JP4416115B2 - Method for manufacturing composite optical element - Google Patents

Description

  The present invention relates to a method for manufacturing a composite optical element, and more particularly to a manufacturing technique in a process of laminating a resin layer on an optical substrate.

  In general, a method for producing a composite optical element in which an ultraviolet curable resin layer is laminated on the surface of an optical substrate such as a glass lens is known. In particular, when manufacturing an optical component that requires an optical surface that is difficult to polish, such as an aspheric lens, the above manufacturing method easily forms an arbitrary optical surface by molding an ultraviolet curable resin. This is advantageous in comparison with polishing that requires man-hours and costs.

  The above-described method for manufacturing a composite optical element generally includes the following steps. First, an uncured ultraviolet curable resin is dropped onto the surface of the optical substrate (glass lens). Next, a mold is brought close to the surface of the optical substrate, and an ultraviolet curable resin is molded into a predetermined shape between the optical substrate and the mold. Further, the uncured ultraviolet curable resin molded into a predetermined shape is irradiated with ultraviolet rays from the side of the optical substrate to cure the ultraviolet curable resin. Finally, the mold is peeled from the cured ultraviolet curable resin (see, for example, Patent Document 1 below).

By the way, in the ultraviolet irradiation process in said manufacturing method, there exists a problem that a distortion generate | occur | produces in a resin layer because the cure rate of ultraviolet curable resin changes with places. Therefore, by arranging light modulation means such as optical filters, liquid crystal panels, transparent films with printed patterns, and optical scanning mechanisms on the irradiation path of ultraviolet rays, the uniformity of the curing rate of the ultraviolet curable resin is improved and distortion is generated. Techniques for preventing this have been proposed. (For example, refer to Patent Document 2 below).
JP-A-6-315943 JP-A-7-108623

However, in the above-described method for manufacturing a composite optical element, ultraviolet rays are irradiated onto the ultraviolet curable resin from the optical element side, so that the ultraviolet rays are refracted when passing through the optical element, thereby forming cured spots on the ultraviolet curable resin. Since “sinking” occurs in the resin layer in this portion, there is a problem that the surface (optical surface) of the resin layer cannot be formed with high accuracy.

For example, in the above-described method of arranging the light modulation means on the irradiation path of the ultraviolet light, the illuminance distribution of the ultraviolet light can be changed, but the illuminance unevenness caused by the refractive action of the optical substrate cannot be sufficiently eliminated. In addition, it is difficult to suppress a decrease in optical surface accuracy due to cured spots . In addition, this method has a problem that it is necessary to temporally control the mode of light modulation or to drive a complicated light scanning mechanism, which complicates the device structure and the control unit that controls the device structure. .

  Therefore, the present invention solves the above-mentioned problems, and the problem is that a composite optical element that can suppress the variation in the cured shape of the photo-curing resin by a simple method without performing complicated control. It is to provide a manufacturing method.

In view of such circumstances, the method of manufacturing a composite optical element of the present invention is a photocurable resin disposed on the surface of the optical base material when manufacturing a composite optical element formed by laminating a resin layer on an optical base material. In the manufacturing method of forming the resin layer by curing the photocurable resin by applying light irradiation to the photocurable resin, the mold is formed on the photocurable resin. The mold is continuously moved before passing through the contact position until reaching the final position where the molding of the photocurable resin by the mold is completed, and the mold comes into contact with the photocurable resin. start the light irradiation after time, the allowed to proceed curing process of the photocurable resin I line light irradiation in deformation process of the photocurable resin by the mold, the molding against the photocurable resin by the mold Characterized in that to complete the curing process of the photo-curing resin after the completion.

  According to the present invention, the light irradiation is performed while the photocurable resin is being deformed by the molding die, so that the influence on the shape of the resin layer due to the curing shrinkage (sink) by the light irradiation is caused by the deformation process of the photocurable resin. Since it becomes difficult to remain as a final shape, the shape accuracy of the resin layer can be increased.

In the present invention, certain that such a mold by the light irradiation is started after the time of contact with the photocurable resin, the curing process by light irradiation to inhibit molding process by the mold in progress The degree can be suppressed.

  In this case, it is desirable that the light irradiation be started after the time point when the outer diameter change amount of the photocurable resin by the mold becomes half of the total outer diameter change amount. According to this, since the curing process by light irradiation starts after about half of the molding process of the photocurable resin by the molding die is completed, the molding process can be performed more easily.

In the present invention, the more the this curing process of the photo-curing resin after the molding against the photocurable resin by the mold has been completed is completed, it is possible to reduce the molding inhibition by curing of the photocurable resin, molding Accuracy can be increased. This means that the curing process by light irradiation proceeds even after the completion of molding. Therefore, the light irradiation step in this case is usually performed in such a manner that light irradiation is further performed after the completion of molding.

  In the present invention, it is preferable that light irradiation is intermittently performed in the deformation process. According to this, by intermittently performing the light irradiation, the progress of the curing process can be suppressed, and the deformation factor due to the curing shrinkage can be efficiently removed during the period in which the light irradiation is suspended. Therefore, the shape accuracy of the resin layer can be further increased.

  According to the present invention, it is possible to produce an excellent effect that it is possible to suppress the occurrence of “sinking” in the resin layer in the composite optical element and to increase the optical surface accuracy.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram schematically illustrating a configuration of a manufacturing apparatus used in the method for manufacturing a composite optical element of the present embodiment, and FIGS. 2A to 2C are enlarged longitudinal sectional views of a receiving member 111. The manufacturing apparatus 100 of this embodiment is configured such that each unit is controlled by a control unit 101 configured by an MPU (microprocessor unit) or the like. The manufacturing apparatus 100 includes an optical base material holding unit 110, a resin supply unit 120, a molding processing unit 130, a light irradiation unit 140, an eccentricity measurement unit 150, a surface position measurement unit 160, and an optical axis adjustment unit 170. ing.

  The optical base material holding part 110 is provided with a receiving member (lens cradle) 111 that holds the optical base material 11 such as a lens, and a fixture 112 that fixes the optical base material 11 to the receiving member 111. The receiving member 111 may be made of, for example, iron, brass, stainless steel, or the like, and may have a surface plated with nickel. As shown in FIG. 2A, the receiving member 111 is formed integrally with a cylindrical portion 111a and a flange portion 111b that spreads from the lower end of the cylindrical portion 111a to the outer peripheral side. An optical opening 111op penetrating in the optical axis direction is formed inside the receiving member 111. In the case of the illustrated example, the opening cross section of the optical opening 111op is circular.

  Further, a stepped portion 111c having a shape opened to the inner peripheral side is formed at the upper end portion of the receiving member 111 (the upper opening edge of the cylindrical portion 111a). The step portion 111c is formed in an annular shape over the entire circumference. The stepped portion 111c is provided with a stepped bottom surface 111c1 that supports the optical base material 11 in the optical axis direction, and a stepped peripheral surface 111c2 configured to surround the optical base material 11 from the outer peripheral side. The inner diameter of the stepped portion 111c (the diameter of the inner edge of the stepped bottom surface 111c1) is (slightly) smaller than the outer peripheral diameter of the optical substrate 11, and the outer diameter of the stepped portion 111c (the diameter of the stepped peripheral surface 111c2) is the optical substrate 11. It is configured to be (slightly) larger than the outer periphery of the. In addition, the thickness of the stepped portion 111c (the width of the stepped peripheral surface 111c2 in the optical axis direction) is smaller than the thickness of the optical recording substrate 11 (for example, about half).

  The fixture 112 shown in FIG. 1 is configured in an annular shape, and has a flange surface that supports the peripheral edge of the optical base 11 in the direction of the optical axis and opposite to the direction supported by the step 111c of the receiving member 111. The flange surface is fixed to the receiving member 111 in a state where the flange surface is in contact with the peripheral edge portion of the optical substrate 11. Here, as a structure for fixing the fixing member 112 to the receiving member 111, a bayonet structure for engaging the receiving member 111 and the fixing member 112, or a screw structure for screwing the receiving member 111 and the fixing member 112 together. Appropriate fixing means such as can be used.

  With the above configuration, the optical base 11 is fitted (freely fitted) to the stepped portion 111c of the receiving member 111, the flange surface of the fixing tool 112 is brought into contact with the receiving member 111 from the opposite side, and the fixing tool 112 is received. By fixing to the member 111, the optical substrate 11 is held and fixed. The shapes of the receiving member 111 and the fixing tool 112 are arbitrary. For example, if the positional relationship between the receiving member 111 and the fixing tool 112 in the optical axis direction is reversed, what is called the fixing tool 112 is received. What becomes a member and is called a receiving member 111 is a fixture. That is, in the present invention, the holding component disposed on the light incident side of the optical base material 11 is referred to as a receiving member.

  The resin supply unit 120 is provided with a resin storage unit 121 and a supply nozzle 122 connected to the resin storage unit 121. An uncured photocurable resin (for example, an ultraviolet curable resin) is accommodated in the resin accommodating portion 121 and can be discharged from the supply nozzle 122 onto the optical substrate 11. The amount of the photocurable resin 12 discharged on the surface of the optical substrate 11 is set in advance. The amount of the photocurable resin 12 can be adjusted. The supply nozzle 122 is configured to be movable between a retracted position A and a supply position B shown in the figure.

  The molding processing unit 130 includes a mold drive mechanism 131 and a mold (mold) 132 that is moved by the mold drive mechanism 131. In the illustrated example, the mold driving mechanism 131 is configured such that the forming mold 132 can be moved in the optical axis direction (toward the optical substrate 11) by a ball screw mechanism in the illustrated example. The mold drive mechanism 131 can be configured by an arbitrary drive structure such as a fluid pressure cylinder mechanism as well as a screw mechanism.

  The light irradiation unit 140 is provided with a light irradiation device 141, and is configured to be able to irradiate light (for example, ultraviolet rays) from the light irradiation device 141 toward the optical substrate 11. In addition, a light diffusion plate 142 that diffuses the irradiation light of the light irradiation device 141 is provided. The light diffusing plate 142 is intended to make the irradiation light density of the light irradiation device 141 uniform, and can be constituted by, for example, a pearl coat (pearl coating) applied to the surface of a transparent glass plate. The light irradiation device 141 and the light diffusing plate 142 are configured to be movable between a retracted position A retracted from the optical axis of the optical base 11 and an irradiation position B disposed on the optical axis. ing.

  The eccentricity measuring unit 150 measures the eccentricity of the axial position of the transfer surface of the mold 132 and the optical axis position of the optical substrate 11. The eccentricity measurement unit 150 is provided with a measurement light irradiation / receiving device 151 that emits measurement light and measures the reflected light, and a monitor device 152 that displays the measurement result. The measurement light irradiation / receiving device 151 irradiates collimated light, for example, and measures the reflected light from the mold 132 and the optical substrate 11 of the collimated light. The monitor device 152 displays the axial center position of the mold 132 and the optical axis position of the optical substrate 11. On the monitor screen of the monitor device 152, for example, a target TG having a shape such as a cross indicating an axial center position or an optical axis position is displayed. Further, since the XY coordinate CD is also drawn on the monitor screen, the position coordinate of the target TG, that is, the position coordinate of the axis or the optical axis can be specified on the monitor screen.

  The surface position measurement unit 160 measures the surface position (height) of the optical base material 11, that is, the position of the surface of the optical base material 11 on the side facing the mold 132. The surface position measurement unit 160 is provided with a detector 161 and a measurement probe 162 connected to the detector 161. By bringing the measurement probe 162 into contact with the surface of the optical substrate 11, the surface probe The position can be measured. The measurement probe 162 is configured to be movable between a retracted position A retracted from the optical axis position and a measurement position B on the optical axis. The surface position measuring unit 160 can be constituted by a micrometer device, for example.

  An XY stage 171 is disposed in the optical axis adjustment unit 170. The XY stage 171 can adjust the planar position of the optical base material holding part 110 and has a structure in which the receiving member 111 is placed. With this optical axis adjustment unit 170, for example, the optical axis of the optical substrate 11 held and fixed on the optical substrate holding unit 110 can be made to coincide with the axis of the transfer surface of the mold 132. The XY stage 171 is provided with an optical opening that opens around the optical axis and allows the irradiation light irradiated by the light irradiation unit 140 to pass therethrough.

  Next, a more detailed structure of the receiving member 111 will be described with reference to FIG. As described above, the receiving member 111 is disposed on the light incident side (lower side in FIG. 1) of the light irradiated by the light irradiation unit 140 with respect to the optical base 11 and holds the optical base 11. And an optical opening 111op for allowing the irradiation light to pass therethrough. The inner surface 111p of the optical opening 111op is a cylindrical inner surface.

  In the example shown in FIG. 2A, a part of the inner surface 111p is a light reflecting surface 111p1 in a mirror surface (optical mirror surface) state, and the remaining part is a light scattering surface 111p2 in a rough surface state. In the case of the present embodiment, the light reflecting surface 111p1 is configured such that a part of the inner surface 111p becomes an optical mirror surface. The light reflecting surface 111p1 can be formed by ultraprecision cutting or polishing. The light reflecting surface 111p1 may be configured by forming a light reflecting layer made of aluminum or the like on the inner surface 111p. In this example, the light reflecting surface 111p1 is provided adjacent to the light incident side of the optical substrate 11. More specifically, the light reflecting surface 111p1 is a portion of the inner surface 111p that is closest to the optical substrate 11 (for example, about 1/3 of the length of the inner surface 111p from the optical substrate 11 side in the optical axis direction). It is formed only in the above part).

  In the example shown in FIG. 2B, the light reflecting surface 111p1 is provided at a position separated from the optical substrate 11 on the light incident side of the optical substrate 11. That is, a portion adjacent to the optical base 11 is provided with a light scattering surface 111p2, and a light reflecting surface 111p1 is formed further on the light incident side of the light scattering surface 111p2. In the illustrated example, the light reflecting surface 111p1 extends from the end opposite to the optical base 11 to a position having a space between the optical base 11 (from the end opposite to the optical base 11 to the inner surface 111p. To a position about 1/3 of the length in the optical axis direction).

  Further, in the example shown in FIG. 2C, the light reflecting surface 111p1 is formed over the entire inner surface 111p. That is, the entire inner surface 111p of the optical opening 111op of the receiving member 111 is a mirror-like light reflecting surface 111p1.

  In each of the above examples, the light reflecting surface 111p1 is formed in a range set evenly around the optical axis. That is, the light reflecting surface 111p1 is formed in an annular shape (cylindrical shape). However, the light reflecting surface 111p1 may be configured in a different manner in the circumferential direction when viewed around the optical axis. For example, the light reflecting surface 111p1 may be formed at a certain angular position around the optical axis, but may not be formed at another angular position.

  By the way, in general, the optical base material 11 refracts the irradiation light according to its photorefractive characteristics. Therefore, even if the incident intensity distribution of the irradiation light with respect to the optical base material 11 is uniform, after passing through the optical base material 12 The incident intensity distribution on the photo-curing resin 12 is not uniform. For example, if the optical substrate 11 is a concave lens, it has a light divergence characteristic, so that the photocuring speed tends to increase as it goes to the outer peripheral side of the photocurable resin 12.

  In the light reflection surface 111p1, when the light irradiation unit 140 irradiates the light curable resin 12 with light through the optical substrate 11, a part of the irradiation light is reflected as shown by a two-dot chain line in the figure, The reflected light enters the optical substrate 11. In this case, since the reflected light of the light reflecting surface 111p1 affects the incident intensity distribution of the irradiation light, the position and the formation range of the light reflecting surface 111p1 are appropriately set, so that the optical refraction action of the optical substrate 11 is improved. It is possible to reduce the uneven irradiation distribution.

  For example, in the example shown in FIG. 2A, the light reflecting surface 111p1 is disposed adjacent to the optical base material 11, so that the reflected light is relatively closer to the optical base material 11 than in the case shown in FIG. It becomes easy to enter the outer periphery. Further, in the example shown in FIG. 2B, the light reflecting surface 111p1 is provided at a position separated from the optical substrate 11, so that the reflected light is relatively optically compared to the case of FIG. It becomes easy to enter the inner peripheral part of the material 11. Further, in the example shown in FIG. 2C, since the light reflecting surface 111p is formed over the entire inner surface 111p of the receiving member 111, the incident light with respect to the optical base material 11 is determined by the length of the inner surface 111p in the optical axis direction. An intensity distribution is determined.

  On the other hand, in the light scattering surface 111p2, the light scattering angle is dispersed according to the rough surface state, and the upper limit is generated in the range of the light scattering angle depending on the rough surface state, so that the scattered light is incident on the optical substrate 11. However, it does not necessarily enter the photo-curing resin 12, and generally, the proportion not involved in the photo-curing process increases. Therefore, when the light reflecting surface 111p1 is not provided, it is difficult to control the incident light intensity distribution on the optical substrate 11 in a form that contributes to the photocuring process for the photocuring resin 12. Here, the remainder other than the light reflecting surface may be a light absorbing surface with little light reflection instead of a light scattering surface.

  Note that the position and range where the light reflecting surface 111p1 is formed vary depending on the inner diameter of the receiving member 111, the irradiation characteristics of the light irradiation device, the diffusion action of the light diffusion plate, the refraction characteristics of the optical substrate 11, and so on. Is determined in advance. Moreover, the light reflection surface 111p1 should just be a surface state which acts as an optical mirror surface with respect to the representative wavelength range which mainly contributes to the photocuring process of the photocurable resin 12 among irradiation light. However, when the light reflecting surface 111p1 is formed only on a part of the inner surface 111p of the receiving member 111, the light reflecting surface 111p1 is more positive than the rest of the inner surface 111p with respect to the light in the representative wavelength range. What is necessary is just to be comprised as an area | region with a high reflectance.

  Next, a method for manufacturing a composite optical element using the manufacturing apparatus 100 will be described with reference to FIGS. FIG. 5 is a schematic process diagram showing the steps of the manufacturing method. First, the axial position of the transfer surface of the mold 132 (position corresponding to the optical axis of the molded optical surface) is measured using the eccentricity measuring unit 150 (step 1). The measurement result is displayed as the target TG1 on the screen of the monitor device 152, and this display position is maintained. Since the resin supply unit 120, the light irradiation unit 140, and the surface position measurement unit 160 are retracted to the retreat position A, the axis of the transfer surface of the mold 132 can be measured through the optical opening 111op.

  Next, the optical base material 11 is supplied to the optical base material holding part 110 (step 2). Specifically, the optical substrate 11 is fitted into the receiving member 111 and fixed by the fixing tool 112. Usually, the optical substrate 11 is obtained by polishing an optical material such as glass, but is not limited to this, and may be a synthetic resin substrate formed by resin molding. The optical substrate 11 may be any optical component having optical transparency such as a lens, an optical filter, and a prism.

  Next, the optical axis position of the optical substrate 11 is measured using the eccentricity measuring unit 150 (step 3). Also at this time, the resin supply unit 120, the light irradiation unit 140, and the surface position measurement unit 160 are retracted to the retracted position A in the same manner as described above. When this measurement is performed, in the eccentricity measuring unit 150, the optical axis position of the optical base material 11 is indicated on the monitor screen of the monitor device 152 by the target TG2.

  Next, the optical axis position of the optical base material 11 measured as described above is adjusted using the optical axis adjustment unit 170 to coincide with the axial position of the transfer surface of the mold 132 (step 4). This adjustment is performed, for example, by adjusting the XY stage 171 so that the target TG2 displayed on the monitor screen of the monitor device 152 is aligned with the target TG2 that displays the axial center position of the transfer surface of the mold 132. This adjustment operation may be performed manually or may be configured to be performed automatically by the control unit 101. When step 4 is automatically performed, the measurement data is sent to the control unit 101 in steps 1 and 3 described above. In step 4, for example, the origin position of the XY coordinates CD displayed on the monitor screen may be configured to match the axis position of the transfer surface of the mold 132 measured in step 2.

  Next, the surface position on the mold 132 side of the optical substrate 11 is measured using the surface position measuring unit 160 (step 5). In this step 5, the measurement probe 162 is moved from the retracted position A to the measurement position B and brought into contact with the surface portion of the optical base material 11 at a predetermined plane position (for example, the optical axis position or the vertex position). Measurement is performed according to 151. After the measurement is completed, the surface position measurement unit 160 returns to the retracted position A and sends measurement data to the control unit 101.

  Next, the photocurable resin 12 is supplied onto the surface of the optical substrate 11 using the resin supply unit 120 (step 6). In Step 6, the supply nozzle 122 of the resin supply unit 120 is moved from the retracted position A to the supply position B, and the photocurable resin 12 is dropped from the optical base 11. This dropping amount is set in advance, so that the amount of the photo-curing resin can be precisely supplied onto the surface of the optical substrate 11. When the resin supply is completed, the supply nozzle 122 returns to the retracted position A. In addition, it is preferable to move the light irradiation unit 140 from the retracted position A to the irradiation position B after Step 6.

  Next, the shaping | molding die 132 is moved toward the optical base material 11 using the shaping | molding process part 130 (step 7). When the molding die 132 is moved, the molding die 132 is the closest to the optical substrate 11 according to the surface position data (data measured in step 5) of the optical substrate 11 sent to the control unit 101 in advance. The approaching position (hereinafter simply referred to as “final position”) is determined. This final position is a position separated from the surface of the optical substrate 11 by a distance corresponding to the thickness of the resin layer to be laminated on the optical substrate 11.

  In step 7, the mold 132 moves toward the optical substrate 11 and eventually comes into contact with the uncured photocurable resin 12. Hereinafter, the position of first contact with the photo-curing resin 12 is simply referred to as “contact position”. The mold 132 passes through the contact position and moves while deforming the photocurable resin 12, and eventually reaches the final position and stops. A resin layer formed by curing the photocurable resin 12 is molded by the molding die 132 at the final position.

  FIG. 3 is a graph showing the relationship between the moving speed of the mold 132 and its moving amount (or moving position). This embodiment is characterized in that the moving speed of the mold 132 is changed. Specifically, in step 7, as indicated by the solid line in the figure, the mold 132 is moved at a high speed until the mold 132 reaches the contact position, and the moving speed is increased immediately before reaching the contact position. The mold 132 is brought into contact with the photocurable resin 12 at a lower speed than before.

  In general, when the uncured photocurable resin 12 and the mold 132 come into contact with each other, the photocured resin 12 may be greatly shaken at the time of contact, which may cause bubbles to be mixed into the photocured resin 12. Further, since the uncured photo-curing resin 12 has a certain degree of viscosity, the photo-curing resin 12 is pushed and spread by the molding die 132 even after the molding die 132 contacts the photo-curing resin 12. When the moving speed of the mold 132 is high, air enters between the photocurable resin 12 and the mold 132 and bubbles are generated inside the photocurable resin 12. Further, when bubbles are generated inside the photocurable resin 12, if the moving speed of the mold 132 is high, there is no time margin for the bubbles to escape from the photocurable resin 12.

  On the other hand, by reducing the moving speed before the mold 132 contacts the photocurable resin 12 as described above, the photocurable resin 12 is shaken when the mold 132 contacts as described above. And air entrainment is reduced. In addition, since the moving speed of the mold 132 after contacting the photocurable resin 12 is small as described above, air is less involved in the photocurable resin 12 when the photocurable resin 12 is spread, Even if bubbles are generated inside the photo-curing resin 12, the moving speed of the molding die 132 is low, so that a sufficient time for the bubbles to escape from the photo-curing resin 12 during the movement of the molding die 132 can be secured. Further, when the mold 132 reaches the final position, there is an advantage that the positioning accuracy with respect to the final position is improved due to the low moving speed of the mold 132.

  On the other hand, the cycle time of the manufacturing process can be shortened and the manufacturing can be efficiently performed by moving the molding die 132 at a high speed before the contact position. Therefore, it is desirable that the initial moving speed of the mold 132 is as high as possible, and the moving speed of the mold 132 is as low as possible at the contact position and thereafter. The moving speed of the mold 132 before the contact position is basically better as it is faster, but it is preferably in the range of 1 to 10 cm / sec in order to reduce the load and vibration generation during deceleration, It is desirable to be about 5 cm / sec. Moreover, it is preferable that the moving speed of the shaping | molding die 132 after a contact position exists in the range of 0.01 mm / sec-0.2 mm / sec, and it exists in the range of 0.01-0.08 mm / sec especially. It is desirable.

  Here, it is preferable that the moving speed of the molding die 132 at the contact position is particularly low in order to reduce the shaking of the molding die 132 to the photo-curing resin 12. Therefore, for example, as indicated by a broken line in FIG. 3, the moving speed is temporarily lowered (for example, within the range of 0.01 to 0.05 mm / sec, particularly in the range of about 0.1 mm / sec before and after the time when the mold 132 passes the contact position). The movement speed increases after the mold 132 passes through the contact position (lower than the movement speed before the contact position, but higher than the movement speed at the contact position, for example, 0.04). More preferably, it is within a range of .about.0.08 mm / sec, particularly about 0.06 mm / sec).

  Further, when the surface of the optical substrate 11 has an aspherical shape or the like, and there is an inflection point on the surface, the photocurable resin 12 is in the process of being spread by the molding die 132. Since the curvature of the surface of the optical substrate 11 changes at the time when the outer edge passes through the inflection point, the risk of entraining air inside the photocurable resin 12 increases. Therefore, as shown by a two-dot chain line in the figure, when the outer edge position of the photocurable resin 12 passes through the inflection point in the process in which the photocurable resin 12 is spread by the mold 132, It is preferable that the moving speed is particularly low. Specifically, the moving speed of the mold 132 is further reduced before the outer edge of the photocurable resin 12 passes through the inflection point. At this time, the moving speed may be increased after passing the inflection point as in the illustrated example.

  In addition, as described later, when light irradiation is started before the mold 132 reaches the final position, if the viscosity of the light curable resin 12 is increased by the light irradiation curing process, air is easily entrained and the light curable resin The bubbles inside 12 are also difficult to escape. Therefore, as indicated by a three-dot chain line in the figure, it is preferable that the moving speed of the mold 132 is low after the start of curing of the photocurable resin 12. Specifically, the moving speed of the mold 132 is decreased at the same time as or before the start of light irradiation, or the moving speed of the mold 132 is gradually decreased with the passage of time after the light irradiation starts. Can be considered.

  The movement speed at the time when the mold 132 is at the contact position and the movement speed after passing through the contact position have different effects depending on conditions such as the viscosity of the photo-curing resin 12 and the shape of the transfer surface of the mold 132. Therefore, it is determined by conducting an experiment in advance. In addition, the contact position is different depending on the amount of the photo-curing resin 12 supplied, the initial shape of the photo-curing resin 12 due to the surface tension, and the like. It is preferable to determine by experiment or the like.

  By the way, in general, light irradiation by the light irradiation unit 140 is started after the mold 132 reaches the final position as described above and stops, but in this case, the molding by the mold 132 is completed. Since the photo-curing process is carried out, the shrinkage accompanying the photo-curing occurs, the resin layer is deformed and the molding accuracy is deteriorated, or a large strain remains inside the resin layer. The surface shape may change.

  Therefore, in the present embodiment, light irradiation by the light irradiation unit 140 is started before the mold 132 reaches the final position (step 8). FIG. 4 is a graph showing the relationship between the light irradiation density at the time of light irradiation by the light irradiation unit 140 and the movement amount (or movement position) of the mold 132. In this embodiment, the light irradiation is performed in parallel with the molding process of the mold 132. In particular, as shown by the solid line in the figure, it is preferable that the light irradiation is started after the time when the mold 132 reaches the contact position. Usually, light irradiation is started while passing through the contact position and spreading the photo-curing resin 12. By doing in this way, since a photocuring process can be produced, deforming the photocurable resin 12, the deformation | transformation of the resin layer by the cure shrinkage of the photocurable resin 12 and generation | occurrence | production of an internal distortion can be suppressed. That is, the photo-curing resin 12 itself undergoes curing shrinkage by the photo-curing process, but at this time, the photo-curing resin 12 is in a state of being spread by the molding die 132, and the force to spread the photo-curing resin 12 is exerted. Since the photo-curing resin 12 continues to be deformed due to the action, deformation and internal strain due to the curing shrinkage hardly remain.

  As shown by the solid line in the figure, the light irradiation start time is, for example, the time when the outer diameter change amount of the photocurable resin 12 is expanded by the mold 132 until it is about half of the total outer diameter change amount due to molding, or It can be after that. This is because when the light irradiation is started relatively early after the start of molding by the mold 132, the viscosity of the photocurable resin 12 increases due to photocuring, and it becomes difficult to mold with the mold 132 particularly in the latter half of the molding process. Because there is.

  Actually, if the curing process is completed before the mold 132 reaches the final position, the resin layer cannot be molded. Therefore, after the mold 132 reaches the final position, the photo-curing resin 12 is photocured. The mode of light irradiation is adjusted so that the process is completed. This light irradiation mode is determined by taking the light irradiation amount necessary for completing the curing of the photo-curing resin 12 and the balance between the reaction speed of the photo-curing process and the moving speed of the mold 132 into consideration. It is determined by setting the total amount of light irradiation until reaching the light irradiation amount or the light irradiation amount per unit time.

  For the same reason as described above, the average light irradiation density per unit time before the mold 132 reaches the final position, in particular, the relatively early average light irradiation density may be somewhat small. preferable. Therefore, for example, it is preferable to intermittently perform the light irradiation density when the molding die 132 is positioned between the contact position and the final position as indicated by a broken line in the figure. In this way, the influence of curing shrinkage can be eliminated mainly by the deformation action of the mold 132 during the period when the light irradiation is suspended, and the progress of the photocuring process can be suppressed. In addition, by configuring the light irradiation density to increase with time as shown in the two-dot chain line in the figure, it is possible to suppress the curing of the photo-curing resin at the initial stage of the molding process, so that the molding process can be performed without difficulty. Can do. In this case, it is more desirable to increase the light irradiation density of the irradiation step performed intermittently with time as shown in the figure.

  It should be noted that the start timing of light irradiation, that is, how much the light curable resin 12 is spread and spread, should be varied depending on various conditions such as the light irradiation density and the thickness of the light curable resin 12. Therefore, it is determined in advance by experiments or the like corresponding to these conditions. Here, as described above, in order to configure the photocuring process to be completed after the molding process by the mold 132 is completed, the light irradiation is completed after the mold 132 has reached the final position. It is preferable. In general, it is preferable that the light irradiation is completed 0.5 to 10 seconds after the mold 132 reaches the final position, and it is particularly preferable to terminate the light irradiation after 1 to 5 seconds. However, when the thickness of the molded shape of the photo-curing resin 12 is thin, or when the outer diameter of the optical base 11 is small and the amount of the photo-curing resin 12 is small, when the mold 132 reaches the final position. Alternatively, the light irradiation may be terminated immediately before the time point. Even in this case, the curing process of the photo-curing resin 12 is substantially completed after the mold 132 reaches the final position.

  As described above, when the mold 132 reaches the final position, the movement of the mold 132 is stopped (step 9), and then the curing process of the photocurable resin 12 is completed (step 10). Is moved away from the optical substrate 11 by moving (raising) in the opposite direction (step 11). Thereafter, the formed composite optical element is removed from the optical base material holding part 110 (step 12).

  In addition, the manufacturing method of the composite optical element of this invention is not limited only to the above-mentioned illustration example, Of course, various changes can be added within the range which does not deviate from the summary of this invention. For example, in the manufacturing method of the above embodiment, the configuration other than the step of supplying the photocurable resin 12 to the optical substrate 11, the step of molding the photocurable resin 12 with the mold 132, and the light irradiation step with respect to the photocurable resin 12. Can be implemented in a modified manner as appropriate, or can be omitted.

The schematic block diagram which shows typically the structure of embodiment of the manufacturing apparatus which concerns on this invention. The expanded sectional view (a)-(c) of the receiving member of the manufacturing apparatus. The graph which shows the relationship between the moving speed and movement amount (position) of the shaping | molding die in the manufacturing method which concerns on this invention. The graph which shows the relationship between the light irradiation density in the manufacturing method, and the movement amount (position) of a shaping | molding die. The schematic process drawing which shows the process of the manufacturing method.

DESCRIPTION OF SYMBOLS 100 ... Manufacturing apparatus, 101 ... Control part, 110 ... Optical base material holding part, 111 ... Receiving member, 112 ... Fixing tool, 120 ... Resin supply part, 130 ... Molding processing part, 132 ... Mold, 140 ... Light irradiation part , 141 ... light irradiation device, 142 ... light diffusing plate, 150 ... eccentricity measuring unit, 160 ... surface position measuring unit

Claims (3)

When manufacturing a composite optical element formed by laminating a resin layer on an optical substrate, the photocurable resin placed on the surface of the optical substrate is molded with a molding die, and the photocurable resin is formed on the photocurable resin. In the production method of forming the resin layer by curing the photocurable resin by applying light irradiation,
The molding die is continuously moved until it passes through the contact position before the molding die contacts the photocurable resin and reaches the final position where the molding with respect to the photocurable resin by the molding die is completed. start the light irradiation after the time the mold is in contact with the photocurable resin was allowed to proceed a curing process of the photocurable resin I line light irradiation in deformation process of the photocurable resin by the mold, the mold A method for producing a composite optical element , comprising: completing the curing process of the photo-curing resin after the molding of the photo-curing resin is completed .   2. The method of manufacturing a composite optical element according to claim 1, wherein the light irradiation is started after the time point when the outer diameter change amount of the photocurable resin by the molding die becomes half of the total outer diameter change amount. .   The method of manufacturing a composite optical element according to claim 1, wherein light irradiation is intermittently performed in the deformation process.

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