JP2006178139A - Method for manufacturing optical member, apparatus for manufacturing optical member, and electrooptical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an optical member capable of reducing a change in curvature of an optical member, an apparatus for manufacturing the optical member, and an electrooptical element. <P>SOLUTION: The apparatus 1 for manufacturing the optical member has a discharge head 15, a glass container 15 in which water 72 is reserved, and a UV irradiation machine 141. The discharge head 15 is provided with a liquid storage room 22, in which a liquid 21 composed of a UV curing resin having a hydrophobic property is contained. The water 72 is contained at the predetermined level in the glass container 13. First, droplets 71 are ejected to the water from the ejecting head 15. The droplets 71 in the water 72 are irradiated with UV rays 4 from an irradiation section 7 of the UV irradiation machine 141 to cure the droplets 71 in the water 72. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a manufacturing method of an optical member such as a lens used for optical communication, an optical member manufacturing apparatus, and an electro-optical element.

  One of optical members used for optical communication is a microlens. The microlens is formed, for example, on an emission surface of a surface emitting semiconductor laser (VCSEL: Vertical Cavity Surface Emitting Laser). The VCSEL increases the coupling efficiency of the light emitted from the VCSEL by forming a microlens on the exit surface of the VCSEL in order to align with an optical fiber or optical waveguide as an optical transmission medium with high accuracy. The connection with the outside is realized. Therefore, the shape of the microlens needs to be strictly controlled in order to obtain desired optical characteristics.

  In the microlens manufacturing method, for example, a liquid as a raw material of the microlens is ejected as droplets from the nozzle hole of the ejection head to the exit surface of the VCSEL. However, due to the weight of the liquid droplet, the liquid droplet adhering to the exit surface has been flattened. As a result, the microlens formed by curing the droplets could not obtain the required curvature.

  Therefore, for example, a method of obtaining a necessary shape by applying a hydrophilic treatment to the emission surface to be attached and performing a water repellency treatment on the periphery thereof so that the droplet does not spread beyond a desired region. Is known (for example, Patent Document 1). According to this method, the hydrophilic treatment is performed according to the size of the droplet, and the water-repellent treatment is performed on the region that is not desired to spread, so that the droplet can be prevented from spreading flat.

In addition, for example, a method of filling a droplet into a recess defined by a partition member is known (for example, Patent Document 2). According to this method, the partition member is configured to have low wettability, and since the droplet is repelled by the partition member, the surface of the droplet can be formed in a convex shape.
Accordingly, it is possible to prevent the droplets from spreading to the surroundings, and it is possible to suppress the droplets from becoming flat.

Japanese Patent Laid-Open No. 2000-2802 JP 2000-75106 A

  However, in the above-described conventional manufacturing method, it is possible to prevent the droplets from becoming flat and to increase the overall height, but since the self-weight is applied, the curvature change of the microlens formed by curing the droplets is large, There is a problem that it is difficult to obtain a microlens having a certain curvature. Due to the large change in curvature, the light emitted from the exit surface is likely to diffuse and the transmission efficiency is reduced.

  The present invention has been made paying attention to such an unsolved problem of the conventional technique, and an optical member manufacturing method and an optical member manufacturing apparatus capable of reducing the curvature change of the optical member. And an electro-optic element.

  In order to solve the above problem, a method for manufacturing an optical member according to the present invention includes a discharge step of discharging a hydrophobic first liquid, which is a raw material of the optical member, as a droplet from a discharge head, and the discharge step. The liquid droplets discharged by the liquid droplets into the second liquid having hydrophilicity stored in the container, and the liquid droplets charged into the second liquid by the liquid injection process are added to the liquid droplets. And an irradiation step of irradiating an energy ray for curing.

  According to this method, the first liquid having hydrophobicity is discharged from the discharge head by the discharge process, and the discharged liquid droplets are input to the second liquid having hydrophilicity stored in the container by the input process. Therefore, a droplet can be put in the second liquid. Accordingly, the liquid droplets in the second liquid are restrained from being flattened because a floating force is applied to the gravity. Furthermore, the droplet tends to be spherical due to the interfacial tension. And since an energy ray is irradiated by an irradiation process and this droplet is hardened, the optical member close | similar to a perfect sphere can be formed. As a result, it is possible to form an optical member with a small change in curvature, and the light transmission efficiency can be improved.

  In the method of manufacturing an optical member according to the present invention, it is preferable that the container has transparency, and the irradiation step irradiates the droplets introduced into the container from the outside of the container with the energy beam. .

  According to this method, since the container has transparency, it becomes possible to transmit energy rays from the outside of the container, and the droplets can be cured by the energy rays that have been transmitted through and irradiated. Furthermore, it is possible to irradiate energy rays from a position that does not interfere with the ejection head when ejecting droplets.

  In the method of manufacturing an optical member according to the present invention, it is preferable that the first liquid is an ultraviolet curable resin and the energy beam is an ultraviolet ray.

  According to this method, since the droplets made of the ultraviolet curable resin are cured by irradiating with ultraviolet rays, the optical member can be easily manufactured.

  In the method for producing an optical member according to the present invention, it is desirable that the first liquid is an ultraviolet curable resin having hydrophobicity, and the second liquid is transparent water or a transparent aqueous solution.

  According to this method, since droplets made of an ultraviolet curable resin having hydrophobicity are discharged to water or an aqueous solution, it is possible to make the droplets less compatible with each other and to make the droplets spherical by interfacial tension. Moreover, since it is transparent water or aqueous solution, it becomes possible to permeate | transmit ultraviolet rays, and even if it is a droplet in water or aqueous solution, an optical member can be formed by irradiation of ultraviolet rays.

  In the method for manufacturing an optical member according to the present invention, it is preferable that the irradiation step is cured before the droplet reaches the bottom of the container after landing on the second liquid stored in the container. .

  According to this method, since the droplet is cured before reaching the bottom after the droplet reaches the second liquid, the droplet does not become flat due to the force received when the droplet reaches the bottom. It can be cured in a spherical shape close to a sphere, and as a result, an optical member close to a true sphere can be formed.

  In order to solve the above-described problem, an optical member manufacturing apparatus according to the present invention discharges a first liquid having hydrophobicity, which is a raw material of an optical member, as droplets, and is discharged by the discharge head. Irradiation for irradiating energy droplets for curing the droplets onto a container storing a hydrophilic second liquid for containing the droplets and the droplets charged into the second liquid. Part.

  According to this configuration, the first liquid having hydrophobicity is discharged as droplets by the discharge head, and the droplets are put into the container in which the second liquid having hydrophilicity is stored. Drops can be placed in the inside. Accordingly, the liquid droplets in the second liquid are restrained from being flattened because a floating force is applied to the gravity. Furthermore, the droplet tends to be spherical due to the interfacial tension. And since an energy ray is irradiated from an irradiation part and this droplet is hardened, the optical member close | similar to a perfect sphere can be formed. As a result, it is possible to form an optical member with a small change in curvature, and the light transmission efficiency can be improved.

  In the optical member manufacturing apparatus according to the present invention, it is preferable that the container has transparency.

  According to this configuration, since the container is transparent, it is possible to transmit energy rays from the outside of the container, and the droplets can be cured by the energy rays that are transmitted through and irradiated. Furthermore, it is possible to irradiate energy rays from a position that does not interfere with the ejection head when ejecting droplets.

  In the optical member manufacturing apparatus according to the present invention, it is preferable that the first liquid is an ultraviolet curable resin and the energy beam is an ultraviolet ray.

  According to this configuration, the optical member can be easily manufactured because the droplets made of the ultraviolet curable resin are irradiated with ultraviolet rays to be cured.

  In the optical member manufacturing apparatus according to the present invention, it is desirable that the first liquid is an ultraviolet curable resin having hydrophobicity, and the second liquid is transparent water or a transparent aqueous solution.

  According to this configuration, since the droplet made of the ultraviolet curable resin having hydrophobicity is ejected to water or an aqueous solution, it is possible to make the droplets less compatible with each other and to make the droplet spherical by the interfacial tension. Moreover, since it is transparent water or aqueous solution, it becomes possible to permeate | transmit ultraviolet rays, and even if it is a droplet in water or aqueous solution, an optical member can be formed by irradiation of ultraviolet rays.

  In the optical member manufacturing apparatus according to the present invention, the irradiation unit irradiates the energy beam before the droplet reaches the bottom of the container after landing on the second liquid stored in the container. It is desirable to do.

  According to this configuration, since the droplet is cured before reaching the bottom after the droplet has landed on the second liquid, the droplet does not flatten due to the force received when reaching the bottom. It can be cured in a spherical shape close to a sphere, and as a result, an optical member close to a true sphere can be formed.

  In order to solve the above problems, in the electro-optical element according to the present invention, the optical member formed by the method of manufacturing an optical member is formed on a surface emitting semiconductor laser.

  According to this configuration, since the optical member close to the true sphere formed by curing in the second liquid is formed on the surface emitting semiconductor laser, the light emitted from the surface emitting semiconductor laser by the optical member Can be suppressed. Therefore, the light transmission efficiency can be improved.

  In order to solve the above problem, in the electro-optical element according to the present invention, an optical member manufactured using an optical member manufacturing apparatus is formed on a surface-emitting type semiconductor laser.

  According to this configuration, since the optical member close to the true sphere formed by curing in the second liquid is formed on the surface emitting semiconductor laser, the light emitted from the surface emitting semiconductor laser by the optical member Can be suppressed. Therefore, the light transmission efficiency can be improved.

  Embodiments of an optical member manufacturing method, an optical member manufacturing apparatus, and an electro-optical element according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view schematically showing the configuration of the optical member manufacturing apparatus of the present embodiment. Hereinafter, the configuration of a microlens manufacturing apparatus, which is an optical member manufacturing apparatus of the present embodiment, will be described with reference to FIG. As shown in FIG. 1, a microlens manufacturing apparatus 11 includes a droplet discharger 12 that discharges droplets, a glass container 13 as a container, and an ultraviolet irradiator 14 that irradiates ultraviolet rays as energy rays. Have.

  The droplet discharge machine 12 includes a discharge head 15, a slide mechanism (not shown) that slides the discharge head 15 in the X direction, a base 16 that supports the discharge head 15 and the slide mechanism, and a leg portion 17. Have.

  The discharge head 15 is used to discharge a liquid material (hereinafter referred to as “liquid”) 21 (see FIG. 2) as a first liquid that is a raw material of a microlens 53 (see FIG. 4) as an optical member. . The discharged droplet 71 (see FIG. 7) is made of, for example, an ultraviolet curable resin and is cured by being irradiated with ultraviolet rays. Moreover, the specific gravity of the droplet 71 is 1.2, which is slightly heavier than water, for example.

  The slide mechanism includes, for example, a slide shaft 18 and an X direction driving pulse motor 40 (see FIG. 3). The ejection head 15 can slide in the X direction along the slide shaft 18 in accordance with the rotation of the X direction driving pulse motor 40. The ejection head 15 is moved by the slide mechanism to determine the ejection position of the droplet 71 (see FIG. 7).

  An ejection head 15 and a slide mechanism are fixed to the base 16. A square through hole opening 19 is formed at a substantially central portion of the base 16.

  The leg portions 17 are respectively provided at the four corners on the back side of the base 16. The base 16 can be maintained at a predetermined height by the four legs 17.

  The glass container 13 is inserted into a space below the base 16 and is disposed below the opening 19 of the base 16. The glass container 13 is transparent and can transmit ultraviolet rays. Thereby, an ultraviolet-ray can be irradiated toward the inner side from the outer side of the glass container 13. FIG. The glass container 13 stores water 72 (see FIG. 7) as the second liquid. The water 72 may be an aqueous solution having transparency. The glass container 13 may be a transparent acrylic resin.

  The ultraviolet irradiator 14 is installed on one side of the glass container 13. On one side of the ultraviolet irradiator 14, an irradiation unit 73 (see FIG. 7) that irradiates the ultraviolet light 74 is provided. The ultraviolet irradiator 14 can irradiate the water 72 stored in the glass container 13 with ultraviolet rays 74.

  In the microlens manufacturing apparatus 11, the droplets 71 ejected from the ejection head 15 pass through the opening 19 and land on the water 72 of the glass container 13, and ultraviolet rays 74 are applied to the droplets 71 that sink in the water 72. , The droplet 71 is cured and a microlens 53 (see FIGS. 4 and 7) is formed.

  FIG. 2 is a schematic cross-sectional view showing the structure of the ejection head. Hereinafter, the structure of the ejection head of this embodiment will be described with reference to FIG. The discharge head 15 includes a liquid storage chamber 22 that stores the liquid 21 that is a raw material of the microlens 53, a nozzle 23 that discharges the liquid 21, a piezoelectric element 24, and a vibration plate 25.

  The microlens 53 (see FIG. 4) uses water 72 (see FIG. 7) stored in the glass container 13 as a liquid 71 that can be cured by applying energy rays such as light as droplets 71 (see FIG. 7). And droplets 71 descending in the water 72 are cured. The liquid 21 is an ultraviolet curable resin that cures when irradiated with ultraviolet rays as energy rays.

  The ultraviolet curable resin generally includes at least one of a prepolymer, an oligomer, and a monomer and a photopolymerization initiator. The ultraviolet curable resin of the present embodiment is a hydrophobic resin having a volatile component, and examples thereof include an ultraviolet curable acrylic resin, an epoxy resin, and a polyimide resin. Considering the wide selectivity of the viscosity, it is preferable to use an acrylic resin. Examples of the ultraviolet curable acrylic resin include acrylates such as epoxy acrylates and spiroacetal acrylates, methacrylates such as epoxy methacrylates, spiroacetal acrylates, polyester methacrylates, and polyether methacrylates. It is done.

  In general, many UV curable resins have high light transmittance. Therefore, even if the droplet 71 to be cured is irradiated with ultraviolet rays 74 from one side, the entire droplet 71 can be cured. Moreover, since there is little loss of light, it is particularly effective when forming the microlens 53 (see FIG. 4).

  The nozzle 23 is used to discharge the liquid 21 stored in the liquid storage chamber 22. The diameter of the nozzle 23 is, for example, 10 μm.

  The piezoelectric element 24 is, for example, a piezo element. The piezoelectric element 24 has a property of expanding and contracting when a voltage is applied using a piezoelectric effect (piezo effect).

  The vibration plate 25 is provided between the piezoelectric element 24 and the liquid storage chamber 22 and vibrates in conjunction with the expansion and contraction of the piezoelectric element 24. The diaphragm 25 is made of, for example, an elastic material such as silicon, and is configured to easily vibrate.

  From the above, by applying a voltage to the piezoelectric element 24 and applying a voltage change, the piezoelectric element 24 expands and contracts, and the pressure is transmitted to the diaphragm 25 in contact with the piezoelectric element 24. Then, the vibration plate 25 is elastically deformed so as to be concave toward the liquid storage chamber 22 side, and the supplied liquid 21 enters the concave space. Thereafter, when the application of voltage to the piezoelectric element 24 is stopped, the concave diaphragm 25 is returned to its original state, and the liquid 21 that has been supplied and entered applies pressure to the liquid storage chamber 22. As a result, the liquid 21 in the liquid storage chamber 22 is pushed, and a minute amount of the liquid 21 is pushed out from the nozzle 23. Further, the size of the droplet 71 can be controlled by adjusting the discharge amount of the droplet 71.

  FIG. 3 is a block diagram schematically showing the electrical configuration of the microlens manufacturing apparatus. Hereinafter, the configuration of the microlens manufacturing apparatus will be described with reference to FIG. The microlens manufacturing apparatus 11 includes a control circuit 31 for controlling the operation of the microlens manufacturing apparatus 11. The control circuit 31 stores a first interface (I / F) 33 that receives various data such as an ejection signal for ejecting the liquid 21 from the computer 32, a RAM 34, and a program and data for performing predetermined processing. A second interface (I / F) for receiving various data sent from a ROM 35, an oscillation circuit (not shown), a control unit 36 including a CPU, a drive waveform generation circuit 37, and a circuit in the microlens manufacturing apparatus 11. 38).

  The second interface 38 is connected to the driver 39, the ejection head 15, and the ultraviolet irradiator 14. The driver 39 is connected to the X direction driving pulse motor 40.

The RAM 34 is used for storing and reading various data. Discharge data transmitted from the computer 32 is stored in the RAM 34 via the first interface 33. Thereafter, the ejection data read from the RAM 34 is converted into various ejection signals and sent to the driver 39 to control the ejection head 15.
The drive waveform generation circuit 37 generates a pulse voltage that is a drive pulse for driving the piezoelectric element 24. By applying this pulse voltage to the piezoelectric element 24 and deforming the diaphragm 25, the liquid 21 can be discharged from the nozzle 23 or the liquid 21 can be separated from the nozzle 23.

  The X direction driving pulse motor 40 is connected to the second interface 38 via a driver 39. The driver 39 converts a signal including position data sent from the second interface 38 into a current. The X-direction driving pulse motor 40 rotates to move the ejection head 15 by a predetermined amount in the X direction according to this current.

  The ultraviolet irradiator 14 controls the irradiation (“ON” / “OFF”) of the ultraviolet light 74 by the irradiation signal for irradiating the ultraviolet light 74 from the computer 32. In addition, a voltage adjustment unit (not shown) may be provided between the control circuit 31 and the ultraviolet irradiator 14 to adjust the intensity of the ultraviolet light 74. Further, the ultraviolet irradiator 14 may irradiate the ultraviolet ray 74 toward the glass container 13 as an independent ultraviolet irradiator 14 without being connected to the control circuit 31.

  FIG. 4 is a cross-sectional view schematically showing the structure of the electro-optic element. The electro-optical element 51 in this embodiment is obtained by forming a microlens 53 that is an optical member on a light emitting / receiving element. As a light emitting element which is one of the light receiving and emitting elements, for example, a semiconductor laser, a semiconductor light emitting diode, an organic EL device, and the like are included. As a light receiving element that is one of the light receiving and emitting elements, for example, a solid-state imaging device, a photodiode, an MSM (Metal Semiconductor Metal) photo director, and the like are included. Hereinafter, the configuration of an electro-optic element in which a microlens 53 is formed on a surface emitting semiconductor laser (VCSEL) 52, which is one of semiconductor lasers, will be described with reference to FIG.

  The electro-optic element 51 includes a surface emitting semiconductor laser (VCSEL) 52 and a microlens 53. As shown in FIG. 4, the surface emitting semiconductor laser 52 includes a first substrate 54, a vertical resonator (hereinafter referred to as “resonator”) 55 formed on the first substrate 54, and a resonator 55. The first electrode 56 is formed, and the second electrode 57 is formed on the lower surface side of the first substrate 54. The first substrate 54 is, for example, an n-type GaAs (gallium arsenide) substrate.

  The resonator 55 includes a distributed reflection type multilayer mirror layer (hereinafter referred to as “first mirror layer”) 58, an active layer 61 formed on the first mirror layer 58, and an oxidation formed on the active layer 61. A current confinement layer 62 made of aluminum and a distributed reflection type multilayer mirror layer (hereinafter referred to as “second mirror layer”) 63 are provided.

  The columnar portion 59 (columnar deposit) includes a part of the first mirror layer 58, the active layer 61, and the second mirror layer 63. An insulating layer 60 is formed around the columnar portion 59.

  The first electrode 56 and the second electrode 57 are provided to inject current into the resonator 55. Specifically, a current is injected into the active layer 61 by the first electrode 56 and the second electrode 57. The first electrode 56 can be formed, for example, from a laminated film of an alloy of Au and Zn and Au. The first electrode 56 has an opening 64 in a part of the upper surface of the columnar part 59. Of the upper surface of the columnar portion 59, a portion opened by the opening 64 is an emission surface 65. The shape of the opening 64 of the first electrode 56 is, for example, circular when viewed from above. The second electrode 57 is made of, for example, a laminated film of an alloy of Au and Ge and Au.

  The surface emitting semiconductor laser 52 configured as described above can emit light (laser) in a direction perpendicular to the first substrate 54 from an emission surface 65 provided on the upper surface of the resonator 55.

The microlens 53 is disposed on the emission surface 65 of the surface emitting semiconductor laser 52. The microlens 53 is guided on the edge 64 a of the circular opening 64 formed in the first electrode 56 and is disposed on the emission surface 65. Since the microlens 53 is close to a true sphere, light (laser) can be emitted efficiently.
Further, the microlens 53 and the surface emitting semiconductor laser 52 are fixed to each other by applying and curing an adhesive 68 made of an ultraviolet curable resin on the emission surface 65. The ultraviolet curable resin that is the raw material of the adhesive 68 and the ultraviolet curable resin that is the raw material of the microlens 53 are different in refractive index.

  Next, a general operation of the surface emitting semiconductor laser 52 will be described. The following driving method of the surface emitting semiconductor laser 52 is an example, and various modifications can be made without departing from the gist of the present invention.

  First, when a voltage is applied between the first electrode 56 and the second electrode 57, recombination of electrons and holes occurs in the active layer 61, and light emission occurs. Stimulated emission occurs when the generated light reciprocates between the second mirror layer 63 and the first mirror layer 58, and the light intensity is amplified. When the optical gain exceeds the optical loss, laser oscillation occurs and enters the microlens 53 from the emission surface 65 on the top surface of the columnar portion 59. After the emission angle is adjusted by the microlens 53, light (laser) is emitted in a direction perpendicular to the first substrate 54 (upper side shown in FIG. 4).

  5 and 6 are schematic cross-sectional views showing the manufacturing process of the surface emitting semiconductor laser. Hereinafter, a method of manufacturing the surface emitting semiconductor laser will be described with reference to FIGS.

  First, in step 1 shown in FIG. 5, the semiconductor multilayer film 66 is formed on the surface of the first substrate 54 by epitaxial growth while modulating the composition. The semiconductor multilayer film 66 is formed by stacking the first mirror layer 58, the active layer 61, and the second mirror layer 63 on the first substrate 54 in this order. Next, a resist layer 67 having a predetermined pattern is formed. The resist layer 67 is formed in a predetermined pattern by applying a photoresist (not shown) on the semiconductor multilayer film 66 and then patterning the photoresist by a photolithography method.

  In step 2, the columnar portion 59 is formed. First, using the resist layer 67 formed in step 1 as a mask, a part of the second mirror layer 63, the active layer 61, and the first mirror layer 58 is etched by, for example, a dry etching method to form a columnar semiconductor deposited body ( Columnar part) 59 is formed. As a result, the resonator 55 including the columnar portion 59 is formed on the first substrate 54. Thereafter, the resist layer 67 is removed.

  In step 3, the current confinement layer 62 is formed as necessary. The current confinement layer 62 is formed by oxidizing a part of the second mirror layer 63. In the surface-emitting type semiconductor laser 52 (see FIG. 4) provided with the current confinement layer 62, current flows only in a portion where the current confinement layer 62 is not formed (non-oxidized portion). Therefore, in the step of forming the current confinement layer 62 by oxidation, the current density can be controlled by controlling the range of the current confinement layer 62 to be formed.

In step 4 shown in FIG. 6, an insulating layer 60 surrounding the columnar portion 59 is formed. Here, as a material for forming the insulating layer 60, for example, a polyimide resin is used. First, for example, a resin precursor (polyimide precursor) is applied onto the resonator 55 by using a spin coating method to form a resin precursor layer (not shown). At this time, the resin precursor layer is formed so that the film thickness is larger than the height of the columnar portion 59.
Next, the substrate is heated, for example, to remove the solvent, and then the upper surface 59a of the columnar portion 59 is exposed. As a method for exposing the upper surface 59a of the columnar portion 59, a CMP method, a dry etching method, a wet etching method, or the like can be used. Thereafter, the insulating layer 60 is formed by imidizing the resin precursor layer.

In step 5, a first electrode 56 and a second electrode 57 for injecting current into the active layer 61, and a laser beam emission surface 65 are formed. First, a laminated film (not shown) of, for example, an alloy of Au and Zn and Au is formed on the insulating layer 60 and the upper surface 59a of the columnar portion 59 (see Step 4 in FIG. 6), for example, by vacuum deposition. In this case, an Au layer is formed on the outermost surface. Next, a portion where the laminated film is not formed is formed on the upper surface 59a of the columnar portion 59 by a lift-off method. This portion becomes the opening 64. As described above, the opening 64 has a circular shape when the first electrode 56 is viewed from above in order to determine the position of the microlens 53. That is, the opening 64 of the first electrode 56 is used as a bank. A region in the opening 64 in the upper surface 59 a of the columnar portion 59 functions as the emission surface 65.
Next, a laminated film of, for example, an alloy of Au and Ge and Au is formed on the back surface 54a of the first substrate 54 by, for example, a vacuum deposition method.

Next, the microlens 53 is fixed on the emission surface 65 with an adhesive material (see FIG. 4). The adhesive material is, for example, an ultraviolet curable resin, and is an epoxy resin or an acrylic resin. However, an ultraviolet curable resin having a different refractive index is used as the ultraviolet curable resin used when forming the microlens 53. This ultraviolet curable resin is applied onto the emission surface 65. Next, by rolling a plurality of microlenses on top of the surface-emitting type semiconductor laser 52 (first electrode 56), one of the microlenses is guided to the edge 64a of the circular opening 64, and the emission surface 65 is reached. On top. Next, ultraviolet rays are irradiated to cure the adhesive (ultraviolet curable resin) 68 and to fix the microlens 53 and the surface emitting semiconductor laser 52 together.
The electro-optic element 51 having the surface emitting semiconductor laser 52 and the microlens 53 is formed by the above steps (Step 1 to Step 5) (see FIG. 4).

  FIG. 7 is a schematic cross-sectional view showing a forming process for forming a microlens by the microlens manufacturing apparatus. Hereinafter, a manufacturing method for manufacturing a microlens by the microlens manufacturing apparatus will be described with reference to FIG.

  As shown in FIG. 7, the microlens manufacturing apparatus 11 includes an ejection head 15, a glass container 13 in which water 72 is stored, and an ultraviolet irradiator 14.

As described above, the liquid storage chamber 22 is provided in the ejection head 15, and the liquid 21 made of an ultraviolet curable resin having hydrophobicity is stored in the liquid storage chamber 22.
Water 72 is stored in the glass container 13 to a predetermined height.

  The ultraviolet irradiator 14 has an irradiation unit 73 that irradiates the ultraviolet ray 74 on one side surface thereof, and can irradiate the ultraviolet ray 74 in a direction perpendicular to the surface. By arranging the ultraviolet irradiator 14 on the side of the glass container 13, the ultraviolet light 74 is irradiated toward the glass container 13. Since the glass container 13 is formed transparently, the ultraviolet rays 74 can pass through the water 72 stored in the glass container 13. The ultraviolet curable resin is cured by receiving irradiation of ultraviolet rays 74 from the irradiation unit 73 for a short time.

Next, a method for manufacturing a microlens using the microlens manufacturing apparatus will be described.
First, in the first step (discharge step), the droplet 71 is discharged from the discharge head 15 toward the water 72 stored in the glass container 13. The droplets 71 are ejected at certain intervals by the ejection head 15. The size of the droplet 71 is, for example, 10 μm to 30 μm.

  In the second step (injection step), the droplet 71 reaches the water 72 and starts to sink. As the droplet 71 enters the water 72, volatile components contained in the droplet 71 form a film of the droplet 71. Further, since the droplet 71 is in the water 72, it is suppressed from being flattened by adding buoyancy to gravity, and close to a true sphere due to the interfacial tension.

In the third step (irradiation step), the droplets 71 are irradiated with ultraviolet rays 74. The ultraviolet irradiator 14 irradiates the ultraviolet rays 74 to the droplet 71 that sinks after the droplet 71 enters the water 72 and becomes spherical. The ultraviolet ray 74 irradiates an area where the droplet 71 can be cured before landing on the water 72 and reaching the bottom 13a of the glass container 13 by an irradiation signal from the computer. For example, the speed of settling in the water 72 is determined from the specific gravity of the droplet 71. For example, since the droplet 71 is cured by being irradiated with ultraviolet rays for 2 to 3 seconds, a height (range) necessary for curing is required.
The droplets 71 irradiated with the ultraviolet rays 74 are cured to become microlenses. This microlens is formed in a true spherical shape because the droplet 71 close to the true sphere is cured. As a result, a plurality of microlenses 53 formed in a spherical shape are accumulated in the bottom 13 a of the glass container 13.

  By placing the hydrophobic droplets 71 in the water 72 by the above method, the water does not mix with each other, and the specific gravity is slightly heavier than that of the water 72, so that it is hardly affected by gravity. It becomes possible to do so. Further, the droplet 71 becomes close to a true sphere due to the interfacial tension, and the droplet 71 is irradiated with the ultraviolet ray 74, so that the microlens 53 close to the true sphere can be formed.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) According to the present embodiment, the discharge head 15 discharges the hydrophobic UV curable resin as the droplet 71 and puts the droplet 71 into the water 72 stored in the glass container 13. It is possible to suppress the amount by which the droplet 71 is flattened by gravity by buoyancy. Moreover, since it tends to be spherical due to the interfacial tension, the droplet 71 can be made close to a true sphere. Therefore, since the irradiation unit 73 irradiates the ultraviolet rays 74 to the droplets 71 close to the true sphere in the water 72, the true spherical microlens 53 can be formed. As a result, the microlens 53 having a small change in curvature can be formed.

  (2) According to this embodiment, since the glass container 13 and the water 72 are transparent to the ultraviolet ray 74, the ultraviolet ray 74 can be transmitted, and the droplets 71 in the water 72 are irradiated with the ultraviolet ray 74. Can do. Therefore, the droplet 71 can be cured in the water 72, and the microlens 53 can be formed.

  (3) According to the present embodiment, since the spherical microlens 53 manufactured by curing in the water 72 is provided on the emission surface 65 of the surface emitting semiconductor laser 52, the surface emitting semiconductor laser 52 It becomes possible to suppress the diffusion of the emitted light by the microlens 53. Therefore, since it is close to a true sphere (because the curvature change is small), the transmission efficiency can be improved.

  (4) According to the present embodiment, the microlens 53 can be easily manufactured because it is discharged into the water 72 and cured. For example, it is easier than forming a microlens while rolling, or forming a microlens by fitting it into a mold.

In addition, this embodiment is not limited above, It can also implement with the following forms.
(Modification 1) In the above embodiment, the droplet 71 is formed by the droplet discharge method using the droplet discharger 12. Alternatively, droplets may be formed by a dispenser method using a dispenser. According to this, the viscosity of the liquid can be increased as compared with the droplet discharge method, and a relatively large microlens can be formed.

  (Modification 2) In the above embodiment, the microlens 53 is formed by discharging the hydrophobic droplet 71 to the hydrophilic water 72. Alternatively, the microlens 53 may be formed by discharging a hydrophilic droplet to a hydrophobic liquid. According to this, a droplet can be made close to a true sphere without intermingling with each other. As a result, a true spherical microlens can be produced.

  (Modification 3) In the said embodiment, the irradiation part 73 of the ultraviolet irradiation machine 14 was fixed, and it was orient | assigned only to one direction of the glass container 13. FIG. This may be irradiated by following a droplet 71 that sinks in the water 72 by providing a rotation mechanism that allows the irradiation unit to rotate up and down. According to this, the range which irradiates the ultraviolet-ray 74 from the irradiation part 73 can be narrowed, and an ultraviolet-ray can be irradiated efficiently.

  (Modification 4) In the said embodiment, the ultraviolet curable resin used for the liquid 21 used what has a volatile component. This is not limited to a volatile component, and a water-repellent component or a plasticizer may be added.

(Modification 5) In the said embodiment, the glass container 13 had transparency as a whole. Alternatively, a glass container that is not transparent may be used. In this case, for example, the ultraviolet light 74 is irradiated from the opening side (upper side) of the glass container toward the water 72 stored therein. Thereby, it becomes possible to irradiate the droplets 71 in the water 72 with the ultraviolet rays 74, and the microlens 53 can be made.
Moreover, you may make it make only the part which the ultraviolet-ray 74 permeate | transmits in the glass container 13 transparent.

  (Modification 6) In the above embodiment, the ultraviolet rays 74 are transmitted through the transparent glass container 13 after being irradiated onto the droplets 71. Alternatively, a mirror may be provided on one side surface inside the glass container 13 (on the side opposite to the irradiation direction of the ultraviolet light 74) so that the irradiated ultraviolet light 74 is reflected in the glass container 13. According to this, since the droplet 71 is irradiated not only with the ultraviolet ray 74 irradiated from the irradiation unit 73 but also with the reflected ultraviolet ray, the amount of the ultraviolet ray 74 irradiated from the irradiation unit 73 can be suppressed.

The perspective view which shows typically the structure of the manufacturing apparatus of the optical member in one Embodiment. FIG. 3 is a cross-sectional view schematically showing the structure of the ejection head. The block diagram which shows typically the electric constitution of a microlens manufacturing apparatus. Sectional drawing which shows the structure of a surface emitting semiconductor laser and a micro lens typically. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of a surface emitting semiconductor laser. FIG. 6 is a schematic cross-sectional view showing a manufacturing process of a surface emitting semiconductor laser. The schematic cross section which shows the manufacturing method which manufactures a microlens in order.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Micro lens manufacturing apparatus as an optical member manufacturing apparatus, 12 ... Droplet discharge machine, 13 ... Glass container as a container, 13a ... Bottom part, 14 ... Ultraviolet irradiation machine, 15 ... Discharge head, 16 ... Base, 17 DESCRIPTION OF SYMBOLS ... Leg part, 18 ... Slide shaft, 19 ... Opening part, 21 ... Liquid as 1st liquid, 22 ... Liquid storage chamber, 23 ... Nozzle, 24 ... Piezoelectric element, 25 ... Diaphragm, 31 ... Control circuit, 32 ... Computer, 33 ... First interface, 34 ... RAM, 35 ... ROM, 36 ... Control unit, 37 ... Drive waveform generation circuit, 38 ... Second interface, 39 ... Driver, 40 ... Pulse motor for X direction drive, 51 ... Electro-optical element, 52... Surface emitting semiconductor laser (VCSEL), 53... Micro lens as optical member, 64 .. Opening, 65... Ejecting surface, 68. ... water as the second liquid, 73 ... irradiation unit, 74 ... ultraviolet ray as the energy ray.

Claims (12)

A discharge step of discharging the hydrophobic first liquid, which is a raw material of the optical member, as a droplet from the discharge head;
A charging step of charging the liquid droplets discharged in the discharging step into a hydrophilic second liquid stored in a container;
An irradiation step of irradiating the liquid droplets introduced into the second liquid by the injection step with an energy beam for curing the liquid droplets;
The manufacturing method of the optical member characterized by having. It is a manufacturing method of the optical member according to claim 1,
The container has transparency;
The said irradiation process irradiates the said energy beam to the said droplet with which the said container was thrown into the said container from the outer side of the said container, The manufacturing method of the optical member characterized by the above-mentioned. It is a manufacturing method of the optical member according to claim 1 or 2,
The first liquid is an ultraviolet curable resin,
The method of manufacturing an optical member, wherein the energy ray is ultraviolet light. It is a manufacturing method of the optical member according to any one of claims 1 to 3,
The first liquid is an ultraviolet curable resin having hydrophobicity,
The method for producing an optical member, wherein the second liquid is transparent water or a transparent aqueous solution. It is a manufacturing method of the optical member according to any one of claims 1 to 4,
The method of manufacturing an optical member, wherein the irradiating step hardens the liquid droplets before reaching the bottom of the container after landing on the second liquid stored in the container. An ejection head that ejects a hydrophobic first liquid as a raw material of the optical member as droplets;
A container storing a second liquid having hydrophilicity for containing the droplets discharged by the discharge head;
An irradiating unit that irradiates the droplets charged into the second liquid with energy rays for curing the droplets;
An apparatus for manufacturing an optical member, comprising: It is a manufacturing apparatus of the optical member according to claim 6,
The said container has transparency, The manufacturing apparatus of the optical member characterized by the above-mentioned. It is a manufacturing apparatus of the optical member according to claim 6 or 7,
The first liquid is an ultraviolet curable resin,
The said energy beam is an ultraviolet-ray, The manufacturing apparatus of the optical member characterized by the above-mentioned. It is a manufacturing apparatus of the optical member as described in any one of Claims 6-8,
The first liquid is an ultraviolet curable resin having hydrophobicity,
The apparatus for producing an optical member, wherein the second liquid is transparent water or a transparent aqueous solution. An optical member manufacturing apparatus according to any one of claims 6 to 9,
The said irradiation part irradiates an energy beam before reaching the bottom part of the said container after the said droplet reaches | attains the said 2nd liquid stored in the said container, The manufacturing apparatus of the optical member characterized by the above-mentioned .   6. An electro-optical element, wherein an optical member formed by the method for manufacturing an optical member according to claim 1 is formed on a surface-emitting type semiconductor laser. 11. An electro-optical element, wherein an optical member manufactured using the optical member manufacturing apparatus according to claim 6 is formed on a surface emitting semiconductor laser.

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