JP2019130790A - Mold apparatus, injection molding apparatus, injection molding method, resin lens, resin lens manufacturing method, lens unit, and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding apparatus, an injection molding method and a resin lens capable of aligning an optical axis intersection of an incident surface and an exit surface with an outer diameter central axis in a resin lens. SOLUTION: A fixed mold 31 is rotatably supported by a substantially columnar eccentric insert 101 having a second optical functional surface forming portion on a tip surface thereof and an eccentric insert 101 around its central axis. It is provided with a support cylinder 102. In the eccentric insert 101, the second optical axis intersection portion of the second optical functional surface forming portion for forming the second optical axis intersection of the second optical functional surface of the resin lens 10 is relative to the central axis 112 of the eccentric insert 101. It is provided eccentrically. The support cylinder 102 is rotatably supported by the fixed mold 31 around the central axis of the support cylinder 102. The central axis of the eccentric insert 101 is eccentric with respect to the central axis of the support cylinder 102. [Selection diagram] FIG. 4

Description

  The present invention relates to a mold apparatus, an injection molding apparatus, an injection molding method, a resin lens, a resin lens manufacturing method, a lens unit, and a camera.

In recent years, resin lenses have been used in various fields. For example, pickup lenses for optical discs such as Blu-ray discs, DVDs, CDs, lenses for handy video cameras, parking assistance, lane departure warning, inter-vehicle distance control, collision prevention, driver monitoring, night night vision, pedestrian detection A resin lens is used as a lens of an in-vehicle camera used for blind spot monitoring or the like. In particular, recently, with the increase in the number of pixels of a sensor, a resin lens is often used to realize an aspheric lens having a high aberration correction capability.
The resin lens is resin-molded by an injection molding apparatus including at least two molds, a fixed mold and a movable mold. These two molds have, for example, a nest in a part for molding a lens. Further, in the multi-cavity method in which a plurality of resin lenses can be molded by a single molding, an injection molding apparatus having a plurality of inserts in each mold is used. Since the injection molding apparatus is constructed by assembling a relatively large number of parts including the inserts, when assembled (set up), the positions of the two molds and a pair of opposed ones provided in the respective molds. Deviation occurs in the nesting position.

  In the design stage of the aspherical lens, for example, the aspherical optical axis of the first surface of the lens and the aspherical optical axis of the second surface of the lens are set to coincide. However, in the injection molding apparatus, in the small-diameter resin lens used in the above-mentioned various fields, the position of the pair of opposing nests provided in each mold is shifted at the time of mold setup. In many cases, the optical axis of one aspherical surface does not coincide with the optical axis of the aspherical surface of the second surface of the lens, and the respective optical axes are shifted without passing through the center of the outer diameter of the lens. In the aspherical lens, the optical axis of each lens surface is uniquely determined from the shape of each lens surface on the first surface and the second surface. In the case of a spherical lens, the optical axis of each lens surface is not uniquely determined from the lens surface shape on the first surface and the second surface, and here is a spherical lens surface (optical functional surface). The normal passing through the center of the outer periphery of the spherical portion is called the optical axis. The center of the outer diameter of the lens is the center of the outer diameter of the lens, for example, the center of the circle when the outer periphery of the substantially circular lens is assumed to be a circle.

Here, in the fixed mold and the movable mold, each of the inserts can be rotated, and in each insert, the lens molding surface is shifted with respect to the rotation axis of the insert, and the rotation axis of the rotation of the insert And the optical axis of the lens surface (virtual optical axis on the lens molding surface) may be decentered. If there is a point that overlaps the trajectory of each optical axis when each nest is rotated, at the position of this overlapping point, the virtual optical axis of the lens molding surface of the nest that molds the first surface, and the second The rotational positions of the two nestings are adjusted so that the virtual optical axes of the lens forming surfaces of the nesting lenses that form the surfaces coincide with each other. In this case, the optical axes of the two lens surfaces coincide with each other, and the resolution of the resin lens can be improved.
However, in this case, the optical axis of the first surface and the optical axis of the second surface theoretically coincide with each other, but the optical axis does not coincide with the center of the outer diameter of the molded resin lens. Further, as described above, in the molding of the first surface and the second surface, the optical axis of the lens molding surface is decentered with respect to the rotation axis of the telescope, so that the outer diameter center of the molded resin lens is The optical axis shift of each surface becomes large, and the optical axes of the first surface and the second surface of the resin lens are shifted by 5 μm to 10 μm from the center of the outer diameter.
For example, when the resin lens is installed on the holder or the lens barrel on the basis of the outer diameter, the optical axis is shifted from the center axis of the holder or the lens barrel.

  In such a case, in various cameras using resin lenses, a plurality of resin lenses are installed in, for example, a lens barrel and used as a lens group (a series of lens systems). In this case, for example, when the optical axis of the lens is shifted with respect to the outer diameter center of the resin lens having a polygonal or circular outer shape (outer peripheral surface) in each lens, the position of the optical axis is different in each lens. The entire lens group causes a decrease in resolution (deterioration of MTF), resulting in poor product yield. In this case, each resin lens whose lens outer peripheral surface is positioned by the inner peripheral surface of the lens barrel is deviated from the optical axis of each resin lens with respect to the center (outer diameter center) of the outer peripheral surface. By rotating each of the plurality of resin lenses in the cylinder, the optical axes of the resin lenses can be collected as close to one axis as possible (alignment of the phases), thereby improving the resolution of the lens system. it can. However, it is difficult to align the optical axis by rotating each resin lens in each lens barrel, and even if it can be done, it takes time and cost. Further, even if the phases of the lenses are aligned as much as possible, there is no change in the optical axes of the lenses in the lens barrel, and there is a limit to the improvement of the optical characteristics.

  In addition, when there is a shift in the center of the entrance surface and the center of the exit surface of each plastic lens in the lens barrel, a composite lens in which two lenses of a base lens and a resin lens are bonded together is used. By adjusting the position of the center of the exit surface of the resin lens with respect to the center of the exit surface of the base lens in the compound lens, the amount of transmission eccentricity caused by the deviation between the center of the entrance surface and the exit surface of the plastic lens can be canceled by the entire lens system. It has been proposed (see Patent Document 1).

JP 2008-268876 A

  By the way, according to Patent Document 1, it is not necessary to rotate each plastic lens within the lens barrel, and in the compound lens, only the position of the resin lens with respect to the base lens is adjusted. The center of the entrance surface and the exit surface of the plastic lens is not close to one axis, and there is a limit to the improvement in resolution. Position adjustment is required, which is troublesome.

  The present invention has been made in view of the above circumstances, and in a resin lens, an injection molding apparatus, an injection molding method, a resin lens, and a resin capable of aligning the optical axes of the first surface and the second surface with the center of the outer diameter. It is an object to provide a lens manufacturing method, a lens unit, and a camera.

In order to solve the above problems, a mold apparatus of the present invention has a pair of molds for molding a resin lens having two optical functional surfaces, and one of the molds is A first optical functional surface molding part that molds one of the two optical functional surfaces inside the outermost periphery of the resin lens; and the other mold is the other of the resin lenses. A second optical functional surface molding part for molding the optical functional surface;
An outer peripheral molding part for determining the outer diameter of the resin lens by molding the outermost peripheral part of the outer side of the optical functional surface of the resin lens on one of the molds is provided,
The center of the outer diameter of the resin lens determined by the first optical axis intersection part of the first optical functional surface molding part that molds the optical axis intersection of one of the optical functional surfaces of the resin lens and the outer peripheral molding part The first optical functional surface molding part for molding the outer diameter center portion of the first optical functional surface molding part is arranged overlapping,
The other mold has a substantially cylindrical eccentric insert with the second optical functional surface molding portion provided on the front end surface thereof, and the eccentric insert is supported rotatably about the central axis of the eccentric insert. And a support cylinder
The eccentric nesting is such that the second optical axis intersection portion of the second optical functional surface molding portion that molds the optical axis intersection of the other optical functional surface of the resin lens is relative to the central axis of the eccentric nesting. Provided eccentrically,
The support cylinder is supported by one of the molds so as to be rotatable around a central axis of the support cylinder,
The center axis of the eccentric nest is eccentric with respect to the center axis of the support cylinder.

  According to such a structure, the surface which has one optical function surface of a resin lens is shape | molded by one metal mold | die. At this time, the first optical axis intersection part that molds the optical axis intersection of one optical function surface of the resin lens and the outer diameter center part that molds the outer diameter center of one optical function surface overlap each other at substantially the same position. Therefore, on one surface of the resin lens molded by this injection molding apparatus, there is basically an optical axis intersection at the center of the outer diameter of the resin lens, so the outermost circumference (outer diameter) of the resin lens is used as a reference. The position of the optical axis intersection can be adjusted. On the other hand, in the other mold that molds the other surface of the resin lens, the second optical function surface molding portion that molds the other optical function surface of the resin lens is formed on the tip surface of the eccentric insert. The second optical axis intersection portion of the second optical function surface molding portion that is rotatable with the child and that molds the other optical function surface with respect to the central axis that is the center of rotation of the eccentric insert is eccentric. In addition, the eccentric nest is rotatably supported, and a self-rotating support cylinder is provided so that the center axis serving as the center of rotation of the eccentric nest is eccentric with respect to the center axis serving as the center of rotation of the eccentric nest. By combining the rotation of the eccentric nest and the rotation of the support cylinder, the position of the second optical axis intersection part of the second optical functional surface molding part can be arranged at any position within the predetermined range. .

  Accordingly, when the mold apparatus is assembled, the first optical axis intersection part of the first optical functional surface molding part of one mold is positioned so as to overlap the central part of the outer diameter, and the second optical of the other mold It is possible to make the second optical axis intersection part of the functional surface molding portion coincide with the position overlapping the first optical axis intersection part or to be as close as possible. As a result, in the molded resin lens, the optical axis intersection of the two optical functional surfaces can be aligned with the center of the outer diameter, and the two optical elements can be placed on one axis of the resin lens (the substantial optical axis of the lens). It becomes possible to arrange the optical axis intersections of the functional surfaces, or to bring the optical axis intersections close to the one axis. In addition, the angle adjustment of the eccentric nest and the support cylinder is, for example, repeatedly performing the injection molding after adjusting the angle, for example, adjusting the angles of the support cylinder and the eccentric nest so that the optical characteristics are improved, These angles can be narrowed down. Alternatively, the position of the optical axis intersection may be directly measured and adjusted so that the position of the optical axis intersection of the molded resin lens is on the center of the outer diameter of the resin lens. In addition, when a lens unit such as a camera is configured by a series of resin lens groups by combining a plurality of types of resin lenses of the present invention, each of the resin lenses is positioned on the inner peripheral surface of the lens barrel. All of the optical axis intersections of the resin lenses can be arranged on one axis or close to this axis. At this time, in each resin lens, the optical axis intersection is arranged at or close to the center of the outer diameter, so that the optical axis intersection of the resin lens can be adjusted only by setting the resin lens in the lens barrel. Yes, when installing resin lenses on the lens barrel, there is no need to rotate the resin lens to align the optical axis intersection of each resin lens, improving the optical characteristics of the resin lens group and saving assembly work And cost reduction based on it.

  In the single lens (one resin lens), the intersection between the optical axis of each optical functional surface and the optical functional surface is defined as an optical axis intersection. Here, as described above, in the resin lens, the first optical functional surface molding portion and the second optical functional surface molding portion in the pair of molds at the time of injection molding are respectively displaced with respect to the outer diameter center of the resin lens. As described above, the optical axis of the optical function surface is shifted, and the intersection of the optical axes of the two optical function surfaces is aligned with the center of the outer diameter as described above. It should be noted that the center of the outer diameter and the optical axis intersection of each optical function surface do not have to be completely coincident with each other, and may be set to be within a set allowable range.

  In the above-described configuration of the present invention, the one mold is provided with a substantially cylindrical insert having the first optical functional surface molding portion provided on the front end surface so as to be rotatable around the central axis of the insert. Preferably, the first optical axis intersection part of the first optical functional surface molding part is provided on the central axis of the insert.

  According to such a configuration, it is possible to finely adjust various errors such as manufacturing errors by rotating the insert with one mold. That is, when the shape of the molding surface deviates from the design due to various errors, it is possible to perform fine adjustment by rotating the insert, and the optical characteristics of the resin lens can be improved.

Further, in the configuration of the present invention, the molding surface for molding the resin lens of the other mold has an opening that exposes the tip surface of the eccentric insert,
The eccentric insertion based on the rotation around the central axis of the support cylinder that is eccentric with respect to the central axis of the eccentric insert between the inner peripheral edge of the opening and the outer peripheral edge of the tip end surface of the eccentric insert. It is preferable that a gap allowing the deflection of the child is provided.

  According to such a configuration, the eccentric insert rotates together with the support cylinder around the center axis of the support cylinder that is eccentric with respect to the central axis of the eccentric insert, so that the eccentric insert becomes the center of the eccentric insert. The opening on the molding surface of the other mold that exposes the tip face of the eccentric insert of the other mold will be wider than the tip face of the eccentric insert, and will move over a wider range than the tip face. By providing a gap between the outer peripheral edge of the front end surface of the lens and the inner peripheral edge of the opening to allow the eccentric insert to swing based on the eccentricity of the center of rotation of the support cylinder with respect to the central axis of the eccentric insert, The eccentric nest can be rotated by rotating the. At this time, if the gap between the inner peripheral edge of the opening of the molding surface and the outer peripheral edge of the tip end surface of the eccentric insert becomes too large, resin flows into the gap during molding, resulting in burrs. It is preferable that the above-mentioned gap is narrow so as not to flow in. In this case, it is preferable that the diameter of the optical functional surface of the resin lens is small, and if the diameter of the second optical functional surface molding portion is small based on the size of the resin lens, the above-described gap becomes narrow, and the resin is not burrs. It can be prevented from flowing into the gap. Further, the moderate gap functions as an air vent (gas vent) when filling the mold with the resin, and can smoothly fill the resin by discharging the gas in the mold.

  In the configuration of the present invention, the distance between the central axis of the eccentric insert and the central axis of the support cylinder is such that the central axis of the eccentric insert and the second optical axis of the eccentric insert. It is preferable that the distance is less than or equal to the intersection point.

  According to such a configuration, the distance between the central axis of the eccentric nesting and the central axis of the support cylinder is R1, and the second axis of the eccentric nesting and the second light of the eccentric nesting When the distance from the axis intersection part is R2, by setting R1 ≦ R2, the radius R1 + with the second optical axis intersection part of the second optical function surface molding portion as the center axis of the support cylinder It can be placed in the circle of R2. In addition, even if the combination of the angle of the support cylinder and the angle of the eccentric telescope is different, the second optical axis intersection part is efficiently formed so that the positions of the second optical axis intersection parts do not overlap and become the same. In order to be movable, it is preferable that R1 = R2, and one second optical axis is provided for one combination of the angle of the support cylinder and the angle of the eccentric telescope except for the position serving as the center axis of the support cylinder. The position of the intersection point is determined, and the angle adjustment between the support cylinder and the eccentric nest can be made efficient.

  The injection molding apparatus of the present invention includes the mold apparatus of the present invention, a mold opening / closing part that opens and closes the one mold and the other mold, the first optical functional surface molding part, and the second optical unit. And a molten resin supply unit that supplies the molten resin to a cavity partitioned by the functional surface molding unit and the outer peripheral molding unit. According to this injection molding apparatus, as described above, the resin lens can be manufactured so that the position of the optical axis intersection of the two optical functional surfaces is aligned with the center of the outer diameter.

The injection molding method of the present invention is an injection molding method of molding a resin lens using the mold apparatus of the present invention,
After assembling the injection molding apparatus including the pair of molds, the second optical axis intersection part of the second optical functional surface molding part is located at the first optical axis intersection part of the first optical functional surface molding part. The support cylinder is rotated about the central axis with respect to the other mold so as to overlap, and the eccentric nest is rotated about the central axis with respect to the support cylinder.

  According to such a configuration, when the resin lens is molded, it is possible to place the optical axis intersection of the two optical functional surfaces on the center of the outer diameter of the resin lens. The optical axis intersection of the two optical functional surfaces of the resin lens is preferably arranged so as to overlap the center of the outer diameter, but if the position of the optical axis intersection can be brought closer to the outer diameter center, the outer diameter center And the optical axis intersection point may be separated within a set allowable range.

The resin lens of the present invention is a resin lens having a first surface and a second surface, and having an optical functional surface on each of these surfaces,
The optical axis intersection of each of the two optical functional surfaces is disposed at a position of 2 μm or less from the center of the outer diameter,
On one surface of the first surface and the second surface, a substantially annular and parting line-shaped ridge is provided inside the outer peripheral surface,
The protrusion is characterized in that the total width of the protrusions facing each other across the optical axis intersection is constant at an arbitrary position.

According to such a configuration, the above-described gap between the outer peripheral edge of the distal end surface of the eccentric insert and the inner peripheral edge of the surrounding opening is formed by molding the resin lens by the above-described mold device or the injection molding method. The parting line-shaped ridge is formed so as to substantially surround the portion formed on the tip surface of the eccentric nest of the resin lens, but the optical axis intersection of the two optical functional surfaces at the center of the outer diameter of the resin lens Thus, the distance between the two optical axis intersection points when the optical axis intersection point of each optical functional surface is projected onto one plane orthogonal to the optical axis direction can be reduced. As a result, the fact that there is an annular parting line-like protrusion not on the other surface on one surface of the two surfaces, the optical axis intersection of the two optical function surfaces as described above It can be used to identify the resin lens close to the center of the outer diameter.
The inner periphery of the ridge corresponds to the outer peripheral edge of the tip surface of the eccentric nesting, and the outer periphery of the ridge is provided on the molding surface for molding the resin lens of the other mold, and the tip surface of the eccentric nesting This corresponds to the inner peripheral edge of the opening that exposes. In this case, if the tip surface of the eccentric nest in the opening is arranged at the center of the opening, the width of each part of the ridge is the same, but in practice, the outer peripheral edge of the tip surface is the inside of the opening. It will be in the state which contacted either of the periphery substantially, and the width | variety of a protrusion will change with the location of a protrusion. However, the sum of the widths of the two ridges along the radial direction passing through the optical axis intersection of the ridge is the diameter of the outer peripheral edge of the tip surface of the eccentric insert and the diameter of the opening exposing the tip surface. The absolute value of the difference is obtained, and the sum of the widths of the two locations of the above-described protrusion is constant regardless of the diameter in any direction. In other words, the total width of the protrusions facing each other across the optical axis intersection is constant at an arbitrary position.

  The parting line refers to a line (surface) where two molds are separated, and also refers to a linear protrusion (projection) formed on the mold separation line of the molded product, Here, the parting line is a protrusion formed on the molded product, and the line from which the mold is separated is called a separation surface.

In the resin lens having the above-described configuration of the present invention,
The optical functional surfaces of the first surface and the second surface are preferably aspheric surfaces.
According to such a configuration, a resin lens having high aberration correction capability can be obtained.

The method for producing the resin lens of the present invention includes:
The resin lens is manufactured using the mold apparatus of the present invention.
According to such a configuration, the resin lens can be manufactured so that the position of the optical axis intersection of the two optical functional surfaces is aligned with the center of the outer diameter as described above.

The lens unit of the present invention has a first surface and a second surface, each of which has an optical functional surface having an optical axis intersection, and the optical axis intersection of each of the two optical functional surfaces is the center of the outer diameter. And approximately one part of the first surface and the second surface on the outer side of the optical function surface and on the inner side of the outer peripheral surface so as to have a parting line shape. A plurality of resin lenses having protrusions whose total value of the widths of two locations facing each other across the optical axis intersection is constant at an arbitrary position;
Since the plurality of resin lenses are respectively press-fitted into the lens barrel and positioned, all the optical axis intersections of the plurality of resin lenses are disposed at a position of 2 μm or less from the center line of the lens barrel. Features.
According to such a configuration, by molding the resin lens by the above-described injection molding apparatus or injection molding method, the above-described gap between the outer peripheral edge of the distal end surface of the eccentric nest and the inner peripheral edge of the surrounding opening. The parting line-shaped ridge is formed so as to substantially surround the portion formed on the tip surface of the eccentric nest of the resin lens, but the optical axis intersection of the two optical functional surfaces at the center of the outer diameter of the resin lens Can be brought closer. And by press-fitting each resin lens into the lens barrel, even if each resin lens has a different surface shape and diameter, the optical axis intersection of each optical function surface is adjusted to 2 μm or less with respect to the outer diameter center. The optical axis intersection of each resin lens can be aligned with the center line (inner diameter center) of the lens barrel, and each optical axis intersection can be arranged at 2 μm or less from the center line. Thereby, the resolution of the lens unit can be “increased at low cost.

  The camera according to the present invention includes the lens unit according to the present invention, and an image sensor is provided on a side of connecting the images of the lens unit.

  According to such a configuration, the resolution of the lens unit can be increased at a low cost, and a camera with good performance can be manufactured at a low cost.

  According to the present invention, the optical characteristic of the resin lens can be improved by bringing the optical axis intersection of the entrance surface and the optical axis intersection of the exit surface close to the center of the outer diameter of the resin lens.

It is a front view which shows the 1st surface of the resin lens of embodiment of this invention. It is a rear view which shows the 2nd surface of a resin lens similarly. It is sectional drawing along the optical axis which shows a resin lens equally. It is a schematic sectional drawing which shows the principal part of the metal mold | die apparatus which shape | molds a resin lens equally. It is a figure which shows the 2nd shaping | molding surface of an eccentric nest | insert. It is a figure which shows the 1st shaping | molding surface of a nesting same as the above. It is a front view which shows the eccentric nesting part of the isolation | separation surface of a fixed metal mold | die. It is principal part sectional drawing which shows the eccentric nest | insert of a metal mold apparatus, and a support cylinder. Explain the relationship between the rotation center of the support tube, the rotation center of the eccentric insert, the second optical axis intersection part of the second optical functional surface molding part of the eccentric insert, and the movement range of the second optical axis intersection part It is a figure for doing. It is a figure which shows a part of locus | trajectory of a 2nd optical axis intersection site | part similarly. It is a figure which shows the outline of a lens unit and a camera provided with a resin lens. FIG. 3 is a cross-sectional view of a principal part along the optical axis of the resin lens. It is a figure which shows the outline of an injection molding apparatus similarly.

Hereinafter, a mold apparatus, an injection molding apparatus, an injection molding method, a resin lens, a resin lens manufacturing method, a lens unit, and a camera according to an embodiment of the present invention will be described with reference to the drawings.
First, the resin lens according to the present embodiment will be described. 1-3 show the resin lens 10 of this example, FIG. 1 shows the first surface 11 of the resin lens 10, FIG. 2 shows the second surface 12 of the resin lens 10, and FIG. 3 shows the resin lens. 10 shows a cross section along 10 optical axes 24.

The resin lens 10 is formed by injection molding, and a plurality of resin lenses 10 are obtained from one molded product (for example, four or eight).
A molded product including the resin lens 10 is directed to a plurality of cavities from the sprue, sprue from which the resin is injected, in order to guide the resin (for example, thermoplastic resin) to the cavity in which the resin lens 10 is molded in an injection molding apparatus. The runner for branching and distributing the resin into each cavity and the gate between the runner and the cavity are molded. Therefore, each resin lens 10 molded in the cavity portion is connected to a runner portion molded by a runner, a sprue portion molded by a sprue, or another resin lens 10 via a gate portion molded by a gate. In the resin lens 10, the gate portion protruding from the outer periphery of the resin lens 10 is cut inside the outer periphery to obtain a finished product. Therefore, the molded product immediately after injection molding includes a plurality of resin lenses 10 that are taken in large numbers, a gate portion, a runner portion, and a sprue portion.

  Further, the mold apparatus has two molds as shown in FIG. 4, and includes a movable mold (one mold) 32 and a fixed mold (the other mold) 31, and is fixed during molding. The part (cavity) filled with the resin that becomes the resin lens 10 is brought into a substantially hermetically sealed state with the mold 31 and the movable mold 32 being brought into contact with each other, and after the resin is filled, the molded product is solidified to some extent after being cooled. By moving the movable mold 32 away from the mold 31 and opening the mold, the resin-filled portion is opened and the resin lens 10 is taken out. At this time, the resin lens 10 is released from the fixed mold 31 of the fixed mold 31 and the movable mold 32 that are generally opened, and is held by the movable mold 32.

  In the present embodiment, the outer peripheral surface 19 of the resin lens 10 is formed by the movable mold 32 of the fixed mold 31 and the movable mold 32. The outer peripheral surface 19 is formed in an outer peripheral forming portion 150 (shown in FIG. 4) of the movable side plate 37 of the movable mold 32. Thereby, the outer diameter of the resin lens 10 to be molded is determined by the outer peripheral molding portion 150 of the movable mold 32.

  Moreover, the resin lens 10 has the 1st surface 11 and the 2nd surface 12, and when the 1st surface 11 is made into the front, a 2nd surface is located in the back side of a 1st surface. A first optical functional surface 13 is provided on the first surface, and a first flange surface 15 is provided outside the first optical functional surface 13. A second optical functional surface 14 is provided on the second surface 12, and a second flange surface 16 is provided outside the second optical functional surface 14. In addition, the optical function part which has the 1st optical function surface 13 and the 2nd optical function surface 14 has optical functions, such as making it parallel light, condensing, and diffusing with respect to light, for example It is. In the present embodiment, the first optical functional surface 13 and the second optical functional surface 14 have an aspherical shape, and the resin lens 10 is an aspherical lens. The flange portion having the first flange surface 15 and the second flange surface 16 is used for mounting the resin lens 10, positioning, and the like.

  The first optical function surface 13 has a first optical axis intersection 17 through which the optical axis of the first optical function surface 13 passes, and the second optical function surface 14 has an optical axis of the second optical function surface 14. There is a second optical axis intersection 18 through. That is, the intersection of the first optical functional surface 13 and the optical axis 24 of the first optical functional surface 13 is the first optical axis intersection 17, and the optical axis 24 of the second optical functional surface 14 and the second optical functional surface 14 Is the second optical axis intersection 18. Here, in the design stage of the resin lens 10 of the present embodiment, the outer periphery 25 of the first optical functional surface 13 and the outer peripheral surface 19 of the resin lens 10 are concentric, and the outer periphery 26 of the second optical functional surface 14 The outer peripheral surface 19 of the resin lens 10 is also concentric. The center of the first optical functional surface 13 whose outer periphery 25 is circular is the first optical axis intersection point 17, and the center of the second optical functional surface 14 whose outer periphery 26 is circular is the second optical axis intersection point 18. The first optical axis intersection point 17 and the second optical axis intersection point 18 are disposed at the center of the outer peripheral surface 19 of the resin lens 10. In other words, the positions of the optical axis 24 and the center of the outer diameter of the resin lens 10 in FIGS. The optical axis 24 is shown by combining the optical axis of the first optical functional surface 13 and the optical axis of the second optical functional surface 14, but these optical axes are deviated within an allowable range.

  However, as described above, the optical axis of each surface coincides with the center of the outer diameter in terms of design. However, in practice, manufacturing errors, in particular, the molds after the fixed mold 31 and the movable mold 32 are set up are set. The shift causes a shift in the position of the first optical axis intersection 17 and the second optical axis intersection 18 (the position of the optical axis 24) and the center of the outer diameter. In this embodiment, as described later, when the resin lens 10 is molded, The shift is suppressed and made small. The center of the first optical function surface 13 whose outer periphery 25 is circular is the first optical axis intersection point 17, and the center of the second optical function surface 14 whose outer periphery 26 is circular is the second optical axis intersection point 18. Therefore, even if the first optical functional surface 13 and the second optical functional surface 14 are spherical surfaces, the respective optical axes 24 pass through the first optical axis intersection point 17 and the second optical axis intersection point 18.

Further, the resin lens 10 is provided with, for example, a gate mark 23 in which the gate portion is linearly removed inside the outer peripheral surface 19 at a portion where the gate portion is removed. In the resin lens 10, a portion where the gate mark 23 remains is previously formed in a straight line inside a circle that is an outer periphery.
Further, the second flange surface 16 of the second surface 12 formed by the fixed mold 31 of the resin lens 10 protrudes toward the second surface 12 of the resin lens 10 to form a substantially circular protrusion having a parting line shape. 21 is provided. The protrusion 21 is derived from a gap provided on a molding surface for molding the resin lens 10 of the fixed mold 31 for enabling the movement of the eccentric nest 101 as described later.

In the present embodiment, the first surface 11 is molded with the movable mold 32 together with the outer peripheral surface of the resin lens 10. At least the first optical functional surface 13 of the first surface 11 is formed by the insert 103 of the movable mold 32. The first optical axis intersection 17 of the resin lens 10 is formed by the central portion of the circular tip surface of the insert 103 of the movable mold 32, and the outer peripheral surface 19 of the resin lens 10 is formed by the movable side plate 37 surrounding the insert 103. Is done. There is almost no gap between the outer peripheral edge of the distal end surface of the insert 103 and the inner peripheral edge of the opening where the distal end surface of the insert 103 of the movable side plate 37 is exposed. Thereby, in the first surface 11 which is an aspheric surface of the resin lens 10, the optical axis of the first surface 11 substantially coincides with the center (outer diameter center) of the outer peripheral surface 19 and passes through the first optical axis intersection point 17. The positional deviation of the first optical axis intersection point 17 with respect to the center of the outer diameter can be extremely small, for example, can be made smaller than 1 μm, and further can be made 100 nm or less.
That is, the movable mold 32 is formed by rotating the concave surface at the tip of the insert 103 with an aspherical processing machine. Therefore, it is easy to match the center of the insert 103 with the first optical axis intersection point 17. Since the nest 103 is inserted into the hole of the movable side plate 37 without a substantial gap, the nest 103 and the movable side plate 37 are not displaced from each other.

  On the other hand, in the second optical function surface 14, it is possible to move the position of the second optical axis intersection 18 as described later to match the outer diameter central axis or the first optical axis intersection 17, and the outer diameter The distance from the central axis and the first optical axis intersection point 17 can be 2 μm or less, and in a direction orthogonal to the optical axis from the first optical axis intersection point 17 to the second optical axis intersection point 18 when viewed from the front. The distance can be 2 μm or less. Furthermore, the second optical axis intersection 18 can be brought closer to the outer diameter central axis and the first optical axis intersection 17, and the above-mentioned distance can be set to 1 μm or less. In this case, the outer diameter of the resin lens is, for example, 20 mm or less, and preferably 2 mm to 15 mm.

As shown in FIG. 4, the mold apparatus used for molding the resin lens 10 includes a fixed mold 31 and a movable mold 32 that can be opened and closed with respect to the fixed mold 31. FIG. 4 shows a state where the movable mold 32 is abutted against the fixed mold 31 and the movable mold 32 is closed. The right side in the figure is the fixed mold 31 and the left side is the movable mold with the separation surface 33 as a boundary. The mold 32 is used. Here, in the fixed mold 31 and the movable mold 32, the separation surface 33 side is the front end (front end) side, and the opposite side is the rear end (base end) side. Further, the tip surfaces of the fixed mold 31 and the movable mold 32 are referred to as separation surfaces 33, respectively.
The fixed mold 31 has a mounting plate (not shown) on the opposite side of the separation surface 33, a mold plate 34 is provided on the separation surface 33 side, and a fixed side plate 36 on the separation surface 33 side of the mold plate 34. Is provided. The template 34 is a part to which various members are attached, and determines the position of the fixed movable plate 36, guide pins (not shown) that guide the opening and closing movement of the movable mold 32, and the closed movable mold 32. Positioning pins (not shown) and the like are provided.
The mold plate 34 of the fixed mold 31 is provided with a support cylinder (sleeve insert) 102 that is rotatable with respect to the mold plate 34 and an eccentric insert 101 that is rotatable with respect to the support cylinder 102. Yes.

  The support cylinder 102 is a cylindrical member by including a columnar hollow portion that is disposed in a state where the eccentric insert 101 passes through the columnar member, but the central axis of the columnar support cylinder 102 On the other hand, the central axis of the cylindrical hollow portion is eccentric. That is, these central axes are parallel to each other but are out of position. The support cylinder 102 is rotatably disposed in a cylindrical space provided in the template 34 via a ball slider 41. The ball slider 41 is a cylindrical sphere holder in which a large number of spheres are arranged side by side in the axial direction and the circumferential direction, and the spheres are rotatably held. A cylindrical member arranged so as to be in contact with the sphere can be smoothly rotated around the central axis with little resistance. Therefore, the support cylinder 102 is rotatable with respect to the template 34. The central axis of the support cylinder 102 serving as a rotation axis at this time is along a direction orthogonal to the separation surface 33 described above. Note that the outer peripheral side of the ball slider 41 is in a state where almost all the balls are in contact with the inner peripheral surface of the cylindrical space of the template 34.

  A ball slider 46 is provided inside the support cylinder 102, and the eccentric insert 101 is rotatably supported by the support cylinder 102 via the ball slider 46. The ball slider 46 has the same configuration except that the diameter is smaller than that of the ball slider 41. In the ball slider 46, an eccentric nested rotating portion 45 described later of the eccentric nested 101 is inserted. In this state, the ball slider 41 that rotatably supports the support cylinder 102 and the central axis (rotation axis) of the support cylinder 102 substantially coincide with each other, and the eccentric insert 101 is rotatable with respect to these central axes. The center axis (rotation axis) of the ball slider 46 to be supported on the center axis and the center axis (rotation axis) of the eccentric insert 101 are eccentric. The center axis of the ball slider 46 and the center axis of the eccentric insert 101 coincide with each other. These central axes are all orthogonal to the separation surface 33.

  The distal end surface of the eccentric nest 101 is a second molding surface 43 that molds the first surface 11 of the resin lens 10. Further, the eccentric insert 101 is rotatably supported by a cylindrical eccentric insert main body portion 44 having the same diameter as the tip end surface and a mold plate 34 of the fixed mold 31 via a ball slider 46 from the tip end side. And a cylindrical eccentric nested rotating portion 45.

  The second molding surface 43 of the eccentric nest 101 is a second optical function surface molding portion 131 (shown in FIG. 5) whose center side portion molds the second optical function surface 14 of the resin lens 10, and its outer side is A second flange forming portion 132 (shown in FIG. 5) for forming a part of the inner peripheral side of the second flange surface 16 is formed. The fixed mold 31 does not have a portion for molding the outer peripheral surface 19 of the resin lens 10. In the present embodiment, the second molding surface 43 of the tip end surface of the eccentric insert 101 is the second surface of the resin lens 10. Twelve second optical functional surfaces 14 and inner peripheral portions of the second flange surface 16 are molded. Note that the outer peripheral side portion of the second flange surface 16 is formed by a fixed side plate 36 around the eccentric insert 101.

Further, as schematically shown in FIG. 7, between the inner peripheral surface of the opening portion of the through hole into which the eccentric nested main body portion 44 of the fixed side plate 36 is inserted and the outer peripheral surface of the eccentric nested main body portion 44. Is provided with a gap that allows the eccentric insert 101 to rotate smoothly while allowing the deflection of the eccentric insert 101 due to the eccentricity of the center axis of the support cylinder 102 and the center axis of the eccentric insert 101. Yes. The gap is such that resin does not enter during injection molding and no burrs are generated, but the parting line-shaped protrusions 21 are formed in the resin lens 10 based on the gap. Further, this gap has an effect of degassing during injection molding and smoothing the resin injection molding.
However, as schematically shown in FIG. 12, the diameter of the eccentric nested main body 44 may be formed to be larger than the diameter of the resin lens 10 to be molded (the outer diameter of the cavity portion). In this case, the boundary (gap) between the inner peripheral surface of the opening portion of the through hole in the fixed side plate 36 and the outer peripheral surface of the eccentric nested main body 44 is positioned on the radially outer side of the resin lens 10 to be molded. It becomes. Therefore, the protrusion 21 is not formed on the resin lens 10.

  In addition, a groove 38 serving as a runner and a groove 39 serving as a thinner gate are provided on the fixed plate 36 of the fixed mold 31 so as to face the movable plate 37. Further, the movable plate 37 of the movable mold 32 is provided with a groove 54 serving as a runner together with the groove 38 and a groove 53 serving as a gate together with the groove 39. The fixed side plate 36 may be provided only on the movable side plate 37 without providing the groove 38 serving as a runner and the groove 39 serving as a gate.

The movable mold 32 is movable between a state in which it is abutted against the fixed mold 31 and is closed and a state in which the movable mold 32 is opened away from the fixed mold 31 in a direction perpendicular to the separation surface 33. The movable mold 32 is provided with a movable attachment plate (not shown) on the opposite side of the separation surface 33, and a movable mold plate 35 is provided on the separation surface 33 side of the attachment plate. A movable side plate 37 up to the separation surface 33 is provided on the separation surface 33 side.
The movable side mold plate 35 is provided with a bush (not shown) into which the above-described guide pins and positioning pins extending from the fixed mold 31 perpendicular to the separation surface 33 are inserted. Further, there is provided a device (not shown) for extruding a molded product including a plurality of resin lenses 10 held by the movable mold 32 when the mold is opened after resin molding.
Further, the template 35 is provided with a through hole for rotatably holding the insert 103, and the insert 103 in a state of being inserted into the cylindrical ball slider 64 is disposed in the through hole. It is supported by the template 35 via a ball slider 64 so as to be rotatable. Further, the movable plate 37 on the separation surface 33 side of the template 35 is provided with a through hole into which the insert main body portion 58 on the distal end side of the insert 103 is inserted. The front end surface is exposed to the separation surface 33 side.

The nest 103 is provided with a movable first molding surface 57 that molds the first surface 11 of the resin lens 10 on the front end surface, and in the order from the front end surface to the rear end side, a cylindrical shape having the same diameter as the front end surface. A telescoping main body 58, a cylindrical telescoping rotation part 59 having a larger diameter than the telescoping main body part 58, and a disc-shaped telescoping base end part 60 having a larger diameter than the telescoping rotation part 59 are provided. Each part of these inserts 103 is arranged on the same axis.
The first molding surface 57 has a first optical function surface molding portion 142 (shown in FIG. 6) whose center portion molds the first optical function surface 13 of the resin lens 10 and a first outer side of the first optical function surface 13. A first flange forming portion 143 (shown in FIG. 6) for forming a part of the inner peripheral side of the flange surface 15 is provided. Further, a part of the outer peripheral side of the first flange surface 15 is formed by a part of the movable side plate 37 outside the first forming surface 57.

A first optical axis intersection portion 140 (shown in FIG. 6), which forms the first optical axis intersection point 17 of the first optical functional surface 13 of the resin lens 10 on the first molding surface 57, is on the central axis of the nest 103. Thus, it is arranged on the rotation axis coinciding with the central axis, and is arranged at the center of the first optical function surface molding portion at the center of the first molding surface 57. Such an arrangement basically aligns the insert 103, the hole for storing the insert 103, and the center of the molding surface of the insert 103, and can be easily performed.
Further, the outer diameter of the resin lens 10 is molded by the outer peripheral molding portion 150 constituted by the inner peripheral surface of the opening that exposes the distal end surface of the insert 103 of the movable side plate 37. That is, the outer diameter of the resin lens 10 is defined by the movable mold 32 that molds the first surface 11 having the first optical functional surface 13 of the resin lens 10.
Here, since the nest 103 has the above-mentioned first optical axis intersection part 140 on its rotation axis, basically the first optical axis intersection part 140 does not move even if the nest 103 rotates. However, there is a possibility of movement within an error range such as a manufacturing error. Further, since the insert 103 only rotates and does not shake during rotation unlike the eccentric insert 101, the inner peripheral surface of the through hole of the movable side plate 37 and the insert main body 58 of the insert 103 There is no gap between the outer peripheral surface and the outer surface so as to allow vibration, and the gap is sufficient to allow smooth rotation.

  The insert body 58 is a portion having the first molding surface 57 at the tip as described above. The insert rotation part 59 is a part that is inserted into the ball slider 64 and supported by the ball slider 64 in a self-rotating manner. The ball slider 64 has the same configuration as that of the ball slider 41 except that the diameter is different. In the ball slider 64, almost all the balls of the ball slider 64 come into contact with the telescopic rotating portion 59, so that the movable side plate Almost all the balls of the ball slider 64 are in contact with the inner peripheral surface of the through hole into which the 37 inserts 103 are inserted.

Here, in the movable mold 32, the insert 103 is basically rotated for error adjustment of the first molding surface 57, and the first surface of the resin lens 10 even if the insert 103 is rotated. The position of the first optical axis intersection portion 140 for molding the first optical axis intersection point 17 of the first optical function surface 11 is almost unchanged, and is at the position for molding the center of the outer diameter of the resin lens 10.
On the other hand, in the fixed mold 31, the support cylinder 102 that rotatably supports the eccentric nest 101 via the ball slider 46 is rotatably supported on the mold plate 34 of the fixed mold 31 via the ball slider 41. Further, the rotation axis (center axis) of the support cylinder 102 is eccentric with respect to the rotation axis (center axis) of the eccentric insert 101, and the second optical axis intersection portion 113 (see FIG. 8), the rotation axis (center axis) of the eccentric insert 101 is eccentric, so that the second optical axis intersection portion is within a predetermined range by rotating the eccentric insert 101 and the support cylinder 102 respectively. 113 can be moved arbitrarily.

  FIG. 5 shows the second molding surface 43 of the fixed mold 31, and the second optical axis intersection portion 113 is eccentric from the rotation shaft 112 of the eccentric insert 101. Moreover, the center part of the 2nd shaping | molding surface 43 is made into the 2nd optical function surface shaping | molding part 131 as mentioned above, and the outer side is made into the 2nd flange shaping | molding part 132. FIG. FIG. 6 shows the first molding surface 57 of the movable mold 32, and the outer diameter center that is the intersection of the first optical axis intersection portion 140 and the outer diameter center of the first surface 11 of the resin lens 10 is molded. The outer diameter central region 141 is in a state of matching. Further, the central portion of the first molding surface 57 is a first optical functional surface molding portion 142, and the outside thereof is a first flange molding portion 143. Further, the rotating shaft 112 (illustrated in FIG. 8) of the insert 103 and the outer diameter center portion 141 coincide with each other.

  In the present embodiment, since R1 = R2 as described above, the second optical axis intersection portion 113 can be moved anywhere within the circular range of the radius R1 + R2. In the injection molding apparatus, the mold is set up. Even if an error occurs, the second optical axis intersection portion 113 of the fixed mold 31 can be aligned with the first optical axis intersection portion 140 of the movable mold 32 after the setup.

Next, an injection molding method of the resin lens 10 using the mold apparatus of the present embodiment will be described. First, the movable mold 32 and the fixed mold 31 of the mold apparatus are set up so that the resin lens 10 can be molded.
Next, the resin lens 10 is prototyped. At this time, the angles of the eccentric insert 101 and the support cylinder 102 are appropriately adjusted based on the deviation between the insert 103 and the eccentric insert 101. A prototype may be made without adjustment.

Next, the outer diameter of the prototype resin lens 10 and the center of the second optical functional surface 14 of the second surface 12 formed by the movable mold 32 are measured with a three-dimensional shape measuring instrument. Next, the center of the first optical functional surface 13 and the center of the second optical functional surface 14 are measured with a three-dimensional shape measuring instrument. Next, as the measurement result, the angles of the eccentric nest 101 and the support cylinder 102 are adjusted based on the displacement of the center of the first optical function surface 13 and the center of the second optical function surface 14.
Next, the resin lens 10 is prototyped again. By repeating this trial manufacture, measurement, and angle adjustment of the eccentric nest 101 and the support cylinder 102, the shift amount between the center of the first optical function surface 13 and the center of the second optical function surface 14 is within a predetermined common range. In this case, the trial production of the resin lens 10 is finished.
As a result, it is possible to set the deviation of the positions of the outer diameter center, the first optical axis intersection point 17 and the second optical axis intersection point 18 to 2 μm or less. Thus, after adjusting the angle of the eccentric nest 101 and the support cylinder 102, mass production of the resin lens 10 is started, and the injection molding is sequentially repeated.

The injection-molded resin lens 10 has the above-described eccentric insert 101 between the outer peripheral edge of the distal end surface of the above-described eccentric insert 101 and the inner peripheral edge of the opening through which the eccentric insert 101 of the fixed side plate 36 is exposed. A parting line-like substantially annular ridge 21 is formed by a gap for allowing deflection. The protrusion 21 formed only on one surface (second surface) of the resin lens 10 causes the resin lens 10 to have the first optical axis intersection 17 and the second optical axis intersection with respect to the outer diameter central axis as described above. 18 can be distinguished from each other, and it becomes easy to distinguish and use the resin lens whose optical axis intersection is greatly deviated from the central axis of the outer diameter.
In addition, it is preferable that the protrusion 21 is outside the first optical functional surface 13 and the second optical functional surface 14.

  FIG. 7 is a main part front schematic view showing the separation surface 33 side of the fixed mold 31 that is abutted against the movable mold 32, and the eccentric insert 101 is inserted from the opening of the hole provided in the fixed plate 36. The second molding surface 43 of the child main body 44 is visible. Note that FIG. 7 is a schematic view, and illustrations of concavities and convexities corresponding to the shape of the resin lens 10 on the front surface (separation surface 33) of the second molding surface 43 and the fixed side plate 36 are omitted.

In FIG. 7, the above-described gap that allows the eccentric nest 101 to move is provided between the eccentric nest 101 and the fixed side plate 36. For example, if the difference between the inner diameter of the opening portion of the hole into which the eccentric insert 101 is inserted and the outer diameter of the eccentric insert main body 44 of the shorter eccentric insert 101 is 10 μm, for example, When the eccentric nest 101 is arranged to be biased to one of the holes, a maximum gap of 10 μm is formed. This gap amount is set so that the resin does not flow into the gap in consideration of the viscosity of the resin. A burr on the protrusion 21 portion having a slight height (which does not affect the lens joining) may occur.
From this, the protrusion 21 generated in the resin lens 10 has an arbitrary total width (sum of two widths) of the protrusions 21 facing each other across the second optical axis intersection 18 aligned with the center of the outer diameter. At any position (any position).

  FIG. 8 is a cross-sectional view taken along the line AA of FIG. 4 of the eccentric insert rotating portion 45 of the eccentric insert 101 of the fixed mold 31 of the mold apparatus, and is a cross-sectional view orthogonal to the rotation axis, from the center side. These are an eccentric telescope rotating portion 45 of the eccentric telescope 101, a ball slider 46 for the eccentric telescope 101, a support cylinder 102, a ball slider 41 for the support cylinder 102, and a template 34. Although the ball sliders 41 and 46 are illustrated as annular spaces, they actually have a sphere holder and a sphere. The rotation center axis (center axis) 111 of the support cylinder 102 is indicated by +, the rotation center axis (center axis) 112 of the eccentric insert 101 is indicated by X, and the first of the eccentric insert 101 (second molding surface 43). The two optical axis intersection part 113 is indicated by O. In this embodiment, the second optical axis intersection portion 113 is defined by the eccentricity of the positions of the rotation shaft 111 of the support cylinder 102, the rotation shaft 112 of the eccentric insert 101, and the second optical axis intersection portion 113. It can be moved to any position within a predetermined range. For example, as shown in FIG. 9, when the support cylinder is fixed so that the center axis x of the eccentric insert is fixed at the position shown in the figure, the eccentric insert 101 is centered on the center axis 112 of the eccentric insert 101. The second optical axis intersection portion 113 of the second molding surface 43 formed on the eccentric nest 101 can move along a circular locus 122.

Further, the second optical axis intersection portion 113 can be moved to any position within the circular predetermined range 123.
FIG. 10 shows a locus 122 of the second optical axis intersection portion 113 when the central axis 112 of the eccentric nest 101 is moved stepwise by 45 degrees by rotating the support cylinder 102 fixed in FIG. It is. Actually, the angle of the support tube 102 can be continuously changed in a stepless manner, so the second optical axis intersection portion 113 can be moved to any of the points within the predetermined range 123 described above. That is, the second optical axis intersection portion 113 of the molding surface formed in the fixed-side eccentric nest 101 of the present embodiment can be disposed anywhere within the predetermined range 123 by the rotation of the support cylinder 102 and the eccentric nest 101. Therefore, as long as the first optical axis intersection part 140 (outer diameter center part 141) of the movable molding surface is within the predetermined range 123, the first optical axis intersection part 140 (outer diameter center part 141) and the second It is possible to match the optical axis intersection points 113.
The distance between the center axis 112 of the eccentric insert 101 and the center axis 111 of the support cylinder 102 is R2, and the distance between the center axis 112 of the eccentric insert 101 and the second optical axis intersection portion 113 is R1. In this embodiment, R1 = R2 in the present embodiment, and the center position in FIG. If R1 <R2, a region that cannot be covered in the central portion of FIG. 10, that is, a region where the second optical axis intersection portion 113 cannot be arranged is generated in the central portion, which is not preferable. Therefore, it is preferable that R1 ≧ R2. In the case of R1> R2, an overlapping range is generated in the central portion of FIG. 10, the diameter of the circle of the predetermined range 123 is reduced, and the area where the second optical axis intersection portion 113 can be disposed is generally small. Become. Within the second optical axis intersection, that is, within the circular movement range where the radius is R2-R1, the combination of the angle of the eccentric nest 101 and the angle of the support cylinder 102 at which the position of the second optical axis intersection portion 113 is the same is 2. Each one exists and becomes an inefficient setting.

FIG. 11 is a schematic view of a selling camera 205 having a lens unit 202 in which a plurality of resin lenses 10a to 10d are supported in a lens barrel 201 and an image sensor 203 arranged on the side connecting the images of the lens unit 202. It is. The resin lenses 10a to 10d are different in shape from the resin lens 10, but the positions of the first optical axis intersection point 17 and the second optical axis intersection point 18 are aligned with the center of the outer diameter as described above. In this mold apparatus, molds having different molding surfaces are used and molded by the injection molding method of the present embodiment. These resin lenses 10a to 10d are press-fitted into the lens barrel 201. Since the deviation of the first optical axis intersection point 17 and the second optical axis intersection point 18 from the center of the outer diameter of the resin lenses 10a to 10d is small as in the resin lens 10 described above, the resin lenses 10a to 10d are connected to the lens. Even if it is press-fitted and arranged in the lens barrel 201 without worrying about the directionality, the deviation of each optical axis of the resin lenses 10a to 10d can satisfy the deviation within 2μ, which is the required accuracy, and the resolution of the lens unit 202 can be reduced. It is possible to increase the resolution, and the resolution can be increased in shooting with the camera 205 using the lens unit 202. Therefore, it is possible to effectively use the image sensor 203 having a high pixel. In addition, it is also possible to further increase the accuracy by rotating and pressingly arranging the lenses in advance so that the deviation directions of the optical axes of the resin lenses 10a to 10d coincide.
Although all the lens units in the form of FIG. 11 are made of resin lenses, some of them may be glass lenses.

  FIG. 13 is a schematic view of an injection molding apparatus. The injection molding apparatus includes a mold device, a mold opening / closing unit 301, a molten resin supply unit 302, and the like. As described above, the mold apparatus includes the fixed mold 31 and the movable mold 32. The mold opening / closing unit 301 is a part that opens and closes the fixed mold 31 and the movable mold 32, and includes a movable platen, a fixed platen, a tie bar, and the like. The molten resin supply unit 302 is a part that supplies the molten resin to a cavity partitioned by the first optical functional surface molding unit 142, the second optical functional surface molding unit 131, and the outer peripheral molding unit 150, and includes a nozzle, a hand heater Equipped with cylinders.

DESCRIPTION OF SYMBOLS 10 Resin lens 10a-d Resin lens 11 1st surface 12 2nd surface 13 1st optical functional surface 14 2nd optical functional surface 17 1st optical axis intersection 18 Second optical axis intersection 19 Outer peripheral surface 21 Projection 31 Fixed mold (The other mold)
32 Movable mold (one mold)
43 Second molding surface 57 First molding surface 101 Eccentric insert 102 Support cylinder 103 Insert 111 Center axis (rotation axis) of support cylinder
112 Eccentric nesting center axis (rotating axis)
113 Second optical axis intersection part 131 Second optical function surface molding part 140 First optical axis intersection part 141 Outer diameter center part (center axis of nesting, rotation axis)
142 First optical function surface molding unit 150 Outer periphery molding unit 202 Lens unit 205 Camera 301 Mold opening / closing unit 302 Molten resin supply unit R1 Distance R2 between the center axis of the eccentric nest and the center axis of the support cylinder R2 Distance between the central axis and the second optical axis intersection of the eccentric nest

Claims (11)

A pair of molds for molding a resin lens having two optical function surfaces, wherein one of the molds is one of the two optical function surfaces inside the outermost periphery of the resin lens; A first optical functional surface molding portion that molds one of the optical functional surfaces, and the other mold includes a second optical functional surface molding portion that molds the other optical functional surface of the resin lens,
An outer peripheral molding part for determining the outer diameter of the resin lens by molding the outermost peripheral part of the outer side of the optical functional surface of the resin lens on one of the molds is provided,
The center of the outer diameter of the resin lens determined by the first optical axis intersection part of the first optical functional surface molding part that molds the optical axis intersection of one of the optical functional surfaces of the resin lens and the outer peripheral molding part The first optical functional surface molding part for molding the outer diameter center portion of the first optical functional surface molding part is arranged overlapping,
The other mold has a substantially cylindrical eccentric insert with the second optical functional surface molding portion provided on the front end surface thereof, and the eccentric insert is supported rotatably about the central axis of the eccentric insert. And a support cylinder
The eccentric nesting is such that the second optical axis intersection portion of the second optical functional surface molding portion that molds the optical axis intersection of the other optical functional surface of the resin lens is relative to the central axis of the eccentric nesting. Provided eccentrically,
The support cylinder is supported by one of the molds so as to be rotatable around a central axis of the support cylinder,
The mold apparatus according to claim 1, wherein a central axis of the eccentric telescope is eccentric with respect to a central axis of the support cylinder.   The one mold is provided with a substantially columnar insert having the first optical functional surface molding portion provided on the front end surface thereof so as to be rotatable around the center axis of the insert, and the center axis of the insert The mold apparatus according to claim 1, wherein the first optical axis intersection portion of the first optical function surface molding portion is provided on the mold optical device. The molding surface for molding the resin lens of the other mold has an opening for exposing the tip surface of the eccentric nest,
The eccentric insertion based on the rotation around the central axis of the support cylinder that is eccentric with respect to the central axis of the eccentric insert between the inner peripheral edge of the opening and the outer peripheral edge of the tip end surface of the eccentric insert. The mold apparatus according to claim 1, wherein a gap that allows the child to shake is provided.   The distance between the central axis of the eccentric insert and the central axis of the support cylinder is equal to or less than the distance between the central axis of the eccentric insert and the second optical axis intersection part of the eccentric insert. The mold apparatus according to claim 1, wherein the mold apparatus is formed. A mold apparatus according to any one of claims 1 to 4, a mold opening / closing part that opens and closes the one mold and the other mold,
An injection molding apparatus comprising: a molten resin supply unit configured to supply a molten resin to a cavity partitioned by the first optical functional surface molding unit, the second optical functional surface molding unit, and the outer peripheral molding unit. An injection molding method for molding a resin lens using the mold apparatus according to any one of claims 1 to 4,
After assembling the injection molding apparatus including the pair of molds, the second optical axis intersection part of the second optical functional surface molding part is located at the first optical axis intersection part of the first optical functional surface molding part. Injection molding, wherein the support cylinder is rotated about the central axis with respect to the other mold so as to overlap, and the eccentric nest is rotated about the central axis with respect to the support cylinder Method. A resin lens having a first surface and a second surface, each having an optical functional surface,
The optical axis intersection of each of the two optical functional surfaces is disposed at a position of 2 μm or less from the center of the outer diameter,
On one surface of the first surface and the second surface, a substantially annular and parting line-shaped ridge is provided inside the outer peripheral surface,
The resin protrusion is characterized in that the total width of the protrusions facing each other across the optical axis intersection is constant at an arbitrary position.   8. The resin lens according to claim 7, wherein the optical functional surfaces of the first surface and the second surface are aspherical surfaces. A method for producing a resin lens according to claim 7 or 8,
A method for producing a resin lens, comprising producing the resin lens using the mold apparatus according to claim 1. It has a first surface and a second surface, and each of these surfaces has an optical function surface provided with an optical axis intersection, and the optical axis intersection of each of the two optical function surfaces is disposed at a position of 2 μm or less from the center of the outer diameter. As described above, one of the first surface and the second surface has a substantially annular and parting line shape outside the optical function surface and inside the outer peripheral surface, and sandwiching the optical axis intersection A plurality of resin lenses having a ridge whose total width of two opposing positions is constant at an arbitrary position,
Since the plurality of resin lenses are respectively press-fitted into the lens barrel and positioned, all the optical axis intersections of the plurality of resin lenses are disposed at a position of 2 μm or less from the center line of the lens barrel. Characteristic lens unit.   A camera comprising the lens unit according to claim 10, wherein an image sensor is provided on a side connecting images of the lens unit.

Images