KR101592407B1 - Picture quality enhancement apparatus, digital photographing apparatus with the same and picture quality enhancement method thereof - Google Patents

Abstract

The present invention relates to a ZRF (Liquid Crystal Display) having an LCD (Liquid Crystal Display) provided between a lens unit and an image sensor and transmitting light passing through the lens unit to irradiate the image sensor, Zone collected Reduction Filter); An image processor for processing the image obtained by the image sensor as data; And a ZRF controller for calculating the brightness of a plurality of regions partitioned in the image from the data processed by the image processor and controlling a light transmittance of the LCD region to reduce a brightness difference between regions in the image To a digital image pickup apparatus having the same, and to an image quality improving method.
According to the present invention, when there is an excessive brightness difference due to light saturation or light deficiency in each screen in a single screen, the light transmittance of each part is adjusted by ZRF (Zone Collected Reduction Filter) installed between the camera lens and the image sensor, And images with excellent color reproducibility are obtained.

Description

TECHNICAL FIELD The present invention relates to a picture quality enhancement apparatus, a digital photographing apparatus having the same, and a picture quality enhancement method,

The present invention relates to a picture quality improving apparatus, a digital photographing apparatus having the same, and a picture quality improving method. More particularly, the present invention relates to a picture quality enhancing apparatus and a picture quality improving method which have excellent sharpness and color reproducibility , A digital photographing apparatus having the same, and an image quality improving method.

Generally, a digital camera shoots an image on an image sensor, which is not a film but a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor), and records the image on a digital storage medium such as a memory card Record.

Such a digital camera is provided with an auto white balance (AWB) function on the whole screen when light is saturated due to excessive brightness of light from the image sensor or vice versa due to excessive light deficiency , And to improve it. At this time, there is a problem in the sharpness of the screen and the color reproducibility due to saturation or insufficient light per region.

In addition, when a difference occurs between the visible light region and the sensor sensitivity region, the digital camera operates to transmit a desired wavelength band using a color filter, because light other than the actual visible light region acts as noise in the entire area of one screen, The method of increasing the sharpness of the screen by adjusting the brightness of the light by adjusting the band appropriately, and taking a picture or recording a moving picture by distributing the color are used.

Techniques for improving image quality in conventional digital cameras include "CMOS image sensor having a color filter laminated as a light blocking layer" of Korean Utility Model Application No. 20-2001-0002331, Korean Patent Laid-Open No. 10-2007-0078463, Image sensor noise reduction apparatus and method "

However, these prior arts have a problem in that, when photographing with a digital camera, there is a limitation in securing the sharpness and color reproducibility of a photographed image when there is an excessive brightness difference due to lightening or light deficiency in a single screen.

According to an aspect of the present invention, there is provided a method of detecting a ZRF (Zone Collected Reduction Filter), which is installed between a lens unit and an image sensor, when an excessive brightness difference exists due to light saturation or light- ) To adjust the light transmittance of each part, thereby obtaining an image having excellent sharpness and color reproducibility. Other objects of the present invention will become readily apparent from the following description of the embodiments.

According to an aspect of the present invention, there is provided an image sensor comprising: a lens unit; an image sensor disposed between the lens unit and the image sensor; A ZRF (Zone Collected Reduction Filter) having an LCD (Liquid Crystal Display) whose light transmittance is adjusted for each of a plurality of regions partitioned by an active array and driven by a unit cell; An image processor for processing the image obtained by the image sensor as data; And a ZRF controller for calculating the brightness of a plurality of regions partitioned in the image from the data processed by the image processor and controlling a light transmittance of the LCD region to reduce a brightness difference between regions in the image An image quality improvement device is provided.

The ZRF may be installed between the image sensor and the IR cut filter provided between the lens unit and the image sensor so as to be offset toward the image sensor.

The ZRF has first and second polarizing plates attached to both sides of the LCD, each polarizing plate polarizing light in directions orthogonal to each other on the exposed surfaces of the respective glasses, and is disposed in a nomally white And the ZRF control unit controls the light transmittance of the area of the LCD to a minimum level when the difference in brightness among a plurality of areas partitioned in the image is within a normal range from the data processed by the image processing unit, The control of the transmittance can be prevented from being performed.

The LCD may have an area corresponding to a plurality of pixels as one unit in the image sensor.

The first and second polarizing plates may be formed in such a manner that the polarizing regions are uniformly or unevenly discontinuously formed in one direction, and the discrete arrangements of the polarizing regions are arranged in parallel.

The first and second polarizers may be wire grid polarizers.

The first and second polarizing plates are formed on the substrate of a light transmissive material such that a plurality of concavo-convex portions made of a light-transmitting dielectric material or polymer are patterned and arranged in a convexo-concave shape in one direction, A white metal may be deposited.

Wherein the ZRF control unit extracts a light defective area as an area deviating from a predetermined brightness difference in the area of the image and extracts a correction area as an area contributing to formation of the light defective area in the area of the image sensor An area through which the light to be irradiated to the correction area is transmitted as the control area among the areas of the LCD, and the light transmittance of the control area may be adjusted to be in inverse proportion to the brightness of the light defective area.

According to another aspect of the present invention, there is provided a lens unit comprising: a lens unit into which light is incident; An image sensor provided behind the lens unit; A main controller for controlling an image captured by the image sensor to be stored in a memory; And an image quality enhancement unit installed to control a light transmittance of the image sensor so as to reduce a brightness difference between regions in an image obtained by the image sensor, wherein the image quality improvement unit adjusts the quality of an image according to an aspect of the present invention A digital photographing apparatus is provided.

The digital photographing apparatus may be any one of a portable digital camera, a CCTV camera, a camera of a portable electronic device, a web camera, a camera module of a vision checker, and a camera module of a black box.

According to still another aspect of the present invention, there is provided a method of manufacturing an image sensor, comprising: obtaining an image from an image sensor irradiated with light through a lens unit and a zone collected reduction filter (ZRF); Processing the image as data; Calculating brightness of a plurality of regions partitioned in the image from the data; And controlling a light transmittance of a region of the ZRF divided into a plurality of regions so as to reduce a brightness difference between regions in the image.

Wherein the step of adjusting the light transmittance comprises the steps of extracting a light defective area as an area deviated from a predetermined brightness difference in the area of the image and correcting the light defective area as a region contributing to formation of the light defective area Extracting a region through which the light irradiated to the correction region is transmitted from the LCD region as a control region and controlling the light transmittance of the control region to be inversely proportional to the brightness of the light defective region.

According to the image quality improving apparatus, the digital photographing apparatus having the same, and the image quality improving method according to the present invention, when there is an excessive brightness difference due to light saturation or light deficiency in each area in one screen, By adjusting the light transmittance of each part by the zone collected reduction filter, it is possible to acquire an image having excellent sharpness and color reproducibility, and the resolution reduction effect of the digital photographing apparatus according to the screen brightness difference can be reduced.

1 is a configuration diagram showing a digital photographing apparatus according to an embodiment of the present invention.
2 is a cross-sectional view showing ZRF in a digital photographing apparatus according to an embodiment of the present invention.
FIG. 3 is a plan view showing a first light guide plate in a digital photographing apparatus according to an embodiment of the present invention. FIG.
4 is a plan view showing a second polarizing plate in the digital photographing apparatus according to an embodiment of the present invention.
5 is a plan view showing another example of the first light guide plate in the digital photographing apparatus according to one embodiment of the present invention.
FIG. 6 is a plan view showing another example of the second flat plate in the digital photographing apparatus according to one embodiment of the present invention. FIG.
7 is a cross-sectional view of Fig. 5 and Fig.
8 and 9 are conceptual diagrams for explaining the operation of the image quality improvement apparatus according to an embodiment of the present invention.
10 is a flowchart illustrating an image quality improvement method according to an embodiment of the present invention.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in detail in the drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but is to be understood to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention, And the scope of the present invention is not limited to the following examples.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant explanations thereof will be omitted.

1 is a configuration diagram showing a digital photographing apparatus according to an embodiment of the present invention.

1, a digital photographing apparatus 200 according to an exemplary embodiment of the present invention may include a lens unit 210, an image sensor 220, a main control unit 240, and an image quality improvement unit. , A CCTV camera, a camera of a portable electronic device, a web camera, a camera module of a vision checker, and a camera module of a black box, and may function as a camera according to the usage pattern Additional necessary configurations may be added, including a casing, a display portion, a control portion, a battery, and the like. Here, the portable digital camera may include a compact digital camera, a digital single lens reflex (DSLR) camera, a mirrorless camera, and various portable digital photographing devices.

The lens unit 210 serves to collect light to form an image on the image sensor 120, and may include a single lens or a plurality of lenses for this purpose.

The image sensor 220 is disposed behind the lens unit 210 and may be a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). An image focused on the chip surface is charged And these packets are output, converted into an image, and displayed. An IR cut filter 230 may be disposed in front of the image sensor 220 to be positioned behind the lens unit 210. The IR cut filter 230 is a filter that blocks infrared rays in order to improve the infrared cut filter 230 because the infrared cut filter 230 recognizes the infrared cut filter 230 as visible light as well as infrared light and reacts with the visible light.

The main control unit 240 controls the memory unit 250 to store the image captured by the image sensor 220 according to an operation signal from the operation unit or a predetermined process and outputs the image to the outside through a display unit .

The image quality improving unit is provided to control the light transmittance of the image sensor 220 so as to reduce the difference in brightness between regions in an image obtained by the image sensor 220. This is because the image quality improving apparatus 100). Therefore, the picture quality improving unit 100 will be described instead of the picture quality improving apparatus 100 according to an embodiment of the present invention.

The apparatus 100 for improving image quality according to an embodiment of the present invention may include a ZRF (Zone Collected Reduction Filter) 110, an image processing unit 120, and a ZRF control unit 130.

The ZRF 110 is installed between the lens unit 210 and the image sensor 220 and transmits the light that has passed through the lens unit 210 to the image sensor 220 so as to be illuminated, And an LCD (Liquid Crystal Display) 111 (shown in FIG. 2) in which the light transmittance is regulated for each of a plurality of regions partitioned by unit cell driving by placing an active array. The LCD 111 includes a plurality of pixels whose transmittance is controlled. Also, the active array may be a power supply circuit that is controlled by the ZRF control unit 130 and supplies power required for driving each unit cell formed of a single or a plurality of pixels. The size of the voltage, Thereby adjusting the application time. Accordingly, the LCD 111 can adjust the light transmittance of the pixel by the magnitude of the voltage applied by the ZRF control unit 130, the time of applying the voltage, and the like.

In the LCD 111, an area may be a unit in which the light transmittance is controlled by the ZRF controller 130, may be one or a plurality of pixels, and the ZRF controller 130 may set the area .

The ZRF 110 is shifted toward the image sensor 220 between the IR cut filter 230 and the image sensor 220 when the IR cut filter 230 is added between the lens unit 210 and the image sensor 220. [ Can be installed.

Referring to FIG. 2, the ZRF 110 may be provided with glass 112 and 113 on both sides of the LCD 111 as shown in the present embodiment. The ZRF 110 may be formed on the exposed surfaces of the glasses 112 and 113, The first and second polarizers 114 and 115 may be attached to the first polarizer 114 and the second polarizer 114, respectively. Also, each area on the LCD 111 can be configured to correspond to a plurality of pixels in the image sensor 220, which is only one example, and can be configured to correspond to a single pixel in the image sensor 220. [

As shown in Figs. 3 and 4, the first and second flat plate plates 114 and 115 may be polarized in the X axis direction and the Y axis direction, respectively, but not limited thereto. For example, And may have a polarization degree of 0.8 to 0.96, for example. The first and second polarizing plates 114 and 115 may be formed such that the polarizing regions 114a and 115a, that is, the regions for polarizing light, can be formed discontinuously uniformly in width and length in one direction, and the polarizing regions 114a and 115a, A plurality of discrete arrays may be formed in parallel. In addition, unlike the present embodiment, the first and second polarizers 114 and 115 may be formed such that the polarizing regions are formed unevenly in the width and the length in one direction, and the polarizing regions may be formed singly as a whole.

5 and 6, the first and second polarizers 116 and 117 may be formed of wire grid polarizers for polarizing light in mutually orthogonal directions, for example, glass or synthetic resin A plurality of irregularities 116a and 117a made of a light-transmitting dielectric or polymer can be formed on the substrates 116c and 117c made of a light transmitting material so as to be patterned in a unidirectional pattern in a unidirectional manner, White metals 116b and 117b such as silver or aluminum can be deposited in the same direction at the inner sides of the grooves of the grooves 116a and 117a. Patterning of the concave and convex portions 116a and 117a may be performed using a unit process for manufacturing semiconductors such as a photo process, an etching process, and the like. The rows of concavities and convexities formed by the grooves and the projections corresponding to the concave and convex portions 116a and 117a on the substrates 116c and 117c may be formed to correspond to the concave and convex portions 116a and 117a as in the present embodiment, And the protrusions 116a and 117a may be formed in parallel so as to be spaced apart from the protrusions 116a and 117a in the width direction.

The image processing unit 120 processes the image obtained by the image sensor 220 into data for calculating brightness for each of a plurality of divided areas and outputs the processed data to the ZRF controller 130.

The ZRF controller 130 calculates the brightness of a region partitioned into a plurality of regions in the image from the data processed by the image processor 120 and adjusts the light transmittance of the region of the LCD 111 to be smaller .

On the other hand, the ZRF 110 is configured to be nomally white, so that when the voltage is not applied, light can be transmitted to have the maximum luminance. In this case, the ZRF control unit 130 determines whether the brightness difference of a plurality of regions partitioned by an arbitrary setting in the image obtained by the image sensor 220 from the data processed by the image processing unit 120 is within a normal range, The control of the light transmittance to the area of the LCD 111 can be minimized or the light transmittance control can be prevented from being performed. Here, the minimum step may be a step of minimizing a change in light transmittance when the light transmittance of the LCD 111 is set to a plurality of steps. In this case, Can be performed on the area of the LCD 111 corresponding to the area.

The ZRF controller 130 extracts a light defective area as an area that deviates from a predetermined brightness difference in the area of the image acquired by the image sensor 220, for example, Extracts a correction region as a region contributing to the formation of the control region, extracts, as a control region, an area through which the light to be irradiated to the correction region is transmitted from among the regions of the LCD 111, and controls the light transmittance of the control region to be inversely proportional to the brightness of the light- . Here, the total brightness refers to the brightness of the entire image, which is determined by a grade or a numerical value. Also, the brightness of each region of the image is determined by grades or numerical values, and the brightness is averaged or a variety of methods . ≪ / RTI > In addition, the predetermined brightness difference may mean that the allowable range of brightness difference between some or all of the regions and any one of the regions is expressed as a grade or a numerical value.

Referring to FIG. 8, the ZRF control unit 130 determines that the image corresponding to the light saturation is a region that is excessively bright compared to the entire brightness due to a subject emitting strong light among regions of the image acquired by the image sensor 220, Extracts the defective area and extracts the correction area 222 as an area contributing to the formation of the light defective area in the areas 221 and 222 of the image sensor 220. In the area 111a and 111b of the LCD 111, It is possible to adjust the light transmittance of the control area 111b to be lowered at a predetermined ratio according to the brightness of the light defective area. At this time, the light-defective area, the correction area 222, and the control area 111b may be a single area or a plurality of areas among the areas partitioned by the setting in the corresponding object. In this embodiment, ) Is composed of four regions, and the control region 111b is one region.

Referring to FIG. 9, the ZRF controller 130 detects a darkness in an area of an image obtained by the image sensor 220, for example, due to a dark subject due to backlight, And extracts the correction area 222 as an area contributing to formation of the light defective area in the areas 221 and 222 of the image sensor 220 and extracts the correction area 222 out of the areas 111a and 111b of the LCD 111 222 is extracted as the control region 111b and the light transmittance of the control region 111b can be adjusted to be increased to a predetermined ratio according to the brightness of the light defective region.

10 is a flowchart illustrating an image quality improvement method according to an embodiment of the present invention. The image quality improving method according to an embodiment of the present invention is a method using the image quality improving apparatus 100 according to an embodiment of the present invention. The ZRF 110, the image processing unit 120, The ZRF controller 130, and the like are applied in the same manner, so that the description of these configurations will be omitted.

10, an image quality improvement method according to an embodiment of the present invention acquires an image from an image sensor 220 through which light is irradiated through a lens unit 210 and a zone collected reduction filter (ZRF) 110 (S11). Then, the image obtained by the image sensor 220 is processed by the image processing unit 120 as data (S12). The ZRF control unit 130 calculates the brightness of a plurality of regions partitioned in the image from the data processed by the image processing unit 120 (S13). The CFR control unit 130 controls the light transmittance of a region of the ZRF 110 which is divided by the LCD 111 so as to reduce the brightness difference between the regions in the image (S14).

In step S14, the ZRF controller 130 extracts a defective area as an area that deviates from a predetermined brightness difference in the area of the image acquired by the image sensor 220, Extracts a correction region as a region contributing to formation of a light defective region in the region of the sensor 220, extracts, as a control region, a region through which light to be irradiated to the correction region is transmitted from the region of the LCD 111, The light transmittance can be adjusted to be in inverse proportion to the brightness of the light defective area. A detailed description thereof is as described above with reference to Figs. 8 and 9 as an example.

When the steps S11 to S14 are completed, the image sensor 220 can acquire the image again, and the light transmittance is corrected by the LCD 111 beforehand, An image with excellent color reproducibility can be obtained.

The image quality improvement method according to an embodiment of the present invention may be performed by receiving a signal for performing an image quality improvement process according to a user's operation or a predetermined process. For example, Or may be performed as a procedure after the auto focusing, and as another example, a signal for performing the photographing process may be received and automatically performed before photographing according to a user's operation or a predetermined process.

According to the image quality improving device, the digital photographing device and the image quality improving method according to the present invention, when an excessive brightness difference exists due to light saturation or light deficiency in each area in one screen, By controlling the light transmittance of each part by ZRF (Zone Collected Reduction Filter), images with excellent sharpness and color reproducibility can be obtained.

Although the present invention has been described with reference to the accompanying drawings, it is to be understood that various changes and modifications may be made without departing from the spirit of the invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

110: ZRF 111: LCD
111a and 111b: regions 112 and 113: glass
114, 116: first polarizing plate 114a: polarizing region
115,117: Second polarizing plate 115a: Polarizing region
116a, 117a: concave and convex portions 116b, 117b: white metal
116c, and 117c: substrate 120:
130: ZRF control unit 210: lens unit
220: image sensor 221, 222: area
230: IR cut filter 240:
250:

Claims (16)

An IR cut filter disposed between the lens unit and the image sensor and transmitting the light passing through the lens unit to the image sensor so as to be irradiated to the image sensor, A liquid crystal display (LCD) having a region corresponding to a plurality of pixels as a unit is formed in the center of the image sensor, and the liquid crystal display A ZRF (Zone Collected Reduction Filter) to which first and second polarizers are attached on both sides of the first polarizer;
An image processor for processing the image obtained by the image sensor as data; And
Wherein the image processing unit calculates brightness of a plurality of regions partitioned by the image processing unit and controls a light transmittance of the LCD region to reduce a brightness difference between regions of the image, And a ZRF control unit for controlling the light transmittance of the LCD area to the minimum level or not controlling the light transmittance when the brightness difference of the plurality of areas partitioned by the image is within a normal range from the processed data, ,
The first and second polarizing plates may have a polarizing region uniformly or unevenly discontinuously formed in one direction, a plurality of discontinuous arrangements of the polarizing regions are formed in parallel, or a wire grid polarizer, A plurality of concavo-convex portions made of a light-transmissive dielectric material or polymer are patterned in a concavo-convex shape in one direction, and white metal is deposited on the substrate in a sloping manner in the same direction in each of the grooves of the convexo-concave portion.
Wherein the ZRF control unit extracts a light defective area as an area deviating from a predetermined brightness difference in the area of the image and extracts an area corresponding to the light defective area as a correction area in the area of the image sensor, Wherein the control unit extracts, as a control area, an area through which light to be irradiated to the correction area is transmitted, and adjusts the light transmittance of the control area such that the light transmittance is inversely proportional to the brightness of the light defective area. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete

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