Camera Module Inspection Chart and System Including same

Abstract

A camera module inspection chart according to one embodiment may include a chart comprising a first inspection pattern for inspecting a first camera function, a first polarizing member located above the first inspection pattern, a second inspection pattern for inspecting a second camera function, and a second polarizing member located above the second inspection pattern and having a polarization angle different from that of the first polarizing member, and a polarizing plate comprising a first polarizing plate having the same polarization angle as the first polarizing member and a second polarizing plate having the same polarization angle as the second polarizing member.

Description

Technology Field

[0001] The present invention relates to a camera module inspection chart and a system including the same, and more specifically, to a camera module inspection chart and system capable of simultaneously performing inspections on camera modules of various specifications with high inspection accuracy. Background Technology

[0002] Recently, portable devices such as smartphones, mobile phones, and PDAs, which are widely used, are actively undergoing convergence in which additional functions, such as watching movies and taking photos, are added in addition to the device's inherent functions. The camera module can be considered the most representative component driving this development toward multi-convergence.

[0003] A camera module is formed by arranging a printed circuit board, an image sensor, a driving unit, and a lens inside a housing, and the image sensor is manufactured using an image sensor such as a CCD or CMOS as a main component. Here, the camera module collects an image of an object through the image sensor and stores it as data in the memory within the device, and the stored data is converted into an image and displayed through the display unit of the corresponding portable terminal.

[0004] Furthermore, with the recent advancement of technology, not only is the resolution gradually increasing to higher pixel counts, but various additional features such as autofocus (AF) and optical zoom are also being implemented; consequently, it is becoming increasingly important to verify whether these functions operate accurately.

[0005] Generally, when manufacturing a camera module, the components are assembled and then inspected for defects; focus and resolution tests are conducted by photographing an inspection chart featuring an image with specific patterns, such as shapes.

[0006] When inspecting camera modules using an inspection chart, the inspection is generally conducted with the chart fixed to the front of the module; however, since the functions of each camera module differ, there is a difficulty in that the inspection chart used must also be manufactured to fit the specific camera module.

[0007] That is, as illustrated in Fig. 1, if a test was performed using a chart containing pattern a to test the function of a camera module, then to test the function of b camera module, since each camera module has a different angle of view and a different area to be tested, the test had to be performed using a chart containing pattern b, which is different from pattern a.

[0008] Therefore, when one or more of the chart shape, pattern position, and magnification were required by the camera module being inspected, the existing chart could not be used and a new chart had to be produced and used, which resulted in increased time and cost. The problem to be solved

[0009] Accordingly, the camera module inspection chart and the system including the same according to one embodiment are inventions designed to compensate for the problems described above, and aim to provide a camera module inspection chart and a camera module inspection system including the same that can simultaneously perform functional inspections on a plurality of camera modules using a plurality of polarizing plates. means of solving the problem

[0010] A camera module inspection chart according to one embodiment may include a chart comprising: a first inspection pattern for inspecting a first camera function; a first polarizing member located above the first inspection pattern; a second inspection pattern for inspecting a second camera function; and a second polarizing member located above the second inspection pattern and having a polarization angle different from that of the first polarizing member; and a polarizing plate comprising a first polarizing plate having the same polarization angle as the first polarizing member and a second polarizing plate having the same polarization angle as the second polarizing member.

[0011] The polarization angle of the first polarization member and the polarization angle of the second polarization member may be perpendicular to each other.

[0012] The polarization angle of the first polarizing member may be 0 degrees (horizontal) and the polarization angle of the second polarizing member may be 90 degrees (vertical).

[0013] The polarization angle of the first polarizer is 0 degrees (horizontal), and the polarization angle of the second polarizer may be 90 degrees (vertical).

[0014] The above polarizing plate may further include a motor that selectively overlaps the first polarizing plate and the second polarizing plate on the front of the chart.

[0015] The first polarizing plate is connected to one side of the motor, and the second polarizing plate is connected to the other side of the motor, so that depending on the rotation of the motor, the first polarizing plate and the second polarizing plate may optionally overlap with the front of the chart.

[0016] The above chart may further include a third inspection pattern for inspecting a third camera function and a third polarizing member located above the third inspection pattern and having a polarization angle different from that of the first polarizing member and the second polarizing member.

[0017] The above polarizing plate may include a third polarizing plate having the same polarization angle as the third polarizing member.

[0018] The above first camera function test and second camera function test may include at least one of a resolution test and an MTF (Modulation Transfer Function) test.

[0019] The first inspection pattern above includes a pattern for performing a functional inspection of the first camera module, and the second inspection pattern above may include a pattern for performing a functional inspection of the second camera module.

[0020] A camera module inspection system according to another embodiment may include a first inspection pattern for inspecting a first function, a first polarizing member located above the first inspection pattern, a chart including a second inspection pattern for inspecting the function of a second camera module and a second polarizing member located above the second inspection pattern and having a polarization angle different from that of the first polarizing member, a polarizing plate including a first polarizing plate having the same polarization angle as the first polarizing member and a second polarizing plate having the same polarization angle as the second polarizing member, and a control unit that performs a function inspection of the first camera module and the second camera module based on images of the first inspection pattern and the second inspection pattern that have passed through the polarizing plate.

[0021] The polarization angle of the first polarization member and the polarization angle of the second polarization member may be perpendicular to each other.

[0022] The polarization angle of the first polarizing member may be 0 degrees (horizontal) and the polarization angle of the second polarizing member may be 90 degrees (vertical).

[0023] The above polarizing plate may further include a motor that selectively overlaps the first polarizing plate and the second polarizing plate on the front of the chart or the front of the camera module performing the function test.

[0024] The first polarizing plate is connected to one side of the motor, and the second polarizing plate is connected to the other side of the motor. The control unit can control the motor to selectively overlap the first polarizing plate and the second polarizing plate on the front of the camera module or the front of the chart for functional testing.

[0025] The control unit may overlap the first polarizer on the front of the first camera module or the front of the chart when performing a functional test on the first camera module, and may overlap the second polarizer on the front of the second camera module or the front of the chart when performing a functional test on the second camera module.

[0026] The above camera module function test may include at least one of a resolution test and an MTF (Modulation Transfer Function) test. Effects of the invention

[0027] A camera module inspection chart according to one embodiment and a system including the same can perform functional inspections on multiple items using a single chart containing multiple inspection items, thereby saving costs due to chart integration and having the advantage of being able to measure two or more types of models at the same time. Brief explanation of the drawing

[0028] FIG. 1 is a drawing illustrating a method for inspecting a camera module according to a conventional embodiment. FIG. 2 is a block diagram illustrating some components of a camera module inspection system according to one embodiment of the present invention. FIG. 3 is a drawing illustrating one side of a chart according to one embodiment. FIG. 4 is a diagram illustrating a method for acquiring an image of a first inspection pattern placed on a chart according to one embodiment. FIG. 5 is a diagram illustrating a method for acquiring an image of a second turn placed on a chart according to one embodiment. FIG. 6 is a diagram illustrating a method of overlapping a first polarizer and a second polarizer in front of a camera module according to another embodiment. FIG. 7 is a diagram illustrating a method of overlapping a first polarizer and a second polarizer in front of a camera module according to another embodiment. Specific details for implementing the invention

[0029] The embodiments described in this specification and the configurations illustrated in the drawings are preferred examples of the disclosed invention, and various modifications that may replace the embodiments and drawings of this specification may exist at the time of filing this application.

[0030] Furthermore, the terms used herein are for the purpose of describing embodiments and are not intended to limit or / or restrict the disclosed invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

[0031] In this specification, terms such as “comprising,” “having,” or “having” are intended to indicate the existence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and do not preclude the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof; and terms including ordinal numbers such as “first,” “second,” etc. used in this specification may be used to describe various components, but said components are not limited by said terms.

[0032] Below, embodiments of the present invention are described in detail with reference to the attached drawings so that those skilled in the art can easily implement the invention. Additionally, parts of the drawings that are irrelevant to the description are omitted to clearly explain the invention.

[0033] FIG. 2 is a block diagram illustrating some components of a camera module inspection system (100) according to one embodiment of the present invention, and FIG. 3 is a diagram illustrating one side of a chart according to one embodiment. FIG. 4 is a diagram illustrating a method for acquiring an image of a first inspection pattern placed on a chart according to one embodiment, and FIG. 5 is a diagram illustrating a method for acquiring an image of a second turn placed on a chart according to one embodiment.

[0034] Referring to FIG. 2, a camera module inspection chart (110) according to one embodiment may include a chart (110) containing a specific pattern for inspecting the function of a camera module, a second polarizer (140) having different polarization angles, and a motor (120) that controls the rotational operation of the second polarizer (140) and the second polarizer (140); and a camera module inspection system (100) may include a control unit (350) that controls the camera module inspection chart (110), a first camera module (210), and a second camera module (220) and performs a function inspection of the camera module based on an image captured by the camera modules (210, 220), a communication unit (330) that transmits commands from the control unit (350) to the first camera module (210) and the second camera module (220), and the first camera module (210), the second camera module (220), and It may include a second polarizing plate (140), a storage unit (340) for storing information about the second polarizing plate (140), and a display unit (360) for displaying an image captured by the first camera module (210) and the second camera module (220) or a result analyzed by the control unit (350) to the outside.

[0035] The chart (110) may include specific patterns that can inspect various functions of the camera module. For example, it may include patterns having specific shapes required for resolution or lens focus adjustment, and may be composed of, for example, a PIMA chart specified in ISO 12233.

[0036] Therefore, since charts have specific patterns tailored for inspecting camera functions, generally, a single chart could only perform inspections on one function or one type of camera. In other words, to perform an inspection on item 'a', only a chart containing pattern 'a' could be used; similarly, to perform an inspection on item 'b', only a chart containing pattern 'b' had to be used.

[0037] However, as shown in FIG. 3, the chart (110) according to one embodiment includes a pattern a that can perform an inspection on item a and a pattern b that can perform an inspection on item b on the surface of the chart (110), so there is an advantage of being able to perform inspections on item a and item b simultaneously. This will be examined in detail through the drawings below. However, for convenience of explanation, pattern a is referred to as the first inspection pattern and pattern b is referred to as the second inspection pattern.

[0038] Although not shown in the drawing of FIG. 3, the upper part of the first pattern of FIG. 3 may include a first polarizing member capable of allowing only a specific direction of light to pass through, and the upper part of the second pattern may include a second polarizing member capable of allowing only a specific direction of light to pass through. Accordingly, the light that passes through the first polarizing member or the second polarizing member leaves only the light from which the light in a specific direction among the components of the light has been removed.

[0039] And, here, the polarization angles of the first polarization member and the second polarization member can be arranged differently from each other, specifically to form angles perpendicular to each other.

[0040] For example, if the polarization angle of the first polarizing member is 0 degrees (horizontal), the polarization angle of the second polarizing member may be 90 degrees (vertical), and conversely, if the polarization angle of the first polarizing member is 90 degrees (vertical), the polarization angle of the second polarizing member may be 0 degrees (horizontal).

[0041] And when a second polarizer (140) or a second polarizer (140) is overlapped in front of the chart (110) configured in this way or in front of the camera module to be inspected as in FIG. 4 or FIG. 5, the image acquired by the camera module can acquire only an image of a specific pattern that has passed only a specific wavelength.

[0042] That is, since the polarizer only allows light in a specific direction to pass through, an image can be acquired when the polarization angle of the polarizing member on the chart (110) and the polarization angle of the polarizer are the same, but when the polarization angle of the polarizing member on the chart (110) and the polarization angle of the polarizer are different, specifically when there is a 90-degree difference, both the horizontal light and the vertical light are blocked, so the light transmitted from the camera module does not reach the chart (110), and therefore no reflected light is acquired, so no image can be acquired.

[0043] For example, in the case of FIG. 4, the second polarizing plate (140) is overlapped with the front of the inspection chart (110) or the front of the camera module. In FIG. 4, since the polarization angle of the first polarizing member and the polarization angle of the second polarizing plate (140) are the same, the light emitted from the camera module can pass through both the second polarizing plate (140) and the first polarizing member, then be reflected by the first inspection pattern and return to the camera module.

[0044] However, since the second polarizer (140) does not have the same polarization angle as the second polarizing member, when the light emitted from the camera module passes through the second polarizer (140) and the second polarizing member located on the chart (110), there is no remaining component of light. Therefore, the light transmitted from the camera module and passing through the second polarizer (140) and the second polarizing member is not reflected and does not return to the camera module.

[0045] Accordingly, as shown in (c) of FIG. 4, the image acquired by the camera module can acquire an image of a chart with only pattern a remaining, so based on this, the control unit (350) can perform an inspection of item a or an inspection of the first camera module.

[0046] Conversely, FIG. 5 corresponds to a case where the second polarizing plate (140) is overlapped with the front of the inspection chart (110) or the front of the camera module. In FIG. 5, since the polarization angle of the second polarizing plate (140) is the same as the polarization angle of the second polarizing member, the light emitted from the camera module can pass through both the second polarizing plate (130) and the second polarizing member, then be reflected by the second inspection pattern and return to the camera module.

[0047] However, since the second polarizer (140) does not have the same polarization angle as the first polarizer, when the light emitted from the camera module passes through the second polarizer (140) and the first polarizer located on the chart (110), there is no remaining component of light. Therefore, the light transmitted from the camera module and passing through the second polarizer (140) and the first polarizer is not reflected and does not return to the camera module.

[0048] Accordingly, as shown in (c) of FIG. 5, the image acquired by the camera module can acquire an image of a chart with only the b pattern remaining, so based on this, the control unit (350) can perform an inspection of the b item or an inspection of the first camera module.

[0049] In other words, when attempting to inspect a specific function of a camera module, only one pattern must exist on the chart; therefore, according to conventional technology, it was not possible to include multiple patterns for multiple items in a single chart.

[0050] However, in the case of a camera module inspection chart (110) according to one embodiment, although the chart (110) simultaneously includes inspection patterns for various inspection items, the image acquired by the camera module using a polarizer can acquire an image of the chart containing only one specific pattern, so that an inspection can be performed.

[0051] Therefore, by utilizing this principle, multiple patterns for multiple items can be included in a single chart, which saves costs associated with chart integration and also offers the advantage of being able to measure two or more models simultaneously.

[0052] FIG. 6 is a drawing illustrating a method of overlapping a first polarizer and a second polarizer in front of a camera module according to another embodiment, and FIG. 7 is a drawing illustrating a plan view of the arrangement according to FIG. 6.

[0053] Referring to FIGS. 6 and FIGS. 7, a camera module inspection system (300) according to one embodiment may place a second polarizing plate (140) and a motor including the second polarizing plate (140) on the front of a camera module to be inspected, thereby selectively overlapping the second polarizing plate (140) or the second polarizing plate (140) on the front of the camera module.

[0054] That is, when a first inspection pattern is required to perform an inspection of the first item, the second polarizing plate (140) can be placed in front of the camera module (200) by rotating the connecting part (121) using the motor (120).

[0055] In this case, the light transmitted from the camera module (200) passes through the second polarizer (140) and only the vertical or horizontal component remains, and since the polarization angle of the second polarizer (140) and the polarization angle of the first polarizing member located above the first inspection pattern are the same, the light transmitted from the camera module (200) can reach the first inspection pattern.

[0056] Therefore, the camera module (200) can capture an image of the first inspection pattern. However, in the case of the second inspection pattern, since the polarization angle of the second polarizing member located above the second inspection pattern is perpendicular to the polarization angle of the second polarizing plate (140), the light transmitted from the camera module (200) is completely blocked as it passes through the second polarizing plate (140) and the second polarizing member, so the light cannot reach the second inspection pattern. Therefore, the camera module (200) cannot acquire an image of the second inspection pattern.

[0057] Conversely, if a second inspection pattern is required to perform an inspection of the second item, the second polarizing plate (140) can be placed in front of the camera module (200) by rotating the connecting part (121) using the motor (120).

[0058] In this case, the light transmitted from the camera module (200) passes through the second polarizer (140) and only the vertical or horizontal component remains. Since the polarization angle of the second polarizer (140) and the polarization angle of the second polarizing member located above the second inspection pattern are the same, the light transmitted from the camera module (200) can reach the second inspection pattern. Therefore, the camera module (200) can capture an image of the second inspection pattern.

[0059] However, in the case of the first inspection pattern, the polarization angle of the first polarizing member located above the first inspection pattern is perpendicular to the polarization angle of the second polarizing plate (140). Therefore, the light transmitted from the camera module (200) is completely blocked as it passes through the second polarizing plate (140) and the first polarizing member, so the light cannot reach the first inspection pattern. Consequently, the camera module (200) cannot acquire an image of the first inspection pattern.

[0060] In other words, through this method, images of the first or second inspection pattern can be selectively acquired, thereby providing the effect of being able to selectively inspect different items using a single chart.

[0061] And in FIGS. 6 and 7, the inspection items for the first inspection pattern and the inspection items for the second inspection pattern are described based on a single camera module, but as shown in FIG. 2, the inspection for the first inspection pattern can be set as an inspection for the first camera module (210), and the inspection for the second inspection pattern can be set as an inspection for the second camera module (220).

[0062] That is, the first inspection pattern and the second inspection pattern may be patterns for different functional inspections for a single camera or patterns for different camera modules for a single item.

[0063] Returning to FIG. 1 to describe other components of the camera module inspection system (300), the storage unit (340) may store a chart (110) and camera modules (210, 220). The storage unit (340) may also store information regarding the initial position of the lens, such as the MTF values ​​detected by the control unit (350).

[0064] Accordingly, the storage unit (340) may be implemented as at least one of a non-volatile memory device such as a cache, ROM (Read Only Memory), PROM (Programmable ROM), EPROM (Erasable Programmable ROM), EEPROM (Electrically Erasable Programmable ROM), and flash memory, a volatile memory device such as RAM (Random Access Memory), or a storage medium such as a hard disk drive (HDD) and CD-ROM, but is not limited thereto.

[0065] Additionally, the storage unit (340) may be a memory implemented as a separate chip from the processor described later in relation to the control unit (350) described later, or it may be implemented as a single chip with the processor.

[0066] The control unit (350) can control the overall functions of the camera module (210, 220) and the camera module inspection system (300).

[0067] Specifically, the control unit (350) can analyze image data of the chart (110) acquired by the camera module (210, 220) and perform an inspection of various functions of the camera module (210, 220).

[0068] For example, the control unit (350) can detect the resolution for each lens position by analyzing image data acquired by the camera modules (210, 220). Based on this, the control unit (350) can find the optimal lens position for each camera module (210, 220) based on the detected resolution.

[0069] Additionally, the control unit (350) can transmit a signal to the motor (120) using the communication unit (330) to selectively position the second polarizing plate (140) and the second polarizing plate (140) in front of the camera module according to the inspection purpose.

[0070] For example, if an inspection of the first camera module (210) is required, the second polarizing plate (140) can be controlled to be positioned in front of the first camera module (210) so that the first camera module (210) can capture a first inspection pattern for inspecting the function of the first camera module (210), and conversely, if an inspection of the second camera module (220) is required, the second polarizing plate (140) can be controlled to be positioned in front of the second camera module (220) so that the second camera module (220) can capture a second inspection pattern for inspecting the function of the second camera module (220).

[0071] The display unit (360) can display image data of the chart (110) generated by the camera module (210, 220).

[0072] The display unit (360) can display image data of the chart (110) generated according to lens position, thereby providing information to the user so that they can visually identify information about the chart (110). Accordingly, the display unit may include various display devices.

[0073] The communication unit (330) can transmit and receive signals between the control unit (350), the camera module (210, 222), and the motor (120).

[0074] So far, through the drawings, we have examined the features and effects of a camera module chart according to one embodiment and a camera module inspection system including the same.

[0075] When inspecting camera modules using an inspection chart according to conventional technology, the inspection is generally conducted with the chart fixed to the front of the camera module; however, since the functions of each camera module differ, there is a difficulty in that the inspection chart used for inspection must also be manufactured to fit the camera module.

[0076] In other words, therefore, when one or more of the chart shape, pattern position, and magnification were required by the camera module being inspected, the existing chart could not be used and a new chart had to be produced and used, which resulted in increased time and cost.

[0077] However, the camera module inspection chart according to one embodiment and the system including the same can perform functional inspections on multiple items using a single chart containing multiple inspection items, thereby saving costs due to chart integration and having the advantage of being able to measure two or more types of models at the same time.

[0078] Although the embodiments described so far have been explained by limited examples and drawings, those skilled in the art can make various modifications and variations from the description above. For example, appropriate results may be achieved even if the described techniques are performed in a different order than described, and / or components such as the described system, structure, device, circuit, etc. are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents. Therefore, other embodiments and equivalents to the claims are also included within the scope of the claims set forth below. Explanation of the symbols

[0079] 100: Camera Module Inspection Chart 110: Chart 120: Motor 130: First polarizer 140: Second polarizer 200: Camera Module Inspection System 210: 1st camera module 220: Second camera module 230: Communications Department 240: Storage section 250: Control unit 260: Display unit

Claims

Claim 1 A camera module inspection chart comprising: a first inspection pattern for inspecting a first camera function; a first polarizing member positioned above the first inspection pattern; a second inspection pattern spaced apart from the first inspection pattern and for inspecting a second camera function different from the first camera function; and a second polarizing member positioned above the second inspection pattern and having a polarization angle perpendicular to the first polarizing member. Claim 2 delete Claim 3 A camera module inspection chart according to claim 1, wherein the polarization angle of the first polarizing member is 0 degrees (horizontal) and the polarization angle of the second polarizing member is 90 degrees (vertical). Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A camera module inspection chart according to claim 1, further comprising a third inspection pattern for a third camera function inspection and a third polarizing member located above the third inspection pattern and having a polarization angle different from that of the first polarizing member and the second polarizing member. Claim 8 A camera module inspection chart according to claim 1, wherein the first camera function inspection and the second camera function inspection include at least one of a resolution inspection and an MTF (Modulation Transfer Function) inspection. Claim 9 A camera module inspection chart according to claim 1, wherein the first inspection pattern includes a pattern for performing a functional inspection of a first camera module, and the second inspection pattern includes a pattern for performing a functional inspection of a second camera module. Claim 10 A camera module inspection system comprising: a first inspection pattern for inspecting a first camera module function; a first polarizing member positioned above the first inspection pattern; a second inspection pattern spaced apart from the first inspection pattern and for inspecting a second camera module function different from the first camera module function; a chart including a second polarizing member positioned above the second inspection pattern and having a polarization angle perpendicular to the first polarizing member; a polarizing plate including a first polarizing plate having the same polarization angle as the first polarizing member and a second polarizing plate having the same polarization angle as the second polarizing member; and a control unit for performing inspection of the first camera module function and inspection of the second camera module function based on images of the first inspection pattern and the second inspection pattern that have passed through the polarizing plate. Claim 11 delete Claim 12 A camera module inspection system according to claim 10, wherein the polarization angle of the first polarizing member is 0 degrees (horizontal) and the polarization angle of the second polarizing member is 90 degrees (vertical). Claim 13 A camera module inspection system according to claim 10, further comprising a motor that selectively overlaps the first polarizing plate and the second polarizing plate on the front of the chart or the front of the camera module performing a functional inspection. Claim 14 In claim 13, the first polarizing plate is connected to one side of the motor and the second polarizing plate is connected to the other side of the motor, and the control unit controls the motor to selectively overlap the first polarizing plate and the second polarizing plate on the front of the camera module or the front of the chart for functional testing, thereby forming a camera module inspection system. Claim 15 A camera module inspection system according to claim 14, wherein the control unit overlaps the first polarizer on the front of the first camera module or the front of the chart when performing a functional inspection of the first camera module, and overlaps the second polarizer on the front of the second camera module or the front of the chart when performing a functional inspection of the second camera module.

Images