JP2014048493A - Optical member and optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the light transmission performance from a light emission member to a light incident member, by improving the condensation property of light beams and reducing light loss in an optical member.SOLUTION: The optical member of the present invention includes a tapered optical path whose cross section increases from one end to the other end, and a lens member disposed on the optical axis extended from the other end side of the tapered optical path.

Description

  The present invention relates to an optical member and an optical device, and more particularly to an optical member suitable for an optical connector for propagating light from a light emitting member to a light incident member and an optical device including the optical member.

  In general, since optical transmission enables high-speed communication of a large amount of information, optical fibers are widely used in communication fields such as trunk lines and access systems. Further, for example, automobiles are equipped with various electrical components (for example, a car navigation system), and optical fibers are also employed for optical communication of these electrical components. The optical fiber is provided with a light emitting member that emits an optical signal on one end side and a light receiving member on the other end side, and the optical signal is propagated through the optical fiber as an optical path. Conventionally, various optical fiber connectors have been used to optically connect these light receiving / emitting members and optical fibers (see, for example, Patent Document 1).

  On the other hand, development of an optical interconnection technology that uses optical signals not only for communication fields such as trunk lines and access systems, but also for information processing in routers and servers is underway. Conventionally, since light is used for short-distance signal transmission between boards in a router or a server device or in a board, the optical path has a higher degree of freedom of wiring and higher density than an optical fiber. Various optical connectors using optical waveguides are also known (see, for example, Patent Document 2).

  Incidentally, a light beam emitted from a light emitting element such as a laser diode or a light beam emitted from the element via an optical fiber or an optical waveguide has a large divergence angle. Therefore, in the connector using the optical fiber or the optical waveguide, it is necessary to accurately align the optical fiber or the optical waveguide with another optical member such as a light emitting element, and there is a problem that the alignment tolerance is low. .

  Conventionally, for the purpose of improving the alignment tolerance, the cross-sectional area on one end side is reduced corresponding to the light receiving area of the light receiving element, and the cross-sectional area on the other end side is increased corresponding to the beam diameter of the light emitting element. A tapered optical waveguide is known (see Patent Document 3).

JP 2003-167175 A JP 2000-340905 A WO2012 / 070585 pamphlet

As shown in FIG. 11, in the tapered optical waveguide 100 of Patent Document 3, for example, an optical signal from the light emitting element 101 is incident on the end portion on the large diameter side and is emitted from the end portion on the small diameter side to receive light. Light is received by the element 102 and an optical signal is transmitted.
However, the spread angle of the optical signal emitted from the emission end of the optical waveguide 100 is larger than that of a normal optical waveguide, and there is a possibility that the optical signal component not received by the light receiving element 102 increases and the light transmission performance deteriorates. is there. If the diameter on the incident end side of the optical waveguide 100 is increased or the diameter on the exit end side is decreased, the incident angle of the light beam to the core-cladding interface increases as shown in FIG. There is also a problem that light leaks from the core during propagation of the waveguide 100, leading to light propagation loss.

  The present invention has been made in view of the above problems, and an object of the present invention is to improve the light condensing property of light when propagating light from a light emitting member to a light incident member, An object of the present invention is to provide an optical member capable of improving light transmission performance by reducing loss.

That is, the present invention provides the following [1] to [18].
[1] An optical member having a tapered optical path in which a cross-sectional area of the optical path increases from one end to the other end, and a lens member disposed on an optical axis extending from the other end side of the tapered optical path.
[2] The optical member according to [1], wherein the tapered optical path is a core, and the core is surrounded by a clad having a lower refractive index than the core.
[3] The optical member according to [1] or [2], wherein an optical path conversion mirror is disposed between the tapered optical path and the lens member on the optical axis.
[4] The optical member according to [3], wherein a substrate is disposed between the lens member and the optical path conversion mirror.
[5] The optical member according to [2], wherein the tapered optical path is formed by an optical waveguide having a core pattern including the plurality of cores.
[6] The optical member according to any one of [1] to [5], wherein the optical path is tapered so that at least one of a width and a height increases toward the other end.
[7] The optical member according to any one of [1] to [6], wherein the lens member is a semi-convex lens having one convex surface.
[8] The optical member according to [7], wherein a convex surface side of the semi-convex lens is disposed on the opposite side of the tapered optical path along the optical axis.
[9] The optical member according to any one of [1] to [8], wherein the lens member is a condenser lens system.
[10] The optical member according to any one of [1] to [9], a light emitting member that emits a light beam toward the one end side of the tapered optical path, and the other end side of the tapered optical path. An optical device comprising: a light incident member on which a light beam emitted from the light enters through the lens member.
[11] The optical device according to [10], wherein the light emitting member is configured by a second optical path.
[12] A light beam is incident on the one end of the tapered optical path from an end of the second optical path, and a sectional area of one end of the tapered optical path is equal to or larger than a sectional area of the end of the second optical path. The optical device according to [11], wherein
[13] The optical device according to any one of [10] to [12], wherein a cross-sectional area of the other end of the tapered optical path is smaller than a projected area of the lens member.
[14] The optical member according to any one of [1] to [9], a light emitting member that emits a light beam toward the other end side of the tapered optical path via the lens member, An optical device comprising: a light incident member into which a light beam emitted from one end side of the tapered optical path is incident.
[15] The optical device according to [14], wherein the light incident member is configured by a second optical path.
[16] A light beam is incident on an end portion of the second optical path from the one end of the tapered optical path, and a cross-sectional area on one end side of the tapered optical path is a cross-sectional area of the end portion of the second optical path. The optical device according to [15], wherein:
[17] The light according to [11] or [15], wherein the second optical path is formed of an optical fiber or an optical waveguide including a core and a clad having a refractive index lower than that of the core and surrounding the core. device.
[18] The optical device according to [11] or [15], wherein a cross-sectional area of the second optical path is constant from one end to the other end.

  The optical member with a lens in the present invention can improve the light beam condensing property, and can improve the light transmission performance from the light emitting member to the light incident member by reducing the light loss in the optical member. .

It is sectional drawing which shows the optical device which concerns on the 1st Embodiment of this invention. It is a perspective view which shows the optical member which concerns on the 1st Embodiment of this invention. 1 is a plan view showing an optical device according to a first embodiment of the present invention. It is a schematic diagram for demonstrating operation | movement of the optical device which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the optical device which concerns on the 2nd Embodiment of this invention. It is a schematic diagram for demonstrating operation | movement of the optical device which concerns on the 2nd Embodiment of this invention. It is a schematic diagram for demonstrating operation | movement of the optical device which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the optical device which concerns on the 3rd Embodiment of this invention. It is a schematic diagram which shows the comparison with the propagation of the light of this invention. It is a conceptual diagram which shows the comparison with the propagation of the light of this invention. It is a conceptual diagram which shows the comparison with the propagation of the light of this invention. It is a conceptual diagram which shows the comparison with the propagation of the light of this invention.

Hereinafter, the present invention will be described in more detail with reference to embodiments.
1 and 3 show an optical device according to a first embodiment of the present invention. FIG. 2 shows the optical member in the first embodiment.
The optical device includes an optical member 20, a light emitting member 30 that emits a light beam to the optical member 20, and a light incident member 40 on which the light beam emitted from the optical member 20 is incident. The optical member 20 includes a tapered optical waveguide 21 having a tapered optical path 19 and a lens member 27. For example, the optical member 20 functions as an optical connector that causes a light beam emitted from the light emitting member 30 to enter the light incident member 40. Have.

(Tapered optical waveguide)
The tapered optical waveguide 21 includes a core pattern 22 and a clad 23 having a refractive index lower than that of the core pattern 22. The core pattern 22 has a plurality of cores 22 </ b> A each having an elongated shape and serving as a light propagation portion. Each core 22 </ b> A is surrounded by a clad 23. As a result, the core 22A is well protected, and the total reflection using the difference in refractive index between the core and the clad can be satisfactorily performed. Although there is no limitation in particular as a kind of optical waveguide, A quartz optical waveguide and a polymer optical waveguide are mentioned suitably.
The clad 23 includes a lower clad layer 23A and an upper clad layer 23B. The tapered optical waveguide 21 is formed by laminating a lower clad layer 23A, a core pattern 22, and an upper clad layer 23B on an optical waveguide substrate 24 in this order. It is sandwiched between the layers 23 </ b> A and 23 </ b> B and embedded in the clad 23.

Each core 22A is tapered, and its vertical cross-sectional area along the optical axis X is directed from one end (hereinafter referred to as a small diameter end 22B) to the other end (hereinafter referred to as a large diameter end 22C). Gradually increases. In the present embodiment, the optical axis X coincides with a straight line connecting the cross-sectional center of the small-diameter end 22B and the cross-sectional center of the large-diameter end 22C.
As shown in FIG. 2, each core 22A has, for example, a quadrangular cross section, and both the width and the thickness gradually increase from the small diameter end 22B toward the large diameter end 22C. Here, the bottom surface 22 </ b> D of the core 22 </ b> A is parallel to the optical waveguide substrate 24, while the upper surface 22 </ b> E of the core 22 </ b> A is an inclined surface that is inclined with respect to the optical waveguide substrate 24. Further, both side surfaces 22F and 22G of the core 22A are perpendicular to the optical waveguide substrate 24, and are inclined at the same angle symmetrically with respect to the optical axis X when viewed from above as shown in FIG. Surface. The small diameter end 22B and the large diameter end 22C of each core 22A extend to both end faces of the tapered optical waveguide 21, and the small diameter end 22B and the large diameter end 22C of the core 22A are respectively provided on both end faces of the tapered optical waveguide 21. Each will be placed.
The vertical cross-sectional shape of the core 22A with respect to the optical waveguide substrate 24 is preferably a rectangular shape because it is easy to form a core pattern, and the length of one side is 35 to 500 μm. It is more preferable because it can be realized.

  The angle formed with respect to the optical axis X of the inclined surface (upper surface 22A and both side surfaces 22F, 22G) of the core, that is, the taper angle is the difference in refractive index between the core 22A and the clad 23 and the optical coupling loss with the light emitting member 30. The taper angle is set appropriately in consideration of the amount and the spread angle of the light beam emitted from the light emitting member 30, but the taper angle is smaller than the spread angle of the light beam incident on the core 22A from the light emitting member 30. Good. Thereby, the angle reduction effect by reflection on the outer peripheral surface of the tapered optical path 19 can be expected.

The refractive index difference between the core 22A and the clad 23 may be appropriately determined depending on the taper angle and the light beam spread angle, but the refractive index difference is preferably 0.3 to 7% from the viewpoint of light confinement.
In the tapered optical path 19, the length of the optical path provided with the taper can be appropriately selected depending on the transmission loss when passing through the optical path and the taper angle, but if it is 100 μm to 20 mm, the shape control of the lens member 27 It is preferable because the entire optical member can be reduced in size and height. The length of the optical path refers to the length along the optical axis X.
The method for producing the optical waveguide is not particularly limited. For example, after forming a photosensitive core layer on the lower cladding layer and forming the core pattern by photolithography, the upper cladding layer and the upper surface of the core pattern are formed. The surface of the core pattern filled with the upper cladding layer is formed by covering the side surface, or forming a core-forming recess in the lower cladding layer, filling the recess with the core pattern-forming resin. It is obtained by making it by covering.
The method for forming the taper in the optical waveguide 21 is not particularly limited, and examples thereof include the method described in WO2012 / 070585 pamphlet.

The cross-sectional area of the tapered optical path 19 on the small diameter end 22B side may be appropriately selected depending on the area of the light emitting portion of the light emitting member 30, the spread angle of the light beam, and the distance between the small diameter end 22B and the light emitting member 30.
For example, as shown in FIG. 1, a second optical path (for example, an optical fiber 32) is used as the light emitting member 30, and light emitted from the other end of the second optical path is incident on the small diameter end 22B as will be described later. In this case, the cross-sectional area of the small diameter end 22B is preferably equal to or larger than the cross-sectional area of the other end of the second optical path from the viewpoint of reducing the optical coupling loss. And it is better if the cross section of the other end of the second optical path is included in the cross section of the small diameter end 22B. Note that the section on the small diameter end 22B side here refers to a section perpendicular to the optical axis of the second optical path, and the sectional area refers to the area of the section.
The cross-sectional area of the tapered optical path 19 on the large diameter end 22C side may be appropriately selected according to the diameter of the lens member 27, the light beam spread angle, the distance to the small diameter end 22B, and the taper angle. The cross-sectional area of 22C is preferably smaller than the projected area of the lens member 27 along the optical axis X, and is more preferably included in the lens member 27. This is because the spot diameter of the light beam on the lens member 27 is wider than the cross-sectional area (near field spot diameter) at the large diameter end 22C. It is better if the spot diameter of the light beam emitted from the large diameter end 22 </ b> C side is incident on the lens member 27.
The distance between the lens member 27 and the large-diameter end 22C of the tapered optical path 19 is not particularly limited, but is preferably within 250 μm because the optical member 20 can be downsized.
Note that one “cross-section” is included in the other “cross-section” when the two “cross-sections” are viewed along the optical axis direction. It is arranged inside the “cross section”. Further, in this specification, the “cross section” is a vertical cross section with respect to the optical axis unless otherwise specified, and the cross sectional area means the area of the “cross section”.

(Light emitting member)
The light emitting member 30 is disposed on the optical axis X extending from the small diameter end 22B side of the tapered optical path 19.
The type of the light emitting member 30 is not particularly limited as long as it is a member that emits a light beam. For example, a light emitting element such as a laser diode or an LED, and the light beam is propagated to the end portion of the light beam. And an optical path member (second optical path) such as an optical waveguide exemplified by a quartz optical fiber, a plastic optical fiber, and the like.
For example, in the optical device shown in FIG. 1, the quartz optical fiber 32 as the second optical path and the light emitting element 33 are arranged in this order from the one end 22 </ b> B side, and the quartz optical fiber 32 becomes the light emitting member 30. The light beam emitted from the light emitting element 33 enters from one end of the quartz optical fiber 32, passes through the quartz optical fiber 32, is emitted from the other end side, and the light beam emitted from the quartz optical fiber 32 is tapered. The light enters the optical waveguide 21. The quartz optical fiber 32 includes a core 32A and a clad 32B surrounding the outer periphery of the core 32A, and the core 32A serves as an optical path for propagating a light beam.
The light beam incident on the tapered optical waveguide 21 from the light emitting member 30 may be light other than parallel light, and the spread angle of the light beam is preferably 1 ° to 45 °. Here, the spread angle of the light beam refers to an angle formed by the center of the optical axis of the light beam and a light component (half-value width) having an intensity that is ½ of the output peak value of the light beam.

  The light beam incident on the tapered optical waveguide 21 from the light emitting member 30 is not particularly limited, but may be an optical signal or illumination light used for signal transmission. The wavelength is not particularly limited as long as it is a single wavelength or a plurality of wavelengths. However, the wavelength may be within a range that can be transmitted through the tapered optical path 19 and the lens member 27, and includes ultraviolet light, visible light, and infrared light. Is more preferable.

As shown in FIG. 1, when the second optical path (optical fiber 32) is provided, the distance between the second optical path and the tapered optical path 19 is not particularly limited, but if the distance is 150 μm or less, The optical coupling loss with the tapered optical path 19 can be reduced, and more preferably, the other end of the second optical path is in close contact with the small diameter end 22B.
The shape of the cross section perpendicular to the optical axis of the second optical path is preferably constant from one end to the other end. When the shape is always constant and the area is constant, the light beam is propagated well. Therefore, it is more preferable. The shape may be a circle or a polygon, more preferably a circle or a rectangle.

  The lens member 27 and the light incident member 40 are arranged in this order on the optical axis X extending from the large diameter end 22C side of the tapered optical path 19, and the incident end surface and the light receiving surface of the light incident member 40 are connected to the lens member 27. It arrange | positions so that it may oppose.

(Lens member)
The lens member 27 is preferably fixed to one surface of the lens substrate 25, as shown in FIG. The other surface of the lens substrate 25 is fixed to the end surface of the tapered optical waveguide 21 via an adhesive layer 26, whereby the lens member 27 is arranged on the large diameter end 22 </ b> C side of the tapered optical waveguide 21. It is arranged on the optical axis X extended from.
In the present invention, the use of the lens substrate 25 is not essential, but it is preferable to provide the lens substrate 25 because a strong optical member 20 can be obtained. The lens substrate 25 only needs to have optical transparency with respect to the wavelength of the light beam to be used.
Further, the lens substrate 25 may not be light transmissive. In this case, a through hole may be formed at a position where the light beam is transmitted, and the lens member 27 may be formed on the through hole. If the lens substrate 25 is not provided, for example, the lens member 27 may be formed directly on the large-diameter end 22C of the core.

The lens member 27 is a condensing lens system that is transparent to the wavelength of the light beam that passes through the optical member 20 and has positive power. That is, the lens member 27 has a function of reducing or condensing the light beam spread angle, and is a member that can collect quasi-parallel light described later. The lens member 27 in the present embodiment is a half-convex lens having one surface that is a convex surface, more specifically, a plano-convex lens in which the other surface is a plane, and the plane side is fixed to the lens substrate 25. Therefore, the convex surface side of the plano-convex lens is disposed on the opposite side of the tapered optical path 19 along the optical axis.
The convex shape of the lens member 27 is not particularly limited as long as the divergence angle of the light beam can be reduced or condensed, but a cylindrical shape, a spherical shape, a Fresnel lens shape, or all cross sections passing through the optical axis. The shape may be a hyperbola type, a suspension type, or a quadratic curve type, and from the viewpoint of condensing the light beam at one point, a spherical shape, a Fresnel lens type, or all cross-sectional shapes passing through the optical axis are a hyperbola type, a suspension type. It is better if it is a type or a quadratic curve type.
The curvature of the lens member 27 is not particularly limited, but it is preferable that the focal length is 50 μm or more because it is easy to form and handle the lens, and if it is 3000 μm or less, the product can be easily downsized.
The thickness of the lens member 27 is not particularly limited as long as the above focal length is obtained. Further, the diameter of the lens member 27 may be appropriately set according to the diameter of the large diameter end 22C as described above.
The method of forming the lens member 27 is not particularly limited. For example, the lens member 27 is formed into a lens sheet having the lens member 27 by intaglio printing or injection molding, or a lens-forming resin composition to be described later is formed on the support substrate. It is preferable that the cylindrical resist is formed by lithography and the lens member 27 is formed by heating and melting.

(Light incident member)
The light incident member 40 is not particularly limited, and examples thereof include a light receiving element such as a photodiode, a light beam projection plate, or an optical path member composed of an optical waveguide, an optical fiber such as a quartz optical fiber, and a plastic optical fiber. It is done. In the optical device of FIG. 1, an example of a light receiving element 43 is shown as the light incident member 40.
From the viewpoint of efficiently performing lens functions such as condensing, the light incident member 40 has a light receiving surface of the light receiving element 43 and an incident end surface of the optical path member disposed at a distance of 10 μm to 10 mm from the surface of the lens member 27. It is more preferably 10 μm to 350 μm from the viewpoint of size reduction and height reduction.

(substrate)
There is no restriction | limiting in particular as a kind of board | substrate used for the lens board | substrate 25 and the board | substrate 24 for optical waveguides, For example, a glass epoxy resin board | substrate, a glass substrate, a silicon substrate, a plastic substrate, a board | substrate with a resin layer, a board | substrate with a metal layer, Examples thereof include a plastic film, a plastic film with a resin layer, a plastic film with a metal layer, and an electric wiring board provided with electric wiring. In addition, as the substrate, it is preferable to use a polyamide, polyamideimide, or polyimide substrate, more preferably from the viewpoint of flexibility and toughness and the ability to transmit light on the long wavelength side such as an optical signal. A polyimide substrate is preferred. The thickness of the substrate may be, for example, a thickness that can secure the distance between the lens member 27 and the large-diameter end 22C of the tapered optical path, and is 10 μm to 50 μm from the viewpoint of toughness and downsizing / reducing the height. Is preferred.

  Next, the effect | action of this embodiment is demonstrated using FIG. 4, the light emitting element 33 is used as the light emitting member 30, the light receiving element 43 is used as the light incident member 40, and the lens member 27 is directly formed on the end surface of the large diameter end 22C of the core 22A. Will be described. FIG. 4 shows only the core 22 </ b> A constituting the tapered optical path 19 in the tapered optical waveguide 21.

As shown in FIG. 4, the light beam incident on the small diameter end 22B side of the tapered optical path (core 22A) from the light emitting member 30 is light having a spread angle, while the tapered angle of the tapered optical path is The angle is smaller than the spread angle of the incident light beam. Therefore, of the light beam incident from the small diameter end 22B, the component having a large spread angle is reflected by the outer peripheral surface (the bottom surface 22D, the upper surface 22E, and the both side surfaces 22F, 22G) of the tapered optical path 19, and the large diameter end 22C. Propagated to the side. The reflected light beam accumulates the number of times it is reflected by the inclined surface, whereby the spread angle of the light beam upon incidence gradually decreases and approaches parallel light (hereinafter referred to as quasi-parallel light). The quasi-parallel light is incident on the lens member 27, collected by the lens member 27, and received by the light incident member 40 (light receiving element 43).
As described above, in the present embodiment, the light beam is gradually spread in the tapered optical path 19 and is gradually reduced in angle, and is incident on the lens member 27 as quasi-parallel light. Light that is not incident on the member 27 is less likely to be generated. In addition, since the light beam having a divergence angle is converted into a quasi-parallel light by the tapered optical path 19, the distance from the lens member 27 to the light incident member 40 is shortened, or the curvature of the lens member 27 is decreased. However, it becomes easy for light to enter the light incident member 40 appropriately. In addition, since the quasi-parallel light having a small spot diameter is condensed and made incident on the light incident member 40, the alignment tolerance of the light incident member 40 is easily increased.
In the present embodiment, the light receiving surface of the light receiving element that constitutes the light incident member 40 and various optical paths are located several μm to several tens of μm before or behind the point where the light beam is collected by the lens member 27. When the incident end face or the like is installed, the alignment tolerance of the light incident member 40 is improved.

On the other hand, for example, as shown in FIG. 9, when a normal optical waveguide 21 ′ having a constant cross-sectional area is used without using a tapered optical path, the light beam from the light emitting member 30 ′ has a spread angle. Is incident on the lens member 27 '. Therefore, the spot diameter of the light beam emitted from the optical waveguide 21 ′ increases as it approaches the lens member 27 ′, and a light beam component that is not incident on the lens member 27 ′ is likely to be generated. Further, when trying to condense a light beam having such a divergence angle with the lens member 27 ′, the lens is used to increase the distance to condensing or shorten the distance to condensing as shown in FIG. It is necessary to increase the curvature of the member 27 '. Furthermore, there is a problem that light cannot be condensed when the spread angle of the light beam is increased.
On the other hand, when only a tapered optical path is used without using a lens member, when the quasi-parallel light is emitted from the large-diameter end of the tapered optical path, the spot diameter is enlarged. There is a problem that it is difficult to reduce the optical loss.

Next, a second embodiment will be described with reference to FIG. FIG. 5 shows an optical device according to the second embodiment. Hereinafter, the second embodiment will be described with a focus on differences from the first embodiment, and the description of the second embodiment is the same as that of the first embodiment.
The optical member 20 according to the second embodiment has the same configuration as that of the first embodiment, and is a tapered optical waveguide 21 and a lens member disposed on the optical axis X extending from the large diameter end 22C side. 27.
On the other hand, unlike the first embodiment, in the present embodiment, the light emitting member 30 is disposed on the optical axis X extending from the large-diameter end 22C side, and on the optical axis X extending from the small-diameter end 22B side. The light incident member 40 is disposed on the surface.
The light emitting member 30 and the light incident member 40 are the same as those in the first embodiment. However, in the example of FIG. 5, the optical fiber as the second optical path is provided on the small diameter end 22B side. 32 and the light receiving element 43 are arranged in this order. The optical fiber 32 (second optical path) constitutes the light incident member 40, and the light beam emitted from the small diameter end 22 </ b> B is received by the light receiving element 43 through the optical fiber 32.
A light emitting element 33 as the light emitting member 30 is disposed at a position facing the lens member 27. The light emitting member 30 has a light emitting surface of the light emitting element 33 and an emitting end surface of the optical path member disposed at a distance of 10 μm to 10 mm from the surface of the lens member 27 from the viewpoint of efficiently performing lens functions such as condensing. It is more preferably 10 μm to 350 μm from the viewpoint of size reduction and height reduction.

In the second embodiment, the taper angle of the tapered optical path 19 may be an angle that does not become an angle at which the light beam incident on the tapered optical path 19 repeatedly reflects and leaks to the clad 23. It is preferable that the angle is 4 °.
Further, in the tapered optical path 19 of the second embodiment, the portion where the light beam incident from the lens member 27 is reflected at least once is preferably tapered, and the portion where the light beam is reflected first is tapered. It is even better if it is configured as follows. Therefore, for example, a normal optical waveguide having a constant cross-sectional area may be connected to the large-diameter end 22C of the tapered optical waveguide 21. The optical waveguide having a constant cross-sectional area may be integrated with the tapered optical waveguide 21 or may be provided as a separate member.
Further, in the second embodiment, the cross-sectional area of the small diameter end 22B of the tapered optical path 19 is the light receiving area of the light receiving element 43 constituting the light incident member 40, the light beam spread angle, the small diameter end 22B and the light incident member. What is necessary is just to select suitably by 40 distances and a taper angle.
When the second optical path is used as the light incident member 40 and light emitted from the small diameter end 22B is incident on the incident end of the second optical path, the cross-sectional area of the incident end of the second optical path is the small diameter end. The cross-sectional area of 22B or more is good, and the cross-section of the small-diameter end 22B is better if it is included in the incident end of the second optical path. Note that the section on the small diameter end 22B side here refers to a section perpendicular to the optical axis of the second optical path, and the sectional area refers to the area of the section.
The cross-sectional area of the large-diameter end 22C may be appropriately selected according to the diameter of the lens member 27, the light beam divergence angle, the distance to the small-diameter end 22B, and the taper angle. It is preferable that the size of the member 27 is included. The diameter of the lens member 22 is preferably such that all light rays can enter the lens member 22 when the light beam enters the lens member 27 from the light emitting member 30.
Furthermore, it is preferable that the distance between the lens member 27 and the large diameter end 22C of the tapered optical path 19 is within 5 mm because the optical member 20 can be downsized.

  Next, the effect | action of this embodiment is demonstrated using FIG. In the example of FIG. 6, the light emitting element 33 is used as the light emitting member 30, the light receiving element 43 is used as the light incident member 40, and the lens member 27 is directly formed on the end face of the large diameter end 22C. It explains using. FIG. 6 shows only the core 22 </ b> A constituting the tapered optical path 19 in the tapered optical waveguide 21.

In the present embodiment, as shown in FIG. 6, the light beam from the light emitting member 30 is incident from the lens member 27 side. The incident light beam is light having a divergence angle, but the divergence angle is reduced by the lens member 27 and is propagated through the tapered optical path 19. At this time, the light beam is propagated to the small diameter end 22B side in the tapered optical path 19 while the spot diameter is reduced.
Here, it is preferable that the lens member 27 can reduce the divergence angle of the incident light beam and can collect light within the tapered optical path 19 as shown in FIG. In this way, when the light beam is propagated through the tapered optical path 19 while being reduced in its divergence angle and condensed by the lens member 27, the incident angle of the light beam on the core-cladding interface during light propagation is small. Thus, the light beam can propagate to the small diameter end 22B without leaking into the cladding. Further, since the number of reflections can be reduced, light propagation is possible with low loss.
Furthermore, in the present embodiment, the tapered optical path 19 has an incident end on the large diameter end 22C side, and therefore can receive the light beam without loss even when the spot diameter of the light beam is large. Therefore, it is not necessary to increase the distance between the lens member 27 and the large diameter end 22C for condensing the light beam, and the optical device can be downsized.
Furthermore, the light beam component that could not be collected by the lens member 27 is reflected by the outer peripheral surface of the optical path 19, and the light beam can be efficiently propagated to the light incident member 40 on the small diameter end 22B side. Further, even if the light emitting member 30 is displaced in the direction perpendicular to the optical axis and the light condensing position on the small diameter end 22B side is slightly displaced, the light beam is reflected by using the reflection on the outer peripheral surface of the tapered optical path 19. Since the light is guided to the small diameter end 22B, light propagation loss and the like are reduced. Therefore, the alignment tolerance of the light emitting member 30 can be increased.

  On the other hand, as shown in FIG. 10, by simply providing a lens member on the incident end side of a normal optical path, if the distance between the lens member and the incident end portion is not ensured, the alignment tolerance by focusing is improved. Since the effect of reducing the loss cannot be obtained, it is difficult to reduce the size of the entire device. On the other hand, when a light beam having a divergence angle is directly incident on the tapered optical path without using the lens member 27, the reflection angle of the light beam in the tapered optical path becomes large as described above with reference to FIGS. Or the light beam leaks out of the optical path, or the optical coupling with the light incident member deteriorates.

Further, as shown in FIG. 7, the light beam may be most condensed at the small-diameter end 22B or in the vicinity thereof. As a result, the optical signal with the spread angle reduced is propagated from the small diameter end 22B to the light incident member with the spot diameter reduced by the tapered optical path 19. When the light beam is collected on the nearer side than the small-diameter end 22B, it becomes a light beam having an angle larger than the spread angle at the time of incidence in the optical path during light propagation, and it is easy to leak out of the optical path. The diameter, curvature, refractive index, and the like of the lens member 27 may be appropriately adjusted so that the light is condensed near the small diameter end 22B.
Note that the vicinity of the small-diameter end 22B means that, for example, the optical path length of the tapered optical path 19 is 20% or less away from the small-diameter end 22B along the optical axis.

In the first and second embodiments, the example in which the optical waveguide is used as the tapered optical path has been described. However, another optical path member such as an optical fiber may be used. In the case of an optical fiber, the cross section perpendicular to the optical axis is preferably a circle. The method for forming the taper in the optical fiber is not particularly limited, but it can be formed by, for example, heat melting and stretching. An optical fiber having a circular cross section is likely to have a tapered surface whose entire outer peripheral surface is inclined at the same angle with respect to the optical axis. Since the optical path can be a rotating body with the optical axis as the center, light propagation can be performed more smoothly. Note that the inclination angle of the tapered surface is preferably the same as that of the optical waveguide.
In addition, the cross-sectional shape of the optical waveguide or the optical fiber constituting the tapered optical path is not limited to a square or a circle, and may have other shapes.
However, it is preferable to use an optical waveguide as the tapered optical path and to have a square cross section as described above because a square core pattern can be easily formed using a dry film.
Further, the above-described core having a square cross section has both the height and the width of the core gradually increased toward the large diameter end 22C, but only one of the cores gradually increases toward the large diameter end 22C. Good.
In addition to the both side surfaces and the upper surface, the bottom surface of the core may be an inclined surface. Furthermore, at least one of the side surfaces, the bottom surface, and the top surface may be an inclined surface. Moreover, when both the side surfaces 22F and 22G of the core 22A are inclined, these two side surfaces may not be symmetrical.

As the type of optical fiber used for the tapered optical path 19, an optical fiber including a core and a clad having a refractive index lower than that of the core surrounding the core may be used, and a coating for protecting the optical fiber is provided on the outer peripheral surface of the clad. You may have. As a kind of optical fiber, a quartz optical fiber and a plastic optical fiber are mentioned suitably. The vertical cross-sectional shape of the core with respect to the optical axis is preferably a circle, and the diameter of 35 to 500 μm is more preferable because the optical member 20 can be reduced in size and height. The outer diameter of the cladding is not less than the diameter of the core and preferably not more than 2 mm. Specifically, the outer diameter of the clad is 125 μm, and the diameter of the core is generally 50 μm, 62.5 μm, 80 μm, or the like. The refractive index difference between the clad and the core may be appropriately selected according to the spread angle of the light beam introduced into the optical fiber, but is preferably 0.3 to 7%.
In addition, when an optical fiber is used as the light incident member and the light emitting member, the same optical fiber can be used.

Next, the optical device according to the third embodiment will be described in detail with reference to FIG.
In addition, the part which abbreviate | omitted description in the following description is the same as that of 1st Embodiment. Moreover, in FIG. 8, the member corresponding to each member of 1st Embodiment is shown with the referential mark which added 100 to the said referential mark.
In the present embodiment, the optical member 120 is further provided with an optical path conversion mirror 116. The optical path conversion mirror 116 is disposed on the optical axis between the tapered optical path 119 and the lens member 127, and transmission / reception of light between the optical path conversion mirror 116 and the lens member 127 is performed via the optical path conversion mirror 116.
Specifically, the tapered optical waveguide 121 including the tapered optical path 119 has a lower cladding layer 123A, a core pattern 122, and an upper portion on one surface of the optical waveguide substrate 124, as in the first embodiment. The clad layer 123B is laminated, and each core 122A is tapered. In the tapered optical waveguide 121, a groove 117 having a triangular cross section is formed from the first upper clad layer 123B side, and an optical path conversion mirror 116 including a core 122A is formed on an inclined surface constituting the side surface of the groove 117. The The groove 117 is formed by using, for example, a dicing saw or laser ablation.
The lens member 127 is formed on the other surface of the optical waveguide substrate 124, and the lens member 127 is disposed so as to face the optical path conversion mirror 116 with the optical waveguide substrate 124 interposed therebetween.
The large-diameter end 122C of the core 122A is the portion having the largest vertical cross-sectional area with respect to the optical axis, and is the side located closest to the small-diameter end 122B among the inclined surfaces formed in the tapered optical path 119 (core 122A). And a cross section perpendicular to the optical axis.

  The tapered optical path 119 is optically converted to the optical waveguide substrate 124 side (lower side) by the optical path conversion mirror 116, and the converted optical path is directed to the lens member 127. That is, the optical axis X of the optical member 120 is bent downward according to the inclination angle in the optical path conversion mirror 116 and passes through the lens member 127. Thereby, also in this embodiment, the lens member 127 is disposed on the optical axis extending from the large diameter end 122C.

Here, the optical path conversion mirror 116 may be inclined at 30 to 60 ° with respect to the optical axis, and the inclination angle is more preferably 40 to 50 °, further preferably 43 to 47 °, and most preferably 45 °. It is. If the inclination angle is 45 °, the optical axis is bent by about 90 ° by the optical path conversion mirror 16. Therefore, when the tilt angle is 45 °, the optical path conversion mirror 116 and the lens member 127 overlap each other when viewed from above.
The optical path conversion mirror 116 reflects using the refractive index difference between the refractive index (around 1.5) of the transparent member (core 122A) and the air layer, but a reflective metal film is formed on the mirror surface. May be formed. Preferred examples of the metal film include Au, Ag, Al, and the like because of the reflectance. The optical path conversion mirror 116 may be an optical path conversion mirror disposed as a separate member on the large diameter end 122C side of the tapered optical path 119.
When the optical path conversion mirror 116 is disposed as a separate member on the large-diameter end 122C side of the tapered optical path 119, for example, a method of arranging the above-described metal bumps having a 45 ° slope, or optical path conversion mirror formation For example, there is a method of forming a 45 ° slope using a dicing saw or laser ablation after the resin pattern is formed.

FIG. 8 shows an example in which a second optical path, specifically, an optical waveguide is used as the light emitting member 130. The optical waveguide of the light emitting member 130 is composed of a clad 136 composed of a lower clad layer 136A and an upper clad layer 136B, and a core pattern 137, like a tapered optical waveguide. The optical waveguide 135 of the light emitting member 130 is formed on the optical waveguide substrate 124. The lower clad layer 136A, the core pattern 137, and the upper clad layer 136B are the lower clad layer 123A of the tapered optical waveguide 121, the core pattern, respectively. 122 and the upper cladding layer 123B. Thus, when the tapered optical waveguide 121 and the optical waveguide 135 as the light emitting member 130 are formed on the same substrate, the members can be easily integrated and the manufacturing process can be simplified. Of course, the optical waveguide 135 of the light emitting member 130 may not be integrated with the tapered optical waveguide 121.
In the present embodiment, the light beam from the light emitting member 130 (the optical waveguide 135) is incident from the small diameter end 122B, reflected by the optical path conversion mirror 116, and the light incident member 40 (the light receiving element 43) via the lens member 127. ).

In the third embodiment, an optical fiber such as a quartz optical fiber or a plastic optical fiber may be used as the tapered optical path 119. In this case, the optical path conversion is performed on the large diameter end 122C side of the tapered optical path 119. A mirror may be formed.
In the present embodiment, it is not essential to use the optical waveguide substrate 124. However, as described above, the tapered optical waveguide 121 is disposed on one surface of the optical waveguide substrate 124 so that the optical waveguide substrate 124 It is preferable to provide the lens member 127 on the other surface because a strong optical member can be obtained. Similarly to the above, the optical waveguide substrate 124 only needs to be light transmissive with respect to the wavelength of the light beam. If the optical waveguide substrate 124 is not transmissive, a through hole is formed at a position where the light beam is transmitted. The lens member 127 may be formed on the through hole.

  Further, as in the second embodiment, the light emitting member is disposed on the optical axis extending from the large diameter end side, and the light incident member is disposed on the optical axis extending from the small diameter end side. It is possible to form an optical path conversion mirror on the optical member. In this case, the configuration of the optical member is the same as described above, and is omitted. In this case, the light beam emitted from the light emitting member is incident on the optical path conversion mirror via the lens member, is optically converted by the optical path conversion mirror, and is propagated from the small diameter end side to the light incident member.

  In addition, the optical members 20 and 120 of each said embodiment may be provided in an optical device, for example, the optical members 20 and 120 may be connected to the both ends of the above-mentioned 2nd optical path, respectively.

In each of the above embodiments, the lens-forming resin composition for forming the lens member is not particularly limited, and examples thereof include the following.
(Lens forming resin composition)
The resin composition for forming a lens may be a photosensitive resin composition. For example, (a) a binder polymer, (b) a photopolymerizable unsaturated compound having an ethylenically unsaturated group, and (c) an actinic ray. And a photopolymerization initiator that generates free radicals. By using such a photosensitive resin composition, the resolution and adhesion of the photosensitive layer can be improved and the light transmittance of the lens member 27 can be more reliably ensured, so that the optical performance and productivity of the lens member 27 can be improved. Furthermore, both can be achieved at a high level.

  (A) As a binder polymer, a vinyl copolymer (a1) is mentioned, for example, Specifically, what was obtained by polymerizing the following vinyl monomer is mentioned. For example, (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, ( N-butyl (meth) acrylate, iso-butyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, ( Heptyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, tetradecyl (meth) acrylate, Hexadecyl (meth) acrylate, octadecyl (meth) acrylate, Eiko (meth) acrylate , Docosyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, (meth) acrylic acid Methoxyethyl, methoxydiethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 2-hydroxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, Diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 2-fluoroethyl (meth) acrylate, 2-cyanoethyl (meth) acrylate, styrene, α-methyls Tylene, cyclohexylmaleimide, dicyclopentanyl (meth) acrylate, vinyl toluene, vinyl chloride, vinyl acetate, N-vinyl pyrrolidone, butadiene, isoprene, chloroprene, (meth) acrylamide, (meth) acrylonitrile and the like. These may be polymerized singly or in combination of two or more.

  Further, in the lens-forming resin composition of the present embodiment, (a) as a binder polymer, for example, a vinyl copolymer having a functional group such as a carboxyl group, a hydroxyl group, an amino group, an isocyanate group, an oxirane ring, and an acid anhydride. It has at least one ethylenically unsaturated group and one functional group such as an oxirane ring, an isocyanate group, a hydroxyl group, and a carboxyl group that reacts with and binds to the functional group of the vinyl copolymer. A radical polymerizable copolymer (a2) having an ethylenically unsaturated group in the side chain obtained by addition reaction of the compound can also be used.

  Examples of the vinyl monomer used in the production of the vinyl copolymer having a functional group such as a carboxyl group, a hydroxyl group, an amino group, an oxirane ring, and an acid anhydride include (meth) acrylic acid, maleic acid, and fumaric acid. , Itaconic acid, cinnamic acid, 2-hydroxyethyl (meth) acrylate, (meth) acrylamide, ethyl methacrylate, glycidyl (meth) acrylate, maleic anhydride and the like. These may be polymerized singly or in combination of two or more. Moreover, the said vinyl monomers other than the vinyl monomer which has functional groups, such as a carboxyl group, a hydroxyl group, an amino group, an oxirane ring, and an acid anhydride, can be copolymerized as needed.

  Furthermore, (a) the binder polymer can be obtained, for example, by copolymerizing a sulfur-containing compound represented by the following general formula (I) with an unsaturated carboxylic acid and / or an unsaturated carboxylic acid anhydride. A sulfur-containing copolymer (a3) may be used.

In the formula (I), R ¹ represents a hydrogen atom, an alkyl group which may have a substituent, an aralkyl group which may have a substituent or an aryl group which may have a substituent, R ² represents a hydrogen atom or a methyl group, A represents a divalent organic group, X ¹ and X ² each independently represent a sulfur atom or an oxygen atom, and at least one of X ¹ and X ² is a sulfur atom It is.
The sulfur-containing compound represented by the general formula (I) is a (meth) acrylic acid ester compound, and is characterized by containing a sulfur atom.

When R ¹ is an alkyl group which may have a substituent, examples of the substituent include an alkoxy group, an aralkyloxy group, an aryloxy group, an aryloxyalkyloxy group, an alkylthio group, an aralkylthio group, and an arylthio group. Groups and arylthioalkylthio groups. When R ¹ is an aralkyl group which may have a substituent, or an aromatic residue which may have a substituent, examples of the substituent include an alkyl group, an alkoxy group and an aryl group. Aralkyloxy group, aryloxy group, aryloxyalkyloxy group, alkylthio group, aralkylthio group, arylthio group, arylthioalkylthio group and halogen atom.

Examples of R ¹ include a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, and an n-hexyl group. Linear, branched or cyclic alkyl groups such as heptyl group, octyl group, cyclohexyl group, cyclohexylmethyl group, benzyl group, 4-methylbenzyl group, 4-chlorobenzyl group, 4-bromobenzyl group, β-phenyl Substituted or unsubstituted aralkyl groups such as ethyl group, phenyl group, 4-methylphenyl group, 3-methylphenyl group, 2-methylphenyl group, 4-methoxyphenyl group, 3-methoxyphenyl group, 2-methoxyphenyl group 4-phenylphenyl group, 4-phenoxyphenyl group, 3-phenoxyphenyl group, 2-phenoxyphenyl group, 4-methylthiophenyl group, 3-methylthiophenyl group, 2-methylthiophenyl group, 4-chlorophenyl group, 3-chlorophenyl group, 2-chlorophenyl group, 4-bromophenyl group, 3-bromophenyl group, 2-bromophenyl group , Α-naphthyl group, β-naphthyl group and the like substituted or unsubstituted aryl groups. From the viewpoint of increasing transparency and refractive index, R ¹ is preferably a substituted or unsubstituted aralkyl group or a substituted or unsubstituted aryl group.
Specifically, A is preferably an alkylene group having 1 to 10 carbon atoms which may contain an oxygen atom or a sulfur atom, and more preferably an alkylene group having 2 to 5 carbon atoms. Moreover, it is preferable that X < ¹ > and X < ² > are sulfur atoms from a viewpoint of making a refractive index higher.

Examples of the sulfur-containing compound represented by the general formula (I) include 1-thiomethyl-2- (meth) acryloylthiomethane, 1-thiomethyl-2- (meth) acryloylthioethane, 1-thiomethyl-2- ( (Meth) acryloylthio-n-propane, 1-thiomethyl-2- (meth) acryloylthio-n-butane, 1-thiomethyl-2- (meth) acryloylthio-n-pentane, 1-thiomethyl-2- (meth) Acryloylthio-n-hexane, 1-thioethyl-2- (meth) acryloylthio-n-heptane, 1-thioethyl-2- (meth) acryloylthio-n-octane, 1-thioethyl-2- (meth) acryloylthio Methane, 1-thioethyl-2- (meth) acryloylthioethane, 1-thioethyl-2- (meth) acryloylthio n-propane, 1-thioethyl-2- (meth) acryloylthio-n-butane, 1-thioethyl-2- (meth) acryloylthio-n-pentane, 1-thioethyl-2- (meth) acryloylthio-n- Hexane, 1-thioethyl-2- (meth) acryloylthio-n-heptane, 1-thioethyl-2- (meth) acryloylthio-n-octane, 1-thio-n-propyl-2- (meth) acryloylthiomethane 1-thio-n-propyl-2- (meth) acryloylthioethane, 1-thio-n-propyl-2- (meth) acryloylthio-n-propane, 1-thio-n-propyl-2- (meth) ) Acryloylthio-n-butane, 1-thio-n-propyl-2- (meth) acryloylthio-n-pentane, 1-thio-n-propyl-2- ( T) acryloylthio-n-hexane, 1-thio-n-propyl-2- (meth) acryloylthio-n-heptane, 1-thio-n-propyl-2- (meth) acryloylthio-n-octane, 1 -Thio-n-butyl-2- (meth) acryloylthiomethane, 1-thio-n-butyl-2- (meth) acryloylthioethane, 1-thio-n-butyl-2- (meth) acryloylthio-n -Propane, 1-thio-n-butyl-2- (meth) acryloylthio-n-butane, 1-thio-n-butyl-2- (meth) acryloylthio-n-pentane, 1-thio-n-butyl 2- (meth) acryloylthio-n-hexane, 1-thio-n-butyl-2- (meth) acryloylthio-n-heptane, 1-thio-n-butyl-2- (meth) acryloylthio -N-octane, 1-thiobenzyl-2- (meth) acryloylthiomethane, 1-thiobenzyl-2- (meth) acryloylthioethane, 1-thiobenzyl-2- (meth) acryloylthio-n-propane, 1-thiobenzyl 2- (meth) acryloylthioisopropane, 1-thiobenzyl-2- (meth) acryloylthio-n-butane, 1-thiobenzyl-2- (meth) acryloylthioisobutane, 1-thiobenzyl-2- (meth) acryloyl Thio-n-pentane, 1-thiobenzyl-2- (meth) acryloylthioisopentane, 1-thiobenzyl-2- (meth) acryloylthio-n-hexane, 1-thiobenzyl-2- (meth) acryloylthio-n-heptane 1-thiobenzyl-2- (meth) acryloylthio-n-oct 1-thio- (4′-methylbenzyl) -2- (meth) acryloylthiomethane, 1-thio- (4′-methylbenzyl) -2- (meth) acryloylthioethane, 1-thio- (4 '-Methylbenzyl) -2- (meth) acryloylthio-n-propane, 1-thio- (4'-methylbenzyl) -2- (meth) acryloylthioisopropane, 1-thio- (4'-methylbenzyl) ) -2- (Meth) acryloylthio-n-butane, 1-thio- (4′-methylbenzyl) -2- (meth) acryloylthioisobutane, 1-thio- (4′-methylbenzyl) -2- ( (Meth) acryloylthio-n-pentane, 1-thio- (4′-methylbenzyl) -2- (meth) acryloylthioisopentane, 1-thio- (4′-methylbenzyl) -2- (meth) acryloyl Thio-n-hexane, 1-thio- (4′-methylbenzyl) -2- (meth) acryloylthio-n-heptane, 1-thio- (4′-methylbenzyl) -2- (meth) acryloylthio- n-octane, 1-thio- (4′-methylthiobenzyl) -2- (meth) acryloylthiomethane, 1-thio- (2′-methylthiobenzyl) -2- (meth) acryloylthioethane, 1-thio- (3'-methylthiobenzyl) -2- (meth) acryloylthioethane, 1-thio- (4'-methylthiobenzyl) -2- (meth) acryloylthioethane, 1-thio- (4'-methylthiobenzyl)- 2- (meth) acryloylthio-n-propane, 1-thio- (4′-methylthiobenzyl) -2- (meth) acryloylthioisopropane, 1-thio- (4′-methylthio) Benzyl) -2- (meth) acryloylthio-n-butane, 1-thio- (4′-methylthiobenzyl) -2- (meth) acryloylthioisobutane, 1-thio- (4′-methylthiobenzyl) -2- (Meth) acryloylthio-n-pentane, 1-thio- (4′-methylthiobenzyl) -2- (meth) acryloylthioisopentane, 1-thio- (4′-methylthiobenzyl) -2- (meth) acryloylthio -N-hexane, 1-thio- (4'-methylthiobenzyl) -2- (meth) acryloylthio-n-heptane, 1-thio- (4'-methylthiobenzyl) -2- (meth) acryloylthio-n -Octane, 1-thio- (4'-methyloxybenzyl) -2- (meth) acryloylthiomethane, 1-thio- (4'-methyloxybenzyl) -2- (Meth) acryloylthioethane, 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloylthio-n-propane, 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloyl Thioisopropane, 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloylthio-n-butane, 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloylthioisobutane 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloylthio-n-pentane, 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloylthioisopentane, Thio- (4′-methyloxybenzyl) -2- (meth) acryloylthio-n-hexane, 1-thio- (4′-methyloxybenzyl) -2- (meth) Acryloylthio-n-heptane, 1-thio- (4′-methyloxybenzyl) -2- (meth) acryloylthio-n-octane, 1-thio- (4′-chlorobenzyl) -2- (meth) acryloylthio Ethane, 1-thio- (4′-bromobenzyl) -2- (meth) acryloylthioethane, 1-thio- (4′-phenylethylbenzyl) -2- (meth) acryloylthioethane, 1-thiophenyl-2 -(Meth) acryloylthiomethane, 1-thiophenyl-2- (meth) acryloylthioethane, 1-thiophenyl-2- (meth) acryloylthio-n-propane, 1-thiophenyl-2- (meth) acryloylthioisopropane 1-thiophenyl-2- (meth) acryloylthio-n-butane, 1-thiophenyl-2- (meth) acryloyl Thioisobutane, 1-thiophenyl-2- (meth) acryloylthio-n-pentane, 1-thiophenyl-2- (meth) acryloylthioisopentane, 1-thiophenyl-2- (meth) acryloylthio-n-hexane, 1- Thiophenyl-2- (meth) acryloylthio-n-heptane, 1-thiophenyl-2- (meth) acryloylthio-n-octane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthiomethane 1-thio- (2′-methylphenyl) -2- (meth) acryloylthioethane, 1-thio- (3′-methylphenyl) -2- (meth) acryloylthioethane, 1-thio- (4 ′ -Methylphenyl) -2- (meth) acryloylthioethane, 1-thio- (4'-methylphenyl) -2- (meth) acryloyl Thio-n-propane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthioisopropane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthio-n— Butane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthioisobutane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthio-n-pentane, 1-thio -(4'-methylphenyl) -2- (meth) acryloylthioisopentane, 1-thio- (4'-methylphenyl) -2- (meth) acryloylthio-n-hexane, 1-thio- (4'- Methylphenyl) -2- (meth) acryloylthio-n-heptane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthio-n-octane, 1-thio- (4′-methylthio) Enyl) -2- (meth) acryloylthiomethane, 1-thio- (2′-methylthiophenyl) -2- (meth) acryloylthioethane, 1-thio- (3′-methylthiophenyl) -2- (meth) Acryloylthioethane, 1-thio- (4′-methylthiophenyl) -2- (meth) acryloylthioethane, 1-thio- (4′-methylthiophenyl) -2- (meth) acryloylthio-n-propane, 1 -Thio- (4'-methylthiophenyl) -2- (meth) acryloylthioisopropane, 1-thio- (4'-methylthiophenyl) -2- (meth) acryloylthio-n-butane, 1-thio- ( 4'-methylthiophenyl) -2- (meth) acryloylthioisobutane, 1-thio- (4'-methylthiophenyl) -2- (meth) acryloylthio-n- Pentane, 1-thio- (4′-methylthiophenyl) -2- (meth) acryloylthioisopentane, 1-thio- (4′-methylthiophenyl) -2- (meth) acryloylthio-n-hexane, 1-thio -(4'-methylthiophenyl) -2- (meth) acryloylthio-n-heptane, 1-thio- (4'-methylthiophenyl) -2- (meth) acryloylthio-n-octane, 1-thio- ( 4′-methyloxyphenyl) -2- (meth) acryloylthiomethane, 1-thio- (4′-methyloxyphenyl) -2- (meth) acryloylthioethane, 1-thio- (4′-methyloxyphenyl) ) -2- (Meth) acryloylthio-n-propane, 1-thio- (4′-methyloxyphenyl) -2- (meth) acryloylthioisopropane, 1-thio -(4'-methyloxyphenyl) -2- (meth) acryloylthio-n-butane, 1-thio- (4'-methyloxyphenyl) -2- (meth) acryloylthioisobutane, 1-thio- (4 '-Methyloxyphenyl) -2- (meth) acryloylthio-n-pentane, 1-thio- (4'-methyloxyphenyl) -2- (meth) acryloylthioisopentane, 1-thio- (4'-methyl) Oxyphenyl) -2- (meth) acryloylthio-n-hexane, 1-thio- (4′-methyloxyphenyl) -2- (meth) acryloylthio-n-heptane, 1-thio- (4′-methyl) Oxyphenyl) -2- (meth) acryloylthio-n-octane, 1-thio- (4′-phenylphenyl) -2- (meth) acryloylthioethane, 1-thio- (4′- Phenyloxyphenyl) -2- (meth) acryloylthioethane, 1-thio- (4′-chlorophenyl) -2- (meth) acryloylthioethane, 1-thio- (4′-bromophenyl) -2- (meth) ) Acryloylthioethane,
1-thionaphthyl-2- (meth) acryloylthioethane, 1-thiomethyl-2- (meth) acryloyloxyethane, 1-thioethyl-2- (meth) acryloyloxyethane, 1-thio-n-propyl-2- ( (Meth) acryloyloxyethane, 1-thio-n-butyl-2- (meth) acryloyloxyethane, 1-thiobenzyl-2- (meth) acryloyloxyethane, 1-thio- (4′-methylbenzyl) -2- (Meth) acryloyloxyethane, 1-thio- (2′-methylthiobenzyl) -2- (meth) acryloyloxyethane, 1-thio- (3′-methylthiobenzyl) -2- (meth) acryloyloxyethane, 1 -Thio- (4'-methylthiobenzyl) -2- (meth) acryloyloxyethane, 1-thio- (4'-methyl) Xylbenzyl) -2- (meth) acryloyloxyethane, 1-thio- (4′-chlorobenzyl) -2- (meth) acryloyloxyethane, 1-thio- (4′-bromobenzyl) -2- (meth) Acryloyloxyethane, 1-thio- (4′-phenylethylbenzyl) -2- (meth) acryloyloxyethane, 1-thiophenyl-2- (meth) acryloyloxyethane, 1-thio- (2′-methylphenyl) 2- (meth) acryloyloxyethane, 1-thio- (3′-methylphenyl) -2- (meth) acryloyloxyethane, 1-thio- (4′-methylphenyl) -2- (meth) acryloylthio Ethane, 1-thio- (2′-methylthiophenyl) -2- (meth) acryloyloxyethane, 1-thio- (3′-methylthiophenyl) 2- (meth) acryloyloxyethane, 1-thio- (4′-methylthiophenyl) -2- (meth) acryloyloxyethane, 1-thio- (4′-methyloxyphenyl) -2- (meth) acryloyloxy Ethane, 1-thio- (4′-phenylphenyl) -2- (meth) acryloyloxyethane, 1-thio- (4′-phenyloxyphenyl) -2- (meth) acryloyloxyethane, 1-thio- ( 4'-chlorophenyl) -2- (meth) acryloyloxyethane, 1-thio- (4'-bromophenyl) -2- (meth) acryloyloxyethane, 1-thionaphthyl-2- (meth) acryloyloxyethane It is done. These can be used alone or in combination of two or more.

  There is no restriction | limiting in particular as unsaturated carboxylic acid and / or unsaturated carboxylic anhydride which are copolymerized with the sulfur containing compound represented by general formula (I), For example, (meth) acrylic acid, crotonic acid, 2 -Monocarboxylic acids such as acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, maleic acid, fumaric acid, citraconic acid, mesacone Examples thereof include dicarboxylic acids such as acid and itaconic acid, and dicarboxylic anhydrides such as maleic anhydride, fumaric anhydride, citraconic anhydride, mesaconic anhydride, and itaconic anhydride. These can be used alone or in combination of two or more.

  In addition to the sulfur-containing compound represented by the general formula (I) and the unsaturated carboxylic acid and / or unsaturated carboxylic acid anhydride, the sulfur-containing copolymer contains other unsaturated compounds as monomer units. You may go out.

  Other unsaturated compounds that may be included as monomer units in the sulfur-containing copolymer (a3) include sulfur-containing compounds represented by general formula (I), and unsaturated carboxylic acids and / or unsaturated carboxylic acids. If it is an unsaturated compound copolymerizable with an acid anhydride, there will be no restriction | limiting in particular. Specifically, various unsaturated compounds listed as vinyl monomers for obtaining the above vinyl copolymer (a1), and γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl- o-phthalate, β-hydroxyethyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, (meth) acrylic acid-2- Hydroxy-3-chloropropyl, o-phenylphenol glycidyl ether (meth) acrylate, (meth) acrylic acid-2-hydroxy-3-phenoxypropyl, (meth) acrylic acid-2-[(1,1′-biphenyl) Oxy] ethoxy, (meth) acrylic acid-2- (2-methoxyethoxy) ethyl, the number of oxyethylene groups is 2 A is 23 (meth) acrylic acid methoxy polyoxyethylene (meth) -2-phenoxyethyl acrylate, (meth) -2- acrylate (2-phenoxyethyl - oxy) ethyl, and the like. From the viewpoint of further improving the refractive index, it is preferable to copolymerize (meth) acrylic acid-2-[(1,1′-biphenyl) oxy] ethoxy as another unsaturated compound component. These can be used individually by 1 type or in combination of 2 or more types.

  (A) The weight average molecular weight of the binder polymer (measured by gel permeation chromatography and converted to standard polystyrene) is the heat resistance, heat meltability, coatability, and the microlens array photosensitive element described later. From the viewpoints of film properties (characteristics that maintain a film-like form), solubility in a solvent, solubility in a developing solution in the development step, and the like, it is preferably 1000 to 300000, and 5000 to 150,000. Is more preferable.

  Furthermore, it is preferable that (a) the binder polymer has an acid value so that it can be developed with various known developing solutions in the development step. For example, when the development is performed using an alkaline aqueous solution such as sodium carbonate, potassium carbonate, tetramethylammonium hydroxide, or triethanolamine, the acid value is preferably 50 to 260 mgKOH / g. By setting the acid value to 50 mgKOH / g or more, development tends to be easily performed. By setting the acid value to 260 mgKOH / g or less, the developer resistance (the portion that becomes a pattern without being removed by development is a developer solution). Tend to be better). Moreover, when developing using the aqueous alkali solution which consists of water or aqueous alkali solution and 1 or more types of surfactant, it is preferable that an acid value shall be 16-260 mgKOH / g. When the acid value is 16 mgKOH / g or more, the development tends to be easy, and when the acid value is 260 mgKOH / g or less, the developer resistance tends to be good.

(B) Photopolymerizable unsaturated compound having an ethylenically unsaturated group As the photopolymerizable unsaturated compound having an ethylenically unsaturated group, for example, a polyhydric alcohol and an α, β-unsaturated carboxylic acid are reacted. 2,2-bis (4- (di (meth) acryloxypolyethoxy) phenyl) propane, a compound obtained by reacting a glycidyl group-containing compound with an α, β-unsaturated carboxylic acid, urethane Monomer, nonylphenyldioxylene (meth) acrylate, γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyethyl-β ′-(meth) acryloyloxyethyl-o -Phthalate, β-hydroxypropyl-β '-(meth) acryloyloxyethyl-o-phthalate, (meth) acrylic acid Kill ester, and the like.

  Examples of the compound obtained by reacting the polyhydric alcohol with an α, β-unsaturated carboxylic acid include, for example, polyethylene glycol di (meth) acrylate having 2 to 14 ethylene groups and 2 propylene groups. ~ 14 polypropylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, trimethylolpropane diethoxytri (meth) acrylate , Trimethylolpropane triethoxytri (meth) acrylate, trimethylolpropanetetraethoxytri (meth) acrylate, trimethylolpropane pentaethoxytri (meth) acrylate, tetramethylolmethanetri (meth) ) Acrylate (pentaerythritol tri (meth) acrylate), tetramethylolmethane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate and the like.

  Examples of the 2,2-bis (4- (di (meth) acryloxypolyethoxy) phenyl) propane include 2,2-bis (4- (di (meth) acryloxydiethoxy) phenyl) propane, 2 , 2-bis (4- (di (meth) acryloxytriethoxy) phenyl) propane, 2,2-bis (4- (di (meth) acryloxypentaethoxy) phenyl) propane, 2,2-bis (4 -(Di (meth) acryloxydecaethoxy) phenyl) and the like.

  Examples of the compound obtained by reacting the glycidyl group-containing compound with an α, β-unsaturated carboxylic acid include trimethylolpropane triglycidyl ether tri (meth) acrylate and 2,2-bis (4- (meth)). (Acryloxy-2-hydroxy-propyloxy) phenyl and the like.

  Examples of the urethane monomer include (meth) acrylic monomers having an OH group at the β-position and isocyanate compounds such as isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1,6-hexamethylene diisocyanate. Addition reaction product, tris ((meth) acryloxytetraethylene glycol isocyanate) hexamethylene isocyanurate, ethylene oxide modified urethane di (meth) acrylate, ethylene oxide, propylene oxide modified urethane di (meth) acrylate and the like.

  Examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid 2-ethylhexyl ester, and the like. .

  Said photopolymerizable unsaturated compound can be used individually by 1 type or in combination of 2 or more types.

  When (a) the sulfur-containing copolymer (a3) is used as the binder polymer, (b) the photopolymerizable unsaturated compound having an ethylenically unsaturated group is (B1) an ethylenically unsaturated group. And (B2) a photopolymerizable compound having at least two ethylenically unsaturated groups.

  (B1) As a photopolymerizable unsaturated compound having one ethylenically unsaturated group, for example, γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyethyl- β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, (meth) acrylic acid-2-hydroxy-3-chloropropyl, o- Phenylphenol glycidyl ether (meth) acrylate, (meth) acrylic acid-2-hydroxy-3-phenoxypropyl, (meth) acrylic acid-2-[(1,1′-biphenyl) oxy] ethoxy, (meth) acrylic acid 2- (2-methoxyethoxy) ethyl, (meth) acrylic acid having 2 to 23 oxyethylene groups Acid methoxypolyoxyethylene, (meth) acrylic acid-2-phenoxyethyl, (meth) acrylic acid-2- (2-phenoxyethyl-oxy) ethyl, (meth) acrylic having 2 to 23 oxyethylene groups The acid phenoxy polyoxyethylene is mentioned. Among them, as the component (B1), from the viewpoint of further improving the refractive index, the number of (meth) acrylic acid-2-[(1,1′-biphenyl) oxy] ethoxy or oxyethylene groups is 2 to 5. (Meth) acrylic acid phenoxypolyoxyethylene is preferred. Moreover, the sulfur containing compound represented by the said general formula (I) can be used as (B1) component. Furthermore, the above-mentioned other unsaturated compounds can also be used as the component (B1). These compounds can be used individually by 1 type or in combination of 2 or more types.

(B2) Examples of the photopolymerizable unsaturated compound having at least two ethylenically unsaturated groups include compounds obtained by reacting polyhydric alcohols with α, β-unsaturated carboxylic acids, and glycidyl groups. Polyhydric thiols such as compounds obtained by reacting containing compounds with α, β-unsaturated carboxylic acids, urethane monomers, bis (4-methacryloylthiophenyl) sulfide, bis [(2-methacryloylthio) ethyl] sulfide, etc. A compound obtained by reacting an α, β-unsaturated carboxylic acid with α is preferably used.
These compounds exemplified as the component (B2) can be used singly or in combination of two or more.

(C) Photopolymerization initiator Examples of photopolymerization initiators that generate free radicals with actinic rays include benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), N, N′—. Tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)] (“Irgacure -OXE01 ", trade name of Ciba Specialty Chemicals Co., Ltd.), ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime ) (Irgacure-OXE02, Ciba Specialty Chemicals Co., Ltd. trade name), 2-benzyl-2-dimethylamino -1- (4-morpholinophenyl) -butan-1-one (“Irgacure-369”, trade name of Ciba Specialty Chemicals), 2-methyl-1- [4- (methylthio) phenyl] -2- Aromatic ketones such as morpholino-propan-1-one (“Irgacure-907”, Ciba Specialty Chemicals Co., Ltd.); 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1 , 2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphtho Quinones such as 2,3-dimethylanthraquinone; benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether and benzoin phenyl ether; benzoin compounds such as benzoin, methyl benzoin and ethyl benzoin; benzyl derivatives such as benzyl dimethyl ketal; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4 2,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, etc. 4,5-triarylimidazole dimer; 9- Examples include acridine derivatives such as phenylacridine and 1,7-bis (9,9′-acridinyl) heptane; N-phenylglycine, N-phenylglycine derivatives, and coumarin compounds.

  In the 2,4,5-triarylimidazole dimer, the substituents substituted with two 2,4,5-triarylimidazoles may be the same or different. Moreover, you may combine a thioxanthone type compound and a tertiary amine compound like the combination of diethyl thioxanthone and dimethylaminobenzoic acid.

In addition, from the viewpoint of adhesion and sensitivity in the photolithography process, 2,4,5-triarylimidazole dimer is preferable as the component (c), and 1 from the viewpoint of visible light transmittance when a microlens is used. , 2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)] is more preferable.
Said photoinitiator can be used individually by 1 type or in combination of 2 or more types.

  In the lens-forming resin composition, the blending ratio of the (a) binder polymer is preferably 20 to 90 parts by mass, and 30 to 85 parts by mass with respect to 100 parts by mass of the total amount of the components (a) and (b). More preferably, the content is 35 to 80 parts by mass, particularly preferably 40 to 75 parts by mass. When the blending ratio is 20 parts by mass or more, the coating property, heat melting property, or film property when a lens photosensitive element described later tends to be good, and by 90 parts by mass or less. , Photocurability or heat resistance tends to be good.

  In the lens-forming resin composition, the blending ratio of the photopolymerizable unsaturated compound (b) having an ethylenically unsaturated group is 10 to 10 parts by mass with respect to 100 parts by mass of the total amount of the components (a) and (b). It is preferably 80 parts by mass, more preferably 15 to 70 parts by mass, particularly preferably 20 to 65 parts by mass, and particularly preferably 25 to 60 parts by mass. When the blending ratio is 10 parts by mass or more, the photocurability or heat resistance tends to be good, and when it is 80 parts by mass or less, the coating property, the heat melting property, or the photosensitive element for a lens is obtained. There exists a tendency for film property to become favorable.

  In addition, in the photosensitive resin composition for a microlens array of the present embodiment, the blending ratio of the (c) photopolymerization initiator is 0.05 to It is preferably 20 parts by mass, more preferably 0.1 to 15 parts by mass, and particularly preferably 0.15 to 10 parts by mass. By making this blending ratio 0.05 parts by mass or more, photocuring tends to be good, and by 20 parts by mass or less, in the curing step, actinic rays on the surface irradiated with actinic rays of the photosensitive layer Absorption is prevented from increasing and internal photocuring is prevented from becoming insufficient.

  For the photosensitive resin composition for lenses, as necessary, adhesion imparting agents such as silane coupling agents, leveling agents, plasticizers, fillers, antifoaming agents, flame retardants, stabilizers, antioxidants, perfumes. , A thermal crosslinking agent, a polymerization inhibitor and the like can be contained. These can be used individually by 1 type or in combination of 2 or more types. Moreover, these compounding ratios can be 0.01-20 mass parts with respect to 100 mass parts of total amounts of (a) and (b) component, respectively.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to a following example, unless the summary is exceeded.

Example 1
[Production of optical member of FIG. 1]
[Production of lens member]
<Production of photosensitive element for lens>
A flask equipped with a stirrer, reflux condenser, inert gas inlet and thermometer was charged with 190 parts by mass of propylene glycol monomethyl ether acetate, heated to 80 ° C. in a nitrogen gas atmosphere, and the reaction temperature was raised to 80 ° C. 1. While maintaining, 10 parts by weight of methacrylic acid, 1 part by weight of n-butyl methacrylate, 74 parts by weight of benzyl methacrylate, 15 parts by weight of 2-hydroxyethyl methacrylate, and 2,2′-azobis (isobutyronitrile) 5 parts by mass were uniformly dropped over 4 hours. After completion of the dropping, stirring was continued at 80 ° C. for 6 hours to obtain a binder polymer (a) solution (solid content: 35% by mass) having a weight average molecular weight of about 30,000.
Next, 200 parts by mass (solid content: 70 parts by mass) of the binder polymer (a) solution (solid content 35% by mass) and 2,2-bis (4- (di (meth) acryloxypolyethoxy) phenyl) 8 parts by mass of propane, 22 parts by mass of β-hydroxyethyl-β ′-(meth) acryloyloxyethyl-o-phthalate, 2.1 parts by mass of 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, Add 0.33 parts by mass of N, N′-tetraethyl-4,4′-diaminobenzophenone, 0.25 parts by mass of mercaptobenzimidazole, 8 parts by mass of (3-methacryloylpropyl) trimethoxysilane, and 30 parts by mass of methyl ethyl ketone. Was mixed for 15 minutes to prepare a photosensitive resin composition solution for lenses.

  A polyethylene terephthalate film having a thickness of 16 μm was used as a support film, and the photosensitive resin composition solution for lenses obtained above was uniformly applied on the support film using a comma coater, and a hot air convection type at 100 ° C. The solvent was removed by drying for 3 minutes with a drier to form a lens-forming resin layer. The thickness of the obtained lens forming resin layer was 30 μm. Next, a polyethylene terephthalate film having a thickness of 25 μm was further bonded as a cover film on the obtained lens-forming resin layer to produce a lens photosensitive element.

<Production of substrate with lens member>
Next, while peeling the cover film of the photosensitive element for lenses on one surface of a polyimide film (polyimide; Upilex RN (manufactured by Ube Nitto Kasei Co., Ltd.), thickness: 25 μm) as a substrate 25, Using a laminator (manufactured by Hitachi Chemical Co., Ltd., trade name “HLM-1500”) so that the lens-forming resin layer is in contact, roll temperature is 120 ° C., substrate feed rate is 1 m / min, pressure bonding pressure (cylinder pressure) Lamination was performed under the condition of 4 × 10 ⁵ Pa, and a lens-forming resin layer with a support film was laminated on one surface of the substrate 25.

  Next, after peeling off the support film from the lens-forming resin layer, a lens photomask having an opening with an opening width = φ170 μm is disposed on one surface side of the substrate 25, and the light scattering sheet 43 is further disposed thereon. “Quilting Mylar” (manufactured by Nippon Chemtech Co., Ltd., trade name “Exposure Film EWS-88”) was laminated.

  Then, a parallel light exposure machine (Oak Manufacturing Co., Ltd., EXM1201) is passed through a light scattering sheet and a lens photomask with an ultraviolet exposure machine (model name: EXM-1172, manufactured by Oak Manufacturing Co., Ltd.). Were irradiated with ultraviolet rays. Thereafter, the support film was peeled off and etched using a 1.0% by mass aqueous solution of potassium carbonate to prepare a resist for lens formation. Subsequently, it heated at 180 degreeC for 1 hour, the lens formation resist was fuse | melted, and the lens member 27 which has a convex surface was obtained. The obtained lens member had a diameter of 170 μm, a height of 30 μm, and a curvature of 122 μm.

[Production of tapered optical path]
Following the method of Example 1 of the pamphlet of WO2012 / 070585, the following tapered optical waveguide 21 was produced. First, a 150 mm × 150 mm polyimide film (polyimide; Upilex RN (manufactured by Ube Nitto Kasei Co., Ltd.), thickness: 25 μm) as a substrate 24 and a lower cladding with a thickness (distance from the substrate surface to the bottom of the core pattern) of 30 μm Layer 23A was formed. Next, a tapered core pattern 22 composed of a core 22A having a small diameter end 22B having a width of 50 μm × height 50 μm and a large diameter end 22C having a width of 95 μm × height of 95 μm was formed on the lower clad layer 23A. Further thereon, an upper clad layer 23B having a thickness of 110 μm (distance from the lower clad layer surface to the upper clad layer upper surface) was formed, and a tapered optical waveguide 21 having a length of 3 mm was formed. The refractive index of the cladding was 1.49, and the refractive index of the core was 1.58.

[Bonding of tapered optical path and lens member]
5 μm of a clad layer-forming resin varnish is applied to the end face where the large-diameter end 22C of the optical waveguide 21 obtained above is disposed, and the substrate 25 with the lens member 27 is attached to the optical axis of the optical waveguide 21 and the lens member 27. 1 were aligned and pasted so that the lens centers were aligned, heated at 180 ° C. for 1 hour, and the optical waveguide 21 and the lens member 27 were joined to obtain the optical member 20 shown in FIG.

[Evaluation]
A GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 as the second optical path (light emitting member 30) is disposed at the small-diameter end 22B of the obtained optical member 20, and the 850 nm The optical signal was incident on the small diameter end 22B of the tapered optical path 19. The spot diameter of the optical signal emitted from the lens member 27 was most condensed at a position of 240 μm from the surface of the lens member 27. Next, when the light propagation loss from the second optical path to the most concentrated spot was measured using a photodiode having a light receiving portion with a diameter of 60 μm, it was 0.4 dB. When the photodiode was placed at a position 260 μm from the surface of the lens member 27, the light propagation loss was 0.43 dB, and when the photodiode was shifted 20 μm from the optical axis, it was 0.88 dB.

Example 2
In Example 1, the core pattern 22 has a small diameter end 22B having a width of 37 μm × height of 37 μm and a large diameter end 22C having a width of 105 μm × height of 105 μm. The member 20 was produced.
[Evaluation]
At the small diameter end 22B of the obtained tapered optical path 19, a GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 is disposed as the second optical path (light incident member 40), and light is emitted. As the member 30, a GI 50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 was arranged at a position 250 μm from the lens member, and an optical signal of 850 nm was incident on the lens member 27. The light propagation loss of the light emitted from the second optical path was 0.55 dB, and it was 0.75 dB when the optical fiber as the light emitting member 30 was shifted by 20 μm from the optical axis.

Comparative Example 1
In Example 1, an optical member was produced in the same manner except that the tapered core pattern was changed to a straight core pattern having a width of 50 μm and a height of 50 μm.
[Evaluation]
GI50 multimode quartz light with a numerical aperture (NA) = 0.2 as a second optical path (light emitting member) at one end (end where no lens member 27 is provided) of the obtained straight core pattern A fiber was placed, and an optical signal of 850 nm was incident on the small diameter end 22B. The spot diameter of the optical signal emitted from the lens member was not condensed. When the photodiode was placed at a position of 260 μm from the lens member surface, the light propagation loss was 1.22 dB.

Comparative Example 2
In Example 1, an optical member was produced in the same manner except that the taper core pattern was reversed in the direction of taper and the lens member was joined to the end face on the small diameter end side of the optical waveguide.
[Evaluation]
A GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 is arranged as the second optical path (light emitting member) at the large diameter end of the obtained tapered optical path, and an optical signal of 850 nm is obtained. Was incident on the large-diameter end of the tapered optical path. The spot diameter of the optical signal emitted from the lens member was not condensed. When the photodiode was placed at a position 260 μm from the lens member surface, the light propagation loss was 1.98 dB.

Comparative Example 3
In Example 2, an optical member was produced in the same manner except that the lens member was not formed.
[Evaluation]
As in Example 2, when an optical signal was incident on the large diameter end, the light propagation loss was 1.58 dB.

Comparative Example 4
In Example 2, an optical member was produced in the same manner except that the tapered core pattern was not formed.
[Evaluation]
A multimode quartz optical fiber having a numerical aperture (NA) = 0.2 is disposed as a second optical path (light incident member) at the same distance from the lens member as in the first embodiment, and light is emitted. As a member, a GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 was arranged at a position of 250 μm from the lens member, and an optical signal of 850 nm was incident on the lens member 27. The light propagation loss of the light emitted from the second optical path was 2.55 dB, and it was 2.99 dB when the optical fiber as the light emitting member was shifted by 20 μm from the optical axis.

Example 3
[Production of optical member of FIG. 8]
In accordance with the method of Example 1 of WO2012 / 07085, the second surface of the substrate 124 to which the lens member 127 obtained in Example 1 is fixed is opposite to the surface on which the lens member 127 is formed as follows. A tapered optical waveguide 121 formed integrally with the optical waveguide 135 as an optical path was formed. First, lower clad layers 123A and 136A having a thickness (distance from the substrate surface to the core pattern bottom surface) of 30 μm were formed on the opposite surface of the substrate. Next, a tapered core pattern 122 and a core pattern 137 having a length of 5 mm, a width of 50 μm and a height of 50 μm as a second optical path connected to the small-diameter end 122B side of the core pattern 122 on the lower clad layers 123A and 136A. And formed at the same time. Next, upper cladding layers 123B and 136B having a thickness of 110 μm (distance from the surface of the lower cladding layer to the upper surface of the upper cladding layer) were formed, and the tapered optical waveguide 121 and the second optical path were integrally formed.
[Formation of optical path conversion mirror]
Next, a V-shaped groove 117 was formed from the upper clad layer 123B side using a dicing saw (DAC552, manufactured by Disco Corporation), and an optical path conversion mirror 116 having an inclination angle of 45 ° was formed. The optical path conversion mirror 116 was at a position facing the lens member 127 with the substrate 124 interposed therebetween. The tapered core pattern 122 had a small-diameter end 122B having a width of 50 μm × height of 50 μm and a large-diameter end 122C having a width of 95 μm × height of 95 μm.
[Evaluation]
An optical signal of 850 nm was incident on the second optical path using a GI50 multimode silica optical fiber having a numerical aperture (NA) = 0.2. The spot diameter of the optical signal emitted from the lens member 27 was most condensed at a position of 230 μm from the surface of the lens member 127. Next, the light propagation loss from the second optical path to the most concentrated spot was measured using a photodiode having a light receiving portion with a diameter of 60 μm, and found to be 0.85 dB. When the photodiode was placed at a position 260 μm from the surface of the lens member 127, the light propagation loss was 0.90 dB, and when the photodiode was shifted 20 μm from the optical axis, it was 1.32 dB.

Example 4
In the tapered optical waveguide 121 of Example 3, the shape of the small diameter end 122B is 37 μm wide × 37 μm high, the shape of the large diameter end 122C is 105 μm wide × 105 μm high, and the shape of the second optical path is 37 μm wide × height. An optical member was produced in the same manner except that the thickness was 37 μm.
[Evaluation]
As the light emitting member 130, a GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 is arranged at a position 250 μm from the lens member, and an optical signal of 850 nm is incident on the lens member 127. . The light propagation loss of the light emitted from the second optical path (optical waveguide 135) was 1.02 dB, and was 1.11 dB when the optical fiber as the light emitting member 130 was shifted by 20 μm from the optical axis. .

Comparative Example 5
In Example 3, an optical member was produced in the same manner except that the tapered core pattern was changed to a straight core pattern having a width of 50 μm and a height of 50 μm.
[Evaluation]
Using the GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 from one end (end where no lens member is provided) to the obtained straight core pattern, an optical signal of 850 nm is used. Was incident. The spot diameter of the optical signal emitted from the lens member was not condensed. When the photodiode was placed at a position 260 μm from the lens member surface, the light propagation loss was 2.03 dB.

Comparative Example 6
In Example 3, an optical member was produced in the same manner except that the taper core pattern was reversed in the direction of taper, while the cross-sectional shape of the second optical path was left 50 μm × height 50 μm. .
[Evaluation]
A 850 nm optical signal was incident from the second optical path end using a GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2. The spot diameter of the optical signal emitted from the lens member was not condensed. When the photodiode was placed at a position 260 μm from the surface of the lens member 27, the light propagation loss was 2.76 dB.

Comparative Example 7
In Example 4, an optical member was produced in the same manner except that the lens member 127 was not formed.
[Evaluation]
When an optical signal was incident on the large-diameter end from the same position as in Example 4, that is, from the surface opposite to the optical waveguide formation surface of the substrate, the optical propagation loss was 2.29 dB.

Comparative Example 8
In Example 4, an optical member was produced in the same manner except that the tapered core pattern was not formed and the optical waveguide was formed only by the second optical path.
[Evaluation]
A GI50 multimode quartz optical fiber having a numerical aperture (NA) = 0.2 was placed at a position 250 μm from the lens member as a light emitting member, and an optical signal of 850 nm was incident on the lens member. The light propagation loss of the light emitted from the second optical path was 3.64 dB, and 4.21 dB when the optical fiber as the light emitting member was shifted by 20 μm with respect to the optical axis.

19,119 Tapered optical path 20,120 Optical member 21,121 Tapered optical waveguide 22,122 Core pattern 22A, 122A Core 22B, 122B Small diameter end (one end)
22C, 122C Large diameter end (other end)
25 Lens substrate 24, 124 Optical waveguide substrate 27, 127 Lens member 30, 130 Light emitting member 32 Optical fiber 35, 135 Optical waveguide 40, 140 Light incident member 116 Optical path conversion mirror

Claims (18)

  An optical member having a tapered optical path in which a cross-sectional area of the optical path increases from one end to the other end, and a lens member disposed on an optical axis extending from the other end side of the tapered optical path.   The optical member according to claim 1, wherein the tapered optical path is a core, and the core is surrounded by a clad having a refractive index lower than that of the core.   The optical member according to claim 1, wherein an optical path conversion mirror is disposed between the tapered optical path and the lens member on the optical axis.   The optical member according to claim 3, wherein a substrate is disposed between the lens member and the optical path conversion mirror.   The optical member according to claim 2, wherein the tapered optical path is formed by an optical waveguide having a core pattern composed of the plurality of cores.   The optical member according to any one of claims 1 to 5, wherein the optical path is tapered so that at least one of a width and a height increases toward the other end.   The optical member according to claim 1, wherein the lens member is a semi-convex lens having a convex surface on one surface.   The optical member according to claim 7, wherein a convex surface side of the semi-convex lens is disposed on the opposite side of the tapered optical path along the optical axis.   The optical member according to claim 1, wherein the lens member is a condensing lens system.   An optical member according to any one of claims 1 to 9, a light emitting member that emits a light beam toward the one end of the tapered optical path, and a light beam emitted from the other end of the tapered optical path. An optical device comprising a light incident member that is incident through the lens member.   The optical device according to claim 10, wherein the light emitting member is configured by a second optical path.   A light beam is incident on the one end of the tapered optical path from an end of the second optical path, and a cross-sectional area of one end of the tapered optical path is greater than or equal to a cross-sectional area of the end of the second optical path. Item 12. The optical device according to Item 11.   The optical device according to claim 10, wherein a cross-sectional area of the other end of the tapered optical path is smaller than a projected area of the lens member.   The optical member according to claim 1, a light emitting member that emits a light beam toward the other end side of the tapered optical path via the lens member, and one end of the tapered optical path An optical device comprising a light incident member on which a light beam emitted from the side is incident.   The optical device according to claim 14, wherein the light incident member is configured by a second optical path.   A light beam is incident on the end portion of the second optical path from the one end of the tapered optical path, and a cross-sectional area on one end side of the tapered optical path is equal to or smaller than a cross-sectional area of the end portion of the second optical path. The optical device according to claim 15.   The optical device according to claim 11 or 15, wherein the second optical path is formed of an optical fiber or an optical waveguide including a core and a clad having a refractive index lower than that of the core and surrounding the core.   The optical device according to claim 11 or 15, wherein a cross-sectional area of the second optical path is constant from one end to the other end.

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