TWI447464B - Lens module and assembling method for the same - Google Patents

Description

Lens and its assembly method

The present invention relates to the field of optical systems, and more particularly to a lens and an assembly method thereof.

With the development of camera technology, the lens has been widely used in various types of camera devices, and the combination of the lens and various portable electronic devices such as mobile phones and computers has been favored by many consumers. The quality of the lens directly affects the display quality of optical modules and even digital image products. The Modulation Transfer Function (MTF) value is a parameter used to comprehensively evaluate the sharpness, contrast, and resolution of the lens. In the optical industry, the value of MTF is between 0 and 1 (0% to 100%). Generally, the higher the MTF value (for example, 90%), the more representative the more subtle changes in the image to be measured. For details, please refer to Klomp enhouwer, M.A., 2005, Image Processing, 2005. ICIP 2005. IEEE International Conference on Volume 2, Introduction to The temporal MTF of displays and related video signal processing. After the lens is assembled, it is usually tested to screen and eliminate lenses with MTF values below the specified value.

In order to capture a high-quality image of the lens, two or more lenses are usually accommodated in the lens barrel, and the adjacent two lenses are separated by a spacer ring. Taking a lens with two lenses as an example, in the lens assembly process, the first lens is first sucked into the lens barrel by a vacuum nozzle, and the position is fixed by a pressure bar to fix the position; Putting the spacer ring into the lens barrel; finally, the second lens is taken into the lens barrel, and the eccentricity between the lens and the first lens is adjusted by the pressure bar to fix the glue. The assembly process is complicated, and the MTF values of the lenses assembled by this method are not all satisfactory.

In view of this, it is necessary to provide a lens that is easy to assemble and has a high assembly yield and an assembly method thereof.

A lens includes a lens barrel, a first lens, and a second lens. The lens barrel has a receiving cavity. The first lens is received in the receiving cavity and close to the object side of the lens. The first lens includes a first optical portion for optical imaging and a first fixed portion that surrounds the first optical portion. The first fixing portion has a plurality of first openings. The second lens is also received in the receiving cavity and close to the image side of the lens. The second lens includes a second optical portion for optical imaging and a second fixed portion for circumferentially connecting the second optical portion. The second optical portion is optically coupled to the first optical portion. The second fixing portion is correspondingly engaged with the first fixing portion, and has a plurality of second openings corresponding to the first opening in a one-to-one manner, so that the plurality of first openings are respectively exposed in the plurality of second openings.

A lens assembly method comprising the steps of: providing a lens as described above; placing a first lens and a second lens in a receiving cavity of the lens barrel in sequence, and bringing the first lens closer to an object side of the lens, the second lens Adjacent to the image side of the lens; adjusting the position of the first lens by a plurality of first openings exposed to the plurality of second openings; adjusting the position of the second lens by the plurality of second openings.

The first opening of the lens of the technical solution is completely exposed to the second opening, so that after the first lens and the second lens are both placed into the lens during assembly, the first lens close to the object side of the lens can also be adjusted by the fixture. The location allows for a simplified assembly process. The technical side The lens assembly method fixes the second lens after the lens performance test is passed, so that the subsequent test steps can be omitted, and the yield of the obtained lens is as high as 100%.

10, 20‧‧‧ lens

11, 21‧‧ ‧ lens barrel

12, 22‧‧‧ first lens

13, 23‧‧‧ spacer ring

14, 24‧‧‧ second lens

110‧‧‧ side wall

111, 211‧‧‧ bottom wall

112, 212‧‧‧ inner surface

113‧‧‧ outer surface

114‧‧‧ containment chamber

115‧‧‧ external thread

116‧‧‧ aperture hole

120, 220‧‧‧ First Optical Department

121, 221‧‧‧ first fixed department

122‧‧‧ first surface

123, 223‧‧‧ second surface

124, 224‧‧‧ first connection surface

125, 225‧‧‧ first opening

126, 226‧‧‧ first side wall

227‧‧‧ second side wall

θ 1‧‧‧first central angle

130‧‧‧ inside side

131‧‧‧Outside

132‧‧‧Light hole

140, 240‧‧‧Second Optics

141‧‧‧Second fixed department

142‧‧‧ third surface

143‧‧‧ fourth surface

144‧‧‧second connection surface

145, 245‧‧‧ second opening

146‧‧‧ third side wall

θ 2‧‧‧second central angle

25‧‧‧shading film

26‧‧‧ third lens

260‧‧‧ Third Optical Department

261‧‧ Third Fixed Department

262‧‧‧ fifth surface

263‧‧‧ sixth surface

1 is an exploded view of a lens provided by a first embodiment of the present technical solution.

2 is a cross-sectional view showing the assembled state of the lens provided by the first embodiment of the present technical solution.

FIG. 3 is a top plan view showing the assembled state of the lens provided by the first embodiment of the present technical solution.

4 is an exploded view of a lens provided by a second embodiment of the present technical solution.

Figure 5 is a cross-sectional view showing the assembled state of the lens provided by the second embodiment of the present technical solution.

The lens of the present technical solution and the assembly method thereof will be further described in detail below with reference to the accompanying drawings and the embodiments.

Referring to FIG. 1 to FIG. 3 , the lens 10 according to the first embodiment of the present invention includes a lens barrel 11 and a first lens 12 , a spacer ring 13 and a second lens 14 that are sequentially received in the lens barrel 11 .

The lens barrel 11 is substantially cylindrical and includes a connecting side wall 110 and a bottom wall 111. The sidewall 110 has opposing inner and outer surfaces 112, 113. The inner surface 112 encloses a receiving cavity 114. The outer surface 113 has external threads 115 for mating with the mirror mount. The bottom wall 111 is connected to one side of the side wall 110, and a diaphragm hole 116 is opened at the center thereof. The aperture hole 116 is a through hole penetrating the bottom wall 111 for the imaging light to enter the lens barrel 11.

The first lens 12 is received in the receiving cavity 114 and close to the object side of the lens 10 . The first lens 12 includes a first optical portion 120 for optical imaging and surround The first fixing portion 121 of the first optical portion 120 is connected. The first optical portion 120 may be spherical or aspherical. The first fixing portion 121 has a first surface 122 , a second surface 123 , and a first connecting surface 124 . The first surface 122 is adjacent to the object side of the lens and opposite to the bottom wall 111. In this embodiment, the first surface 122 is in contact with the bottom wall 111. The second surface 123 is opposite the first surface 122. The first connecting surface 124 is connected between the first surface 122 and the second surface 123. The first fixing portion 121 further has a plurality of first openings 125. In this embodiment, the number of the plurality of first openings 125 is four, and is equiangularly distributed around the central axis of the first lens 12. Each of the first openings 125 opens from the first connecting surface 124 toward the central axis of the first lens 12 and penetrates the second surface 123 . The first opening 125 can be a blind slot or a through slot. Each of the first openings 125 has a first sidewall 126 located near a central axis of the first lens 12. In this embodiment, the first sidewall 126 is parallel to the first connecting surface 124. Each of the first openings 125 corresponds to a first central angle at the center of the first lens 12, which is θ 1 .

The spacer ring 13 is a circular ring located on the object side of the first lens 12 opposite to and away from the lens 10. Specifically, the spacer ring 13 is in contact with the second surface 123 of the first fixing portion 121. The spacer ring 13 has a coaxial inner side surface 130 and an outer side surface 131 . The inner side surface 130 encloses a light transmission hole 132 , and the light transmission hole 132 corresponds to the first optical portion 120 . The outer side surface 131 is located on one side of the first opening 125 close to the central axis of the first lens 12, that is, the spacer ring 13 does not cover the first opening 125.

The second lens 14 is also housed in the receiving cavity 114 and close to the image side of the lens 10. The second lens 14 includes a second optical portion 140 for optical imaging and a second fixing portion 141 that surrounds the second optical portion 140. The second optical portion 140 is optically coupled to the first optic portion 120, which may also be spherical or aspherical. The second fixing portion 141 is matched with the first fixing portion 121 and has a third surface 142 , a fourth surface 143 and a second connecting surface 144 . The third surface 142 is adjacent to the object side of the lens and is in contact with the spacer ring 13. The fourth surface 143 is opposite the third surface 142. The second connecting surface 144 is connected between the third surface 142 and the fourth surface 143. The second fixing portion 141 further has a plurality of second openings 145. In this embodiment, corresponding to the plurality of first openings 125, the number of the plurality of second openings 145 is also four, and is equiangularly distributed around the central axis of the second lens 14. Each of the second openings 145 is a through groove extending from the third surface 142 toward the fourth surface 143 and has a third sidewall 146 parallel to the second connecting surface 144 . In this embodiment, the second opening 145 has an arc shape, and each of the second openings 145 corresponds to a second central angle at the center of the second lens 14 of θ 2 . The third sidewall 146 is located on a side of the first sidewall 126 adjacent to a central axis of the first lens 12, and the second central angle θ 2 is greater than the first central angle θ 1 such that each second opening 145 When the first opening 125 is placed corresponding to the first opening 125, the first opening 125 is completely exposed to the second opening 145, as shown in FIG.

The technical solution also provides a method for assembling the lens 10 as described in the above item, which may include the following steps:

In the first step, the lens 10 as described above is provided.

In this embodiment, in addition to providing the lens barrel 11, the first lens 12 and the second lens 14, a spacer ring 13 and a first jig and a second for assembling the first lens 12 and the second lens 14 respectively are further provided. Fixture. The front end of the first jig corresponds to the shape of the first opening 125, and the front end of the second jig also corresponds to the shape of the second opening 145 so as to cooperate with the first lens 12 and the second lens 14 and be assembled. .

In the second step, the first lens 12 and the second lens 14 are sequentially placed in the receiving cavity 114 of the lens barrel 11 , and the first lens 12 is close to the object side of the lens 10 , and the second lens 14 is close to the image of the lens 10 . side. Of course, it is also necessary to place the spacer ring 13 between the first lens 12 and the second lens 14.

In the third step, the position of the first lens 12 is adjusted by the plurality of first openings 125 exposed to the plurality of second openings 145. Specifically, the first jig can pass through the second opening 14 and cooperate with the first opening 125 of the first lens 12 to perform adjustment, and the first lens 12 is glued and fixed after the adjustment is completed.

In the fourth step, the position of the second lens 14 is adjusted by the plurality of second openings 145.

Specifically, the performance of the lens 10 is simultaneously tested during the adjustment process. The performance test is the MTF test. When the test is performed, the image sensor of the test instrument is used to cooperate with the lens 10 to be tested for imaging, and the image quality is analyzed to obtain the MTF value of the lens 10. If the measured MTF value does not reach the specified value, the position of the second lens 14 needs to be adjusted, and then tested until the measured MTF value reaches the prescribed range, and the second lens 14 is dispensed.

The first opening 125 of the lens 10 of the present technical solution is completely exposed to the second opening 145, so that when the first lens 12 and the second lens 14 are both placed into the lens during assembly, the lens can be adjusted by the fixture. The position of the first lens 12 on the side, thereby simplifying the assembly process. The assembly method of the technical solution fixes the second lens 14 after the lens performance test is passed, so that the subsequent test steps can be omitted, and the yield of the obtained lens 10 is as high as 100%.

Referring to FIG. 4 and FIG. 5 together, the lens 20 provided by the second embodiment of the present invention is substantially the same as the lens 10 of the first embodiment, except that the first opening 22 and the second opening 225 of the first lens 22 are provided. The number of second openings 245 on the lens 24 is two, and the number of rings They are equally angular around their respective central axes. The first optical portion 220 of the first lens 22 protrudes toward the image side of the lens 10, and the first opening 225 has a first sidewall 226 and a second sidewall 227 connected thereto. The first sidewall 226 and the second sidewall 227 are both connected to the first connecting surface 224. The lens 20 of the present embodiment further includes a light shielding sheet 25 and a third lens 26.

The light shielding sheet 25 is also annular, and is located on one side of the first lens 22 near the lens object side. Specifically, the light shielding sheet 25 is in contact with the second surface 223 of the first fixing portion 221 .

The third lens 26 is located on one side of the light shielding sheet 25 near the lens object side. The third lens 26 includes a third optical portion 260 for optical imaging and a third fixed portion 261 that surrounds the third optical portion 260. The third optical portion 260 is optically coupled to the second optical portion 240 and the first optical portion 220, and may be spherical or aspherical. The third fixing portion 261 has a fifth surface 262 and a sixth surface 263 opposite to each other. The fifth surface 262 is located near one side of the light shielding sheet 25, and the sixth surface 263 is close to the object side of the lens and is in contact with the bottom wall 211.

The assembling method of the lens 20 of the present embodiment is substantially the same as the assembling method of the lens 10 of the first embodiment, except that the third lens 26 and the light shielding sheet 25 are first placed in the lens barrel 21 in order to make the third lens 26 The inner surface 212 of the lens barrel 21 is interposed, and the third lens 26 and the light shielding sheet 25 are fixed, and then the first lens 22, the spacer ring 23 and the second lens 24 are sequentially placed in the lens barrel 21. Moreover, when adjusting the position of the first lens 22, it is necessary to consider the eccentricity between it and the third lens 26.

Of course, the number of the first opening and the second opening is not limited to two or four, and may be three or more. And the number of the first opening and the second opening are not necessarily equal, and the distribution manner thereof does not necessarily have to be equiangular around the respective central axes. cloth. The shape of the cross section of the first opening and the second opening is not limited to being curved or triangular, and may be other shapes that facilitate fitting with the jig for assembly. The first opening and the second opening do not necessarily have to penetrate the first connecting surface and the second connecting surface.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

10‧‧‧ lens

11‧‧‧Mirror tube

12‧‧‧ first lens

13‧‧‧ spacer ring

14‧‧‧second lens

110‧‧‧ side wall

111‧‧‧ bottom wall

112‧‧‧ inner surface

113‧‧‧ outer surface

114‧‧‧ containment chamber

115‧‧‧ external thread

120‧‧‧First Optics

121‧‧‧First Fixed Department

122‧‧‧ first surface

123‧‧‧ second surface

124‧‧‧ first connection surface

125‧‧‧ first opening

126‧‧‧First side wall

θ 1‧‧‧first central angle

130‧‧‧ inside side

131‧‧‧Outside

132‧‧‧Light hole

140‧‧‧Second Optics

141‧‧‧Second fixed department

142‧‧‧ third surface

143‧‧‧ fourth surface

144‧‧‧second connection surface

145‧‧‧second opening

146‧‧‧ third side wall

θ 2‧‧‧second central angle

Claims (9)

A lens comprising: a lens barrel having a receiving cavity; a first lens received in the receiving cavity and adjacent to an object side of the lens, the first lens comprising a first optical part for optical imaging a first fixing portion having a first optical portion connected to the first optical portion, wherein the first fixing portion has a plurality of first openings; and a second lens that is also received in the receiving cavity and adjacent to an image side of the lens, The second lens includes a second optical portion for optical imaging and a second fixed portion surrounding the second optical portion, the second optical portion being optically coupled to the first optical portion, the second fixed portion and Correspondingly, the first fixing portion has a plurality of second openings corresponding to the first opening, so that the plurality of first openings are respectively exposed in the plurality of second openings, and each of the first openings corresponds to the first lens The first central angle of the center is less than a second central angle of each second opening corresponding to the center of the second lens. The lens of claim 1, wherein the plurality of first openings are equiangularly distributed around a central axis of the first lens. The lens of claim 1, wherein the first fixing portion has an opposite first surface and a second surface, the first surface is adjacent to an object side of the lens, and the second surface is adjacent to the second surface a lens, each of the first openings is a blind groove or a through groove extending from the second surface toward the first surface, the second fixing portion has a third surface and a fourth surface, the third surface is adjacent to the first lens The fourth surface is opposite to the third surface, and each of the second openings is a through groove extending from the third surface toward the fourth surface. The lens of claim 3, wherein the first fixing portion further has a first connecting surface connected between the first surface and the second surface, and the second fixing portion further has a connection a second connecting surface between the third surface and the fourth surface, each of the first openings extends through the first connecting surface, and each of the second openings extends through the second connecting surface. The lens of claim 4, wherein each of the first openings has a first side wall parallel to the first connecting surface, and each of the second openings has a third side wall parallel to the second connecting surface, The third sidewall is located on a side of the first sidewall adjacent to a central axis of the lens barrel. The lens of claim 4, wherein each of the first openings has a first side wall and a second side wall, and at least one of the first side wall and the second side wall is The connection faces are connected. The lens of claim 1, further comprising a spacer ring disposed between the first lens and the second lens, the spacer ring having opposite inner and outer sides, the inner side Enclosing a light-transmissive hole corresponding to the first optical portion and the second optical portion, the outer surface being located on a side of the first opening adjacent to a central axis of the first lens. The lens of claim 1, further comprising a third lens and a light shielding film received in the receiving cavity, wherein the first lens is disposed between the second lens and the third lens, The light shielding sheet is disposed between the first lens and the third lens. A method for assembling a lens, comprising the steps of: providing a lens according to claim 1; placing the first lens and the second lens sequentially in a receiving cavity of the lens barrel, and bringing the first lens closer to the object side of the lens The second lens is adjacent to the image side of the lens; the position of the first lens is adjusted by the plurality of first openings exposed in the plurality of second openings; and the position of the second lens is adjusted by the plurality of second openings.