Optical sensor module

Abstract

The utility model provides an optical sensor module. An example optical sensor module includes a light emitting device; a light receiving sensor; and a module cover adapted to at least partially cover the light emitting device and the light receiving sensor, the module cover being a molded cover, the molded cover being formed of a molding material, the molding material comprising electrically conductive particles dispersed therein for providing electromagnetic interference shielding.

Description

[0001] Cross-references to (one or more) related applications

[0002] This application claims priority to French patent application No. 2311561 entitled “Module de Capteur Optique”, filed on October 25, 2023, which is incorporated herein by reference to the fullest extent permitted by law. Technical Field

[0003] This disclosure generally relates to optical sensors, and more particularly to optical sensor modules. Background Technology

[0004] Optical sensors, such as proximity sensors, can be used to detect the presence of nearby objects. Optical sensors can do this without physically contacting the object. Some types of optical sensors, such as those used in optical rangefinders or time-of-flight sensors, can be used to determine the actual distance to such a nearby object. Optical sensors can be used in a variety of electronic devices, such as cameras, telephones (including smartphones), smartwatches, tablets, vehicles, machinery, and other devices used to detect the presence of nearby objects and / or the distance to those objects. After detecting the presence of a nearby object, the electronic device can be configured to perform functions such as moving a mechanical feature to a safe position, sending an alarm signal, coupling or decoupling electrical communications, or any other desired function.

[0005] Optical sensors typically include components such as light emitting devices, light receiving sensors, and processing devices generally used to process signals received from the light receiving sensors. The components of an optical sensor can be formed on a substrate, and a cover can be attached to the substrate over the components, for example, to protect them from damage, thereby forming an optical sensor module, also known as an optical sensor package. The cover is generally formed with a first opening above the light emitting device and a second opening above the light receiving sensor.

[0006] Generally, the light emitting device emits a light signal through a first opening. If an object is outside the optical sensor module and sufficiently close to it, the light signal can be reflected by the object through a second opening toward the light receiving sensor. The light receiving sensor can then generate an electrical signal indicating the received light signal, which can be transmitted to a processing device for processing the received light signal, for example, to determine the presence of a nearby object and / or the distance to that object.

[0007] There is a need to improve optical sensor modules, particularly to address electromagnetic interference (EMI) issues between optical sensor modules and other electronic devices, such as electronic devices that contain optical sensor modules. Utility Model Content

[0008] One embodiment addresses all or some of the drawbacks of known optical sensor modules.

[0009] One embodiment provides an optical sensor module, the optical sensor module comprising:

[0010] - Optical emitting equipment;

[0011] - Optical receiving sensor; and

[0012] - A module cover, adapted to at least partially cover an optical emitting device and an optical receiving sensor, the module cover being a molded cover formed of a molding material comprising electrically conductive particles dispersed therein to provide electromagnetic interference shielding.

[0013] One embodiment provides an optical sensor module, the optical sensor module comprising:

[0014] - Optical emitting equipment;

[0015] - Optical receiving sensor;

[0016] - A module cover, adapted to at least partially cover an optical emitting device and an optical receiving sensor, the module cover being a molded cover;

[0017] - A substrate, assembled with a module cover, wherein a light emitting device is included in a first die mounted on the substrate, and a light receiving sensor is included in a second die mounted on the substrate; and

[0018] - Conductive leads, assembled with or included in the module cover, and the conductive leads being coupled to a first conductive pad on the substrate; and

[0019] - At least one cover glass, covering at least one opening of the module cover, each cover glass including conductive traces that provide electromagnetic interference shielding, the conductive traces being coupled to conductive leads.

[0020] In one embodiment, the molded cover is formed of a molding material comprising electrically conductive particles dispersed therein to provide electromagnetic interference shielding.

[0021] In one embodiment, the module cover is adapted to absorb electromagnetic waves, and / or has a strength of less than 10. 4 Surface resistivity in ohms / square, and / or relative permeability greater than 100.

[0022] In one embodiment, the module cover is an injection-molded cover, and / or the molding material is a resin, a liquid crystal polymer, or another engineering plastic.

[0023] In one embodiment, the electrically conductive particles include one or more of the following:

[0024] - Carbon fiber;

[0025] - Short-cut carbon fibers;

[0026] - Electroplated carbon fiber, such as nickel-plated (Ni) carbon fiber;

[0027] - Carbon nanotubes;

[0028] - Conductive carbon black particles;

[0029] - Stainless steel fiber.

[0030] In one embodiment, the module cover includes a metallic finishing layer for increasing electromagnetic interference shielding.

[0031] In one embodiment, the module cover includes a partition wall adapted to separate the light emitting device and the light receiving sensor.

[0032] In one embodiment, the module further includes a substrate assembled with a module cover, an optical emitting device being included in a first die mounted on the substrate, and an optical receiving sensor being included in a second die mounted on the substrate.

[0033] In one embodiment, the module further includes conductive leads assembled with or included in the module cover, and the conductive leads coupled to a first conductive pad of a substrate, for example using a conductive adhesive material. The substrate includes conductive rails configured to be at a fixed voltage, such as ground, and the conductive rails are coupled to at least one first conductive pad of the first conductive pad.

[0034] In one embodiment, the conductive leads are either inserted into channels in the module cover or encased in a molded lead frame within the module cover.

[0035] In one embodiment, the conductive leads are conductive layers formed on the surface of the module cover, such as by direct forming laser technology.

[0036] In one embodiment, the module cover includes a first opening above the light emitting device and a second opening above the light receiving sensor; and the module further includes:

[0037] - A first cover glass, positioned in the first opening or between the first opening and the light emitting device, and the first cover glass is adapted to transmit light signals emitted by the light emitting device; and

[0038] - A second cover glass, positioned in the second opening or between the second opening and the light receiving sensor, and the second cover glass is adapted to transmit light signals reflected toward the light receiving sensor.

[0039] In one embodiment, the first cover glass and / or the second cover glass includes conductive traces that provide electromagnetic interference shielding.

[0040] In one embodiment, the conductive trace is coupled to at least one conductive lead in the conductive leads.

[0041] In one embodiment, each cover glass also includes a second conductive pad coupled to a conductive trace, the conductive lead being coupled to the second conductive pad, for example using a conductive adhesive material.

[0042] In one embodiment, the first cover glass and / or the second cover glass further includes at least one second conductive pad coupled to the conductive trace, wherein at least one conductive lead of the conductive lead is coupled to the at least one second conductive pad, for example using a conductive adhesive material.

[0043] In one embodiment, the conduction trace includes substantially linear portions that are parallel to each other and spaced apart by a distance less than or equal to a fraction of the wavelength of the electromagnetic signal to be attenuated.

[0044] In one embodiment, the conductive trace material includes one or more of the following materials: copper, aluminum, tungsten, titanium, gold, and indium tin oxide. Attached Figure Description

[0045] The foregoing features and advantages, as well as others, will be described in detail in the following description of specific embodiments given by way of illustration rather than limitation with reference to the accompanying drawings, in which:

[0046] Figure 1A This is a 3D view of an optical sensor module according to one embodiment;

[0047] Figure 1B yes Figure 1A An exploded 3D view of the optical sensor module;

[0048] Figure 1C yes Figure 1A Top view of the optical sensor module;

[0049] Figure 1D yes Figure 1A A cross-sectional view of the optical sensor module;

[0050] Figure 2A yes Figure 1A Top view of the cover glass of the optical sensor module;

[0051] Figure 2B This is a top view of another cover glass of an optical sensor module according to another embodiment;

[0052] Figure 3A This is a 3D view of the module cover of an optical sensor module according to yet another embodiment; and

[0053] Figure 3B yes Figure 3A A cross-sectional view of the optical sensor module. Detailed Implementation

[0054] Similar features have been designated by similar reference numerals in the various figures. Specifically, structural and / or functional features common to the various embodiments may have the same reference numerals and may have the same structure, dimensions, and material properties.

[0055] For clarity, only operations and elements useful for understanding the embodiments described herein are illustrated and described in detail. Specifically, not all components of the optical sensor are detailed, and the embodiments are compatible with conventional optical sensors. For example, light emitting devices, light receiving sensors, and other components of the optical sensor (such as processing devices) are not detailed. Similarly, not all components of the optical sensor module are detailed, and the embodiments are compatible with conventional optical sensor modules.

[0056] Unless otherwise indicated, when referring to two elements connected together, it means that there is no direct connection between them except for the conductor; and when referring to two elements coupled together, it means that the two elements can be connected or that they can be coupled via one or more other elements.

[0057] In the following disclosure, unless otherwise indicated, when referring to absolute position qualifiers such as the terms “front,” “back,” “top,” “bottom,” “left,” “right,” etc., or relative position qualifiers such as the terms “above,” “below,” “higher than,” “lower than,” etc., or orientation qualifiers such as “horizontal,” “vertical,” etc., refer to the orientation shown in the figures, or refer to the orientation of the optical sensor module as it is during normal use.

[0058] Unless otherwise stated, the expressions “approximately,” “about,” “basically,” and “roughly” indicate within 10%, and preferably within 5%.

[0059] In the following disclosure, unless otherwise indicated, when referring to resistivity, reference shall be made to electrical resistivity. Similarly, when referring to conductive elements, reference shall be made to electrical conductive elements.

[0060] The term "optical sensor module" includes, but is not limited to, proximity sensor modules, time-of-flight (ToF) modules, ambient light sensor (ALS) modules, 3D LiDAR modules, and / or camera modules. The term "optical sensor module" also includes optical sensor modules with combined functions (e.g., a combination of at least two of the modules mentioned above), or optical sensor modules with other functions (e.g., a combination of a proximity detector module with a floodlight and / or a spot projector).

[0061] The embodiments relate to an optical sensor module. An optical sensor typically includes a light-emitting device (such as a light-emitting diode (LED) or a laser such as a vertical-cavity surface-emitting laser (VCSEL)) and a light-receiving sensor (such as a photodiode or multiple photodiodes). The optical sensor also generally includes processing means for processing the signal received from the light-receiving sensor. The light-emitting device and the light-receiving sensor can be formed on a substrate, for example, each in a separate die attached to the substrate, and a cover can be bonded to the substrate above the light-emitting device and the light-receiving sensor, thereby forming an optical sensor module, also known as an optical sensor package. The cover is generally formed with a first opening above the light-emitting device and a second opening above the light-receiving sensor.

[0062] Optical sensor modules may be affected by electromagnetic interference (EMI) from other electronic devices.

[0063] For example, when an optical sensor module is included in an electronic device (host device), electromagnetic interference (EMI) may occur between the optical sensor module and the host device. The electronic device may be a camera, a telephone (e.g., a smartphone), a smartwatch, a tablet, a vehicle, machinery, or another device that may be useful for detecting the presence of nearby objects and / or the distance to nearby objects.

[0064] Electromagnetic interference between the optical sensor module and the host device may include:

[0065] - Electromagnetic waves emitted by components of the optical sensor module that may affect components of the host device; and / or

[0066] - Electromagnetic waves emitted by the host device that may affect the performance of the optical sensor module.

[0067] In addition, the environment (such as environments with large electromagnetic waves, such as data centers) may also interfere with the components of the optical sensor module and affect its performance.

[0068] One solution to the electromagnetic interference problem is to add a metal shield above the optical sensor module, specifically, to add a metal shield above the electromagnetically sensitive components of the optical sensor module.

[0069] The metal used for metal shielding is preferably selected as:

[0070] - Reflects and / or absorbs electromagnetic waves generated by the optical sensor module to prevent electromagnetic waves from leaving the optical sensor module and affecting the host device, and / or

[0071] - Reflects and / or absorbs electromagnetic waves generated by the host device or from the environment to prevent electromagnetic waves from affecting the performance of the optical sensor module.

[0072] Metal shields can be grounded to further improve the effectiveness of EMI protection, such as for effective absorption of electric fields.

[0073] However, metal shielding can have several drawbacks. For example, it may increase the footprint of the optical sensor module. Depending on the method used, the fabrication of metal shielding may introduce numerous steps and / or result in high production costs, may require large tolerances (which can be problematic, for example, for small optical sensor modules), and / or may inefficiently form complex shapes. The fabrication process may also introduce gaps in the metal shielding, which may allow electromagnetic waves to pass through. The choice of materials for metal shielding may also be limited. Furthermore, implementing grounding schemes on metal shielding can be difficult.

[0074] In addition to the potential drawbacks mentioned above, another issue with openings in optical sensor modules involves having an opening within a metallic shield that is then unshielded, allowing electromagnetic waves to pass through. Depending on the frequency of the electromagnetic waves, the size of the opening can be adapted to manage electromagnetic interference. For example, the opening size can be included between 1 and 5 mm, or even between 0.1 and 5 mm. However, for certain frequencies, such as those above 20 GHz, or above 30 GHz, or even above 300 GHz, an opening of 5 mm, 1 mm, or even 0.5 mm may be too large to manage EMI.

[0075] The inventors have proposed an optical sensor module that overcomes all or some of the above-mentioned drawbacks, particularly solving the electromagnetic interference problem. It uses a simple solution that avoids increasing the space occupied by the optical sensor module and avoiding complicating the manufacturing process, and it can form complex shapes with small tolerances.

[0076] It is also desirable that the solution can manage electromagnetic interference passing through the opening.

[0077] Embodiments of the optical sensor module will now be described. These embodiments are non-limiting, and various variations will become apparent to those skilled in the art based on the indications in this description.

[0078] Figure 1AThis is a 3D view of an optical sensor module 100 according to one embodiment. Figure 1B yes Figure 1A An exploded 3D view of the optical sensor module. Figure 1B The exploded view makes it easier to see the different components of the optical sensor module 100. Figure 1C yes Figure 1A A top view of the optical sensor module. Figure 1D yes Figure 1A A cross-sectional view of the optical sensor module. The cross-section is in the AA direction, which allows for... Figure 1A and Figure 1C I saw it in the middle.

[0079] The optical sensor module 100 includes a light emitting device 112 (e.g., including an LED such as an infrared LED, or a laser such as a VCSEL, or a laser such as an edge-emitting laser (EEL)) and a light receiving sensor 122 (e.g., including a photodiode such as one or more SPADs or multiple photodiodes), the light emitting device 112 and the light receiving sensor 122 being formed on a substrate 102.

[0080] The substrate 102 may be a printed circuit board (PCB).

[0081] The light emitting device 112 is configured to emit a light signal at a specific frequency or frequency range, and the light receiving sensor 122 is adapted to detect the returned (e.g., reflected by an object) emitted light signal. In one embodiment, the light emitting device 112 is configured to emit an infrared (IR) light signal, and the light receiving sensor 122 is adapted to detect the returned (e.g., reflected by an object) IR light signal.

[0082] The light emitting device 112 is included in the first die 110, and the light receiving sensor 122 is included in the second die 120. The first die and the second die are mounted on the top surface 102A of the substrate 102.

[0083] The first die 110 and the second die 120 can be coupled to the substrate 102 using conductive connectors (e.g., via first conductive line 141 and second conductive line 142, respectively). For example, a first end of each first conductive line (and the second conductive line, respectively) is coupled to a conductive pad on the first die (and the second die, respectively). Figures 1A-1D (not shown in the image), and the second end of each first conductive line (and respectively, the second conductive line) is coupled to a conductive pad on the top surface 102A of the substrate 102. The first die 110 and the second die 120 can be attached to the substrate 102, such as by an adhesive material or solder. The adhesive material can be any material suitable for attaching the die to the substrate, such as tape, paste, glue (…). Figures 1A-1D (Not shown in the image).

[0084] The light emitting device 112 can be electrically coupled to the light receiving sensor 122, for example, via the substrate 102 and the first die 110 and the second die 120.

[0085] Generally, the optical sensor module 100 includes processing devices for processing signals received from the light receiving sensor 122. Figures 1A-1D (Not shown in the image). The processing device may be included in the second die 120 or in another die.

[0086] The top surface 102A of the substrate 102 includes a first conductive pad 106, which is located, for example, at or near the edge of the substrate.

[0087] A module cover 130 having a first opening 131 and a second opening 132 is attached or bonded to a substrate 102 and is adapted to at least partially surround or cover the first die 110 and the second die 120. At least partially means, for example, that the first and second openings do not cover the first and second dies. The module cover 130 may be substantially opaque to light at the wavelength in use.

[0088] For example, the module cover 130 is mounted on an opaque adhesive 104 that is attached to the substrate 102.

[0089] The first and second openings are located in the top surface 130A of the module cover 130. The first opening 131 is located above the light emitting device 112, and the second opening 132 is located above the light receiving sensor 122. In the illustrated example, the first opening 131 is rectangular and the second opening 132 is circular, but this is not limiting, and other forms are possible.

[0090] The module cover 130 may include a partition wall 134 between the first die 110 and the second die 120. The partition wall 134 may form an optical isolation portion to substantially prevent the internal propagation of a light beam between the light emitting device 112 and the light receiving sensor 122 within the module cover 130. For example, the partition wall 134 defines two cavities, each having one of a first opening and a second opening.

[0091] The module cover 130 is a molded cover formed of a molding material (such as resin, liquid crystal polymer (LCP), nylon or another engineering plastic) that is compounded with electrically conductive particles dispersed therein to provide electromagnetic interference shielding.

[0092] The module cover 130 can be formed using injection molding.

[0093] For example, molded materials that include electrically conductive particles are suitable for absorbing electromagnetic waves (EMI absorption).

[0094] For example, molded materials that include electrically conductive particles have high permeability. Typically, the relative permeability of molded materials can be higher than 100, although higher is better for EMI attenuation. For reference, a high-permeability material is iron (99.8% purity), whose relative permeability is included between 100 and 5000, for example, approximately 5000 for 99.8% pure iron, or even higher for purer iron.

[0095] Module cover 130 preferably has a sufficiently low surface and volume resistivity to form an EMI shield, for example, below 10 Ω·cm. 4 Surface resistivity in ohms per square.

[0096] The resistivity of the module cover 130 can depend on the electrically conductive particles in the molding material, as well as the geometry of the module cover, such as its length, width, and wall thickness. For example, to achieve a specified minimum level of EMI attenuation, the wall must contain sufficient conductive particles within the molding material forming the wall. Wall thickness, particle size, material, and fill factor are all factors that affect resistivity and are related to achieving the desired attenuation.

[0097] The effectiveness of EMI attenuation can also depend on the tooling design used for molded products. For example, if the tooling design has a gate location that allows for better flow of the composite molding material, EMI attenuation can be increased.

[0098] For example, electrically conductive particles include, but may not be limited to, one or more of the following:

[0099] - Carbon fiber;

[0100] - Short-cut carbon fibers;

[0101] - Electroplated carbon fiber, such as nickel-plated carbon fiber;

[0102] - Carbon nanotubes;

[0103] - Conductive carbon black particles;

[0104] - Stainless steel fiber.

[0105] The module cover 130 can be painted or electroplated, for example, a metal layer can be applied as a surface treatment layer to increase EMI protection.

[0106] The optical sensor module 100 also includes two cover glasses:

[0107] - A first cover glass 151 is positioned within the first opening 131 or between the first opening 131 and the light emitting device 112, and the first cover glass is adapted to transmit light signals emitted by the light emitting device; and

[0108] - A second cover glass 152 is positioned in the second opening 132 or between the second opening 132 and the light receiving sensor 122, and the second cover glass is adapted to transmit light signals reflected toward the light receiving sensor.

[0109] The first cover glass 151 preferably covers the first opening 131. The first cover glass 151 may be attached to the module cover 130. The first cover glass 151 may be positioned inside or outside the module cover 130 as shown in the figure. Similarly, the second cover glass 152 preferably covers the second opening 132. The second cover glass may be attached to the module cover 130. The second cover glass 152 may be positioned inside or outside the module cover 130 as shown in the figure.

[0110] The first cover glass and / or the second cover glass may include or consist of optical filters and / or one or more diffractive optical surfaces and / or refractive optical surfaces (e.g., but not limited to one or more lenses).

[0111] The cavity between the substrate and the module cover and the cover glass can be filled with a material that is transparent to light at the wavelength in use.

[0112] Each of the first cover glass 151 and the second cover glass 152 includes an electrically conductive trace 153 that can be embedded in the cover glass. Each of the first cover glass 151 and the second cover glass 152 also includes a second conductive pad 154, which is coupled to the end of the electrically conductive trace of the cover glass. In the following disclosure, the electrically conductive trace may be referred to as a “conductive trace” or a “trace”.

[0113] Conductive traces 153 in the first cover glass 151 and the second cover glass 152 allow EMI to be managed in the first opening 131 and the second opening 132 of the module cover 130, for example by providing EMI reflection in the first opening and the second opening.

[0114] In one variant, instead of having conductive traces in each of the first and second cover glasses, only one of the first and second glass glasses may have conductive traces.

[0115] In one variant, instead of having a first cover glass and a second cover glass, the module may have only one of the first cover glass and the second cover glass, preferably covering the light emitting device 112.

[0116] The conductive trace material can be one or more of the following materials: copper (Cu), aluminum (Al), tungsten (W), titanium (Ti), gold (Au), and indium tin oxide (ITO).

[0117] Each conductive trace in a conductive trace can be a fine and / or thin trace, for example, having a width of less than 1 micrometer and / or a thickness of less than 100 nanometers. The width and thickness of each conductive trace can be a trade-off between EMI protection functionality and the optical transmittance of the overlay glass. For example, conductive traces can be thicker or wider where the trace is unlikely to affect the desired quality of light transmission, and alternatively, traces can be thinner or narrower where the trace might affect the desired quality of light transmission.

[0118] The pitch and pattern of conductive traces can be determined based on the frequency of the EMI to be managed. For example, the higher the frequency, the smaller the pitch can be.

[0119] The spacing of the traces is, for example, smaller than the wavelength λ of the electromagnetic signal to be attenuated, and is, for example, a portion of the wavelength λ, where λ is equal to:

[0120]

[0121] Where v is the speed of light, and f is the frequency of the electromagnetic wave to be attenuated.

[0122] Different patterns of conduction traces can be imagined, such as Figure 2A and Figure 2B As shown in the diagram.

[0123] Figure 2A yes Figure 1A A top view of one of the cover glasses of the optical sensor module 100. Figure 2A For example, a first cover glass 151 is shown, but it can also be applied to a second cover glass 152. The conductive trace 153 of the illustrated cover glass 151 curves in a zigzag shape between two second conductive pads 154. This forms multiple substantially parallel linear portions 153A of the conductive trace, two parallel linear portions being separated by a distance D1 in one direction of the cover glass plan view. D1 is, for example, less than or equal to a portion of the wavelength λ, as defined above.

[0124] Figure 2BThis is a top view of another cover glass of an optical sensor module according to another embodiment. The conductive traces 253 of the illustrated cover glass 251 include portions forming a mesh or grid having two ends connected to a second conductive pad 154. This forms multiple substantially parallel linear portions 253A, 253B of the conductive traces in a first and second direction of the cover glass plan view, the first and second directions being substantially perpendicular to each other. Two parallel linear portions are separated by a distance D2 in the first direction and by a distance D3 in the second direction. D2 and D3 are, for example, less than or equal to a portion of the wavelength λ, as defined above.

[0125] Advantageously, at least one of the conductive traces is grounded in order to provide additional EMI protection, for example, through a second conductive pad 154.

[0126] The optical sensor module 100 also includes a plurality of conductive leads 135 assembled with the module cover 130, which in Figures 1A-1D The middle is represented as a lead frame. Conductive leads 135 are configured and positioned to electrically couple conductive traces 153 of the covering glass 151, 152 to the substrate 102.

[0127] Each lead frame 135 can be a single conductor, such as a single metal piece.

[0128] Each lead frame 135 can be inserted into a recess or channel 133 formed in the module cover 130.

[0129] In one variant, the lead frame can be overmolded during the injection molding operation used to form the module cover. The lead frame is then overmolded in the module cover.

[0130] Each leadframe 135 includes a first end 135A and a second end 135B, the first end being coupled (e.g., connected) to a first conductive pad 106 of a first conductive pad 106 on a substrate 102, and the second end being coupled (e.g., connected) to a second conductive pad 154 of a second conductive pad 154 on cover glass 151, 152. The first end 135A of each leadframe 135 may be coupled to the first conductive pad 106 via a conductive adhesive material 108 (e.g., conductive tape, paste, or glue) or via conductive solder. The second end 135B of each leadframe 135 may be coupled to the second conductive pad 154 via a conductive adhesive material 155 (e.g., conductive tape, paste, or glue), conductive solder, or via a conductive line 156 formed by wire bonding. Although Figure 1B and Figure 1D Conductive materials 155, such as conductive adhesives, are shown, but Figure 1A and Figure 1C Conductor line 156 is shown.

[0131] Examples of conductive lines are described in more detail in French patent application No. 2311572 entitled “Module de Capteur Optique”, filed on October 25, 2023, in the name of STMICROELECTRONICS INTERNATIONAL NV (law firm case number B22688), and in a European patent application claiming priority to French patent application No. 2311572, which are incorporated herein by reference to the fullest extent permitted by law.

[0132] The substrate 102 may include conductive rails (Figure 1- Figure 1D (Not shown in the diagram) The conductive traces are configured to be at a fixed voltage (such as ground) such that the conductive traces 153 in the cover glass 151, 152 can be coupled to this fixed voltage (such as ground) through some of the substrate 102 and lead frame 135, and for example through some of the first and second conductive pads. This can improve the EMI protection provided by the conductive traces 153.

[0133] The optical sensor module 100 may also include a common circuit system housed within the module cover 130. Figures 1A-1D (Not shown in the image).

[0134] Using such conductive molded covers provides significant EMI shielding for optical sensor modules. The use of molded covers allows for the formation of complex shapes with tight tolerances, and the insertion of conductive materials suitable for EMI shielding inside the molded cover eliminates the need for additional EMI shielding, such as metal shielding, on top of the optical sensor module, thereby avoiding an increase in the optical sensor module's footprint. The methods for fabricating the molded covers can be simple, such as using injection molding techniques.

[0135] Furthermore, in contrast to using, for example, metal shielding to reflect electromagnetic waves, the use of conductive materials suitable for EMI absorption allows electromagnetic waves to be absorbed, and thus the electromagnetic waves may lose energy that could interfere with other components.

[0136] The combination of conductive molding cover and conductive traces within the cover glass can provide large EMI shielding for optical sensor modules (including those in the openings of the module cover) by using absorption, reflection, and / or grounding to manage EMI.

[0137] By combining the cover glass with optical surfaces such as lenses and / or filters, optical sensor modules can additionally provide any optical functions, such as filtering, beamforming, and / or imaging, while reducing the total number of components in the module.

[0138] In one variant, the cover glass may not include conductive traces, and / or the optical sensor module may not include conductive leads.

[0139] Figure 3A This is a 3D view of the module cover of an optical sensor module 300 according to yet another embodiment. Figure 3B yes Figure 3A A cross-sectional view of the optical sensor module.

[0140] Sensor module 300 and Figure 1A The main difference in the optical sensor module 100 is that, instead of a lead frame having channels inserted into the module cover, the module cover 330 is formed with a conductive layer 335 on the surface of the module cover (e.g., the inner and bottom surfaces), thereby forming conductive leads on the module cover. The conductive layer 335 can be coated or plated onto the module cover, for example, using laser direct forming (LDS) technology.

[0141] Each conductive layer 335 includes a first end 335A and a second end 335B. The first end is coupled (e.g., connected) to a first conductive pad 106 of the substrate 102, and the second end is coupled (e.g., connected) to a second conductive pad 154 of the cover glass 151, 152. The first end 335A of each conductive layer 335 may be coupled to the first conductive pad 106 by a conductive adhesive material 108 (e.g., conductive tape, paste, or glue) or by conductive solder. The second end 335B of each conductive layer 335 may be coupled to the second conductive pad 154 by a conductive adhesive material 155 (e.g., conductive tape, paste, or glue) or by wire bonding.

[0142] Figure 3A and Figure 3B Other features of the optical sensor module 300 may be similar to Figures 1A to 1D Features of the optical sensor module 100.

[0143] Various embodiments and variations have been described. Those skilled in the art will understand that certain features of these embodiments can be combined, and other variations will readily conceive of by those skilled in the art.

[0144] Finally, based on the functional descriptions provided above, the actual implementation of the embodiments and variations described herein is within the capabilities of those skilled in the art.

Claims

1. An optical sensor module, characterized in that, include: Optical emitting equipment; Optical receiving sensor; A module cover, adapted to at least partially cover the light emitting device and the light receiving sensor, wherein the module cover is a molded cover; A substrate, assembled with the module cover, wherein the light emitting device is included in a first die mounted on the substrate, and the light receiving sensor is included in a second die mounted on the substrate; as well as Conductive leads are assembled with or included in the module cover, and the conductive leads are coupled to a first conductive pad on the substrate; as well as At least one cover glass covers at least one opening of the module cover, each cover glass including a conductive trace that provides electromagnetic interference shielding, the conductive trace being coupled to the conductive lead.

2. The optical sensor module according to claim 1, characterized in that, The molded cover is formed of a molding material comprising electrically conductive particles dispersed within the molding material to provide electromagnetic interference shielding.

3. The optical sensor module according to claim 2, characterized in that, The module cover is suitable for absorbing electromagnetic waves, and the module cover has a density of less than 10. 4 The surface resistivity is ohms / square, and the module cover has a relative permeability greater than 100.

4. The optical sensor module according to claim 2, characterized in that, The module cover is an injection-molded cover, and the molding material is resin, liquid crystal polymer, or another engineering plastic.

5. The optical sensor module according to claim 2, characterized in that, The electrically conductive particles include one or more of the following: Carbon fiber; Short-cut carbon fibers; Electroplated carbon fiber, such as nickel-plated carbon fiber; Carbon nanotubes; Conductive carbon black particles; and Stainless steel fiber.

6. The optical sensor module according to claim 1, characterized in that, The module cover includes a metal surface treatment layer for increased electromagnetic interference shielding.

7. The optical sensor module according to claim 1, characterized in that, The module cover includes a partition wall adapted to separate the light emitting device and the light receiving sensor.

8. The optical sensor module according to claim 1, characterized in that, The conductive lead is coupled to the first conductive pad of the substrate using a conductive adhesive material, or the substrate includes a conductive rail configured to be at a fixed voltage such as ground, and the conductive rail is coupled to the first conductive pad.

9. The optical sensor module according to claim 1, characterized in that, The conductive leads are either inserted into channels in the module cover or are molded lead frames encased in the module cover.

10. The optical sensor module according to claim 1, characterized in that, The conductive leads are conductive layers formed on the surface of the module cover, such as by direct forming laser technology.

11. The optical sensor module according to claim 1, characterized in that, The at least one opening includes a first opening located above the light emitting device and a second opening located above the light receiving sensor; And the at least one covering glass comprises: A first cover glass is positioned in the first opening or between the first opening and the light emitting device, and the first cover glass is adapted to transmit light signals emitted by the light emitting device; as well as A second cover glass is positioned in the second opening or between the second opening and the light receiving sensor, and the second cover glass is adapted to transmit light signals reflected toward the light receiving sensor.

12. The optical sensor module according to claim 11, characterized in that, The first cover glass and the second cover glass each include conductive traces that provide electromagnetic interference shielding.

13. The optical sensor module according to claim 1, characterized in that, Each cover glass also includes a second conductive pad coupled to the conductive trace, the conductive lead being coupled to the second conductive pad using a conductive adhesive material.

14. The optical sensor module according to claim 1, characterized in that, The conduction trace includes substantially linear portions that are parallel to each other and spaced apart by a distance less than or equal to a portion of the wavelength of the electromagnetic signal to be attenuated.

15. The optical sensor module according to claim 1, characterized in that, Conductive trace materials include one or more of the following: copper, aluminum, tungsten, titanium, gold, and indium tin oxide.

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