Optical sensor module

Abstract

The present disclosure provides an optical sensor module. An example optical sensor module includes a light emitting device, a module cover, at least one conductive strip, glass, and at least one conductive wire; the module cover is suitable for at least partially covering the light emitting device, and the module cover comprises a first opening located above the light emitting device; at least one conductive strip is assembled with the module cover or included in the module cover; a glass positioned in and / or covering the first opening and adapted to transmit an optical signal emitted by the light emitting device, the glass comprising a conductive trace; at least one conductive wire is formed by wire bonding, the at least one conductive wire electrically connecting the conductive trace to the at least one conductive strip.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to French patent application No. 2311572, 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, tablet computers, 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, transmitting an alarm signal, coupling or decoupling electrical communications, or any other desired function.

[0005] An optical sensor typically includes components such as a light emitting device, a light receiving sensor (or image 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 the components 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 over the light emitting device and a second opening over the light receiving sensor.

[0006] Generally described, the light emitting device emits a light signal or light beam through a first opening. If an object is outside 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 neighboring object and / or a distance to a neighboring object.

[0007] The light emitting device for generating the light beam is generally covered by glass to protect the device from dust, the glass being relatively transparent to light at the wavelength used. A first opening located above the light emitting device may be covered by glass. The glass may also be used as a diffuser suitable for reducing the intensity of the emitted light beam to a certain extent, for example for safety reasons, such as protecting the user. However, if the glass is detached, broken or otherwise removed from above the light emitting device, the intensity of the light emitting device may be such that it may cause a risk of injury, such as injury to the user's eyes.

[0008] There exists a need for improved optical sensor modules, particularly to address the above mentioned safety issues relating to light emitting devices.

[0009] There may also be a need to manage electromagnetic interference (EMI) between the optical sensor module and another electronic device, especially through the opening of the cover. Summary of the invention

[0010] One embodiment addresses all or some of the disadvantages of known optical sensor modules.

[0011] One embodiment provides an optical sensor module, the optical sensor module comprising:

[0012] - light emitting device;

[0013] - a module cover adapted to at least partially cover the light emitting device, the module cover comprising a first opening located above the light emitting device;

[0014] - at least one conductive strip assembled with or included in the module cover;

[0015] - glass positioned in the first opening or between the first opening and the light emitting device, and / or the glass covers the first opening, and the glass is adapted to transmit the optical signal emitted by the light emitting device, the glass comprising conductive traces; and

[0016] - At least one conductive line formed by wire bonding, the at least one conductive line electrically connecting the conductive trace to the at least one conductive strip.

[0017] In one embodiment, the material of each conductive line includes one or more of the following materials: gold, copper, aluminum, silver or tin alloy.

[0018] In an embodiment, the at least one conductive line is configured to have a flexibility suitable for absorbing dimensional variations between the glass, the module cover, and the at least one conductive strip.

[0019] In an embodiment, at least one conductive line has a thickness less than or equal to 40 μm, such as a thickness less than or equal to 20 μm, and / or a length less than or equal to 2 mm.

[0020] In an embodiment, the module further comprises a substrate assembled with the module cover, the at least one conductive strip being coupled to at least the first conductive pad of the substrate, for example using a conductive adhesive material.

[0021] In an embodiment, the substrate includes a conductive track (eg, ground) configured to be at a fixed voltage, the conductive track being coupled to one of the at least one first conductive pads.

[0022] In an embodiment, the glass further comprises at least a second conductive pad coupled to the conductive trace, for example the at least one second conductive pad is connected to an end of the conductive trace, the at least one conductive strip being coupled to the at least one second conductive pad using the at least one conductive line.

[0023] In an embodiment, the at least one conductive line and / or a bond of the at least one conductive line is arranged to break in case the glass becomes detached from the module cover.

[0024] In one embodiment, the module further comprises a detection circuit adapted to detect when a conductive loop formed by at least one conductive strip, at least one conductive line and a conductive trace is broken, the detection circuit being configured to deactivate the light emitting device if the detection circuit detects an open circuit in the conductive loop.

[0025] In an embodiment, the conductive traces provide electromagnetic interference shielding.

[0026] In an embodiment, at least one conductive strip is inserted into at least one channel of the module cover.

[0027] In an embodiment, the at least one conductive strip is at least one conductive lead, such as at least one lead frame.

[0028] In an embodiment, the at least one conductive strip is at least one connecting flex overmolded in the module cover.

[0029] In an embodiment, the glass is a lens, or a lens pad, the glass for example comprising at least a beam former.

[0030] In one embodiment, the module cover:

[0031] - is an injection molded cover, the molding material being, for example, a resin; and / or

[0032] - is a plastic module cover; and / or

[0033] - Includes materials suitable for providing electromagnetic interference shielding.

[0034] In one embodiment, the module further comprises:

[0035] a light receiving sensor at least partially covered by the module cover, the module cover comprising a second opening above the light receiving sensor; and

[0036] - a filter in or covering the second opening and adapted to transmit the reflected light signal towards the light receiving sensor; the filter for example comprises a second conductive trace providing electromagnetic interference shielding. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] 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 and not limitation with reference to the accompanying drawings, in which:

[0038] Figure 1 is a 3-dimensional view of an optical sensor module according to an embodiment;

[0039] Figure 2A and Figure 2B yes Figure 1 a 3-dimensional view of a module cover of an optical sensor module; and

[0040] Figure 3A , Figure 3B , Figure 3C and Figure 3D It is a graphic form Figure 1 3-dimensional view and top view of the optical sensor module. DETAILED DESCRIPTION

[0041] The same features have been designated by the same reference numerals in the various figures. In particular, common structural and / or functional features among the various embodiments may have the same reference numerals and may be provided with the same structure, dimensions and material properties.

[0042] 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, the light emitting device, the light receiving sensor, and other components of the optical sensor (such as the 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.

[0043] 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.

[0044] 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", "lower", 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.

[0045] Unless otherwise stated, the expressions "about," "approximately," "substantially," and "on the order of" mean within 10%, and preferably within 5%.

[0046] In the following disclosure, unless otherwise indicated, when reference is made to glass, this includes elements made of materials that are relatively transparent to light at the wavelengths used, e.g., having a transmittance of 90% or more for those wavelengths. This includes, but is not limited to, glass materials or plastic materials. Glass may be formed from a solid single material, or may be formed by assembling multiple materials, in which case only portions of the glass may be in the transparent material. Glass may include or consist of a lens or multiple lenses and / or an optical filter.

[0047] In the following disclosure, unless otherwise indicated, when referring to a filter, referring to an optical filter.

[0048] In the following disclosure, unless otherwise indicated, when referring to a conductive element such as a conductive trace, pad, strip, or lead, reference is made to an electrically conductive element.

[0049] 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, such as a combination of at least two of the above modules or other functions, such as a combination of a proximity detector module with a floodlight and / or a dot projector.

[0050] Embodiments relate to optical sensor modules. An optical sensor typically includes a light emitting device and a light receiving sensor, the light emitting device including, for example, a light emitting diode (LED) and / or a laser such as a vertical cavity surface emitting laser (VCSEL), and the light receiving sensor including, for example, a photodiode or multiple photodiodes. The optical sensor generally also includes a processing device for processing a signal received from the light receiving sensor. The light emitting device and the light receiving sensor may be formed on a substrate, and a cover may 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.

[0051] As explained in the background section above, the light emitting device for generating the light beam is generally covered by glass, which is used to protect the device, for example, from dust, and the glass is relatively transparent to light at the wavelength used. The glass can cover the first opening. The glass can also be used as a diffuser suitable for reducing the intensity of the emitted light beam to a certain extent, for example for safety reasons, such as protecting the user. However, if the glass is detached from, broken or otherwise removed from above the light emitting device, the light emitting device will no longer be covered, thereby exposing the user to the full intensity of the light beam.

[0052] In order to address this safety issue involving the light emitting device, the glass may include a conductive trace above the light emitting device. Generally, the conductive trace is arranged to be coupled to a conductive rail configured to be at a fixed voltage, which is generally connected to or included in the substrate. This can be accomplished by one or more conductive elements in the cover, for example by one or more lead frames. In such a case, a coupling between the conductive element(s) in the cover and the conductive trace is provided. One solution is to use a conductive glue between the conductive trace and the conductive element(s). However, the coupling using a conductive glue may be subject to dimensional changes between the glass and the cover, which may be due to different coefficients of thermal expansion (CTE), and there is a risk of breakage.

[0053] The inventors have proposed an optical sensor module making it possible to overcome all or part of the above-mentioned disadvantages, in particular to improve the coupling between the substrate and the conductive traces in the glass, for example the coupling between the conductive element(s) in the cover bonded to the substrate and the conductive traces. It is expected that this solution is suitable for solving safety problems related to light emitting devices.

[0054] 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.

[0055] Figure 1is a 3-dimensional view of an optical sensor module according to an embodiment.

[0056] The optical sensor module 100 includes a light emitting device 110, for example, including an LED such as an infrared LED and / or a laser such as a VCSEL, and a light receiving sensor 120 or an image sensor, for example, including a photodiode such as (one or more) SPAD or a plurality of photodiodes. The light emitting device 110 and the light receiving sensor 120 are mounted above the substrate 102.

[0057] The substrate 102 may be a printed circuit board (PCB).

[0058] The light emitting device 110 is configured to emit a light signal at a specific frequency or frequency range, and the light receiving sensor 120 is adapted to detect the emitted light signal that is returned (e.g., reflected by an object). In one embodiment, the light emitting device 110 is configured to emit an infrared (IR) light signal, and the light receiving sensor 120 is adapted to detect the IR light signal that is returned (e.g., reflected by an object).

[0059] Figure 1 The light emitting device 110 includes a first light source 111 and a second light source 112, each of which is mounted on a first intermediary layer 141 and a second intermediary layer 142, respectively, and the first intermediary layer 141 and the second intermediary layer 142 are mounted on the top surface 102A of the substrate 102. The first light source 111 and the second light source 112 are, for example, a first VCSEL and a second VCSEL. In a variant, the light source can be mounted on the substrate without an intermediary layer.

[0060] In a variant, the light emitting device may comprise only one light source, such as a VCSEL, for example mounted on an interposer.

[0061] The light emitting device 110 may be electrically coupled to the light receiving sensor 120 , for example, through the substrate 102 .

[0062] The top surface 102A of the substrate 102 includes first conductive pads 106, which are located, for example, at the edge of the substrate, or close to the edge of the substrate (not at the Figure 1 shown in Figure 3A ).

[0063] The optical sensor module 100 includes a laser driver 144 configured to control the first light source 111 and the second light source 112. The laser driver 144 may be located in the same cavity as the light emitting device 110, as described below. This is not limiting and other configurations may be envisioned by those skilled in the art.

[0064] The optical sensor module 100 may include a processing circuit (not shown). Figure 1 ), the processing circuit may be configured to process the optical signal emitted by the light emitting device 110 and received by the light receiving sensor 120. The processing circuit may be mounted on the top surface 102A of the substrate 102.

[0065] The optical sensor module 100 includes other electronic circuits or components, such as surface mount technology (SMT) components 145 that are also mounted on the top surface 102A of the substrate 102. The SMT components 145 may include resistors. Other SMT components may include capacitors.

[0066] The light receiving sensor 120 can be coupled to the substrate 102 using a conductive connector (e.g., a conductive wire), and / or 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 light receiving sensor 120 to the substrate, such as tape, paste, glue.

[0067] The module cover 130 having the first opening 131 and the second opening 132 is attached or bonded to the substrate 102 and is adapted to at least partially surround or cover the components mounted on the substrate 102, at least the light emitting device 110, the light receiving sensor 120, the interposer 141, 142, the laser driver 144 and the SMT component 145. At least partially means that all components may not be covered, for example, the first opening and the second opening do not cover the components under the opening. The module cover 130 may be substantially opaque to light at the wavelength used.

[0068] For example, the module cover 130 is mounted on the opaque adhesive 104 positioned on the substrate 102 .

[0069] The first opening and the second opening are located at the top side 130A of the module cover 130. The first opening 131 is located above the light emitting device 110 and the second opening 132 is located above the light receiving sensor 120. 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.

[0070] The module cover 130 may include a partition wall 133 between the light emitting device 110 and the light receiving sensor 120. The partition wall 133 may form an optical isolator for substantially preventing internal propagation of a light beam between the light emitting device 110 and the light receiving sensor 120 within the module cover 130. For example, the partition wall 133 defines a first cavity 136 and a second cavity 137, the first cavity 136 including a first opening 131 above the light emitting device 110, and the second cavity 137 including a second opening 132 above the light receiving sensor 120. The laser driver 144 may be located in the first cavity 136 together with the light emitting device 110, as indicated above.

[0071] The module cover 130 may be a plastic cover and / or a molded cover formed of a molding material such as resin, liquid crystal polymer (LCP), nylon, or another engineering plastic. The module cover 130 may be formed using an injection method.

[0072] The optical sensor module 100 further includes:

[0073] a glass 150 positioned in the first opening 131 or between the first opening 131 and the light emitting device 110 and adapted to transmit the optical signal emitted by the light emitting device; and

[0074] A filter 160 , which is positioned in the second opening 132 or between the second opening 132 and the light receiving sensor 120 and which is adapted to transmit the light signal reflected toward the light receiving sensor.

[0075] The glass 150 preferably covers the first opening 131. The glass 150 is preferably attached to the module cover 130. For example, the glass 150 is on a mount 139 formed in the first opening 131, and the glass is mounted outside the module cover 130. In a variation, the glass may be mounted inside the module cover.

[0076] Similarly, the filter 160 preferably covers the second opening 132. The filter 160 is preferably attached to the module cover 130. For example, the filter 160 is positioned inside the module cover 130. In a variation, the filter may be mounted outside the module cover.

[0077] The glass 150 may include two optical surfaces which may be two beam shapers 151A, 151B, a first beam shaper 151A being located above the first light source 111 and a second beam shaper 151B being located above the second light source 112. The glass 150 may be a lens or a lens pad.

[0078] The optical sensor module 100 may further include a second lens 162 between the filter 160 and the light receiving sensor 120 .

[0079] The glass 150 includes a conductive trace 152, which may be embedded in the glass. The glass 150 also includes a second conductive pad 154 coupled to the conductive trace 152, such as two second conductive pads, one at each end of the conductive trace.

[0080] Conductive traces may be referred to as “traces” in the following disclosure. Conductive pads may be referred to as “pads” in the following disclosure.

[0081] The second pad 154 and the trace 152 of the glass 150 can be implemented with the same conductive coating, for example, formed using a photolithography process. An example of a process flow for forming the second pad 154 and the trace 152 of the glass 150 is:

[0082] - Subtractive process, which is carried out in the following order: metal deposition, photolithography, etching and stripping;

[0083] - additive process or lift-off, i.e. the following sequence: photolithography, metal deposition and lift-off; or

[0084] - Micromolding, i.e. in the following sequence: metal deposition, photolithography, electrodeposition, lift-off and etching.

[0085] The conductive traces 152 of the glass 150 may be used in safety functions involving light emitting devices.

[0086] In a variation, the filter 160 may also include a second conductive trace, which may also serve as protection against electromagnetic interference in the second opening 132 of the module cover 130, for example by providing EMI reflection in the second opening.

[0087] The conductive trace material may be one or more of the following: copper (Cu), aluminum (Al), tungsten (W), titanium (Ti), gold (Au), indium tin oxide (ITO), or another metal or metal alloy.

[0088] The conductive traces may be fine and / or thin traces, for example having a width of less than 1 micron and / or a thickness of less than 100 nanometers, without being limited to these values. The width and thickness of each conductive trace may be a compromise between the safety function and the optical transmittance of the glass. For example, the traces may be wider and / or thicker where the traces are less likely to limit light transmission, and may be finer and / or thinner where the traces are likely to limit light transmission.

[0089] The optical sensor module 100 also includes two conductive leads 134 assembled to the module cover 130. The conductive leads 134 are configured and positioned so as to electrically couple the conductive traces 152 of the glass 150 to the substrate 102. The conductive leads 134 are, for example, lead frames.

[0090] Each conductive lead 134 may be a single conductive piece, such as a single metal piece.

[0091] Each conductive lead 134 may be inserted into a conductive portion formed in the module cover 130 (at Figure 2A and Figure 2B ) in a recess or channel 135 therein.

[0092] In a variation, the conductive leads may be overmolded during an injection molding operation used to form the module cover.The conductive leads are then overmolded in the module cover.

[0093] Each conductive lead 134 includes a first end 134A coupled (e.g., connected) to the substrate 102 via one of the first conductive pads 106 and a second end 134B coupled (e.g., connected) to the conductive trace 152 via one of the second conductive pads 154. The first end 134A of each conductive lead 134 may be bonded to the substrate 102 via a conductive adhesive material 108 (e.g., conductive tape, paste, or glue, or conductive solder (not shown). Figure 1 shown in Figure 3A ) is coupled to one of the first conductive pads 106 .

[0094] The second end 134B of each conductive lead 134 is coupled to a second conductive pad 154 through a conductive line 155 formed by a wire bond, which may be referred to as a “wire bond”.

[0095] Thus, through the second conductive pad 154 , the conductive lead 134 is coupled to the conductive trace 152 using a wire bond 155 .

[0096] The conductive wire 155 is preferably flexible enough, for example to absorb dimensional variations between the glass 150, the module cover 130 and the conductive lead 134, which may be due to different coefficients of thermal expansion (CTE). In fact, the key function of the conductive wire 155 is to provide a flexible connection between the conductive lead 134 and the module cover 130, in particular between the conductive lead 134 and the second conductive pad 154 on the glass 150. However, one of the main parameters that has an impact on flexibility is the diameter of the conductive wire. More precisely, the smaller the diameter, the greater the flexibility.

[0097] For example, the conductive line 155 has a thickness comprised between 20 and 40 μm or even less than 20 μm.

[0098] The conductive wire 155 may have a length of about 2 mm, or less than 2 mm.

[0099] The material of the conductive line 155 may be one or more of the following materials: gold, copper, aluminum, silver, or even a tin alloy.

[0100] The advantages of using conductive wires formed by wire bonding are:

[0101] - The connection can be mechanically and electrically stable and withstand CTE differences;

[0102] - Wire bonding is a mature technology, is easily controllable and can provide a variety of wire shapes and lengths;

[0103] -Wire bonding is a clean technology with low risk of glass contamination;

[0104] - Conductive wires formed by wire bonding allow the glass (eg lens or lens pad) to be brought close to the first opening of the module cover.

[0105] Additionally, coupling the conductive line 155 to the conductive lead 134, rather than coupling the conductive line directly to the substrate 102, allows the conductive line to be shorter. An advantage of having a shorter conductive line is that shorts to other components are avoided.

[0106] exist Figure 1 , two conductive leads and two conductive lines have been shown. This is not restrictive, and the optical sensor module may include one conductive lead and one conductive line formed by wire bonding and coupling the conductive trace to the conductive lead. The optical sensor module may also include more than two conductive leads and more than two conductive lines.

[0107] In one variant, each conductive lead can be replaced by a connecting cord. Examples of connecting cords are described in more detail in French patent application No. 2311581 filed on October 25, 2023 in the name of STMICROELECTRONICS INTERNATIONAL NV (law firm case number B22927), which is incorporated herein by reference to the maximum extent permitted by law.

[0108] The conductive leads and connecting cords may be referred to as "conductive strips".

[0109] The conductive traces 152 of the glass 150 , together with the conductive lines 155 , may be used in a protection mechanism to address the above-mentioned safety issues related to the light emitting device 110 .

[0110] Each conductive line 155, and / or a bond of each conductive line 155, may function as a fuse. The bond of a conductive line corresponds to its connection to a conductive trace 152 and / or a conductive lead 134 when formed by wire bonding.

[0111] In fact, the conductive wire 155, and / or the bond of each conductive wire 155, can be arranged to be disconnected in the event that the glass 150 is removed or otherwise becomes detached from the module cover 130. The term "fuse" is used because the conductive wire, and / or the bond of each conductive wire, can be designed to disconnect the electrical connection in order to provide a protection mechanism. In particular, the fuse is configured to be disconnected in the event of a mechanical force caused by the detachment of the glass. For this purpose, the conductive wire can have a diameter or thickness of 25 μm or less, and for example a diameter or thickness of 15 μm or less, thereby making it relatively fragile and likely to be disconnected in the event of glass detachment, and / or the bond of the conductive wire can be formed to be relatively fragile and likely to be disconnected in the event of glass detachment.

[0112] Figure 2A and Figure 2B yes Figure 1 3D view of the module cover 130 of the optical sensor module 100. More specifically, Figure 2A and Figure 2B Conductive leads 134 are shown assembled into channels 135 of module cover 130. Module cover 130 is shown with its bottom side 130B facing upward and its top side 130A facing downward.

[0113] Figure 2A The insertion of the conductive lead 134 into the channel 135 is shown, and Figure 2B The final assembly of the conductive lead 134 into the channel 135 of the module cover 130 is shown. The first end 134A and the second end 134B of the conductive lead 134 protrude out of the module cover 130, for example, to couple to the substrate 102 and the conductive trace 152, respectively.

[0114] The module cover 130 may be plated, for example to provide EMI protection, preferably prior to inserting the conductive leads 134 to avoid contamination of the conductive leads.

[0115] The substrate 102 may include conductive tracks (not shown). Figure 1 ), the conductive track is configured to be at a fixed voltage (such as ground) so that the conductive trace 152 in the glass 150 can be coupled to the fixed voltage through the conductive lead 134 and the substrate 102, and for example through some of the first conductive pads and the second conductive pads.

[0116] By combining the glass 150 with optical surfaces, such as lenses and / or filters, the optical sensor module 100 can additionally provide any optical functionality, such as filtering, beamforming, and / or imaging, while reducing the overall number of components in the module.

[0117] Figure 3A , Figure 3B , Figure 3C and Figure 3D It is a graphic form Figure 1 3-dimensional view and top view of the optical sensor module 100 .

[0118] Figure 3A Shown, in top view, is a starting substrate 102, on which components have been mounted, at least a light emitting device 110, a light receiving sensor 120, interposers 141, 142, a laser driver circuit 144 and SMT components 145. The substrate 102 may be a printed circuit board.

[0119] The top surface 102A of the substrate 102 includes first conductive pads 106 at, or close to, an edge of the substrate.

[0120] An adhesive material 104, for example, an opaque adhesive material such as an opaque glue, is formed on the top surface 102A of the substrate 102. An edge portion 104A of the adhesive material 104 is formed on the edge of the top surface 102A, and a center portion 104B of the adhesive material 104 is formed on the center portion of the top surface 102A between the light receiving sensor 120 and the laser driver 144 / light emitting device 110, thereby defining a future first cavity 136 and a second cavity 137.

[0121] A conductive material 108 , such as a conductive solder or a conductive adhesive, is deposited on the first conductive pad 106 .

[0122] Figure 3B It is shown that, in a 3D view, a first opening 131, a second opening 132 and a partition wall 133 (in Figure 3B The module cover 130 (not shown) is assembled to the substrate 102. The filter 160 may have been attached to the module cover 130. The conductive leads 134 have been assembled to the module cover 130, for example as described with respect to Figure 2A and Figure 2B described. Figure 3B Mainly shown are the second ends 134B of the conductive leads 134 , which protrude out of the module cover 130 .

[0123] During assembly, the bottom surface of the side wall of the module cover 130 is brought into contact with the edge portion 104A of the adhesive 104 so as to be bonded to the substrate 102, and the partition wall 133 of the module cover 130 is brought into contact with the center portion 104B of the adhesive 104, thereby forming a first cavity 136 and a second cavity 137.

[0124] The assembly of the module cover 130 and substrate 102 is then cured, as appropriate, by heat, UV light, or another suitable curing technique, to fully cure the adhesive material and secure the assembly. For example, this assembly may be reflowed.

[0125] Figure 3C It is shown, in a 3-dimensional view, that the glass 150 on the mount 139 is assembled into the first opening 131 of the module cover 130 .

[0126] Figure 3D It is shown that, in the top view, a conductive wire 155 is assembled to the second end 134B of the conductive lead 134 and to the second conductive pad 154 of the glass 150 using wire bonding techniques.

[0127] The optical sensor module 100 may include a detection circuit adapted to detect an open circuit corresponding to detachment of the glass 150 from the module cover 130 .

[0128] The detection circuit may be coupled to the conductive traces 152 and the conductive lines 155 through the conductive leads 134. The detection circuit may be implemented on and / or in the substrate 102. When the glass 150 is in place and the conductive lines 155 and the bonds of the conductive lines 155 are intact, the conductive leads 134, the conductive lines 155, and the conductive traces 152 form a conductive loop, such as a conductive path through the substrate 102. However, if the glass 150 becomes detached, at least one of the conductive lines 155, and / or the bonds of at least one of the conductive lines 155 may be broken, resulting in an open circuit in the conductive loop.

[0129] The detection circuit may be configured to control the light emitting device 110, for example, if an open circuit is detected in the conductive loop, the light emitting device 110 may be disabled. The detection circuit may, for example, periodically or continuously test the conductive loops, for example by passing a current through them, and may disable the light emitting device 110 if an open circuit is detected in the conductive loop.

[0130] In addition to safety issues involving light emitting devices, embodiments may have other applications. For example, embodiments may be used to manage electromagnetic interference (EMI) between an optical sensor module and another electronic device.

[0131] For example, when the optical sensor module is included in an electronic device (host device), electromagnetic interference 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 it may be useful to detect the presence of a nearby object and / or the distance to the nearby object.

[0132] Specifically, the conductive trace may serve as protection against electromagnetic interference (EMI) passing through the first opening of the module cover, for example by providing EMI reflection in the first opening.

[0133] The spacing 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 spacing can be.

[0134] The spacing between the traces is, for example, smaller than the wavelength λ of the signal to be attenuated, and is, for example, a fraction of the wavelength λ, where λ is equal to:

[0135] λ=v / f

[0136] where v is the speed of light, and f is the frequency of the electromagnetic wave chosen to be attenuated.

[0137] Advantageously, the conductive traces may be coupled to a fixed voltage (eg, ground), for example, to provide additional EMI protection.

[0138] Examples of conductive traces are described in more detail in French patent application No. 2311561, filed on October 25, 2023 in the name of STMICROELECTRONICS INTERNATIONAL N.V. (law firm case number B22689), which is incorporated herein by reference to the maximum extent permitted by law.

[0139] 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. For example, instead of being inserted into channels in the module cover, the conductive leads may be a conductive layer formed on the surface of the module cover. The conductive layer may be coated or plated on the module cover, for example, using laser direct structuring (LDS) techniques.

[0140] 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 device; a module cover, the module cover being adapted to at least partially cover the light emitting device, the module cover comprising a first opening located above the light emitting device; at least a conductive strip, said at least a conductive strip being assembled with or included in said module cover; a glass positioned in the first opening or between the first opening and the light emitting device and / or covering the first opening, and adapted to transmit an optical signal emitted by the light emitting device, the glass comprising a conductive trace; as well as At least one conductive line, the at least one conductive line being formed by wire bonding, electrically connects the conductive trace to at least one conductive strip. 2 . The optical sensor module according to claim 1 , wherein a material of each conductive line comprises one or more of the following materials: gold, copper, aluminum, silver or tin alloy. 3 . The optical sensor module according to claim 1 , wherein the at least one conductive line has a thickness less than or equal to 40 μm, such as a thickness less than or equal to 20 μm, and / or a length less than or equal to 2 mm.

4. The optical sensor module of claim 1, further comprising a substrate assembled with the module cover, the at least one conductive strip being coupled to at least a first conductive pad of the substrate, for example using a conductive adhesive material.

5. The optical sensor module of claim 4, wherein the substrate comprises a conductive track configured to be at a fixed voltage, such as ground, the conductive track being coupled to one of the at least one first conductive pads.

6. The optical sensor module according to claim 1, wherein the glass further comprises at least a second conductive pad coupled to the conductive trace, for example at least one second conductive pad is connected to an end of the conductive trace, the at least one conductive strip being coupled to the at least one second conductive pad using the at least one conductive line.

7. The optical sensor module according to claim 1, wherein the at least one conductive line and / or a bond of the at least one conductive line is arranged to be broken in case the glass becomes detached from the module cover.

8. The optical sensor module of claim 7, further comprising a detection circuit adapted to detect when a conductive loop formed by the at least one conductive strip, the at least one conductive line and the conductive trace is broken, the detection circuit being configured to deactivate the light emitting device if the detection circuit detects an open circuit in the conductive loop.

9. The optical sensor module of claim 1, wherein the conductive traces provide electromagnetic interference shielding.

10. The optical sensor module of claim 1, wherein the at least one conductive strip is inserted into at least one channel of the module cover.

11. The optical sensor module according to claim 1, wherein the at least one conductive strip is at least one conductive lead, such as at least one lead frame.

12. The optical sensor module of claim 1, wherein the at least one conductive strip is at least one connecting cord overmolded in the module cover.

13. The optical sensor module according to claim 1, wherein the glass is a lens or a lens pad, the glass for example comprising at least a beam former.

14. The optical sensor module of claim 1, wherein the module cover: is an injection molded cover, the molding material is, for example, a resin; and / or is a plastic module cover; and / or Includes materials suitable for providing electromagnetic interference shielding.

15. The optical sensor module according to claim 1, further comprising: a light receiving sensor at least partially covered by the module cover, the module cover including the second opening located above the light receiving sensor; as well as A filter is provided in or covering the second opening and adapted to transmit the light signal reflected towards the light receiving sensor; the filter for example comprises a second conductive trace providing electromagnetic interference shielding.

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