KR102439411B1 - Injection prism for rear camera and folded camera, and manufacturing method thereof - Google Patents

Abstract

The present invention relates to an injection prism for a folded camera or a rear camera and a manufacturing method thereof. The method includes: a step (A) of preparing a transparent plastic raw material; and a step (B) of injection-molding a transparent plastic raw material to complete a triangular transparent structure having a polyhedron including an entrance surface, an exit surface, and a bottom surface. In the step (B), injection molding is performed under conditions of an injection speed of 4 to 6 mm/s, an injection position of 11 to 12 mm, a holding pressure of 600 to 700 kgf/cm^2, and a holding pressure of 2 to 4 sec. According to the present invention, it is possible to provide an injection prism for a folded camera or a rear camera by injection molding using a transparent plastic material. The same can be manufactured as a high-quality injection molding product with increased flatness to minimize the occurrence of defects and exhibit excellent performance. It is possible to provide a prism with improved mechanical strength while providing a prism implementing performance equivalent to that of a glass product made of a conventional quartz material.

Description

Injection prism for a folded camera or a rear camera, and a manufacturing method thereof

The present invention relates to an injection prism for a folded camera or a rear camera and a manufacturing method thereof, and more particularly, a folded camera that can be manufactured with a high-quality prism that realizes excellent performance by an injection molding method using a transparent plastic material. It relates to an injection prism for a dragon or rear camera and a manufacturing method thereof.

In general, a prism is used to refract or disperse light, and refers to an optical component having a polyhedral shape.

Such a prism is used in various fields for optical processing of light, and is used, for example, as an optical component in a folded camera for a smartphone or a rear camera for a vehicle.

The prism is arranged and used to refract light incident on a camera module from a folded camera or a rear camera and transmit it to a lens and an image sensor.

As described above, most of the prisms used to refract light by being grafted onto a folded camera or a rear camera are manufactured and utilized as glass products made of quartz material.

However, the conventional prism made of a glass product made of a quartz material is useful in terms of performance, but since the manufacturing process is made in multiple processes, there are problems that it is complicated, takes a long time, and the manufacturing cost is high, and the productivity is not high. In addition, there was a problem in that there was a difficulty in supplying the product because it was not mass-produced.

In addition, since the conventional prism is made of a glass product made of a quartz material, it is weak to impact and has a high risk of breakage.

On the other hand, when looking at the prior art literature related to the prism manufacturing technology, which is an optical component, Korean Patent No. 10-0712336 discloses a 'manufacturing method of a prism', which uses a semiconductor manufacturing process to form a prism structure. As a manufacturing technique, there is a technical difference from the present invention in a manufacturing method.

In addition, Korean Patent Laid-Open No. 10-2021-0027171 discloses a 'prism for an imaging optical system', which includes an incident surface on which light is incident; an exit surface from which light is emitted; It includes; a reflective surface that reflects the light incident through the incident surface to the output surface, wherein the connection portion between the incident surface and the exit surface is filleted to form a single surface. There are technical differences such as differences and differences in manufacturing methods.

Republic of Korea Patent Publication No. 10-0712336 Republic of Korea Patent Publication No. 10-2021-0027171

The present invention has been devised in consideration of and solving the problems of the prior art, and an object of the present invention is to provide an injection prism for a folded camera or a rear camera manufactured by injection molding using a transparent plastic material, and a manufacturing method thereof.

The present invention is an injection prism for a folded camera or a rear camera that is manufactured by injection molding using a transparent plastic material, but with a high-quality prism with increased flatness to minimize the occurrence of defects and exhibit excellent performance, and a method for manufacturing the same Its purpose is to provide

The present invention is a folded camera that simplifies the manufacturing process compared to existing quartz glass products to reduce manufacturing time and unit cost, increases productivity such as enabling mass production, and enables manufacturing of prisms strong against impact An object of the present invention is to provide an injection prism for use or a rear camera and a method for manufacturing the same.

An ejection prism for a folded camera or a rear camera according to the present invention for achieving the above object is a triangular transparent structure having a polyhedron, and an incident surface through which light is incident and refracts or transmits light toward the output surface; It is a product obtained by injection molding a transparent plastic material, including an exit surface perpendicular to the incident surface and emitting light, and a bottom surface connecting the incident surface and the emission surface, and the transparent plastic material is a cyclic olefin polymer (COP). ; cyclic olefin polymer), cyclic olefin copolymer (COC: Cyclic Olefin Copolymer), polycarbonate (PC), polymethyl methacrylate (PMMA) may be a configuration in which one or two or more selected from the mixture is used.

Here, the transparent plastic material is a cyclic olefin copolymer (COC: Cyclic Olefin Copolymer) capable of dimensional stability, low shrinkage and volumetric precision when two or more types are mixed and used, and a cyclic olefin polymer (COP) that is not easily broken and has excellent transparency ; cyclic olefin polymer) may be of a configuration including at least one essential material.

Here, an AR (anti-reflection) coating layer is formed on the incident surface and the exit surface, a mirror coating layer is formed on the bottom surface, and a blackening coating layer is formed on both sides shared by the incident surface, the exit surface, and the bottom surface. can

Here, the triangular transparent structure having the polyhedron is formed to have a length of 7 to 8 mm, each of which has a width of 5 to 6 mm on an incident surface and an exit surface, and is made of a small size having a width of 6 to 7 mm on the bottom surface, The incident surface and the exit surface are formed to have the same width, and the bottom surface is flat that satisfies an aberration of 1/6 to 1/12 in the P-V (Peak to Valley) index indicating the difference between the highest and lowest points. It may be a configuration having a diagram.

In addition, the method for manufacturing an injection prism for a folded camera or a rear camera according to the present invention for achieving the above object, (A) providing a transparent plastic raw material; (B) injection molding a transparent plastic raw material to complete the triangular transparent structure having a polyhedron including an incident surface, an exit surface, and a bottom surface; It is characterized in that injection molding is performed under the conditions of s, injection position 11 to 12 mm, holding pressure 600 to 700 kgf/cm2, and holding pressure time 2 to 4 sec.

Here, in the step (B), injection molding may further include injection molding under a temperature condition of 200 to 210° C. on the injection cylinder side and 100 to 120° C. on the molding die side.

Here, the transparent plastic raw material is selected from cyclic olefin polymer (COP), cyclic olefin copolymer (COC), polycarbonate (PC), and polymethyl methacrylate (PMMA). Cyclic Olefin Copolymer (COC) that is capable of dimensional stability, low shrinkage and volumetric precision when two or more types are mixed and used, and cyclic olefin polymer with excellent transparency without breaking (COP; cyclic olefin polymer) may be of a configuration including at least one essential material.

Here, (C) forming a coating layer on the surface of the triangular transparent structure having a polyhedron; includes, an AR (anti-reflection) coating layer is formed on the incident surface and the exit surface, and a mirror coating layer is formed on the bottom surface, , it may be configured to form a blackening coating layer on both sides shared by the incident surface, the exit surface, and the bottom surface.

Here, the triangular transparent structure having the polyhedron is formed to have a length of 7 to 8 mm, each of which has a width of 5 to 6 mm on an incident surface and an exit surface, and is made of a small size having a width of 6 to 7 mm on the bottom surface, The incident surface and the exit surface are formed with the same width, and the bottom surface has a flatness that satisfies the aberration of 1/6 to 1/12 in the P-V (Peak to Valley) index indicating the difference between the highest and lowest points. It may be a configuration having

According to the present invention, it is possible to provide an injection prism for a folded camera or a rear camera manufactured by injection molding using a transparent plastic material.

According to the present invention, a high-quality prism for a folded camera or a rear camera with increased flatness to minimize defects and exhibit excellent performance by using a transparent plastic material and manufacturing it by injection molding in consideration of the physical properties of the material used can provide

According to the present invention, the manufacturing process can be simplified compared to the existing quartz glass products, and the manufacturing time and unit cost can be reduced, and the productivity can be increased, such as mass production, and it is strong against impact. Alternatively, a prism for the rear camera may be provided.

According to the present invention, it is possible to provide a prism that not only provides mechanical strength through a transparent plastic product made by injection molding, but also can increase flatness, and implements performance comparable to that of a glass product made of a conventional quartz material. .

Advantageous Effects of Invention According to the present invention, it is possible to provide the usefulness of eliminating size tolerance and producing in a uniform standard as compared to a prism of a glass product made of a conventional quartz material.

1 is a perspective view showing an ejection prism for a folded camera or a rear camera according to an embodiment of the present invention.
2 is a perspective view illustrating a configuration including a coating layer in an injection prism for a folded camera or a rear camera according to an embodiment of the present invention.
3 is a schematic block process diagram illustrating a method of manufacturing an injection prism for a folded camera or a rear camera according to an embodiment of the present invention.
4 is a sample product showing an ejection prism for a folded camera or a rear camera according to an embodiment of the present invention.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings, and the purpose and configuration of the present invention and its features will be better understood through such detailed description.

As shown in FIGS. 1 and 2, the injection prism 100 for a folded camera or a rear camera according to an embodiment of the present invention is an injection-molded product using a transparent plastic material, and a triangular transparent structure having a polyhedron. is made of

That is, the incident surface 110 through which light is incident and refracts or transmits light toward the exit surface, the exit surface 120 perpendicular to the incident surface and light is emitted, and a floor connecting the incident surface and the exit surface surface 130 .

As the transparent plastic material, one selected from cyclic olefin polymer (COP), cyclic olefin copolymer (COC), polycarbonate (PC), and polymethyl methacrylate (PMMA) It may be used alone or in combination of two or more.

At this time, in the transparent plastic material, when two or more types are mixed and used, a cyclic olefin copolymer (COC) capable of volumetric precision due to dimensional stability and low shrinkage and a cyclic olefin polymer (COP) that is not easily broken and has excellent transparency A configuration including at least one of them as an essential material is preferable.

Sometimes, it will be said that a mixture of two types of a cyclic olefin polymer (COP) and a cyclic olefin copolymer (COC) can be used as the transparent plastic material.

Here, since the cyclic olefin copolymer (COC) is transparent, it is possible to realize fine details during injection molding, has dimensional stability, and has a low shrinkage rate, physical properties that can increase volumetric precision can be utilized.

Here, the cyclic olefin polymer (COP) has excellent transparency and heat resistance as well as unbreakable mechanical strength, and can utilize the physical properties of dimensional stability.

In addition, on the triangular transparent structure having the polyhedron, an AR (anti-reflection) coating layer is formed on the incident surface 110 and the exit surface 120, and a mirror coating layer is formed on the bottom surface 130, and the incident surface ( A blackening coating layer may be formed on both left and right side surfaces shared by 110 ) and the emission surface 120 and the bottom surface 130 .

In addition, the prism (100) by increasing the degree of freedom such as freely adjusting the transmission of light through aspherical grafting may be configured to form an aspherical surface with respect to the incident surface or an aspherical surface for each of the incident surface and the output surface. ) can improve the performance of

The triangular transparent structure having the polyhedron, that is, the ejection prism 100 for a folded camera or a rear camera according to an embodiment of the present invention is formed with a length of 7 to 8 mm, but the incident surface 110 and the output surface 120 Each width is 5 to 6 mm, the bottom surface 130 is made of a small size having a width of 6 to 7 mm, and the incident surface 110 and the exit surface 120 are formed to have the same width.

In addition, in the bottom surface 130 , it satisfies the aberration (degree of distortion) of 1/6 to 1/12 in the P-V (Peak to Valley) index indicating the difference between the highest and lowest points, thereby providing excellent flatness. It is preferable to form to have a degree.

The emitting surface 120 may be configured to be formed as a convex curved surface having a slightly convex shape to maintain high transmittance while inducing and reducing the loss of the straightness of the emitted light.

On the other hand, if the manufacturing method of the injection prism 100 for a folded camera or a rear camera according to an embodiment of the present invention will be described as follows,

As shown in FIG. 3, the method for manufacturing an injection prism for a folded camera or a rear camera according to an embodiment of the present invention comprises a process including a transparent plastic providing step (S10) and an injection molding step (S20).

In addition, it may include a coating step (S30) after the injection molding step (S20).

The transparent plastic providing step (S10) is a step of providing a transparent plastic raw material.

In this case, the transparent plastic raw material is basically a cyclic olefin polymer (COP) having excellent light transmittance, a cyclic olefin copolymer (COC: Cyclic Olefin Copolymer), polycarbonate (PC), polymethyl methacrylate ( PMMA), one type or two or more types selected from the group consisting of PMMA) may be used in combination.

Here, when two or more types are mixed for the transparent plastic raw material, the cyclic olefin copolymer (COC) capable of volumetric precision due to dimensional stability and low shrinkage and the cyclic olefin polymer (COP) with excellent transparency without breaking easily ), a configuration including at least one of them as an essential material is preferable.

Sometimes, it will be said that a mixture of two types of cyclic olefin polymer (COP) and cyclic olefin copolymer (COC) can be used as the raw material for the transparent plastic.

The injection molding step (S20) is a step of completing the shape of the prism product by injection molding the transparent plastic raw material prepared through the transparent plastic providing step (S10).

That is, the injection molding step (S20) is completed as a triangular transparent structure having a polyhedron including an incident surface 110, an exit surface 120, and a bottom surface 130, as shown in FIGS. 1 and 2 . is a step

The injection molding step (S20) can be divided into an injection process and a molding process. For the injection process, an injection machine that transfers and supplies the transparent plastic raw material while melting is used, and for the molding process, the molten transparent plastic supplied from the injection machine is press-molded. forming molds are used.

The injection machine has a configuration including an injection cylinder, a transfer screw installed to rotate inside the injection cylinder, and a nozzle for injecting the transparent plastic molten at the end of the injection cylinder into a molding mold.

The molding mold has a configuration including an upper mold and a lower mold in which a cavity space for molding the molten transparent plastic into a prism shape is formed.

In the injection molding step (S20), in order to prevent and minimize the occurrence of defects in consideration of the physical properties of the transparent plastic raw material, an injection speed of 4 to 6 mm/s, an injection position of 11 to 12 mm, a holding pressure of 600 to 700 kgf/cm2, a holding time of 2 to It is preferable to perform under the condition of 4 sec.

At this time, the injection cylinder should have a temperature condition of 200 ~ 210 ℃, and the nozzle should have a slightly higher temperature condition than that of the injection cylinder. For example, the nozzle is preferably at a temperature of 230±20° C. in order to increase the injection efficiency.

The injection position means that the transfer screw is moved forward in the injection cylinder by the position set at the set pressure and speed regardless of time.

Here, in the injection speed, when it is less than 4 mm/s, there is a problem that unmolding occurs and a flow mark is generated, and when it exceeds 6 mm/s, there is a problem that a weld line is generated. .

Here, in the injection position, when it is less than 11 mm, there is a problem that molding shrinkage occurs and a weld line and a flow mark are generated, and when it exceeds 12 mm, there is a weld line and a flow mark. There is a problem that a mark (flow mark) is generated.

Here, in the holding pressure, when the pressure is less than 600kgf/cm2, there is a problem that unmolding occurs and the molding shrinkage increases, and when it exceeds 700kgf/cm2, there is a problem in that cracks are generated due to product bite or impingement in the molding mold.

Also, in the holding pressure time, the numerical limitation of the minimum value and the maximum value is the same as the reason for limiting the holding pressure condition described above.

Here, in the temperature condition of the injection cylinder, when the temperature is less than 200 ℃, there is a problem that the transparency is lowered and injection is impossible due to turbidity, and when it exceeds 210 ℃, there is a problem that the molding defect rate is increased.

In the flow mark, the resin cooled in the sprue or runner part on the molding die side is cooled again in the cavity to have a high viscosity, and is solidified again by the cold molding mold wall surface. At this time, it means that the semi-solidified resin is pushed by the following molten resin, and a stripe shape perpendicular to the flow direction appears.

In the above, the weld line is a thin line that occurs at a place where the flow of resin joins during injection molding, and it appears as an optical or mechanical defect on a plastic part, and means a defect that occurs more clearly in a transparent product.

In addition, in the injection molding step (S20), in order to prevent and minimize the occurrence of defects, it is preferable to carry out under a temperature condition of 100 ~ 120 ℃ on the mold side.

As described above, through the injection molding step (S20) performed under the condition of the numerical limitation described above, the incident surface 110 through which light is incident and refracts or transmits light toward the exit surface, and the incident surface and the An injection prism using a transparent plastic raw material made of a triangular transparent structure having a polyhedron, including an exit surface 120 at a right angle and from which light is emitted, and a bottom surface 130 connecting the incidence surface and the exit surface can be manufactured. have.

At this time, in the bottom surface 130 , it satisfies the aberration (degree of distortion) of 1/6 to 1/12 in the P-V (Peak to Valley) index indicating the difference between the highest and lowest points, thereby providing excellent flatness. It is possible to manufacture an injection prism for a folded camera or a rear camera with a structure having a diagram.

4 shows a sampling product of an injection molding method for use as an injection prism for a folded camera, and shows an ultra-small injection prism manufactured under the above-described injection molding conditions using the above-described transparent plastic raw material, and has a length of 7.5 mm. , each having a width of 5.9 m on the incident surface 110 and the exit surface 120 , and 6.7 mm on the bottom surface 130 .

In FIG. 4, injection molding using a cyclic olefin polymer (COP) (see the right photo of FIG. 4) or a cyclic olefin copolymer (COC: Cyclic Olefin Copolymer) (see the left photo of FIG. 4) alone A miniature ejection prism is shown.

The coating step (S30) is a step of forming a coating layer on the surface of the triangular transparent structure having a polyhedron completed through the injection molding step (S20) to improve the function of the prism.

In the coating step (S30), an AR (anti-reflection) coating layer is formed on the incident surface 110 and the output surface 120, a mirror coating layer is formed on the bottom surface, and the left and right side surfaces shared by the incident surface, the output surface, and the bottom surface A blackening coating layer may be formed thereon.

Accordingly, through the present invention described above, it is possible to provide an injection prism for a folded camera or a rear camera by injection molding using a transparent plastic material, and to minimize the occurrence of defects during injection molding and improve the flatness to exhibit excellent performance. It can be manufactured as a high-quality injection product, and it can exhibit the advantage of providing a prism with increased mechanical strength while providing a prism that realizes performance equivalent to a glass product made of a conventional quartz material.

In addition, it can be manufactured by simplifying the manufacturing process compared to the existing quartz glass products (prism), manufacturing time and unit cost can be reduced, mass production is possible, and productivity can be increased. Compared to the prism of glass products, it can provide the advantage of eliminating size tolerance and producing with a uniform size.

The embodiments described above are only to describe preferred embodiments of the present invention and are not limited to these embodiments, and various modifications and variations by those skilled in the art within the spirit and claims of the present invention Or it will be said that the substitution of steps may be made, and this will be said to be within the scope of the technical rights of the present invention.

100: ejection prism
110: incident surface
120: exit surface
130: bottom surface
S10: Transparent plastic preparation stage
S20: injection molding step
S30: coating step

Claims (9)

As a triangular transparent structure having a polyhedron,
an incident surface through which light is incident and refracts or transmits light toward the exit surface;
an emitting surface perpendicular to the incident surface and from which light is emitted; and
It includes a bottom surface connecting the incident surface and the exit surface, and is a product obtained by injection molding a transparent plastic material,
The transparent plastic material is one or two selected from cyclic olefin polymer (COP), cyclic olefin copolymer (COC), polycarbonate (PC), and polymethyl methacrylate (PMMA). More than one species is mixed and used,
The triangular transparent structure having the polyhedron,
It is formed with a length of 7 to 8 mm, but is made of a small size with a width of 5 to 6 mm of each of the entrance and exit surfaces, and a width of 6 to 7 mm at the bottom,
The incident surface and the exit surface are formed with the same width,
The bottom surface is for a folded camera, characterized in that it has a flatness that satisfies an aberration of 1/6 to 1/12 in a PV (Peak to Valley) index indicating the difference between the highest point and the lowest point. Ejection prism for rear camera. The method of claim 1,
The transparent plastic material is
At least one of a cyclic olefin copolymer (COC) capable of dimensional stability, low shrinkage and volumetric precision when two or more types are mixed and a cyclic olefin polymer (COP) that is not easily broken and has excellent transparency An injection prism for a folded camera or a rear camera, characterized in that it comprises an essential material. The method of claim 1,
An AR (anti-reflection) coating layer is formed on the incident surface and the exit surface,
A mirror coating layer is formed on the bottom surface,
An ejection prism for a folded camera or a rear camera, characterized in that a blackening coating layer is formed on both sides of the incident surface, the exit surface, and the bottom surface. delete (A) providing a transparent plastic raw material;
(B) injection molding a transparent plastic raw material to complete the triangular transparent structure having a polyhedron including an incident surface, an exit surface, and a bottom surface; includes,
In step (B),
Injection molding is performed under the conditions of injection speed 4~6mm/s, injection position 11~12mm, holding pressure 600~700kgf/cm2, holding pressure 2~4sec,
The triangular transparent structure having the polyhedron,
It is formed with a length of 7-8 mm, but is made of a small size with a width of 5-6 mm on each of the entrance and exit surfaces, and a width of 6-7 mm on the bottom,
The incident surface and the exit surface are formed with the same width,
The bottom surface for a folded camera or rear, characterized in that it has a flatness that satisfies an aberration of 1/6 to 1/12 in the PV (Peak to Valley) index indicating the difference between the highest and lowest points. A method of manufacturing an injection prism for a camera. 6. The method of claim 5,
In step (B),
A method for manufacturing an injection prism for a folded camera or a rear camera, characterized in that injection molding is performed under a temperature condition of 200 to 210°C on the injection cylinder side and 100 to 120°C on the mold side. 6. The method of claim 5,
The transparent plastic raw material is,
One or two or more selected from cyclic olefin polymer (COP), cyclic olefin copolymer (COC), polycarbonate (PC), and polymethyl methacrylate (PMMA) and
At least one of a cyclic olefin copolymer (COC) capable of dimensional stability, low shrinkage and volumetric precision when two or more types are mixed and a cyclic olefin polymer (COP) that is not easily broken and has excellent transparency A method for manufacturing an injection prism for a folded camera or a rear camera, comprising as an essential material. 6. The method of claim 5,
(C) forming a coating layer on the surface of the triangular transparent structure having a polyhedron; includes,
An AR (anti-reflection) coating layer is formed on the incident surface and the exit surface,
A mirror coating layer is formed on the bottom surface,
A method for manufacturing an injection prism for a folded camera or a rear camera, characterized in that a blackening coating layer is formed on both sides shared by the incident surface, the exit surface, and the bottom surface. delete

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