Method for manufacturing lens modules, optical devices, imaging devices, electronic devices, and lens units.

Abstract

To obtain a lens module with good optical properties. [Solution] A lens module comprising a first unit having a first lens and a first holder made of a different material from the first lens for holding the first lens, and a second unit having a second lens and a second holder made of a different material from the second lens for holding the second lens, wherein the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together.

Description

Technical Field

[0001] The present invention relates to a lens module, an optical device, an imaging device, an electronic device, and a method for manufacturing the lens unit.

Background Art

[0002] In recent years, due to the high-precision improvement of CMOS sensors and the development of communication technologies, cameras are installed in various devices, and the demand for small lens modules (lens units) composed of a plurality of lenses and used in these cameras has been increasing. In addition, in this small lens module, small-diameter plastic lenses are frequently used.

[0003] Patent Document 1 discloses a lens group in which a first lens configuration layer LY1 having a first lens G1 and a non-lens portion and a second lens configuration layer LY2 having a second lens G1 are coupled via a spacer layer RB.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the configuration disclosed in Patent Document 1, the alignment of each lens may be inappropriate, and good optical characteristics may not be obtained.

[0006] In view of such a situation, an object of the present invention is to provide a lens module having good optical characteristics, an optical device, an imaging device, and an electronic device using the lens module, and a method for manufacturing the lens unit.

Means for Solving the Problems

[0007] To achieve the above objective, a lens module according to one aspect of the present invention is: A first unit having a first lens and a first holder made of a different material from the first lens and holding the first lens, A second unit comprising a second lens, a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together. [Effects of the Invention]

[0008] According to one aspect of the present invention, a lens module having good optical properties, an optical device using the lens module, an imaging device, and an electronic device can be provided. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view of a lens module according to Embodiment 1 of the present invention. [Figure 2] Figure 1 is a cross-sectional view of the lens module shown as an example. [Figure 3] The method for manufacturing a lens module according to an embodiment of the present invention is shown. [Figure 4] Figure 1 is a perspective view of the units included in the lens module shown as an example. [Figure 5] Figure 1 is a schematic cross-sectional diagram illustrating the taper alignment when joining multiple units in the lens module shown as an example. [Figure 6] This is a schematic cross-sectional diagram illustrating the bonding state of the two units in the lens module shown in Figure 1. [Figure 7] This is a schematic cross-sectional diagram illustrating the bonding state of the three units in the lens module shown in Figure 1. [Figure 8]It is a schematic cross-sectional view for explaining the joining state of three holder-integrated lens modules and a light-shielding member in the lens module illustrated in FIG. 1. [Figure 9] It is a schematic cross-sectional view for explaining the joining state of four units in the lens module illustrated in FIG. 1. [Figure 10] It is a perspective view for explaining an example of a method for joining units. [Figure 11] It is a plan view showing the arrangement of positioning protrusions in the lens module according to Example 2 of the present invention. [Figure 12] It is a schematic cross-sectional view showing a part of an assembling method using the positioning protrusions in Example 2. [Figure 13] It is a schematic cross-sectional view showing other aspects in Example 2. [Figure 14] It is a schematic cross-sectional view showing other aspects in Example 2. [Figure 15] It is a perspective view of the lens module according to Example 3 of the present invention. [Figure 16] It is a schematic cross-sectional view for explaining an assembling method of the lens module illustrated in FIG. 15. [Figure 17] It is a schematic cross-sectional view for explaining an assembling method of the lens module according to Example 4 of the present invention. [Figure 18] It is a view showing an example of an imaging device using the lens module according to the present invention. [Figure 19] It is a view showing an example of an information terminal using the lens module according to the present invention.

Embodiments for Carrying Out the Invention

[0010] Hereinafter, embodiments for carrying out the present invention will be described as examples with reference to the drawings. However, the embodiments described below are only one embodiment of the invention and are not limited thereto. Although several features are described in the embodiments, not all of these features are essential to the invention, and the features may be combined arbitrarily. Furthermore, the dimensions, materials, and relative positions of components described in the following embodiments are arbitrary and can be changed according to the configuration of the device to which the present invention is applied or various conditions.

[0011] Furthermore, common components are explained by referencing multiple drawings, and explanations of components with common reference numerals are omitted as appropriate. Different items with the same name can be distinguished by adding "Item 1," "Item 2," etc. Also, terms such as "approximately identical" and "approximately the same," as described below, refer to a state where identical or identical can be described when considering differences in dimensional accuracy that may occur during assembly due to manufacturing errors or during the manufacturing of individual components.

[0012] <Example 1> A lens unit (lens module 100) according to Embodiment 1 of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a perspective view of the lens module 100. The lens module 100 according to this embodiment comprises a lens portion 1 made of a transparent material and a lens barrel 101 arranged on the outer circumference of the lens portion 1.

[0013] Figure 2 is a cross-sectional view showing the schematic configuration of the lens module 100 in a plane including the optical axis P. The lens module 100 according to Embodiment 1 is composed of four units 41, 42, 43, and 44, which are the first to fourth units, respectively. Each unit consists of a partial lens barrel and a lens integrally joined to the partial lens barrel. In this embodiment, unit 41 includes a lens 11, which is the first lens, and a partial lens barrel 21, which is the first holder. Unit 42 includes a lens 12, which is the second lens, and a partial lens barrel 22, which is the second holder. Unit 43 includes a lens 13 and a partial lens barrel 23, and unit 44 includes a lens 14 and a partial lens barrel 24. A light-shielding member 31, which will be described later, is placed between unit 43 and unit 44.

[0014] The four units 41, 42, 43, and 44 are arranged such that their respective lenses 11, 12, 13, and 14 are aligned in this order from the objective side to the image sensor side. Furthermore, the optical axes of each lens 11, 12, 13, and 14 are positioned to approximately coincide with the optical axis P, and in this state, they are integrally joined together, for example, by adhesive. The lens barrel 101 shown in Figure 1 is composed of partial lens barrels 21, 22, 23, and 24, and the lens section 1 consists of lenses 11, 12, 13, and 14 housed inside the lens barrel 101, and a light-shielding member 31. In the example shown in the figure, lens 11 is located on the objective side, and lens 14 is located on the image sensor side (not shown).

[0015] Next, the method for manufacturing a lens module according to the present invention will be described with reference to Figures 3 to 10. The method for manufacturing a lens module according to the present invention includes a first manufacturing step to a third manufacturing step (steps S301 to S303) as shown in the flowchart of Figure 3. Hereinafter, each manufacturing step when manufacturing the lens module 100 illustrated in Figures 1 and 2 will be described.

[0016] In the manufacturing of the lens module, the first manufacturing process in step S301 is performed first. In the first manufacturing process, each of the four units 41, 42, 43, and 44 of the lens module 100 illustrated in Figure 2 is manufactured. Here, as an example, the manufacturing process for unit 41 will be described.

[0017] Figure 4 is a perspective view of unit 41. Here, an example is described in which unit 41 is manufactured so that the lens 11 and the partial lens barrel 21 are integrally joined by insert molding. Note that the manufacturing method of the unit is not limited to the insert molding method exemplified here, and other known manufacturing methods can be applied to the present invention as long as the lens and the partial lens barrel can be manufactured integrally. Two-color molding is a method that allows the lens and the partial lens barrel to be integrally molded using a composite mold that integrates a mold for the first color and a mold for the second color. Two-color molding can be considered a type of insert molding method in that the molded body of the first color is placed in the mold for the second color when the second color is molded.

[0018] In the actual manufacturing method, a pre-fabricated portion of the lens barrel 21 is provided with a pre-fabricated flow path for the gate 111 used for lens molding. This portion of the lens barrel 21 is then placed in a mold, and the material for forming the lens 11 is poured through the flow path of the gate 111. Through this process, a unit 41 is manufactured in which the portion of the lens barrel 21 and the lens 11 are integrally joined.

[0019] The first material used to manufacture the lens 11 can be a transparent resin such as polycarbonate, acrylic, or cyclic olefin polymer (cycloolefin polymer). Alternatively, a glass material such as BK7 may be used as the first material, and the choice can be based on the required lens performance for the lens 11. The glass transition temperature (Tg) of polycarbonate is 140-150°C, and the coefficient of thermal expansion of polycarbonate is 3-7 × 10⁻⁶. -5 The temperature is / ℃. The glass transition temperature (Tg) of acrylic is 100~120℃, and the coefficient of linear expansion of acrylic is 5~9 × 10⁻⁶. -5The temperature is / °C. The glass transition temperature (Tg) of cyclic olefin polymers is 130-150°C, and the coefficient of linear expansion of cyclic olefin polymers is 6-7 × 10⁻⁶. -5 It is / ℃.

[0020] It is desirable that the partial lens barrel 21 be made of a second material different from the material of the lens 11, such as a black resin material, in order to prevent stray light. If the lens 11 is made of a resin material, the resin material of the lens 11 may be integrated with the resin material of the partial lens barrel 21 in a compatible state. Compatible means that there is no clear interface at the boundary between the partial lens barrel 21 and the lens 11, and the two materials diffuse and integrate. In this case, the resin material of the lens 11 can be said to be compatible with the resin material of the partial lens barrel 21. Incompatible means that there is a clear boundary between the partial lens barrel 21 and the lens 11, and they are mechanically joined by an anchor structure. Even if the lens 11 is made of a resin material, it may be in contact with the resin material of the partial lens barrel 21 by forming an interface such that the resin material of the lens 11 integrates with the resin material of the partial lens barrel 21 in an incompatible state. In this case, the resin material of the lens 11 is incompatible with the resin material of the partial lens barrel 21. Incompatible means that the material of the partial lens barrel 21 and the material of the lens 11 form an interface at their boundary, making them in contact and integrated.

[0021] Resin materials compatible with polycarbonate, as exemplified for the resin material of lens 11, include polycarbonate, acrylonitrile butadiene styrene, and polybutylene terephthalate, and these can be used as the resin material for the partial lens barrel 21. Resin materials incompatible with polycarbonate, as exemplified for the resin material of lens 11, include polyethylene, polypropylene, polyacetal, nylon, and polyphenylene sulfide, and these can be used as the resin material for the partial lens barrel 21.

[0022] Resin materials compatible with acrylic, as exemplified for the resin material of lens 11, include polystyrene and acrylic, and these can be used as the resin material for the partial lens barrel 21. Resin materials incompatible with acrylic, as exemplified for the resin material of lens 11, include polyethylene, polypropylene, polyacetal, nylon, and polyphenylene sulfide, and these can be used as the resin material for the partial lens barrel 21.

[0023] Examples of resin materials compatible with the cyclic olefin polymer exemplified as the resin material for lens 11 include polyethylene and polypropylene. The resin material for the partial lens barrel 21 can be the materials exemplified here. Examples of resin materials incompatible with the cyclic olefin polymer exemplified as the resin material for lens 11 include polycarbonate, polybutylene terephthalate, polyetheretherketone, and polyphenylene sulfide. The resin material for the partial lens barrel 21 can be the materials exemplified here.

[0024] When selecting compatible resin materials for the lens 11 and the partial lens barrel 21, a strong joint surface can be obtained when the lens 11 and the partial lens barrel 21 are insert-molded to form a molded body. This makes it less likely for the lens 11 to detach from the partial lens barrel 21 when external forces are applied during assembly of the units or during use of the lens module 100. On the other hand, when selecting incompatible resin materials for the lens 11 and the partial lens barrel 21, the joint surface between the lens 11 and the partial lens barrel 21 is joined by friction, resulting in a weaker joint surface than that of compatible combinations. In this case, the configuration is advantageous when temperature changes occur in the lens module 100. This is because, when there is a difference in the coefficient of linear expansion between the materials of the lens 11 and the partial lens barrel 21, a temperature change will cause the material with the larger coefficient of linear expansion to exert a pulling force on the material with the smaller coefficient of linear expansion, which can cause deformation of the optical surface of the lens 11. However, because it is incompatible and does not have a strong bonding surface, the frictional and elastic forces of the bonding surface can absorb the tensile force, making it difficult for the tensile force generated at the bonding surface to be transmitted to the optical functional surface of the lens 11. As a result, when an incompatible resin material is selected, deformation of the optical functional surface of the lens 11 due to temperature changes can be suppressed.

[0025] When an amorphous resin such as acrylonitrile butadiene styrene or polycarbonate is selected as the resin material for the partial lens barrel 21, it is desirable that the glass transition temperature of the lens 11 resin material be lower than that of the partial lens barrel 21 resin material. With such a material, when the lens 11, which is the second molded part in insert molding, is injection molded, the effect of thermal deformation of the surface properties of the partial lens barrel 21 is reduced when the molten lens resin material passes over the surface of the partial lens barrel 21. As a result, it is possible to maintain the shape of functional surfaces such as the embossed surface for light shielding formed on the partial lens barrel 21.

[0026] When a crystalline resin such as polyethylene or polypropylene is selected as the resin material for the partial lens barrel 21, it is desirable that the glass transition temperature of the lens 11 resin material be lower than the melting point of the partial lens barrel 21 resin material. This is because, as with the case where an amorphous resin is selected for the partial lens barrel 21, when the lens 11, which is the second molded part in insert molding, is injection molded, the molten lens resin material is more likely to maintain the shape of the functional surface of the partial lens barrel 21 after passing through the surface of the partial lens barrel.

[0027] It is preferable that the coefficient of linear expansion of the resin material of the lens 11 is between 1 / 5 and 5 times the coefficient of linear expansion of the resin material of the partial lens barrel 21. This is because if the difference in the coefficients of linear expansion between the lens 11 and the partial lens barrel 21 is large when a temperature change occurs in the lens module 100, stress due to the difference in thermal expansion will occur at the joint surface between the lens 11 and the partial lens barrel 21. As a result, the shape of the lens surface may be distorted, and the optical performance of the lens module 100 may deteriorate. Therefore, in order to further reduce the stress caused by the difference in thermal expansion, it is preferable that the coefficient of linear expansion of the resin material of the lens 11 be between 1 / 3 and 3 times the coefficient of linear expansion of the resin material of the partial lens barrel 21, if possible. In other words, in order to reduce such a difference in thermal expansion, it is preferable that the combination of materials for the lens 11 and the partial lens barrel 21 have similar coefficients of linear expansion. Specifically, in view of the preferred coefficient of linear expansion of the first material constituting the lens 11 described above, the coefficients of linear expansion of the first material and the second material should be 2 to 8 × 10⁻⁶. -5 A temperature of / ℃ is preferable.

[0028] Considering the above, when a cyclic olefin polymer is used as the resin material for the lens 11, polycarbonate is suitable as the resin material for the partial lens barrel 21.

[0029] Furthermore, the partial lens barrel 21 in this embodiment has a tapered partial lens barrel fitting portion 211, as illustrated in Figure 4. More specifically, as shown in the cross-section of Figure 5, the partial lens barrel fitting portion 211 is provided so as to protrude toward the unit 42 from the end face 21a of the partial lens barrel 21 that is positioned toward the unit 42 when the lens module 100 is formed.

[0030] The tapered central axis of the partial lens barrel fitting portion 211 and the central axis of the lens 11 are aligned approximately identically. The partial lens barrel fitting portion 211 has a tapered shape that forms a frustoconical shape in its outer form, with the diameter decreasing as it approaches the unit 42 during the assembly of the lens module 100. The tapered shape of this partial lens barrel fitting portion 211 and the partial lens barrel fitting portion 221, which has a tapered shape and is provided in the partial lens barrel 22 corresponding to the partial lens barrel fitting portion 211, are used in the assembly. This allows the position of the respective lens central axes in unit 41 and unit 42 to be defined. These partial lens barrel fitting portions function as an example of positioning portions for determining the relative positions of the units when they are joined together. The partial lens barrel fitting portion 211 described here functions as a partial lens barrel positioning portion.

[0031] Furthermore, to more firmly integrate the lens 11 and the partial lens barrel 21, a rough surface or undercut shape may be provided on the side surface of the lens 11 or on the inner diameter of the partial lens barrel 21. In the illustrated example, the surface of the partial lens barrel 21 that contacts the outer surface of the lens 11 is joined to this outer surface. Therefore, the contact surface of the partial lens barrel 21 with the lens 11 functions as a surface that holds the lens 11, and according to the unit molding method described above, the roughness of the holding surface matches the roughness of the outer surface of the first lens, the lens 11. In addition, the unit can be obtained by molding the lens and the partial lens barrel separately and press-fitting the lens into the inner diameter of the partial lens barrel, or by integrating them with adhesive or heat riveting. Furthermore, multiple lenses may be integrally bonded to the partial lens barrel.

[0032] Units 42, 43, and 44 are manufactured using the same process as Unit 41 illustrated above, or using known manufacturing processes. In this process, a partial lens barrel fitting portion 221 having a tapered shape corresponding to the partial lens barrel fitting portion 211 is formed on the end face 22b of the partial lens barrel 22 in Unit 42. In addition, a partial lens barrel fitting portion 222 having a tapered shape similar to the partial lens barrel fitting portion 211 is formed on Unit 42 so as to protrude from the end face 22a of the partial lens barrel 22 toward the partial lens barrel 23 (see Figure 5).

[0033] Furthermore, the unit 43 has a tapered portion 231 formed on the end face 23b of the partial lens barrel 23, which corresponds to the partial lens barrel fitting portion 222 (see Figure 7). The unit 43 also has a tapered portion 232 formed on the unit 43, which has a similar tapered shape to the partial lens barrel fitting portion 211 and is provided to protrude from the end face 23a of the partial lens barrel 23 toward the partial lens barrel 24 (see Figure 7). In this embodiment of the lens module 100, a light-shielding member 31 is placed between the lens 13 and the lens 14 (see Figure 8). For this reason, the partial lens barrel 23 is provided with a light-shielding member housing portion 234, which consists of a recess corresponding to the outer shape of the light-shielding member 31, in order to accommodate the annular light-shielding member 31.

[0034] Then, a tapered portion 241 corresponding to the portion tube fitting portion 232 is formed on the end face 24b of the portion tube 24 of unit 44 (see Figure 9). Once the four units 41, 42, 43, and 44 having the above structures are prepared, the flow moves on to the second manufacturing process of step S302.

[0035] In the second manufacturing step S302, the four units 41, 42, 43, and 44 are stacked in this order along the extending direction of the optical axis P. Details of the stacking process will be explained below with reference to Figures 5 to 9. Figures 5 to 9 are diagrams that sequentially show the process of stacking the four units, and schematically show the structure of the cross-section obtained by cutting these components along the direction of the optical axis P.

[0036] First, the stacking process of units 41 and 42 will be explained with reference to Figures 5 and 6. The two units 41 and 42 manufactured in the first manufacturing process each have a partial barrel fitting portion 211 and a partial barrel fitting portion 221 formed thereon. The central axes of the respective partial barrel fitting portions 211 and 221 are aligned with the central axes of lenses 11 and 12, and by fitting the partial barrel fitting portion 211 into the partial barrel fitting portion 221, the central axes of these lenses 11 and 12 are aligned within the lens barrel.

[0037] The convex taper of the partial lens barrel fitting portion 211 and the concave taper of the partial lens barrel fitting portion 221 are configured to have approximately the same taper angle. Furthermore, the inner diameter of the concave taper is set to be larger than the outer diameter of the convex taper. As a result, as shown in Figure 6, the end face 21a of the partial lens barrel of unit 41 and the end face 22b of the partial lens barrel of unit 42 are guided by the tapers of each partial lens barrel fitting portion 211 and 221 and come into contact. At this time, the distance L between lenses 11 and lens 12 is determined by the position of the contact surfaces.

[0038] In this embodiment, a mask portion 224 is provided at the opening of the partial lens barrel 22. The mask portion 224 has an inner diameter that decreases from the unit 43 side to the unit 41 side, thereby blocking unwanted light passing through the flange portion of the lens 11 and preventing stray light.

[0039] In conventional technology, lenses and light-shielding parts are assembled sequentially from one direction to an integrated lens barrel. Therefore, it is not possible to create an inner diameter portion narrower than the outer diameter of the component being assembled on the lens barrel on the side of the component facing that direction. However, in this embodiment, the lens barrel is divided into multiple sub-lens barrels, and a lens module is obtained by stacking these individually. Therefore, an opening narrower than the maximum diameter component can be formed regardless of the arrangement of each of the multiple lenses and light-shielding parts. Accordingly, as a configuration that replaces conventional light-shielding parts, it is possible to integrate the mask portion 224 exemplified above with the sub-lens barrel 22 and mold it, thereby reducing the number of parts. Note that the mask portion is not limited to the sub-lens barrel 22, but may be provided on other sub-lens barrels as well.

[0040] After stacking units 41 and 42, unit 43 is then stacked on top of unit 42, as shown in Figure 7. At this time, the convex taper of the partial barrel fitting portion 222 and the concave taper of the partial barrel fitting portion 231 are configured to have approximately the same taper angle. In addition, the inner diameter of the concave taper is set to be larger than the outer diameter of the convex taper. As a result, as shown in Figure 7, the end face 22a of the partial barrel of unit 42 and the end face 23b of the partial barrel of unit 43 come into contact with each other, guided by the taper of each partial barrel fitting portion 222 and 231.

[0041] Furthermore, in this embodiment, a light-shielding member 31 is positioned between unit 43 and unit 44. In these assembly steps, as shown in Figure 8, the light-shielding member 31 is placed in the light-shielding member housing portion 234 of unit 43, and then unit 44 is placed on top to fix the position of the light-shielding member 31. At that time, similar to when units 41, 42, and 43 are stacked, the joining position is guided by the convex-shaped partial lens barrel fitting portion 232 and the concave-shaped partial lens barrel fitting portion 241, which have approximately the same angle. Then, as shown in Figure 9, the end face 23a of the partial lens barrel of unit 43 and the end face 24b of the partial lens barrel of unit 44 come into contact.

[0042] The lens module 100 is formed by stacking each unit in these processes. In the assembly of each unit, the tapered portion and the contact surface of the partial lens barrel, which align the optical axes of each lens, should be rotatable about the optical axis to allow for lens phase adjustment during assembly. Furthermore, to facilitate the assembly process, a positioning shape for defining the rotation phase may be provided. Once the four units 41, 42, 43, and 44 are integrally stacked along the optical axis P through the above processes, the flow moves to the third manufacturing process in step S303.

[0043] In the third manufacturing step, S303, the fitted and positioned units 41, 42, 43, and 44 are fixed in place. The units can be integrated by joining the side portions of their respective lens barrels. An example of the integration method will be explained with reference to Figure 10. Figure 10 is a schematic perspective view of the lens module 100 illustrating an example of the integration method.

[0044] As shown in Figure 10, each section of the lens module 100 is provided with a notch 25 on the side of the lens barrel that forms a continuous groove when the units are stacked. By applying an adhesive (not shown) to this notch 25 and allowing it to harden, the units are joined together and integrated. The adhesive used can be a thermoplastic resin, an energy-curing resin, or a super glue, but one that does not cause fogging or other problems due to outgassing and does not degrade the optical performance of the lens is more suitable. In addition, the joining of the section lens units may also be done by other methods, such as heating and welding the side of each section of the lens barrel. Furthermore, although the lens module 100 is obtained here using the above-described units for all four lenses, for example, only units 42 and 43 may be configured as described above, and lenses 11 and 14 may be used without being part of a unit. Alternatively, units 41, 42, and 43 may be used, and lens 14 may be used without being part of a unit.

[0045] Regarding lens modules used in small cameras and the like, the above-described configuration makes assembly easier and reduces assembly costs compared to conventional small lenses. Furthermore, it becomes possible to reduce the number of parts, which also contributes to lowering assembly costs.

[0046] <Example 2> In Example 1, when stacking the units, the tapered partial lens barrel fitting portion provided on each unit was used as a positioning part to align the optical axes of each lens. In contrast, in Example 2, a further alignment structure is provided for each unit to achieve more favorable alignment. The shapes of units 41A and 42A in this embodiment and the steps corresponding to the steps illustrated in Figures 5 and 6 in step S302 will be described below with reference to Figures 11 and 12. In the following description, parts having similar functions and structures to units 41 and 42 described in Example 1 will be given the same reference numerals and their descriptions will be omitted below. Figure 11 shows a top view of the end face 21a of unit 41A and a top view of the end face 22b of unit 42A. Figure 12 shows units 41A and 42A stacked on top of each other in the same manner as in Figure 6 in Example 1.

[0047] In Embodiment 1, the optical axes of each unit 41 and 42 were aligned by aligning the partial lens barrel fitting portions 211 and 221. The distance L between lenses 11 and 12 was defined by the end face 21a of the partial lens barrel 21 and the end face 22b of the partial lens barrel 22. More specifically, it was defined by the lens surfaces of lens 11 and lens 12, whose positions in the optical axis direction were set with respect to these end faces. In contrast, in Embodiment 2, in order to define the distance between lens 11 and lens 12, positioning grooves 215 and positioning projections 225 are provided on units 41A and 42A, respectively.

[0048] The positioning grooves 215 and positioning projections 225 are provided at the same phase, with three or more points each on the partial lens barrel 21A and the partial lens barrel 22A. In this embodiment, the case in which three positioning grooves 215 and positioning projections 225 are provided is illustrated. The positioning projections 225 are provided so as to protrude from the end face 22b toward the unit 41A when stacked. The positioning grooves 215 are formed as triangular grooves in cross-section extending from the inside to the outside of the end face 21a, and are shaped so that when the positioning projections 225 are installed, the projections abut against the inclined portion of the groove.

[0049] By arranging these grooves and protrusions, the distance between lens 11 and lens 12 can be controlled by the dimensions of the positioning groove 215 and positioning protrusion 225. This enables more precise adjustment of the distance L between lenses. Furthermore, since the position of the positioning protrusion 225 is fixed in the direction of optical axis rotation by fitting it into the positioning groove 215, the rotational position in the direction of the optical axis in step S302 becomes easier. Note that the shapes of the positioning groove 215 and positioning protrusion 225 shown in this embodiment are just examples of positioning parts, and these shapes are not limited to those exemplified, as long as similar effects can be obtained.

[0050] Furthermore, in this embodiment, the optical axis positioning of the unit can also be performed using only the positioning groove 215 and the positioning projection 225. Figure 13 shows such an embodiment in the second embodiment in the same style as Figure 12. In the illustrated unit 41B, the partial lens barrel 21B lacks the partial lens barrel fitting portion 211 in Figure 12, and the end face 21a extends to the region where the partial lens barrel fitting portion 211 was located. As a result, a part of the lens 11 is positioned in the space provided between the partial lens barrel 21B and the partial lens barrel 22A. By providing such a configuration for the lens module, it becomes possible to select a wider variety of lens shapes for use in the lens module.

[0051] Figure 14 shows a further aspect of the second embodiment in the same style as Figure 12. In the illustrated unit 41A, the lens 11B is thinner near the outer circumference of the lens 11 in Figure 12, and the partial lens barrel fitting portion 211 is located closer to the partial lens barrel 22A than the outer circumference of the lens 11B. As a result, a part of the partial lens barrel 21A is positioned within the space provided between the lens 11B and the lens 12. By providing such a configuration for the lens module, it becomes possible to select a wider range of lens shapes for use in the lens module.

[0052] <Example 3> In Example 1, a lens module 100 with four lenses was described. In the present invention, the number of lenses arranged in a lens module is not limited to four. In Example 3, the shape and manufacturing method of a lens module 100C with two lenses are shown. Below, as Example 3, the lens module 100C in this example will be described using Figures 15 and 16. Figure 15 is a perspective view of the lens module 100C in this example. Figure 16 is a diagram that shows the cross-section of the unit and explains the process described in step S302 of the flowchart in Figure 2 step by step, similar to Figure 5. In this example, two units 41C and 42C are stacked to form a lens barrel 101C, and the lens section 1C includes lens 11 and lens 12.

[0053] The manufacturing method of the lens module 100C according to this embodiment will be described below with reference to Figure 16. In the following description, parts having similar functions and structures to units 41 and 42 described in Example 1 will be given the same reference numerals, and their descriptions will be omitted below. First, as shown in Figure 16(a), units 41C and 42C are made using the same method as described in step S301 of Example 1. An annular light-shielding member 31 is also prepared.

[0054] In the subsequent step S302, first, as shown in Figure 16(b), the light-shielding member 31 is placed on the unit 41C. In this embodiment, the light-shielding member 31 is placed on at least one of the end face 21c, which is the upper surface of the partial lens barrel fitting portion 211 of the unit 41C, and the outer peripheral surface 11a of the lens 11 on the lens 12 side. Next, as shown in Figure 16(c), the unit 42C is placed on top of the unit 41C and the light-shielding member 31.

[0055] In this case, as in Embodiment 1, units 41C and 42C are provided with partial lens barrel fitting portions 211 and 221, respectively, which are aligned with the optical axes of lenses 11 and 12. By fitting these together, units 41C and 42C can be assembled while aligning their optical axes. As in Embodiment 1, in the process of assembling the three components of units 41C, 42C and the light-shielding member 31, the distance L between lenses 11 and 12 can be determined by the end faces 21a and 22b. However, in this embodiment, since the light-shielding member 31 is sandwiched between units 41C and 42C while in contact with them, the distance L between lenses can also be determined by the thickness of the light-shielding member 31.

[0056] In this embodiment, it is shown that the present invention is applicable not only to lens modules consisting of four lenses, but also to lens modules consisting of multiple lenses, such as lens modules consisting of two lenses. However, the present invention is applicable to lens modules other than those exemplified. For example, for lens modules consisting of lens groups that are relatively easy to assemble, a configuration in which these lens groups are inserted into a single lens barrel is used. For lens groups that are difficult to assemble, the lens module according to the present invention is used, and these can be combined to obtain the final lens module. In other words, the present invention is applicable to any lens module that includes at least two of the above-described units. Furthermore, the lens module according to the present invention may be used in combination with conventional lenses. Specifically, a lens module can be obtained by combining one or more units according to the present invention with one or more lenses. Also, when obtaining a lens module by stacking multiple lenses in the optical axis direction in this way, it is preferable to place conventional lenses, which are relatively easy to align, in the front, rear, or both directions in the optical axis direction, and to place the above-described units in the middle of the optical axis direction, where alignment is relatively difficult.

[0057] <Example 4> Example 4 is a modified version of the process shown in step S303 of Example 1 in the flowchart of Figure 3. In this example, instead of welding or bonding multiple units together, when stacking in step S302, the units are integrated using press-fit shapes arranged between adjacent units. The manufacturing method of the lens module 100D in this example will be described below with reference to Figure 17. Here, we will describe the case where there are two lenses as described in Example 3. In the following description, parts having similar functions and structures to units 41 and 42 described in Example 1 will be given the same reference numerals, and their descriptions will be omitted below.

[0058] In this embodiment, units 41D and 42D are provided with press-fit projections 311 and press-fit grooves 312, respectively, for engagement during assembly. The press-fit projection 311 is formed in the partial lens barrel 21D of unit 41D so as to protrude from the end face 21a facing the partial lens barrel 22D of unit 42D. The press-fit groove 312 is formed in the partial lens barrel 22D as a groove or hole of a size that allows the press-fit projection 311 to be fitted into the end face 22b facing the partial lens barrel 21D. The press-fit projection 311 and the press-fit groove 312 are arranged in corresponding locations in each unit, and the press-fit groove 312 is manufactured to a size that allows the press-fit projection 311 to be press-fitted.

[0059] In the actual manufacturing process, the two units and the light-shielding member 31 shown in Figure 17(a) are arranged, and the light-shielding member 31 is placed on unit 41D as shown in Figure 17(b). Subsequently, as shown in Figure 17(c), units 41D and 42D are stacked on top of each other and fixed in place.

[0060] Next, the details of the fixing process will be explained. First, the optical axes of units 41D and 42D are aligned. Specifically, the partial barrel fitting portions 211 and 221 come into contact first. While aligning the optical axes with the partial barrel fitting portions 211 and 221, the end face 21a of unit 41D and the end face 22b of unit 42D are fitted together so that they are brought closer together. After that, the press-fit projection 311 is inserted into the opening of the press-fit groove 312. The press-fit projection 311 and the press-fit groove 312 have shapes and dimensions that allow them to be fixed together by pushing, driving, or press-fitting, that is, they have an overlap that prevents the parts from moving relative to each other when engaged.

[0061] The press-fit projection 311 is given a tapered shape, which allows it to be easily introduced into the press-fit groove 312 during press-fitting. After press-fitting, the units 41D and 42D are fixed by crushing the overlap provided on the press-fit projection 311, and the lens module 100D is created. In this example, the press-fit projection 311 is provided on unit 41D and the press-fit groove 312 is provided on unit 42D, but these may be arranged in reverse. Also, if multiple units are provided, a portion of the press-fit projection 311 and a portion of the press-fit groove 312 may be divided and provided on the second units 41D and 42D.

[0062] <Other examples> As described above, the lens module according to the present invention facilitates assembly and reduces assembly costs during the manufacturing of the lens module. Furthermore, the present invention can be applied to optical devices including imaging devices, such as cameras, that use these lens modules, and to information terminals, such as smartphones. Figure 18 shows an imaging device, which is an example of an optical device using a lens module. Figure 18(a) is a perspective view of the imaging device 1800, and Figure 18(b) is a schematic diagram showing the optical configuration within the imaging device 1800.

[0063] The imaging device 1800 comprises a housing 1802, a lens module 100 as illustrated in Figure 1, an image sensor 1804, and an optical system 1803 that forms an image on the image sensor 1804 of light that has passed through the lens module 100. The image sensor 1804 receives light from an unillustrated subject that has passed through the lens module 100. By applying the present invention to the imaging device 1800, the cost of optical elements such as lenses can be reduced. Furthermore, in the lens module 100, the limitations on the effective optical diameter of the lens used are reduced compared to conventional lens modules, which is expected to increase design flexibility.

[0064] Figure 19 shows a perspective view of a smartphone 1900, an example of an information terminal which is an electronic device using the lens module 100 illustrated in Figure 1, etc. The smartphone 1900 uses the lens module 100 in the imaging function unit provided in the main body 1901. In addition, a light-emitting element 1902 used as a flash to illuminate the object to be imaged is provided next to the lens module 100. The lens module 100 according to the present invention is easy to miniaturize, which is expected to greatly increase the design freedom of smartphones. Furthermore, since such electronic devices require a tiny lens module, it can also be applied to endoscopes where a light-emitting element needs to be placed at the tip along with the lens module. When the lens module according to the present invention is used at the tip of an endoscope, it becomes possible to greatly increase the freedom of placement of the light-emitting element, and the design freedom of the endoscope itself can also be increased.

[0065] As described above, the lens module (100) according to the present invention comprises at least two units, for example, unit (41) and unit (42). Unit (41) has a lens (11) and a partial lens barrel (21) that integrally holds the lens (11). Unit (42) has a lens (12) and a partial lens barrel (22) that integrally holds the lens (12). Unit (42) is joined to unit (41) such that the optical axis of lens (11) and the optical axis of lens (12) coincide. In this invention, the aforementioned partial lens barrel can also be called a holder because it holds the lens. By joining individual units in this way so that the optical axes of the individual lenses coincide, it is possible to simplify the assembly of the lens module (100) and reduce the assembly cost.

[0066] The number of units to be joined can be changed depending on the optical performance required for the lens module. Furthermore, the partial lens barrels (21) and (22) can be made of light-shielding material to suppress stray light transmitted through the lens. In this case, the partial lens barrels made of light-shielding material can be arranged in a line as described above, or, for example, partial lens barrels (21) and (23) can be formed from light-shielding material, depending on the optical performance required for the lens module.

[0067] Furthermore, as illustrated in Figure 13, a portion of lens 11 or a portion of lens (12) may be positioned in the region between the partial lens barrel 21B and the partial lens barrel 22A with respect to the extending direction of the optical axis P. In the illustrated example, a portion of lens 11 is located in this region, but by changing the shape of the partial lens barrel 22A, for example, a portion of lens 12 can also be positioned in this region. Also, as illustrated in Figure 14, a portion of partial lens barrel 21 or a portion of partial lens barrel 22A may be positioned in the region between lens 11B and lens 12 with respect to the extending direction of the optical axis P. In the illustrated example, a portion of partial lens barrel 21A (partial lens barrel fitting portion 211) is located in this region, but by changing the shape of lens 12, for example, a portion of partial lens barrel 22A can also be positioned in this region.

[0068] Furthermore, in the lens module (100) described above, the partial lens barrel (21) and the partial lens barrel (22) can be in contact with each other by contactable surfaces (21a, 22b). By joining the unit (41) and the unit (42) with these surfaces in contact, the distance L between the lenses (11) and the lens (12) can be set to a desired value.

[0069] Furthermore, in the structure of the unit, as illustrated in Figure 5, for example, a part of the partial lens barrel 21 is provided to be joined to a part of the outer circumference of the lens 11. As illustrated in Figure 4, the unit can be obtained by insert molding of the lens into the partial lens barrel. In this case, in the partial lens barrel 21, the surface roughness of the surface on which the partial lens barrel 21 holds the lens 11 is the same as the surface roughness of the surface on which the lens 11 is held by the partial lens barrel 21.

[0070] Furthermore, in the lens module (100) described above, positioning parts can be provided in the partial lens barrels. For example, as illustrated in Figure 5, the partial lens barrel 21 may have a partial lens barrel fitting part 211 as a partial lens barrel positioning part, and the partial lens barrel 22 may have a partial lens barrel fitting part 221 as a partial lens barrel positioning part. The partial lens barrel fitting parts 211 and 221 can cooperate to align the optical axis of lens 11 and the optical axis of lens 12 when unit 41 and unit 42 are joined together. In this case, the partial lens barrel positioning parts and the partial lens barrel positioning parts may have corresponding shapes, such as a concave shape and a convex shape, and by fitting together, they align the optical axes of the respective lenses.

[0071] Furthermore, as illustrated in Figure 10, in the lens module 100 described above, the partial lens barrel 21 and partial lens barrel 22 may have notches at corresponding positions on their outer surfaces. These notches form a groove that becomes a continuous notch 25 when unit 41 and unit 42 are joined together. Unit 41 and unit 42 can be joined together by a bonding agent, such as an adhesive, supplied to the notch 25.

[0072] Furthermore, the method of joining the units is not limited to the joining method using the notches described above. For example, the lens module 100D can also be obtained by the press-fit joining method illustrated in Figure 17. In this case, the partial lens barrel 21D may have at least one of the press-fit projection 311 and press-fit groove 312 used to join unit 41D and unit 42D. The partial lens barrel 22D may have the other of the press-fit projection 311 and press-fit groove 312 so as to correspond to at least one of the press-fit projection 311 and press-fit groove 312 provided on partial lens barrel 21D.

[0073] Furthermore, the present invention can also constitute an imaging device as illustrated in Figure 18. In this case, the imaging device 1800 comprises an optical system (100, 1803) including the lens module 100 described above, and a housing 1802 enclosing the optical system. The present invention can also constitute an imaging device further comprising an image sensor 1804 that receives light that has passed through the optical system. Such an imaging device 1800 can capture images using the image sensor 1804. Furthermore, if the present invention constitutes a smartphone 1900 as an example of an electronic device, the smartphone 1900 can be used as an imaging device as illustrated in Figure 18, and the smartphone can be an electronic device equipped with a display element that is normally provided in the smartphone to display captured images.

[0074] Furthermore, the present invention can also provide a method for manufacturing the lens module 100, as illustrated in Figure 3. In this case, the manufacturing method includes three steps (steps S301 to S303). Step S301 corresponds to the step of manufacturing at least the unit 41 and unit 42 described above. In this case, step S302 corresponds to the step of positioning the unit 41 and unit 42 so that the optical axis of the lens 11 and the optical axis of the lens 12 are aligned. Step S303 corresponds to the step of joining the positioned unit 41 and unit 42.

[0075] It should be noted that the present invention is not limited to the embodiments described above, and many modifications are possible within the technical concept of the present invention. Furthermore, the effects described in the embodiments are merely a list of the most preferred effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments.

[0076] Furthermore, the embodiments described above can be modified as appropriate without departing from the technical concept. For example, multiple embodiments can be combined. Also, some aspects of at least one embodiment can be deleted or replaced. Also, new aspects can be added to at least one embodiment. Note that the disclosures in this specification include not only those explicitly stated herein, but also all matters that can be understood from this specification and the drawings attached thereto.

[0077] Furthermore, the present invention described above includes the following configuration and method. (Composition 1) A first unit having a first lens made of a first material and a first holder made of a second material different from the first material and holding the first lens, A second unit having a second lens and a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The first material is a resin material that is an acrylic or cyclic olefin polymer, or a glass material. A lens module in which the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together. (Configuration 2) A first unit having a first lens made of a first material and a first holder made of a second material different from the first material and holding the first lens, A second unit having a second lens and a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The coefficient of linear expansion of the first material is between 1 / 5 and 5 times the coefficient of linear expansion of the second material. A lens module in which the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together. (Composition 3) A first unit having a first lens made of a first material and a first holder made of a second material different from the first material and holding the first lens, A second unit having a second lens and a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The second material is an amorphous resin, A lens module in which the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together. (Composition 4) A lens module according to any one of configurations 1 to 3, wherein the glass transition temperature of the first material is lower than the glass transition temperature of the second material. (Composition 5) The second material is a crystalline resin, A lens module according to configuration 1 or 2, wherein the glass transition temperature of the first material is lower than the melting point of the second material. (Composition 6) The coefficients of thermal expansion of the first material and the second material are 2 to 8 × 10⁻⁶. -5 A lens module according to any of configurations 1 to 5, having a temperature of / ℃. (Composition 7) The lens module according to configuration 2 or 3, wherein the first material is polycarbonate, acrylic, or a cyclic olefin polymer. (Composition 8) The lens module according to any one of configurations 1 to 7, wherein the second material is polycarbonate or acrylic. (Composition 9) The lens module according to configuration 1, wherein the first material and the second material are in contact at an interface. (Composition 10) A lens module according to any one of configurations 1 to 9, wherein the first material and the second material are compatible. (Composition 11) The lens module according to any one of configurations 1 to 10, wherein the first unit is a molded body obtained by insert molding the first lens into the first holder. (Composition 12) The lens module according to any one of configurations 1 to 11, wherein the second lens is made of the same material as the first lens, and the second holder is made of the same material as the first holder. (Composition 13) The lens module according to any one of configurations 1 to 12, wherein the first holder and the second holder are made of a light-shielding material. (Composition 14) A lens module according to any one of configurations 1 to 13, wherein at least one of the first lens and the second lens is located between the first holder and the second holder in the optical axis direction. (Composition 15) A lens module according to any one of configurations 1 to 14, wherein at least one of the first holder and the second holder is located between the first lens and the second lens in the optical axis direction. (Composition 16) A lens module according to any one of configurations 1 to 15, wherein the second lens is in contact with the space in contact with the first lens, and a light-shielding member is provided between the first lens and the second lens. (Composition 17) It is further equipped with a third lens and a fourth lens, A lens module according to any one of configurations 1 to 16, wherein the third lens and the fourth lens overlap the first lens and the second lens in the optical axis direction of the lens module. (Composition 18) The lens module according to configuration 17, wherein the first lens and the second lens are positioned between the third lens and the fourth lens. (Composition 19) The third unit comprises a third lens and a third holder made of a different material from the third lens, which holds the third lens. The lens module according to any one of configurations 1 to 16, wherein the second lens and the third lens overlap in the optical axis direction of the lens module, and the second holder and the third holder are fitted together. (Composition 20) The fourth unit comprises a fourth lens and a fourth holder made of a different material from the fourth lens, which holds the fourth lens. The lens module according to configuration 19, wherein the third lens and the fourth lens overlap in the optical axis direction of the lens module, and the third holder is fitted with the fourth holder. (Composition 21) A lens module according to any one of configurations 17 to 20, wherein the second lens is in contact with the space in contact with the first lens, and a light-shielding member is provided between the first lens and the second lens. (Composition 22) A portion of the light-shielding member is located between the first holder and the second holder, as described in configuration 21, in the lens module. (Composition 23) The lens module according to any one of configurations 1 to 22, wherein the first holder and the second holder are in contact with each other. (Composition 24) The lens module according to any one of configurations 1 to 23, wherein the first holder is provided so as to be in contact with the outer circumference of the first lens. (Composition 25) The lens module according to any one of configurations 1 to 24, wherein the first holder has a first groove, the second holder has a second groove, the first groove and the second groove are continuous, and a bonding agent is disposed in the first groove and the second groove. (Composition 26) The first holder has at least one of a press-fit projection and a press-fit groove used to join the first unit and the second unit, The lens module according to any one of configurations 1 to 25, wherein the second holder has the other of the press-fitting projection and the press-fitting groove so as to correspond to at least one of the press-fitting projection and the press-fitting groove. (Composition 27) An optical system including a lens module as described in any of configurations 1 to 26, A housing containing the aforementioned optical system, An optical device equipped with the following features. (Composition 28) An optical system including a lens module as described in any of configurations 1 to 26, An image sensor that receives light that has passed through the optical system, An imaging device equipped with the following features. (Composition 29) An optical system including a lens module as described in any of configurations 1 to 26, An image sensor that receives light that has passed through the optical system, A display element that displays the image captured by the image sensor, Electronic devices equipped with these features. (Composition 30) An optical system including a lens module as described in any of configurations 1 to 26, An image sensor that receives light that has passed through the optical system, A light-emitting element that illuminates the object to be imaged, Electronic devices equipped with these features. (Method 1) A method for manufacturing a unit including a lens and a holder for holding the lens, A method for manufacturing a unit, comprising: installing the holder in a mold; and insert-molding the lens into the holder by pouring a cyclic olefin polymer or acrylic into the mold. [Explanation of Symbols]

[0078] 100...Lens module, 101...Lens barrel, 1...Lens section, 11, 12, 13, 14...Lenses, 21, 22, 23, 24...Partial lens barrel, 25...Notch, 31...Light-shielding member, 41, 42, 43, 44...Holder-integrated lens, 111...Gate, 211, 221, 222...Partial lens barrel fitting section, 21a, 22b...End face, 215...Positioning groove, 224...Mask section, 225...Positioning projection, 311...Press-fit projection, 312...Press-fit groove

Claims

1. A first unit having a first lens made of a first material and a first holder made of a second material different from the first material and holding the first lens, A second unit having a second lens and a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The first material is a resin material that is an acrylic or cyclic olefin polymer, or a glass material. A lens module in which the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together.

2. A first unit having a first lens made of a first material, and a first holder which holds the first lens and is made of a different second material, A second unit having a second lens and a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The coefficient of linear expansion of the first material is 1 / 5 or more and 5 times or less of the coefficient of linear expansion of the second material. A lens module in which the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together.

3. A first unit having a first lens made of a first material and a first holder made of a second material different from the first material and holding the first lens, A second unit having a second lens and a second holder made of a different material from the second lens and holding the second lens, A lens module comprising, The second material is an amorphous resin, A lens module in which the first lens and the second lens overlap in the optical axis direction of the lens module, and the first holder and the second holder are fitted together.

4. The lens module according to any one of claims 1 to 3, wherein the glass transition temperature of the first material is lower than the glass transition temperature of the second material.

5. The second material is a crystalline resin, The lens module according to claim 1 or 2, wherein the glass transition temperature of the first material is lower than the melting point of the second material.

6. The coefficients of thermal expansion of the first material and the second material are 2 to 8 × 10 －５ A lens module according to any one of claims 1 to 3, wherein the temperature is / °C.

7. The lens module according to claim 2 or 3, wherein the first material is polycarbonate, acrylic, or a cyclic olefin polymer.

8. The lens module according to any one of claims 1 to 3, wherein the second material is polycarbonate or acrylic.

9. The lens module according to claim 1, wherein the first material and the second material are in contact at an interface.

10. The lens module according to any one of claims 1 to 3, wherein the first material and the second material are compatible.

11. The lens module according to any one of claims 1 to 3, wherein the first unit is a molded body in which the first lens is insert-molded into the first holder.

12. The lens module according to any one of claims 1 to 3, wherein the second lens is made of the same material as the first lens, and the second holder is made of the same material as the first holder.

13. The lens module according to any one of claims 1 to 3, wherein the first holder and the second holder are made of a light-shielding material.

14. The lens module according to any one of claims 1 to 3, wherein at least one of the first lens and the second lens is located between the first holder and the second holder in the optical axis direction.

15. The lens module according to any one of claims 1 to 3, wherein at least one of the first holder and the second holder is located between the first lens and the second lens in the optical axis direction.

16. The lens module according to any one of claims 1 to 3, wherein the second lens is in contact with the space in contact with the first lens, and a light-shielding member is provided between the first lens and the second lens.

17. It is further equipped with a third lens and a fourth lens, The lens module according to any one of claims 1 to 3, wherein the third lens and the fourth lens overlap the first lens and the second lens in the optical axis direction of the lens module.

18. The lens module according to claim 17, wherein the first lens and the second lens are positioned between the third lens and the fourth lens.

19. The third unit comprises a third lens and a third holder made of a different material from the third lens, which holds the third lens. The lens module according to any one of claims 1 to 3, wherein the second lens and the third lens overlap in the optical axis direction of the lens module, and the second holder and the third holder are fitted together.

20. The fourth unit comprises a fourth lens and a fourth holder made of a different material from the fourth lens, which holds the fourth lens. The lens module according to claim 19, wherein the third lens and the fourth lens overlap in the optical axis direction of the lens module, and the third holder is fitted to the fourth holder.

21. The lens module according to claim 16, wherein a portion of the light-shielding member is located between the first holder and the second holder.

22. The lens module according to any one of claims 1 to 3, wherein the first holder and the second holder are in contact with each other.

23. The lens module according to any one of claims 1 to 3, wherein the first holder is provided so as to be in contact with the outer circumference of the first lens.

24. The lens module according to any one of claims 1 to 3, wherein the first holder has a first groove, the second holder has a second groove, the first groove and the second groove are continuous, and a bonding agent is disposed in the first groove and the second groove.

25. The first holder has at least one of a press-fit projection and a press-fit groove used to join the first unit and the second unit, The lens module according to any one of claims 1 to 3, wherein the second holder has the other of the press-fit projection and the press-fit groove so as to correspond to at least one of the press-fit projection and the press-fit groove.

26. An optical system including a lens module according to any one of claims 1 to 3, A housing containing the aforementioned optical system, An optical device equipped with the following features.

27. An optical system including a lens module according to any one of claims 1 to 3, An image sensor that receives light that has passed through the optical system, An imaging device equipped with the following features.

28. An optical system including a lens module according to any one of claims 1 to 3, An image sensor that receives light that has passed through the optical system, A display element that displays the image captured by the image sensor, Electronic devices equipped with these features.

29. An optical system including a lens module according to any one of claims 1 to 3, An image sensor that receives light that has passed through the optical system, A light-emitting element that illuminates the object to be imaged, Electronic devices equipped with these features.

30. A method for manufacturing a unit including a lens and a holder for holding the lens, A method for manufacturing a unit, comprising: installing the holder in a mold; and insert-molding the lens into the holder by pouring a cyclic olefin polymer or acrylic into the mold.

Images