JP2021026073A - Optical device and manufacturing method of optical device - Google Patents

Abstract

To appropriately inhibit adhesive resin protruding from a bottom side of a downsized optical element from interfering with the incident area and emission area of an optical element.SOLUTION: As shown in FIG. 1, an optical device 1 comprises: a substrate 10; a semiconductor laser chip 50 fixed on the substrate 10; and a collimator lens 20 including a bottom face 23 that is fixed via adhesive resin 40 to the substrate 10, a first principal surface 21 receiving incident light from the semiconductor laser chip 50, and a second principal surface 22 emitting emission light generated based on the incident light entering the first principal surface 21. A liquid repellent film 30 is applied on the collimator lens 20 so as to cover an incident area 21a of the first principal surface 21 for at least receiving the incident light and an emission area 22a of the second principal surface 22 for at least emitting the emission light. The liquid repellent film 30 has liquid repellency for the adhesive resin 40 which is not yet cured.SELECTED DRAWING: Figure 1

Description

The present invention relates to an optical device and a method for manufacturing the optical device.

Patent Document 1 describes an optical device in which light emitted from a semiconductor laser light source is converted into collimated light by a collimating lens. In such an optical device, for example, a semiconductor laser chip is provided on a substrate via a submount, and a collimating lens is fixed at a predetermined position using an adhesive resin.

JP-A-5-181091

Here, in the above-mentioned optical device, by reducing the size of the collimating lens (optical element), for example, the distance from the bottom surface of the lens to the incident region where the light of the lens is incident and the exit region where the light is emitted. When becomes smaller, the adhesive resin that crawls up from the bottom surface side of the lens may interfere with the incident region and the emitted region of the lens.

As a measure to prevent the adhesive resin from interfering with the incident region and the exit region of the lens, it is conceivable to use an adhesive resin having a high viscosity or thixotropy of the adhesive. Since such an adhesive resin does not easily get wet and spread, the above-mentioned creeping up is unlikely to occur. However, it is difficult to apply an adhesive resin having a high viscosity or thixotropy of the adhesive thinly at the stage of applying the adhesive resin on the substrate. Therefore, when such an adhesive resin is used, the minimum value of the distance from the bottom surface of the lens to the incident region and the exit region of the lens is limited to the minimum coatable thickness of the adhesive resin. That is, the method of using an adhesive resin having a high viscosity or thixotropic property of the adhesive should be used when the distance from the bottom surface of the lens to the incident region or the exit region of the lens is extremely small (for example, when it is 0.3 mm or less). I can't. As described above, conventionally, for example, when the distance from the bottom surface of the lens (optical element) to the incident region or the exit region of the lens is extremely small, the adhesive resin that crawls up from the bottom surface side of the lens is the incident region or the exit region of the lens. It is not possible to properly suppress the interference with the lens.

The present invention has been made in view of the above circumstances, and an object of the present invention is to appropriately prevent an adhesive resin creeping up from the bottom surface side of a miniaturized optical element from interfering with an incident region or an emitted region of the optical element. And.

The optical device according to one aspect of the present invention has a substrate, a light source fixed on the substrate, and a bottom surface, the bottom surface is fixed to the substrate via an adhesive resin, and incident light from the light source is incident. An optical element having an incident surface and an emitting surface that emits emitted light generated based on the incident light incident on the incident surface is provided, and the optical element covers at least an incident region in which the incident light is incident on the incident surface. A liquid-repellent film is applied so as to cover and at least cover the light-emitting region on the light-emitting surface, and the liquid-repellent film has liquid-repellent properties against the adhesive resin in the state before curing.

The method for manufacturing an optical device according to one aspect of the present invention is a substrate, an incident surface on which incident light from a light source is incident, and an emitted surface that emits emitted light generated based on the incident light incident on the incident surface. This is a method for manufacturing an optical device including an optical element having an optical element, wherein the light source is fixed to a substrate, the incident surface covers at least the incident region where the incident light is incident, and at least the emitted light is emitted. An optical element having a liquid-repellent film having a liquid-repellent property against the adhesive resin in the state before curing is formed so as to cover the exit region of the optical element so that the bottom surface of the optical element and the substrate face each other. The second step of holding the adhesive resin in a predetermined position on the substrate and the third step of dropping the adhesive resin in the uncured state between the optical element and the substrate and filling the adhesive resin between the substrate and the optical element. And a fourth step of curing the adhesive resin.

According to the present invention, it is possible to appropriately prevent the adhesive resin that crawls up from the bottom surface side of the miniaturized optical element from interfering with the incident region and the emitted region of the optical element.

FIG. 1 is a schematic view of an optical device according to the present embodiment. FIG. 2 is a front view and a rear view of the collimating lens. FIG. 3 is a diagram showing variations of the liquid repellent film forming portion. FIG. 4 is a diagram illustrating a method of manufacturing the optical device of FIG. FIG. 5 is a diagram illustrating a method of manufacturing an optical device according to a comparative example.

[Explanation of Embodiments of the Present Invention]
First, the contents of the embodiments of the present invention will be listed and described. The optical device according to the embodiment has a substrate, a light source fixed on the substrate, and a bottom surface, the bottom surface is fixed to the substrate via an adhesive resin, and an incident surface on which incident light from the light source is incident. , And an optical element having an exit surface that emits the emitted light generated based on the incident light incident on the incident surface, and the optical element covers at least the incident region where the incident light is incident on the incident surface. A liquid-repellent film is applied on the exit surface so as to cover at least the emission region where the emitted light is emitted, and the liquid-repellent film has liquid repellency against the adhesive resin in the state before curing.

In such an optical device, a liquid-repellent film having a liquid-repellent property against the adhesive resin in the state before curing is formed so as to cover the incident region and the emitted region in the optical element. By forming the liquid-repellent film in this way, the adhesive resin fixing the optical element to the substrate is applied from the bottom surface side of the optical element to the incident surface forming the incident region and the exit surface forming the exit region. It is possible to suppress crawling up. As a result, it is possible to appropriately prevent the adhesive resin from interfering with the incident region and the emitted region of the optical element. Then, in such an optical device, it is possible to prevent the adhesive resin from interfering with the incident region and the exit region regardless of the viscosity or thixotropic property of the adhesive resin. Therefore, there is no limitation on the distance from the bottom surface of the optical element to the incident region or the exit region according to the minimum coatable thickness of the adhesive resin, which is a problem when an adhesive resin having high viscosity or thixotropy is used. Therefore, even for a miniaturized optical element, it is possible to appropriately suppress the adhesive resin from interfering with the incident region and the emitted region. Further, for example, when an adhesive resin having high viscosity or chicosis is used in order to prevent the adhesive resin from interfering with the incident region or the exit region, the position of the optical element is adjusted while immersing the optical element in the adhesive resin. When doing so, the force required to adjust the position of the optical element increases. If the force required to adjust the position of the optical element increases, slippage tends to occur between the optical element (lens, etc.) and the collet, and proper alignment may not be possible. In this respect, in the optical device according to the present embodiment, it is possible to suppress the adhesive resin from interfering with the incident region and the exit region regardless of the viscosity or thixotropic property of the adhesive resin, so that the adhesive resin having high viscosity or thixotropic property can be used. The alignment of the optical element can be easily performed as compared with the case where it is used. When an adhesive resin having high viscosity or thixotropy is used, the difficulty of alignment becomes particularly remarkable when the distance between the substrate and the bottom surface of the optical element is short. Therefore, for example, it is conceivable to improve the ease of alignment by increasing the distance between the substrate and the bottom surface of the optical element. However, when the distance between the substrate and the bottom surface of the optical element becomes large, the amount of displacement when the optical element is fixed increases due to the shrinkage of the adhesive resin during curing, and the temperature changes even after the fixing. If there is, there is a possibility that the amount of misalignment of the optical element will increase due to thermal expansion. In this respect as well, in the optical device according to the present embodiment, which does not need to use an adhesive resin having high viscosity or thixotropy in the first place, it is necessary to increase the distance between the substrate and the bottom surface of the optical element from the viewpoint of easy alignment. Therefore, it is possible to avoid a large amount of misalignment of the optical element.

The liquid-repellent film may have a wetting angle of 65 ° or more with respect to n-hexadecane. As a result, the adhesive resin can be appropriately repelled by the liquid-repellent film, and the adhesive resin can be appropriately crawled up from the bottom surface side of the optical element to the incident surface constituting the incident region and the exit surface forming the exit region. It can be suppressed.

The optical element may have an exposed portion on the bottom surface side of the incident surface to which a liquid repellent film is not applied. An adhesive resin crawls up from the bottom surface side of such an exposed portion to form a fillet. As a result, the optical element can be more strongly fixed to the substrate.

A plurality of exposed portions may be provided intermittently. As a result, a plurality of the above-mentioned fillets are formed, and the optical element can be more strongly fixed to the substrate.

The method for manufacturing an optical device according to an embodiment includes a substrate, an incident surface on which incident light from a light source is incident, and an emitted surface that emits emitted light generated based on the incident light incident on the incident surface. A method of manufacturing an optical device including an optical element, wherein the light source is fixed to a substrate, the incident surface covers at least the incident region where the incident light is incident, and at least the emitted light is emitted on the exit surface. An optical element having a liquid-repellent film having a liquid-repellent property against the adhesive resin in the state before curing is formed on the substrate so as to cover the ejection region so that the bottom surface of the optical element and the substrate face each other. The second step of holding the adhesive resin in a predetermined position, and the third step of dropping the adhesive resin in the state before curing between the optical element and the substrate and filling the adhesive resin between the substrate and the optical element. It comprises a fourth step of curing the adhesive resin.

According to such a manufacturing method, when the adhesive resin is dropped in the third step, the liquid-repellent film formed on the incident surface and the exit surface repels the adhesive resin, and the incident surface and the exit region constituting the incident region are formed. It is suppressed that the adhesive resin crawls up on the exit surface constituting the above. As a result, it is possible to appropriately prevent the adhesive resin from interfering with the incident region and the emitted region of the optical element.

[Details of Embodiments of the present invention]
Specific examples of the optical device according to the embodiment of the present invention will be described below with reference to the drawings. It should be noted that the present invention is not limited to these examples, and is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims. In the following description, the same elements will be designated by the same reference numerals in the description of the drawings, and duplicate description will be omitted.

FIG. 1 is a schematic view of an optical device 1 according to the present embodiment. The optical device 1 is an optical module incorporating a collimating lens 20 which is a minute optical element. As shown in FIG. 1, the optical device 1 includes a substrate 10, a collimating lens 20 (optical element), a liquid repellent film 30, an adhesive resin 40, and a semiconductor laser (LD: Laser Diode) chip 50 (light source). And a submount 60. In the following, the optical device 1 will be described with reference to FIG. 2 in addition to FIG. FIG. 2 is a front view (FIG. 2 (a)) and a rear view (FIG. 2 (b)) of the collimating lens 20.

The substrate 10 is a substrate on which each configuration such as the collimating lens 20 described above is mounted. The substrate 10 faces the bottom surface 23 of the collimating lens 20 on its mounting surface, and the adhesive resin 40 in the state before curing is dropped between the substrate 10 and the collimating lens 20, and the adhesive resin 40 is cured. The collimating lens 20 is mounted (fixed) on the mounting surface. The substrate 10 has a submount 60 mounted on the mounting surface thereof.

The collimating lens 20 is a lens that converts the light emitted from the semiconductor laser chip 50 into collimated light (makes it parallel light). That is, the collimating lens 20 emits emitted light which is collimated light generated based on the incident light from the semiconductor laser chip 50. The collimating lens 20 has a first main surface 21 (incident surface) and a second main surface 22 (emission surface) facing each other in the direction in which the collimating light travels. The first main surface 21 has a lens surface 21x that receives light from the semiconductor laser chip 50. In the first main surface 21, the surfaces other than the lens surface 21x are substantially flat, whereas the lens surface 21x is, for example, a spherical surface. The shape of the lens surface 21x is not limited to a spherical surface, and may be an aspherical lens surface. The lens surface 21x is a substantially circular region when viewed from the direction in which the collimated light travels. The first main surface 21 has an incident region 21a in which the synchrotron radiation L1 from the semiconductor laser chip 50 is incident on the first main surface 21. The collimated light L2 that has passed through the lens surface 21x is collimated and travels in the direction of the second main surface 22. The second main surface 22 emits the collimated light L2 as the emitted light L3. The second main surface 22 has an emission region 22a that emits the emission light L3.

The collimating lens 20 is fixed (fixed) to the substrate 10 by the adhesive resin 40 with the bottom surface 23 facing the mounting surface of the substrate 10. The height of the collimating lens 20 (the length in the direction intersecting the mounting surface of the substrate 10) can be, for example, about 0.5 mm. The length of the collimating lens 20 in the direction in which the collimating light travels (the maximum length from the first main surface 21 to the second main surface 22) can be, for example, about 0.5 mm.

The liquid-repellent film 30 is a film formed so as to cover at least the incident region 21a and the exit region 22a and has liquid repellency with respect to the adhesive resin 40 in the state before curing. The liquid-repellent film 30 includes a liquid-repellent film 31 that at least covers the incident region 21a and a liquid-repellent film 32 that at least covers the exit region 22a. The liquid-repellent film 30 may be any liquid-repellent film as long as it has liquid-repellent properties with respect to the adhesive resin 40 in the state before curing. The liquid-repellent film 30 is, for example, a film having liquid-repellent properties against a UV-curable adhesive resin in a state before curing. The liquid repellent film 30 is, for example, a liquid repellent film having a wetting angle of 65 ° or more with respect to n-hexadecane. Further, as the liquid repellent film 30, a resin thin film containing fluorine having a thickness of 20 nm or less (for example, a thin film containing a perfluoroalkyl group) may be used. Since such a liquid-repellent film 30 has a thin thickness, it is possible to reduce the influence on the optical characteristics when using visible / near-infrared light. The liquid-repellent film 31 and the liquid-repellent film 32 may cover at least the incident region 21a and the exit region 22a. Further, in consideration of the variation of the element and the variation in the manufacturing, the region may be provided in a region wider than the incident region 21a and the emission region 22a. For example, the liquid-repellent film 31 may be provided in a part of the lens surface 21x including the incident region 21a, or may be provided in the entire region of the lens surface 21x. Further, the liquid repellent film 31 may be provided on a part of the outer region of the lens surface 21x on the first main surface 21 or the entire first main surface.

FIG. 3 is a diagram showing variations in the formed portion of the liquid repellent film 31. The location where the liquid repellent film 31 is formed may be any of those shown in FIGS. 3 (a) to 3 (e), or may be other than those shown in FIGS. 3 (a) to 3 (e). Each of the views shown in FIGS. 3A to 3E is a view of the first main surface 21 viewed from the direction in which light is incident on the collimating lens 20. In the example shown in FIG. 3A, the liquid repellent film 31 is formed on the entire first main surface 21 including the lens surface 21x. Further, in the example shown in FIG. 3B, the collimating lens 20 has an exposed portion 25 to which the liquid repellent film 31 is not applied in the portion of the first main surface 21 on the bottom surface 23 side. That is, in the example shown in FIG. 3B, the liquid repellent film 31 is formed in the region of the first main surface 21 excluding the exposed portion 25. In the configuration in which the liquid repellent film 31 is not applied to a part of the first main surface 21 (exposed portion 25 near the bottom surface 23), the adhesive resin 40 is a part of the first main surface 21 (exposed). Since it crawls up to the portion 25) and forms a so-called fillet, the substrate 10 and the substrate 10 are compared with the configuration in which the liquid repellent film 31 is formed on the entire first main surface 21 as shown in FIG. 3A. The adhesion to the collimating lens 20 can be further strengthened.

Further, for example, as shown in FIGS. 3 (c) and 3 (d), it is conceivable to adopt an array lens in which a plurality of collimating lenses 20 are integrated. In the array lens as well, for example, as shown in FIG. 3C, the liquid repellent film 31 may be formed except for the exposed portion 25 near the bottom surface 23. Further, for example, as shown in FIG. 3D, in the array lens, each collimating lens 20 is provided so that the lower end of the lens surface 21x of the collimating lens 20 and the lower end of the bottom surface of the collimating lens 20 are in contact with each other. It is conceivable to set the distance from the lower end of the lens surface 21x of the collimating lens 20 to the bottom surface 23 to zero, and to provide each collimating lens 20 so that the lens surfaces 21x of the adjacent collimating lenses 20 are in contact with each other. In this case, since the lens surface 21x is circular, a plurality of exposed portions 25 are intermittently (encave-like) provided in a portion of the first main surface 21 near the bottom surface 23. Further, for example, as shown in FIG. 3E, a liquid repellent film 31 may be provided on a part of the lens surface 21x so as to cover at least the incident region 21a. The region to which the liquid-repellent film 31 is applied is made wider than the incident region 21a in consideration of variations in the elements and variations in manufacturing. In the example shown in FIG. 3E, since the exposed portion 25 is provided on the first main surface 21 near the bottom surface 23, the adhesion between the substrate 10 and the collimating lens 20 can be further strengthened. it can. Further, the area to which the liquid-repellent film 31 is applied can be narrowed as compared with the case where the liquid-repellent film 31 is applied to the entire first main surface 21 and the lens surface 21x.

Returning to FIG. 1, the adhesive resin 40 is a resin that fixes the collimating lens 20 at a predetermined position on the substrate 10. The adhesive resin 40 is introduced so as to penetrate between the collimating lens 20 and the substrate 10. The adhesive resin 40 is, for example, a resin that is cured by UV irradiation or heat, and is, for example, an epoxy-based resin or a modified acrylic-based resin. As the adhesive resin 40, one having a relatively low viscosity and thixotropy is used, and for example, one having a viscosity of about 400 cP is used.

The semiconductor laser chip 50 is a light source that emits laser light. The semiconductor laser chip 50 is fixed on the substrate 10 via a submount 60.

Next, a method of manufacturing the optical device 1 will be described with reference to FIG. First, the semiconductor laser chip 50 is fixed to the substrate 10 via the submount 60 (first step).

Then, as shown in FIG. 4A, the collimating lens 20 repels at least the incident region 21a on which the incident light from the semiconductor laser chip 50 on the first main surface 21 (incident surface) is incident. A liquid film 31 is formed. Further, the collimating lens 20 is formed with a liquid repellent film 32 so as to at least cover an emission region 22a that emits emission light generated based on the incident light on the second main surface 22. The liquid-repellent film 30 (liquid-repellent film 31, liquid-repellent film 32) has liquid-repellent properties with respect to the adhesive resin 40 in the state before curing. The collimating lens 20 on which the liquid-repellent film 30 is formed is held at a predetermined position on the substrate 10 so that the bottom surface 23 thereof and the substrate 10 face each other (second step). The position for holding the collimating lens 20 is adjusted to a position where collimation can be appropriately performed in consideration of the light emitting point of the semiconductor laser chip 50.

Subsequently, as shown in FIG. 4B, the uncured adhesive resin 40 is dropped between the collimating lens 20 and the substrate 10, and the adhesive resin 40 is filled between the substrate 10 and the collimating lens 20 (No. 1). Step 3). In this case, since the liquid repellent film 30 is formed at least in the incident region 21a and the exit region 22a of the collimating lens 20, the adhesive resin 40 is suppressed from crawling up (crawling up from the bottom surface 23 side). Finally, the adhesive resin 40 is cured to fix the position of the collimating lens 20 on the substrate 10 (fourth step). Curing of the adhesive resin 40 may be carried out by UV irradiation or by heating.

Next, the operation and effect of the optical device 1 and the manufacturing method of the optical device 1 according to the present embodiment will be described with reference to the optical device 101 according to the comparative example shown in FIG.

FIG. 5 is a diagram illustrating a method of manufacturing the optical device 101 according to a comparative example. The optical device 101 shown in FIG. 5B has the same configuration as the optical device 1 according to the present embodiment, except that the liquid repellent film 30 is not formed. That is, in the manufacturing process, first, as shown in FIG. 5A, the semiconductor laser chip 50 is fixed to the substrate 10 via the submount 60, and then the adhesive resin 40 is applied onto the substrate 10. Then, as shown in FIG. 5B, the collimating lens 20 is held so as to be immersed in the applied adhesive resin 40. After that, the position of the collimating lens 20 is adjusted to a position where it can be appropriately collimated with respect to the light emitting point of the semiconductor laser chip 50. Then, the position of the collimating lens 20 is fixed on the substrate 10 by curing the adhesive resin 40 by UV irradiation or the like.

Here, in the optical device 101, when the collimating lens 20 is miniaturized, for example, the distance from the bottom surface of the collimating lens 20 to the incident region and the exit region of the lens is reduced (for example, as small as about 1 mm). , The adhesive resin 40 that crawls up from the bottom surface side of the collimating lens 20 may interfere with the incident region and the exit region of the collimating lens 20 (see FIG. 5B).

On the other hand, as shown in FIG. 1, the optical device 1 according to the present embodiment has a substrate 10, a semiconductor laser chip 50 fixed on the substrate 10, and a bottom surface 23, and the bottom surface 23 is adhered to the substrate 10. It is fixed to the substrate 10 via the resin 40, and is generated based on the incident light incident on the first main surface 21 and the first main surface 21 on which the incident light from the semiconductor laser chip 50 is incident. A collimating lens 20 having a second main surface 22 that emits emitted light is provided, and the collimating lens 20 covers at least the incident region 21a on which the incident light is incident on the first main surface 21 and the second main surface 21. A liquid-repellent film 30 is applied on the surface 22 so as to cover at least the emission region 22a that emits emitted light, and the liquid-repellent film 30 has liquid repellency with respect to the adhesive resin 40 in the state before curing.

In such an optical device 1, a liquid-repellent film 30 having a liquid-repellent property with respect to the adhesive resin 40 in the state before curing is formed so as to cover at least the incident region 21a and the exit region 22a of the collimating lens 20. .. By forming the liquid-repellent film 30 in this way, the adhesive resin 40 fixing the collimating lens 20 to the substrate 10 forms the incident region 21a from the bottom surface 23 side of the collimating lens 20. Crawling up to the second main surface 22 constituting the surface 21 and the emission region 22a can be suppressed. As a result, it is possible to appropriately prevent the adhesive resin 40 from interfering with the incident region 21a and the exit region 22a of the collimating lens 20.

Here, as a measure for suppressing the adhesive resin 40 from interfering with the incident region 21a and the exit region 22a of the collimating lens 20 (correspondence different from the present embodiment), the adhesive is adhered with increased viscosity or tixo property. It is conceivable to use a resin. For example, since the adhesive resin having a clay of about 20000 cP does not easily get wet and spread, it is difficult for the adhesive resin to crawl up in the incident region 21a and the exit region 22a as described above. However, in the configuration using an adhesive resin having high viscosity or thixotropic property, there are the following problems.

First, it is difficult to apply an adhesive resin having a high viscosity or thixotropy of the adhesive thinly at the stage of applying the adhesive resin on the substrate. Therefore, when such an adhesive resin is used, the minimum value of the distance from the bottom surface of the point diagram to the incident region and the exit region of the lens is limited to the minimum coatable thickness of the adhesive resin. That is, the method of using an adhesive resin having a high viscosity or thixotropic property of the adhesive should be used when the distance from the bottom surface of the lens to the incident region and the exit region of the lens is extremely small (for example, when it is 0.3 mm or less). Cannot be done (first problem).

Secondly, when the position of the lens is adjusted while immersing the lens in the adhesive resin after applying the adhesive resin having high viscosity or thixotropy of the adhesive, the force required for adjusting the position of the lens becomes large. When making minute lens adjustments, it is common to hold the lens with a vacuum collet, but if the force required to adjust the lens position increases, slippage will easily occur between the lens and collet, and an appropriate adjustment will be made. There is a risk that you will not be able to do it (second problem). Such a phenomenon is particularly likely to occur when the distance between the substrate and the bottom surface of the lens is short.

Thirdly, when the distance between the substrate and the bottom surface of the lens is increased in order to avoid the second problem described above, the amount of lens misalignment during fixing becomes large due to shrinkage during curing of the adhesive resin. In addition, even if there is a temperature change after fixing, the amount of lens misalignment due to thermal expansion becomes large (third problem).

On the other hand, in the optical device 1 according to the present embodiment, it is possible to suppress the adhesive resin 40 from interfering with the incident region 21a and the exit region 22a regardless of the viscosity or the thixo property of the adhesive resin 40. Alternatively, it is possible to suppress the occurrence of the above-mentioned first to third problems, which is a problem when an adhesive resin having high viscosity is used. That is, since the optical device 1 does not use an adhesive resin having high viscosity or chicosis, the collimating lens 20 according to the minimum coatable thickness of the adhesive resin, which is a problem when an adhesive resin having high viscosity or the like is used. Since there is no limitation on the distance from the bottom surface 23 of the lens to the incident region 21a and the exit region 22a, it is possible to appropriately suppress the adhesive resin 40 from interfering with the incident region 21a and the exit region 22a even in the miniaturized collimating lens 20. .. Further, in the optical device 1, since it is possible to suppress the adhesive resin 40 from interfering with the incident region 21a and the exit region 22a regardless of the viscosity or the chic property of the adhesive resin 40, the adhesive resin having a high viscosity or chic property is used. The collimating lens 20 can be easily aligned as compared with the case where it is used. Further, in the optical device 1 according to the present embodiment, which does not require the use of an adhesive resin having high viscosity or thixotropy, it is necessary to increase the distance between the substrate 10 and the bottom surface 23 of the collimating lens 20 from the viewpoint of ease of alignment. Therefore, it is possible to avoid a large amount of misalignment of the collimating lens 20.

The liquid repellent film 30 described above may have a wetting angle of 65 ° or more with respect to n-hexadecane. As a result, the adhesive resin 40 can be appropriately repelled by the liquid-repellent film 30, and the adhesive resin 40 is appropriately prevented from creeping up from the bottom surface 23 side of the collimating lens 20 to the incident region 21a and the exit region 22a. Can be done.

It should be noted that n-hexadecane is a linear hydrocarbon and is an oil having a typical molecular structure as a non-polar molecule, and is a typical sample of an oil having a small surface tension (good wettability). is there. The adhesive resin 40 is a resin that assumes that minute optical components are attached to a substrate. Therefore, the base material of the adhesive resin 40 considered as the target is specifically an epoxy-based or modified acrylic-based material. Since the adhesive resin 40 is non-polar and a relatively low-molecular-weight organic material that can flow in a liquid state is a substantial target, the liquid-repellent film 30 has a wetting angle of 65 ° or more with respect to n-hexadecane. It is considered that the adhesive resin 40 in the state before curing has liquid repellency. The wet angle is "the angle between the liquid surface and the solid surface where the free surface of the static liquid touches the solid wall (takes the angle inside the liquid)" (Physical and Chemical Dictionary (Iwanami Shoten No. 4). The wettability test method is specified in, for example, the Japanese industry standard (JIS (Japanese Industrial Solids)) for the wettability test method for the surface of the substrate glass: JIS R 3257. The liquid repellent film 30 A thin film containing a perfluoroalkyl group is used as a perfluoroalkyl group. The perfluoroalkyl group is described as CF3 (CF2) n−, and all hydrogen atoms in the alkyl chain are replaced with fluorine atoms. When a film containing the above is used as a liquid-repellent film, a functional group containing fluorine is present on the surface of the film. Therefore, the affinity is poor regardless of whether it is polar or non-polar, and it has liquid-repellent performance. As described above, the liquid-repellent film 30 containing the perfluoroalkyl group has a liquid-repellent film 30 with respect to the adhesive resin 40 in the state before curing. Has liquid repellency.

The collimated lens 20 described above may have an exposed portion 25 (see FIG. 3B) to which the liquid repellent film 30 is not applied at a portion of the first main surface 21 on the bottom surface 23 side. In such an exposed portion 25, the adhesive resin 40 crawls up from the bottom surface 23 side to form a fillet. As a result, the collimating lens 20 can be more firmly fixed to the substrate 10.

As shown in FIG. 3D, a plurality of exposed portions 25 may be provided intermittently. As a result, a plurality of the above-mentioned fillets are formed, and the collimating lens 20 can be more strongly fixed to the substrate 10.

The method for manufacturing the optical device 1 according to the present embodiment is based on the incident light incident on the substrate 10, the first main surface 21 on which the incident light from the semiconductor laser chip 50 is incident, and the first main surface 21. A method for manufacturing an optical device including a collimating lens 20 having a second main surface 22 that emits the emitted light generated by the above, the first step of fixing the semiconductor laser chip 50 to the substrate 10, and the first step. With respect to the adhesive resin 40 in the state before curing so as to cover at least the incident region 21a on which the incident light is incident on the main surface 21 of 1 and at least the emission region 22a on which the emitted light is emitted on the second main surface 22. A second step of holding the collimating lens 20 on which the liquid-repellent film 30 having the liquid-repellent property is formed at a predetermined position on the substrate 10 so that the bottom surface 23 of the collimating lens 20 and the substrate 10 face each other. A third step of dropping the adhesive resin 40 in the uncured state between the collimating lens 20 and the substrate 10 (see FIG. 4A) and filling the adhesive resin 40 between the substrate 10 and the collimating lens 20. (See FIG. 4 (b)) and a fourth step of curing the adhesive resin 40.

According to such a manufacturing method, when the adhesive resin 40 is dropped in the third step, the liquid repellent film 30 formed so as to cover at least the first main surface 21 and the second main surface 22 adheres. The resin 40 is repelled, and the adhesive resin 40 is suppressed from creeping up in the incident region 21a and the exit region 22a. As a result, it is possible to appropriately prevent the adhesive resin 40 from interfering with the incident region 21a and the exit region 22a of the collimating lens 20. Further, in such a manufacturing method, since there is no adhesive resin 40 when the lens position is adjusted (when the optical element is held), the lens position can be easily adjusted, and the incident region 21a and the incident region 21a and The collimating lens 20 can be appropriately fixed to the substrate 10 with the thin adhesive resin 40 without causing the adhesive resin 40 to interfere with the emission region 22a.

Although the present embodiment has been described above, the present invention is not limited to the above embodiment. For example, the collimating lens 20 has been described as an example of the optical element, but the optical element may be another lens, or an optical element other than a lens such as a microreflector or a microprism, an optical isolator, a polarizing plate, and a wave plate. It may be an element. For example, in the case of a microreflector, since the emitted light reflected based on the incident light is generated, the reflecting surface becomes the incident surface and the emitting surface. Therefore, the region where the incident light on the reflecting surface is incident, reflected and emitted is the incident region and the exit region. Further, in the case of an optical isolator, the incident light incident on one end face is emitted from the other end face, whereas the incident light incident on the other end face is not emitted from one end face. The other end face is the entrance surface and the other end face is the exit surface.

1 ... Optical device, 10 ... Substrate, 20 ... Collimating lens (optical element), 21 ... First main surface (incident surface), 21x ... Lens surface, 22 ... Second main surface (emission surface), 23 ... Bottom surface , 25 ... exposed part, 30, 31, 32 ... liquid repellent film, 40 ... adhesive resin, 50 ... semiconductor laser chip (light source), 60 ... submount.

Claims (5)

With the board
With the light source fixed on the substrate,
It has a bottom surface, the bottom surface is fixed to the substrate via an adhesive resin, and is generated based on an incident surface on which incident light from the light source is incident and the incident light incident on the incident surface. An optical element having an exit surface that emits emitted light,
With
The optical element is coated with a liquid repellent film so as to cover at least the incident region where the incident light is incident on the incident surface and at least cover the emitted region where the emitted light is emitted on the emitting surface.
The liquid-repellent film is an optical device having liquid-repellent properties against the adhesive resin in a state before curing. The optical device according to claim 1, wherein the liquid-repellent film has a wetting angle of 65 ° or more with respect to n-hexadecane. The optical device according to claim 1 or 2, wherein the optical element has an exposed portion on the bottom surface side of the incident surface to which the liquid repellent film is not applied. The optical device according to claim 3, wherein a plurality of exposed portions are provided intermittently. Manufacture of an optical device including a substrate, an incident surface on which incident light from a light source is incident, and an optical element having an emitted surface that emits emitted light generated based on the incident light incident on the incident surface. The way,
The first step of fixing the light source to the substrate and
It has liquid repellency to the adhesive resin in the state before curing so as to cover at least the incident region where the incident light is incident on the incident surface and at least cover the emitted region where the emitted light is emitted on the emitting surface. A second step of holding the optical element on which the liquid-repellent film is formed at a predetermined position on the substrate so that the bottom surface of the optical element and the substrate face each other.
A third step of dropping the adhesive resin in a state before curing between the optical element and the substrate and filling the adhesive resin between the substrate and the optical element.
A method for manufacturing an optical device, comprising a fourth step of curing the adhesive resin.