KR100265495B1 - Image compensation device by optic sensor - Google Patents

Abstract

PURPOSE: An image correcting apparatus by a photo sensor is provided to correct a color temperature due to a reverse light generated when a phase of a subject is formed on a pickup element. CONSTITUTION: A pickup section(10) converts a light from a subject into an electric signal. A plurality of photo sensors(LSx) are arranged around the pickup section(10). A low luminance detector(100) discriminates a photo sensor for sensing a low luminance among the photo sensors(LSx). A high luminance detector(101) discriminates a photo sensor for sensing a high luminance among the photo sensors(LSx). A pickup driver(400) controls a starting time, an end time, and a speed which reads a pickup data of the pickup section(100). A peripheral amount ratio calculator(102) calculates a peripheral amount ratio from the electric signal from the pickup section(10). A gain compensator(200) amplifies the electric signal from the pickup section(10). A peripheral amount ratio correcting section(120) change a gain of the gain compensator(200) according to the calculated peripheral amount ratio and a reference value. A correcting signal generator(110) generates a correcting signal from a location of a reverse light and a color temperature extracted by the high luminance detector(101). An image processor(300) corrects the gain compensated signal according to the correcting signal.

Description

Image correction device by optical sensor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image correction apparatus using an optical sensor that corrects an image signal based on an amount of light detected by an optical sensor and its position information. More specifically, an optical sensor is disposed around an imaging device (CCD). Detects the optical axis of the light source incident on the lens, the presence and absence of backlight, the color temperature, the effective source and other ambient light ratios from the distribution of the optical sensor for detecting light having a certain level of intensity among the arranged optical sensors The present invention relates to an image correction apparatus using an optical sensor that provides an optimal photographed image by applying necessary corrections to an image signal input from an image pickup device using the obtained information.

In the case of photographing a subject, a part of the image having a higher luminance than that of the subject other than the subject is generated on the imaging device CCD by the so-called backlight, which is an unnecessary light source reflected around the lens in addition to the light source which is reflected by the subject and goes straight to the lens. Of course, a color different from the actual color is formed by the color temperature according to the characteristics of the backlight.

In order to solve such a problem, a backlight compensation apparatus has been proposed. A conventional backlight compensation apparatus includes: an imaging unit (CCD) 10 for converting an optical signal incident from a subject into an electrical signal, as shown in FIG. A gain compensator (AGC) 20 for compensating for the gain of the converted electrical signal; An image signal processor 30 for signal processing the gain-compensated signal and outputting it as a luminance / chromatic signal; A signal region divider 21 for dividing the output luminance signal into regions-specific signals corresponding to a screen; Triangle wave generator 22; A comparator (23) for integrating image signals divided by the regions in synchronization with a triangular wave applied from the triangular wave generator (22) and comparing the values with each other; A microcomputer 40 for determining whether or not backlighting is generated according to the comparison result and generating a control signal for adjusting the opening and closing degree of the aperture; And an aperture driver 41 for driving the aperture according to the generated control signal. It is configured to include.

In the conventional backlight compensation apparatus configured as described above, an optical signal incident from a subject is converted into an electrical signal by the image capturing unit 10 and applied to the gain compensator 20, and the gain compensator 20 The gain-compensated signal is processed by the image signal processing unit 30 to be output as a luminance signal and a color signal, of which the luminance signal is input to the signal region divider 21 and divided on the screen as shown in FIG. The comparator 23 is separated by signals corresponding to an area, and the comparator 23 is synchronized with a triangular wave output from the triangular wave generator 22 to integrate the separated signals and compare the integrated values with each other. That is, the comparator 23 compares the integrated value I (A) of the luminance signal corresponding to the area A with the value of 3 × I (D) and I (A) with 1.5 × I (B). Is output to the microcomputer 40, the microcomputer 40 according to the output confirmation results, the writing result is I (A) ≥ 3 × I (D) and I (A) ≥ 1.5 × I ( B), it is determined that the backlight is present, and outputs a control signal so that the aperture is further opened by the aperture driver 41 to increase the brightness of the entire screen.

However, the conventional backlight compensator, which is constructed and operated as described above, has a problem that when the upper part of the screen is brighter than the center, the backlight compensation is performed even when the actual subject is in the center of the screen or the light condition is not backlight. However, due to the characteristics of the lens itself, there is a phenomenon in which the peripheral portion of the image becomes darker than the central portion, but since this degree varies depending on the lens and the focal length, it is not sufficient to compensate for the uniformly reduced brightness.

In addition, when photographing a subject, back light is not only incident directly, but back light is reflected on a barrel. In this case, the brightness of the output image is caused by the flare and the color temperature of the back light. And chromaticity becomes uneven, and when the optical axis on the image pickup device deviates from the optical axis of the light source, the center of the screen is distorted, and when the ambient light ratio is changed by the surrounding environment, the overall signal gain is excessive or insufficient. In some cases, there was a problem that the image processed by the signal processing was not clear.

Accordingly, an object of the present invention is to provide a backlight compensation apparatus using an optical sensor for correcting flare and color temperature caused by backlight caused when imaging a wave body in the imaging device. Another object of the present invention is to provide an optical element correcting mechanism by an optical sensor that corrects the center shift of a screen caused by an optical axis mismatch when an object is imaged on an image pickup device. In addition, the present invention provides an image sensor to adjust an ambient light amount according to the size of an image of a subject, thereby providing an ambient light amount correcting device using an optical sensor to obtain a clear image suitable for a shooting environment.

1 is a block diagram of a conventional backlight correction apparatus,

2 is a diagram illustrating an image pickup unit, in which an optical signal is received, is divided into an arbitrary region for back light confirmation;

Figure 3 is a block diagram according to a preferred embodiment of the image correction apparatus by the optical sensor according to the present invention,

FIG. 4 shows an optical sensor arrangement that is evenly distributed throughout the imaging section of FIG.

* Explanation of symbols for main parts of the drawings

LS: Optical sensor LS _x : X-th optical sensor

10: imaging unit (CCD) 20, 200: gain compensator (AGC)

21: signal region divider 22: triangle wave generator

23: comparator 30, 300: video signal processing unit

40: MICOM 41: aperture driver

100: low luminance detector 101: high luminance detector

102: ambient light ratio calculation unit 110: correction signal generator

120: ambient light ratio correction unit 400: imaging drive unit

In accordance with an aspect of the present invention, there is provided a backlight compensation apparatus using an optical sensor, including: photoelectric conversion means for converting an optical signal incident from a subject into an electrical signal; A plurality of light sensing means disposed respectively within an effective field radius around the photoelectric conversion means for sensing incident light; Backlight detecting means for detecting a backlight position and a color temperature in an image from the distribution of said light sensing means which detected light of a predetermined intensity; And image signal processing means for correcting the signal output from the photoelectric conversion means and outputting it as an image signal according to the detected backlight position and color temperature. The optical axis correction device by the optical sensor according to the present invention comprises a photoelectric conversion means for converting an optical signal incident from a subject into an electrical signal; A plurality of light sensing means disposed respectively within an effective field radius around the photoelectric conversion means for sensing incident light; Optical axis detecting means for detecting coordinates of the optical axis from the distribution of the optical sensing means which detected light of a predetermined intensity; And control means for varying an image reading timing of the photoelectric conversion means based on the detected coordinates of the optical axis. In addition, there is another feature that is configured to include, In addition, the apparatus for correcting the ambient light amount by the optical sensor according to the present invention, photoelectric conversion means for converting the optical signal incident from the subject into an electrical signal; Amplifying means for amplifying and outputting the converted electric signal; A plurality of light sensing means disposed respectively within an effective field radius around the photoelectric conversion means for sensing incident light; Sensing means for detecting the magnitude of the effective source from the sensed intensity of light and its change; Light quantity ratio detection means for detecting an ambient light quantity ratio from an output signal of the amplifying means; Comparison means for comparing the optimal ambient light ratio corresponding to the detected effective field size with the detected ambient light ratio; And control means for varying the amplification gain of the amplifying means according to the comparison result. It is another feature that is configured to include.

In the backlight compensation apparatus using the optical sensor according to the present invention configured as described above, a plurality of adjacently disposed around the photoelectric conversion means, the light sensing the light having a light intensity of a predetermined level or more of the light signal incident from the subject From the distribution of the light detecting means, the backlight detecting means detects the position and color temperature of the backlight and the video signal processing means converts the video signal from the electric signal incident from the subject and converted in the photoelectric conversion means. The video signal corresponding to the detected backlight position is compensated for and outputted by luminance and color temperature.

In the optical axis correction device by the optical sensor according to the present invention configured as described above, a plurality of adjacently arranged around the photoelectric conversion means, to detect light having a light intensity of a predetermined level or less of the optical signal incident from the subject From the distribution of the optical sensing means, the optical axis detecting means detects the optical axis coordinates of the incident light source, and the control means compares the detected optical axis coordinates with a set center coordinate and according to the difference, the photoelectric conversion By means of varying the timing at which optical information is read out by the amount of electricity, the center of the read out image is shifted.

In addition, in the ambient light amount correcting apparatus by the optical sensor according to the present invention configured as described above, a plurality of the light sensing means are disposed adjacent to the photoelectric conversion means, to detect the light incident from the subject, respectively, The phase detection means detects the magnitude of the effective phase from the detected intensity of light and its change. On the other hand, the light quantity ratio detecting means detects the light quantity ratio between the center and the edge from the signal output from the photoelectric conversion means, and the comparing means detects the optimal ambient light ratio and the detection corresponding to the size of the detected effective field. The ambient light ratio is compared, and the control means adjusts the ambient light ratio by appropriately varying the amplification gain of the electric signal converted and output from the photoelectric conversion means.

Hereinafter, the configuration and operation of a preferred embodiment of an image correction apparatus using an optical sensor according to the present invention will be described in detail with reference to the accompanying drawings.

3 is a block diagram of a preferred embodiment of an image correction apparatus for performing backlight compensation, optical axis correction, and ambient light ratio correction by an optical sensor according to the present invention, and converting light incident from a subject into an electric signal An imaging unit 10; A plurality of light sensors LSx arranged in four directions as shown in FIG. 4 around the imaging unit 10; A low luminance detector (100) for identifying an optical sensor for detecting low luminance light among the optical sensors (LSx); A high brightness detector (101) for identifying a light sensor for detecting high brightness light among the light sensors (LSx); An imaging driver 400 for adjusting a starting point, an end point, a speed, etc. of reading the imaging data of the imaging unit 10; An ambient light quantity ratio calculating unit 102 for calculating an ambient light quantity ratio from the electrical signal converted and output from the imaging unit 10; A gain compensator (200) for amplifying and outputting the signal output from the imaging unit (10); An ambient light ratio correcting unit for varying a gain of the gain compensator 200 according to the calculated ambient light ratio and a reference value; A correction signal generator (110) for generating a correction signal from the position and color temperature of the backlight emitted from the high brightness detector (101); And an image signal processor 300 for correcting the gain-compensated signal according to the generated correction signal. It is configured to include.

In the image correction apparatus using the optical sensor according to the present invention configured as described above, the optical signal incident from the subject is formed in the imaging unit 10 through the lens is converted into an electrical signal, the imaging unit 10 An optical signal of an effective source is also simultaneously incident on a plurality of optical sensors LSx evenly disposed in the adjacent vicinity of the light source. In this state, the high brightness detection unit 101 estimates the back light position reflected by the barrel. In order to identify light sensors that have detected light having a light intensity higher than the average value of the total detected light intensities, and extract the back light generating position from the positions of the identified light sensors, and also back light detected by the light sensor. The color temperature is extracted according to the characteristics of.

The extracted backlight position and color temperature are applied to the correction signal generator 110, and the correction signal generator 110 receives a video signal that is currently processed by being processed and receives the image signal from the synchronization signal. A compensation signal is generated to compensate the backlight and the color temperature. The image signal processor 300 compensates the luminance and the color temperature of the corresponding region where the backlight is generated by the generated compensation signal and corrects it to a clean normal signal. And then print it out.

The low luminance detection unit 100 identifies the light sensors that detect light having a light intensity lower than the average value of the detected light intensities, and the light sensors identified at this time are the effective effective area of the incident light signal (effective source). Optical sensors are distributed on the boundary line of. From the positions of the optical sensors identified as described above, the low luminance detection unit 100 extracts the size (radius) of the effective source and is incident by the light intensity detected by the optical sensors located at the boundary of the effective source. The optical axis table of the light source is extracted.

When the optical axis coordinates of the light source are extracted as described above, the low luminance detection unit 100 compares the center coordinates of the predetermined screen of the imaging unit 10, and if the values do not match, correcting the error value. The position correction amount is applied to the imaging driver 400. The imaging driver 400 increases the timing of the image data read clock of the imaging unit 10 to move the image to the left side, and slightly delays the read clock to move the image to the right. And the optical axis of the incident light source are matched.

On the other hand, the size data of the effective field extracted by the low luminance detection unit 100 is transmitted to the ambient light ratio ratio correction unit 120, the ambient light ratio ratio correction unit 120 is corresponding to the current effective field size When the optimal ambient light ratio is compared with the ambient light ratio calculated by the ambient light amount calculator 102 from the signal amplified and output from the gain compensator 200, and the current ambient light ratio is low as a result of the comparison. As the gain amplification ratio of the gain compensator 200 increases from the center position of the screen output from the imaging unit 10 to the outside, the gain amplification ratio is increased to increase the ambient light ratio, and if the current ambient light ratio is high, Conversely, the amplification factor is reduced for signals away from the center of the screen. As such, the signal in which the ambient light ratio is close to the preset optimal light ratio is output as a clear video signal in which the brightness of the entire screen is harmonized with the ambient brightness while the image signal processing unit 300 undergoes the above-described backlight compensation. will be.

In the image correction apparatus using the optical sensor according to the present invention configured and operated as described above, the sensor senses a light source that causes flare or backlighting directly, and thus changes in color and contrast of the entire screen may be generated by the backlight. Accurately determine the lack of exposure of major subjects, and correct them.This is caused by the use of existing imaging equipment (camcorder) products by sharing several types of imaging devices (NTSC, PAL, Normal, etc.) for a single lens. By eliminating the center mismatch between the optical axis of the lens and the image pickup device, it is possible to improve the image blur caused by the movement of the zoom lens and the focus lens.

In addition, in the conventional lens, it is generally fixed to have an ambient light ratio of 30% or more. In the present invention, the ambient light ratio can be adjusted according to the size of an image formed in the image pickup device. It is an efficient and very practical invention in which a desired ambient light ratio can be obtained, and therefore, a design can be made without large limitation in the amount of ambient light at the time of lens design, thereby contributing to the miniaturization of the lens.

Claims (7)

Photoelectric conversion means for converting an optical signal incident from the subject into an electrical signal; A plurality of light sensing means disposed respectively within an effective field radius around the photoelectric conversion means for sensing incident light; Backlight detecting means for detecting a backlight position and a color temperature in an image from the distribution of said light sensing means which detected light of a predetermined intensity; And image signal processing means for correcting the signal output from the photoelectric conversion means and outputting it as an image signal according to the detected backlight position and color temperature. Image correction device by an optical sensor, characterized in that comprises a. The apparatus of claim 1, wherein the light having a predetermined intensity is light having a high luminance of a predetermined level or more. Photoelectric conversion means for converting an optical signal incident from the subject into an electrical signal; A plurality of light sensing means disposed respectively within an effective field radius around the photoelectric conversion means for sensing incident light; Optical axis detecting means for detecting coordinates of the optical axis from the distribution of the optical sensing means which detected light of a predetermined intensity; And control means for varying an image reading timing of the photoelectric conversion means based on the detected coordinates of the optical axis. Image correction device by an optical sensor comprising a. The image correction apparatus of claim 3, wherein the light having a predetermined intensity is light having a low luminance below a predetermined level. Photoelectric conversion means for converting an optical signal incident from the subject into an electrical signal; Amplifying means for amplifying and outputting the converted electric signal; A plurality of light sensing means disposed respectively within an effective field radius around the photoelectric conversion means for sensing incident light; Sensing means for detecting the magnitude of the effective source from the sensed intensity of light and its change; Light quantity ratio detection means for detecting an ambient light quantity ratio from an output signal of the amplifying means; Comparison means for comparing the optimal ambient light ratio corresponding to the detected effective field size with the detected ambient light ratio; And control means for varying the amplification gain of the amplifying means according to the comparison result. Image correction device by an optical sensor, characterized in that comprises a. 6. The image correcting apparatus according to claim 5, wherein the control means varies the amplification gain of the amplifying means based on the position on the photoelectric conversion means of the signal output from the amplifying means. 7. An optical sensor according to claim 6, wherein the control means increases the amplification gain of the amplifying means in proportion to the separation distance from the center position on the photoelectric conversion means of the signal output from the amplifying means. Image correction device.

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