KR100896803B1 - Inspection Chart for Camera Module Inspection System - Google Patents

Abstract

Since the inspection chart for the camera module inspection apparatus according to the present invention can perform the MTF inspection and the resolution inspection at the same time through the inspection pattern consisting of a plurality of inspection lines, there is an effect that greatly reduces the inspection time of the camera module.

Description

Test chart for inspection apparatus of camera module

The present invention relates to an inspection chart for a camera module inspection apparatus, and more particularly, to an inspection chart for a camera module inspection apparatus capable of performing an MTF method and a resolution inspection at the same time.

As for mobile terminals such as mobile phones and PDAs, the convergence of additional functions such as movie watching and photography, as well as the inherent functions of the terminals, is actively progressed, and one of the leading camera modules as a multi-convergence is being developed. (CAMERA MODULE) is the most representative.

The camera module not only increases resolution to a higher pixel but also additionally implements various additional functions such as auto focusing (AF) and optical zoom.

In general, a camera module (CCM: COMPACT CAMERA MOUDULE) mounted on a portable terminal is manufactured in a small size and manufactured using an image sensor such as a CCD or a CMOS as a main component. Here, the camera module collects an image of an object through an image sensor and stores the image on the memory of the device, and the stored data is displayed as an image through the display unit of the corresponding portable terminal.

In addition, a normal camera module is manufactured by a method such as COB (CHIP ON BOARD), COF (CHIP ON FLEXIBLE).

In this case, the camera module adjusts the distance between the lens and the image sensor and then fixes the camera module to focus.

After the focus adjustment of the camera module, the inspector arranges the focused camera module in the inspection apparatus and determines whether the camera module is defective by checking the resolution through a resolution test method.

However, in the related art, since the apparatus for adjusting the focus of the camera module and the test apparatus for determining the defect are separately configured, the operator prepares for the defect of the camera module only after the operator moves and arranges the focused camera module to the test apparatus. There is a problem that is completed.

Therefore, in the related art, since the time for moving the focused camera module, the time for placing the camera module in the test apparatus, and the like, there is a problem that the production yield is lowered.

In addition, since the MTF test and the resolution test are conventionally performed separately, there is a problem that a chart for each test should be provided.

An object of the present invention is to provide an inspection chart for a camera module inspection apparatus capable of performing MTF method and resolution inspection at the same time.

According to the present invention, a center inspection unit including an origin pattern, an inspection pattern disposed at a predetermined interval with respect to the origin pattern, an outer origin pattern disposed around the center inspection unit, and a predetermined distance from the outer origin pattern Including an outer inspection pattern including an outer inspection pattern disposed, at least some of the inspection pattern camera module inspection including a plurality of inspection lines are formed to maintain the thickness and separation distance at a predetermined ratio for the resolution inspection and MTF inspection Provide an inspection chart for the device.

The inspection pattern may include a horizontal inspection pattern in which the plurality of inspection lines are disposed in a vertical direction with respect to the origin, and a vertical inspection pattern in which the plurality of inspection lines are arranged in a horizontal direction with respect to the origin. Some of the pattern or the horizontal inspection pattern may be set as a pattern for MTF inspection according to the focal length of the camera module.

The apparatus may further include a threshold pattern disposed to be spaced apart from the origin pattern by a predetermined distance, and the area of the central inspection unit may be set through the threshold pattern.

The outer inspection unit may be disposed at an edge of the inspection chart, and the outer inspection unit may include an outer origin pattern, an outer inspection pattern arranged around the outer origin pattern to perform a resolution inspection, and a critical region of the outer inspection unit. It may include a threshold pattern for checking.

Since the inspection chart for the camera module inspection apparatus according to the present invention can perform the MTF inspection and the resolution inspection at the same time through the inspection pattern consisting of a plurality of inspection lines, there is an effect that greatly reduces the inspection time of the camera module.

In addition, since the present invention utilizes a part of the inspection pattern as a pattern for MTF inspection, the algorithm for MTF inspection and resolution inspection is simplified, thereby reducing the inspection time of the camera module.

In addition, according to the present invention, since the pattern on which the MTF inspection and the resolution inspection are performed is integrated in the inspection pattern, the area of the inspection chart can be greatly reduced, and the free space is secured.

1 is a perspective view of a camera module according to a first embodiment of the present invention, Figure 2 is a cross-sectional view of the camera module shown in FIG.

As shown in FIGS. 1 and 2, the camera module 10 according to the present embodiment includes a housing 13 having a female thread 13a formed on an inner circumferential surface thereof, and a printed circuit board disposed below the housing 13. 14), a male thread 12a is formed on an outer circumferential surface thereof, the body 12 coupled to the housing 13, the lens 11 disposed on the body 12, the printed circuit board 14, It is disposed between the body 12 includes an image sensor 15 for sensing the image passing through the lens (11).

The body 12 is assembled to the housing 13 by screwing, and the body 12 is rotated in a clockwise or counterclockwise direction, so that between the lens 11 and the image sensor 15 The distance is adjusted, and the focus of the camera module 10 is adjusted by adjusting the distance between the lens 11 and the image sensor 15.

In addition, a filter 17 is disposed between the image sensor 15 and the lens 11 to prevent a frequency of an area that cannot be detected by the image sensor 15 from being input.

In particular, a tooth 16 is formed on an outer circumferential surface of the body 12, and the body 12 can be more easily rotated through the tooth 16.

3 is a perspective view showing a camera module inspection apparatus according to an embodiment of the present invention, Figure 4 is a perspective view showing the inside of the camera module inspection apparatus shown in Figure 3, Figure 5 is a guide shown in Figure 4 The module is shown in perspective view.

3 to 5, the camera module inspection apparatus 100 according to the present embodiment includes a booth 110, a light source module 120 disposed inside the booth 110 to generate light, and the booth. The inspection module 150 disposed inside the 110 and the camera module 10 is disposed, and the guide module 130 disposed in the booth 110 to guide the moving direction and the moving distance of the light source module 120. ).

The booth 110 blocks the external light to uniformly provide the amount of light source provided to the inspection module 150.

The light source module 120 includes an LED light source 122 generating light by an applied current, a frame 124 on which the LED light source 122 is fixed, and a chart disposed on the LED light source 122 (not shown). The chart is for focus adjustment and resolution inspection of the camera module 10, it is disposed on the lower side of the LED light source (122).

Here, the components of the LED light source 122 is a general technology to those skilled in the art, detailed description thereof will be omitted.

The guide module 130 may include a guide rail 132 coupled to the frame 124 of the light source module 120, and a fixed rail 134 coupled to the booth 110 and engaged with the guide rail 132. And a guide lever 135 disposed at one end of the guide rail 132 to transfer the guide rail 132.

Here, the guide rail 132 is disposed in the up / down direction so that the frame 124 can be moved up / down, disposed in a plurality of positions of the frame 124, in the present embodiment the quadrilateral shape The light source module 120 is disposed at four corners of the frame 124, which is configured to move upward and downward while maintaining horizontality.

The fixed rail 134 and the guide rail 132 are engaged in a ball screw shape, and a spiral tooth 132a is formed on an outer circumferential surface of the guide rail 132. A ball (not shown) engaged with the guide rail 132 is disposed.

In addition, the guide rail 132 is linearly moved in the up / down direction by the rotation of the guide lever 135, the up / down linear transfer distance is determined by the pitch of the spiral teeth 132a Therefore, the feeding distance can be controlled more precisely.

Figure 6 is a perspective view of the inspection module shown in Figure 3, Figure 7 is a perspective view before the operation of the module jig 160 shown in Figure 6, Figure 8 is a perspective view after the operation of the module jig shown in Figure 7, 9 is a perspective view of the sensor of Figure 6, Figure 10 is a plan view of the focusing unit shown in Figure 6, Figure 11 is another perspective view showing the state after the operation of the inspection module in Figure 6, Figure 12 6 is a perspective view after the operation of the characteristic inspection unit shown in FIG.

6 to 11, the inspection module 150 according to the present embodiment includes a module jig 160 in which the camera module 10 is disposed and a module jig 160 arranged in the camera module 10. Clamp 180 is disposed on the upper side of the module jig 160 in which the camera module 10 is disposed and moved up / down to fix the camera module 10. ), A focusing unit 190 disposed above the clamp 180 and coupled to the body 12 of the camera module 10, and disposed near the module jig 160 and, if necessary, the camera. And a characteristic inspection unit 200 which is moved between the module 10 and the focusing unit 190.

The module jig 160 includes a base 162, a jig 164 in which the camera module 10 is disposed, and a moving mechanism 165 for moving the jig 164 forward and backward.

The base 162 is fixed to the booth 110, the jig 164 is arranged to reciprocate linearly toward the focusing unit 190 by the moving mechanism, the movement mechanism 165 is the embodiment In the pneumatic cylinder is used, unlike the present embodiment various kinds of transfer apparatus can be used. In this case, the jig 164 is linearly moved by the pneumatic cylinder to the rear in which the focusing unit 190 is disposed.

The position of the jig 164 is detected by a contact sensor or an optical sensor, and when the moved position of the jig 164 is not the correct position, the controller detects this and returns the jig 164 to the initial position. . In particular, when the jig 164 is not moved to the correct position, the tester is notified of the lighting or buzzer sound.

The clamp 180 is positioned between the focusing unit 190 and the jig 164 to fix the camera module 10 disposed on the jig 164, and includes a clamp plate 182 and the And a clamp guide 184 fixed in the up / down direction with respect to the clamp plate 182 and a moving mechanism 186 for moving the clamp plate 182 up and down.

A clamp hole 185 is disposed in the clamp plate 182, and the clamp hole 185 is disposed above the camera module 10 moved backward. That is, when the camera module 10 is moved toward the focusing unit 190 by the jig 164, the light generated by the light source module 120 is transferred to the camera module 10. The clamp hole 185 is formed. In addition, a focusing hole 195 is formed in the focusing unit 190 to allow light generated by the light source module 120 to pass therethrough.

The focusing unit 190 includes a focusing plate 192 in which the focusing hole 195 is formed, a guide bar 193 guiding a moving direction of the focusing plate 192, and the focusing plate 192. A moving mechanism 196 for moving downward, a sensor 197 for detecting the position of the focusing plate 192, a disk 199 disposed on the focusing plate 192, and the disk 199. And a connect pin 198 coupled to the teeth 16 formed on the body 12 of the camera module 10 and a rotating mechanism (not shown) for rotating the disk 199.

The focusing plate 192 is linearly reciprocated in the up / down direction by the moving mechanism 196. In this embodiment, the moving mechanism 196 includes a step motor 196a fixed to the upper frame 166. And a screw 196b rotated by the step motor, and the screw 196b is engaged with the clamp plate 182 for movement.

Here, when the screw 196b is rotated by the rotational force generated by the step motor 196a, the female thread formed on the clamp plate 182 (not shown 0 and the male thread of the screw 196b are engaged with each other. The clamp plate 182 is moved upward or downward.

In particular, the clamp plate 182 is penetrated by the guide bar 193. When the clamp plate 182 is moved up and down, the guide bar 193 is in the horizontal direction of the clamp plate 182. The clamp plate 182 is guided in an up / down direction in a state in which movement to the camera is suppressed so that the camera module 10 and the connect pin 198 are close to each other.

The sensor 197 is disposed on the clamp guide 184 to detect the upper limit position or the lower limit position of the clamp plate 182, and in this embodiment, the upper limit position of the clamp plate 182 is sensed to detect the clamp. The distance between the plate 182 and the jig 164 is minimized to keep the moving distance of the clamp plate 182 at a minimum distance.

When the clamp plate 182 is moved downward, the connect pin 198 and the teeth 16 of the body 12 are coupled, and the disk 199 is rotated by the power generated by the rotating mechanism. The body 12 is rotated.

Here, the rotating mechanism may be implemented in various forms, and although not shown, in the present embodiment, a step motor disposed on the clamp plate 182 and a belt or a chain connecting the disc 199 and the shaft of the step motor may be used. It is composed.

The characteristic inspection unit 200 is selectively operated to inspect the foreign matter of the camera module 10, the column 202 disposed near the module jig 160 and fixed to the base 162 and And a rotatable arm 204 disposed on the column 202 and moved between the jig 164 and the focusing unit 190 and disposed on the rotatable arm 204 to generate light for property inspection. A light source (not shown) and a rotation mechanism 206 disposed in the column 202 to rotate the rotatable arm 204 by a predetermined angle.

Wherein the characteristic inspection unit 200 by providing the light generated through the light source to the camera module 10, to inspect the dust or foreign matter infiltrated into the camera module 10, although not shown, In the example, the light source is disposed with an LED light source.

In addition, the rotating mechanism 206 is for rotating the rotatable arm 204 by a predetermined angle, a step motor or a ball / hydraulic cylinder may be used.

Meanwhile, in the present exemplary embodiment, an operation unit 140 in which electrical components (not shown) are disposed for the control under the base 164 is disposed, and the operation unit 140 automatically or inspects the inspection of the camera module 10. This can be done manually, and for this purpose, buttons 142 and 144 are arranged for automatic inspection or manual inspection.

In addition, the inspection module 150 is connected to a numerical operation device (for example, a computer) equipped with an image display device (for example, a monitor), and an image input to the camera module 10 is transferred to the image display device. Is displayed.

13 is a flowchart illustrating an inspection method of an apparatus for inspecting a camera module according to a first embodiment of the present invention.

6 to 13, a step (S10) in which the camera module 10 is disposed on the jig 164 by an inspector and a step in which the module jig 160 in which the camera module 10 is disposed are moved ( S20, the step of fixing the moved camera module 10 by the clamp 180 (S30), the focusing unit 190 is moved to the upper side of the clamp 180 (S40), and Detecting an operation failure of the camera module 10 (S50), and if it is determined that there is no operation failure of the camera module 10, adjusting the focus of the camera module 10 (S60), and the camera. After the focus of the module 10 is adjusted, the step of verifying the resolution of the camera module 10 (S70) and the step of checking the characteristics of the camera module 10 (S80).

In this case, the inspecting of the camera module 10 includes the steps S10, S20, S30, S40 of setting the inspection module 150 for the inspection of the camera module 10, and the inspection module ( It comprises a step (S50) (S60) (S70) (S80) that the focus adjustment and defect inspection of the camera module 10 set in 150 is performed.

Looking at the process of setting the camera module 10, the inspector arranges the camera module 10 in the jig 164, the camera module 10 disposed in the jig 164 is a focusing unit 190 It is moved rearward.

After the control unit disposed on the manipulation unit 140 senses the correct position of the jig 164, the clamp 180 is moved downward to fix the camera module 10 to the clamp 180. After fixing the camera module 10, the focusing unit 190 is moved downward, and the connecting pin 198 disposed on the focusing unit 190 and the teeth 16 of the body 12 of the camera module 10. ) Are combined with each other to complete setting for focusing and inspection of the camera module 10.

The light generated by the light source module 120 disposed in the booth 110 may be a chart disposed in the light source module 120, a focusing hole 195 of the disk 199, and a clamp hole of the clamp plate 182. It passes through the 185 and passes through the lens 11 of the camera module 10.

Here, the pattern for focus adjustment of the MTF method and the pattern for resolution checking which will be described later are simultaneously disposed in the chart.

If the jig 164, the clamp plate 182, and the focusing plate 192 are not moved to the correct position, the controller detects the jig 164, the clamp plate 182, and the focusing unit. After each of the plates 192 is repositioned, movement to the home position is attempted again.

Next, the camera module 10 set as described above supplies current to the camera module 10 through the headboard 170 to determine whether the camera module 10 is operated, and the camera module 10 by the supplied current. ), The control unit performs a short circuit or disconnection inspection of the camera module 10 through the current input to the camera module 10, and determines a defect thereof. (S50)

Here, the control unit processes the numerical operation device with the signal input to the camera module 10 and displays an image on the screen display unit.

Next, the control unit performs a focus control to adjust the distance between the lens 11 and the image sensor 15 by rotating the connect pin 198 disposed in the focusing unit 190. The control unit for inputting the image transmitted through the lens 11 to the image sensor 15 generates a captured image through the image input to the image sensor 15.

In this case, the controller determines the captured image through a MTF (Modulation Transfer Function) method, and adjusts the focal length between the lens 11 and the image sensor 15.

The MTF is a measure of how the spatial frequency input is deformed in the process of generating an original image through the lens and on the film or image sensor surface.

14A is an exemplary view showing an input image according to an embodiment of the present invention, FIG. 14B is an exemplary view showing an output image according to FIG. 14A, and FIG. 15 is an MTF method value according to the present embodiment. It is a graph.

Referring to FIGS. 14A and 14B, when an image as shown in FIG. 14A is input through the image sensor 15, an output image of the image as shown in FIG. 14B may be obtained, which is higher in resolution and contrast than a signal obtained by the original input image. You will get a low image.

In this case, if the brightest part of the input source, that is, the maximum exposure amount is Emax, the minimum exposure amount is Emin, the maximum exposure amount in the output image is Dmax, and the minimum exposure amount is Dmin,

The contrast of the input spatial frequency is

Ri = (Emax-Emin) / (Emax + Emin)

Can be expressed as

The contrast of the output spatial frequency is

Ro = (Dmax-Dmin) / (Dmax + Dmin)

It can be expressed as

Here, MTF = Ro / Ri, and since the MTF value is a value representing an input / output contrast ratio, the maximum value is 1, the minimum value is 0, and sometimes is expressed in%. In particular, as the MTF value approaches 1, the sharpness of the contrast is high, and as it approaches 0, the MTF value decreases.

In particular, according to the Nyquist theory, if the frequency of the input signal is half of the Nyquitm limit of the input equipment, the input signal can be accommodated. However, if the frequency is higher than this, the input equipment does not accept all the input signals. I can't.

Thus, when the input signal is a pair of black and white, when the frequency of the input signal is high, an aliasing phenomenon occurs in which the input signal is deformed into dark gray and light gray, and the aliasing occurs. The moire phenomenon or maze phenomenon, such as a wave pattern, may appear due to the phenomenon.

The controller may determine that the focus adjustment is completed when the MTF value is greater than or equal to a predetermined value (for example, 90%) by calculating the MTF value, and compare the captured image with the focused moiré pattern. The focus of the camera module 10 may be adjusted. (S60)

When the initial adjustment of the camera module 10 is performed, the controller rapidly moves the lens 11 to the vicinity of the set focal length, and then finely moves the lens 11 near the focal length to adjust the focus adjustment time. Shorten.

In this case, when the body 12 is rotated to focus on a pattern of a chart having a constant frequency bandwidth, data of a graph as shown in FIG. 15 is obtained, and a predetermined region for the maximum MTF value of the graph is set to an optimal focus. do.

In particular, the focus set through the above process is an optimal focus in the camera module 10, but resolution or resolution performance cannot be known. You can check it.

Next, the controller performs a resolution check immediately in the state where the camera module 10 in which the focus adjustment is completed is disposed.

In this case, resolution test is called resolution test or TV measurement, and various kinds of lp / mm (lp is the line pair per mili meter; indicates the number of lines drawn in 1mm, also called the space frequency, and 1 lp / mm is 1mm space This is a test of how many lines can be distinguished from the chart on which a black line of 0.5mm and a white line of 0.5mm are formed). For example, if the chart is formed while varying the thickness of about 100 to 1600 copies, and then the image is photographed through the camera module 10, the areas where the moirés are generated by combining the lines are generated. The point up to the point immediately before the moiré is not generated is determined as the maximum resolution of the camera module 10.

Here, the controller reads the image for resolution checking from the chart, and compares the spatial frequency input to the image sensor 15 with the set day value, thereby distinguishing the resolvable line from the moire.

If the resolution obtained through the resolution test is higher than the set resolution, the controller determines the focused camera module 10 as "PASS", otherwise, determines "FAIL". (S70)

Next, the control unit performs a foreign matter inspection on the camera module 10 that passed the resolution inspection, and the control unit moves the characteristic inspection unit 200 to the upper side of the camera module 10 for the foreign matter inspection. Rotate

Here, the focusing unit 190 is raised to an initial position before the feature inspection unit 200 is rotated, and after the feature inspection unit 200 is rotated after the movement of the focusing unit 190, the light source therein Is lit to supply light to the camera module 10.

And the control unit receives the light supplied from the characteristic inspection unit 200 to inspect whether the image sensor 15 or the camera module 10 is foreign matter, the light generated by the characteristic inspection unit 200 When the chart like the light source module 120 is not arranged, white light is supplied when the light source is turned on, and light is not supplied by blocking the outside when the light source is turned off.

Thus, when the light source is turned on and the light is supplied, the controller checks the detected frequency at each pixel of the image sensor 15 to detect the black spot and the pixel size of the black spot, and the size of the black spot is greater than or equal to a set value. In this case, or when the pixel size of the black spot is greater than or equal to the set value, it is determined as bad.

In addition, by detecting the detected frequency at each pixel, a red or blue point is detected instead of a white point, and it is determined that the red point or the blue point has a magnitude or frequency greater than or equal to a set value.

Next, when the light source is turned off, the frequency input to the image sensor 15 is sensed to detect the number and size of the white spots other than the black spot in each pixel, and when the size or the number of the detected white spots is greater than or equal to a set value. It is judged as bad, and even when the size or number of red or blue dots is greater than or equal to the set value, it is determined as bad. As described above, in the present embodiment, the characteristic inspection and the foreign substance inspection are performed through the luminance of the characteristic inspection unit 200 according to the light.

On the other hand, an adhesive or fixing member is disposed on the body 12 and the housing 13 of the camera module 10 to prevent rotation of the body 12, the fixing of the body 12 after the focus adjustment It may be carried out at any time after the resolution test or after the property test.

Next, when the characteristic test is completed, the module jig 160 is horizontally moved to the front where the inspector is located, and the inspector may separate / move the camera module 10 from which the test is completed from the module jig 160. have.

On the other hand, each step is automatically performed by the control unit, the inspector can monitor the focus adjustment, the resolution test, the characteristic test, etc. of the camera module 10 through the screen display unit, despite the malfunction Due to this, the camera module can be extracted.

In addition, the inspector may immediately remove the defective camera module by interrupting the inspection process through the operation unit 140 even during the automatic inspection of the camera module 10.

16 is a front view showing a camera inspection chart according to an embodiment of the present invention.

Referring to FIG. 16, the inspection chart 300 according to the present embodiment is formed separately from the center inspection unit 302 and the center inspection unit in which focus adjustment and resolution inspection of the camera module 10 are performed, and thus the camera module 10 is formed. It includes an outer inspection unit 304 for examining the outer phenomenon of the.

The center inspection unit 302 is an origin pattern 310 disposed at the center portion, an inspection pattern 320 disposed at the periphery of the origin pattern 310 to perform MTF and TV main measurement simultaneously, and the center. And a threshold pattern 330 for setting a threshold of the inspection unit 302.

Here, the origin pattern 310 is formed in a + shape, and the controller recognizes the + pattern of origin pattern 310 near the center of the inspection chart 300 to adjust the focus and the TV main inspection. The inspection area of the central inspection unit 302 is set.

The inspection pattern 320 is used to simultaneously perform the focus adjustment through the MTF method and the resolution test through the TV present method, and in the vertical direction while maintaining a constant thickness and distance ratio of the plurality of inspection lines 322. The horizontal inspection pattern 324 is arranged, and the vertical inspection pattern 326 arranged in the horizontal direction while maintaining a constant thickness and distance ratio of the plurality of inspection lines 322.

The horizontal inspection pattern 324 is composed of a plurality of inspection lines 322, the thickness of each inspection line 322 is formed to become thicker with a predetermined ratio as the distance away from the origin pattern 310, The separation distance between the inspection lines 322 is also formed to increase equal to the increase rate of the thickness. Thus, the horizontal inspection pattern 324 is formed closer to the origin pattern 310 and is expanded to be farther from the origin pattern 310.

In particular, the horizontal inspection pattern 324 is arranged in a vertical direction with respect to the origin pattern 310.

The vertical inspection pattern 326 is formed in the same manner as the horizontal inspection pattern 324 and is arranged in a horizontal direction with respect to the origin.

In particular, in the present embodiment, the horizontal inspection pattern 324 is disposed above the origin pattern 310, the vertical inspection pattern 326 is disposed on the left side of the origin pattern 310, and the threshold pattern ( 330 is disposed on the right side of the origin pattern 310.

The threshold pattern 330 is for setting the area of the central inspection unit 302, it is natural that the position movement with respect to the origin pattern 310 according to the camera module 10 is possible.

In addition, the horizontal inspection pattern 324 or the side of the vertical inspection pattern 326 may be displayed a number or a scale indicating the resolution, which is intended for the inspector to check the resolution by looking at the resolution display.

The outer inspection unit 304 is separated from the central inspection unit 302 and disposed on the inspection chart 300. In the present embodiment, the outer inspection unit 304 is disposed at four corners of the inspection chart 300.

Here, the outer inspection unit 304, unlike the central inspection unit 302, receives a signal projected to the side of the camera module 10, and determines the input image, and determines the tilt and peripheral inspection of the input image do.

That is, even though the spatial frequency input to the central inspection unit 302 is normal, the camera module 10 may be defective by determining a case where the spatial frequency input through the side of the lens is distorted.

Here, the outer inspection unit 304 is disposed near the edge of the inspection chart 300, as in the configuration of the central inspection unit 302, and the outer origin pattern 360 for inspecting the distortion, and the outer origin pattern 360. It includes an outer inspection pattern 370 disposed in the periphery to perform a TV main inspection, and a threshold pattern 330 for identifying a critical region for inspection of the inspection chart 300.

Therefore, the outer inspection unit 304 disposed at each corner of the inspection chart 300 may perform the resolution inspection by comparing the input spatial frequency with the stored spatial frequency.

In particular, in the present embodiment, even if the deviation between the resolution of the central inspection unit 302 and the resolution of the outer inspection unit 304 is greater than or equal to a predetermined value, the controller determines the camera module 10 as defective.

In addition, in the case of the threshold pattern 330, when the normal spatial frequency is not input and the spatial frequency is input in a distorted form, the controller determines the camera module 10 as defective.

On the other hand, the inspection chart 300 according to the present embodiment performs the MTF inspection using the inspection pattern 320 consisting of a plurality of inspection lines 322, instead of forming a separate pattern for the MTF inspection.

That is, reference numeral 350 is an area set for MFT inspection in this embodiment, and takes a part of the horizontal inspection pattern 324 and uses it as an MTF pattern 350 for MTF inspection as shown in FIG. 14A.

In this case, the inspection lines 322 are disposed in the horizontal inspection pattern 324 or the vertical inspection pattern 326 so that the resolution is gradually increased, and an MTF pattern is separately arranged for each focal length. The MTF patterns of various resolutions may be set using the test pattern 320 without the need to do so.

That is, the MTF pattern 350 is defined according to a region arbitrarily set among the inspection patterns 320.

On the other hand, at the edge of the inspection chart 300, a distortion inspection unit 390 for limiting the outer region of the inspection area and detecting distortion of the spatial frequency is formed.

17 is a front view showing an inspection chart according to another embodiment of the present invention.

Referring to FIG. 17, unlike the exemplary embodiment of the inspection chart 400, the inspection pattern 320 is disposed radially with respect to the origin pattern 310.

The horizontal inspection pattern 324 is disposed on the upper and lower sides of the origin pattern 310, and the vertical inspection pattern 326 is disposed on the left and right sides of the origin pattern 310, respectively.

In addition, the threshold pattern 330 is disposed between the horizontal inspection pattern 324 and the vertical inspection pattern 326, and each of the threshold patterns 330 is also disposed symmetrically with respect to the origin pattern 310.

1 is a perspective view showing a camera module according to a first embodiment of the present invention

2 is a cross-sectional view of the camera module shown in FIG.

3 is a perspective view showing a camera module inspection apparatus according to an embodiment of the present invention

4 is a perspective view showing the inside of the camera module inspection apparatus shown in FIG.

5 is a perspective view showing the guide module shown in FIG.

6 is a perspective view of the inspection module shown in FIG.

7 is a perspective view before operation of the module jig 160 shown in FIG.

8 is a perspective view after the operation of the module jig shown in FIG.

9 is a perspective view showing the sensor of FIG.

10 is a plan view showing the focusing unit shown in FIG.

11 is another perspective view showing a state after the operation of the inspection module in FIG.

12 is a perspective view after the operation of the characteristic inspection unit shown in FIG.

13 is a flowchart illustrating a test method of an apparatus for inspecting a camera module according to a first embodiment of the present invention.

14A is an exemplary view illustrating an input image according to an embodiment of the present invention.

14B is an exemplary view illustrating an output image according to FIG. 14A.

15 is a graph showing MTF method values according to the present embodiment

16 is a front view showing the inspection chart for the camera inspection according to an embodiment of the present invention

17 is a front view showing an inspection chart according to another embodiment of the present invention.

<Brief description of the symbols for the main parts of the drawings>

10: camera module 11: lens

12 body 13 housing

14: printed circuit board 15: image sensor

16: tooth 100: camera module inspection device

110: booth 120: light source module

130: guide module 140: control panel

150: inspection module 160: module jig

162: base 164: jig

170: headboard 180: clamp

190: focusing unit 200: characteristic inspection unit

300: inspection chart 302: central inspection unit

304: outer inspection unit 310: origin pattern

320: inspection pattern 322: inspection line

324: horizontal inspection pattern 326: vertical inspection pattern

330: critical pattern

Claims (7)

A central inspection unit including an origin pattern and inspection patterns spaced apart from each other by a predetermined distance from the origin pattern; An outer inspection unit including an outer origin pattern disposed around the center inspection unit, and an outer inspection pattern disposed at a predetermined interval from the outer origin pattern; At least a portion of the inspection pattern inspection chart for a camera module inspection apparatus including a plurality of inspection lines are formed so that the thickness and separation distance is maintained at a predetermined ratio for resolution inspection and MTF (Modulation Transfer Function) inspection. The method of claim 1, The inspection pattern is A vertical inspection pattern in which the plurality of inspection lines are arranged in a horizontal direction with respect to the origin; And a plurality of inspection lines including a horizontal inspection pattern arranged in a vertical direction with respect to the origin. The method of claim 2, And a part of the vertical inspection pattern or the horizontal inspection pattern is set as a pattern for MTF (Modulation Transfer Function) inspection according to the focal length of the camera module. The method of claim 1, And a threshold pattern disposed to be spaced apart from the origin pattern by a predetermined distance, and setting an area of the central inspection unit through the threshold pattern. The method of claim 1, The outer inspection unit inspection chart for the camera module inspection device disposed on the corner of the inspection chart. The method of claim 1, The outer inspection unit Outer origin pattern, An outer inspection pattern disposed around the outer origin pattern and performing a resolution inspection; An inspection chart for a camera module inspection device including a threshold pattern for identifying a critical region of the outer inspection unit. The method of claim 1, An inspection chart for a camera module inspection apparatus further includes a distortion inspection unit for detecting a distortion phenomenon of the inspection chart on the outermost side of the inspection chart.

Images