Optical sensor module

Abstract

The invention 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-REFERENCE TO RELATED APPLICATION(S)

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

[0003] The present disclosure relates generally to optical sensors, and more particularly to optical sensor modules. Background Art

[0004] Optical sensors such as proximity sensors can be used to detect the presence of nearby objects. Optical sensors are able to do so without physically contacting the object. Some types of optical sensors, such as those used in optical ranging devices or time-of-flight sensors, can be used to determine the actual distance to such nearby objects. Optical sensors can be used in various electronic devices, such as cameras, phones (including smartphones), smart watches, tablets, vehicles, machinery, and other devices for detecting the presence of nearby objects and / or the distance to nearby 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] An optical sensor generally includes components such as a light emitting device, a light receiving sensor, and a processing device generally for processing signals received from the light receiving sensor. The components of the optical sensor may be formed on a substrate, and a cover may be bonded to the substrate over the components, for example to protect them from damage, thereby forming an optical sensor module, also referred to as an optical sensor package. The cover is generally formed with a first opening located above the light emitting device and a second opening located above the light receiving sensor.

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

[0007] There is a need for improvements in optical sensor modules, particularly to address electromagnetic interference (EMI) issues between the optical sensor module and another electronic device (eg, an electronic device containing the optical sensor module). Summary of the invention

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

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

[0010] - Light emitting equipment;

[0011] - a light receiving sensor; and

[0012] - 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 formed of a molding material including electrically conductive particles dispersed therein for providing electromagnetic interference shielding.

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

[0014] - Light emitting equipment;

[0015] - light receiving sensor;

[0016] - 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;

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

[0018] - a conductive lead assembled with or included in the module cover, and the conductive lead is coupled to a first conductive pad of the substrate; and

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

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

[0021] In one embodiment, the module cover is suitable for absorbing electromagnetic waves and / or has a 4 ohms / square, and / or have a relative magnetic 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 engineered plastic.

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

[0024] - Carbon fiber;

[0025] - Chopped carbon fiber;

[0026] - Electroplated carbon fiber, such as nickel (Ni) plated 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 increased 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 the module cover, 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.

[0033] In one embodiment, the module also includes a conductive lead assembled with the module cover or included in the module cover, and the conductive lead is coupled to a first conductive pad of a substrate, for example using a conductive adhesive material, and the substrate includes a conductive rail configured to be at a fixed voltage such as ground, the conductive rail being coupled to at least one of the first conductive pads, for example.

[0034] In one embodiment, the conductive leads are lead frames that are inserted into channels of the module cover or overmolded in the module cover.

[0035] In one embodiment, the conductive leads are a conductive layer formed on the surface of the module lid, such as by direct structuring laser technology.

[0036] In one embodiment, the module cover includes a first opening located above the light emitting device and a second opening located 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 a light signal emitted by the light emitting device; and

[0038] 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 the light signal reflected toward the light receiving sensor.

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

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

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

[0042] In an embodiment, the first cover glass and / or the second cover glass further comprises at least one second conductive pad coupled to the conductive trace, at least one of the conductive leads being coupled to the at least one second conductive pad, for example using a conductive adhesive material.

[0043] In an embodiment, the conductive trace comprises substantially linear portions which are parallel to each other and are separated from each other by a distance which is less than or equal to a fraction of the wavelength of the electromagnetic signal to be attenuated.

[0044] In an embodiment, the conductive trace material includes one or more of the following materials: copper, aluminum, tungsten, titanium, gold, indium tin oxide. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The foregoing features and advantages, as well as others, will be further described in detail in the following description of specific embodiments given by way of illustration and not limitation with reference to the accompanying drawings, in which:

[0046] Figure 1A is a 3-dimensional view of an optical sensor module according to an embodiment;

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

[0048] Figure 1C yes Figure 1A A top view of an optical sensor module;

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

[0050] Figure 2A yes Figure 1A A top view of a cover glass of an optical sensor module;

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

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

[0053] Figure 3B yes Figure 3A Cross-sectional view of an optical sensor module. DETAILED DESCRIPTION

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

[0055] For the sake of 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 described in detail, and the embodiments are compatible with conventional optical sensors. For example, a light emitting device, a light receiving sensor, and other components of the optical sensor (such as a processing device) are not described in detail. Similarly, not all components of the optical sensor module are described in detail, and the embodiments are compatible with conventional optical sensor modules.

[0056] Unless otherwise indicated, when referring to two elements being connected together, this means a direct connection without any intermediate elements except conductors, and when referring to two elements being coupled together, this means the two elements may be connected or they may 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 referring to relative position qualifiers, such as the terms "above", "below", "higher than", "lower than", etc., or referring to qualifiers of orientation, such as "horizontal", "vertical", etc., reference is made to the orientation shown in the figures, or to the optical sensor module as oriented during normal use.

[0058] Unless otherwise stated, the expressions "about", "approximately", "substantially" and "approximately" mean within 10%, and preferably within 5%.

[0059] In the following disclosure, unless otherwise indicated, when referring to resistivity, reference is made to electrical resistivity. Similarly when referring to a conductive element, reference is made to an electrically conductive element.

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

[0061] Embodiments relate to optical sensor modules. 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 a processing device for processing signals received from the light receiving sensor. The light emitting device and the light receiving sensor can be formed on a substrate, such as each in a different die attached to the substrate, and a cover can be bonded to the substrate over the light emitting device and the light receiving sensor, thereby forming an optical sensor module, also referred to as an optical sensor package. The cover is generally formed with a first opening located above the light emitting device and a second opening located above the light receiving sensor.

[0062] The optical sensor module may be affected by electromagnetic interference (EMI) with another electronic device.

[0063] For example, when the 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 phone (e.g., a smartphone), a smart watch, a tablet, a vehicle, a machine, or another device for which detecting the presence of and / or the distance to a nearby object may be useful.

[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] Furthermore, the environment, such as an environment with huge electromagnetic waves, such as a data center, may also interfere with the components of the optical sensor module and affect its performance.

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

[0069] The metal of the metal shield is preferably chosen to be:

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

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

[0072] The metal shield may be grounded to further improve the effectiveness of EMI protection, for example for efficient absorption of electric fields.

[0073] However, the metal shield may have a number of disadvantages, for example it may increase the footprint of the optical sensor module. Depending on the method used, the manufacture of the metal shield may introduce a large number of steps and / or incur high production costs, may require large tolerances (which may be problematic for small optical sensor modules, for example) and / or may inefficiently form complex shapes. The manufacture may also introduce gaps in the metal shield that may allow electromagnetic waves to pass through. The choice of materials for the metal shield may also be limited. Furthermore, it may be difficult to implement a grounding scheme on the metal shield.

[0074] In addition to the possible disadvantages mentioned above, another problem is that the opening in the optical sensor module involves having an opening in the metal shielding, which is then not shielded, which can allow 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 comprised between 1 and 5 mm, or even between 0.1 and 5 mm. However, for certain frequencies, such as frequencies 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 can overcome all or part of the above-mentioned disadvantages, especially solve the electromagnetic interference problem, use a simple solution, which can avoid increasing the occupied space of the optical sensor module and avoiding complicating the manufacturing method, and it can form complex shapes with small tolerances.

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

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

[0078] Figure 1Ais a 3-dimensional view of an optical sensor module 100 according to an embodiment. Figure 1B yes Figure 1A Exploded 3D view of the optical sensor module. Figure 1B The exploded view of FIG. 1 makes it easier to see the different components of the optical sensor module 100 . Figure 1C yes Figure 1A 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 can be seen in Figure 1A and Figure 1C Seen in.

[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 a plurality of photodiodes), which are formed above the 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 , and 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., through first conductive wires 141 and second conductive wires 142, respectively). For example, a first end of each first conductive wire (respectively, second conductive wire) is coupled to a conductive pad ( Figure 1A-Figure 1D ), and the second end of each first conductive line (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 fixed to the substrate 102, such as by an adhesive material or solder. The adhesive material can be any material suitable for fixing the die to the substrate, such as tape, paste, glue ( Figure 1A-Figure 1D not shown).

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

[0085] Generally, the optical sensor module 100 includes a processing device ( Figure 1A-Figure 1D 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 , for example, at or close to an edge of the substrate.

[0087] A module cover 130 having a first opening 131 and a second opening 132 is attached or bonded to the 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 opening and the second opening do not cover the first die and the second die. The module cover 130 may be substantially opaque to light at the wavelength used.

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

[0089] The first opening and the second opening 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 restrictive, 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 for substantially preventing 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 cavity having one of a first opening and a second opening.

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

[0092] The module cover 130 may be formed using an injection molding method.

[0093] For example, a molding material comprising electrically conductive particles is suitable for absorbing electromagnetic waves (EMI absorption).

[0094] For example, a molding material comprising electrically conductive particles has a high magnetic permeability. Typically, the relative magnetic permeability of the molding material may be higher than 100, although the higher the better for EMI attenuation. For reference, a high magnetic permeability material is iron (99,8% purity), whose relative magnetic permeability is comprised between 100 and 5000, for example equal to about 5000 for 99,8% pure iron, or higher for purer iron.

[0095] The module cover 130 preferably has a surface and volume resistivity low enough to provide EMI shielding, such as less than 10 4 Surface resistivity in ohms / square.

[0096] The resistivity of the module cover 130 may depend on the electrically conductive particles in the molding material, and may also depend on the geometry of the module cover, such as the length, width, and wall thickness of the module cover. For example, to obtain 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 relevant to achieving the desired attenuation.

[0097] EMI attenuation effectiveness can also depend on the tool design used to mold the product. For example, if the tool design has a gate location that allows the composite molding material to flow better, EMI attenuation can be increased.

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

[0099] - Carbon fiber;

[0100] - Chopped carbon fiber;

[0101] - electroplated carbon fibers, such as nickel-plated carbon fibers;

[0102] - carbon nanotubes;

[0103] - conductive carbon black particles;

[0104] -Stainless steel fiber.

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

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

[0107] a first cover glass 151 positioned in the first opening 131 or between the first opening 131 and the light emitting device 112 and adapted to transmit a light signal 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 is adapted to transmit the light signal reflected toward the light receiving sensor.

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

[0110] The first cover glass and / or the second cover glass may include or consist of an optical filter and / or a single or multiple diffractive optical surface and / or a refractive optical surface (eg, but not limited to, a single or multiple lenses).

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

[0112] Each of the first cover glass 151 and the second cover glass 152 includes an electrically conductive trace 153 that may 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 that is each coupled to an 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] The conductive traces 153 in the first cover glass 151 and the second cover glass 152 allow for managing EMI in the first opening 131 and the second opening 132 , respectively, of the module cover 130 , for example by providing EMI reflection in the first opening and the second opening.

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

[0115] In a 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 may be one or more of the following materials: copper (Cu), aluminum (Al), tungsten (W), titanium (Ti), gold (Au), indium tin oxide (ITO).

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

[0118] The pitch and pattern of the 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 fraction 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 chosen to be attenuated.

[0122] Different patterns of conductive traces can be envisioned, such as Figure 2A and Figure 2B As shown in the figure.

[0123] Figure 2A yes Figure 1A FIG. 1 is 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 is bent in a zigzag shape between two second conductive pads 154. This forms a plurality of 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 plane. D1 is, for example, less than or equal to a portion of the wavelength λ, as defined above.

[0124] Figure 2B1 is a top view of another cover glass for an optical sensor module according to another embodiment. The conductive trace 253 of the illustrated cover glass 251 includes several portions forming a mesh, or grid, having two ends connected to the second conductive pad 154. This forms a plurality of substantially parallel linear portions 253A, 253B of the conductive trace in a first direction and a second direction in the plan view of the cover glass, the first direction and the second direction being substantially perpendicular to each other. The 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 fraction of the wavelength λ, as defined above.

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

[0126] The optical sensor module 100 also includes a plurality of conductive leads 135 assembled with the module cover 130. Figure 1A-Figure 1D The conductive leads 135 are configured and positioned so as to electrically couple the conductive traces 153 of the cover glasses 151 , 152 to the substrate 102 .

[0127] Each lead frame 135 may be a single conductive member, such as a single metal member.

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

[0129] In a variation, the lead frame may be overmolded during an injection molding operation used to form the module lid.The lead frame is then overmolded in the module lid.

[0130] Each lead frame 135 includes a first end 135A coupled (e.g., connected) to one of the first conductive pads 106 of the substrate 102 and a second end 135B coupled (e.g., connected) to one of the second conductive pads 154 of the cover glass 151, 152. The first end 135A of each lead frame 135 may be coupled to the first conductive pad 106 by a conductive adhesive material 108 (e.g., a conductive tape, paste, or glue) or by a conductive solder. The second end 135B of each lead frame 135 may be coupled to the second conductive pad 154 by a conductive adhesive material 155 (e.g., a conductive tape, paste, or glue), a conductive solder, or by a conductive wire 156 formed by wire bonding. Although Figure 1B and Figure 1D A conductive material 155 such as a conductive glue is shown, but Figure 1A and Figure 1C Conductive 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 the European patent application claiming priority from French patent application No. 2311572, which are incorporated herein by reference to the maximum extent permitted by law.

[0132] The substrate 102 may include conductive tracks (FIG. 1- Figure 1D ), the conductive track is configured to be at a fixed voltage (such as ground) so that the conductive trace 153 in the cover glass 151, 152 can be coupled to the fixed voltage (such as ground) through some of the substrate 102 and the lead frame 135 and, for example, through some of the first conductive pad and the second conductive pad. This can improve the EMI protection provided by the conductive trace 153.

[0133] The optical sensor module 100 may also include a common circuit system ( Figure 1A-Figure 1D not shown).

[0134] The use of such a conductive molded cover provides significant EMI shielding for the optical sensor module. The use of a molded cover allows complex shapes to be formed with tight tolerances, and inserting a conductive material suitable for EMI shielding inside the molded cover eliminates the need to add EMI shielding such as a metal shield above the optical sensor module, thereby avoiding expanding the footprint of the optical sensor module. The method of making the molded cover can be simple, such as using injection molding techniques.

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

[0136] The combination of the conductive molded cover and the conductive traces within the cover glass can provide great EMI shielding for the optical sensor module (including in the opening of the module cover) using absorption, reflection and / or grounding to manage EMI.

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

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

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

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

[0141] Each conductive layer 335 includes a first end 335A coupled (e.g., connected) to one of the first conductive pads 106 of the substrate 102 and a second end 335B coupled (e.g., connected) to one of the second conductive pads 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., a conductive tape, paste, or glue) or by a 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., a conductive tape, paste, or glue) or by a wire bond.

[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 appreciate that certain features of these embodiments may be combined, and those skilled in the art will readily conceive of other variations.

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

Claims

1. An optical sensor module, comprising: Light emitting equipment; Light receiving sensor; 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; a substrate assembled with the module cover, the light emitting device being included in a first die mounted on the substrate, and the light receiving sensor being included in a second die mounted on the substrate; as well as a conductive lead assembled with or included in the module cover, and the conductive lead is coupled to a first conductive pad of the substrate; as well as At least one cover glass covers the at least one opening of the module cover, each cover glass includes a conductive trace providing electromagnetic interference shielding, the conductive trace being coupled to the conductive lead.

2. The optical sensor module according to claim 1, wherein: The molded cover is formed of a molding material including electrically conductive particles dispersed therein for providing electromagnetic interference shielding.

3. The optical sensor module according to claim 2, wherein: The module cover is suitable for absorbing electromagnetic waves, and the module cover has a 4 The surface resistivity is ohm / square, and the module cover has a relative magnetic permeability higher than 100.

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

5. The optical sensor module according to claim 2, wherein: The electrically conductive particles include one or more of the following: Carbon fiber; Chopped carbon fiber; 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, wherein: The module cover includes a metal surface treatment layer for increased electromagnetic interference shielding.

7. The optical sensor module according to claim 1, wherein: 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, wherein: The conductive lead is coupled to the first conductive pad of the substrate using a conductive adhesive material, or the substrate includes a conductive track configured to be at a fixed voltage, such as ground, which is coupled to the first conductive pad.

9. The optical sensor module according to claim 1, wherein: The conductive leads are lead frames inserted into channels of the module cover or overmolded in the module cover.

10. The optical sensor module according to claim 1, wherein: The conductive leads are a conductive layer formed on the surface of the module cover, such as by direct structuring laser technology.

11. The optical sensor module according to claim 1, wherein: 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 cover glass comprises: 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 an optical signal 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 a light signal reflected toward the light receiving sensor.

12. The optical sensor module according to claim 11, wherein: 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, wherein: 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, wherein: The conductive traces include substantially linear portions that are parallel to each other and separated from each other by a distance that is less than or equal to a fraction of a wavelength of an electromagnetic signal to be attenuated.

15. The optical sensor module according to claim 1, wherein: The conductive trace materials include one or more of: copper, aluminum, tungsten, titanium, gold, and indium tin oxide.

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