Patent Description:
An example of a known sensing system <NUM> is illustrated in <FIG>. The known sensing system <NUM> comprises an emitter <NUM> configured to emit electromagnetic radiation and a detector <NUM> configured to detect electromagnetic radiation. The emitter <NUM> is located on a first die <NUM> and the detector <NUM> is located on a second die <NUM>. The first and second dies <NUM>, <NUM> are located on a substrate <NUM>. The substrate <NUM> may form part of a printed circuit board (not shown) of an electronic device (not shown). The substrate <NUM> comprises electrical contacts <NUM> for electrically connecting the substrate <NUM> to other circuitry (e.g. one or more processors of the sensing system <NUM> and/or electronic device). The dies <NUM>, <NUM> comprise electrical contacts <NUM> for electrically connecting the dies <NUM>, <NUM> to the substrate <NUM> and other circuitry (e.g. a processor of the electronic device). The known sensing system <NUM> comprises a shield <NUM> located between the emitter <NUM> and the detector <NUM>. The shield <NUM> solely acts to block at least some electromagnetic radiation from propagating directly from the emitter <NUM> to the detector <NUM> to reduce noise in the detector signal. The known sensing system <NUM> further comprises first and second casings <NUM>, <NUM> that are substantially transparent to operating wavelengths of the emitter <NUM> and detector <NUM> (e.g. visible and/or infrared wavelengths of electromagnetic radiation). The first casing <NUM> is configured to protect the detector <NUM> and includes a lens <NUM> for capturing and focusing incident electromagnetic radiation onto the detector <NUM>. The second casing <NUM> is configured to protect the emitter <NUM>. The known sensing system <NUM> further comprises a cap <NUM> comprising a first aperture <NUM> configured to transmit electromagnetic radiation through to the detector <NUM> and a second aperture <NUM> configured to allow electromagnetic radiation emitted by the emitter <NUM> to exit the sensing system <NUM>. The shield <NUM> is typically made from plastic and is glued to the sensing system <NUM> before the first and second casings <NUM>, <NUM> and the cap <NUM> are installed over the shield <NUM>.

<CIT> discloses a wafer level optical proximity sensor including an optical emitter and a photdetector arranged on a substrate and separated by an opaque wall.

<CIT> discloses a printed circuit assembly (PCA) comprising a PCB and a group of components comprising an emitter, a detector and an IC, where multiple PCAs are arranged along each edge of a panel for use in an optical touch sensing system.

It is an aim of the present disclosure to provide a sensing system that addresses one or more problems associated with known sensing systems, or at least provide a useful alternative.

In general, the invention relates to a sensing system comprising an emitter, a detector and an electronic component configured to interact with a circuitry of the sensing system. The electronic component is located at least partially between the emitter and the detector. The electronic component blocks (e.g. absorbs and/or redirects) an amount of electromagnetic radiation that would otherwise propagate directly from the emitter to the detector without leaving the sensing system. The electronic component advantageously not only performs its standard function of interacting with a circuitry of the sensing system, but also blocks at least some electromagnetic radiation from travelling directly from the emitter to the detector. This removes the need for the shield of known sensing systems, which advantageously enables a more compact sensing system. The sensing system according to the invention comprises at least one less component than known sensing systems, thereby simplifying and reducing the cost of manufacture of the sensing system. The electronic component may be sized, shaped and/or positioned to at least partially block a line of sight from the emitter to the detector. The electronic component may comprise a material that is substantially opaque (e.g. blocks about <NUM>% or more of incident radiation) to wavelengths of electromagnetic radiation that are emitted by the emitter and detected by the detector.

According to one aspect of the present disclosure, there is provided a sensing system comprising an emitter configured to emit electromagnetic radiation and a detector configured to detect electromagnetic radiation. The sensing system further comprises an electronic component configured to interact with a circuitry of the sensing system. The electronic component is located at least partially between the emitter and the detector. The electronic component reduces an amount of electromagnetic radiation propagating from the emitter to the detector.

Known sensing systems include a shield located between the emitter and the detector.

The sole purpose of the shield is to reduce the detection of electromagnetic radiation that propagates directly from the emitter to the detector. The shield does this by blocking (e.g. redirecting and/or absorbing) at least some of the radiation that is incident upon the electronic component. Known sensing systems also include electronic components that are solely used for their electronic function. By locating the electronic component at least partially between the emitter and the detector, the electronic component not only performs its standard function of interacting with a circuitry of the sensing system, but also reduces the detection of electromagnetic radiation that propagates from the emitter to the detector without leaving the sensing system. This removes the need for the shield, which advantageously enables a more compact sensing system than known sensing systems. The sensing system comprises at least one less component than known sensing systems, thereby simplifying and reducing the cost of manufacture of the sensing system.

The electronic component may reduce an amount of electromagnetic radiation propagating directly from the emitter to the detector. The electronic component may be configured to at least partially block a line of sight between the emitter and the detector. Reducing the detection of electromagnetic radiation that propagates directly from the emitter to the detector without leaving the sensing system advantageously improves an accuracy of measurements performed using the sensing system. This is because radiation propagating directly from the emitter to the detector (i.e. without leaving the sensing system and interacting with an object that is to be sensed) contributes to measurement noise. The detector is suitable for detecting electromagnetic radiation that leaves the emitter, exits the sensing system via an optical aperture, interacts with (e.g. reflects from) one or more external objects and returns to the detector for detection.

The sensing system may be a time of flight sensing system and/or a proximity sensing system.

The emitter may be any kind of electromagnetic radiation source that is suitable for being incorporated into an electronic device such as, for example, a mobile phone. The emitter may be a diode or a laser such as a vertical cavity surface-emitting laser (VCSEL).

The detector could be any form of photodetector that is suitable for being incorporated into an electronic device such as, for example, a mobile phone. The detector may be a photodiode such as a single photon avalanche diode (SPAD).

The electronic component may be passive (e.g. a capacitor, inductor, resistor, transformer, transducer, etc.), active (e.g. a transistor, diode, a power source, electrostatic discharge device, etc.) and/or electromechanical (e.g. a switch, a piezoelectric device, a fuse, a connector, etc.).

The electronic component may comprise a capacitor configured to at least partially stabilise a voltage of the circuitry and/or reduce an effect of a field acting on the circuitry.

In known sensing systems, an electronic component such as a capacitor is generally not found on the same die or substrate as the circuitry of the sensing system. The capacitor of the sensing system of the present invention advantageously provides at least two functions of reducing the amount of electromagnetic radiation propagating directly from the emitter to the detector, and at least partially stabilising a voltage of the circuitry and/or reducing an effect of a field acting on the circuitry. The field may be an electric field. The field may be a magnetic field. The field may be an electromagnetic field. The field may be an external field, i.e. a field generated outside of the sensing system. The field may be an internal field, e.g. a magnetic field generated by an electrical current passing through the circuitry.

The electronic component may comprise an inductor configured to act as a filter for the circuitry.

The electronic component may comprise a resistor configured to act as a pull-up resistor or a pull-down resistor for the circuitry.

The electronic component may comprise a resistor and a capacitor configured to act as an RC filter for the circuitry.

The electronic component may comprise a diode configured to reduce an effect of a field acting on the circuitry.

The sensing system may comprise a die configured to house the circuitry of the sensing system. The electronic component may be located on the die.

The die may comprise CMOS components for use as an integrated circuit. The die may be located on a substrate of a printed circuit board. The closer the capacitor is located to the circuitry it is configured to interact with, the less the electrical resistance is between the electronic component and the circuitry, and the greater the performance of the electronic component.

The circuitry may comprise an integrated circuit of the sensing system. The die may house the integrated circuit.

The emitter and the detector may be located on the die.

The sensing system may comprise a substrate configured to provide electrical connections between the die and a printed circuit board of the sensing system. The emitter may be located on the substrate. The detector may be located on the die. The emitter may be located on the die. The detector may be located on the substrate.

The closer the electronic component is located to the circuitry (e.g. the die and/or substrate that house the emitter and/or the detector), the less the electrical resistance may be between the electronic component and the circuitry. Reducing the electrical resistance advantageously improves a performance of the electronic component. For example, if the electronic component comprises a capacitor, the ability of the capacitor to stabilise a voltage of the circuitry and/or reduce the effect of a field acting upon the circuitry may be improved by locating the capacitor on the same die and/or substrate as the circuitry.

The sensing system may comprise a filling provided between the electronic component and the sensing system.

The filling may comprise an ink. The filling may comprise a glue configured to secure the electronic component to the sensing system. The filling may be substantially opaque to wavelengths of radiation that are emitted by the emitter and detected by the detector. The filling may advantageously further reduce the amount of electromagnetic radiation propagating directly from the emitter to the detector.

The sensing system may comprise an electrode configured to receive the electronic component. The filling may comprise an electrically conductive adhesive configured to attach the electronic component to the electrode.

The sensing system may comprise two electrodes configured to receive the electronic component. The electronic component may comprise two electrodes configured to connect to the electrodes of the sensing system.

The sensing system may comprise an electrical contact and a conductive connector configured to connect the electronic component to the electrical contact. The filling may comprise a non-conductive adhesive configured to attach the electronic component to the sensing system. This sensing system may advantageously be less expensive to manufacture than other sensing systems.

The sensing system may be a time of flight sensing system. The sensing system may be a proximity sensing system.

An electronic device may comprise the sensing system. The electronic device may be a mobile electronic device such as a mobile phone or a tablet computer. The electronic device may be an industrial electronic device such as an automated manufacturing system or a robotic system such as those used in the automotive manufacturing industry. The electronic device may form part of an automated system for automating a house or a building.

A method of emitting and detecting electromagnetic radiation may comprise using the sensing system.

According to a second aspect of the present disclosure, there is provided a method of manufacturing a sensing system comprising providing an emitter configured to emit electromagnetic radiation, providing a detector configured to detect electromagnetic radiation, providing an electronic component configured to interact with a circuitry of the sensing system, and locating the electronic component at least partially between the emitter and the detector. The electronic component reduces an amount of electromagnetic radiation propagating from the emitter to the detector.

Finally, the present sensing system disclosed here utilises a novel approach at least in that an electronic component configured to interact with a circuitry of the sensing system is located at least partially between the emitter and the detector. The electronic component reduces an amount of electromagnetic radiation propagating from the emitter to the detector.

Some embodiments of the disclosure will now be described by way of example only and with reference to the accompanying drawings, in which:.

Generally speaking, the disclosure provides a sensing system that is suitable for use within an electronic device. The sensing system comprises an emitter configured to emit electromagnetic radiation and a detector configured to detect electromagnetic radiation. The sensing system also comprises an electronic component configured to interact with a circuitry of the sensing system. The electronic component is located at least partially between the emitter and the detector. The electronic component prevents at least some radiation from propagating directly from the emitter to the detector without leaving the sensing system. The electronic component may at least partially block a line of sight between the emitter and the detector. The electronic component may completely block a line of sight between the emitter and the detector.

Some examples of the solution are given in the accompanying figures.

<FIG> schematically depicts a view from above a sensing system <NUM> according to an embodiment of the invention. <FIG> schematically depicts a cross-sectional view from the side of the sensing system <NUM> of <FIG>. The sensing system <NUM> comprises an emitter <NUM> and a detector <NUM>. The emitter <NUM> is configured to emit electromagnetic radiation. The emitter <NUM> may be any kind of electromagnetic radiation source suitable for being incorporated into an electronic device e.g. a diode or a laser such as a vertical cavity surface-emitting laser (VCSEL). The detector <NUM> is configured to detect electromagnetic radiation. The detector <NUM> may be configured to detect the electromagnetic radiation emitted by the emitter <NUM> after the electromagnetic radiation has exited the sensing system <NUM>, interacted with (e.g. reflected from) an external object and propagated back to the detector <NUM>. The detector <NUM> could be any form of photodetector, e.g. a photodiode such as a single photon avalanche diode (SPAD). The sensing system <NUM> may be a time of flight sensing system or a proximity sensing system. The sensing system <NUM> may be suitable for being incorporated into an electronic device such as, for example, a mobile phone or a tablet computer.

The time of flight sensing system may involve the emitter <NUM> emitting electromagnetic radiation, and at least some of that electromagnetic radiation interacting with (e.g. reflecting from) one or more external objects before propagating back to the detector <NUM> for detection. An amount of time between the emitter <NUM> emitting the radiation and the detector <NUM> detecting the radiation may be measured and distance between the electronic device and the one or more external objects may be determined using the known speed of light. The time of flight sensing system may be used for relatively high accuracy measurements. For example, if the time of flight sensing system was incorporated into a mobile phone comprising a camera, the time of flight sensing system may be used to determine a distance between the camera and an external object in order to adjust a focus of the camera to achieve an improved image of the object. Alternative uses of the time of flight sensing system include uses within the automotive industry, robotics, manufacturing, and automated processes. In the case of a time of flight sensing system, the sensing system <NUM> may further comprise a second detector (not shown) located proximate the emitter <NUM>. The second detector may be configured to provide a reference detection value of background electromagnetic radiation for the time of flight sensing system.

The sensing system <NUM> may alternatively be a proximity sensing system in which the emitter <NUM> emits electromagnetic radiation, at least some of which exits the sensing system <NUM> and interacts with (e.g. reflects from) from one or more external objects before being incident on the detector <NUM> for detection. The amount of radiation emitted by the emitter <NUM> may be compared to the amount of radiation detected by the detector <NUM> in order to determine a distance between the electronic device and the one or more external objects. The proximity sensing system may be used for relatively low accuracy measurements. For example, if the proximity sensing system was incorporated into a mobile phone comprising a touch screen, the proximity sensing system may be used to determine whether the phone has been placed proximate a user's ear in order to change an input display on the touch screen to avoid unwanted input commands during a phone call.

The sensing system <NUM> further comprises an electronic component <NUM> configured to interact with a circuitry of the sensing system. The electronic component <NUM> may comprise a passive element (e.g. a capacitor, inductor, resistor, transformer, transducer, etc.), an active element (e.g. a transistor, diode, a power source, electrostatic discharge device, etc.) and/or an electromechanical element (e.g. a switch, a piezoelectric device, a fuse, a connector, etc.). For example, the electronic component <NUM> may comprise a capacitor configured to at least partially stabilize a voltage of the circuitry. During operation of the sensing system, unintended changes in voltage across the circuitry may occur. Example sources of unintended changes in voltage include unwanted power variation from a power supply, ripple voltages within the circuitry, changes in a current draw of the sensing system and/or changes in a current draw of an electronic device that the sensing system forms part of, and/or changes in voltage across the circuitry due to non-zero resistances and/or inductances within the circuitry. The capacitor may generally act as a localized voltage source and/or sink such that changes in current are at least partially counteracted by the capacitor. Alternatively and/or additionally, the capacitor may be configured to reduce an effect of a field (e.g. external and/or internal electromagnetic interference) acting on the circuitry. That is, the capacitor may be configured to improve an electromagnetic compatibility of the sensing system <NUM> with its electromagnetic environment. For example, an external magnetic field may negatively affect an operation of the sensing system <NUM> by generating unwanted currents within the circuitry. Alternatively or additionally, during operation the circuitry of the sensing system <NUM> may generate an internal magnetic field that may produce unwanted currents in the circuitry. The capacitor may act to at least partially counteract the unwanted currents acting on the circuitry.

As another example, the electronic component <NUM> may comprise an inductor. The inductor may, for example, be configured to act as a filter for the circuitry of the sensing system <NUM>. For example, the inductor may be configured to filter out a range of frequencies of alternating current to prevent certain frequencies acting on certain parts of the circuitry.

As a further example, the electronic component <NUM> may comprise a resistor. The resistor may, for example, be configured to act as a pull-up resistor or a pull-down resistor for the circuitry of the sensing system <NUM>. That is, the resistor may be configured to provide a well-defined voltage at an input and/or output of the circuitry.

As another example, the electronic component may comprise a resistor and a capacitor configured to act as a filter network (i.e. an RC filter) for the circuitry of the sensing system <NUM>.

As a further example, the electronic component <NUM> may comprise a diode. The diode may, for example, be configured to reduce an effect of a field (e.g. external and/or internal electromagnetic interference) acting on the circuitry. That is, the diode may be configured to improve an electromagnetic compatibility of the sensing system <NUM> with its electromagnetic environment. The diode may act to at least partially counteract the effects of unwanted currents acting on the circuitry.

Referring again to <FIG>, known sensing systems <NUM> include a shield <NUM> located between the emitter <NUM> and the detector <NUM>. The sole purpose of the shield <NUM> is to at least partially block electromagnetic radiation from propagating directly from the emitter <NUM> to the detector <NUM>.

<FIG> schematically depicts a view from above a portion of a known printed circuit board <NUM> comprising a capacitor <NUM>. The printed circuit board <NUM> may share the same die <NUM> and/or the same substrate (not shown) as the known sensing system shown in <FIG>. The printed circuit board <NUM> comprises an integrated circuit <NUM> having a plurality of signal inputs and outputs <NUM>. First and second voltage source connections <NUM>, <NUM>, ground connection <NUM> and conductive paths <NUM> allow for the provision of electrical energy and signals to the integrated circuit <NUM>. The capacitor <NUM> is provided on the printed circuit board <NUM> outside of and away from the sensing system (not shown in <FIG>). The capacitor <NUM> has the sole function of interacting with the integrated circuit <NUM> (e.g. to stabilise a voltage of the integrated circuit <NUM>). The capacitor <NUM> may be separated from the integrated circuit <NUM> by a distance (e.g. about <NUM>) determined by manufacturing tolerances (e.g. the accuracy of a pick and place tool used to manufacture the printed circuit board <NUM>).

Referring again to <FIG>, by locating the electronic component <NUM> at least partially between the emitter <NUM> and the detector <NUM> the electronic component <NUM> not only performs its standard function of interacting with a circuitry of the sensing system <NUM> but also reduces an amount of electromagnetic radiation propagating directly from the emitter <NUM> to the detector <NUM>. This removes the need for the shield of known sensing systems, which advantageously enables a more compact sensing system <NUM> compared to known sensing systems <NUM>. The sensing system <NUM> according to the invention comprises at least one less component than known sensing systems <NUM>, thereby simplifying and reducing the cost of manufacture of the sensing system <NUM>. The electronic component <NUM> may be configured to at least partially block a line of sight between the emitter <NUM> and the detector <NUM>. Reducing the amount of radiation that propagates directly from the emitter <NUM> to the detector <NUM> advantageously improves an accuracy of the sensing system <NUM> by removing unwanted noise from the detector signal.

The electronic component <NUM> may comprise one or more materials that are substantially opaque to wavelengths of radiation that are emitted by the emitter <NUM> and detected by the detector <NUM>. For example, the emitter <NUM> and the detector <NUM> may be configured to emit and detect visible and/or infrared wavelengths of electromagnetic radiation respectively. For example, the emitter <NUM> and the detector <NUM> may be configured to emit and detect radiation having a wavelength within the range of about <NUM> to about <NUM> respectively. In some embodiments, it may be preferable for the emitter <NUM> and the detector <NUM> to emit and detect non-visible wavelengths of radiation such that the radiation used by the sensing system <NUM> is not detectable to the naked eye.

The electronic component <NUM> is sized, shaped and positioned to at least partially block radiation that would otherwise propagate directly from the emitter <NUM> to the detector <NUM>. The electronic component <NUM> may be sized, shaped and positioned to substantially block an entire line of sight or field of illumination between the emitter <NUM> and the detector <NUM>. A size, shape and position of the electronic component <NUM> may therefore at least partially depend on a geometry of the sensing system <NUM>. For example, the size, shape and position of the electronic component <NUM> may be selected based on a size, shape and position of the emitter <NUM>; a size, shape and position of the detector <NUM>; and/or, a space between the emitter <NUM> and the detector <NUM> across which emitted radiation may propagate. It will be appreciated that the dimensions and geometries of various components of the sensing system <NUM> may vary greatly between different use cases. In general, the electronic component <NUM> is sized, shaped and positioned to at least partially block a path of radiation from the emitter <NUM> to the detector <NUM>. The electronic component <NUM> may be a standard electronic component having a standard size. For example, the electronic component may be a <NUM> imperial capacitor having a length of about <NUM> and a width of about <NUM>, or a <NUM> imperial capacitor having a length of about <NUM> and a width of about <NUM>.

A range of angles across which the radiation leaves the emitter <NUM> and/or a range of angles across which radiation may enter the detector <NUM> may also at least partially determine the size, shape and position of the electronic component <NUM>. In general, a height of the electronic component <NUM> may be greater than a height of the emitter <NUM>.

The size, shape and position of the electronic component <NUM> are preferably selected such that electromagnetic radiation emitted by the emitter <NUM> that does not exit the sensing system <NUM> is prevented from reaching the detector <NUM> by the electronic component <NUM>. The sensing system <NUM> is generally configured such that a measurement portion of radiation emitted by the emitter <NUM> exits the sensing system <NUM>, interacts with the outside environment (e.g. reflect from objects), and returns to the sensing system <NUM> to be detected by the detector <NUM>. The electronic component <NUM> does not prevent the measurement portion of radiation from reaching the detector <NUM>.

The sensing system <NUM> may comprise a cap such as the cap <NUM> shown in <FIG>. A portion of the cap may be shaped to abut an upper surface of the electronic component <NUM> and thereby substantially prevent radiation propagating directly from the emitter <NUM> to the detector <NUM>. The sensing system <NUM> may also comprise first and second casings (not shown), such as the first and second casings <NUM>, <NUM> shown in <FIG>.

In the example of <FIG>, the electronic component <NUM>, the emitter <NUM> and the detector <NUM> are located on a single die <NUM>. The die <NUM> is configured to house a circuitry (e.g. an integrated circuit) of the sensing system <NUM>. The die <NUM> may comprise complementary metal-oxide semiconductor (CMOS) circuitry. The die <NUM> may be located on a substrate (not shown) of a printed circuit board (not shown). The closer the electronic component <NUM> is located to the circuitry of the sensing system <NUM> (e.g. the die <NUM>), the lower the electrical resistance may be between the electronic component <NUM> and the circuitry of the sensing system <NUM>. This may improve a performance of the electronic component <NUM>. By locating the electronic component <NUM> on the same die <NUM> and/or substrate (not shown) as the circuitry of the sensing system <NUM>, the lengths of conductive paths between said components is reduced compared to known sensing systems. This reduces the electrical resistance associated with the conductive paths compared to known sensing systems, which advantageously improves a performance of the electronic component <NUM> compared to known sensing systems.

It may be preferable to maintain a relatively thin (e.g. less than about <NUM>) die <NUM> because the die may be a relatively expensive component of the sensing system <NUM> to manufacture. Locating a larger electronic component <NUM> (e.g. a capacitor) at least partially between the emitter <NUM> and the detector <NUM> may therefore be advantageous because smaller electronic components (e.g. diodes) may be incorporated into the die <NUM> without having to increase a thickness of the die <NUM> to accommodate the smaller components.

The die <NUM> comprises electrical contacts <NUM> for electrically connecting the sensing system <NUM> to other electronics, e.g. a processor of an electronic device (not shown) that incorporates the sensing system <NUM>. The sensing system <NUM> comprises an emitter electrode <NUM> configured to receive the emitter <NUM>. The emitter electrode <NUM> is located on the die <NUM>. The sensing system <NUM> further comprises two electrodes <NUM>, <NUM> configured to receive the electronic component <NUM>. The electrodes <NUM>, <NUM> are located on the die <NUM>. The electrodes <NUM>, <NUM> may increase a surface area of contact between the electronic component <NUM> and the sensing system <NUM> compared to using conductive connectors such as wire bonding. This may advantageously improve an electrical connection between the electronic component <NUM> and the sensing system <NUM> compared to other ways of electrically connecting the electronic component <NUM> to the sensing system <NUM>. The electrodes <NUM>, <NUM> may, for example, comprise gold plates. The electronic component <NUM> may itself comprise two electrodes (not shown) for contacting the electrodes <NUM>, <NUM> of the sensing system <NUM>. The sensing system <NUM> may alternatively comprise two electrical contacts and two conductive connectors (such as the electronic component contacts <NUM>, <NUM> and first and second conductive connectors <NUM>, <NUM> shown in <FIG>) spaced away from the electronic component <NUM> that connect the electronic component <NUM> to the electrical contacts.

A filling <NUM> may be provided between the electronic component <NUM> and the sensing system <NUM>. The filling <NUM> may be configured to further reduce the propagation of electromagnetic radiation directly from the emitter <NUM> to the detector <NUM> without leaving the sensing system <NUM>. The filling <NUM> may comprise an ink and/or a glue configured to secure the electronic component <NUM> to the sensing system <NUM>. In the example of <FIG>, the filling <NUM> comprises an electrically conductive adhesive between the electronic component <NUM> and the electrodes <NUM>, <NUM>. The electrically conductive adhesive advantageously provides multiple functions such as attaching the electronic component <NUM> to the sensing system <NUM>, providing a conductive path between the electronic component <NUM> and the electrodes <NUM>, <NUM>, and further reducing the detection of electromagnetic radiation that would otherwise propagate directly from the emitter <NUM> to the detector <NUM> without leaving the sensing system <NUM>.

<FIG> schematically depict a view from above and a cross-sectional view from the side of an alternative sensing system <NUM> according to an embodiment of the invention. The sensing system <NUM> of <FIG> shares many common features with the sensing system <NUM> of <FIG>. The sensing system <NUM> comprises an emitter <NUM> and a detector <NUM>. The emitter <NUM> is configured to emit electromagnetic radiation. The emitter <NUM> may be any kind of electromagnetic radiation source, e.g. a diode or a laser such as a vertical cavity surface-emitting laser (VCSEL). The detector <NUM> is configured to detect electromagnetic radiation. The detector <NUM> may be configured to detect the electromagnetic radiation emitted by the emitter <NUM> after the electromagnetic radiation has interacted with (e.g. reflected from) an object that is to be sensed by the sensing system <NUM>. The detector <NUM> may be any form of photodetector e.g. a photodiode such as a single photon avalanche diode (SPAD). The sensing system <NUM> is suitable for forming part of an electronic device, such as a mobile phone or tablet computer. The sensing system <NUM> may be a time of flight sensing system or a proximity sensing system as discussed above.

The sensing system <NUM> comprises an electronic component <NUM> configured to interact with a circuitry of the sensing system <NUM>. The electronic component <NUM> may be a passive, active and/or electromechanical element as discussed above. For example, the electronic component <NUM> may comprise a capacitor configured to at least partially stabilize a voltage of the circuitry and/or reduce an effect of a field (e.g. external electromagnetic interference) acting on the circuitry of the sensing system <NUM>.

The electronic component <NUM> is located at least partially between the emitter <NUM> and the detector <NUM>. By locating the electronic component <NUM> at least partially between the emitter <NUM> and the detector <NUM>, the electronic component <NUM> not only performs its standard function of interacting with a circuitry of the sensing system <NUM>, but also reduces the detection of electromagnetic radiation that would otherwise propagate directly from the emitter 410to the detector <NUM>. This advantageously enables a more compact, simplified and relatively inexpensive sensing system <NUM> compared to known sensing systems. The electronic component <NUM> may be configured to at least partially block a line of sight between the emitter <NUM> and the detector <NUM>. The electronic component <NUM> may be configured to completely block a line of sight between the emitter <NUM> and the detector <NUM>.

As discussed above, the electronic component <NUM> of the sensing system <NUM> of <FIG> may be formed of different materials in order to make the electronic component <NUM> substantially opaque to the wavelengths of radiation that are emitted by the emitter <NUM> and detected by the detector <NUM>.

As discussed above, a size, shape and/or a position of the electronic component <NUM> may at least partially depend on a size, shape and position of the emitter <NUM>, a size, shape and position of the detector <NUM>, and a space between the emitter <NUM> and the detector <NUM> across which radiation may propagate. The size, shape and/or position of the electronic component <NUM> is selected such that the amount of electromagnetic radiation propagating directly from the emitter <NUM> to the detector <NUM> is reduced. That is, the electronic component <NUM> acts to absorb and/or redirect electromagnetic radiation that would otherwise propagate directly from the emitter <NUM> to the detector <NUM>.

The sensing system <NUM> may comprise a cap (not shown in <FIG>) such as the cap <NUM> shown in <FIG>. A portion of the cap may be shaped to abut the electronic component <NUM> and substantially prevent radiation propagating directly from the emitter <NUM> to the detector <NUM>. The sensing system <NUM> may also comprise first and second casings (not shown), such as the first and second casings <NUM>, <NUM> shown in <FIG>.

In the example of <FIG>, the electronic component <NUM> and the detector <NUM> are located on a single die <NUM>, and the emitter <NUM> and the die <NUM> are located on a single substrate <NUM>. Having the electronic component <NUM>, the emitter <NUM> and the detector <NUM> on the same substrate keeps the electronic component <NUM> close to the circuitry of the sensing system <NUM>. This advantageously reduces the electrical resistance between the electronic component <NUM> and the circuitry of the sensing system <NUM>, thereby improving the performance of the electronic component <NUM>. For example, if the electronic component <NUM> comprised a capacitor, the performance of the capacitor at stabilising voltage and/or reducing the effect of a field (e.g. external or internal electromagnetic interference) acting upon the circuitry of the sensing system <NUM> may be improved.

In the example of <FIG>, the sensing system <NUM> comprises first and second electronic component contacts <NUM>, <NUM> spaced away from the electronic component <NUM> on the die <NUM> and first and second conductive connectors <NUM>, <NUM> that connect the electronic component <NUM> to the electronic component contacts <NUM>, <NUM>. The sensing system <NUM> may alternatively comprise two electrodes (such as the electrodes <NUM>, <NUM> shown in <FIG>) configured to receive the electronic component <NUM>, thereby removing the need for the first and second conductive connectors <NUM>, <NUM>.

The sensing system <NUM> may comprise a filling (not shown) provided between the electronic component <NUM> and the sensing system <NUM> to further prevent electromagnetic radiation from propagating directly from the emitter <NUM> to the detector <NUM>. In the example of <FIG>, the filling comprises a non-conductive adhesive between the electronic component <NUM> and the sensing system <NUM>.

The die <NUM> comprises electrical contacts <NUM> for electrically connecting the sensing system <NUM> to electrical contacts <NUM> of the substrate <NUM>. The substrate <NUM> may comprise further electrical contacts (not shown), e.g. on the bottom of the substrate <NUM>, to connect the sensing system <NUM> to other electronics such as an integrated circuit, e.g. a processor of an electronic device (not shown). The substrate <NUM> comprises an emitter electrode <NUM> configured to receive the emitter <NUM>.

<FIG> shows a method of manufacturing a sensing system according to an embodiment of the invention. A first step S1 of the method comprises providing an emitter to emit electromagnetic radiation. A second step S2 of the method comprises providing a detector to detect electromagnetic radiation. A third step S3 of the method comprises providing an electronic component to interact with a circuitry of the sensor. A fourth step S4 of the method comprises locating the electronic component at least partially between the emitter and the detector to reduce an amount of electromagnetic radiation emitted by the emitter from being detected by the detector.

The method may also comprise providing a die, providing a substrate and attaching the die to the substrate. The die may comprise the emitter. The substrate may comprise the emitter. Electrical connections between the die and the substrate may be provided, e.g. using wire bonding, and the detector and the electronic component may be provided on the die. First and second casings for the detector and emitter may be provided, and a cap may be positioned to abut the electronic component. The cap may be glued to the sensing system to hold the casings in place.

Embodiments of the present disclosure can be employed in many different applications including time of flight or proximity sensors in electronic devices, for example, in consumer goods (e.g. mobile phones and tablet computers), housing and building automation systems, manufacturing systems and product lines, robotics, automotive, and other industries.

The skilled person will understand that in the preceding description and appended claims, positional terms such as 'above', 'along', 'side', etc. are made with reference to conceptual illustrations, such as those shown in the appended drawings. These terms are used for ease of reference but are not intended to be of limiting nature. These terms are therefore to be understood as referring to an object when in an orientation as shown in the accompanying drawings.

Claim 1:
A sensing system (<NUM>, <NUM>) comprising:
an emitter (<NUM>, <NUM>) configured to emit electromagnetic radiation:
a detector (<NUM>,<NUM>) configured to detect electromagnetic radiation; and
an electronic component (<NUM>, <NUM>) configured to interact with a circuitry of the sensing system, wherein the electronic component (<NUM>, <NUM>) is located at least partially between the emitter (<NUM>,<NUM>) and the detector (<NUM>, <NUM>), and wherein the electronic component (<NUM>, <NUM>) reduces an amount of electromagnetic radiation propagating from the emitter (<NUM>, <NUM>) to the detector (<NUM>, <NUM>); and
wherein the sensing system (<NUM>, <NUM>) is such that a measurement portion of radiation emitted by the emitter (<NUM>, <NUM>) exits the sensing system (<NUM>, <NUM>), interacts with the outside environment, and returns to the sensing system (<NUM>, <NUM>) to be detected by the detector (<NUM>, <NUM>).