KR101679067B1 - Light emitting device and portable terminal using the same - Google Patents

Abstract

The camera module according to the present invention includes a plurality of light sources that emit light in different directions at different viewing angles, and a controller for controlling the light sources to emit light for different times.

Camera, viewing angle, light source

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device and a portable terminal using the light emitting device. 2. Description of the Related Art LIGHT EMITTING DEVICE AND PORTABLE TERMINAL USING THE SAME

The present invention relates to a camera, particularly to a camera having a light emitting means.

Modern cameras have been applied to a variety of devices in the form of miniaturized modules that store the image of the subject in an image sensor rather than a film. As a representative example thereof, a camera module mounted on a portable communication terminal can be exemplified. Due to the development of semiconductor technology, a high-picture-image sensor is applied even to a camera module mounted on a portable communication terminal.

Accordingly, the performance of the camera module mounted on the portable communication terminal and the user's demand therefor are gradually approaching to the existing camera. As means for meeting the above-mentioned demand and performance of the user, a light emitting means has been proposed.

In other words, a light emitting means called a flash or a strobe is used to support a light amount for photographing or a backlight shooting, and a light emitting diode, which is applied to a portable communication terminal, Is used.

1 is a block diagram showing a schematic configuration of a portable communication terminal incorporating a camera module and a light emitting means. 1, a conventional portable communication terminal 100 includes a camera module 130, a light emitting unit 140, a wireless transmission unit 110, a RF unit 120, a memory 150, Antenna.

The control unit 120 controls the memory 150 and the wireless transmission unit 110 to transmit and receive data stored in the memory 150 through the wireless transmission unit 110 or controls the camera module 130 and the light emitting unit 140 ) Can be provided.

The control unit 120 may include a driver for controlling the camera module 130 and the light emitting unit 140. The driver may be configured to receive the image data from the camera module 130, Receives the synchronizing signal Vsync for controlling the light emitting means 140 according to the synchronizing signal.

2 is a schematic diagram for explaining the synchronizing signal (Vsync), the operation time of the light emitting means, and frames of image data actually photographed. 2 (a) and 2 (b) are graphs showing light emitting states in different light sources, and FIG. 2 (c) shows a time interval between a sync signal and image data (image frames) FIG.

2 (d) shows the processing delay time of the image data photographed after one synchronization signal. The timing of the conventional light emitting means control is shown. In the case of using a rolling shutter, two light emitting means are continuously emitted during two synchronous signal sections for one image photographing.

That is, after the completion of each of the columns 161-1 to 161-n through which the rolling shutter passes, the camera module including the rolling shutter has a separate time 162-1 to 162-n for data processing of the corresponding column Is required. Therefore, the image data photographed between one synchronizing signal is also processed during the photographing time of another adjacent synchronizing signal. The light emitting means 140 of the camera module 130 using the conventional rolling shutter is continuously lighted while the two synchronization signals are provided.

Therefore, by emitting different light emitting means continuously for a predetermined period of time with the same intensity, the color temperature can be changed to affect the image data to be photographed. The camera module of a high pixel is more sensitive to the color temperature change because the light emitting time of the light emitting means is relatively longer than that of the camera module of the low pixel.

An object of the present invention is to provide a light emitting means capable of minimizing a color temperature change in a small camera module mounted on a portable terminal or the like using a rolling shutter.

The light emitting means for the camera module using the rolling shutter according to the present invention includes a plurality of light sources arranged in parallel to a direction in which the rolling shutter advances and each having a viewing angle directed in a direction different from each other, And a control unit for controlling the light sources to emit light at different light emission times during a photographing operation for photographing the subject and controlling the light emission time of at least two light sources to be partially overlapped with each other, One light source has a viewing angle in a direction perpendicular to a direction in which the rolling shutter advances and a viewing angle of the at least one light source may be set to a viewing angle smaller than a viewing angle in a direction in which the rolling shutter progresses.

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The light emitting means according to the present invention is set so that the viewing angles of the plurality of light sources are directed to different directions and controlled to emit light at different times so that the temperature caused by simultaneous light emission of the plurality of light sources and the resulting change in color temperature can be minimized have.

Also, it is possible to capture a bright image by centering the viewing angle of the light sources in a narrow area.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted so as to avoid obscuring the subject matter of the present invention.

3 is a block diagram illustrating a portable terminal including a light emitting unit and a camera module according to a preferred embodiment of the present invention. The portable terminal 200 according to the present invention includes a light emitting unit 210 having a plurality of light sources having different viewing angles and emitting light in different directions, a controller 230 for controlling the light sources to emit light for different times, A camera module 220 including an image sensor, and a wireless transmitting / receiving unit (RF unit) 240.

The camera module 220 may include a lens system (not shown) for converging light reflected from a subject and an image sensor for converting light converged through the lens system into image data.

FIG. 4 is a schematic view for explaining an alignment state of the light emitting means and the camera module shown in FIG. 3. FIG. Referring to FIG. 4, the light emitting unit 210 includes a plurality of light sources 211 to 213, and the light sources 211 to 213 may be light emitting diodes. In addition, the light sources 211 to 213 may be aligned so that the viewing angles are shifted, and the viewing angles may overlap each other. 4, the direction toward the subject side of the image sensor 221 and the light sources 211 to 213 is the z axis, the direction in which the rolling shutter C1 to Cn advances is the x axis, One axis is the y axis.

In the present invention, it is preferable that the light sources 211 to 213 form a narrow viewing angle with respect to the y-axis than the x-axis field-of-view range where the rolling shutter operates with respect to the image sensor 221. That is, the viewing angles of the vertical (x-axis) and horizontal (y-axis) directions are different from each other and the viewing angles of the vertical direction (y- A small amount of light can be provided in a direction perpendicular to the direction in which the rolling shutter advances. For example, if the viewing angle of the light sources 211 to 213 is set to 67.5 °, the viewing angle of the x-axis can be set to be 112.5 °.

That is, according to the present invention, since the output powers of the light sources 211 to 213 are different from each other and the light emission times are overlapped differently, the viewing angle in the y-axis direction for illuminating the subject is narrowed to increase the amount of emitted light, Can be minimized.

Therefore, the light emitting means 210 according to the present invention has a narrow field-of-view in the y-axis direction of each of the columns C1 to Cn of the rolling shutter, (211 to 213). In addition, it is preferable that the light sources 211 to 213 are arranged in parallel to the direction in which the rolling shutter operates.

The controller 230 controls the light sources 211 to 213 to operate at different powers or to be irradiated for different times. That is, the control unit 230 controls each of the light sources 211 to 213 in synchronization with the synchronization signal Vsync, and controls the driving currents of the light sources 211 to 213 differently according to time, The total light amount provided by the light source 210 can be kept constant. Therefore, the color temperature change of the light emitting means 210 according to the present invention can be suppressed.

5 is a graph for explaining an operation relationship between the light emitting unit 210 and the camera module 220 according to the present invention. 5A and 5C are graphs showing examples in which the light sources 211 to 213 are controlled with different powers according to time. The power during the entire time when the light sources 211 to 213 emit light is constant As shown in FIG. 5A to 5C illustrate the case where the light emitting means includes three light sources, but it may be configured as a light source that is more than or equal to or less than three light sources. Further, the driving current may be controlled in other forms than the states a to c of FIG.

FIG. 5D shows a synchronizing signal provided for photographing a subject. FIG. 5E is a diagram schematically showing photographing of a subject of a camera module of a rolling shutter system and data processing of a photographed image.

Figure 5d is a diagrammatic illustration of the sequential actuation of rolling shutters on the image sensor 221 with the rows R1 through Rn on which the rolling shutters run and the respective rows R1 through Rn after each row R1 through Rn, (P1 to Pn) for data processing of the data lines R1 to Rn are required. Therefore, the point at which the shooting of one synchronizing signal actually ends can be the synchronizing signal of the next order of the initial synchronizing signal. The light emitting means between the two synchronizing signals must be continuously emitted. However, instead of setting the light emitting modes or the light emitting points of the light sources constituting the light emitting means 210 differently, the present invention can increase the total light amount, However, the color temperature change can be minimized.

1 is a block diagram showing a schematic configuration of a portable terminal including a conventional camera module and light emitting means,

FIG. 2 is a graph for explaining the operation of the camera module and the light emitting means of the portable terminal shown in FIG. 1;

3 is a block diagram illustrating a schematic configuration of a light emitting unit and a camera module according to a preferred embodiment of the present invention.

FIG. 4 is a schematic view for explaining an alignment state of the light emitting means and the camera module shown in FIG. 3,

5 is a graph for explaining the operation relationship between the light emitting means and the camera module according to the present invention.

Claims (4)

A light emitting means for a camera module using a rolling shutter, A plurality of light sources arranged parallel to a direction in which the rolling shutter advances, each of the light sources having a viewing angle directed in a different direction; And a controller for controlling the light sources to emit light at different light emission times during a photographing operation for photographing a subject and controlling the light emission time of at least two light sources to overlap each other, At least one light source of the light sources has a viewing angle in a direction perpendicular to the direction in which the rolling shutter advances, Wherein the viewing angle of the at least one light source is set to a viewing angle smaller than a viewing angle in a direction in which the rolling shutter advances. The method according to claim 1, Wherein light emitting diodes having different viewing angles are used as the light sources. In a portable communication terminal, A camera module for photographing a subject using a rolling shutter; Light emitting means including a plurality of light sources arranged in parallel to a direction in which the rolling shutter advances, each of the light sources being configured such that viewing angles thereof are different from each other; And a controller for controlling driving currents applied to the light sources differently for a predetermined period of time, Wherein the light sources generate light at different light emission times during a photographing operation for photographing the subject, Wherein the controller controls the light emission time of each of the at least two light sources to be partially overlapped with each other. The method of claim 3, At least one light source of the light sources has a viewing angle in a direction perpendicular to the direction in which the rolling shutter advances, Wherein a viewing angle of the at least one light source is set to a viewing angle smaller than a viewing angle of a direction in which the rolling shutter advances.

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