KR-20260067291-A - METHOD FOR TESTING A CAMERA MODULE INCLUDING AN IMAGE SENSOR

KR20260067291AKR 20260067291 AKR20260067291 AKR 20260067291AKR-20260067291-A

Abstract

A method for testing a camera module is disclosed. The method comprises the steps of acquiring a test image generated by capturing an image quality evaluation chart according to each of a plurality of modes, and generating an evaluation result that evaluates the characteristics of the camera module using the test image, wherein the image quality evaluation chart includes a plurality of patches whose boundaries are distinguished by a plurality of ArUco markers.

Inventors

박인주
길성호
김성수
김오영
방지윤

Assignees

삼성전자주식회사

Dates

Publication Date: 20260512
Application Date: 20250508
Priority Date: 20241105

Claims (10)

As a method for testing camera modules, A step of acquiring a test image generated by capturing an image quality evaluation chart according to each of the multiple modes; and It includes a step of generating an evaluation result that evaluates the characteristics of a camera module using the above test image, and A method characterized in that the above image quality evaluation chart includes a plurality of patches whose boundaries are distinguished by a plurality of ArUco markers.
In Article 1, The above image quality evaluation chart is, It includes an inner region in which a plurality of patches are arranged and a peripheral region formed to surround the inner region, A method characterized by having a plurality of Arco markers arranged in the surrounding area to recognize the image quality evaluation chart.
In Article 1, Among the plurality of patches mentioned above, the first patch is, A first test pattern including line patterns that extend in a first direction and change color along the first direction; A second test pattern including line patterns that extend in the first direction and change color along the first direction; A third test pattern including line patterns that extend in a second direction and change color along the first direction; and It includes a fourth test pattern that includes line patterns extending in the second direction and changing color along the first direction, and The widths of the line patterns of the first test pattern and the line patterns of the second test pattern are different from each other, A method characterized in that the widths of the line patterns of the third test pattern and the widths of the line patterns of the fourth test pattern are different from each other.
In Article 1, Among the above plurality of patches, the second patch is, A first test pattern including line patterns that extend in a third direction intersecting a first direction and a second direction and change color along the first direction; and It includes a second test pattern that includes line patterns extending in a fourth direction intersecting the first direction and the second direction, and changing color along the first direction, and A method characterized in that the third direction and the fourth direction are different from each other.
In Article 1, Among the above plurality of patches, the third patch is, It includes a plurality of sub-regions arranged in the form of N rows and M columns, and Each of the above plurality of sub-regions includes a background of a specified color and a foreground of a line pattern of a specified color, and A method characterized in that the above N and the above M are natural numbers greater than or equal to 2.
In Article 1, Among the plurality of patches mentioned above, the fourth patch is, It includes multiple sub-regions having different background colors, and A method characterized by having line patterns of random directions arranged in each of the above plurality of sub-regions.
In Article 1, Among the plurality of patches mentioned above, the fifth patch is, A first sub-region containing line patterns of random directions as a grayscale image; A second sub-region expanded from the first sub-region; and A method characterized by including a third sub-region reduced from the first sub-region.
In Article 1, Among the plurality of patches mentioned above, the 8th patch is, A first test pattern comprising a plurality of line patterns that are each extended in a second direction and spaced apart from each other in a first direction; A second test pattern comprising a plurality of line patterns that are each extended in the first direction and spaced apart from each other in the second direction; A third test pattern comprising a plurality of line patterns each extending in the first direction and spaced apart in the second direction, and A fourth test pattern comprising a plurality of line patterns that are each extended in the second direction and spaced apart in the first direction, and The spacing between the plurality of line patterns of the first test pattern and the spacing between the plurality of line patterns of the fourth test pattern are different from each other, and A method characterized in that the spacing between multiple line patterns of the second test pattern and the spacing between multiple line patterns of the third test pattern are different from each other.
In Article 1, Among the above plurality of patches, the ninth patch is, A first test pattern comprising a plurality of curved patterns of a first color formed such that the spacing between them gradually widens; and A method comprising a second test pattern including a plurality of curve patterns of a second color formed such that the spacing between them gradually widens.
A method for testing a camera module including an image sensor, A calibration step for setting the default values of the above camera module; A step of acquiring a test image by photographing an image quality evaluation chart; and It includes a step of generating an evaluation result that evaluates the characteristics of a camera module using the above test image, and A method characterized in that the above image quality evaluation chart includes a plurality of patches whose boundaries are distinguished by a plurality of ArUco markers.

Description

Method for testing a camera module including an image sensor The present disclosure relates to a method for testing a camera module including an image sensor. An image sensor is a semiconductor device that converts optical information into an electrical signal. Image sensors may include Charge Coupled Device (CCD) and Complementary Metal-Oxide Semiconductor (CMOS) image sensors. A CMOS type image sensor may have multiple pixels arranged in two dimensions. Each pixel may include, for example, a photodiode (PD). The photodiode can convert incident light into an electrical signal. Recently, with the development of the computer and telecommunications industries, the demand for high-performance image sensors is increasing in various fields, including digital cameras, camcorders, smartphones, gaming devices, security cameras, medical micro cameras, robots, and automotive cameras. Camera modules used in electronic devices may include image sensors. To improve the performance and prevent defects of camera modules containing image sensors, the characteristics of the camera module may be tested. FIG. 1 is a block diagram of a camera module test system according to an exemplary embodiment of the present disclosure. Figure 2 is a diagram illustrating a color filter array included in the image sensor of Figure 1. FIG. 3 is a flowchart illustrating a method for testing a camera module according to an exemplary embodiment of the present disclosure. FIGS. 4a and 4b are drawings illustrating an image quality evaluation chart used in a camera module system according to an exemplary embodiment of the present disclosure. Figures 5a and 5b are drawings illustrating the Arco markers included in the image quality evaluation chart. FIG. 6 is a drawing illustrating an image quality evaluation chart used in a camera module system according to an exemplary embodiment of the present disclosure. Figure 7 is a table for explaining the characteristics of a camera module being inspected using an image quality evaluation chart. Figure 8 is an enlarged view of the first patch included in the image quality evaluation chart. Figure 9 is a diagram illustrating the colors used in the image quality evaluation chart. Figure 10 is an enlarged view of the second patch included in the image quality evaluation chart. Figure 11 is an enlarged view of the third patch included in the image quality evaluation chart. Figure 12 is an enlarged view of the fourth patch included in the image quality evaluation chart. Figures 13 and 14 are enlarged drawings of the fifth patch included in the image quality evaluation chart. Figure 15 is an enlarged view of the 6th and 7th patches included in the image quality evaluation chart. Figures 16 and 17 are enlarged drawings of the 8th and 10th patches included in the image quality evaluation chart. Figure 18 is an enlarged view of the 12th patch included in the image quality evaluation chart. FIG. 19 is an enlarged view of the 13th and 14th patches included in the image quality evaluation chart. FIG. 20 is a drawing illustrating an image quality evaluation chart used in a camera module system according to an exemplary embodiment of the present disclosure. Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The numerical values of the components described below are examples only, and the present disclosure is not limited to the described numerical values and can be modified in various ways. FIG. 1 is a block diagram of a camera module test system according to an exemplary embodiment of the present disclosure. Referring to FIG. 1, a camera module inspection system may include an image quality evaluation chart (100), a camera module (200), and a test device (300). The camera module (200) is the subject of the test, and the camera module (200) can photograph the image quality evaluation chart (100) and transmit the test image as result data to the test device (300). The image quality evaluation chart (100) may include a plurality of patches corresponding to the characteristics of the camera module (200), and may include a plurality of markers for recognizing the image quality evaluation chart (100). The configuration of the image quality evaluation chart (100) will be described in detail later in FIG. 4a, etc. The camera module (200) may include an image sensor (10) and may include an image processing circuit (e.g., an image processing processor) for processing an image signal output from the image sensor (10). Additionally, the camera module (200) may include a memory device, and for example, the memory device may be a non-volatile memory device. The image sensor (10) can detect light and convert it into an electrical signal, and can generate an image signal by sensing an image of a target. For example, the image sensor (10) may include a pixel array including a plurality of pixels, a read-out circuit that converts a pixel signal output from the pixel arra