Optical system device and method for manufacturing optical system device

Abstract

The purpose of the present invention is to provide an optical system device and a method for manufacturing the optical system device, capable of preventing or suppressing an adhesive from bleeding into an uneven shape of an optical element.　The optical system device includes: an optical element having an uneven shape that exhibits an optical function; and a housing that holds the optical element on a contact surface. In the optical element, at least the uneven shape is formed of an elastic resin member, and a space between the optical element and the contact surface of the housing is sealed with the elastic resin member.

Description

Optical system device and method for manufacturing an optical system device

[0001] The present invention relates to an optical system device and a method for manufacturing the optical system device.

[0002] A three-dimensional measurement optical system using the time-of-flight (TOF) method is being adopted in mobile devices, automobiles, robots, etc. This measures the distance of an object from the time it takes for the light irradiated from a light source to be reflected back after hitting the object. If the light from the light source irradiates a predetermined area of the object, the distance at each irradiated point can be measured, and the three-dimensional structure of the object can be detected.

[0003] The above system consists of a light irradiation means for irradiating light, an optical element for controlling the light of the light irradiation means into a predetermined light distribution, a camera unit for detecting the light reflected from each point of the object, and an arithmetic unit for calculating the distance of the object from the signal received by the camera unit. Since existing VCSELs, CMOS imagers, CPUs, etc. can be used for the light irradiation means, camera unit, and arithmetic unit, the unique part of the above system is the optical element.

[0004] The optical element requires alignment in relation to the light irradiation means (light source). Conventionally, the light irradiation means and the optical element were arranged in a housing and fixed with an adhesive (for example, Patent Document 1).

[0005] International Publication No. 2023 / 090435

[0006] Here, the optical element has a concavo-convex shape consisting of a plurality of convex and concave portions to control the light distribution of light. Also, the optical element is formed by cutting a sheet or substrate having the concavo-convex shape using a molding technique such as nanoimprint into a predetermined size and then used. Therefore, if an adhesive is applied and fixed to the contact portion between the housing and the optical element, there is a problem that the adhesive may seep into the concave portion of the optical element due to capillary action, damaging the function of the concavo-convex shape. To avoid this, there is also a method of not providing a concavo-convex shape at the portion where the optical element contacts the housing. However, in this case, since the size of the area of the concavo-convex shape is determined, there is a problem that an optical element of a predetermined size cannot be freely cut from the sheet, resulting in low versatility.

[0007] Therefore, the present invention aims to provide an optical system device and a method for manufacturing the optical system device that can prevent or suppress the seepage of adhesive into the uneven shape of an optical element.

[0008] To achieve the above objective, the present invention provides an optical system comprising an optical element having an uneven shape that exhibits optical function, and a housing that holds the optical element at a contact surface, wherein at least the uneven shape of the optical element is formed from an elastic resin member, and the space between the optical element and the contact surface of the housing is sealed by the elastic resin member.

[0009] In this case, it is preferable that the optical element is fixed to the housing with adhesive outside the portion that is in contact with the contact surface.

[0010] Furthermore, it is preferable that the optical element is fixed to the housing in a position where the contact surface is pressed into the elastic resin member beyond the position of the recess of the uneven shape. In this case, the elastic resin member can be made of silicone rubber.

[0011] Furthermore, the housing has an XY reference portion that serves as a reference for the position of the optical element in the X and Y directions perpendicular to the Z direction, and it is preferable that the side surface of the optical element and the XY reference portion are in contact.

[0012] The housing may also be fixed to the optical element and include a light irradiation means for irradiating the optical element with light.

[0013] Furthermore, the present invention relates to a method for manufacturing an optical system comprising an optical element having an uneven shape that exhibits optical functions and a housing that holds the optical element at a contact surface, wherein at least the uneven shape of the optical element is formed from an elastic resin member, and the method includes an optical element fixing step in which the space between the optical element and the contact surface of the housing is sealed with the elastic resin member.

[0014] In this case, it is preferable that the optical element fixing step involves fixing the optical element to the housing with an adhesive outside the portion that is in contact with the contact surface.

[0015] Furthermore, the optical element fixing step is preferable in which the optical element is fixed to the housing while under pressure until the contact surface is pushed into the elastic resin member beyond the position of the recess of the uneven shape. In this case, the elastic resin member can be made of silicone rubber.

[0016] Furthermore, it is preferable that the housing has an XY reference portion which serves as a reference for the position of the optical element in the X and Y directions perpendicular to the Z direction, the side surface of the optical element and the XY reference portion are in contact, and that there is an XY direction positioning step for positioning the optical element at a predetermined position in the housing.

[0017] The device may also include a step for attaching a light irradiation means to the housing for irradiating the optical element with light.

[0018] The optical system and its manufacturing method of the present invention seal the contact area between the optical element and the housing with an elastic resin member, thereby preventing or suppressing the adhesive from seeping into the uneven shape of the optical element.

[0019] These are (a) a plan view, (b) a longitudinal cross-sectional view along line A-A, and (c) a bottom view of the housing according to the present invention. These are exploded view diagrams of the optical system according to the present invention. These are longitudinal cross-sectional views and partially enlarged views of the optical system according to the present invention. These are (a) a plan view, (b) a longitudinal cross-sectional view, and (c) a bottom view of the optical system according to the present invention. This diagram shows the process of attaching the light irradiation means according to the manufacturing method of the optical system according to the present invention. This diagram shows the process of attaching the optical element according to the manufacturing method of the optical system according to the present invention. This is a longitudinal cross-sectional view of the jig according to the present invention.

[0020] The optical system 100 of the present invention will be described below with reference to Figures 1 to 6. However, the present invention is not intended to be limited to these embodiments only. In addition, in describing the embodiments described later, the same reference numerals are used for the same components as in the embodiments described above, and redundant explanations are omitted.

[0021] As shown in Figures 2 to 4, the optical system 100 of the present invention mainly consists of an optical element 3 and a housing 2 that holds the optical element 3 on a contact surface 27. The optical system 100 may also have a light irradiation means 1 fixed to the housing 2 for irradiating the optical element 3 with light. In this case, the housing 2 holds the light irradiation means 1 so that its optical axis is oriented in the Z direction. In Figure 3, the optical system 100 is configured to include a housing 2, an optical element 3 provided on the upper side of the housing 2, and a light irradiation means 1 provided on the lower side of the housing 2. The Z direction can be any direction as long as it coincides with the optical axis direction of the light irradiation means 1, but in Figure 3, the upward direction in the figure is defined as the Z direction.

[0022] [Housing 2] As shown in Figure 1, housing 2 has an optical element set section 26 for arranging the optical element 3. Housing 2 may also further have a light irradiation means set section 21 for arranging the light irradiation means 1. Housing 2 may be made of any conventionally known material, for example, a heat-resistant resin material or ceramics can be used.

[0023] The optical element set section 26 has a contact surface 27 for holding the optical element 3. By bringing the optical element 3 into contact with the contact surface 27, the optical element 3 can be fixed so that its surface (the surface with the uneven shape 31) is perpendicular to the Z direction. The contact surface 27 is formed at a predetermined position in the Z direction from the Z reference section 22, which is the reference for the Z direction position of the housing. Therefore, by fixing the optical element 3 to the contact surface 27, the optical element 3 can be fixed at a predetermined position in the Z direction from the Z reference section 22. Note that the shape of the contact surface 27 is not limited to a planar shape, but may be a three-dimensional shape such as a curved surface. For example, a three-dimensional shape such as a convex shape that facilitates sealing between the optical element 3 and the housing 2 can be formed on a part of the contact surface 27. The position of the contact surface 27 in the Z direction relative to the Z reference section is sufficient as long as it is clear, but preferably, as shown in Figure 3, the contact surface 27 itself is the Z reference section 22. The optical element set section 26 can have any shape as long as it has a contact surface 27, but for example, it can be a concave shape with a space on the upper side of the housing 2 that can house part or all of the optical element 3. In this case, the space is formed to be wider in the X and Y directions than the optical element 3 so that it can house the optical element 3. Alternatively, the optical element set section 26 may have only a contact surface 27 for placing the optical element 3 on the upper end of the housing 2.

[0024] Furthermore, the optical element set section 26 may have an XY reference section 28 that serves as a reference for the position of the optical element 3 in the X and Y directions perpendicular to the Z direction. This allows the optical element 3 to be positioned in the X and Y directions relative to the XY reference section 28 if the side surface of the optical element 3 is in contact with the XY reference section 28. While it is preferable for the X and Y directions to be perpendicular to each other, the X and Y directions are not necessarily parallel. The XY reference section 28 can be composed of, for example, an X reference section 28x that contacts the side surface of the optical element 3 perpendicular to the X direction, and a Y reference section 28y that contacts the side surface of the optical element 3 perpendicular to the Y direction. The XY reference section 28, such as the X reference section 28x and the Y reference section 28y, is formed in a convex shape on the inner wall of the optical element set section 26.

[0025] Furthermore, the light irradiation means set section 21 is for forming a position adjustment space 23 for determining the position of the light irradiation means 1 in the Z direction relative to the Z reference section 22. The position adjustment space 23 has a predetermined width in the Z direction, and the position of the light irradiation means 1 in the Z direction can be adjusted within this width range. Specifically, the light irradiation means set section 21 is formed in a cylindrical shape on the lower side of the housing 2, and the light irradiation means 1 can be set in the position adjustment space 23 so as to enclose it. Also, the position adjustment space 23 is formed to be wider in the X and Y directions than the light irradiation means 1 so as to accommodate the light irradiation means 1. The light irradiation means 1 is fixed within the position adjustment space 23 of the light irradiation means set section 21 without contacting the housing in the Z direction. By configuring the light irradiation means set section 21 in this way, even if the distance between the light irradiation means 1 and the optical element 3 changes due to design changes, etc., the position of the light irradiation means 1 can be adjusted by the position adjustment space 23, so the same housing can be used.

[0026] The Z-reference section 22 is a reference part for determining the position of the light irradiation means 1 in the Z direction relative to the housing 2. By positioning the light irradiation means 1 with respect to the Z-reference section 22, the distance in the Z direction from the optical element 3 fixed to the housing 2 can be precisely adjusted. The Z-reference section 22 can be anything as long as it serves as a reference for the position of the light irradiation means 1 in the Z direction, but for example, it is formed as a plane perpendicular to the Z direction of the housing 2.

[0027] Furthermore, the light irradiation means set section 21 may have an XY reference section 24 that serves as a reference for the position of the light irradiation means 1 in the X and Y directions perpendicular to the Z direction. This allows the light irradiation means 1 to be positioned in the X and Y directions relative to the XY reference section 24 when the side surface of the light irradiation means 1 is in contact with the XY reference section 24. While it is preferable for the X and Y directions to be perpendicular to each other, this is not the only limitation as long as the X and Y directions are parallel to each other. The XY reference section 24 can be composed of, for example, an X reference section 24x that contacts the side surface of the substrate 12 of the light irradiation means 1 perpendicular to the X direction, and a Y reference section 24y that contacts the side surface of the substrate 12 of the light irradiation means 1 perpendicular to the Y direction. The XY reference section 24, such as the X reference section 24x and the Y reference section 24y, is formed, for example, in a convex shape on the inner wall of the light irradiation means set section 21.

[0028] Furthermore, as shown in Figure 3(a), the light irradiation means set section 21 is connected to the optical element set section 26 by an intermediate section 29. The intermediate section 29 also has a space 291 that penetrates from the light irradiation means set section 21 to the optical element set section 26. The space 291 is sized so as not to obstruct the light from the light irradiation means 1 irradiating the optical element 3. Note that, as shown in Figure 3(b), if the shape of the space 291 and the position adjustment space 23 in the XY plane are the same, the intermediate section 29 may be integrated with the light irradiation means set section 21 and indistinguishable. This is preferable because it allows for a larger width in the Z direction of the position adjustment space 23.

[0029] [Optical element 3] The optical element 3 has a concave / concave shape 31 that exhibits an optical function. The concave / concave shape 31 can be any shape that can exhibit an optical function such as light distribution control. For example, a microlens array (MLA), a diffractive optical element (DOE), a metalens, etc., is suitable as a shape that can control and emit light incident from the light irradiation means 1. The lenses of the microlens array may be arranged periodically or randomly. Furthermore, the concave / concave shape 31 can be controlled in any way according to the application, as long as it controls the light from the light irradiation means 1 and exhibits an optical function. For example, the concave / concave shape may illuminate the entire irradiation area with a predetermined light distribution, illuminate in a dot pattern, or illuminate in a line pattern.

[0030] Furthermore, the optical element 3 has at least one uneven surface 31 formed from an elastic resin member 34. This ensures that when the optical element 3 and the housing 2 are pressurized, the contact surface 27 between the optical element 3 and the housing 2 is sealed by the elastic resin member 34. The elastic resin member 34 can be any resin with sufficient elasticity to seal the contact surface 27 between the optical element 3 and the housing 2; for example, silicone rubber such as polydimethylsiloxane (PDMS) can be used. The optical element 3, as shown in Figure 3, for example, consists of an optical element body 32 made of glass or resin, and an elastic resin member 34 having an uneven surface 31 on the surface 321 of the optical element body 32. Alternatively, the optical element 3 may be formed integrally from the same material as the optical element body 32 and the elastic resin member 34.

[0031] Furthermore, the optical element 3 is fixed in contact with a contact surface 27 formed on the optical element set portion 26 of the housing 2. The optical element 3 may be fixed to the optical element set portion 26 of the housing 2 in any way, but for example, as shown in Figures 4(a) and (b), it is fixed with adhesive 5. Here, as shown in Figure 3, the uneven shape 31 has a plurality of convex portions 31a arranged in a row, and the spaces between these convex portions 31a are recesses 31b. Therefore, when liquid adhesive 5 is applied to the contact surface 27, there is a problem that the adhesive 5 tends to seep into the recesses 31b of the optical element 3 by capillary action when fixing the optical element 3. Accordingly, it is preferable that the optical element 3 is fixed to the housing 2 with adhesive 5 on the outside of the part that is in contact with the contact surface 27 (the outer edge of the optical element 3 or the optical element body 32 side) in order to prevent or suppress the application of adhesive 5 to the contact surface 27 that may come into contact with the uneven shape 31. In this case, if the elastic resin member 34 is used as a seal, the space between the optical element 3 and the contact surface 27 of the housing 2 can be sealed with the elastic resin member 34, thereby preventing or suppressing the seepage of the adhesive 5 into the recess 31b. In this case, as shown in Figure 3, it is preferable that the optical element 3 is fixed to the housing 2 in a position where the contact surface 27 is pushed into the elastic resin member beyond the position of the recess 31b of the uneven shape 31. This ensures that even when the uneven shape 31 of the optical element 3 is in contact with the contact surface 27, the recess 31b is reliably crushed, sealing the space between the optical element 3 and the contact surface 27 of the housing 2.

[0032] [Light Irradiation Means 1] Light irradiation means 1 mainly consists of a light source unit 11 and a substrate 12 that holds the light source unit 11. Light irradiation means 1 is fixed to the light irradiation means set section 21 of the housing 2. Light irradiation means 1 may be fixed to the light irradiation means set section 21 of the housing 2 in any way, but for example, as shown in Figures 4(b) and (c), it is fixed with adhesive 4.

[0033] Specifically, the light source unit 11 is for irradiating the optical element 3 with light of a predetermined wavelength. The light source unit 11 can be any device that has a light source for irradiating the optical element 3 with light. The light source unit 11 may be a single light source or multiple light sources. Alternatively, multiple light sources may be created by passing the light from a single light source through an aperture in which multiple pores are formed. When the light source unit 11 is composed of multiple light sources, it is preferable to form the light-emitting surfaces of each light source on the same plane. The position of the light-emitting surface of the light source in the Z direction is set as the irradiation means reference position 15, which is the position of the light irradiation means 1 in the Z direction. A specific example of the light source unit 11 is, for example, a VCSEL (Vertical Cavity Surface Emitting Laser) which can be expected to produce high output with low power. A VCSEL has multiple light sources that can irradiate light in a direction perpendicular to the light-emitting surface. It is also preferable that a light-absorbing film is formed on parts other than the light sources to prevent noise from reflected light.

[0034] The substrate 12 holds the light source unit 11 in a predetermined direction, for example, so that the optical axis of the light source unit 11 faces the Z direction. If the light source unit 11 has multiple light sources, the substrate 12 is arranged so that the arrangement direction of the light source units 11 faces a specific direction on the substrate 12. The substrate 12 also has an irradiation means side fixing portion 13 on its side, which is fixed to the light irradiation means set portion 21 of the housing 2 with adhesive 4 or the like. The substrate 12 is formed to be larger than the width of the light source unit 11 in the X and Y directions, and smaller than the width of the opening of the position adjustment space 23 in the X and Y directions. The substrate 12 can be made of any material that can hold the light source unit 11 and can be fixed to the housing 2 with adhesive 4 or the like. For example, a heat-resistant resin or ceramic can be used.

[0035] Next, the manufacturing method of the optical system 100 will be described. The manufacturing method of the optical system 100 is divided into a light irradiation means mounting step (see Figure 5) and an optical element mounting step (see Figure 6). The light irradiation means mounting step mainly consists of a holding step, a Z-direction arrangement step, and a light irradiation means fixing step, and is for mounting the light irradiation means 1 to the housing 2. In addition, the light irradiation means mounting step may further include an XY-direction arrangement step before the light irradiation means fixing step. The optical element mounting step includes at least an optical element fixing step and is for mounting the optical element 3 to the housing 2.

[0036] [Light Irradiation Means Installation Process] In the light irradiation means installation process, the light irradiation means 1 is attached to the housing 2 using a jig 8. In Figure 5, the left-hand diagrams are partial cross-sectional front views, and the right-hand diagrams are plan views corresponding to the left-hand diagrams, excluding the jig 8. Note that the drive mechanism and control mechanism that drive the jig 8 are not shown and their descriptions are omitted.

[0037] [Jig 8] Jig 8 is a spacing adjustment tool used to attach the light irradiation means 1 to the housing 2. As shown in Figure 7, jig 8 has a holding portion 81 for holding the light irradiation means 1 and a contact portion 82 formed at a predetermined distance Ph away from the holding portion 81. Specifically, jig 8 has a convex shape with a narrow portion 83 on the upper side and a wider portion 84 on the lower side that is wider than the narrow portion 83. The holding portion 81 is formed at the top of the jig 8 on the narrow portion 83 side. Therefore, the narrow portion 83 is formed to be narrower than the width of the position adjustment space 23 so that it can pass through the position adjustment space 23 of the light irradiation means set portion 21. The contact portion 82 is formed at the shoulder portion that connects the narrow portion 83 and the wide portion 84 at the point where it contacts the Z reference portion 22 of the housing 2. Therefore, the wide portion 84 is formed to be wide enough to contact the Z reference portion 22 of the housing 2. Furthermore, the holding portion 81 of the narrow portion 83 is formed such that when the light irradiation means 1 is held, the irradiation means reference position 15 of the light irradiation means 1 is located at a predetermined distance Ph in the Z direction from the contact portion 82. For example, when the irradiation means reference position 15 of the light irradiation means 1 is held by the holding portion 81, the holding portion 81 is formed at a predetermined distance Ph in the Z direction from the contact portion 82. When the surface of the substrate 12 of the light irradiation means 1 is held by the holding portion 81, the holding portion 81 is formed at a predetermined distance Ph + Sh in the Z direction from the contact portion 82. Here, Sh represents the distance in the Z direction between the surface of the substrate 12 of the light irradiation means 1 and the irradiation means reference position 15. The jig 8 may also have a suction hole 85 that penetrates through the center to the holding portion 81 in the Z direction. This allows the light irradiation means 1 to be reliably adsorbed and held to the holding portion 81 by the suction action of the suction hole 85. Furthermore, the jig 8 should preferably be movable in at least the Z direction, and more preferably, it should be formed to be movable in the X and Y directions as well. A well-known drive mechanism and control mechanism for driving the jig 8 may be used.

[0038] [Holding Process] The holding process is the process of holding the light irradiation means 1 in the jig 8 described above. Specifically, as shown in Figure 5(a), the light irradiation means 1, which is placed in the light irradiation means set section 21 with the irradiation means reference position 15 facing downwards, is placed on the holding section 81 of the jig 8. Alternatively, if a housing is used in which the light irradiation means set section 21 and the intermediate section 29 are integrated, as shown in Figure 3(b), the light irradiation means 1 with the irradiation means reference position 15 facing downwards may be placed on the holding section 81 of the jig 8 and moved from the optical element set section 26 side through the space 291 inside the housing to the position adjustment space 23. The light irradiation means 1 held in the jig 8 in this way is held so that its irradiation means reference position 15 is at a predetermined distance Ph in the Z direction from the contact section 82. If the jig 8 has a suction hole 85, the light irradiation means 1 may be held in the holding section 81 by suction using the suction hole 85.

[0039] [XY Direction Arrangement Process] The XY direction arrangement process involves bringing the side surface of the light irradiation means 1 into contact with the XY reference section 24 and positioning the light irradiation means 1 in a predetermined location within the light irradiation means set section 21. Specifically, as shown in Figure 5(b), with a gap between the contact section 82 and the Z reference section 22, the housing 2 or jig 8 is moved in the X direction, bringing the X-side surface of the substrate 12 of the light irradiation means 1 into contact with the X reference section 24x of the XY reference section 24. Next, the housing 2 or jig 8 is moved in the Y direction, bringing the Y-side surface of the substrate 12 of the light irradiation means 1 into contact with the Y reference section 24y of the XY reference section 24. This allows the housing 2 and the light irradiation means 1 to be positioned in the X and Y directions.

[0040] [Z-direction positioning process] The Z-direction positioning process involves bringing the contact portion 82 and the Z-reference portion 22 into contact with the housing 2 and positioning the light irradiation means 1 at a predetermined position within the light irradiation means set portion 21. Specifically, as shown in Figure 5(c), the housing 2 or jig 8 is moved in the Z direction, and the narrow portion 83 of the jig 8 and the light irradiation means 1 held by the holding portion 81 of the narrow portion 83 are passed through to the position adjustment space 23 of the housing 2, bringing the contact portion 82 and the Z-reference portion 22 into contact. As a result, the contact portion 82 and the Z-reference portion 22 come into contact and are at the same position, so the irradiation means reference position 15 of the light irradiation means 1 held by the holding portion 81 is positioned at a predetermined position at a predetermined distance Ph away from the Z-reference portion 22. Therefore, the Z-direction positioning of the housing 2 and the light irradiation means 1 can be performed. Note that the Z-direction positioning process may be performed before the XY-direction positioning process. In this case, with the contact portion 82 of the jig 8 in contact with the Z-reference portion 22 of the housing 2, the housing 2 is moved in the X and Y directions, so that the X side of the light irradiation means 1 comes into contact with the X-reference portion 24x and the Y-side surface comes into contact with the Y-reference portion 24y. The Z-direction positioning step may also be performed before the holding step. In this case, with the contact portion 82 of the jig 8 in contact with the Z-reference portion 22 of the housing 2, the light irradiation means 1 is placed on the holding portion 81 of the jig 8.

[0041] [Light Irradiation Means Fixing Process] The light irradiation means fixing process involves fixing the light irradiation means 1 in a predetermined position on the housing 2. Any method is acceptable for fixing the light irradiation means 1 to the housing 2 as long as it can be fixed in the predetermined position, but for example, as shown in Figure 5(d), it can be fixed with adhesive 4. Specifically, adhesive 4 is injected into the gap between the irradiation means side fixing location 13 on the substrate 12 of the light irradiation means 1 and the light irradiation means set part 21, thereby bonding and fixing the light irradiation means 1 to the housing 2. Once the adhesive 4 has hardened, the suction at the suction hole 85 of the jig 8 is stopped, and the light irradiation means 1 is removed from the jig 8. As a result, the irradiation means reference position 15 of the light irradiation means 1 is fixed in a predetermined position at a predetermined distance Ph away from the Z reference part 22.

[0042] In addition, as long as the adhesive 4 can firmly bond the light irradiation means 1 and the housing 2, any type of adhesive can be used. For example, as the adhesive 4, an epoxy-based adhesive, an acrylic-based adhesive, a cyanoacrylate-based adhesive, a silicone-based adhesive, or a resin adhesive of a mixed system thereof can be used. In particular, it is preferable to use an ultraviolet curable type or a combination of light and heat curable type adhesive because it has high productivity and can suppress the thermal influence on the optical element.

[0043] [Optical Element Mounting Step] In the optical element mounting step, the optical element 3 is mounted on the housing 2 using the jig 9. In FIG. 6, each left-side figure is a partial cross-sectional front view, and the right-side figures are plan views corresponding to the left-side figures excluding the jig. Note that the drive mechanism for driving the jig and the control mechanism for controlling it, etc., are not shown and the description is omitted.

[0044] [Jig 9] The jig 9 is a tool used to mount the optical element 3 on the housing 2. As shown in FIG. 6, the jig 9 has a jig body and a holding portion 91 for holding the optical element 3. Further, the jig 9 may have a suction hole 95 that penetrates in the Z direction to the holding portion 91 at the center. Thereby, the optical element 3 can be reliably adsorbed and held in the holding portion 91 by the suction operation of the suction hole 95. Also, the jig 9 is preferably movable at least in the Z direction, and more preferably, it is formed to be movable in the X direction and the Y direction as well. A well-known drive mechanism for driving the jig 9 and a control mechanism for controlling it may be used. Note that the jig 8 for holding the light irradiation means 1 can also be used as the jig 9.

[0045] [Holding Step] The holding step is a step of holding the optical element 3 by the above-described jig 9. Specifically, as shown in FIG. 6(a), the back surface of the optical element 3 with the elastic resin member 34 facing the housing 2 side is held by the holding portion 91 of the jig 9. When the jig 9 has the suction hole 95, the optical element 3 may be held in the holding portion 91 by suction using the suction hole 95.

[0046] [Z-direction positioning process] The Z-direction positioning process is a process in which the contact surface 27 of the housing 2 and the elastic resin member 34 of the optical element 3 come into contact, and the optical element 3 is positioned in a predetermined position in the optical element set section 26. Since the contact surface 27 is formed in a predetermined position in the Z direction with reference to the Z reference section 22, the optical element 3 held by the holding section 91 and the light irradiation means 1 fixed to the housing 2 are positioned at predetermined positions separated by a predetermined distance Ph. Therefore, the Z-direction positioning of the light irradiation means 1 fixed to the housing 2 and the optical element 3 can be performed.

[0047] [XY Direction Arrangement Process] The XY direction arrangement process involves bringing the side surface of the optical element 3 into contact with the XY reference section 28 and positioning the optical element 3 in a predetermined location on the optical element set section 26. Specifically, as shown in Figure 6(a), first, the housing 2 to which the light irradiation means 1 was attached in the light irradiation means attachment process is placed with the optical element set section 26 facing upwards. Next, as shown in Figure 6(b), the housing 2 or jig 9 is moved in the Z direction to bring the contact surface 27 of the housing 2 into light contact with the elastic resin member 34 of the optical element 3. In this state, as shown in Figure 6(c), the housing 2 or jig 9 is moved in the X direction to bring the X-side surface of the optical element 3 into contact with the X reference section 28x of the XY reference section 28. Also, the housing 2 or jig 8 is moved in the Y direction to bring the side surface of the optical element 3 into contact with the Y reference section 28y of the XY reference section 28. This allows for the positioning of the housing 2 and the optical element 3 in the X and Y directions. Note that the XY direction arrangement process may be performed before the Z direction arrangement process. In this case, the side surface of the optical element 3 and the XY reference section 28 are in contact, and the contact surface 27 of the housing 2 and the elastic resin member 34 of the optical element 3 are brought into contact.

[0048] [Optical Element Fixing Process] The optical element fixing process involves fixing the optical element 3 to the housing while it is in contact with the contact surface 27. Any method is acceptable for fixing the optical element 3 to the housing 2 as long as it can be fixed while the optical element 3 is in contact with the contact surface 27, but for example, as shown in Figure 6(d), it can be fixed with adhesive 5. However, if the adhesive 5 comes into contact with the uneven shape 31 of the optical element 3 before it hardens, there is a risk that the recesses 31b of the uneven shape 31 may be filled due to capillary action, etc. Therefore, it is preferable to fix the optical element 3 to the housing 2 with adhesive 5 on the outside of the part that is in contact with the contact surface 27 (the outer edge of the optical element 3 or the optical element body 32 side) in order to prevent or suppress the application of adhesive 5 to the contact surface 27 that may come into contact with the uneven shape 31. Here, since at least the surface of the optical element 3 on the side facing the light irradiation means 1 is formed of an elastic resin member 34, the elastic resin member 34 can be used as a seal, and the optical element 3 and the contact surface 27 of the housing 2 can be sealed with the elastic resin member 34 and then fixed with adhesive 5. Specifically, the contact surface 27 of the housing 2 and the elastic resin member 34 of the optical element 3 are pressurized, and the optical element 3 is moved a predetermined distance in the Z direction relative to the housing 2 to seal the space between the housing 2 and the optical element 3. Then, adhesive 5 can be injected into the corner between the contact surface 27 of the housing 2 and the side surface of the optical element 3 and allowed to solidify. Furthermore, if the surface of the elastic resin member 34 that contacts the contact surface 27 has an uneven shape 31, it is better to pressurize it until the recesses 31b of the uneven shape 31 are completely crushed before fixing it with adhesive 5. To explain using the position of the recess 31b of the uneven shape 31 that is not in contact with the contact surface 27, the recess 31b should be fixed with adhesive 5 while under pressure until the position of the recess 31b exceeds the position of the contact surface 27 towards the light irradiation means. This ensures that even if the uneven shape 31 of the optical element 3 is large enough to contact the contact surface 27, the recess 31b is reliably crushed, sealing the space between the optical element 3 and the contact surface 27 of the housing 2. When pressurizing the contact surface 27 of the housing 2 and the elastic resin member 34 of the optical element 3, the optical element 3 moves a distance Kh in the Z direction relative to the housing 2 due to the pressurization. Therefore, in the Z-direction arrangement step of the light irradiation means mounting step, care should be taken to consider this distance Kh when arranging the light irradiation means 1 in a predetermined position within the light irradiation means set section 21.Finally, when the adhesive 5 has cured, stop the suction at the suction hole 95 of the jig 9 and remove the optical element 3 from the jig 9. As a result, the optical element 3 is fixed at a predetermined position that is at a distance Ph away from the irradiation means reference position 15 of the light irradiation means 1.

[0049] Note that any adhesive can be used as the adhesive 5 as long as it can securely bond the optical element 3 and the housing 2. For example, as the adhesive 5, an epoxy-based adhesive, an acrylic-based adhesive, a cyanoacrylate-based adhesive, a silicone-based adhesive, or a resin adhesive of a mixed system thereof can be used. In particular, it is preferable to use an ultraviolet-curable or photo-thermo dual-curable adhesive because it has high productivity and can suppress the thermal influence on the optical element.

[0050] 1: Light irradiation means 2: Housing 27: Contact surface 28: XY reference portion (for optical element) 3: Optical element 31: Concavo-convex shape 31b: Concave portion 34: Elastic resin member 5: Adhesive 100: Optical system device

Claims

1. An optical system comprising an optical element having an uneven shape that exhibits optical functions, and a housing that holds the optical element at a contact surface, wherein at least the uneven shape of the optical element is formed from an elastic resin material, and the space between the optical element and the contact surface of the housing is sealed by the elastic resin material.

2. The optical system according to claim 1, characterized in that the optical element is fixed to the housing with an adhesive outside the portion that is in contact with the contact surface.

3. The optical system according to claim 1, characterized in that the optical element is fixed to the housing in a position where the contact surface is pressed into the elastic resin member beyond the position of the recess of the uneven shape.

4. The optical system according to any one of claims 1 to 3, characterized in that the elastic resin member is made of silicone rubber.

5. The optical system according to any one of claims 1 to 3, characterized in that the housing has an XY reference portion which serves as a reference for the position of the optical element in the X and Y directions perpendicular to the Z direction, and the side surface of the optical element and the XY reference portion are in contact.

6. The optical system according to any one of claims 1 to 3, characterized in that it comprises a light irradiation means fixed to the housing for irradiating light onto the optical element.

7. A method for manufacturing an optical system comprising an optical element having an uneven shape that exhibits optical functions and a housing that holds the optical element at a contact surface, wherein at least the uneven shape of the optical element is formed from an elastic resin material, and the method for manufacturing an optical system comprises an optical element fixing step of sealing the space between the optical element and the contact surface of the housing with the elastic resin material.

8. The method for manufacturing an optical system according to claim 7, characterized in that the optical element fixing step involves fixing the optical element with an adhesive to the housing outside the portion that is in contact with the contact surface.

9. The method for manufacturing an optical system according to claim 7 or 8, characterized in that the optical element fixing step involves fixing the optical element to the housing while applying pressure until the contact surface is pushed into the elastic resin member beyond the position of the recess of the uneven shape.

10. The method for manufacturing an optical system according to claim 7 or 8, characterized in that the elastic resin member is made of silicone rubber.

11. The method for manufacturing an optical system according to claim 7 or 8, characterized in that the housing has an XY reference portion which serves as a reference for the position of the optical element in the X and Y directions perpendicular to the Z direction, the side surface of the optical element and the XY reference portion are in contact, and the method for manufacturing an optical system according to claim 7 or 8, comprising an XY direction arrangement step of arranging the optical element at a predetermined position in the housing.

12. A method for manufacturing an optical system according to claim 7 or 8, characterized by having a step for attaching a light irradiation means to a housing for irradiating light onto the optical element.

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