TWI703032B - Attatching method - Google Patents

Abstract

An attaching method is used to attach a first lens and a second lens. The first lens has a concave curved surface, and the second lens has a convex curved surface. The attaching method includes following steps. Attach sealant at the edge of one of the concave curved surface of the first lens and the convex curved surface of the second lens. Make active alignment for the first lens and the second lens and attach the first lens and the second lens through the sealant at the edge to form a lens group. Cure the sealant to form a wall at the edge, and the concave curved surface, the convex curved surface and the wall form a space with an inlet. Fill liquid optically clear adhesive in the space. Seal the inlet of the wall by a sealing sealant。

Description

Fitting method

The present disclosure relates to a lens group and a bonding method thereof, particularly to the bonding between a curved lens and a curved lens.

In some optical modules, a lens group composed of multiple lenses is used. For example, two lens lenses can be laminated to form a lens group by two lenses.

The conventional assembly technology of the lens group is to use optical clear adhesive (OCA) of the sheet material. The thickness of the optical transparent glue of the sheet is uniform and fixed and cannot be adjusted. This is suitable for the case where the bonding surfaces between the lenses are flat. When the bonding surface between the lenses is curved, the uniformity of the bonding pressure of the optical clear glue of the sheet on the curved surface is difficult to control, and after the lenses are bonded, the Active Alignment cannot be performed, which affects the lenses. The overall optical imaging quality of the group.

One technical aspect of this disclosure is related to a bonding method.

According to an embodiment of the present disclosure, a bonding method is used for bonding a first lens and a second lens. The first lens has a concave curved surface, and the second lens has Convex surface. The bonding method includes the following steps. Coat the sealant on the edge of one of the concave curved surface and the convex curved surface. The first lens and the second lens are actively aligned, and the concave curved surface of the first lens and the convex curved surface of the second lens are bonded by the frame glue to form a lens group. The sealant is cured to form a retaining wall, wherein the concave curved surface, the convex curved surface and the retaining wall of the lens group form a glue injection space with an injection port. Pour liquid transparent optical glue into the glue injection space. Seal the injection port of the retaining wall with the sealing glue.

In one or more embodiments, the step of actively aligning the first lens and the second lens in the above bonding method further includes the following steps. Load and fix the first lens. Load the second lens. Move the second lens to the alignment position so that the first optical axis of the first lens is aligned with the second optical axis of the second lens.

In one or more embodiments, the step of injecting liquid transparent optical glue into the glue injection space in the above bonding method further includes the following steps. Provide a sealable chamber, and set a tank in the chamber, and the tank contains liquid transparent optical glue. Place the lens group that has been actively aligned into the chamber. Seal and evacuate the chamber. Dip the injection port of the lens group into liquid optical transparent glue. Break the vacuum and inject the liquid transparent optical glue into the glue injection space.

In one or more embodiments, in the above-mentioned bonding method, before the step of sealing the injection port of the retaining wall with a sealant, the following steps are further included. Fill the transparent glue layer through the injection port by dispensing glue.

In one or more embodiments, in the above-mentioned bonding method, the length of the injection port of the retaining wall is less than a quarter of the total length of the retaining wall.

In one or more embodiments, in the above bonding method, the area of the concave curved surface is equal to the area of the convex curved surface.

Another technical aspect of the present disclosure relates to a lens group.

According to an embodiment of the present disclosure, a lens group includes a first lens, a second lens, a retaining wall and a transparent glue layer. The first lens has a concave curved surface. The second lens has a convex curved surface. The convex surface fits the concave surface. The retaining wall is located between the concave surface and the convex surface. The retaining wall is set as a closed loop at the edge of the concave surface and the convex surface. The concave curved surface, the convex curved surface and the retaining wall form a glue injection space. The transparent glue layer is filled in the glue injection space. The first lens and the second lens have a first optical axis and a second optical axis respectively, and the second optical axis is aligned with the first optical axis.

In one or more embodiments, in the above lens set, the material of the transparent glue layer is different from the material of the retaining wall.

In one or more embodiments, the material of the first lens or the second lens of the lens group includes glass or transparent plastic.

In one or more embodiments, the material of the retaining wall of the lens set includes acrylic polymer material or silicone.

In summary, the bonding method disclosed in the present disclosure can go through a two-stage bonding step, which can first perform active alignment between the lenses, and then perform further bonding between the lenses. After the bonding between the lenses is made by frame glue as a retaining wall, liquid optical transparent glue can be injected between the two lenses by vacuum to complete the bonding. The use of liquid optical transparent glue improves the uniformity of bonding pressure. Injecting by vacuum method can avoid the generation of mixed bubbles and avoid affecting the result of active alignment.

100: method

110-160: steps

200: lens group

210: lens

220: concave surface

230: lens

240: convex surface

250: retaining wall

260: injection port

270: Transparent glue layer

300: Chamber

310: tank

320: Liquid optical transparent glue

L-L: Line segment

The advantages and drawings of the present disclosure should be understood by the following embodiments and with reference to the accompanying drawings. The description of these diagrams is merely a list Therefore, it should not be considered as limiting the individual implementation modes or limiting the scope of the invention patent application.

Fig. 1 shows a flowchart of a bonding method according to an embodiment of the present disclosure; and Figs. 2A to 7B show schematic diagrams of a lens group in different steps of the bonding method according to an embodiment of the present disclosure Figures 2A, 3A, 4A, 5A, 6A, and 7A show schematic top views of the lens set, and Figures 2B, 3B, 4B, 5B, 6B, and 7B show schematic cross-sectional views of the lens set corresponding to a line segment in the LL direction.

The following is a detailed description of the embodiments with the accompanying drawings, but the provided embodiments are not used to limit the scope of the disclosure, and the description of the structure operation is not used to limit the order of its execution, any recombination of components The structure and the devices produced with equal effects are all covered by this disclosure. In addition, the drawings are for illustrative purposes only, and are not drawn according to the original dimensions. To facilitate understanding, the same or similar elements in the following description will be described with the same symbols.

Secondly, the terms "include", "include", "have", "contain", etc. used in this article are all open terms, meaning including but not limited to.

In this disclosure, in order to improve the uniformity of the bonding pressure caused by the traditional use of optically clear adhesive (OCA) for the bonding between the curved surfaces, and the inability to actively align the curved surfaces Bit problem. Especially when the lens to be fitted has a curved surface, the result of the active alignment will affect the overall optical imaging quality.

Please refer to Figure 1. FIG. 1 shows a flowchart of a bonding method 100 according to an embodiment of the present disclosure. The bonding method 100 is used for bonding two lens sets with corresponding concave and convex curved surfaces. For the purpose of illustration, reference may be made to FIGS. 2A to 7B at the same time to show the schematic top view and the schematic side view of the lens group in different steps. Figures 2A, 3A, 4A, 5A, 6A, and 7A show schematic top views of the lens set, and Figures 2B, 3B, 4B, 5B, 6B, and 7B show schematic cross-sectional views of the lens set corresponding to a line segment in the L-L direction.

FIG. 2A is a schematic top view of a process of the lens assembly in the bonding method 100, and FIG. 2B is a schematic cross-sectional view corresponding to a line segment of the lens assembly in FIG. 2A in the L-L direction. Specifically, in this embodiment, the bonding method 100 is to bond the first lens 210 and the second lens 230. For the purpose of illustration, in Figure 2A, the second lens 230 is omitted to illustrate the setting of the frame glue on the first lens 210 and the transparent glue between the first lens 210 and the second lens 230 in the subsequent steps. Distribution. Similar to the cross-sectional schematic diagram in Figure 2B, the lens groups in Figures 3B, 4B, 5B, 6B and 7B correspond to the lens groups in Figures 3A, 4A, 5A, 6A, and 7A, respectively. For the purpose of simple description, the line segment LL will not be repeated on the figure.

Please refer to Figure 2A and Figure 2B first. As shown in the figure, the lens to be attached includes a first lens 210 and a second lens 230. The first lens 210 has a concave curved surface 220 and the second lens 230 has a convex curved surface 240. Both the first lens 210 and the second lens 230 are lenses. The first lens 210 has a first optical axis, and the second lens 230 has a second optical axis. In order to stabilize the quality of optical imaging, In the process of method 100, the first lens 210 and the second lens 230 must be actively aligned. This corresponds to that the first optical axis of the first lens 210 and the second optical axis of the second lens 230 must be aligned.

Please also refer to Figure 1. In the bonding method 100, a sealant is applied to the edge of the concave curved surface 220 of the first lens 210 in step 110. The coating method of the sealant is shown in Figure 2A. The sealant forms a retaining wall 250 on the edge of the concave curved surface 220. In some embodiments, the sealant may also be coated on the edge of the convex surface 240 first.

Back to Figure 1. In step 120, the first lens 210 and the second lens 230 are actively aligned, and the retaining wall 250 is cured after the active alignment is completed, so as to fit the first lens 210 and the second lens 230 together. Specifically, the active alignment step uses the principle of optical axis to make the light rays pass through the first lens 210 and the second lens 230 respectively, and confirm that the first optical axis of the two rays of light passing through the first lens 210 and the second lens 230 respectively With the second optical axis, the center point of the alignment is obtained by using the first optical axis and the second optical axis, and the alignment deviation is further corrected.

Regarding the active alignment of the first lens 210 and the second lens 230 in step 120, specifically, in some embodiments, the first lens 210 may be loaded on a machine that performs active alignment, and the first lens 210 The position of the lens 210 is fixed. The edge of the concave curved surface 220 of the first lens 210 has been coated with sealant. Subsequently, the second lens 230 is movably loaded, and the second lens 230 is moved into the first lens 210. Subsequently, the process of active alignment is performed to allow the light to pass through the first lens 210 and the second lens 230. At the same time, the positions of the first lens 210 and the second lens 230 are fine-tuned to confirm the image quality, and the second lens 230 is moved to An alignment position, so that the first optical axis of the first lens 210 is aligned with the second optical axis of the second lens 230, and the active alignment of the first lens 210 and the second lens 230 is completed. After that, Then, the first lens 210 and the second lens 230 can be attached to the aligned position.

In some embodiments, different from step 110 and step 120, it is also possible not to apply sealant on the edge of the concave curved surface 220 of the first lens 210, but to complete the active alignment of the first lens 210 and the second lens 230 first . After the active alignment is completed, the alignment position information of the second lens 230 is memorized first, and then the second lens 230 is removed. Then, sealant is applied to the concave curved surface 220 of the first lens 210 to form the retaining wall 250, and then the second lens 230 is restored to the aligned position to complete the concave curved surface 220 of the first lens 210 and the convex curved surface 240 of the second lens 230 fit. In some embodiments, the alignment position information may include the relative position information between the first lens 210 and the second lens 230, and the central axis of the convex surface 240 of the second lens 230 and the concave surface facing the first lens 210. The solid angle between the central axis of the curved surface 220.

In some embodiments, different from step 120, after coating the frame glue on the edge of the concave curved surface 220 of the first lens 210 to form the retaining wall 250, the convex curved surface 240 of the second lens 230 can be attached to the concave through the retaining wall 250. Curved surface 220, and pre-cured retaining wall 250. At this time, although the first lens 210 and the second lens 230 are roughly fixed together, there can still be a small range of movement between the first lens 210 and the second lens 230. In this way, the first lens 210 and the second lens 230 can be substantially fixed while performing the active alignment process as described above.

After the active alignment is completed, the positional relationship between the first lens 210 and the second lens 230 is as shown in FIG. 2A and FIG. 2B. The retaining wall 250 is arranged along the edges of the concave curved surface 220 of the first lens 210 and the convex curved surface 240 of the second lens 230, but an opening is left as an injection port 260.

Back to Figure 1, go to step 130, the retaining wall formed by the sealant 250 is completely cured, so as to form a fully cured retaining wall 250 with an injection port 260 between the first lens 210 and the second lens 230. The completely solidified retaining wall 250 will make the first lens 210 and the second lens 230 no longer have a positional deviation, maintaining the result of active alignment. The concave curved surface 220 of the first lens 210, the convex curved surface 240 of the second lens 230, and the retaining wall 250 form a glue injection space, as shown in FIG. 2B. The glue injection space has an injection port 260, and then liquid optically clear adhesive (LOCA) can be filled into the glue space through the injection port 260 to further bond the first lens 210 and the second lens 230.

In this embodiment, the method of injecting liquid transparent optical glue into the glue injection space between the first lens 210 and the second lens 230 is carried out by vacuuming and breaking the vacuum. Please go back to Fig. 1 and go to step 140. The injection port 260 should be immersed in the liquid optical transparent glue 320 in a vacuum.

As shown in FIGS. 3A and 3B, FIG. 3A is a schematic top view without showing the second lens 230, and FIG. 3B is a schematic cross-sectional view corresponding to FIG. 3A. The lens group formed by bonding the first lens 210 and the second lens 230 through the barrier wall 250 is placed in the sealed chamber 300, and the chamber 300 has a tank 310 in which the liquid optical transparent glue 320 is contained. The sealed chamber 300 is evacuated, so that the glue injection space between the first lens 210 and the second lens 230 is also evacuated.

Then progress to Figure 4A and Figure 4B. FIG. 4A is a schematic top view of the second lens 230 not shown, and FIG. 4B is a schematic cross-sectional view corresponding to FIG. 4A. As shown in the figure, the injection port 260 is immersed in the liquid optical transparent glue 320. At the same time, it can be noticed that the glue injection space connected to the injection port 260 is a vacuum.

Please go back to Figure 1, go to step 150, break the vacuum to make it liquid The optical transparent glue 320 is sucked into the glue injection space from the injection port 260.

Specifically, please refer to FIG. 5A and FIG. 5B at the same time. FIG. 5A is a schematic top view of the second lens 230 not shown, and FIG. 5B is a schematic cross-sectional view corresponding to FIG. 5A. As shown in the figure, the originally sealed chamber 300 breaks the vacuum, and the first lens 210 and the second lens 230 injection space are originally vacuum. After the vacuum is broken, the atmospheric pressure allows the liquid optical transparent glue 320 contained in the tank 310 to pass through The injection port 260 is sucked into the glue injection space to form a transparent glue layer 270.

The bonding method 100 is suitable for bonding curved surfaces with close areas. In this embodiment, the concave curved surface 220 and the convex curved surface 240 have close areas, and the liquid optical transparent glue 320 is convenient to be injected into the glue injection space from the injection port 270. In some embodiments, the area of the concave curved surface 220 is the same as the area of the convex curved surface 240. In some embodiments, the concave curved surface 220 and the convex curved surface 240 have similar curvatures.

Before the transparent glue layer 270 is cured, since the transparent glue layer 270 is formed of the liquid optical transparent glue 320, the bonding pressure can be evenly distributed on the transparent glue layer 270. The amount of liquid optical transparent glue 320 used in the vacuum breaking method can be changed according to different active alignment results, so the problem of excessive or insufficient glue can also be avoided. In addition, the transparent glue layer 270 formed by the filled liquid optical transparent glue 320 is not affected by the surface undulation of the first lens 210 or the second lens 230, and the generation of bubbles is reduced. In this way, after the transparent adhesive layer 270 is cured, the result of the active alignment in the aforementioned step 120 will not be affected.

In order to be able to hold the liquid optical transparent glue 320 well, the size of the injection port 260 of the glue injection space is limited, so that the liquid optical transparent glue 320 can be filled between the first lens 210 and the second lens 230 in the largest area. In some embodiments, the length of the injection port 260 is less than the total length of the retaining wall 250. One quarter of the length.

Please go back to Figure 1 and go to step 160 to cure the transparent glue layer 270 formed by the liquid optical transparent glue 320 between the first lens 210 or the second lens 230, and then seal the injection port 260 with a sealing glue to avoid leakage Glue or debris invades from the injection port 260 and damages the transparent glue layer 270.

Please refer to FIGS. 6A and 6B at the same time. FIG. 6A is a schematic top view of the second lens 230 not shown, and FIG. 6B is a schematic cross-sectional view corresponding to FIG. 6A. As shown in the figure, after the first lens 210 and the second lens 230 are removed from the tank 310, there is a transparent glue layer 270 between the first lens 210, the second lens 230 and the retaining wall 250, and the injection port 260 is not yet seal. At this time, the transparent glue layer 270 formed by the liquid optical transparent glue 320 can be cured first, and whether there is a need for filling, for example, whether the transparent glue layer 270 is damaged near the injection port 260. If necessary, a glue coating process can be used to repair the lack of glue in the transparent glue layer 270 at the injection port 260. For example, the transparent glue layer 270 can be filled through the injection port 260 by dispensing.

Then it progresses to FIG. 7A and FIG. 7B. FIG. 7A is a schematic top view of the second lens 230 not shown, and FIG. 7B is a schematic cross-sectional view corresponding to FIG. 7A. As shown in the figure, the injection port 260 is sealed by the sealant to form a closed retaining wall 250. In this way, through the bonding method 100, the lens group 200 can be formed.

The lens group 200 includes a first lens 210, a second lens 230, a barrier 250 and a transparent glue layer 270. The first lens 210 has a concave curved surface 220. The second lens 230 has a convex curved surface 240. The convex curved surface 240 is attached to the concave curved surface 220. The retaining wall 250 is located between the concave curved surface 220 and the convex curved surface 240. The retaining wall 250 is set to be located at the edge of the concave curved surface 220 and the convex curved surface 240, and the injection port 260 is sealed by a sealing glue. 250 forms a closed loop. The glue injection space formed by the concave curved surface 220, the convex curved surface 240 and the retaining wall 250, and the transparent glue layer 270 is filled in the glue injection space. In addition, due to the active alignment, the first lens 210 and the second lens 230 respectively have a first optical axis and a second optical axis, and the second optical axis has also been aligned with the first optical axis.

In some embodiments, the material of the first lens 210 or the second lens 230 may include glass or transparent plastic. The transparent plastic is, for example, polymethyl methacrylate (PMMA, or acrylic), polyethylene terephthalate (PET), or polycarbonate (PC). In some embodiments, regarding the retaining wall 250 formed by the sealant, the material of the retaining wall 250 includes acrylic material or silicone. The material of the retaining wall 250 can be UV glue and thermosetting glue. The material of the transparent glue layer 270 is liquid optical transparent glue, and the material of the transparent glue layer 270 is different from the material of the retaining wall 250.

In addition to the lens assembly 200, the vacuum injection method described in the above steps 140 and 150 can also be used for bonding other curved modules. For example, the bonding method for bonding a first element with a concave curved surface and a second element with a convex curved surface may include the following steps. Coat the sealant on the edge of one of the concave curved surface and the convex curved surface. The concave curved surface and the convex curved surface are bonded by the frame glue, so that the first element and the second element form a curved surface module. The sealant is cured to form a retaining wall, wherein the concave curved surface, the convex curved surface and the retaining wall of the lens group form a glue injection space with an injection port. Provide a sealable chamber. A tank is provided in the chamber, and the tank contains liquid transparent optical glue. Place the curved module into the chamber. Seal and evacuate the chamber. Dip the injection port of the curved module into the liquid optical transparent glue. Break the vacuum and inject the liquid transparent optical glue into the glue injection space. Curing liquid transparent optical glue. Seal the injection port of the retaining wall with a sealing glue. Similar to the aforementioned bonding method for the lens set 200, only the first element and the second element of the curved module are required to withstand the vacuum environment and break the vacuum Make sure that there is only one inlet for the injection port. In order to allow the liquid transparent optical glue to fill as large as possible between the concave and convex surfaces, the length of the injection port should be less than one-fourth of the total length of the retaining wall.

In summary, the bonding method of the present disclosure may include a two-stage bonding step. You can perform the active alignment between the lenses first, and after confirming the optical phase characteristics between the lenses, the first step is to use the sealant to do the first step. After the first step of bonding between the lenses, the sealant is used as a retaining wall, and liquid optical transparent glue can be injected between the two lenses by vacuum to complete the bonding. The use of liquid optical transparent glue improves the uniformity of bonding pressure. By vacuum injection, the amount of liquid optical transparent glue used can be changed according to different active alignment results, avoiding the problem of excessive or insufficient glue, and avoiding the generation of mixed bubbles and avoiding the effect of active alignment.

The features of several embodiments are described above so that those skilled in the art can better understand the description in various aspects. Those skilled in the art should understand that they can easily use this description as a basis to design or modify other processes and structures to achieve the same purposes or advantages as the embodiments introduced herein. Those skilled in the art should also understand that such an equivalent structure does not depart from the common spirit and scope of this description, and various changes, substitutions or alterations can be made without departing from the spirit and scope of this description.

100: method

110-160: steps

Claims (6)

A bonding method for bonding a first lens and a second lens, wherein the first lens has a concave curved surface, and the second lens has a convex curved surface. The bonding method includes: applying a concave curved surface to the convex curved surface. Coat the edge of one of the curved surfaces with a frame glue; actively align the first lens and the second lens, and bond the concave curved surface of the first lens and the convex curved surface of the second lens through the frame glue to form A lens set; curing the frame glue to form a retaining wall, wherein the concave curved surface, the convex curved surface and the retaining wall of the lens set form a glue injection space with an injection port; inject a liquid into the glue injection space Transparent optical glue; curing the liquid transparent optics to form a transparent glue layer in the glue injection space; and sealing the injection port of the retaining wall by sealing glue. The bonding method according to claim 1, wherein the step of actively aligning the first lens and the second lens further comprises: loading and fixing the first lens; loading the second lens; and moving the second lens To an alignment position so that a first optical axis of the first lens is aligned with a second optical axis of the second lens. The bonding method according to claim 1, wherein the step of injecting a liquid transparent optical glue into the glue injection space further comprises: providing a sealable cavity, in which a groove is disposed, and the groove contains Receive a liquid transparent optical glue; place the lens group that has completed the active alignment into the chamber; seal and evacuate the chamber; immerse the injection port of the lens group into the liquid optical transparent glue; and break the vacuum to make The liquid transparent optical glue is injected into the glue injection space. The bonding method according to claim 1, wherein before the step of sealing the injection port of the retaining wall with a sealant, it further comprises: filling the transparent adhesive layer through the injection port by means of glue. The fitting method according to claim 1, wherein the length of the injection port is less than a quarter of the total length of the retaining wall. The fitting method according to claim 1, wherein the area of the concave curved surface is the same as the area of the convex curved surface.

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