Optical system device and method for manufacturing optical system device

Abstract

The purpose of the present invention is to provide an optical system device capable of easily adjusting, without changing the housing, a clearance between a light irradiation means and an optical element even when a combination of the light irradiation means and the optical element is changed, and a method for manufacturing the same.　An optical system device 100 comprises: a light irradiation means 1; and a housing 2 that holds the light irradiation means 1 with the optical axis directed in the Z direction, wherein the housing 2 includes: a Z reference part 22 that serves as the reference of the position of the light irradiation means 1 in the Z direction; and a light-irradiation-means setting part 21 that forms a position adjustment space 23 for determining the position of the light irradiation means 1 with respect to the Z reference part 22 in the Z direction, and the light irradiation means 1 has a structure that is fixed without abutting on the housing 2 in the Z direction in the position adjustment space 23. The optical system device 100 is manufactured by: a holding step for holding the light irradiation means 1 on a holding part 81 of a jig 8; a Z-direction arrangement step for bringing a contact part 82 of the jig 8 into contact with the Z reference part 22 of the housing 2 and placing the light irradiation means 1 at a predetermined position in the light-irradiation-means setting part 21; and a first fixing step for fixing the light irradiation means 1 at a predetermined position of the housing 2.

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. 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] In the above system, an optical system device including a light irradiation means (light source) for irradiating light and an optical element for controlling the light distribution, etc. of the light is essential. Also, in the optical system device, there may be cases where the light irradiation means and the optical element must be accurately arranged at a predetermined distance apart. Conventionally, in order to adjust the predetermined distance, when fixing an optical element or a light irradiation means to a housing with an adhesive, there has been a method of adjusting with the thickness of the adhesive (for example, Patent Document 1).

[0004] International Publication No. 2023 / 090435

[0005] However, the conventional one has a problem that if there is a change in the combination of the light irradiation means and the optical element, and the predetermined distance for separating the light irradiation means and the optical element becomes too large or too small to exceed the thickness of the adhesive, it is necessary to redesign the housing itself. Therefore, an object of the present invention is to provide an optical system device and a method for manufacturing an optical system device that can easily adjust the distance for separating the light irradiation means and the optical element without changing the housing even if there is a change in the combination of the light irradiation means and the optical element.

[0006] To achieve the above objective, the present invention provides an optical system comprising a light irradiation means capable of irradiating light and a housing that holds the light irradiation means such that its optical axis faces the Z direction, wherein the housing has a Z reference portion that serves as a reference for the position of the light irradiation means in the Z direction and a light irradiation means set portion that forms a position adjustment space for determining the position of the light irradiation means in the Z direction with respect to the Z reference portion, and the light irradiation means is fixed within the position adjustment space without contact with the housing in the Z direction.

[0007] In this case, the light irradiation means set portion has an XY reference portion that serves as a reference for the position of the light irradiation means in the X and Y directions perpendicular to the Z direction, and it is preferable that the side surface of the light irradiation means and the XY reference portion are in contact.

[0008] The light irradiation means may be fixed to the light irradiation means set portion of the housing with an adhesive.

[0009] Furthermore, the optical system of the present invention comprises an optical element having an uneven shape that exhibits optical functions, and the housing has an optical element set portion having a contact surface formed at a predetermined position in the Z direction with reference to the Z reference portion, and the optical element may be fixed in contact with the contact surface.

[0010] Furthermore, the optical element may be fixed to the housing with adhesive outside the portion that is in contact with the contact surface.

[0011] Furthermore, the optical element is formed from an elastic resin member having the uneven shape on at least the surface on the light irradiation means side, and the space between the optical element and the contact surface of the housing may be sealed with the elastic resin member.

[0012] Furthermore, it is preferable that the recesses of the uneven shape of the optical element are located on the light irradiation means side of the contact surface.

[0013] Furthermore, the present invention relates to a method for manufacturing an optical system comprising a light irradiation means capable of irradiating light and a housing that holds the light irradiation means such that its optical axis faces the Z direction, wherein the housing has a Z reference portion that serves as a reference for the position of the light irradiation means in the Z direction and a light irradiation means set portion that forms a position adjustment space for determining the position of the light irradiation means in the Z direction with respect to the Z reference portion, and the method comprises a holding step of holding the light irradiation means in a jig having a holding portion for holding the light irradiation means and a contact portion formed at a predetermined distance from the holding portion, a Z-direction positioning step of bringing the contact portion and the Z reference portion into contact with the housing and positioning the light irradiation means at a predetermined position within the light irradiation means set portion, and a first fixing step of fixing the light irradiation means at the predetermined position of the housing.

[0014] In this case, it is preferable that the light irradiation means set section has an XY reference section that serves as a reference for the position of the light irradiation means in the X and Y directions perpendicular to the Z direction, and that the XY direction arrangement step involves bringing the side surface of the light irradiation means into contact with the XY reference section and arranging the light irradiation means at a predetermined position within the light irradiation means set section.

[0015] Furthermore, the first fixing step may involve fixing the light irradiation means and the housing with an adhesive.

[0016] The device may also include a second fixing step in which an optical element having an uneven shape that exhibits optical functionality is fixed to the housing in a state in contact with a contact surface of the housing formed at a predetermined position in the Z direction from the Z reference portion.

[0017] Furthermore, the second fixing step may involve fixing the optical element to the housing with an adhesive outside the portion of the optical element that is in contact with the contact surface.

[0018] Furthermore, the optical element may be formed from an elastic resin member having the uneven shape on at least the surface on the light irradiation means side, and the second fixing step may involve sealing the space between the optical element and the contact surface of the housing with the elastic resin member and then fixing it with the adhesive.

[0019] Furthermore, the optical element may be formed from an elastic resin member having the uneven shape on at least the surface on the light irradiation means side, and the second fixing step may involve fixing it with the adhesive while applying pressure until the position of the recess of the uneven shape extends beyond the contact surface toward the light irradiation means side.

[0020] In this invention, the position of the light irradiation means in the Z-direction can be freely adjusted within the range of the Z-direction size of the position adjustment space of the light irradiation means set section. Therefore, even if there are some changes in the combination of the light irradiation means and the optical element, the distance between the light irradiation means and the optical element can be adjusted without changing the housing.

[0021] 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.

[0022] Examples of 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 examples only. In addition, in describing the examples described later, the same reference numerals are used for the same components as in the previously mentioned examples, and redundant explanations are omitted.

[0023] As shown in Figures 2 to 4, the optical system 100 of the present invention mainly consists of at least a light irradiation means 1 capable of irradiating light, and a housing 2 that holds the light irradiation means 1 so that its optical axis is oriented in the Z direction. The optical system 100 may also further have an optical element 3 having an uneven shape 31 that exhibits optical functions. In Figure 3, the optical system 100 is configured to include a housing 2, a light irradiation means 1 provided on the lower side of the housing 2, and an optical element 3 provided on the upper 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. The light irradiation means 1, housing 2, and optical element 3 will be described with reference to Figures 1 to 3.

[0024] [Housing 2] As shown in Figure 1, housing 2 has a Z reference section 22 that serves as a reference for the position of the light irradiation means 1 in the Z direction, and a light irradiation means set section 21 for arranging the light irradiation means 1. Housing 2 may also further have an optical element set section 26 for arranging the optical element 3. Housing 2 may be made of any conventionally known material, for example, a heat-resistant resin material or ceramics can be used.

[0025] 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 of 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.

[0026] 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. In addition, 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.

[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] The optical element set section 26 has a contact surface 27 formed at a predetermined position in the Z direction with respect to the Z reference section 22. 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. Furthermore, 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, so that the light irradiation means 1 and the optical element 3 can be positioned at a precise distance apart in the Z direction. 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 with respect to the Z reference section only needs to be 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.

[0029] 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.

[0030] 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.

[0031] [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.

[0032] 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.

[0033] 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 arranges the light source units 11 so that their arrangement direction faces a specific direction on the substrate 12. The substrate 12 also has an irradiation means side fixing location 13 on its side, which is fixed to the light irradiation means set section 21 of the housing 2 with adhesive 4 or the like. Furthermore, 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 material or ceramics can be used.

[0034] [Optical element 3] The optical element 3 has an uneven surface 31 that provides optical functionality. As shown in Figure 3, for example, the optical element 3 is composed of an optical element body 32 made of glass, resin, or the like, and a resin member 33 having an uneven surface 31 on the surface 321 of the optical element body 32. The optical element body 32 and the resin member 33 may be integrally formed from the same material.

[0035] The uneven surface shape 31 of the optical element 3 can be any shape that can perform optical functions 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 uneven surface 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 performs optical functions. For example, the uneven surface shape may be one that irradiates the entire irradiation area with a predetermined light distribution, one that irradiates in a dot pattern, one that irradiates in a line pattern, etc.

[0036] 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, in order to prevent adhesive 5 from being applied to the contact surface 27 that may come into contact with the uneven shape 31, 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). It is preferable to use an elastic resin (elastic resin member 34) as the resin member 33. Examples of elastic resins include silicone rubber such as polydimethylsiloxane (PDMS). This allows the elastic resin member 34 to be used as a seal to seal the space between the optical element 3 and the contact surface 27 of the housing 2, thereby reliably preventing the adhesive 5 from seeping into the recess 31b. In this case, it is preferable that the optical element 3 be fixed in a position where the recess 31b of the uneven shape 31 is on the light irradiation means side of the contact surface 27, as shown in Figure 3. 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.

[0037] Next, the manufacturing method of the optical system 100 of the present invention will be described. The manufacturing method of the optical system 100 of the present invention mainly consists of a holding step, a Z-direction arrangement step, and a first fixing step, and includes a light irradiation means mounting step (see Figure 5) in which the light irradiation means 1 is attached to the housing 2. The light irradiation means mounting step may further include an XY-direction arrangement step before the first fixing step. Furthermore, the manufacturing method of the optical system 100 may further include at least a second fixing step, and may include an optical element mounting step (see Figure 6) in which the optical element 3 is attached to the housing 2.

[0038] [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.

[0039] [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.

[0040] [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.

[0041] [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.

[0042] [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 to bring 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 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.

[0043] [First Fixing Step] The first fixing step 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.

[0044] In addition, as the adhesive 4, any adhesive can be used as long as it can securely bond the light irradiation means 1 and the housing 2. 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-curing type or a photo-thermal combined curing type adhesive because it has high productivity and can suppress the thermal influence on the optical element.

[0045] [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, the left-hand side figures are partial cross-sectional front views, and the right-hand side figures are plan views corresponding to the left-hand side figures excluding the jig. Note that a drive mechanism for driving the jig and a control mechanism for controlling it, etc. are not shown and the description is omitted.

[0046] [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 from the center of the jig body to the holding portion 91. Thereby, the optical element 3 can be reliably adsorbed and held by the holding portion 91 by the suction operation of the suction hole 95. In addition, the jig 9 is preferably movable at least in the Z direction, and more preferably formed to be movable also in the X direction and the Y direction. A known drive mechanism for driving the jig 9 and a control mechanism for controlling it, etc. may be used. Note that the jig 8 for holding the light irradiation means 1 can also be used as the jig 9.

[0047] [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 resin member 33 (or 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 by the holding portion 91 by suction using the suction hole 95.

[0048] [Z-direction Arrangement Process] The Z-direction arrangement process is a process of bringing the contact surface 27 of the housing 2 into contact with the resin member 33 (or the elastic resin member 34) of the optical element 3 and arranging the optical element 3 at a predetermined position in the optical element set portion 26. Since the contact surface 27 is formed at a predetermined position in the Z direction with reference to the Z reference portion 22, the optical element 3 held by the holding portion 91 and the light irradiation means 1 fixed to the housing 2 are arranged at positions separated by a predetermined distance. Therefore, the positioning of the light irradiation means 1 fixed to the housing 2 and the optical element 3 in the Z direction can be achieved.

[0049] [XY-direction Arrangement Process] The XY-direction arrangement process is to bring the side surface of the optical element 3 into contact with the XY reference portion 28 and arrange the optical element 3 at a predetermined position in the optical element set portion 26. Specifically, first, as shown in FIG. 6(a), the housing 2 to which the light irradiation means 1 is attached in the light irradiation means attachment process is placed with the optical element set portion 26 on the upper side. Next, as shown in FIG. 6(b), the housing 2 or the jig 9 is moved in the Z direction to bring the contact surface 27 of the housing 2 into light contact with the resin member 33 (or the elastic resin member 34) of the optical element 3. In this state, as shown in FIG. 6(c), the housing 2 or the jig 9 is moved in the X direction to bring the X-side side surface of the optical element 3 into contact with the X reference portion 28x of the XY reference portion 28. Also, the housing 2 or the jig 8 is moved in the Y direction to bring the side surface of the optical element 3 into contact with the Y reference portion 28y of the XY reference portion 28. Thereby, the positioning of the housing 2 and the optical element 3 in the X direction and the Y direction can be achieved. Note that the XY-direction arrangement process may be performed before the Z-direction arrangement process. In this case, with the side surface of the optical element 3 in contact with the XY reference portion 28, the contact surface 27 of the housing 2 may be brought into contact with the resin member 33 (or the elastic resin member 34) of the optical element 3.

[0050] [Second Fixing Step] The second fixing step 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 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 by capillary action, etc. Therefore, in order to prevent the adhesive 5 from being applied to the contact surface 27 that may come into contact with the uneven shape 31, 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). Here, if 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 may be used as a seal, and the optical element 3 and the contact surface 27 of the housing 2 may 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 and then fix 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 pressurizing until the position of the recess 31b exceeds the position of the contact surface 27 towards the light irradiation means 1. 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 predetermined distance in the Z direction relative to the housing 2 due to the pressurizing. Also, when releasing the pressurizing after bonding, the optical element 3 moves a predetermined distance in the Z direction relative to the housing 2 due to the repulsive force of the elastic resin member 34.Therefore, it should be noted that in the Z-direction positioning step of the light irradiation means mounting step, the final movement distance Kh resulting from the pressurization and release of the pressurization must also be taken into consideration when positioning the light irradiation means 1 in a predetermined position within the light irradiation means set section 21. Finally, once the adhesive 5 has hardened, the suction at the suction hole 95 of the jig 9 is stopped, and the optical element 3 is removed from the jig 9. This fixes the optical element 3 in a predetermined position at a predetermined distance Ph away from the irradiation means reference position 15 of the light irradiation means 1.

[0051] Any adhesive 5 can be used as the adhesive 5, as long as it can reliably bond the optical element 3 and the housing 2. For example, epoxy adhesives, acrylic adhesives, cyanoacrylate adhesives, silicone adhesives, or resin adhesives that are mixtures thereof can be used as the adhesive 5. In particular, using an ultraviolet-curing type or a photothermal-curing type adhesive is preferable because it offers high productivity and suppresses thermal effects on the optical element.

[0052] 1: Light irradiation means 2: Housing 21: Light irradiation means set section 22: Z reference section 23: Position adjustment space 24: XY reference section (for light irradiation means) 26: Optical element set section 27: Contact surface 3: Optical element 31: Concave and concave shape 31b: Recess 34: Elastic resin component 4: Adhesive 5: Adhesive 8: Jig (for light irradiation means) 81: Holding section 82: Contact section 100: Optical system

Claims

1. An optical system comprising a light irradiation means capable of irradiating light, and a housing that holds the light irradiation means such that its optical axis is oriented in the Z direction, wherein the housing has a Z reference portion that serves as a reference for the position of the light irradiation means in the Z direction, and a light irradiation means set portion that forms a position adjustment space for determining the position of the light irradiation means in the Z direction with respect to the Z reference portion, and the light irradiation means is fixed in the position adjustment space without contact with the housing in the Z direction.

2. The optical system according to claim 1, wherein the light irradiation means set portion has an XY reference portion that serves as a reference for the position of the light irradiation means in the X and Y directions perpendicular to the Z direction, and the side surface of the light irradiation means and the XY reference portion are in contact.

3. The optical system according to claim 1, characterized in that the light irradiation means is fixed to the light irradiation means set portion of the housing with an adhesive.

4. The optical system according to claim 1, comprising an optical element having an uneven shape that exhibits optical functions, wherein the housing has an optical element set portion having a contact surface formed at a predetermined position in the Z direction with reference to the Z reference portion, and the optical element is fixed in contact with the contact surface.

5. The optical system according to claim 4, 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.

6. The optical system according to claim 5, characterized in that the optical element is formed of an elastic resin member having the uneven shape on at least the surface on the light irradiation means side, and the space between the optical element and the contact surface of the housing is sealed with the elastic resin member.

7. The optical system according to claim 6, characterized in that the optical element has a recess in the uneven shape located on the side of the light irradiation means that is closer to the contact surface.

8. A method for manufacturing an optical system comprising a light irradiation means capable of irradiating light and a housing that holds the light irradiation means such that its optical axis is oriented in the Z direction, wherein the housing has a Z reference portion that serves as a reference for the position of the light irradiation means in the Z direction and a light irradiation means set portion that forms a position adjustment space for determining the position of the light irradiation means in the Z direction with respect to the Z reference portion, and the method for manufacturing an optical system comprising: a holding step of holding the light irradiation means in a jig having a holding portion for holding the light irradiation means and a contact portion formed at a predetermined distance from the holding portion; a Z-direction positioning step of bringing the contact portion and the Z reference portion into contact with the housing and positioning the light irradiation means at a predetermined position within the light irradiation means set portion; and a first fixing step of fixing the light irradiation means at the predetermined position of the housing.

9. The method for manufacturing an optical system according to claim 8, characterized in that the light irradiation means set section has an XY reference section that serves as a reference for the position of the light irradiation means in the X and Y directions perpendicular to the Z direction, and the method for manufacturing an optical system according to claim 8 is characterized in that the side surface of the light irradiation means comes into contact with the XY reference section and the light irradiation means is positioned at a predetermined position within the light irradiation means set section.

10. The method for manufacturing an optical system according to claim 8, characterized in that the first fixing step is to fix the light irradiation means and the housing with an adhesive.

11. The method for manufacturing an optical system according to claim 8, characterized by having a second fixing step of fixing an optical element having an uneven shape that exhibits optical function to the housing in a state in contact with a contact surface of the housing formed at a predetermined position in the Z direction from the Z reference portion.

12. The method for manufacturing an optical system according to claim 11, characterized in that the second fixing step involves fixing the optical element to the housing with an adhesive outside the portion in contact with the contact surface.

13. The method for manufacturing an optical system according to claim 12, characterized in that the optical element is formed of an elastic resin member having the uneven shape on at least the surface on the light irradiation means side, and the second fixing step is to fix the optical element and the contact surface of the housing with the adhesive while the space between the optical element and the contact surface of the housing is sealed with the elastic resin member.

14. The method for manufacturing an optical system according to claim 12, characterized in that the optical element is formed of an elastic resin member having the uneven shape on at least the surface on the light irradiation means side, and the second fixing step involves fixing it with the adhesive while applying pressure until the position of the recess of the uneven shape extends beyond the contact surface toward the light irradiation means side.

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