Optical components

Abstract

This invention provides a configuration that miniaturizes optical components used in optical communications while ensuring stability during implementation. [Solution] The optical component comprises a rectangular transparent body having a height-to-width ratio greater than 1 in a plane perpendicular to the optical axis, and a lens provided on at least one of the light-emitting side and light-incident side of the transparent body. The lens body formed by the transparent body and the lens comprises a first surface including a flat contact surface, a second surface including a flat surface on the opposite side of the first surface, a first extension portion that extends from the first surface and protrudes only to one of the light-emitting side and light-incident side in the optical axis direction, and a second extension portion that extends from the second surface and protrudes only to one of the light-emitting side and light-incident side in the optical axis direction. The perpendicular line drawn from the center of gravity of the lens body to the contact surface and the line segment connecting the center of gravity and the center of the contact surface coincide within a predetermined range.

Description

Technical Field

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[0001] The present invention relates to optical components.

Background Art

[0002] Due to the spread of IoT (Internet of Things) and cloud services, the communication volume of optical networks has been continuously increasing rapidly, and further improvement in communication speed and quality is required. On the other hand, due to the demand for miniaturization of optical communication devices, miniaturization and high density are also required for individual optical components and optoelectronic components incorporated in communication modules.

[0003] A configuration is known in which protrusions are formed at the four corners of a rectangular lens used in optical communication or the like to increase the area of the lens mounting surface and firmly bond and fix the lens during installation (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004] <​​​​​​​​​​​​​​​​​​​​​The present invention aims to provide a configuration that miniaturizes optical components used in optical communications while also ensuring stability during implementation. [Means for solving the problem]

[0008] In one aspect of this disclosure, the optical component is A transparent rectangular prism whose height-to-width ratio is greater than 1 in a plane perpendicular to the optical axis, A lens provided on at least one of the light-emitting side and the light-incoming side of the transparent body, It has, The lens body formed by the transparent body and the lens has a first surface including a flat contact surface, The perpendicular line drawn from the center of gravity of the lens body to the contact surface and the line segment connecting the center of the contact surface and the center of gravity coincide within a predetermined range. [Effects of the Invention]

[0009] The above configuration allows for miniaturization of optical components used in optical communications and improves the stability of their mounting. This also reduces the size of optical modules using these components and improves operational reliability. [Brief explanation of the drawing]

[0010] [Figure 1] This diagram illustrates the problems with vertical lenses. [Figure 2] This is a schematic diagram of a transmitter / receiver including an optical module using the optical components of the embodiment. [Figure 3] This figure shows the optical components of the first embodiment. [Figure 4] This figure illustrates the parameters of the optical component in the first embodiment. [Figure 5] This figure shows an example of the configuration of the extension portion of the lens body. [Figure 6] This diagram illustrates a comparison between an optical component of the first embodiment and a general optical component. [Figure 7] This is a schematic diagram of the optical component of the second embodiment. [Figure 8]It is a schematic diagram of an optical component according to the third embodiment. [Figure 9] It is a schematic diagram of an optical component according to the fourth embodiment. [Figure 10] It is a schematic diagram of an optical component according to the fifth embodiment.

Embodiments for Carrying Out the Invention

[0011] Before explaining the configuration of the embodiment in detail, referring to FIG. 1, the technical problems in the vertical lens with reduced thickness will be explained in more detail.

[0012] FIG. 1 is a side view of a general lens used as an optical component. (A) in FIG. 1 is a schematic diagram seen in a longitudinal section, and (B) is an optical path diagram including the optical axis OA and the lens center of gravity. The lens center of gravity is indicated by a cross mark. The direction of light propagation is the X direction, the height direction of the lens is the Z direction, and the direction orthogonal to the X direction and the Z direction is the Y direction.

[0013] The lens has a bottom A, an upper part B, and a lens part LN. When mounting the lens on a substrate or the like, the lens is picked up at the upper part B and carried to the mounting position, and fixed at the mounting position at the bottom A. The lens part LN is a convex lens in this example, and collimates the incident laser light at the mounting position.

[0014] When the overall thickness of the lens is reduced for miniaturization, the lens center of gravity shifts forward along the optical axis OA, that is, toward the light emission side. In (B) of FIG. 1, the lens center of gravity indicated by the cross mark is shifted in the +X direction from the perpendicular line Lper directed from the center C1 of the bottom A toward the optical axis OA.

[0015] In other words, the line segment connecting the center C1 of the bottom A and the lens center of gravity is inclined by an angle θoff in front of (the +X direction) the perpendicular line Lper. As a result, as shown by the white arrow in the figure, the lens is likely to fall forward (in the +X direction) in the thickness direction. When the lens has a lens part on the back surface of the lens, that is, the incident side of the laser light, depending on the position of the center of gravity of the lens, the lens is likely to fall backward (in the -X direction).

[0016] In addition to reducing the thickness of the lens for miniaturization, if the width of the lens (size in the Y direction) is narrowed, the fixed area of the bottom A becomes smaller, and it becomes difficult for the lens to stand on its own during lens mounting. If the center of gravity of the lens is displaced, the lens may be fixed while tilted diagonally.

[0017] When the area of the upper surface of the upper part B becomes smaller, it becomes difficult to stably pick up or hold the lens. When using vacuum suction, the suction force acting on the upper surface of the lens becomes smaller, and there is a risk that the lens may fall during movement.

[0018] In the embodiment, at least a part of the above-described problems is solved, and a configuration is provided that can stably mount a rectangular parallelepiped lens with reduced thickness and width.

[0019] FIG. 2 is a schematic diagram of an optical transmitter 1 to which the optical component 10 of the embodiment is applied. The optical transmitter 1 includes a digital signal processor (DSP) 2, an optical module 5, and a multiplexer 6. The optical module 5 is a front-end module for optical transmission, and in this example, it is formed as a 4-channel optical transmission module. Solid arrows represent electrical signals, and dashed arrows represent optical signals.

[0020] The optical module 5 includes a driver circuit DRV provided for each channel, a laser diode (LD) as a light source, and an optical component 10. The driver circuit DRV generates a drive signal for driving the LD based on the modulation data signal generated by the DSP 2. In each channel, the LD is designed for different wavelengths λ0 to λ3 and outputs a modulated optical signal corresponding to the input drive signal.

[0021] Corresponding to each of the plurality of LDs, optical components 10-1 to 10-4 are arranged. When the demand for miniaturization of the optical module 5 is strict, it is desirable that the optical components 10-1 to 10-4 be arranged individually rather than integrated into an array. This is because the optical loss can be minimized in a narrow space by individually adjusting the positions, orientations, etc. of the optical components 10-1 to 10-4 according to the arrangement accuracy of the LDs.

[0022] Light of each wavelength, collimated or focused by optical components 10-1 to 10-4, is combined in a multiplexer 6. The light combined in the multiplexer 6 is then input into, for example, an optical fiber and transmitted to a server in a data center.

[0023] In Figure 2, optical components 10-1 to 10-4 are schematically depicted as square boxes, but in reality, they have an elongated shape with reduced width in the channel arrangement direction and thickness in the optical axis direction. When the position and orientation of optical components 10-1 to 10-4 of this shape are individually adjusted inside the optical module 5, the optical components 10 need to be stable on their own. The following embodiment describes the configuration of a small and stable optical component.

[0024] <First Embodiment> Figure 3 shows the optical component 10 of the first embodiment. In Figure 3, (A) is an optical path diagram, (B) is a front view seen from the direction of light propagation (X direction), and (C) is a perspective view. Similar to Figure 1, the direction of light propagation is the X direction, the height direction of the optical component 10 is the Z direction, and the direction perpendicular to the X and Z directions is the Y direction. The Y direction is the direction along the width of the optical component 10.

[0025] The optical component 10 includes a vertically elongated transparent body 110 and a lens 15 provided on at least one of the light-emitting and light-incoming sides of the transparent body 110. The transparent body 110 and the lens 15 form the lens body 100. The transparent body 110 has a rectangular parallelepiped shape in a plane perpendicular to the optical axis OA, where the ratio of height to width is greater than 1. For example, if the width of the transparent body 110 is set to 0.6 mm or less, the height of the lens body 100 is 1.0 mm.

[0026] The lens body 100 has a bottom portion 11 and an upper portion 12. The bottom portion 11 has a first surface 115 which serves as the mounting surface for the optical component 10. The upper portion 12 has a second surface 125 located on the opposite side of the first surface 115. When mounting the optical component 10, the upper portion 12 is held by vacuum suction, mechanical chucking, etc., and transported to a predetermined mounting position. At the mounting position, the position, angle, etc. of the optical component 10 relative to the LD are finely adjusted. Once the arrangement and orientation of the optical component 10 are determined, the optical component 10 is fixed to the substrate, etc., by the first surface 115. More specifically, the optical component 10 is fixed to the substrate, etc., by the flat contact surface 115a included in the first surface 115.

[0027] Lens 15 is provided between the bottom 11 and the top 12 and collimates the incident light from the LD into parallel light. Alternatively, the shape of lens 15 may be adjusted to focus the incident light to a predetermined position. When the width and height of the lens body 100 are set to 0.6 mm × 1.0 mm, the radius of lens 15 is, for example, 0.27 mm to 0.28 mm. When viewed in a vertical cross-section along the optical axis OA, the shape of lens body 100 is asymmetrical in the direction of the optical axis, that is, it has different cross-sectional shapes on the light emission side and the light incidence side.

[0028] Optical components with reduced thickness in the optical axis direction and asymmetrical along the optical axis are prone to tipping over due to a shift in the optical axis direction of their center of gravity, as explained with reference to Figure 1. To solve this problem, the optical component 10 of the first embodiment is designed so that the center of gravity of the lens body 100 (indicated by the cross mark) and the center of the contact surface 115a of the optical component 10 lie on the same perpendicular line.

[0029] In a more preferred example, the center of gravity of the lens body 100, the center C1 of the contact surface 115a, and the center C2 of the upper part 12 are located on the same perpendicular line. The second surface 125 of the upper part 12 has a flat surface 125a used for vacuum adsorption, etc. The center of gravity of the lens body 100 is located on the perpendicular line connecting the center C1 of the contact surface 115a of the bottom part 11 and the center C2 of the flat surface 125a of the upper part 12.

[0030] To ensure the stability of the optical component 10, the lens body 100 may have a first extension 111 protruding in the optical axis direction from its bottom 11. The first extension 111 may be formed over the entire width of the bottom 11. The amount of protrusion of the first extension 111 in the optical axis direction may be uniform across the width. This increases the bottom area and stabilizes the optical component 10.

[0031] A second extension 121 protruding in the optical axis direction may be provided on the upper part 12 of the lens body 100. The second extension 121 may be formed with a constant protrusion amount over the entire width of the upper part 12. This increases the pickup area when transporting the optical component 10 to the mounting position and stabilizes the posture of the optical component 10 during movement.

[0032] Figure 4 is a diagram illustrating the parameters of the optical component 10. This figure is a vertical cross-sectional view of the optical component 10 along the optical axis OA. The lens body 100 has a center of gravity COM on the optical axis OA. The size of the first surface 115 of the bottom portion 11 in the optical axis direction is d12, and the size of the contact surface 115a in the optical axis direction is d11. Preferably, d11 is greater than half of d12. Making d11 greater than half of d12 improves the mounting stability of the optical component 10. As an example, if d12 is 0.48 mm to 0.50 mm, then d11 is 0.33 mm to 0.35 mm.

[0033] Figure 4 shows the ideal form of the optical component 10, where the perpendicular L1 drawn from the centroid COM to the contact surface 115a coincides with the line segment L2 connecting the centroid COM and the center C1 of the contact surface 115a. In other words, in a vertical cross-section along the optical axis OA, the intersection point of the perpendicular Lper (see Figure 1) from the center C1 of the contact surface 115a toward the optical axis OA coincides with the centroid COM.

[0034] The angle between the line connecting the center of gravity COM and the rear end 116 of the contact surface 115a and the perpendicular L1 is defined as the tilt angle θa. The tilt angle θa correlates with the force acting from the surface on which the optical component 10 is mounted toward the front (+X side) of the lens body 100.

[0035] The angle between the line connecting the center of gravity COM and the front end 117 of the contact surface 115a and the perpendicular L1 is defined as the tilt angle θb. The tilt angle θb correlates with the force acting from the surface on which the optical component 10 is mounted toward the rear (-X side) of the lens body 100.

[0036] In Figure 4, the optical component 10 is balanced at θa=θb and is stable on its own. More preferably, the extensions of L1 and L2 pass through the center C2 of the flat surface 125a of the upper part 12. The optical component 10 is not necessarily limited to this ideal form. The perpendicular line L1 and the line segment L2 may be offset to a certain extent within an acceptable range. This will be discussed later with reference to Figure 6.

[0037] Figure 5 shows an example of the parameters for the extension portion of the lens body 100. In Figure 5, the second extension portion 121 of the upper part 12 is shown as an example, but if the upper part 12 and the bottom part 11 are formed symmetrically with respect to the optical axis OA, the parameters in Figure 5 will directly apply to the first extension portion 111 of the bottom part 11.

[0038] The second extension 121 is continuous with the flat surface 125a of the upper part 12 and protrudes in the optical axis direction (in this example, the +X direction). Similarly, the first extension 111 of the bottom part 11 is continuous with the contact surface 115a and protrudes in the optical axis direction (see Figure 4).

[0039] The height h of the second extension 121 is set to a height that is less likely to chip, taking into account the overall dimensions of the lens body 100. For example, when the width and height of the lens body 100 are set to 0.6 mm x 1.0 mm, it is preferable that the height h of the second extension 121 be 0.2 mm or more. The same applies to the height of the first extension 111 of the bottom 11.

[0040] The second extension 121 may have a curved surface 123 continuous with the flat surface 125a, a flat vertical surface 124 continuous with the curved surface 123, and an inclined surface 122 continuous with the vertical surface 124. The flat surface 125a and the curved surface 123 form the second surface 125. The amount of projection d13 of the second extension 121 in the X direction may be set to about half of the difference between d12 and d11 in Figure 4. For example, d13 is 0.07 mm to 0.08 mm.

[0041] The inclination angle θ of the inclined surface 122 from the Z direction is, for example, 40° to 50°, and in the example of Figure 5, it is set to 45°. A flat portion 126 may be provided between the second extension 121 and the lens 15. The height d15 of the flat portion 126 is about 0.03 mm. By providing the flat portion 126, the lens 15 and the inclined surface 122 are connected at an obtuse angle, preventing a sharp cut. By forming the second extension 121 with a curved surface 123, a vertical surface 124, and an inclined surface 122, and providing a flat portion 126 between the lenses 15, a shape that is less prone to chipping can be obtained. The same configuration applies to the first extension 111.

[0042] Figure 6 shows an example of the configuration of the optical component 10 within the tolerance range. The perpendicular L1 drawn from the center of gravity COM to the contact surface 115a and the line segment L2 connecting the center of gravity COM and the center C1 may be offset within a predetermined range. In Figure 6(A), the perpendicular L1 and line segment L2 of the optical component 10 are offset by an angle of 1°.

[0043] The angle of misalignment between perpendicular line L1 and line segment L2 is within an acceptable range as long as it is 10% or less of the larger of the tilt angles θa and θb, and the stability of the vertically elongated lens body 100 is maintained. Note that the angle of misalignment between perpendicular line L1 and line segment L2 is approximately half the difference between the tilt angles θa and θb.

[0044] Figure 6(B) shows, for comparison, the displacement angle in the typical lens configuration of Figure 1. The displacement angle between the perpendicular L1 and the line segment L2 is 2.3°, and the center of gravity COM is tilted forward (in the X direction). This displacement angle exceeds 10% of the tilt angle θa, and stability cannot be ensured.

[0045] In the optical component 10 of the first embodiment, the perpendicular L1 drawn from the center of gravity COM of the lens body 100 to the contact surface 115a of the bottom 11 and the line segment L2 connecting the center of gravity COM and the center C1 of the contact surface 115a substantially coincide within the range of the allowable misalignment angle. This allows the optical component 10 to stand on its own at the mounting position, enabling stable position adjustment or angle adjustment.

[0046] When the angle of deviation between the perpendicular L1 and the line segment L2 is within the tolerance range, the extension of the perpendicular L1 passes near the center of the flat surface 125a of the upper part 12. The orientation of the optical component 10 is stable when transporting it to the mounting position, and the optical component 10 can be reliably transported to the mounting position.

[0047] <Second Embodiment> Figure 7 is a schematic diagram of the optical component 10A of the second embodiment. The optical component 10A is shown in a vertical cross-section along the optical axis OA.

[0048] The optical component 10A has a first extension portion 111A and a second extension portion 121A on the back surface of the lens body 100A, i.e., the light incident side. The first extension portion 111A is formed continuously in the -X direction from the contact surface 115a of the bottom portion 11. The second extension portion 121A is formed continuously in the -X direction from the flat surface 125a of the upper portion 12.

[0049] By providing the first extension portion 111A and the second extension portion 121A on the side opposite to the lens 15, it becomes easier to balance the lens body 100A in the optical axis direction, resulting in greater stability. Since the first extension portion 111A and the second extension portion 121A are provided on the flat back surface opposite to the lens 15, the shapes of the first extension portion 111A and the second extension portion 121A are simplified, making them less prone to chipping.

[0050] As in the first embodiment, the perpendicular L1 drawn from the centroid COM of the lens body 100A to the contact surface 115a and the line segment L2 connecting the center C1 of the contact surface 115a and the centroid COM coincide approximately within a predetermined range. Furthermore, the length d11 of the contact surface 115a in the optical axis direction is set to be greater than half the length d12 of the first surface 115 in the optical axis direction.

[0051] By providing the first extension portion 111A and the second extension portion 121A on the back side of the lens body 100A, the center of gravity COM is shifted towards the back side of the lens body 100A compared to the first embodiment. The contact surface 115a is positioned slightly forward of the lens body 100A such that the perpendicular L1 drawn from the center of gravity COM to the contact surface 115a coincides within a predetermined range with the line segment L2 connecting the center C1 of the contact surface 115a and the center of gravity COM.

[0052] In a more preferred configuration, the flat surface 125a of the second surface 125 of the upper part 12A is positioned slightly forward of the lens body 100A, and the extension of the perpendicular line L1 passes near the center of the flat surface 125a of the second surface 125. This configuration makes it easier for the optical component 10A to stand upright at the mounting position, and stabilizes the posture of the optical component 10A during transport to the mounting position, ensuring reliable transport.

[0053] <Third Embodiment> Figure 8 is a schematic diagram of the optical component 10B of the third embodiment. The optical component 10B is shown in a vertical cross-section along the optical axis OA.

[0054] In the optical component 10B, extensions are provided on both the light-emitting side (+X direction) and the light-incident side (-X direction) of the lens body 100B. At the bottom portion 11B, the first extension is formed by the light-emitting side extension 111Ba and the light-incident side extension 111Bb. At the upper portion 12B, the second extension is formed by the light-emitting side extension 121Ba and the light-incident side extension 121Bb.

[0055] The light-emitting extensions 111Ba and 121Ba are formed in a shape that does not come into contact with the lens 15 and does not contain sharp angles, making them less prone to chipping. The light-incoming extensions 111Bb and 121Bb have a shape with few irregularities. This configuration is suitable when there is no space between the LD and the optical component 10B.

[0056] The amount of protrusion of the extended portion is distributed between the light emission side and the light incidence side, and on the first surface 115, the contact surface 115a occupies a large proportion, resulting in a large fixing area during mounting. On the second surface 125, the flat surface 125a occupies a large proportion, allowing the optical component 10B to be held with strong suction force during transport.

[0057] The perpendicular line L1 drawn from the center of gravity COM of the lens body 100B to the contact surface 115a and the line segment L2 connecting the center of gravity COM and the center C1 of the contact surface 115a substantially coincide within a predetermined range, as in the first and second embodiments. The optical component 10B can stand stably on its own even in a narrow space in the direction of the optical axis.

[0058] <Fourth Embodiment> Figure 9 is a schematic diagram of the optical component 10C of the fourth embodiment. The optical component 10C is shown in a vertical cross-section along the optical axis OA. In the optical component 10C, the bottom portion 11C of the lens body 100C has extensions that protrude on both sides along the optical axis, and the upper portion 12C has an extension that protrudes on only one side.

[0059] At the bottom portion 11C, the first extension is formed by the extension portion 111Ca on the light emission side and the extension portion 111Cb on the light incidence side. At the upper portion 12B, the extension portion 121C on the light incidence side becomes the second extension.

[0060] The light-emitting extension portion 111Ca of the bottom portion 11C is formed in a shape that does not come into contact with the lens 15 and does not contain any sharp angles, making it less prone to chipping. The light-incoming extension portions 111Cb and 121C have a shape with few irregularities. This configuration is suitable when there is no space between the LD and the optical component 10B.

[0061] At the bottom portion 11C, the protrusion of the extended portion is distributed between the light emission side and the light incidence side, ensuring a wide contact surface 115a. At the upper portion 12C, irregularities in the optical axis direction are minimized. The optical component 10C can stand stably even in a narrow space in the optical axis direction.

[0062] The fact that the perpendicular L1 drawn from the center of gravity COM of the lens body 100C to the contact surface 115a and the line segment L2 connecting the center C1 of the contact surface 115a and the center of gravity COM substantially coincide within a predetermined range is the same as in the first to third embodiments. By designing the extension of the perpendicular L1 to pass through the center or near the center of the flat surface 125a of the upper part 12C, the optical component 10C can be transported in a stable position even if the lens body 100C is not vertically symmetrical with respect to the optical axis OA.

[0063] <Fifth Embodiment> Figure 10 is a schematic diagram of the optical component 10D of the fifth embodiment. The optical component 10D is shown in a vertical cross-section along the optical axis OA. The optical component 10D has a first extension portion 111D only at its bottom portion 11D. The upper portion 12D has no irregularities in the direction of the optical axis. This configuration is suitable for gripping by mechanical chucking 20. The optical component 10D can be securely gripped by the flat surface on the back (light incident side) of the lens body 100D and the flat surface on the front (lens side) of the upper portion 12D.

[0064] The fact that the perpendicular L1 drawn from the center of gravity COM of the lens body 100D to the contact surface 115a and the line segment L2 connecting the center C1 of the contact surface 115a and the center of gravity COM substantially coincide within a predetermined range is the same as in the first to fourth embodiments. The optical component 10D has self-supporting stability and is easy to process because of its simple shape.

[0065] Although the above has been described based on a specific configuration example, the present invention is not limited to the above-described configuration example. The lens 15 does not need to be placed only on the light emission side; it may be provided on the incident surface, or on both the incident and emission surfaces. In either case, the perpendicular L1 drawn from the center of gravity of the lens body to the contact surface at the bottom and the line segment L2 connecting the center of the contact surface and the center of gravity coincide within a predetermined range.

[0066] The first to fifth embodiments described above are interchangeable. For example, in the configuration of Figure 7 (second embodiment), an extension protruding toward the light emission side (+X direction) may be provided on one or both of the bottom 11A and the top 12A of the lens body 100A. In the bottom 11D of Figure 10 (fifth embodiment), in addition to the first extension 111D, an extension protruding toward the light incidence side (-X direction) may be provided to distribute the amount of protrusion in the optical axis direction.

[0067] These configurations ensure that the center of gravity COM of the lens body and the center C1 of the contact surface lie on the same perpendicular line L1, stabilizing the orientation of the optical component during mounting and preventing tilting or tipping. Furthermore, by positioning the center C2 of the upper flat surface on the extension of the perpendicular line L1, the orientation of the optical component 10 is stabilized when transporting it to the mounting position. Even when the optical component is moved quickly to the mounting position, gripping by vacuum suction or mechanical chucking remains stable. Since the positioning adjustment of the optical component is stable at the mounting position, the overall assembly time of the optical component 10 can be reduced.

[0068] This international application claims priority based on Japanese Patent Application No. 2020-101765, filed on 11 June 2020, and includes the entire contents of that Japanese Patent Application. [Explanation of Symbols]

[0069] 1. Optical Transmitter 5 Optical Modules 10, 10-1 to 10-4, 10A to 10D optical components 11, 11A~11D bottom 12, 12A~12D upper part 15 lenses 100, 100A~100D Lens Body 110 Transparent body 111, 111A, 111D 1st extension part 115 Page 1 115a Contact surface 121, 121A, 121C 2nd extension 125 2nd page 125a flat surface COM center of gravity OA optical axis L1 Perpendicular line from the center of gravity to the contact surface L2 is the line segment connecting the center of gravity and the center of the contact surface. Perpendicular line from the center of the Lper contact surface to the optical axis. C1 Center of the contact surface Center of the flat surface C2

Claims

1. A transparent rectangular prism whose height-to-width ratio is greater than 1 in a plane perpendicular to the optical axis, A lens provided on at least one of the light-emitting side and light-incoming side of the transparent body, It has, The lens body formed by the transparent body and the lens is A first surface including a flat contact surface, A second surface, which includes a flat surface, is located opposite to the first surface. A first extension portion that extends continuously from the first surface and protrudes only from either the light emission side or the light incidence side in the optical axis direction, A second extension portion extends continuously from the second surface and protrudes only from one of the light emission side and light incidence side in the optical axis direction, It has, An optical component in which the perpendicular line drawn from the center of gravity of the lens body to the contact surface and the line segment connecting the center of gravity and the center of the contact surface coincide within a predetermined range.

2. The optical component according to claim 1, wherein the predetermined range is such that the angle of deviation between the perpendicular and the line segment is within 10% of the angle of inclination between the line connecting the center of gravity and the rear or front end of the contact surface and the perpendicular.

3. The optical component according to claim 1 or 2, wherein the length of the contact surface in the optical axis direction is greater than half the length of the first surface in the optical axis direction.

4. The optical component according to claim 1, wherein the first extension is formed over the entire width of the transparent body.

5. The optical component according to claim 4, wherein the amount of the first extension portion protruding in the optical axis direction is constant in the width direction of the lens body.

6. The optical component according to claim 1, wherein the center of the flat surface is located on the extension of the perpendicular line.

7. The optical component according to claim 1, wherein the lens is located between the first extension and the second extension.

8. The optical component according to claim 7, wherein a flat portion is provided between the lens and at least one of the first extension and the second extension.

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