DE102019206266A1 - Method for producing an optical system for a camera device - Google Patents

Abstract

The invention relates to a method for producing an optical system (24) for a camera device. The method comprises the steps of arranging a circuit carrier (28) with electronic components (32) in an injection molding tool (36), applying a first nozzle side (48) to the circuit carrier (28) so that cavities (56) over the electronic components ( 32) are formed, the injection of an elastomer (20) into the cavities (56) so that the electronic components (32) are sealed by the elastomer (20), the application of a second nozzle side (82) on the circuit carrier (28), so that housing cavities (92) are formed, the injection of a thermally conductive plastic (108) into the housing cavities (92) so that a housing (100) is formed, the application of a third nozzle side (116) to the circuit carrier (28), so that an optical element cavity (128) is formed above an image recorder (60), and the injection of an optical elastomer (20) into the optical element cavity (128) so that an optical element (140) is produced is educated.

Description

The present invention relates to a method for producing an optical system for a camera device.

State of the art

Camera systems are used in many areas. For example, such camera systems are used in motor vehicles as an optical camera system for capturing information. The camera systems record the vehicle's surroundings, for example, and provide information for other vehicle systems.

Camera systems consist of an optics carrier in which several lenses are combined, as well as an optics holder and an image sensor.

From the DE 102 20 671 A1 a manufacturing method for a camera unit is known, which is applied in a multi-component injection molding process over an image pickup chip. The tube (camera housing) and lens are made in one piece from plastic. The lens is made of transparent plastic and the tube is made of non-transparent plastic.

In the EP 1 364 412 B1 discloses an injection molding process for making a digital camera. For this purpose, a camera housing for forming optics from a transparent plastic is injection molded over an image pickup chip. In a further step, a prefabricated lens is inserted into the camera housing.

The DE 10 2015 213 575 A1 discloses a manufacturing process in which individual circuit carriers are encapsulated with a highly filled plastic to form a camera housing and the brittle image recorder is pressure-loaded directly with a stamp in the tool. An optical material is then sprayed over the imager chip for cleaning.

Disclosure of the invention

According to the invention, a method for producing an optical system according to claim 1, a camera device with such an optical system according to claim 9 and a motor vehicle with such a camera device according to claim 10 are provided.

The invention specifies a method for producing an optical system for a camera device. The method comprises the steps of arranging a circuit carrier with electronic components in an injection molding tool, applying a first nozzle side to the circuit carrier so that cavities are formed over the electronic components, and injecting an elastomer into the cavities so that the electronic components are sealed by the elastomer the application of a second nozzle side on the circuit carrier so that housing cavities are formed, the injection of a thermally conductive plastic into the housing cavities so that a housing is formed, the application of a third nozzle side on the circuit carrier so that an optical element cavity above an image recorder and injecting an optical elastomer into the optical element cavity so that an optical element is formed.

A nozzle side in the sense of the invention is that part of an injection molding tool through which the plastic material is injected into the cavities that are formed. The cavity represents a hollow space which is mostly filled during injection. According to the invention, there are three different nozzle sides, which each form different cavities in order to form different structures.

A low-viscosity elastomer is preferably used as the elastomer. These elastomers particularly preferably contain an adhesion promoter. In particular, the substances immiscible in the interface can create a close physical or mostly chemical bond through the adhesion promoter. This improves the connection of a further plastic applied to it. Accordingly, the risk of these substances becoming detached is significantly reduced. The elastomer encloses the electronic components airtight, so that they are protected from abrasive fillers.

The heat in the optical system can be effectively conducted to the outside through the thermally conductive plastic forming a housing. This plastic is preferably a thermoset. The optical elastomer is a highly transparent component, so that the image signal can be transmitted through the optical elastomer without significant losses.

As a result of the invention, three different plastic components are sprayed onto the circuit carrier one after the other, so that a plastic component that is optimal in terms of function can be selected for each component of the optical system to be formed.

Advantageous embodiments and developments emerge from the subclaims as well as from the description with reference to the figures.

In a preferred embodiment of the invention, the method steps are carried out at a single production station. A single production station within the meaning of the invention is understood to mean that the circuit carrier does not have to be transported further to carry out the method steps, but rather the method steps are carried out at a fixed position. Accordingly, there is no displacement of the circuit carrier, so that inaccuracies in the alignment of the circuit carrier are avoided. Such an optical system can accordingly be manufactured more precisely. This improves the image quality, especially in the case of optical components.

In a further preferred embodiment of the invention, the circuit carrier is conveyed on to an adjacent production station after the injection. A different material is therefore applied to the circuit carrier at each production station. With such an arrangement, circuit carriers which are arranged, for example, on an endless panel can be manufactured. In addition, the speed of a production can be increased significantly by several production stations, so that the costs for such an optical system can be reduced and it can thus be produced more economically.

Several circuit carriers are preferably processed simultaneously in the manufacturing station. In other words, the injection process is carried out not only on a single circuit carrier, but on several. Production is preferably carried out simultaneously with four circuit carriers. As a result, the optical systems can be manufactured more quickly and thus more economically.

In an advantageous development, the circuit carrier is positioned in the manufacturing station via a latching mechanism. A latching mechanism in the context of the invention is understood to mean two elements which interact with one another in a latching manner when a desired positioning is achieved. One of the elements is arranged on the circuit carrier or the panel, while the other element is attached to the injection molding tool. By locking these two elements, the circuit carrier is positioned in the desired position on the injection mold.

A plurality of latching mechanisms are preferably present in order to limit various possible directions of movement of the circuit carrier. By using a latching mechanism, the circuit carrier can be arranged on the injection molding tool with great accuracy. Accordingly, the material to be injected can be injected at the points provided for it with high accuracy. This produces an optical system with a high quality.

Advantageously, each side of the nozzle is arranged without contact with the image recorder. This means that after the nozzle side has been applied to the circuit carrier, there is always a gap between the image sensor and the nozzle side. This gap can be closed in a subsequent injection process. No pressure or force is therefore applied to the image recorder by applying the nozzle side to the circuit carrier. This can prevent the image sensor from breaking. This reduces the reject rate of defective optical systems and increases profitability. In addition, no superficial damage to the image recorder is generated, which could impair the image quality, so that the quality of the optical systems is increased.

In a further advantageous embodiment, an elastomer layer with a thickness of 100 μm to 300 μm is applied to the image recorder with the first nozzle side. As a result, the image recorder is sealed by the elastomer layer so that contamination of the image recorder can be avoided. The thickness of the elastomer layer is selected in such a way that it has an insignificant effect on the optical quality of the image recorder.

The elastomer layer advantageously has an adhesion promoter, so that better adhesion of the optical elastomer above the image recorder is achieved through the elastomer layer. This avoids detachment with, for example, air pockets, so that the quality of the optical systems is improved.

According to an expedient embodiment, all process steps are carried out at the same injection mold temperature. The injection mold temperature is therefore constant. A temperature between 130 and 180 ° C. is preferably chosen. Due to the constant temperature, the circuit carrier does not experience any significant temperature differences. Temperature fluctuations can cause the injected material to loosen, affecting quality. Because of the constant temperatures, a better connection between the surface and the injected material is achieved.

The invention also provides a camera device with such an optical system Motor vehicle with a driver assistance system that is designed with such a camera device. With such a camera device and such a motor vehicle, the advantages mentioned for the optical system can be achieved.

• 1 Ausführungsbeispiel des erfindungsgemäßen Verfahrens,
• 2 Schnittansicht während des Einspritzens eines Elastomers,
• 3 Draufsicht nach dem Einspritzen des Elastomers,
• 4 Schnittansicht während des Einspritzens eines wärmeleitfähigen Kunststoffes,
• 5 Draufsicht nach dem Einspritzen eines wärmeleitfähigen Kunststoffes,
• 6 Schnittansicht während des Einspritzens eines optischen Elastomers,
• 7 Draufsicht nach dem Einspritzen des optischen Elastomers, und
• 8 Ausführung des Verfahrens mit benachbarten Fertigungsstationen.

Exemplary embodiments of the invention are shown in the drawing and explained in more detail in the description below. It shows:

• 1 Embodiment of the method according to the invention,
• 2 Sectional view during the injection of an elastomer,
• 3 Top view after injecting the elastomer,
• 4th Sectional view during the injection of a thermally conductive plastic,
• 5 Top view after injecting a thermally conductive plastic,
• 6th Sectional view during the injection of an optical elastomer,
• 7th Top view after the injection of the optical elastomer, and
• 8th Execution of the process with neighboring production stations.

In 1 an embodiment of the method according to the invention is shown. The first three procedural steps of the procedure are used in conjunction with the 2 and 3 explained. The 2 shows the sectional view and during the injection of the elastomer 20th and 3 the top view after injection. In 3 is the in 2 Section plane shown shown. In these figures there are four optical systems 24 produced simultaneously. In a first step 26th becomes a circuit carrier 28 which on a benefit 30th is arranged with electronic components 32 in an injection mold 36 arranged. The circuit carrier is used for this 28 via a locking mechanism 40 , which here in the form of a fixing pin 40a and a recess 40b in use 30th is formed on the injection mold 36 positioned.

In a second step 44 becomes a first nozzle side 48 , which has a forming stamp 52 has, on the circuit carrier 28 applied so that cavities 56 over the electronic components 32 be formed. In this exemplary embodiment, a cavity is also used 56 over an imager 60 educated. In a third step 64 becomes the elastomer 20th via injection channels 68 at a first gate 72 into the cavities 56 injected. Via a needle 76 in an injection nozzle 80 becomes the injector 80 closed after the injection process. The electronic components are injected 32 and the imager 60 about the elastomer 20th sealed. In addition to the image recorder 60 a recess 81 educated.

Process steps four and five are used in conjunction with 4th and 5 explained. In the fourth step 88 becomes a second nozzle side 82 on the circuit carrier 28 applied so that housing cavities 92 be formed. The form stamp 52 the second nozzle side 82 is arranged in this embodiment in such a way that it is contactless with the image recorder 60 is applied. The form stamp 52 is therefore not in contact with the imager 60 and an elastomer layer 96 on the imager 60 . The housing cavities 92 are doing this on the elastomer 20th over the electronic components 32 and formed in an area around it, around a corresponding housing 100 to train.

In a fifth step 104 becomes a thermally conductive plastic 108 via a runner 112 in the housing cavities 92 routed so that an enclosure 100 is trained. The case 100 leaves an area above the imager 60 free so that image information can be recorded.

The sixth and seventh procedural steps are used in conjunction with the 6th and 7th explained. In the sixth step 116 becomes a third nozzle side 120 on the circuit board 28 upset. With the form stamp 52 the third nozzle side 120 becomes an optical element cavity 128 above the image sensor 60 educated. In the seventh step 130 is via corresponding injection channels 68 an optical elastomer 132 at a second gate 136 , which at the recess 81 out 3 is arranged, injected, so that an optical element 140 is trained. This optical element 140 has a convex shape in this embodiment.

8th shows an embodiment of the method with adjacent manufacturing stations 144 . Although the procedure, as in the 2 to 7th shown at a single manufacturing station 144 can be executed in the in 8th embodiment shown three manufacturing stations 144 arranged side by side, so that each injection step at a separate manufacturing station 144 is feasible. This makes mass production with endless benefits 30th enables.

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 10220671 A1 [0004]
• EP 1364412 B1 [0005]
• DE 102015213575 A1 [0006]

Claims (10)

A method of manufacturing an optical system (24) for a camera device, the method comprising the steps of: - Arranging a circuit carrier (28) with electronic components (32) in an injection molding tool (36), - Application of a first nozzle side (48) on the circuit carrier (28) so that cavities (56) are formed over the electronic components (32), - Injection of an elastomer (20) into the cavities (56) so that the electronic components (32) are sealed by the elastomer (20), - Application of a second nozzle side (82) on the circuit carrier (28) so that housing cavities (92) are formed, - Injection of a thermally conductive plastic (108) into the housing cavities (92) so that a housing (100) is formed, - applying a third nozzle side (116) to the circuit carrier (28) so that an optical element cavity (128) is formed above an image recorder (60), and - Injection of an optical elastomer (20) into the optical element cavity (128) so that an optical element (140) is formed. Procedure according to Claim 1 , characterized in that the method steps are carried out at a single manufacturing station (144). Procedure according to Claim 1 , characterized in that the circuit carrier (28) is conveyed on to an adjacent production station (144) after the injection. Method according to one of the preceding claims, characterized in that several circuit carriers (28) are processed simultaneously in the production station (144). Method according to one of the preceding claims, characterized in that the circuit carrier (28) is positioned in the production station (144) via a latching mechanism (40). Method according to one of the preceding claims, characterized in that each nozzle side (116) is arranged without contact with the image recorder (60). Method according to one of the preceding claims, characterized in that an elastomer layer (96) with a thickness of 100 µm to 300 µm is applied to the image sensor (60) with the first nozzle side (48). Process according to one of the preceding claims, characterized in that all process steps are carried out at the same injection mold temperature. Camera device with an optical system (24) according to one of the preceding claims. Motor vehicle with a driver assistance system with a camera device according to Claim 9 is designed.

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