The present invention relates to a stacked disk-shaped optical lens array, a stacked lens module and methods of manufacturing the same, especially to a stacked disk-shaped optical lens array formed by stacking at least two disk-shaped optical lens arrays.
The resin injection-compression molding technology has been widely applied to various optical produces with high requirements of precision, size and optical properties such as DVD, CD-ROM, or optical lenses. The resin injection-compression molding combines two techniques-injection molding and compression molding. A mold compression process is added into general injection molding processes. That means during the beginning of the resin casting process, the mold is not closed completely. The mold is closed by pressure after part of resin being filled into a mold cavity. The pressure is applied to melt resin material inside the mold cavity through the casting area. The processes are called “closing and clamping mold operations” and the mold cavity filling is finished by compression molding. Compared with injection molding, the residual stress is reduced, the difference in refractive index is decreased, and the optical lens element is with higher accuracy. As shown in US2008/0093756, JP2008-230005, JP2003-071874 etc., optical lens elements are produced by such molding method.
Optical lenses have been broadly used in optical systems such as optical lenses of camera phones. While assembling optical lenses or producing optical lenses, a plurality of optical lens elements with different refractions is assembled with certain air spacing for images. Thus optical axis of each optical lens element needs to be aligned precisely so as to prevent reduced resolution. Moreover, there is a certain distance arranged between the optical lens elements. It takes a lot of time and efforts to run processes and precise alignment. Thus the production can't be boosted and the cost can't be reduced. Especially the assembling of the optical lens array will influence the optical effects once the optical axis of the optical lens array is not aligned. Thus the alignment of the optical lens array is getting more important and more complicated. JP2001194508 disclosed a method for manufacturing plastic optical lens array. TW M343166 revealed a method for manufacturing glass optical lens array. After production of the optical lens array, it can be cut and divided into a single optical lens element that is used in a lens module. Or the optical lens array is assembled with other optical elements to form a lens submodule array that is divided into a single lens submodule. The lens submodule is assembled with a lens holder, an image capture device or other optical elements to form a lens module.
In manufacturing lens module arrays, U.S. Pat. No. 7,183,643, US2007/0070511, WO2008011003 etc revealed a wafer level lens module. Refer to
However, while assembling several optical lens arrays for producing lens module arrays, alignment of each optical lens array has effects on resolution of the lens module array. Refer to US2006/0249859, it revealed fiducial marks generated by infrared rays to assemble wafer level lens module. Refer to JP2000-321526, and JP2000-227505, a SELFOC lenses array is produced by assembling of height with cervice. Refer to JP2001-042104, recesses with different depth are used to prevent warpage and deformation of the micro lens array. As to U.S. Pat. No. 7,187,501, cone-shaped projection is used to stack multiple optical lens elements and produce a plastic optical lens array.
The optical lens module array used in lens assemblies of LED (light emitting diode) light sources, lens assemblies of solar energy systems, and lens modules of mobile cameras generally includes a plurality of optical lens arrays with different optical surfaces. In conventional plastic optical lens arrays assembled by projections and holes, the plastic optical lens arrays are produced by injection molding, the size of the projections and holes may change due to material shrinkage. Thus the alignment accuracy is difficult to be improved. And the optical axis of each optical lens in the plastic optical lens array is shifted and difficult to be aligned. This results in restrictions on use.
A disk-shaped optical lens array produced by resin injection-compression molding and resin casting process through a center of a disk has low inner stress and high accuracy. Moreover, a disk hole arranged at a center of the disk-shaped optical lens array is used for alignment while assembling. Thus an easy method of manufacturing an optical lens module array with high accuracy by the disk-shaped optical lens array is provided. The produced optical lens module array is used in optical lenses of phone cameras, matching requirements of yield rate and production of mass production.
Therefore it is a primary object of the present invention to provide a stacked disk-shaped optical lens array applied to optical lenses of optical systems such as camera lenses, mobile phone lenses, or a single LED optical lens.
In order to achieve above object, a stacked disk-shaped optical lens array of the present invention includes at least two disk-shaped optical lens arrays stacked and assembled by glue with a preset interval. The disk-shaped optical lens array produced by resin injection-compression molding is a round disk with a disk hole at a center thereof, but not limited to the round shape. The disk-shaped optical lens array includes a first optical surface and a second optical surface, respectively with corresponding optical divisions and non-optical divisions. The optical divisions of the first optical surface and of the second optical surface form a plurality of optical lens elements arranged in an array. At least one glue groove is disposed on a periphery of the non-optical division of at least one disk-shaped optical lens array. After the glue in the glue groove being cured, the two adjacent disk-shaped optical lens arrays are fixed and connected with each other to form a stacked disk-shaped optical lens array. Moreover, at least one alignment fixture is disposed on a periphery of the non-optical division of at least one disk-shaped optical lens array. By the alignment fixture, the two adjacent disk-shaped optical lens arrays are stacked and assembled precisely and optical axis of each optical lens element is aligned. Furthermore, the stacked disk-shaped optical lens array is coated with glue on the non-optical division so as to be assembled with other optical element arrays in a stacked way. The optical element array is an array formed by optical lenses, spacers, apertures, cover glasses, IR-cut glasses etc. After being cut, the stacked disk-shaped optical lens array is divided into a plurality of single stacked optical lens elements.
It is another object of the present invention to provide a stacked disk-shaped optical lens array applied to optical lenses of optical systems while the stacked disk-shaped optical lens array includes at least two disk-shaped optical lens arrays fixed and assembled by glue with a present interval. The disk-shaped optical lens array produced by resin injection-compression molding is a round disk with a disk hole at a center thereof, but not limited to the round shape. The disk hole of at least one disk-shaped optical lens array is disposed with a guiding structure by which the two disk-shaped optical lens arrays are stacked and assembled. Moreover, a spacer is arranged between two disk-shaped optical lens arrays to have designed air spacing. The spacer is fixed and assembled with adjacent disk-shaped optical lens array by glue.
It is a further object of the present invention to provide a stacked lens module. The stacked lens module consists of at least one stacked optical lens element, a lens holder and at least one optical element. The stacked optical lens element is produced by cutting a stacked disk-shaped optical lens array and dividing a single element from the stacked disk-shaped optical lens array. The optical element includes an optical lens, a spacer, an aperture, a cover glass, an IR-cut glass, etc.
It is a further object of the present invention to provide a method of manufacturing a stacked disk-shaped optical lens array and a stacked lens module including following steps:
According to the present method, precise stacked optical lens arrays and stacked lens modules are produced at a time. Thus precise assemblies are obtained and mass production is achieved.
Refer to
In order to located the two disk-shaped optical lens arrays 1, 2 quickly while stacking and assembling, a guiding structure 191 (291) is disposed on the disk hole 13 (23), as a notch structure shown in
The shape and the type of the glue groove 102 are not limited to round grooves, as shown in
Refer to
The stacked disk-shaped optical lens array 100 is singularized into a plurality of single stacked optical lens elements 200 by cutting.
Refer to
A method of manufacturing a stacked lens module consists of following steps:
Refer to
The first disk-shaped optical lens array 1 is a round disk with a diameter of 120 mm, having a disk hole 13 on a center thereof, a first and a second optical surfaces 11, 12 with corresponding 244 optical divisions arranged at equal intervals in an array respectively. The diameter of the disk hole 13 is 30 mm. Each optical division forms a meniscus optical lens element 10. Non-optical division on a peripheral of each optical lens element 10 is disposed with a glue groove 102, as shown in
The second disk-shaped optical lens array 2 is produced by the same method and having 244 meniscus optical lens elements 10 corresponding to the optical lens elements 10 of the first disk-shaped optical lens array 1. The second disk-shaped optical lens array 2 can be without the glue groove 102. Moreover, its non-optical division on the peripheral is arranged with two alignment cavities 262 and two alignment pins 261 as alignment fixtures, respectively corresponding to the alignment pins 161 and the alignment cavities 162 of the first disk-shaped optical lens array 1.
Refer to the steps S4, S5, and S6, while stacking and assembling the first disk-shaped optical lens array 1 and the second disk-shaped optical lens array 2, use a dispensing system (glue dispenser) to coat glue 330 over the glue groove 102 of the first disk-shaped optical lens array 1. The materials of the glue 330 are not limited but thermosetting glue or UV glue is preferred for optical systems. In this embodiment, thermosetting glue is used. Then by the alignment fixtures between the two disk-shaped optical lens arrays 1, 2 connecting with each other such as the alignment pins 161 and the alignment cavities connecting with the corresponding alignment cavities 262 and the alignment pins 261 respectively, the optical axis 101, 201 of each optical lens element 10, 20 are aligned after being stacked and assembled so as to form a stacked disk-shaped optical lens array 100 having two sets of 244 meniscus optical lens elements 10, 20 assembled precisely.
Refer to
Refer to
Refer to
For precise alignment, the first and the second disk-shaped optical lens arrays 1, 2 and the optical element array 3 are aligned and assembled by alignment fixtures 162, 261, 262, 361 so that optical axes 101 of each optical lens element 10, 20 and each image capture device 30 are aligned. After the glue 330 being cured in an oven, a stacked disk-shaped optical lens array 100 with 244 optical lens elements is produced.
Refer to
The first and the second disk-shaped optical lens arrays 1, 2 produced by the same method in the embodiment one respectively include 249 meniscus lens elements 10 and 249 bi-convex lens elements 20 arranged at equal intervals and the optical lens elements 10, 20 are corresponding to each other. The optical axes 101, 201 of the optical lens elements 10, 20 are aligned and arranged with an equal interval.
The first and the second disk-shaped optical lens arrays 1, 2 are round disks with a diameter of 120mm, each having a disk hole 13, 23 on a center thereof, and a notch-type guiding structure 191, 291. The disk hole 13, 23 and the guiding structure 191, 291 are formed by removing a down sprue stick 614 from a primary product of a disk-shaped optical lens array 61. The diameter of the disk hole 13, 23 is 30 mm and the distance between the apex angle of the guiding structure 191, 291 and the peripheral of the disk hole 13, 23 is 0.8 mm. Moreover, non-optical division on the peripheral of each optical lens element 10, 20 is arranged with a glue groove 102, 202. Three collimating lens type alignment fixtures 15 such as a bi-convex or plano-convex spherical lens element are arranged at 120 degrees around the periphery of the disk-shaped optical lens array. When laser beam passes through the collimating lens (15), it becomes a light beam parallel to the optical axis for calibration. A spacer array 313 is arranged between the first and the second disk-shaped optical lens arrays 1, 2 so as to have designed air spacing between each optical lens element 10 and each optical lens element 20.
While assembling and stacking, the glue grooves 102, 202 of the first and the second disk-shaped optical lens arrays 1, 2 are coated with glue 330 such as UV glue. Then the first disk-shaped optical lens array 1, the spacer array 313 and the second disk-shaped optical lens array 2 are put into an assembly fixture 55 for initial alignment as shown in
For precise alignment, refer to
Refer to
The first and the second disk-shaped optical lens arrays 1, 2 are produced by the same method mentioned in the embodiment one and embodiment two. A disk hole 13, 23 thereof is a square with a guiding structure 191, 291 that is a guiding angle and is formed by punching a down sprue stick 614 of a primary product of a disk-shaped optical lens array 61. Moreover, non-optical division of the first disk-shaped optical lens array 1 and of the second disk-shaped optical lens array 2 is arranged with at least one alignment through hole 17(27) corresponding to each other and used as alignment fixtures. In
While assembling and stacking, the glue groove 202 of the second disk-shaped optical lens array 2 is coated with glue 330 such as thermosetting glue (but not limited to). Then the first disk-shaped optical lens array 1 and the second disk-shaped optical lens array 2 are put into an assembly fixture 55 for initial alignment. The assembly fixture 55 is arranged with a disk-hole assembly pole 551 whose shape and position are corresponding to those of the guiding angle (192,292) of the disk hole 13, 23. Thus the first and the second disk-shaped optical lens arrays 1, 2 are initially aligned along a disk hole guiding line 104 by the disk-hole assembly pole 551 of the assembly fixture 55. Then by two alignment poles 553 of the assembly fixture 55 respectively being inserted into the alignment through holes 17, 27 of the e first and the second disk-shaped optical lens arrays 1, 2, optical axes of each lens element 10, 20 are aligned with each other, aligned with the optical axis 101. After the glue 330 being cured in an oven, a stacked disk-shaped optical lens array 100 is removed from the assembly fixture 55 and produced. By such precise alignment, stacking and assembling, the assembly time is reduced and the assembling efficiency is improved.
Refer to
The first and the second disk-shaped optical lens arrays 1, 2 are produced by the same method mentioned in the embodiment three. The difference between this embodiment and the above one is in that the non-optical divisions of the first and the second disk-shaped optical lens arrays 1, 2 are respectively are disposed with reticles 18(28) used as alignment fixture. The reticle 18(28) is formed by hair lines and the two reticles 18(28) of this embodiment can be, but not limited to, arranged at 90 degrees around the periphery of the disk-shaped optical lens array 1(2).
While assembling and stacking, similar to the embodiment three, initial alignment is achieved by the disk hole 13(23) and the guiding angle 192 (292). For precise alignment (refer to the embodiment two and
Refer to
The manufacturing processes of this embodiment are similar to those of the above embodiments. Firstly, produce a stacked disk-shaped optical lens array 100 that are assembled precisely and having a first and a second disk-shaped optical lens arrays 1, 2 glued and fixed by glue 330. The first and the second disk-shaped optical lens arrays 1, 2 respectively have 249 meniscus lens elements 10, 20 as the embodiment two. By the guiding structure and the alignment structure mentioned in above embodiments, optical axes 101, 201 of each lens elements 10, 20 are aligned and assembled precisely. After being cut and divided, 248 stacked optical lens elements 200 are produced (one is unable to be used due to under-size of the periphery), each having two meniscus lens elements 10, 20 aligned with the optical axis 101.
While assembling, the cover glass 311 is mounted into the lens holder 301 firstly. The aperture 312 is glued with the stacked optical lens element 200 and then set into the lens holder 301. For keeping designed air spacing between the IR cut glass 314 and the optical lens element 20, a first spacer 313 is disposed between the stacked optical lens element 200 and the IR cut glass 314. The image capture device 30 is preset on a circuit board 3a. In order to have designed air spacing between the IR cut glass 314 and the image capture device 30, a second spacer 313 is arranged between the IR cut glass 314 and the image capture device 30. By threads between the second spacer 313 and the lens holder 301, the above-mentioned optical elements are fixed. Lastly the image capture device 30 and the circuit board 3a are glued and fixed in the lens holder 301 to produce a stacked lens module 300. The structure of the stacked lens module 300 and the manufacturing method thereof overcomes shortcomings of conventional techniques during which each optical element needs to be adjusted, calibrated and assembled by optical instruments. Moreover, the difficulties in increasing lens resolution due to alignment of optical axes are also reduced.
Furthermore, for cost down and mass production, the stacked lens module 300 of this embodiment can be assembled in another way. As embodiment one, each optical element is produced in an array form such as disk-shaped aperture array, disk-shaped first spacer array, disk-shaped IR cut glass array etc. A plurality of disk-shaped optical element arrays is produced firstly. The disk-shaped optical element arrays are assembled and stacked precisely with the stacked disk-shaped optical lens array 100 of the present invention to form a stacked lens sub-module array. Then the stacked lens sub-module array is cut and divided into several stacked optical lens elements 200 with optical elements, as the embodiment one and the embodiment shown in
Refer to
The method of manufacturing this embodiment is the same as the one mentioned in the above four embodiments. At first, a stacked optical lens element 200 including two optical lens elements 10, 20 and glue grooves 102 is produced. Then mount a cover glass 311, an aperture 312, the stacked optical lens element 200 into a lens holder 301 to form a first optical lens group 31. A third plastic lens element 60 and a lens holder 302 are also prepared. Next the third plastic lens element 60, a spacer 313, an IR cut glass 314 and another spacer 313 is assembled into the lens holder 302 in turn. A circuit board 3a set with an image capture device 30 is assembled onto the lens holder 302 so as to form a second optical lens group 32.
In use, the first optical lens group 31 is mounted into a lens barrel (not shown in figure). By movement of the first optical lens group 31, the distance between the optical lens groups varies so as to achieve zooming effect. Thereby the stacked lens module 300 is produced easily and quickly. By virtue of mass production, the cost is reduced dramatically.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, and representative devices shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
Number | Date | Country | Kind |
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098130845 | Sep 2009 | TW | national |