Optical lens and manufacturing method thereof

Abstract

The present invention can provide an optical lens in which a lens part having a light incident / exit surface as an optical effective part and a lens edge part having a surface other than the light incident / exit surface as a non-optical effective part are integrally molded. Wherein the lens edge portion has a non-transparent portion in a part or all thereof, the lens edge portion wraps the entire outer periphery of the lens portion, and the lens portion and the lens edge portion contain the same thermoplastic resin. When the optical lens is assembled into an optical lens unit, light leakage and resolution characteristics in the lens barrel frame can be improved. Moreover, when the optical lens of the present invention is used as a lens for a smartphone, halo and ghosting can be suppressed and a clear image can be obtained due to improved light reflection resistance and light blocking properties. Moreover, since the lens part and the lens edge part are integrally molded, the optical lens unit can be miniaturized, the use of a conventional spacer is not required, the manufacturing cost can be reduced, and the degree of freedom of the design of the optical lens unit can be increased.

Description

Technical Field

[0001] The present invention relates to an optical lens that enables the thinning and miniaturization of the optical lens unit and reduces light leakage caused by reflected light from the interface, a method for manufacturing the same, and an optical lens unit comprising the optical lens.

[0002] This case is a divisional application of application number 201980084937.2 (PCT / JP2019 / 050451), filed on December 24, 2019, entitled "Optical Lens and Method for Manufacturing the Same". Background Technology

[0003] With the miniaturization, thinning, and popularization of portable devices, there is a growing demand for further miniaturization and thinning of the optical lens units mounted on them, as well as high productivity.

[0004] In the past, spacers were inserted between lenses to prevent reflection and block light (Patent Document 1). However, when there is a difference in refractive index between the lens and the spacer, surface reflection occurs, and the reflected light becomes the cause of light leakage.

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2018-146878 Summary of the Invention

[0006] The technical problem that the invention aims to solve The technical problem to be solved by the present invention is to provide an optical lens that can achieve thinning and miniaturization of the optical lens unit and reduce light leakage caused by reflection of light from the interface.

[0007] Technical solutions for solving technical problems The inventors of this invention conducted in-depth research and discovered that by setting specific non-transparent portions at the edge of the optical lens, the aforementioned technical problems can be solved.

[0008] That is, the present invention is as follows.

[0009] <1> An optical lens, wherein the optical lens is integrally formed from a lens portion having a light incident and exiting surface as an optically effective part, and a lens edge portion having a surface other than the light incident and exiting surface as a non-optically effective part, wherein, The aforementioned lens has a non-transparent portion in part or all of its edge. The lens portion and the lens edge portion described above contain thermoplastic resin. The non-transparent portion of the lens edge also contains one or more of a black dye and a black pigment, totaling 0.1 to 5% by mass.

[0010] <2> The optical lens described in <1> above, wherein the thermoplastic resin contained in the lens portion contains at least one of the structural units shown in the following formula (1), the following structural units shown in the following formula (2), the following structural units shown in the following formula (3), the following structural units shown in the following formula (4) and the following structural units shown in the following formula (5). (In formula (1), R1 and R2 independently represent hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group with 1 to 6 carbon atoms, aryl group with 6 to 20 carbon atoms that may contain heterocyclic atoms selected from O, N and S, alkenyl group with 2 to 6 carbon atoms, alkoxy group with 1 to 6 carbon atoms, or aralkyl group with 7 to 17 carbon atoms, respectively.) a and b independently represent integers from 0 to 5. In formula (2), R3 to R6 independently represent hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group with 1 to 6 carbon atoms, aryl group with 6 to 20 carbon atoms that may contain heterocyclic atoms selected from O, N and S, alkenyl group with 2 to 6 carbon atoms, alkoxy group with 1 to 6 carbon atoms, or aralkyl group with 7 to 17 carbon atoms. c and d independently represent integers from 0 to 6, and e and f independently represent integers from 0 to 4. (In formula (3), R7~R 10 Each of the following can be independently represented: a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 20 carbon atoms that may contain heterocyclic atoms selected from O, N, and S, an alkenyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aralkyl group having 7 to 17 carbon atoms. g to j represent integers from 0 to 4 independently. (In formula (4), R represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.) (In formula (5), A represents an alkylene group with 1 to 5 carbon atoms, p represents 0 or 1, K1 represents a hydrogen atom or an alkyl group with 1 to 5 carbon atoms, K2 represents a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, or an aryl group with 6 to 20 carbon atoms, Z represents a carboxyl group, an alkoxycarbonyl group, a cycloalkoxycarbonyl group, an aryloxycarbonyl group, a hydroxyalkylcarbonyl group, a glycidyloxycarbonyl group, a cyano group, or an amide group, and q represents 0 or 1.) <3> The optical lens described in <2> above, wherein the thermoplastic resin contained in the lens portion includes all the structural units shown in formula (1), formula (2), and formula (3).

[0011] <4> An optical lens as described in any one of <1> to <3> above, wherein the lens portion and the lens edge portion contain the same resin.

[0012] <5> An optical lens, comprising a lens portion having a light incident and exiting surface as an optically effective part, and a lens edge portion having a surface other than the light incident and exiting surface as a non-optically effective part. The aforementioned lens has a non-transparent portion in part or all of its edge. The non-transparent portion of the lens edge is either a portion formed by coating the lens edge with a black material or a portion formed by carbonizing the lens edge.

[0013] <6> An optical lens as described in any one of <1> to <5> above is used in a smartphone.

[0014] <7> An optical lens unit comprising any one of <1> to <6> above.

[0015] <8> The optical lens unit described in <7> above does not contain a spacer.

[0016] <9> A method for manufacturing an optical lens, used to manufacture the optical lens described in any one of <1> to <4> above, wherein, The lens portion and the lens edge portion are integrally formed using two molding methods: insert molding and two-color molding.

[0017] The effects of the invention The optical lens of the present invention, which integrally molds the lens portion and the lens edge portion and has a specific non-transparent area at the lens edge portion, improves light leakage and resolution characteristics within the barrel frame when assembling an optical lens unit. Furthermore, when the optical lens of the preferred embodiment of the present invention is used as a lens for a smartphone, it improves anti-reflective and light-shielding properties, suppresses halos and ghosting, and enables the acquisition of clear images.

[0018] Furthermore, by molding the lens section and the lens edge section as a single unit, the optical lens unit can be miniaturized, eliminating the need for conventional spacers. This reduces manufacturing costs and increases the design freedom of the optical lens unit. In particular, when the same resin is used for both the lens section and the lens edge section, light leakage and resolution characteristics within the lens barrel are further improved, and anti-reflective effects and diffuse reflection are suppressed. Attached Figure Description

[0019] Figure 1 This is a schematic cross-sectional view showing the first embodiment of the optical lens of the present invention.

[0020] Figure 2 This is a schematic cross-sectional view showing a second embodiment of the optical lens of the present invention.

[0021] Figure 3 This is a schematic cross-sectional view showing a third embodiment of the optical lens of the present invention.

[0022] Figure 4 This is a schematic cross-sectional view showing the fourth embodiment of the optical lens of the present invention.

[0023] Figure 5 This is a schematic cross-sectional view showing the fifth embodiment of the optical lens of the present invention.

[0024] Figure 6 This is a schematic cross-sectional view showing the sixth embodiment of the optical lens of the present invention.

[0025] Symbol Explanation 1…lens portion; 2…lens edge portion (with all parts being non-transparent); 2'…lens edge portion (with a portion being non-transparent); 10, 20, 30, 40, 50, 60…optical lens. Detailed Implementation

[0026] Hereinafter, preferred embodiments of the optical lens of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, in the first to sixth embodiments, the same or equivalent constituent parts are labeled with the same reference numerals.

[0027] [First Implementation] like Figure 1As shown, the optical lens 10 is suitable for use in cameras such as smartphones, differential scanning calorimetry (DSC), and automotive lenses. It is small in size with a diameter of approximately 1.0 to 20.0 mm, and further miniaturization and higher precision are required. The diameter is preferably 1.0 to 10.0 mm, more preferably 3.0 to 10.0 mm. This optical lens 10 is integrally formed by insert molding of the lens portion 1, which is the optically effective part and has a light incident and exit surface, and the lens edge portion 2, which is the non-optically effective part and has a surface other than the light incident and exit surface. "Integral molding" means that the product is integrally formed during the bonding with the component without the use of secondary bonding or mechanical joining.

[0028] The optical lens 10 according to the first embodiment is such that the lens edge portion 2 is entirely opaque. An opaque portion simply means a part that is not transparent. In the first embodiment, to provide the opaque portion, the lens portion 1 and the lens edge portion 2 contain a thermoplastic resin, and the opaque portion of the lens edge portion 2 also contains one or more of a black dye and a black pigment, totaling 0.1 to 5% by mass. The total content of one or more of the black dye and black pigment is preferably 0.5 to 3% by mass, more preferably 0.5 to 2% by mass.

[0029] Specific examples of black dyes include Sumitomo Chemtex's SumiplastBlack G-2, Sumiplast Black H3B, Sumiplast Black HLG, and Sumiplast Black HB; Chuo Synthetic Chemical Co., Ltd.'s Black S, Black SF, Black 109, and Black 141; ORIENT Chemical Industries Co., Ltd.'s VALIFAST BLACK 1815, VALIFAST BLACK 1821, OIL BLACK 860, NUBIAN BLACK PC-5857, 5877, 5856, NUBIAN BLACK PC-0855, NUBIAN BLACK NH-805, 815, NUBIAN BLACK TN-870, 877, and 807; and Arimoto Chemical Co., Ltd.'s Plast Black 8950-N, Plast Black 8970, and Oil Black DA-411.

[0030] Specific examples of black pigments include, for instance, NUBIANGREY IR-B and OPLAS BLACK 838 manufactured by ORIENT Chemical Industries, Ltd.; carbon black, especially carbon black with an arithmetic mean diameter of 5 to 60 nm (preferably 10 to 50 nm) obtained by observing carbon black particles under an electron microscope (e.g., SEAST and Aqua Black manufactured by Tokai Carbon Co., Ltd.; BLACK PEARLS, ELFTEX, VULCAN, MOGUL, MONARCH, EMPORER, REGAL, UNITED, SPHERON, STERLING, SHOBLACK, etc. manufactured by Cabot Corporation; HCF, MCF, RCF, LFF, and SCF series manufactured by Mitsubishi Chemical Corporation; NIPPON STEEL Carbon Co., Ltd., NITERON, HTC, etc.).

[0031] In this invention, both black dye (organic) and black pigment (inorganic) can be used. They can be added and mixed directly, or they can be used as masterbatches to produce high-concentration products (e.g., about 50%) and mixed together.

[0032] As an example of the manufacturing method of the optical lens 10 according to the first embodiment, resin for the lens portion 1 and resin for the lens edge portion 2 are prepared. A predetermined amount of one or more of a black dye and a black pigment is added to the resin for the lens edge portion 2, and the mixture is melt-mixed to prepare a black resin. Next, the lens portion 1 and the lens edge portion 2 are integrally molded using two molding methods: insert molding and two-color molding. The optical lens 10 completed by integral molding includes non-transparent portions throughout the lens edge portion 2.

[0033] The lens portion of the optical lens of the present invention contains a thermoplastic resin, wherein the thermoplastic resin contains at least one of the structural units shown in formula (1), formula (2), formula (3), formula (4), and formula (5) below, and is therefore preferred because it satisfies the performance of an optical lens such as refractive index, Abbe number, and Tg. In formula (1), R1 and R2 independently represent hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group with 1 to 6 carbon atoms, or aryl group with 6 to 20 carbon atoms, alkenyl group with 2 to 6 carbon atoms, alkoxy group with 1 to 6 carbon atoms, or aralkyl group with 7 to 17 carbon atoms, which may contain heterocyclic atoms selected from O, N and S. Preferably, they independently represent hydrogen atom, phenyl, naphthyl and substituent selected from the following. Among them, hydrogen atoms are preferred. .

[0034] a and b can each independently represent integers from 0 to 5, preferably 0 or 1 respectively. In formula (2), R3 to R6 independently represent hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group with 1 to 6 carbon atoms, or aryl group with 6 to 20 carbon atoms, alkenyl group with 2 to 6 carbon atoms, alkoxy group with 1 to 6 carbon atoms, or aralkyl group with 7 to 17 carbon atoms, which may contain heterocyclic atoms selected from O, N and S. Preferably, they independently represent hydrogen atom, phenyl, naphthyl and substituents selected from the following. Among them, hydrogen atoms are preferred. .

[0035] c and d each independently represent an integer from 0 to 6, preferably representing 0 or 1 respectively. e and f each independently represent an integer from 0 to 4, preferably representing 0 or 1 respectively. In equation (3), R7~R 10 Each of the following can be independently represented: hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group having 1 to 6 carbon atoms, or aryl group having 6 to 20 carbon atoms, alkenyl group having 2 to 6 carbon atoms, alkoxy group having 1 to 6 carbon atoms, or aralkyl group having 7 to 17 carbon atoms, which may contain heterocyclic atoms selected from O, N and S. Preferably, each of the following can be independently represented: hydrogen atom, phenyl group, naphthyl group and substituent selected from the following. Among them, hydrogen atoms are preferred. .

[0036] g to j represent integers from 0 to 4 independently, preferably representing 0 or 1 independently. In formula (4), R represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, preferably a hydrogen atom. In formula (5), A represents an alkylene group with 1 to 5 carbon atoms, p represents 0 or 1, K1 represents a hydrogen atom or an alkyl group with 1 to 5 carbon atoms, K2 represents a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, or an aryl group with 6 to 20 carbon atoms, Z represents a carboxyl group, an alkoxycarbonyl group, a cycloalkoxycarbonyl group, an aryloxycarbonyl group, a hydroxyalkylcarbonyl group, a glycidyloxycarbonyl group, a cyano group, or an amide group, and q represents 0 or 1. K2 preferably represents a hydrogen atom.

[0037] The thermoplastic resin contained in the lens portion of the optical lens of the present invention preferably includes any one of the structural units shown in formula (1), formula (2), formula (3), and formula (4) above. Furthermore, when the thermoplastic resin contained in the lens portion of the optical lens of the present invention includes all of the structural units shown in formula (1), formula (2), and formula (3) above, it is preferable because the optical properties such as refractive index are excellent.

[0038] Furthermore, when the lens portion and the lens edge portion of the optical lens of the present invention contain the same resin, the reflectivity can be made the same, and as a result, the light leakage characteristics and reflection characteristics become good, which is therefore preferred.

[0039] [Second Implementation] like Figure 2 As shown, the optical lens 20 of the second embodiment is the same as the optical lens 10 of the first embodiment, except that a portion of the lens edge 2' has a non-transparent part. The diagonal portion in the lens edge 2' of the optical lens 20 is a non-transparent part, but the proportion of the non-transparent part in the lens edge 2' is not particularly limited and can be adjusted appropriately.

[0040] [Third Implementation] like Figure 3 As shown, the optical lens 30 of the third embodiment is the same as the optical lens 20 of the second embodiment, except that the shape of the non-transparent portion in the lens edge portion 2' is different. The diagonal portion in the lens edge portion 2' of the optical lens 30 is a non-transparent portion, but the shape of this non-transparent portion is not particularly limited and can be appropriately changed.

[0041] [Fourth Implementation] like Figure 4 As shown, the optical lens 40 of the fourth embodiment is the same as the optical lens 30 of the third embodiment, except that the shape of the non-transparent portion in the lens edge portion 2' is different. The diagonal portion in the lens edge portion 2' of the optical lens 40 is a non-transparent portion, but the shape of this non-transparent portion is not particularly limited and can be appropriately changed.

[0042] [Fifth Implementation] like Figure 5 As shown, the optical lens 50 of the fifth embodiment is as follows: it has a lens portion 1 having a light incident and exit surface as an optically effective part, and a lens edge portion 2' having a surface other than the light incident and exit surface as a non-optically effective part. The lens edge portion 2' has a non-transparent portion in a part thereto, which is formed by covering the lens edge portion 2' with a black material.

[0043] The optical lens 50 of the fifth embodiment differs from the optical lenses of the first to fourth embodiments in that it does not require the lens portion and the lens edge portion to be integrally formed.

[0044] As for the aforementioned black material, there are no particular restrictions as long as it can be evenly coated on the edge of the lens. Commercially available inks, black paints, and black dyes can be used, such as NUBIAN BLACK PC-8550 manufactured by ORIENT Chemical Industry Co., Ltd., which is a jet-black dye.

[0045] Methods for applying the aforementioned black material include coating, spraying, and impregnating the black material.

[0046] The resin used in the lens portion 1 of the optical lens 50 is not particularly limited, and the resin described in the optical lens 10 of the first embodiment can preferably be used.

[0047] [Sixth Implementation Method] like Figure 6 As shown, the optical lens 60 of the sixth embodiment is the same as the optical lens 50 of the fifth embodiment, except that the non-transparent part in the lens edge 2' is formed by carbonizing the lens edge 2'.

[0048] Methods for carbonizing the lens edge 2' of the optical lens 60 include methods such as heating, combustion to form carbides, using strong dehydration reactions such as sulfuric acid, and laser irradiation.

[0049] [Optical Lens Unit] The optical lens unit of the present invention includes the optical lens of the present invention described above. The optical lens unit of the present invention does not require a spacer, thus enabling thinning and miniaturization, and reducing light leakage caused by reflections from the interface.

[0050] As an example of the manufacturing method of the optical lens unit of the present invention, an optical lens unit can be manufactured by overlapping four optical lenses of the present invention and placing them into an optical lens barrel.

[0051] Example The present invention will now be specifically described through embodiments, but the present invention is not limited to any of the following embodiments. The characteristics of the obtained optical lens will be evaluated as follows.

[0052] <Light Leakage Characteristics> Light leakage within the microscope tube is evaluated visually. A score of A is given for no light leakage, B for almost no light leakage, C for some light leakage, and D for significant light leakage. A and B are considered acceptable levels.

[0053] <Resolution Characteristics> Overlap the four obtained optical lenses and place them into an optical lens barrel to fabricate an optical lens unit. Evaluate visually: A is rated as no blurring of the projected text, B as almost no blurring, C as some blurring, and D as significant blurring. A and B are considered acceptable levels.

[0054] (Example 1) Prepare resin A and resin B as described below.

[0055] <Preparation of Resin A> As raw materials, 8.0 kg (14.85 mol) of 9,9-bis[6-(2-hydroxyethoxy)naphthyl-2-yl]fluorene as shown in structural formula (i), 7.5 kg (20.03 mol) of 2,2'-bis(2-hydroxyethoxy)-1,1'-bidinaphthalene as shown in structural formula (ii), 7.5 kg (12.70 mol) of 9,9-bis[4-(2-hydroxyethoxy)-3-phenylphenyl]fluorene as shown in structural formula (iii), 10.5 kg (49.02 mol) of diphenyl carbonate, and 2.5 × 10 －2 16 mL of sodium bicarbonate aqueous solution (4.0 × 10⁻⁶ mol / L) －4 One mole, i.e., the total amount of the dihydroxy compound, is 8.4 × 10⁻⁶. －6The raw material (in molar form) was placed in a 50L reactor equipped with a stirrer and a distillation device and heated to 180°C under a nitrogen atmosphere of 760 mmHg. After 30 minutes of heating, complete dissolution of the raw material was confirmed, followed by stirring for 120 minutes under the same conditions. Then, the pressure was adjusted to 200 mmHg, and the temperature was increased to 200°C at a rate of 60°C / hr. At this point, the byproduct phenol was observed to begin distillation. The reaction was then carried out at 200°C for 20 minutes. The temperature was then increased to 230°C at a rate of 75°C / hr, and after 10 minutes of heating, the temperature was maintained while the pressure was reduced to below 1 mmHg over 2 hours. The temperature was then increased to 245°C at a rate of 60°C / hr, and stirring was continued for another 40 minutes. After the reaction was complete, nitrogen was introduced into the reactor to restore atmospheric pressure, and the resulting polycarbonate resin (resin A) was granulated and removed. Furthermore, the obtained resin A is a resin containing all the structural units shown in formula (1), formula (2), and formula (3) above. <Preparation of Resin B> Resin B was prepared by melt mixing 10 kg of the above-obtained resin A with 100 g of resin colorant (manufactured by ORIENT Chemical Industry Co., Ltd., trade name: NUBIAN BLACK PC-5857) used as a black dye using a twin-screw extruder.

[0056] <Fabrication of Optical Lenses and Optical Lens Units> Resin A and Resin B were heated and dried at 100°C for 3 hours respectively. Then, they were subjected to two molding processes: insertion molding with Resin A forming the lens portion and Resin B forming the lens edge portion, to obtain an optical lens. Four of the obtained optical lenses were stacked and placed into an optical lens barrel to fabricate an optical lens unit. The physical properties of the obtained optical lens unit are shown in Table 1.

[0057] (Example 2) <Preparation of Resin B-1> Resin B-1 was prepared by melt mixing 10 kg of the above-obtained resin A with 100 g of carbon black (MCF series #1000 manufactured by Mitsubishi Chemical Corporation) as a black pigment using a twin-screw extruder.

[0058] Except for replacing resin B with resin B-1, the optical lens was fabricated in the same manner as in Example 1, and then the optical lens unit was fabricated. The physical properties of the obtained optical lens unit are shown in Table 1.

[0059] (Example 3) Prepare resin C as described below.

[0060] <Preparation of Resin C> Resin C was prepared by melt mixing 10 kg of polycarbonate resin (trade name: Iupilon S-3000R) manufactured by Mitsubishi Gas Chemical Co., Ltd., and 100 g of resin colorant (manufactured by ORIENT Chemical Industry Co., Ltd., trade name: NUBIAN BLACK PC-5857) used as a black dye using a twin-screw extruder.

[0061] Except that resin B is replaced with resin C, the optical lens is fabricated in the same manner as in Example 1, and then the optical lens unit is fabricated. The physical properties of the obtained optical lens unit are shown in Table 1.

[0062] (Comparative Example 1) Except for replacing resin B with resin A, the process was the same as in Example 1 to obtain an optical lens. Four of the obtained optical lenses were stacked and placed into an optical lens barrel to fabricate an optical lens unit. The physical properties of the obtained optical lens unit are shown in Table 1. Since the lens portion and the lens edge portion used the same resin A, the obtained optical lens did not undergo two-color molding. Furthermore, the lens edge portion did not have any non-transparent areas, either partially or entirely.

[0063] (Comparative Example 2) Four optical lenses obtained in Comparative Example 1 were sandwiched between their spacer portions, and a light-shielding material manufactured by Somalon Corporation (trade name: SOMABLACK) was placed in an optical lens barrel to manufacture an optical lens unit. The physical properties of the obtained optical lens unit are shown in Table 1.

[0064] [Table 1] (Example 4) Prepare resin D as described below.

[0065] <Preparation of Resin D> The following components, represented by the following structural formula (a) and with the isomers at positions 2,6 and 2,7 in a mass ratio of 50:50, are: 23.50 kg (105.7 mol) of D-NDM, 22.98 kg (107.3 mol) of diphenyl carbonate, and 0.13 g (1.5 × 10⁻⁶ mol) of sodium bicarbonate. －3(Moles) were placed in a 50L reactor equipped with a stirrer and a distillation device, and heated to 205°C over 1 hour under a nitrogen atmosphere of 760 Torr, with stirring. The temperature was adjusted to 205 Torr over 30 minutes and maintained at 205°C and 205 Torr for 30 minutes to initiate the transesterification reaction. After 30 minutes, the pressure was reduced from 205 Torr to 180 Torr over 20 minutes. While reducing the pressure, the temperature was increased to 215°C, and after 120 minutes of reaction initiation, the temperature was raised to 230°C, and the pressure was reduced to 150 Torr. After 180 minutes of reaction initiation, the temperature was raised to 240°C and the pressure was reduced to 1 Torr, then maintained for 20 minutes. After granulation, polycarbonate resin (a homopolymer of D-NDM, D-1) was obtained. The following components were prepared: 20.0 kg (45.6 mol) of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (BPEF), as shown in structural formula (b); 10.16 kg (47.4 mol) of diphenyl carbonate; and 0.03 g (3.6 × 10⁻⁶) of sodium bicarbonate. －4 (Moles) were placed in a 50L reactor equipped with a stirrer and distillation device, and heated to 205°C over 1 hour at 760 Torr under a nitrogen atmosphere with stirring. The temperature was adjusted to 205 Torr over 20 minutes and maintained at 205°C and 205 Torr for 30 minutes to initiate the transesterification reaction. After 30 minutes, the pressure was reduced from 205 Torr to 180 Torr over 20 minutes. While reducing the pressure, the temperature was increased to 215°C. 120 minutes after the start of the reaction, the temperature was increased to 230°C and the pressure reduced to 150 Torr. 180 minutes after the start of the reaction, the temperature was increased to 240°C and the pressure reduced to 1 Torr, then maintained for 20 minutes. After granulation, polycarbonate resin (D-2) was obtained.

[0066] In a mixture of 10.0 kg of polycarbonate resin (D-1) obtained from D-NDM and 4.8 kg of polycarbonate resin (D-2) obtained from BPEF, 14.8 g of hindered phenolic antioxidant (ADEKA AO-60), 4.4 g of phosphite antioxidant (trade name: PEP-36), and 14.8 g of glyceryl monostearate (RIKEN VITAMIN S-100A) as a release agent were added. The mixture was then compounded and granulated using a twin-screw extruder (IPEC-35) to obtain polycarbonate resin D. Furthermore, the obtained resin D is a resin containing the structural unit shown in formula (4) above. Prepare the following resin E.

[0067] <Preparation of Resin E> Resin E was prepared by melt mixing 10 kg of the above-obtained resin D with 100 g of resin colorant (manufactured by ORIENT Chemical Industry Co., Ltd., trade name: NUBIAN BLACK PC-5857) as a black dye using a twin-screw extruder.

[0068] <Fabrication of Optical Lenses and Optical Lens Units> Resin D and Resin E were heated and dried at 100°C for 3 hours respectively. Optical lenses were then obtained through two molding processes: insertion molding and two-color molding, with Resin D forming the lens portion and Resin E forming the lens edge portion. Four of the obtained optical lenses were overlapped and placed into an optical lens barrel to fabricate an optical lens unit. The physical properties of the obtained optical lens unit are shown in Table 2.

[0069] (Example 5) Prepare the following resin F.

[0070] <Preparation of Resin F> As raw materials, 4.53 kg (12.1 mol) of 2,2'-bis(2-hydroxyethoxy)-1,1'-bidinaphthalene (as shown in structural formula (c) below), 8.72 kg (14.8 mol) of 9,9-bis(4-(2-hydroxyethoxy)-3-phenylphenyl)fluorene (as shown in structural formula (d) below), 5.99 kg (27.9 mol) of DPC, and 2.5 × 10⁻⁶ ppm were used. －2 16 mL of sodium bicarbonate aqueous solution (4.0 × 10⁻⁶ mol / L) －4 One mole, i.e., the total amount of the dihydroxy compound, is 8.4 × 10⁻⁶. －6 (moles), except that, the same operation was performed as with resin A in Example 1 to obtain thermoplastic resin F. Furthermore, the obtained resin F is a resin containing the structural unit shown in formula (1) and the structural unit shown in formula (3) above. Prepare the following resin G.

[0071] <Preparation of Resin G> Resin G was prepared by melt mixing 10 kg of the above-obtained resin F with 100 g of resin colorant (manufactured by ORIENT Chemical Industry Co., Ltd., trade name: NUBIAN BLACK PC-5857) used as a black dye using a twin-screw extruder.

[0072] <Fabrication of Optical Lenses and Optical Lens Units> After heating and drying resin F and resin G at 100°C for 3 hours respectively, optical lenses were obtained by insertion molding and two-color molding, with resin F forming the lens part and resin G forming the lens edge part. Four optical lenses were stacked and placed into an optical lens barrel to fabricate an optical lens unit. The physical properties of the obtained optical lens unit are shown in Table 2.

[0073] [Table 2] Industrial availability The optical lens of this invention enables the thinning and miniaturization of optical lens units, and reduces light leakage caused by reflections from interfaces. This invention is suitable for use as a lens in cameras for smartphones, differential scanning calorimeters (DSC), automotive applications, etc.

Claims

1. An optical lens, comprising a lens portion having a light incident and exiting surface as an optically effective part and a lens edge portion having a surface other than the light incident and exiting surface as a non-optically effective part, characterized in that: The lens edge has a non-transparent portion in part or all of it. The edge portion of the lens covers the entire outer periphery of the lens portion. The lens portion and the lens edge portion contain the same thermoplastic resin. The thermoplastic resin comprises all structural units of the structural units shown in formula (1), formula (2), and formula (3), or It includes the structural unit shown in equation (4) below, or It includes the structural unit shown in equation (1) and the structural unit shown in equation (3). The non-transparent portion of the lens edge also contains one or more of a black dye and a black pigment, totaling 0.1 to 5% by mass. The lens portion and the lens edge portion are formed of two-color resin. The two-color resin is composed of transparent resin and black resin. The black resin is obtained by melt mixing with one or more of the black dye and black pigment in the same resin as the transparent resin. In formula (1), R1 and R2 independently represent hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group with 1 to 6 carbon atoms, aryl group with 6 to 20 carbon atoms that may contain heterocyclic atoms selected from O, N and S, alkenyl group with 2 to 6 carbon atoms, alkoxy group with 1 to 6 carbon atoms, or aralkyl group with 7 to 17 carbon atoms. a and b represent integers from 0 to 5 independently; In formula (2), R3 to R6 independently represent hydrogen atom, fluorine atom, chlorine atom, bromine atom, iodine atom, alkyl group with 1 to 6 carbon atoms, aryl group with 6 to 20 carbon atoms that may contain heterocyclic atoms selected from O, N and S, alkenyl group with 2 to 6 carbon atoms, alkoxy group with 1 to 6 carbon atoms, or aralkyl group with 7 to 17 carbon atoms. c and d independently represent integers from 0 to 6, and e and f independently represent integers from 0 to 4. In equation (3), R7~R 10 Each of the following can be independently represented: a hydrogen atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 20 carbon atoms that may contain heterocyclic atoms selected from O, N, and S, an alkenyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or an aralkyl group having 7 to 17 carbon atoms. g to j represent integers from 0 to 4 independently; In formula (4), R represents an alkyl group with 1 to 5 hydrogen atoms or carbon atoms.

2. The optical lens as described in claim 1, characterized in that: For use in smartphones.

3. An optical lens unit, characterized in that: It includes the optical lens as described in claim 1 or 2.

4. The optical lens unit as described in claim 3, characterized in that: No spacers included.

5. A method for manufacturing an optical lens, used to manufacture the optical lens of claim 1, characterized in that: The lens portion and the lens edge portion are integrally formed using two molding methods: insert molding and two-color molding.

Images