Apparatus and method for aligning optical axes of lenses and assembling camera module
10293441 ยท 2019-05-21
Assignee
Inventors
Cpc classification
Y10T29/53061
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B23P21/00
PERFORMING OPERATIONS; TRANSPORTING
G03B43/00
PHYSICS
Y10T29/53022
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y10T29/4978
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B23P19/04
PERFORMING OPERATIONS; TRANSPORTING
Y10T29/49769
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
B32B41/00
PERFORMING OPERATIONS; TRANSPORTING
B23P21/00
PERFORMING OPERATIONS; TRANSPORTING
B23P19/10
PERFORMING OPERATIONS; TRANSPORTING
B23P19/04
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Provided are an apparatus and method of aligning optical axes of lenses and assembling a camera module that are capable of adjusting the optical axes of the lenses. The apparatus for aligning the optical axes of the lenses and assembling the camera module includes a support block to support a substrate at which an image sensor is installed, a displacement sensor to measure a tilted state of the image sensor, a fastener to fasten or loosen fastening components to couple a lens holder to the substrate, and a controller to control a fastening level of the lens holder by the fastener to correct a tilted state according to a measurement result of the displacement sensor. The optical axis of the lens can be rapidly and precisely adjusted and assembled by use of the above described apparatus and method.
Claims
1. An apparatus for aligning optical axes of lenses and assembling a camera module, the apparatus comprising: a support block configured to support a substrate; a lens holder configured to be fastened to the substrate by means of three or more bolts; a lens barrel attached to the lens holder; a lens mounted on the lens barrel; an image sensor installed on the substrate and configured to detect an image of a test chart through the lens; a lens clamper configured to clamp and move the lens barrel on a surface of the lens holder to match a center point of the lens with a center point of the image sensor according to the image of the test chart; a vision camera disposed above the image sensor and configured to detect an image of the image sensor through a holder hole of the lens holder, wherein the support block or the test chart is configured to be shifted to match the center point of the image sensor with a center point of the test chart according to the image of the image sensor; a displacement sensor configured to detect a tilted state of at least one of the image sensor, the lens barrel, and the substrate to generate tilt information; a bolt fastener configured to tighten the three or more bolts to fasten the lens holder to the substrate; and a controller configured to control the bolt fastener and an axis of the support block according to the tilt information to correct the tilted state of the image sensor, wherein the bolt fastener is configured to tighten the three or more bolts with different fastening levels to adjust gaps between the lens holder and the substrate.
2. The apparatus for aligning the optical axes of the lenses and assembling the camera module according to claim 1, further comprising a dispenser configured to apply an adhesive agent to one surface of the lens holder to attach the lens barrel on which the lens is mounted to the lens holder.
3. The apparatus for aligning the optical axes of the lenses and assembling the camera module according to claim 2, further comprising a UV radiator configured to radiate an ultraviolet ray to the adhesive agent and cure the adhesive agent.
4. The apparatus for aligning the optical axes of the lenses and assembling the camera module according to claim 2, further comprising an LED illuminator configured to provide uniform illumination to inspect the lens with naked eyes.
5. The apparatus for aligning the optical axes of the lenses and assembling the camera module according to claim 4, wherein the LED illuminator enables determination of whether a surface defect of the lens is present and inspection of the optical axis.
6. The apparatus for aligning the optical axes of the lenses and assembling the camera module according to claim 1, further comprising a collimator lens disposed between the lens and the test chart to reduce a focal distance of the lens.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the accompanying drawings, in which:
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DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
(16) Exemplary embodiments of the present invention will be described in detail below with reference to the accompanying drawings. While the present invention is shown and described in connection with exemplary embodiments thereof, it will be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention.
(17) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, specific structural and functional details disclosed herein are merely representative for purposes of describing exemplary embodiments of the present invention. It will be understood that when an element is referred to as being on another element, it can be directly on the other element or intervening elements may be present therebetween. In contrast, when an element is referred to as being directly on another element, there are no intervening elements present. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms a, an and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms comprises and/or comprising, or includes and/or including when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.
(18) The present invention relates to an apparatus for aligning optical axes of lenses and assembling a camera module to assemble a camera module 10 as shown in
(19) The camera module 10 includes a substrate 15 to which an image sensor 14 is attached, a lens holder 13, and a lens barrel 11.
(20) For example, the substrate 15 is wired to transmit signals, data, information, and so on. The lens holder 13 is coupled with the substrate 15. The lens barrel 11 on which a lens 12 is mounted is coupled to the lens holder 13.
(21) The lens can be focused on a precise position of the image sensor 14 when the optical axes of the assembled camera module 10 are aligned well. In contrast, the lens may be focused on an incorrect position when an error occurs in the alignment of the optical axes.
(22) The causes of generating the error in the optical axis alignment may include the followings but not limited to.
(23) A first cause is image sensor attachment tilting which can be generated when the image sensor 14 is attached to the substrate 15 via a conductive adhesive agent.
(24) A second cause is lens barrel coupling tilting which can be generated when the lens barrel 11 is coupled to the lens holder 13 fastened to the substrate 15 at which the image sensor 14 is installed.
(25) A third cause is adhesive agent curing tilting which can be generated when the adhesive agent between the lens holder 13 and the lens barrel 11 is cured through heating.
(26) Exemplary embodiments of the apparatus for aligning the optical axes of the lenses and assembling the camera module will be described with reference to the relevant drawings.
(27)
(28) Reference numeral 100 designates a test chart system test-photographed by the image sensor 14. A test chart having a test pattern detected by the image sensor 14 is installed at the test chart system 100.
(29) Reference numeral 200 designates a displacement sensor configured to detect a tilted state of a subject to generate various tilt information. The displacement sensor 200 can detect a tilted state of the camera module 10, the image sensor 14, an end section of the lens barrel 11, or the like, to generate tilt information. For example, the displacement sensor 200 can be implemented with a non-contact sensor or a confocal displacement sensor configured to precisely measure displacement of the subject using a wavelength range of light. In other instances, the displacement sensor 200 may be implemented with a two-dimensional or three-dimensional displacement sensor configured to measure the displacement while moving along the entire line or surface at a predetermined speed.
(30) Reference numeral 300 designates a lens clamper configured to clamp the lens barrel 11 (see
(31) Reference numeral 400 designates a fastener which is driven to tighten or loosen fastening components by means of which the lens holder 13 is coupled with the substrate 15. In this embodiment, for example, a bolt fastener 400 is employed to tighten or loosen bolts which are employed as the fastening components.
(32) Reference numeral 500 designates a dispenser configured to apply an adhesive agent to one surface of the lens holder 13 to couple the lens barrel 11 to the lens holder 13. Reference numeral 510 designates an UV radiator configured to radiate an ultraviolet ray to the adhesive agent to cure the adhesive agent.
(33) Reference numeral 600 designates an LED illuminator configured to illuminate the camera module 10 mounted on a support block 800 to easily check contaminations or cracks of the lens 12 with naked eyes. In addition, a test of shading and an optical axis can be observed with naked eyes by use of the LED illuminator 600.
(34) Reference numeral 700 designates a collimator lens configured to reduce a focal distance of the lens 12 to be focused to a pattern of a test chart system installed near the camera module 10.
(35) An assembled object is mounted on the support block 800. Tilting of the support block 800 can be adjusted.
(36) Reference numeral 900 designates a controller configured to control the entire components.
(37) A method of aligning optical axes of lenses and assembling a camera module to correct three kinds of tilting that causes deviation of the optical axes using the apparatus for aligning the optical axes of the lenses and assembling the camera module of the present invention will be sequentially described.
(38) Image Sensor Attachment Tilting Correction
(39) When the image sensor attachment tilting is generated, the optical axis with reference to a center of the image sensor 14 is tilted, so that a center of the lens 12 is deviated from the center of the image sensor 14 when the lens holder 13 and the lens barrel 11 are installed with reference to a vertical line of the center.
(40) An exemplary embodiment of the apparatus for aligning the optical axes of the lenses and assembling the camera module to correct the image sensor attachment tilting will be described below with reference to the relevant drawings.
(41) The support block 800 supports the substrate 15 to which the image sensor 14 is attached. The displacement sensor 200 detects the tilted state of the image sensor 14 to generate sensor tilt information. The lens holder 13 is coupled with the substrate 15 by means of fastening components. In this embodiment, for example, the lens holder 13 is fastened to the substrate 15 by at least two bolts 16. The bolt fastener 400 is driven to fasten the at least two bolts 16 to fasten the lens holder 13 to the substrate 15. The controller 900 controls the bolt fastener 400. Thereby, the support block 800 can adjust the tilting.
(42) In other words, the substrate 15 to which the image sensor 14 is attached is placed on the support block 800. The tilted state of the image sensor 14 is detected to generate the sensor tilt information by the displacement sensor 200. The controller 900 performs in accordance with the sensor tilt information to correct the tilted state of the image sensor 14, and controls the bolt fastener 400. The controller 900 may also perform controlling an axis of the support block 800 as well as the controlling of the bolt fastener 400. Thus, the lens holder 13 is fastened to or loosened from the substrate 15 accordingly.
(43) A process of aligning the optical axes using the apparatus for aligning the optical axes of the lenses and assembling the camera module of the present invention is described below.
(44) The substrate 15 to which the image sensor 14 is attached is mounted on the support block 800. The substrate 15 may be mounted in an automatic or manual manner. Here, a center of the image sensor 14 of the substrate 15 may be slightly tilted, and the tilted state is measured by the displacement sensor 200.
(45) As shown in
(46) When the tilted state of the image sensor 14 is recognized, a process of fastening/loosening the lens holder 13 is performed in consideration of the tilted state. The controller 900 controls the bolt fastener 400 to appropriately fasten or loosen the bolts 16. The controller 900 may control the bolt fastener 400 while adjusting the tilting through control of the axis of the support block 800 according to the sensor tilt information.
(47) As shown in
(48) The above description was made with reference to cross section illustration of
(49) Lens Barrel Coupling Tilting Correction Compensation
(50) Correcting the lens barrel coupling tilting by means of the apparatus for aligning the optical axes of the lenses and assembling the camera module of the present invention will be described below.
(51) Here, the support block 800 can adjust tilting, rotation and shift. The lens holder 13 is fastened to the substrate 15 such that an active region 14a of the image sensor 14 is exposed through a holder hole 13a.
(52) As shown in
(53) The displacement sensor 200 measures displacement of a plurality of points 14b on the active region 14a actually imaged by the image sensor 14 to detect the tilted state of the image sensor 14.
(54) The controller 900 is driven to control the support block 800, and ultimately tilt the image sensor 14 according to the sensor tilt information to correct the tilted state of the image sensor 14.
(55) As shown in
(56) In this case, the controller 900 is driven to shift the support block 800 (ultimately, the image sensor 14) or a test chart 110 according to the vision image checked by the vision camera 210 to match a reference point P14 of the image sensor 14 and a reference point P110 of the test chart 110.
(57) The reference point P14 of the image sensor 14 is a center point of the image sensor 14, and the reference point P110 of the test chart 110 is a center point of the test chart 110.
(58) The lens clamper 300 clamps and moves the lens barrel 11 at which the lens 12 is installed. The lens clamper 300 may be controlled by the controller 900.
(59) As shown in
(60) In this case, the controller 900 is driven to control the lens barrel 11 in accordance with the lens image to match a center point of the lens 12 with the reference point P14 of the image sensor 14.
(61)
(62) Referring to
(63) In the support block setting step (S110), the image sensor 14 is installed, and the substrate 15 to which the lens holder 13 is fastened is set to the support block 800. The lens holder 13 is fastened to the substrate 15 such the active region 14a of the image sensor 14 is exposed through the holder hole 13a. (referring to
(64) In the sensor tilting correction step (S120), the plurality of points 14b of the active region 14a of the image sensor 14 are measured by the displacement sensor 200 to generate the sensor tilt information. In order to correct the tilting of the image sensor 14, the controller 900 is driven to control the support block 800 according to the sensor tilt information.
(65) In the reference alignment step S130, in order to match the reference point P110 of the test chart 110 and the reference point P14 of the image sensor 14, the controller 900 is controlled to shift the support block 800 or the test chart 110 according to the vision image. As mentioned above, the vision image is an image of the image sensor 14 checked by the vision camera 210.
(66) The reference point P14 of the image sensor 14 may be the center point of the image sensor 14, and the reference point P110 of the test chart 110 may be the center point of the test chart 110.
(67) In the lens barrel insertion step (S140), the lens barrel 11 at which the lens 12 is installed is inserted into the lens holder 13 to which the adhesive agent is applied.
(68) In the lens barrel control step (S150) which is, for example, performed after the reference alignment step (S130) and the lens barrel insertion step (S140), in order to align the center of the lens 12 to the reference point P14 of the image sensor 14, the controller 900 is driven to control the lens barrel 11 according to the lens image. As mentioned above, the lens image is an image of the test chart 110 detected by the image sensor 14 through the lens 12.
(69) In the UV curing step (S160), after the center of the lens 12 is aligned to the reference point P14 of the image sensor 14, the adhesive agent is irradiated with an ultraviolet ray to be temporarily cured.
(70) When the camera module 10 is assembled through the above-mentioned process, the lens barrel coupling tilting is compensated, and the optical axis between the lens 12 and the image sensor 14 can be rapidly and accurately aligned.
(71) Adhesive Agent Curing Tilting Correction
(72) The adhesive agent curing tilting can be caused when the adhesive agent between the lens holder 13 and the lens barrel 11 is cured through heating to couple the lens barrel 11 to the lens holder 13. Due to non-uniformity of a thickness of the cured adhesive agent, the optical axis of the lens 12 may be deviated.
(73) The apparatus and method for aligning the optical axes of the lenses and assembling the camera module to correct the adhesive agent curing tilting will be described below with reference to the relevant drawings.
(74) The camera module 10 is mounted onto the support block 800. The camera module 10 includes the substrate 15 at which the image sensor 14 is installed, the lens barrel 11 at which the lens 12 is installed, and the lens holder 13 coupled between the substrate 15 and the lens barrel 11.
(75) The lens holder 13 is fastened to the substrate 15 such that the active region 14a of the image sensor 14 is exposed through the holder hole 13a.
(76) The lens barrel 11 is coupled to the lens holder 13 through the adhesive agent cured, for example, through heating.
(77) As shown in
(78) The displacement sensor 200 measures displacement of a plurality of points 11b on a surface of a predetermined section 11a of the lens barrel 11 near the displacement sensor 200 to detect the tilted state of the lens barrel 11.
(79) The controller 900 is driven to control the support block 800 according to the barrel tilting information to tilt the lens barrel 11 so as to correct the tilted state of the lens barrel 11.
(80) As shown in
(81) In this case, the controller 900 is driven to shift the support block 800 (ultimately, the lens 12) or the test chart 110 according to the heating vision image checked by the vision camera 210, so as to match a reference point P12 of the lens and the reference point P110 of the test chart 110.
(82) Here, the reference point P12 of the lens 12 is the center point of the lens 12, and the reference point P110 of the test chart 110 is the center point of the test chart 110.
(83) As shown in
(84) In this case, the controller 900 determines whether the optical axis of the camera module 10 is good or bad through the determination image.
(85) For example, whether the optical axis of the camera module 10 is good or bad may be determined by comparing the determination image with a predetermined reference image. In another example, whether the optical axis of the camera module 10 is good or bad may be determined by comparing optical axis measurement values of the determination image with predetermined optical axis reference values. Or, it may be determined through other various method.
(86)
(87) Referring to
(88) Specifically, as shown in
(89) When it is determined that the optical axes are not properly aligned upon photographing the test pattern, the lens barrel 11 is clamped by the lens clamper 300 to be slightly moved on the coupling surface of the lens holder 13 to adjust a tilting error. Then, as shown in
(90) After the lens barrel 11 is coupled as described above, the surface of the lens 12 is checked with naked eyes by turning on the LED illuminator 600. The LED illuminator 600 can also perform a test of the optical axis while checking the surface of the lens 12, which may have defects such as shading, defects, stains, or the like.
(91) The test chart system 100 is operated, and the test pattern is directly photographed by the image sensor 14.
(92) After completion of the adjustment, as shown in
(93) Referring back to
(94) In a barrel tilting correction step (S220), the tilting of the lens barrel 11 of the heated camera module 10 is corrected. In the barrel tilting correction step (S220), the plurality of points 11b on the end section 11a of the lens barrel 11 near the displacement sensor 200 are measured by the displacement sensor 200 to generate barrel tilting information. In order to correct the tilting of the lens barrel 11, the controller 900 is driven to control the support block 800 according to the barrel tilting information.
(95) In a reference alignment step (S230), in order to match the reference point P110 of the test chart 110 and the reference point P12 of the lens 12, the controller 900 is controlled to shift the support block 800 according to the heating vision image.
(96) In addition, the reference point P12 of the lens 12 may be the center point of the lens 12, and the reference point P110 of the test chart 110 may be the center point of the test chart 110.
(97) In a determination step (S240), the controller 900 determines whether the optical axis of the camera module 10 is good or bad through the determination image. For example, the determination step (S240) may be performed after the reference alignment step (S230).
(98) Whether the tilting error of the lens 12 is adjusted by means of the control of the controller 900 and the lenses are precisely aligned is checked through the above-mentioned process, so that the optical axis between the lens 12 and the image sensor 14 can be rapidly and precisely aligned.
(99) The adhesive agent curing tilting correction may be performed by a method of aligning optical axes of lenses and assembling a camera module according to another embodiment of the present invention.
(100) Referring to
(101) In a module heating step (S320), in order to couple the lens barrel 11 to the lens holder 13 through the adhesive agent 2 cured by the heater, the camera module 10 is heated.
(102) In a support block setting step (S330), the heated camera module 10 is set to the support block 800.
(103) In to substrate tilting correction step (S340), the controller 900 is driven to control the support block 800 according to the substrate tilting information.
(104) In a determination step (S350), the controller 900 determines whether the optical axis of the camera module 10 is good or bad through a determination image. Here, the determination image is an image of the test chart 110 detected by the image sensor 14. For example, the determination step (S350) may be performed after the substrate tilting correction step (S340).
(105) Whether the tilting error of the lens 12 is adjusted by means of the control of the controller 900 and the lenses are precisely aligned is checked through the above-mentioned process, so that the optical axis between the lens 12 and the image sensor 14 can be rapidly and precisely aligned.
(106) The invention has been described with reference to an exemplary embodiment illustrated in the drawings, but has been merely exemplified. It will be apparent to those skilled in the art that various modifications can be made to the above-described exemplary embodiments of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention covers all such modifications provided they come within the scope of the appended claims and their equivalents.