equal to the specified value, and the DSP 8 outputs data corresponding to the address of the pixel. Accordingly, the microprocessor 9 immediately converts the output value of the DSP 8 to control the specific position of the LCD 11 and drives the LCD 11 to display a specific portion A of the CCD 3 as shown in FIG. Illuminance of light passing through a specific portion of the LCD 11 is attenuated by causing the color to develop in a specific portion A 'of the LCD 11 corresponding to). Will be done.

To this end, the driving of the specific portion A 'of the LCD 11 may be controlled in pixel units or may be controlled in shade units, which are unit areas, not pixel units.

In the present invention, it is a matter of course that the LCD 11 can obtain a natural video signal by making the brightness level of the color appearing transparent and black and gray in the middle thereof optimally according to the setting of the visual level.

Accordingly, in the present invention, as shown in FIG. 4, when the illuminance of the specific portion A of the subject is very high, or when the illuminance difference between the specific portion A and the other portion of the subject is severe as shown in FIGS. 5A, 5B and 5C. In this case, the illuminance of the specific portion is reduced, so that the entire main portion of the subject can be photographed by the CCD 3, so that normal photographing can be performed even in a subject having a large illuminance difference.

In the present invention, if the illuminance of a particular part of the subject is very high, lowering the illuminance of only that part may cause an unbalance of overall contrast. By controlling the LCD driving circuit 10 by the DSP (8) so as to lower the overall illuminance, it is possible to obtain a natural image.

In addition, in the present invention, such a series of operations must be implemented in real time, and therefore, a DSP 8 and a microprocessor 9 with improved data processing speeds should be used.

In addition, in the present invention, the illumination limit value set by the DSP 8 and the illumination intensity can be lowered step by step than the normal illuminance portion around the specific portion A having a very high illuminance. Of course, you can also use the keypad 12 to select the.

In this way, the present invention allows the entire subject to be photographed even when the subject includes extremely high illuminance, such as in the case of a light source such as the sun or light, or when the illuminance of the subject shows a large difference. It is possible to extend the illuminance range of a high-capacity subject to a very wide range, and to capture various kinds of subjects, and to diversify and enhance the functions of a video camera, a digital camera, and a surveillance camera. When applied to, it has the effect of having excellent performance that can be monitored in any illuminance situation.

Claims (3)

A lens system 1 composed of a plurality of lenses, an aperture 2 for adjusting the amount of light passing through the lens system 1, a CCD 3 at which an image of a subject arrives, and a pixel clock of the CCD 3 And an image signal output unit 6 composed of a control output unit 4 for operating the CCD 3 of the trigger signal lamp and an image signal generator 5 for generating an image signal at the output of the CCD 3. In the known imaging means configured In order to acquire an output signal for each pixel of the CCD 3, the CCD control output unit 4 and the pixel output unit 7 are connected to each other. A digital signal processor (DSP) 8, a microprocessor 9 for converting the data output of the DSP 8 into a control output for driving the LCD 11, and an LCD driven by the microprocessor 9; (11) and its LCD drive circuit (10), characterized in that the CD broadband imaging means for the CD. The method of claim 1, A roughness broadband photographing means for a CD, characterized in that the LCD (11) driven by the microprocessor (9) is controlled in units of pixels. The method of claim 1, A roughness broadband photographing means for a CD, characterized in that the LCD 11 driven by the microprocessor 9 is controlled in shade units.