WO2014050602A1

WO2014050602A1 - Lens and molding die

Info

Publication number: WO2014050602A1
Application number: PCT/JP2013/074742
Authority: WO
Inventors: 下間剛
Original assignee: コニカミノルタ株式会社
Priority date: 2012-09-29
Filing date: 2013-09-12
Publication date: 2014-04-03

Abstract

Provided is a lens capable of improving the efficiency of taking light from a light source and increasing the degree of freedom in the size of the disposed light source. A plurality of leg parts (10d) are arranged outside a circle with a diameter of 0.37 D (D is the diameter of a lens (10)) with the optical axis (OA) as the center, thus preventing the obstruction of a light beam (LB1) from a light emitting element (50) by the leg parts (10d). As a result, the utilization efficiency of light may be improved. Further, by arranging the plurality of leg parts (10d) in the area outside the circle of 0.37 D, it is possible to increase the degree of freedom in size of the light emitting element (50) arranged between the plurality of leg parts (10d) opposite a first optical surface (S1). Further, it is possible to distance the plurality of leg parts (10d) from the light emitting element (50) to some extent, to prevent localized heating inward of the leg parts (10d), and to minimize the formation of cracks in the periphery of the leg parts (10d).

Description

Lens and mold

The present invention relates to a lens for controlling a luminous flux from an LED or the like and a molding die for manufacturing the lens.

The lens used for controlling the illumination light beam is also called a light beam control member, and has a special optical surface and is disposed so as to cover the light source. Such a lens includes a first optical surface having a deep concave shape and a small diameter, and a second optical surface having a convex shape as a whole and having a relatively small curvature, and is a flat surface provided around the first optical surface. Three leg portions are formed so as to protrude from the bottom portion in an even arrangement (see Patent Document 1).

Since the bottom surface provided on the lens also serves as a reflecting surface for effective use of light, the three legs have a peak light amount when the reflected light from the second optical surface is incident on the flat surface. It is arranged inside the circumferential region. By arranging the legs in this way, the influence on the optical characteristics can be suppressed to a small extent, and not only the lens mounting area on the support substrate can be reduced, but also cracks in the legs due to the difference in thermal expansion. It can also be prevented.

However, if the lens leg is placed in the vicinity of the LED, the light beam from the LED is directly incident on the leg, and then the optical characteristics of the entire lens are unexpected due to reflection and transmission. End up. This is a serious problem particularly in lenses for backlight illumination that are desired to have a uniform light distribution. In addition, the LED is arranged further inside the leg portion arranged on the inner side, which restricts the size of the LED. In addition, in order to achieve even more brightness and a wide range and uniform light distribution, the LED may be high-powered, and if the leg portion is disposed in the vicinity of the LED, the light is incident from the LED. Not only changes in optical characteristics, but also distortion and cracks of the leg due to heat from the LED occur.

JP 2012-4078 A

The present invention has been made in view of the above-described background art, and the light distribution is not uniform due to light directly incident on the leg portion from the light source, and is arranged while suppressing distortion or cracking of the leg portion. An object of the present invention is to provide a lens having a high degree of freedom in the size of the light source and a molding die for manufacturing the lens.

In order to achieve the above object, a lens according to the present invention is a lens that controls the traveling direction of a light beam emitted from a light emitting element, and includes a first optical surface and a second diameter that is larger than the first optical surface. An optical surface, a flat surface provided around the first optical surface and extending substantially perpendicular to the optical axis, and a plurality of legs formed so as to protrude from the flat surface. When the lens diameter is D, the lens is arranged outside a circle having a diameter of 0.37D with respect to the optical axis. Here, that the leg is outside the circle having a diameter of 0.37D means that the portion of the leg that is closest to the optical axis is outside the circle having a diameter of 0.37D.

In the above lens, since the plurality of legs are arranged outside the circle having a diameter of 0.37D with respect to the optical axis, the legs can be arranged sufficiently away from the optical axis. Thereby, it can suppress that the light ray radiate | emitted from the light emitting element enters into a leg part, and can prevent that the optical characteristic of a lens deteriorates by the unexpected light ray. In the said lens, it can suppress that the light ray from a light emitting element is prevented by a leg part, and can improve the utilization efficiency of light. In addition, by arranging the plurality of leg portions in the above range, the degree of freedom of the size of the light emitting element disposed between the plurality of leg portions facing the first optical surface can be increased. Further, since the plurality of legs can be separated from the light emitting element to some extent, local heating inside the legs can be suppressed, and formation of cracks or distortion around the legs can be suppressed. Furthermore, since the position of the leg portion is not too much inside the lens, it is easy to attach the lens to the substrate with the leg portion as a contact point.

In a specific aspect of the present invention, in the lens, the plurality of leg portions are arranged inside a circle having a diameter of 0.8D with respect to the optical axis. In this case, the leg portion exists in the inner region from the diameter 0.8D where the light reflected by the second optical surface is relatively small, and the influence of the light reflected by the leg portion on the light distribution characteristics is extremely small. Can be kept to a small amount. Further, the leg portion does not approach the lens periphery too much, the substrate to which the lens is attached can be made small, and cracks due to the difference in thermal expansion coefficient are less likely to occur.

In another aspect of the present invention, the plurality of leg portions are arranged in a range from 0.5D to 0.7D in diameter with respect to the optical axis. In this case, by setting the diameter to 0.5D or more, the influence on the optical characteristics due to the presence of the leg portion can be further reduced, and the degree of freedom of the size of the light emitting element can be further increased. On the other hand, by setting the diameter to 0.7D or less, it is possible to further reduce the influence on the light distribution characteristics while ensuring a sufficient space for arranging the legs. Further, the peripheral portion of the flat surface also has a function as a reflecting surface, and it is desirable that the leg portion be separated to some extent from the outer edge of the flat surface.

In yet another aspect of the present invention, the plurality of legs have traces of protruding pins for release on the bottom surface. In this case, it is possible to prevent a pin mark from remaining on the flat surface of the lens. Since there are no traces of pins protruding on a flat surface or the like, it is possible to prevent light reflected by the second optical surface from protruding and becoming unexpected stray light on the pin traces, and to prevent deterioration of the optical performance of the lens. it can. In addition, it is possible to suppress the deformation of the lens as much as possible when the lens is protruded after molding, and from this viewpoint, it is possible to suppress the deterioration of the optical performance of the lens. In particular, it is preferable that the leg portion is 0.37D or more and 0.8D or less because distortion of the lens due to protrusion is small.

In yet another aspect of the present invention, the plurality of leg portions are arranged at equal intervals on a circumference centered on the optical axis. In this case, the lens can be supported on the support substrate with a good balance.

In yet another aspect of the present invention, the plurality of leg portions have a circular shape or an elliptical outline having a long axis in the radial direction centered on the optical axis when projected onto a plane perpendicular to the optical axis. In particular, in the case of an ellipse, the support range can be expanded compared to the area thereof, so that the stability of the support can be ensured while preventing the deterioration of the optical characteristics of the lens. In other words, in the case of an ellipse, the area is smaller than a circle whose diameter is the major axis of the ellipse, so that the influence on the optical characteristics is small, and it is possible to stably adhere to a wide substrate or a narrow substrate. it can.

In yet another aspect of the present invention, the plurality of legs have a roughened surface. In this case, since light diffuses on the surface of the leg portion, stray light generated by light that is directly or indirectly incident on the leg portion can be suppressed.

In still another aspect of the present invention, the first optical surface has a concave shape having a relatively large curvature compared to the second optical surface, and the second optical surface has a convex shape as a whole and is locally located in the center. It has a typical concave area.

In yet another aspect of the present invention, the lens is for LED backlight illumination. In this case, the LEDs enable uniform and efficient illumination on the liquid crystal panel and other display elements.

In order to achieve the above object, a molding die according to the present invention is a molding die having a transfer surface for injection molding a lens for controlling the traveling direction of a light beam emitted from a light emitting element. A first optical surface, a second optical surface having a larger diameter than the first optical surface, a flat surface provided around the first optical surface and extending substantially perpendicular to the optical axis, and protruding from the flat surface The plurality of legs are arranged outside the circle having a diameter of 0.37D with respect to the optical axis, where D is the lens diameter. That is, the molding die forms a transfer surface for forming the first optical surface, a transfer surface for forming the second optical surface, a transfer surface for forming a flat surface, and a plurality of legs. And a plurality of leg portions provided on the lens by the leg transfer surface are arranged as described above.

In the molding die, the first optical surface, the second optical surface, the flat surface, and the transfer surfaces for the plurality of legs are arranged outside the circle having a diameter of 0.37D with respect to the optical axis. In the obtained lens, the light beam from the light emitting element can be prevented from being obstructed by the leg portion, and the light utilization efficiency can be increased. In addition, by arranging the plurality of leg portions in the above range, the degree of freedom of the size of the light emitting element disposed between the plurality of leg portions facing the first optical surface can be increased. Further, since the plurality of legs can be separated from the light emitting element to some extent, local heating inside the legs can be suppressed, and cracks can be prevented from being formed around the legs.

In a specific aspect of the present invention, in the molding die, the plurality of leg portions are arranged inside a circle having a diameter of 0.8D with respect to the optical axis.

In another aspect of the present invention, the plurality of leg portions are arranged in a range from 0.5D to 0.7D in diameter with respect to the optical axis.

In another aspect of the present invention, a release pin for release is provided at a portion where the bottom surface of the plurality of leg portions is transferred.

In still another aspect of the present invention, the first mold includes a first mold that molds the first optical surface side of the lens and a second mold that molds the second optical surface side of the lens. Has a core part for forming the first optical surface by transfer, and a peripheral part arranged around the core part to form a flat surface and a plurality of legs. In this case, in the peripheral portion, the portion that transfers from the portion corresponding to the leg portion to the portion adjacent to the core portion does not become too thin, so that the mold processing becomes easy.

1A is a rear view of the lens of the first embodiment, FIG. 1B is a cross-sectional view taken along arrow AA in FIG. 1A, and FIG. 1C is a front view of the lens in FIG. 1A. 2A and 2B are diagrams illustrating the lens shape and functions shown in FIG. 1A and the like. 3A is an enlarged cross-sectional view of a molding die for molding the lens of FIG. 1, and FIG. 3B is an end view of a movable die in the die of FIG. 3A. It is a reverse view of the lens of 2nd Embodiment.

[First Embodiment]
A lens and a mold according to a first embodiment of the present invention will be described with reference to the drawings.

A lens 10 shown in FIGS. 1A to 1C is a lens (light flux controlling member) that controls a light beam for illumination from an LED (Light Emitting Diode) or the like, that is, a traveling direction of a light flux emitted from a light emitting element. That is, the lens 10 is an illumination optical system for LED backlight illumination, for example, and constitutes a part of the backlight light source. As shown in FIGS. 1A to 1C, the lens 10 includes an optical part 10a, an outer peripheral part 10b, a protruding part 10c, and a leg part 10d.

The optical part 10a is a part having an optical function, and has a pair of opposed first and second optical surfaces S1 and S2 and a flat surface S6 extending from the periphery of the first optical surface S1. The first optical surface S1 has a concave shape, and the second optical surface S2 has an overall convex shape. Here, the first optical surface S1 has a concave shape having a relatively larger curvature than the second optical surface S2, and is deeply recessed toward the center of the second optical surface S2. The second optical surface S2 has a shallow concave region at the center, and has a larger diameter than the first optical surface S1. As a result, the center of the optical unit 10a is thin, and the periphery of the center is thick. That is, the lens 10 is a lens having a high thickness deviation ratio. The flat surface S6 extends substantially perpendicular to the optical axis OA and is on the same plane as the first outer peripheral surface S3 of the outer peripheral portion 10b. A light-emitting element such as an LED, which will be described later, is disposed so as to face the first optical surface S1 side.

The outer peripheral part 10b extends around the optical part 10a. The outer peripheral part 10b has a pair of opposing first and second outer peripheral surfaces S3 and S4, and an outer peripheral side surface S5 connecting the first and second outer peripheral surfaces S3 and S4. The first and second outer peripheral surfaces S3 and S4 extend perpendicular to the optical axis OA of the lens 10.

The protrusion 10c protrudes from the outer peripheral side surface S5 of the outer peripheral portion 10b in the outer peripheral direction. The protruding portion 10c is provided so as to extend to the outside of the outer peripheral portion 10b. The protrusion 10c is a flat portion, and specifically, has a rectangular plate shape or block shape. The protrusion 10c has a pair of first and second protrusion surfaces S7 and S8 perpendicular to the optical axis OA, and a protrusion side surface S10 sandwiched between the first and second protrusion surfaces S7 and S8. . A gate cut trace GS is formed on the second projection surface S8 on the second optical surface S2 side of the first and second projection surfaces S7 and S8. The gate cut trace GS is formed in the depression 10g and is not protruding from the second protrusion surface S8. The protruding side surface S10 of the protruding portion 10c is connected to the outer peripheral side surface S5 of the outer peripheral portion 10b at both ends.

The leg part 10d is a part attached to the support substrate 60 (refer FIG. 2B) of a light emitting element. The leg portion 10d is a thin cylindrical or low trapezoidal portion, and protrudes in a direction parallel to the optical axis OA from the flat surface S6 of the optical portion 10a. In the case of the present embodiment, the leg portions 10d are provided at three locations at equal intervals on the same circumference around the optical axis OA of the flat surface S6. Each leg 10d has a side wall S21 and a top surface S22. The top surface S22 is parallel to the surrounding flat surface S6. In addition, the trace 71 of the protrusion pin 31 mentioned later is formed in the top | upper surface S22 of the leg part 10d. The side wall S21 and the top surface S22 of the leg 10d can be roughened. In this case, stray light can be prevented from being generated by the light LB3 (see FIG. 2B) that is directly or indirectly incident on the leg 10d. The roughening of the leg 10d can be achieved by roughening the transfer surface of the mold, which will be described later, but it can also be roughened in a later step.

Referring to FIGS. 2A and 2B, the shape feature of the lens 10 shown in FIG. 1A and the like will be described. As shown in FIG. 2A, the three leg portions 10d are disposed outside an inner non-arrangement region AC that is a circular region centered on the optical axis OA. The diameter AR of the inner non-arrangement region AC is 0.37 D, where D is the diameter of the lens 10. That is, the three leg portions 10d are arranged outside including the circumference of a circle having a diameter of 0.37D with respect to the optical axis OA. The leg portion 10d may be formed outside the inner non-arrangement area AC, but is preferably formed inside the outer non-arrangement area AC2 (on the optical axis OA side). The diameter AR2 of the outer non-arrangement region AC2 (the inner diameter of the non-arrangement region AC2) is 0.8D, where D is the diameter of the lens 10. That is, the leg portion 10d is in a region having a diameter of 0.37D to 0.8D centered on the optical axis OA, and more preferably in a region having a diameter of 0.5D to 0.7D. More preferably, the leg 10d is in the region of 0.55D to 0.65D. Note that the leg 10d is in the region having a diameter of 0.37D to 0.8D means that the point closest to the optical axis OA of the leg 10d is outside the circle having a diameter of 0.37D and the leg 10d It means that the point farthest from the optical axis OA is inside the circle having a diameter of 0.8D. The non-arrangement regions AC and AC2 do not include the circumferences of 0.37D and 0.8D, that is, on the boundary line, and the leg portions 10d can be disposed on the boundary line.

As shown in FIG. 2B, the light beam LB2 emitted from the light emitting element 50 enters the lens 10 from the first optical surface S1 side, passes through the second optical surface S2 as it is, and becomes illumination light. Further, the light beam LB2 partially reflected by the second optical surface S2 is partially reflected again by the flat surface S6, and then passes through the second optical surface S2, thereby contributing as illumination light. Note that the illumination light such as the light beam LB2 emitted from the light emitting element 50 and whose luminous flux is controlled by the lens 10 is used as a backlight for illuminating a liquid crystal panel and other display elements.

In the present embodiment, by arranging the three leg portions 10d outside the non-arrangement region AC as described above, these leg portions 10d can be sufficiently separated from the optical axis OA and the light emitting element 50. Thereby, it can suppress that the light ray LB1 inject | emitted from the light emitting element 50 injects into the leg part 10d, Such an unexpected light ray LB1 becomes stray light, and the light distribution characteristic (optical performance) of the lens 10 deteriorates. Can be prevented. In addition, by arranging the three leg portions 10d outside the non-arrangement region AC as described above, the size of the light emitting element 50 can be increased, and the degree of freedom of the size of the light emitting element 50 can be increased. Furthermore, by arranging the three leg portions 10d outside the non-arrangement region AC as described above, the three leg portions 10d are sufficiently separated from the light emitting element 50, and local heating inside the leg portion 10d is performed. It is possible to suppress the formation of cracks in the base portion 10j of the leg portion 10d and the like, and the occurrence of changes in optical performance due to distortion caused by local heating. As described above, by arranging the leg portion 10d outside the non-arrangement area AC, it is possible to obtain a highly reliable lens while making the light distribution characteristics of the lens uniform.

By arranging the three leg portions 10d inside the non-arrangement region AC2 as described above (on the optical axis OA side), these leg portions 10d pass the light beam LB2 reflected by the second optical surface S2. Is present in a relatively small inner region, and the influence on the light distribution characteristics by the light reflected by the leg 10d can be suppressed to a very small amount. Further, the leg portion 10d does not come too close to the peripheral portion of the lens 10, the support substrate 60 to which the lens 10 is attached can be made small, and cracks due to the difference in thermal expansion coefficient are less likely to occur.

The light emitting element 50 and the lens 10 are aligned with each other and fixed on the support substrate 60. At this time, the end surface (top surface S22) of the leg 10d is bonded to the support substrate 60, and the arrangement of the lens 10 with respect to the support substrate 60 is adjusted.

As shown in FIG. 3A, a molding die 100 for manufacturing the lens 10 shown in FIG. 1A and the like includes a fixed die 11, a movable die 12, a pinpoint gate mechanism 40, and an ejecting mechanism 30. .

The movable mold 12 is supported by a movable plate (not shown) as a first mold and can move forward and backward with respect to the fixed mold 11. The movable mold 12 includes a core portion 12i disposed around the axis AX, and a peripheral portion 12j disposed around or outside the core portion 12i. The movable mold 12 has a first optical surface transfer surface T1, a first outer peripheral surface transfer surface T3, an outer peripheral side surface transfer surface T5, and a flat surface transfer surface T6 on the mold matching surface PP side facing the fixed mold 11. The first protrusion transfer surface T7, the protrusion side transfer surface T10, and the leg transfer surfaces T21 and T22. These transfer surfaces T1, T3, T5, T6, T7, T10, T21, and T22 become the first transfer surface 12a that forms the first optical surface S1 side of the lens 10. Among these, the first optical surface transfer surface T1 is provided on the surface of the core portion 12i. The other transfer surfaces T3, T5, T6, T7, T10, T21, and T22 are provided on the surface of the peripheral portion 12j. The first optical surface transfer surface T1 corresponds to the shape of the first optical surface S1 of the lens 10 and has a shape obtained by inverting this. That is, the first optical surface transfer surface T1 has a convex shape. The first outer peripheral surface transfer surface T3 corresponds to the shape of the first outer peripheral surface S3 of the lens 10. The outer peripheral side transfer surface T5 corresponds to the shape of the outer peripheral side surface S5 of the lens 10. The flat surface transfer surface T6 corresponds to the shape of the flat surface S6 of the lens 10. The first protrusion transfer surface T7 corresponds to the shape of the first protrusion surface S7 of the lens 10. The protrusion side transfer surface T10 corresponds to the shape of the protrusion side surface S10 of the lens 10. The leg transfer surfaces T21 and T22 correspond to the shape of the leg 10d of the lens 10. Here, the leg transfer surface T21 corresponds to the side wall S21 of the leg 10d and has a shape obtained by inverting it. The leg transfer surface T22 corresponds to the top surface S22 of the leg 10d and has a shape obtained by inverting it. A central portion of the leg transfer surface T22 is a tip surface 31a of a protrusion pin 31 described later. In addition, the movable mold 12 is provided with a cooling path (not shown). This cooling path is for flowing cooling water or the like, and is provided for preventing overheating of the movable mold (first mold) 12 and cooling the molten resin.

In the above, the movable mold 12 includes the core portion 12i for forming the first optical surface S1 by transfer, and the peripheral portion 12j disposed around the core portion 12i to form the flat surface S6 and the plurality of leg portions 10d. And have. In this case, in the peripheral portion 12j, the portion that transfers from the protruding pin 31 or the like corresponding to the leg portion 10d to the portion adjacent to the core portion 12i does not become too thin, so that the mold processing becomes easy.

The fixed mold 11 is supported and fixed by a fixed plate (not shown) as a second mold. The fixed mold 11 has a second optical surface transfer surface T2, a second outer peripheral surface transfer surface T4, and a second protrusion transfer surface T8 on the mold matching surface PP side facing the movable mold 12. These transfer surfaces T2, T4, and T8 serve as a second transfer surface 11a that forms the second optical surface S2 side of the lens 10. The second optical surface transfer surface T2 corresponds to the shape of the second optical surface S2 of the lens 10 and has a shape obtained by inverting this. That is, the second optical surface transfer surface T2 has a concave shape as a whole. The second outer peripheral surface transfer surface T4 corresponds to the shape of the second outer peripheral surface S4 of the lens 10. The second protrusion transfer surface T8 corresponds to the shape of the second protrusion surface S8 of the lens 10. A mold space (cavity) CV is formed between the fixed mold 11 and the movable mold 12 by clamping. A gate 41 of a pinpoint gate mechanism 40, which will be described later, communicates with the cavity CV via the second protrusion transfer surface T8. The cavity CV corresponds to the outer shape of the lens 10 shown in FIGS. 1A to 1C and the like. In other words, the cavity CV is a space with a high thickness deviation ratio that is thin at the center and has a large thickness difference between the center and the periphery thereof. In addition, the fixed mold 11 is provided with a cooling path (not shown). This cooling path is for flowing cooling water or the like, and is provided to prevent overheating of the fixed mold (second mold) 11 and to cool the molten resin.

Although not shown, the movable mold 12 has a plurality of first transfer surfaces 12a. The fixed mold 11 also has a plurality of second transfer surfaces 11a facing the plurality of second transfer surfaces 12a.

With reference to FIG. 3B etc., the shape characteristic of the molding die 100 shown to FIG. 3A is demonstrated. In the movable mold 12, the three leg transfer surfaces T22 correspond to the leg 10d shown in FIG. 1A and the like. The leg transfer surface T22 is disposed outside the inner non-arrangement region AC that is a circular region centered on the axis AX. The diameter AR of the inner non-arrangement region AC is 0.37D, where D is the diameter of the cavity CV corresponding to the diameter of the lens 10. In the illustrated embodiment, the leg transfer surface T22 is formed on the inner side (axis AX side) of the outer non-arrangement region AC2 larger than the diameter 0.8D. That is, like the leg portion 10d, the leg transfer surface T22 is in a region having a diameter of 0.37D to 0.8D centered on the axis AX, and more preferably in a region having a diameter of 0.5D to 0.7D. It is in. More preferably, the leg transfer surface T22 is in the region of 0.55D to 0.65D.

The pinpoint gate mechanism 40 shown in FIG. 3A has a structure that automatically performs gate cutting by mold opening. In other words, in addition to the fixed mold 11 and the movable mold 12, the molding mold 100 is provided with a runner removal mold (not shown) on the fixed mold 11 side. The runner removal mold is closed to the fixed mold 11 side during molding and separated from the fixed mold 11 during mold release.

The pinpoint gate mechanism 40 has a gate 41 that tapers toward the cavity CV on the die matching surface PP side. The tip 41a of the gate 41 is arranged in a state of protruding from the mold matching surface PP toward the movable mold 12 side.

The ejecting mechanism 30 is urged by a drive device (not shown) and can be advanced and retracted at a desired timing along the AB direction along the axis AX of the molding die 100. As shown in FIG. 3B, the protrusion mechanism 30 includes a plurality of protrusion pins 31. Each protruding pin 31 is inserted into a pin hole 12 d (see FIG. 3A) provided in the movable mold 12. Three pin holes 12d are provided in correspondence with the leg transfer surface T22. As already described, the tip of the protrusion pin 31 is the central portion of the leg transfer surface T22 that faces the cavity CV in the illustrated state where the fixed mold 11 and the movable mold 12 are clamped.

Hereinafter, a method for manufacturing the lens 10 will be described. First, the fixed mold 11 and the movable mold 12 which are separated from each other are adjusted to a predetermined temperature in the standby state. Next, the movable mold 12 is operated to close the fixed mold 11 and the movable mold 12, and the

molds

11 and 12 are clamped with a predetermined pressure. At this time, a cavity CV is formed between the

molds

11 and 12. Next, the molten resin guided to the gate 41 of the pinpoint gate mechanism 40 in a state where the

molds

11 and 12 are clamped is injected into the cavity CV from the opening of the tip 41a. Next, the molten resin in the cavity CV is cooled by both

molds

11 and 12, and the lens 10 as a molded product is obtained. In this state, when the mold opening for separating the movable mold 12 from the fixed mold 11 is performed, the lens 10 is separated from the fixed mold 11 and is attached to the movable mold 12. Next, when the protrusion mechanism 30 is advanced to cause the protrusion pin 31 to protrude, the lens 10 is peeled off from the movable mold 12 and the release of the lens 10 is completed.

In addition, when the

molds

11 and 12 are opened, the runner removal mold (not shown) of the pinpoint gate mechanism 40 is separated from the fixed mold 11. Thereby, unnecessary parts (not shown) such as a gate part and a runner part other than the lens 10 are pulled out from the fixed mold 11. That is, the lens 10 is released by opening the fixed mold 11 and the movable mold 12, and the gate is automatically cut.

In the lens 10 of the first embodiment, since the plurality of leg portions 10d are arranged outside the circle having a diameter of 0.37D (D is the diameter of the lens 10) with respect to the optical axis OA, It can arrange | position enough away from the axis | shaft OA, can suppress that the light ray LB1 from the light emitting element 50 is prevented by the leg part 10d, and can improve the utilization efficiency of light. In addition, by arranging the plurality of leg portions 10d in the range outside the circle of 0.37D, the size of the light emitting element 50 arranged between the plurality of leg portions 10d facing the first optical surface S1. The degree of freedom can be increased. In addition, the plurality of legs 10d can be separated from the light emitting element 50 to some extent, local heating inside the legs 10d can be suppressed, and cracks and the like can be prevented from being formed around the legs 10d. .

In the molding die (die) 100 of the first embodiment, the pinpoint gate mechanism 40 can be replaced with a hot runner mechanism or the like.

[Second Embodiment]
Hereinafter, the lens and the mold according to the second embodiment will be described. The lens and the molding die of the second embodiment are partially modified from the lens and the molding die of the first embodiment, and items not specifically described are the same as those of the lens and the molding die of the first embodiment. It is.

As shown in FIG. 4, in this embodiment, the contours transferred to the surfaces perpendicular to the optical axis OA of each leg 2010d provided on the lens 10 are elliptical, and the major axis extends in the radial direction. Yes. In this case, the lens 10 can be securely fixed in correspondence with both the support substrate 60A having a narrow width and the support substrate 60B having a wide width indicated by the imaginary line. Here, it is conceivable that the legs 2010d are not elliptical but circular, but if the legs are simply circular, the area of the legs increases and the area of the flat surface S6 decreases, and the use of light rays. As the efficiency decreases, the optical characteristics deteriorate. By adopting an elliptical shape extending in the radial direction like the leg portion 2010d provided on the lens 10 of the present embodiment, it is possible to prevent deterioration of optical characteristics while supporting

various support substrates

60A and 60B.

As mentioned above, although this invention was demonstrated according to embodiment, this invention is not limited to the said embodiment. For example, in the above embodiment, the optical part 10a and the outer peripheral part 10b of the lens 10 have a circular outline, but the optical part 10a and the outer peripheral part 10b may have a rectangular or oval (including elliptical) outline. .

In the above-described embodiment, the circular leg portion 10d and the elliptical leg portion 2010d have been described. However, the contour shape of the leg portion can be changed as appropriate according to the application, and the like, such as a triangle, a rectangle, an ellipse (including an ellipse) It can be set as various shapes. The light emitting element 50 is not limited to an LED, and may be an LD (LaserLaDiode), a VCSEL (Vertical Cavity Surface Emitting Laser), or the like.

In the above embodiment, the molding die 100 is used as a horizontal die or a saddle die. In the case of the horizontal type, the fixed mold 11 and the movable mold 12 are arranged to face each other in the horizontal direction. In the case of the vertical type, the fixed mold 11 and the movable mold 12 are arranged to face each other in the vertical direction.

In the above embodiment, the fixed mold 11 and the movable mold 12 can be replaced. That is, the first optical surface S1 and the like can be formed on the fixed mold 11 side, and the second optical surface S2 and the like can be formed on the movable mold 12 side.

Claims

A lens for controlling the traveling direction of light emitted from the light emitting element,
A first optical surface;
A second optical surface having a larger diameter than the first optical surface;
A flat surface provided around the first optical surface and extending substantially perpendicular to the optical axis;
A plurality of legs formed so as to protrude from the flat surface;
The plurality of legs are lenses arranged outside a circle having a diameter of 0.37D with respect to the optical axis, where D is a lens diameter.
The lens according to claim 1, wherein the plurality of leg portions are arranged inside a circle having a diameter of 0.8D with respect to the optical axis.
The lens according to claim 1 or 2, wherein the plurality of leg portions are disposed within a range of a diameter of 0.5D to 0.7D with respect to the optical axis.
The lens according to any one of claims 1 to 3, wherein the plurality of legs have traces of a release pin for release on a bottom surface.
The lens according to any one of claims 1 to 4, wherein the plurality of leg portions are arranged at equal intervals on a circumference centered on the optical axis.
6. The plurality of legs according to claim 1, wherein when projected onto a plane perpendicular to the optical axis, the plurality of legs have a circular shape or an elliptical outline having a major axis in a radial direction centered on the optical axis. The lens described in 1.
The lens according to any one of claims 1 to 6, wherein the plurality of leg portions have a roughened surface.
The first optical surface has a concave shape having a relatively large curvature compared to the second optical surface, and the second optical surface has a convex shape as a whole, and has a locally concave shape in the center. The lens according to any one of claims 1 to 7, comprising:
The lens according to claim 1, wherein the lens is for LED backlight illumination.
A molding die having a transfer surface for injection molding a lens for controlling the traveling direction of light emitted from the light emitting element,
The lens includes a first optical surface, a second optical surface having a larger diameter than the first optical surface, a flat surface provided around the first optical surface and extending substantially perpendicular to the optical axis, A plurality of legs formed so as to protrude from the flat surface;
The plurality of legs are molding dies arranged outside a circle having a diameter of 0.37D with the optical axis as a reference when the lens diameter is D.
The molding die according to claim 10, wherein the plurality of leg portions are arranged inside a circle having a diameter of 0.8D with respect to the optical axis.
The molding die according to claim 10 or 11, wherein the plurality of leg portions are arranged in a range from a diameter of 0.5D to 0.7D with respect to the optical axis.
The molding die according to any one of claims 10 to 12, comprising a release pin for release that is disposed in a portion to which the bottom surfaces of the plurality of leg portions are transferred.
A first mold for molding the first optical surface side of the lens; and a second mold for molding the second optical surface side of the lens;
The first mold includes a core part for forming the first optical surface by transfer, and a peripheral part disposed around the core part to form the flat surface and the plurality of leg parts. The molding die according to any one of claims 10 to 13.