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 priority to French patent application No. 2311572 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 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] Optical sensors typically include components such as light emitting devices, light receiving sensors (or image 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 bonded 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 generally has 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 or beam 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 the nearby object.

[0007] Light emitting devices used to generate a beam of light are typically covered by glass to protect them from dust; the glass is relatively transparent to light at the wavelength used. The first opening at the top of the light emitting device can also be covered by glass. Glass can also be used as a diffuser to reduce the intensity of the emitted beam to some extent, for example, for safety reasons such as protecting the user. However, if the glass detaches from, breaks, or is otherwise removed from the light emitting device, the intensity of the light emitting device may pose a risk of injury, such as eye damage to the user.

[0008] There is a need to improve optical sensor modules, especially to address the security issues related to light-emitting devices mentioned above.

[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. Utility Model Content

[0010] One embodiment addresses all or some of the drawbacks 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 a light emitting device, the module cover including a first opening located above the light emitting device;

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

[0015] - Glass, positioned in or between the first opening and the light emitting device, and / or glass covering the first opening, and glass adapted to transmit light signals emitted by the light emitting device, the glass including conductive traces; and

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

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

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

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

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

[0021] In one embodiment, the substrate includes a conductive rail (e.g., ground) configured to operate at a fixed voltage, the conductive rail being coupled to one of the at least one first conductive pads.

[0022] In one embodiment, the glass further includes at least a second conductive pad coupled to the conductive trace, for example, the at least one second conductive pad being connected to an end of the conductive trace, and 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 one embodiment, the bonding of at least one conductive line and / or at least one conductive line is arranged to break if the glass becomes detached from the module cover.

[0024] In one embodiment, the module further includes 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 is configured to disable the light emitting device if the detection circuit detects an open circuit in the conductive loop.

[0025] In one embodiment, the conductive trace provides electromagnetic interference shielding.

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

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

[0028] In one embodiment, at least one conductive strip is at least one connecting flex that is molded and wrapped within the module cover.

[0029] In one embodiment, the glass is a lens or lens pad, and the glass includes, for example, at least a beamformer.

[0030] In one embodiment, the module cover:

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

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

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

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

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

[0036] - A filter, in or covering the second opening, and adapted to transmit an optical signal reflected toward the light receiving sensor; the filter, for example, includes a second conductive trace that provides electromagnetic interference shielding. Attached Figure Description

[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 rather than limitation with reference to the accompanying drawings, in which:

[0038] Figure 1 This is a 3D view of an optical sensor module according to one embodiment;

[0039] Figure 2A and Figure 2B yes Figure 1 A 3D view of the module cover of the optical sensor module; and

[0040] Figure 3A , Figure 3B , Figure 3C and Figure 3D It is formed by diagrams Figure 1 3D and top views of the method for the optical sensor module. Detailed Implementation

[0041] The same features have been designated by the same 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.

[0042] 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.

[0043] 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.

[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 relative position qualifiers such as the terms “above,” “below,” “higher,” “lower,” 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.

[0045] Unless otherwise stated, expressions “about,” “approximately,” “basically,” and “on the order of” indicate within 10%, and preferably within 5%.

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

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

[0048] In the following disclosure, unless otherwise indicated, when referring to conductive elements such as conductive traces, pads, strips, or leads, it refers to conductive elements.

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

[0050] The embodiments relate to an optical sensor module. An optical sensor typically includes a light emitting device and a light receiving sensor. The light emitting device includes, 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 includes, for example, a photodiode or multiple photodiodes. The optical sensor also generally includes processing means for processing signals received from the light receiving sensor. The light emitting device and the light receiving sensor can be formed on a 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 generally has a first opening above the light emitting device and a second opening above the light receiving sensor.

[0051] As explained in the background section above, light emitting devices used to generate a light beam are generally covered by glass to protect the device, for example, from dust. The glass is relatively transparent to light at the wavelength used. The glass may cover the first opening. The glass may also be used as a diffuser suitable for reducing the intensity of the emitted light beam to some extent, for example, for safety reasons, such as protecting the user. However, if the glass detaches from, breaks, or is otherwise removed from the light emitting device, the light emitting device will no longer be covered, thus exposing the user to the full intensity of the light beam.

[0052] To address this safety concern involving light-emitting devices, the glass may include conductive traces above the light-emitting device. Generally, the conductive traces are arranged to couple to conductive rails configured at a fixed voltage, which are typically connected to or included in a substrate. This can be accomplished using one or more conductive elements in the cover, for example, via one or more lead frames. In such cases, coupling is provided between the conductive element(s) in the cover and the conductive traces. One solution is to use conductive adhesive between the conductive traces and the conductive element(s). However, coupling using conductive adhesive may be susceptible to dimensional variations between the glass and the cover, potentially due to different coefficients of thermal expansion (CTE), and carries the risk of breakage.

[0053] The inventors have proposed an optical sensor module that makes it possible to overcome all or some of the aforementioned drawbacks, particularly by improving the coupling between conductive traces in the substrate and glass, such as the coupling between conductive elements (one or more) and conductive traces in a cap bonded to the substrate. It is anticipated that this solution will be suitable for addressing security issues related to light-emitting devices.

[0054] Embodiments of the optical sensor module will now be described. These embodiments are non-limiting and various variations will be shown to those skilled in the art in accordance with the indications of this description.

[0055] Figure 1This is a 3D view of an optical sensor module according to one embodiment.

[0056] The optical sensor module 100 includes a light emitting device 110 and a light receiving sensor 120 or an image sensor. For example, the light emitting device 110 includes an LED such as an infrared LED and / or a laser such as a VCSEL, and the light receiving sensor 120 or the image sensor includes a photodiode such as one or more SPADs or multiple 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 reflected back (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 reflected back (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, which are respectively mounted on a first interposer 141 and a second interposer 142. The first interposer 141 and the second interposer 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 may be mounted on the substrate without an interposer.

[0060] In one variant, the light emitting device may consist of only one light source, such as a VCSEL, which may be mounted on an interlayer.

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

[0062] The top surface 102A of the substrate 102 includes first conductive pads 106, which are located, for example, at or near the edge of the substrate (not on the substrate edge). Figure 1 As shown in the text, but Figure 3A (as shown in the image).

[0063] The optical sensor module 100 includes a laser driver 144 configured to control a first light source 111 and a 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 will be conceived by those skilled in the art.

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

[0065] The optical sensor module 100 includes other electronic circuitry or components, such as a surface mount technology (SMT) component 145, which is also mounted on the top surface 102A of the substrate 102. The SMT component 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, or glue.

[0067] 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 components mounted on the substrate 102, including at least the light emitting device 110, the light receiving sensor 120, the interposers 141 and 142, the laser driver 144, and the SMT component 145. At least partially means that all components may be left uncovered; for example, components beneath the openings of the first and second openings may not be covered. The module cover 130 may be substantially opaque to light at the wavelength used.

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

[0069] The first and second openings are located on 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 limiting 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 to substantially prevent 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 on the light emitting device 110, and the second cavity 137 including a second opening 132 on the light receiving sensor 120. A 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 from 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 molding method.

[0072] The optical sensor module 100 also includes:

[0073] - Glass 150, positioned in the first opening 131 or between the first opening 131 and the light emitting device 110, and the glass 150 is adapted to transmit light signals emitted by the light emitting device; and

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

[0075] Glass 150 preferably covers the first opening 131. Glass 150 is preferably attached to the module cover 130. For example, glass 150 is on a mounting member 139 formed within 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, filter 160 preferably covers the second opening 132. Filter 160 is preferably attached to module cover 130. For example, filter 160 is positioned inside module cover 130. In a variant, filter may be mounted outside module cover.

[0077] Glass 150 may include two optical surfaces, which may be two beamformers 151A and 151B, with the first beamformer 151A located above the first light source 111 and the second beamformer 151B located above the second light source 112. Glass 150 may be a lens or a lens pad.

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

[0079] Glass 150 includes a conductive trace 152 that can be embedded in the glass. Glass 150 also includes second conductive pads 154 coupled to the conductive trace 152, such as two second conductive pads, each at an end of the conductive trace.

[0080] In the following disclosure, a conductive trace may be referred to as a "trace". In the following disclosure, a conductive pad may be referred to as a "pad".

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

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

[0083] - An additive process or lift-off, performed in the following order: photolithography, metal deposition, and lift-off; or

[0084] Micro-molding is performed in the following order: metal deposition, photolithography, electrodeposition, stripping, and etching.

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

[0086] In one variant, 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 can be one or more of the following materials: copper (Cu), aluminum (Al), tungsten (W), titanium (Ti), gold (Au), indium tin oxide (ITO), or another metal or metal alloy.

[0088] The conductive traces can be fine and / or thin, for example, having a width of less than 1 micrometer and / or a thickness of less than 100 nanometers, but are not limited to these values. The width and thickness of each conductive trace can be a trade-off between safety features and the optical transmittance of the glass. For example, traces can be wider and / or thicker where they are unlikely to restrict light transmission, and can be finer and / or thinner where they might restrict 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 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 can be a single conductive element, such as a single metal element.

[0091] Each conductive lead 134 can be inserted into the module cover 130 (in the... Figure 2A and Figure 2B (as shown in the diagram) in the recess or channel 135.

[0092] In one variant, the conductive leads may be overmolded during the injection molding operation used to form the module cover. The conductive leads are then overmolded into the module cover.

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

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

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

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

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

[0098] The conductive line 155 may have a length of approximately 2 mm or less than 2 mm.

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

[0100] The advantages of using conduction wires formed by line bonding are:

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

[0102] - Wire bonding is a mature technology that is easy to control and can provide a variety of wire shapes and lengths;

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

[0104] - Conductive lines formed by wire bonding allow glass (e.g., a lens or lens pad) to approach the first opening of the module cover.

[0105] Furthermore, coupling the conductive line 155 to the conductive lead 134, rather than directly to the substrate 102, allows for a shorter conductive line. The advantage of a shorter conductive line is that it avoids short circuits with other components.

[0106] exist Figure 1 The diagram already illustrates two conductive leads and two conductive lines. This is not limiting, and an optical sensor module may include one conductive lead and a conductive line formed by wire bonding and coupling the conductive trace to the conductive lead. An optical sensor module may also include more than two conductive leads and more than two conductive lines.

[0107] In one variant, each conductive lead may be replaced by a connecting wire. An example of a connecting wire is described in more detail in French patent application No. 2311581 filed on October 25, 2023, in the name of STMICROELECTRONICS INTERNATIONAL NV, which is incorporated herein by reference to the fullest extent permitted by law.

[0108] Conductive leads and connecting wires can be referred to as "conductive strips".

[0109] The conductive trace 152 of the glass 150, together with the conductive line 155, can be used in a protection mechanism to address the aforementioned security issues related to the light emitting device 110.

[0110] Each conductive line 155, and / or the bonding of each conductive line 155, can be used as a fuse. The bonding of the conductive line corresponds to its connection with the conductive trace 152 and / or the conductive lead 134 when formed by wire bonding.

[0111] In fact, the conductive wires 155, and / or the bonds of each conductive wire 155, can be arranged to break 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 wires, and / or the bonds of each conductive wire, can be designed to disconnect the electrical connection in order to provide a protective mechanism. Specifically, the fuse is configured to break in the event of mechanical force resulting from the detachment of the glass. For this purpose, the conductive wires 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 them relatively fragile and likely to break in the event of glass detachment, and / or the bonds of the conductive wires can be formed to be relatively fragile and likely to break in the event of glass detachment.

[0112] Figure 2A and Figure 2B yes Figure 1 A 3D view of the module cover 130 of the optical sensor module 100. More precisely, Figure 2A and Figure 2B The conductive lead 134 is shown being assembled into the channel 135 of the module cover 130. The 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 conductive lead 134 into channel 135 is shown, and Figure 2B The conductive lead 134 is shown being finally assembled into a channel 135 of the module cover 130. A first end 134A and a second end 134B of the conductive lead 134 protrude beyond 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 coated, for example, to provide EMI protection, preferably before inserting the conductive lead 134 to avoid contaminating the conductive lead.

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

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

[0117] Figure 3A , Figure 3B , Figure 3C and Figure 3D It is formed by diagrams Figure 1 A 3D view and a top view of the method of the optical sensor module 100.

[0118] Figure 3A As shown in the top view, a starting substrate 102 has components already mounted thereon, including at least a light emitting device 110, a light receiving sensor 120, interposers 141 and 142, a laser driver circuit 144, and an SMT component 145. The substrate 102 may be a printed circuit board.

[0119] The top surface 102A of the substrate 102 includes first conductive pads 106, which are located at or near the edge of the substrate.

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

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

[0122] Figure 3B As shown in the 3D view, it has a first opening 131, a second opening 132, and a partition wall 133 (in Figure 3B Module cover 130 (not shown) is assembled to substrate 102. Filter 160 may have already been attached to module cover 130. Conductive leads 134 have been assembled to module cover 130, for example, as per [reference to...]. Figure 2A and Figure 2B As mentioned above. Figure 3B The second end 134B of the conductive lead 134 is shown, which protrudes beyond the module cover 130.

[0123] During assembly, the bottom surface of the sidewall 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 central portion 104B of the adhesive 104, thereby forming a first cavity 136 and a second cavity 137.

[0124] The components of the module cover 130 and the substrate 102 are then cured as needed using heat, UV light, or another suitable curing technique to fully cure the adhesive material and secure the components. For example, this component can be reflowed.

[0125] Figure 3C As shown in the 3D view, the glass 150 on the mounting piece 139 is assembled into the first opening 131 of the module cover 130.

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

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

[0128] The detection circuit can be coupled to the conductive trace 152 and conductive line 155 via conductive lead 134. The detection circuit can be implemented on and / or in the substrate 102. When the glass 150 is in place and the conductive line 155 and its bonding are intact, the conductive lead 134, conductive line 155, and conductive trace 152 form a conductive loop, for example, through a conductive path in the substrate 102. However, if the glass 150 becomes detached, at least one conductive line in the conductive line 155, and / or the bonding of at least one conductive line in the conductive line 155, can break, resulting in an open circuit in the conductive loop.

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

[0130] Besides addressing safety concerns related to optical emitting devices, the embodiments can also have other applications. For example, the embodiments can be used to manage electromagnetic interference (EMI) between an optical sensor module and another electronic device.

[0131] For example, when an 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 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.

[0132] Specifically, the conductive traces can be used as protection against electromagnetic interference (EMI) through the first opening of the module cover, for example by providing EMI reflection in the first opening.

[0133] The spacing 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 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 can be coupled to a fixed voltage (e.g., ground) to provide additional EMI protection, for example.

[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., which is incorporated herein by reference to the fullest extent permitted by law.

[0139] 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 them. For example, instead of channels inserted into the module cover, conductive leads can be a conductive layer formed on the surface of the module cover. The conductive layer can be coated or plated onto the module cover, for example, formed using laser direct forming (LDS) technology.

[0140] 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, The optical sensor module includes: Light emitting device; A module cover, the module cover being adapted to at least partially cover the light emitting device, the module cover including a first opening located above the light emitting device; At least one conductive strip, said at least one conductive strip being assembled together with or included in the module cover; A glass element positioned within or between the first opening and the light emitting device, and / or the glass covering the first opening, and adapted to transmit an optical signal emitted by the light emitting device, the glass including conductive traces; and At least one conductive line, the at least one conductive line being formed by wire bonding, the at least one conductive line electrically connecting the conductive trace to the at least one conductive strip.

2. The optical sensor module according to claim 1, characterized in that, The materials for each conductor include: gold, copper, aluminum, silver, or tin alloys.

3. The optical sensor module according to claim 1, characterized in that, The at least one conductive line has a thickness of less than or equal to 40 μm and / or a length of less than or equal to 2 mm.

4. The optical sensor module according to claim 1, characterized in that, The at least one conductive line has a thickness of less than or equal to 20 μm and / or a length of less than or equal to 2 mm.

5. The optical sensor module according to claim 1, characterized in that, The optical sensor module also includes a substrate assembled with the module cover, and the at least one conductive strip is coupled to at least one first conductive pad of the substrate using a conductive adhesive material.

6. The optical sensor module according to claim 5, characterized in that, The substrate includes a conductive rail configured at a fixed voltage, and the conductive rail is coupled to one of the at least one first conductive pads.

7. The optical sensor module according to claim 1, characterized in that, The glass also includes at least one second conductive pad coupled to the conductive trace, and the at least one second conductive pad is connected to an end of the conductive trace, wherein the at least one conductive strip is coupled to the at least one second conductive pad using the at least one conductive line.

8. The optical sensor module according to claim 1, characterized in that, The bonding of the at least one conductive line and / or the at least one conductive line is arranged to break if the glass becomes detached from the module cover.

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

10. The optical sensor module according to claim 1, characterized in that, The conductive traces provide electromagnetic interference shielding.

11. The optical sensor module according to claim 1, characterized in that, The at least one conductive strip is inserted into at least one channel of the module cover.

12. The optical sensor module according to claim 1, characterized in that, The at least one conductive strip is at least one conductive lead; or The at least one conductive strip is at least one lead frame.

13. The optical sensor module according to claim 1, characterized in that, The at least one conductive strip is at least one connecting wire molded and covered within the module cover.

14. The optical sensor module according to claim 1, characterized in that, The glass is a lens or lens pad, and the glass includes at least a beamformer.

15. The optical sensor module according to claim 1, characterized in that, The module cover: It is an injection-molded cap, and the molding material is resin; and / or It is a plastic module cover; and / or This includes materials suitable for providing electromagnetic interference shielding.

16. The optical sensor module according to claim 1, characterized in that, The optical sensor module also includes: A light-receiving sensor, at least partially covered by the module cover, the module cover including a second opening above the light-receiving sensor; and A filter is included in or covering the second opening, and the filter is adapted to transmit light signals reflected toward the light receiving sensor; the filter includes a second conductive trace that provides electromagnetic interference shielding.

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