Housing cap for optical ranging sensor and electronic system

Abstract

The utility model relates to a housing cap for an optical ranging sensor and an electronic system. A housing cap for an optical ranging sensor and an electronic system for transmitting and receiving optical radiation are provided while minimizing optical noise, such as ambient light, received at a reference sensor of the optical ranging sensor. An example housing cap of an optical ranging sensor may include a barrier wall defining a transmit cavity and a receive cavity. The emission cavity includes an optical radiation source positioned to direct the ranging optical radiation through the emission opening toward the target object, a reference sensor positioned to receive a portion of the ranging optical radiation, and an attenuation wall positioned between the optical radiation source and the reference sensor, an attenuation gap through which the portion of the ranging optical radiation passes is defined. The receiving cavity includes an optical radiation receiver positioned to receive the ranging optical radiation reflected from the target object through the receiver opening.

Description

Technical Field

[0001] Embodiments of this disclosure generally relate to housing caps for optical rangefinders, and more specifically, to housing caps that include attenuation walls to reduce the effect of ambient light on optical rangefinders. Background Technology

[0002] Various example embodiments address technical problems associated with optical noise from undesirable sources in optical sensors, such as optical range sensors, proximity sensors, or image sensors. During operation of an optical range sensor, various ambient light sources may be present in the operating environment. Some ambient light may enter the optical range sensor, for example, through emission openings in a housing cap covering the internal components of the optical range sensor. Increased optical noise from ambient light can lead to inaccurate and / or inconsistent readings from the optical range sensor.

[0003] The applicant has recognized the numerous technical challenges and difficulties associated with reducing optical noise received at the reference sensor of an optical rangefinder. Through exerted efforts, inventiveness, and innovation, the applicant has solved the problems related to the reception of optical noise in optical rangefinders by developing the solutions embodied in this disclosure, which are described in detail below. Utility Model Content

[0004] Various embodiments relate to example housing caps for optical rangefinders and electronic systems for emitting and receiving optical radiation while minimizing optical noise (such as ambient light) received at a reference sensor of the optical rangefinder. An example housing cap for an optical rangefinder may include a barrier wall defining an emitting cavity and a receiving cavity. The emitting cavity includes a light radiation source, a reference sensor, and an attenuation wall. The light radiation source is positioned to direct rangefinder light radiation toward a target object through an emitting opening. The reference sensor is positioned to receive a portion of the rangefinder light radiation. The attenuation wall is positioned between the light radiation source and the reference sensor, defining an attenuation gap through which the portion of the rangefinder light radiation passes. The receiving cavity includes a light radiation receiver positioned to receive rangefinder light radiation reflected from the target object through a receiver opening.

[0005] In some embodiments, the housing cap further includes a top, wherein the transmitter opening and the receiver opening are defined by the top of the housing cap.

[0006] In some embodiments, the attenuation wall further includes an attachment end and a distal end, the attachment end being attached to the top of the housing cap and the distal end extending into the emission cavity.

[0007] In some embodiments, the top and the attenuation wall comprise a single continuous structure.

[0008] In some embodiments, the housing cap is formed by an injection molding process.

[0009] In some embodiments, the light radiation source is attached to the surface of the substrate.

[0010] In some embodiments, the attenuation gap includes a fluid channel between the distal end of the attenuation wall and the surface of the substrate.

[0011] In some embodiments, the housing cap further includes an electromagnetic interference shield that is attached to the surface of the substrate and covers at least a portion of the light radiation source.

[0012] In some embodiments, the attenuation gap includes a fluid channel between the distal end of the attenuation wall and the electromagnetic interference shield.

[0013] In some embodiments, the barrier wall creates an optically impermeable barrier between the transmitting cavity and the receiving cavity.

[0014] In some embodiments, the attenuation wall blocks the reference sensor from receiving ambient light entering the emission opening.

[0015] In some embodiments, the attenuation gap is between 80 micrometers and 160 micrometers.

[0016] In some embodiments, the distance from the light radiation source to the attenuation wall is between 2.75 mm and 3.25 mm.

[0017] In some embodiments, the firing opening includes a diameter between 1.75 mm and 2.25 mm.

[0018] In some embodiments, the housing cap further includes a emitting lens positioned in the emitting opening.

[0019] In some embodiments, the distance from the light radiation source to the emitting lens is between 2.25 mm and 2.75 mm.

[0020] In some embodiments, the reference sensor distance, which defines the distance between the reference sensor and the light radiation source, is between 4.25 mm and 4.5 mm.

[0021] An electronic system configured to determine the proximity of a target object is also provided. The electronic system includes an outer cover and an optical ranging sensor disposed on the inner side of the outer cover opposite the target object. The optical ranging sensor includes a housing cap with a barrier wall defining a transmitting cavity and a receiving cavity. The transmitting cavity includes a light source, a reference sensor, and an attenuation wall. The light source is positioned to direct ranging light radiation toward the target object through a transmitting opening. The reference sensor is positioned to receive a portion of the ranging light radiation. The attenuation wall is positioned between the light source and the reference sensor, defining an attenuation gap through which the portion of the ranging light radiation passes. The receiving cavity includes a light radiation receiver positioned to receive ranging light radiation reflected from the target object through a receiving opening.

[0022] In some embodiments, the housing cap further includes a top defining a transmit opening and a receive opening, wherein the attenuation wall further includes an attachment end and a distal end, the attachment end being attached to the top of the housing cap and the distal end extending into the transmit cavity.

[0023] In some embodiments, the attenuation gap is between 80 micrometers and 160 micrometers. Attached Figure Description

[0024] Referring now to the accompanying drawings. The components shown in the drawings may or may not be present in some embodiments described herein. According to exemplary embodiments of this disclosure, some embodiments may include fewer (or more) components than those shown in the drawings.

[0025] Figure 1 A cross-sectional view of an example optical ranging sensor, according to an exemplary embodiment of the present disclosure, is depicted, which emits ranging light radiation at a target object and receives reflected ranging light radiation.

[0026] Figure 2 A cross-sectional view of an example optical ranging sensor including a housing cap with attenuation walls, according to an example embodiment of the present disclosure, is depicted.

[0027] Figure 3 A cross-sectional perspective view of an example optical ranging sensor including an electromagnetic interference shield, according to an example embodiment of the present disclosure, is depicted.

[0028] Figure 4 A cross-sectional view of an example attenuation wall, including example measurements, is depicted according to an example embodiment of the present disclosure.

[0029] Figure 5 Several example electronic systems including an optical ranging sensor are shown according to exemplary embodiments of the present disclosure. Detailed Implementation

[0030] Example embodiments will be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, embodiments of the utility model of this disclosure. In fact, embodiments of this disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to enable this disclosure to meet applicable legal requirements. The same numerals always denote the same elements.

[0031] Overview

[0032] Various example embodiments address technical problems associated with receiving optical noise at a reference sensor (e.g., an optical range sensor, optical proximity sensor, optical image sensor, etc.) of an optical range sensor. As those skilled in the art to which this disclosure pertains will understand, there are numerous example scenarios in which the accuracy and consistency of an optical sensor can be improved by reducing the amount of optical noise received at the reference sensor.

[0033] During operation of an optical rangefinder, light radiation is emitted from a light radiation source. This light radiation can be guided toward a target object through one or more optical structures, a display screen, a cover glass, and / or lenses. The emitted light radiation can interact with the target object, causing a reflected portion of the emitted light radiation to be reflected toward a light radiation receiver on the optical rangefinder. Furthermore, a portion of the emitted light radiation can be internally guided toward a reference sensor. The reference sensor can be configured to generate a reference signal for comparison with the reflected portion of the emitted light radiation. Based on the comparison between the reflected portion of the emitted light radiation returning from the target object and the reference signal from the reference sensor, the optical rangefinder can determine certain characteristics related to the proximity of the target object, such as the distance to the target object, the position of the target object, the motion of the target object, and / or the velocity of the target object.

[0034] In addition to the portion of emitted light radiation internally guided toward the reference sensor, optical noise from undesirable sources such as ambient light in the operating environment can be received by the reference sensor. Optical noise received from undesirable sources can weaken the reference signal generated by the reference sensor. For example, optical noise from ambient light can enter through the transmission opening of the optical rangefinder and interact with the reference sensor. An increase in optical noise at the reference sensor is equivalent to a decrease in the signal-to-noise ratio (SNR) of the reference portion of the emitted light radiation. As the SNR of the reference signal decreases due to optical noise, the output from the optical rangefinder becomes increasingly inaccurate and inconsistent. Optical noise from the operating environment becomes even more problematic in optical rangefinders with wide-angle transmission apertures designed to emit light radiation over an increased emission field.

[0035] Previous attempts to mitigate the reception of optical noise at the reference sensor have included placing an optical filter on the emission aperture. The optical filter allows emitted light to escape but prevents optical noise from entering the optical rangefinder. However, an optical filter on the emission aperture increases the overall cost of the optical rangefinder. Furthermore, positioning the sensor on the emission aperture can increase the complexity of manufacturing the optical rangefinder. Additionally, the adhesive used to attach the filter can crack and collapse over time, causing the filter to move or shift during operation. With the increasing demand for high-accuracy optical rangefinders, there is a need to reduce the amount of optical noise received at the reference sensor of the optical rangefinder, while subsequently reducing cost, simplifying manufacturing complexity, and increasing reliability.

[0036] The various example embodiments described herein utilize various techniques to reduce or eliminate the reception of optical noise at the reference sensor of an optical rangefinder. For example, in some embodiments, an attenuation wall is placed in the emission cavity between the light source and the reference sensor in the optical rangefinder. The attenuation wall prevents optical noise (e.g., ambient light from the operating environment) entering the emission cavity of the optical rangefinder from interacting with the reference sensor. Additionally, the attenuation wall defines an attenuation gap between its distal end and the substrate surface or internal structure of the optical rangefinder. The attenuation gap allows a portion of the emitted light radiation to be emitted to the reference sensor while blocking optical noise from reaching it.

[0037] As a result of the exemplary embodiments described herein, and in some examples, the accuracy and reliability of optical ranging sensors can be significantly improved. Furthermore, the cost and complexity required to manufacture optical ranging sensors can be greatly reduced.

[0038] For example, attenuation walls reduce the amount of optical noise received at the reference sensor of an optical rangefinder. This reduction in optical noise at the reference sensor allows for the generation of an accurate reference signal based on the emitted light radiation. When compared to the rangefinder light radiation reflected from the target object, the accurate reference signal produces more accurate distance and motion data.

[0039] Furthermore, the attenuation wall eliminates the need for an optical filter placed on the emission aperture of the optical rangefinder. Optical filters increase the overall cost of the optical rangefinder due to their cost and the additional manufacturing complexity of mounting them. Moreover, the methods used to attach the optical filter can fail. For example, the adhesive used to attach some optical filters may crack, causing the filters to separate. Once the optical filters have separated, the accuracy of the optical rangefinder may be compromised.

[0040] Example optical ranging sensor

[0041] Now for reference Figure 1 An example optical ranging sensor 100 is provided. For example... Figure 1 As shown, the example optical rangefinder 100 includes a housing cap 110, which includes a barrier wall 111 dividing the optical rangefinder 100 into two cavities (emitting cavity 103 and receiving cavity 105). The emitting cavity 103 includes a light radiation source 102 and a reference sensor 106 attached to a substrate 108. The light radiation source 102 is configured to output range-finding light radiation 115a and is aligned with an emission opening 120 in the housing cap 110, such that the range-finding light radiation 115a is guided toward a target object 117 through an emission lens 112a and an emission filter 113a. The target object 117 reflects at least a portion of the range-finding light radiation 115a back to the optical rangefinder 100 as reflected range-finding light radiation 115b. The reflected range-finding light radiation 115b is received through a receiving opening 121 in the housing cap 110 and collected by a light radiation receiver 104 attached to the substrate 108. The receiving opening 121 includes a receiver filter 113b and a receiver lens 112b, used to guide the reflected ranging light radiation 115b into the receiving cavity 105 and toward the light radiation receiver 104. Figure 1 As shown, the operating environment 118 of the optical rangefinder 100 may include optical noise 119, such as ambient light. A portion of the optical noise 119a can enter through the emission opening 120 and interact with the reference sensor 106. The optical noise 119 received at the reference sensor 106 affects the performance of the optical rangefinder 100. Figure 1 As further depicted, the outer cover 114 is located between the optical range sensor and the target object 117.

[0042] like Figure 1 As depicted, the example optical rangefinder 100 includes a housing cap 110. The housing cap 110 is any encapsulation, cover, container, or other covering configured to protect the internal electrical components and circuitry of the optical rangefinder 100. The housing cap 110 may include plastic, ceramic, or other protective materials. The housing cap 110 is attached to a substrate 108 to provide stability and further protect the internal electrical components of the optical rangefinder 100. Although in Figure 1 While depicted as being attached to substrate 108, in some embodiments, housing cap 110 may be attached to a receiving element configured to receive and attach housing cap 110. In some embodiments, housing cap 110 may also include conductive pins and / or conductive pads to provide electrical connections to internal electrical components of optical range sensor 100.

[0043] like Figure 1As further depicted, the housing cap 110 includes a barrier wall 111. The barrier wall 111 is any protrusion, attachment, or other structure that is part of or attached to the housing cap 110, and is designed to be close to the substrate 108 or other surface to divide the interior of the optical rangefinder sensor 100 into a transmitting cavity 103 and a receiving cavity 105. In some embodiments, the housing cap 110 may be attached to the substrate or other surface at the barrier wall 111. The barrier wall 111 may comprise plastic, ceramic, or other protective materials. In some embodiments, the barrier wall 111 and the housing cap 110 may form a single, continuous structure. For example, the barrier wall 111 may be formed together with the housing cap 110 as part of an injection molding process. The barrier wall 111 forms an optically impermeable barrier between the transmitting cavity 103 and the receiving cavity 105. The optically impermeable barrier prevents light or other light radiation from passing from one side of the barrier wall 111 to the other. For example, the ranging light radiation 115a emitted from the light radiation source 102 cannot pass through the barrier wall 111 and enter the receiving cavity 105.

[0044] like Figure 1 As further described, the optical ranging sensor 100 includes a light source 102. The light source 102 can be any light source, such as a laser diode, a light-emitting diode, a light bulb, a semiconductor device, or other photon-emitting structure configured to generate ranging light radiation 115a. In some embodiments, the light source 102 may include a semiconductor laser diode, such as a vertical-cavity surface-emitting laser (VCSEL) and / or an edge-emitting laser diode. Typically, the light source 102 can output a coherent beam when a current is received.

[0045] like Figure 1Further described, the light source 102 is configured to output ranging light radiation 115a. Ranging light radiation 115a is any optical signal emitted by the light source 102 toward the target object 117 to determine characteristics related to the position and / or motion of the target object 117. In some embodiments, ranging light radiation 115a may be a pulsed laser signal. For example, the light source 102 may be configured to generate uniform laser pulses. Once the reflected ranging light radiation 115b is received at the light radiation receiver 104, the pulsed laser signal enables the controller to determine the time of flight of the ranging light radiation 115a. In some embodiments, ranging light radiation 115a may be a continuous-wave laser signal. In such embodiments, a continuous-wave laser signal enables the controller to determine the proximity of the target object 117 by correlating the phase change of the ranging optical radiation 115a as it is emitted by the optical source 102, reflected from the target object 117, and subsequently received by the optical radiation receiver 104. Characteristics related to the position and / or motion of the target object 117 may include the distance of the target object 117 from the optical sensor, the position of the target object 117, the velocity of the target object 117, the direction of motion of the target object 117, and other similar characteristics related to the position of the target object 117 in the operating environment 118.

[0046] like Figure 1 As further depicted, the ranging light radiation 115a is emitted through an emission opening 120 defined by the housing cap 110. The emission opening 120 is any hole, slit, aperture, or other opening aligned with the light radiation source 102 to allow the ranging light radiation 115a to be emitted toward the target object 117. The emission opening 120 may include optical features such as lenses (e.g., emission lens 112a), structures, beamforming elements or light diffusers, or other features that guide the ranging light radiation 115a toward the target object 117 and / or various portions of the target object 117.

[0047] like Figure 1 As depicted, one technique for preventing optical noise 119 from entering the emission cavity 103 is to place an emission filter 113a on at least a portion of the emission opening 120. The emission filter 113a can be designed to block at least a portion of the spectrum from entering the emission cavity 103. However, the emission filter 113a may allow optical noise 119 of certain wavelengths to enter the emission cavity 103. Additionally, the emission filter 113a increases the overall cost of the optical rangefinder 100. Furthermore, the emission filter 113a may be difficult to align and attach to the emission opening 120. The emission filter 113a may also fail; for example, the emission filter 113a may separate, thus allowing all optical noise 119 to enter the emission cavity 103.

[0048] like Figure 1 As further depicted, the example optical rangefinder 100 includes a substrate 108. The substrate 108 is any structure configured to support the attachment of components of the optical rangefinder 100, including a housing cap 110. In some embodiments, the substrate 108 may include a printed circuit board (PCB) or alumina ceramic, including electrical connections for connecting components of the optical rangefinder 100 to a processor, controller, analog-to-digital converter, or other electrical components. In some embodiments, the light source 102, the reference sensor 106, and the light receiver 104 may all be electrically coupled through the substrate 108.

[0049] like Figure 1 As further described, the optical rangefinder 100 includes a reference sensor 106. The reference sensor 106 is any photosensitive sensor configured to generate a reference signal based on a portion of the rangefinder light radiation 116 received from the light radiation source 102. During operation of the optical rangefinder 100, the light radiation source 102 emits rangefinder light radiation 115a toward the target object 117. A portion of the rangefinder light radiation 116 is directed toward the reference sensor. Therefore, the received portion of the rangefinder light radiation 116 can be compared with the reflected rangefinder light radiation 115b reflected from the target object 117. By comparing the reference signal generated by the reference sensor 106 with the electrical signal generated by the light radiation receiver 104, the physical characteristics of the target object 117, including physical characteristics related to the position and motion of the target object 117, can be determined.

[0050] However, as Figure 1 As further described, the operating environment 118 of the optical rangefinder 100 may include optical noise 119. Optical noise is any light or other light radiation in the operating environment 118 of the optical rangefinder 100 that can enter the emission cavity 103 through the emission opening 120 or another opening in the housing cap 110. Optical noise may include ambient light and / or light from other light radiation sources. Figure 1 As depicted, a portion of the optical noise 119a can enter the emission cavity 103 and be captured by the reference sensor 106. This portion of the optical noise 119a in the emission cavity 103 may be particularly prevalent if the emission filter 113a is separated or removed. The portion of the optical noise 119a captured by the reference sensor 106 may adversely affect the performance and accuracy of the optical ranging sensor 100, because the reference signal generated by the reference sensor 106 may be altered due to the presence of the optical noise 119a captured by the reference sensor 106.

[0051] like Figure 1As further depicted, ranging light radiation 115a emitted by light radiation source 102 is directed toward target object 117. Target object 117 is any object, structure, person, entity, or other item located within the line of sight of ranging light radiation 115a emitted by optical ranging sensor 100. In some embodiments, optical ranging sensor 100 may be configured to determine one or more proximity characteristics of target object 117, such as spatial location, composition, proximity, movement, and / or speed of target object 117. For example, in some embodiments, optical ranging sensor 100 may be located below the electronic display screen of a mobile device (e.g., cover 114) and may be configured to detect target object 117 within a predetermined threshold distance of optical ranging sensor 100. When target object 117 is within the predetermined threshold distance of optical ranging sensor 100, mobile device may deactivate touchscreen, turn off display, or take any other related action.

[0052] like Figure 1 As further described, a portion of the ranging optical radiation 115a can be reflected from the target object 117 as reflected light radiation 115b. The reflected light radiation 115b is any portion of the ranging light radiation 115a emitted by the light radiation source 102 of the optical ranging sensor 100 that is reflected by the target object 117 and received by the light radiation receiver 104 of the optical ranging sensor 100. The reflected ranging light radiation 115b is used to determine the proximity characteristics of the target object 117.

[0053] like Figure 1 As further described, the optical ranging sensor 100 includes a light radiation receiver 104. The light radiation receiver 104 is any of the following: one or more photodiodes, integrated circuits, sensors, photodiodes, or other structures that generate an electrical signal due to light received at the light radiation receiver 104. The current output from the light radiation receiver 104 can be used to determine the intensity or amplitude of the light radiation striking the light radiation receiver 104. In some embodiments, the light radiation receiver 104 may be a photosensitive semiconductor diode that generates electron-hole pairs at a pn junction when a photon of sufficient energy strikes the light radiation receiver 104.

[0054] like Figure 1As depicted, a light radiation receiver 104 is electrically connected to a substrate 108. In some embodiments, the light radiation receiver 104 may be further electrically connected to a processing device. The processing device may be configured to receive an electrical signal generated by the light radiation receiver 104 representing the intensity of the reflected ranging light radiation 115b received at the light radiation receiver 104, and an electrical signal generated by a reference sensor 106. In some embodiments, the processing device may determine the time of flight and / or the phase variation of the light radiation, and determine one or more characteristics related to the physical location of the target object 117.

[0055] like Figure 1 As further depicted, the reflected ranging light radiation 115b is received by the light radiation receiver 104 through a receiving opening 121 defined by the housing cap 110. The receiving opening 121 is any hole, slit, aperture, or other opening aligned with the light radiation receiver 104 to allow the reflected ranging light radiation 115b to be emitted toward the light radiation receiver 104. The receiving opening 121 may include optical features such as lenses (e.g., receiver lens 112b), structures, beamforming elements, or light diffusers, or other features that guide and / or filter the reflected ranging light radiation 115b. Furthermore, a receiver filter 113b may be located on the receiving opening 121 to block optical noise 119 and other unwanted light radiation from entering the receiving cavity 105.

[0056] like Figure 1 As further depicted, the outer cover 114 is located between the optical range sensor 100 and the target object 117. The outer cover 114 is any transparent and / or translucent device located outside the housing cap 110, through which the ranging light radiation 115a and reflected ranging light radiation 115b pass before and after encountering the target object 117. In some embodiments, the outer cover 114 may be an electronic display screen of an electronic device such as a mobile phone. In such embodiments, the optical range sensor 100 emits and receives light radiation through the electronic display screen to determine the proximity characteristics of the target object 117 outside the mobile device. The electronic display screen may be transparent or translucent for certain wavelengths of light, such that the reflected ranging light radiation 115b can be received by a light radiation receiver 104 behind or below the electronic display screen.

[0057] Example shell cap

[0058] Now for reference Figure 2 An example optical ranging sensor 200 is provided, including an attenuation wall 222 positioned to block optical noise 219 received at a reference sensor 206. For example... Figure 2As shown, the optical rangefinder 200 includes a housing cap 210 having a top 226 and a barrier wall 211 dividing the optical rangefinder 200 into two cavities (emitting cavity 203 and receiving cavity 205). The emitting cavity 203 includes a light radiation source 202 and a reference sensor 206 attached to a substrate 208 (which has a top surface 208a). The light radiation source 202 is aligned with an emission opening 220 in the top 226 of the housing cap 210 and is configured to output rangefinder light radiation 215a toward a target object through an emission lens 212a. The target object reflects at least a portion of the rangefinder light radiation 215a back to the optical rangefinder 200 as reflected rangefinder light radiation 215b. The reflected rangefinder light radiation 215b is received through a receiver opening 221 in the top 226 of the housing cap 210 and collected by a light radiation receiver 204 attached to the substrate 208. The receiver opening 221 includes a receiver filter 213b and a receiver lens 212b, which are configured to guide the reflected ranging light radiation 215b into the receiver cavity 205 and toward the light radiation receiver 204.

[0059] like Figure 2 As depicted, the emitting lens (e.g., emitting lens 112a) has been removed. Optical noise 219 from the operating environment can enter the emitting cavity 203 through the emitting opening 220. However, the housing cap 210 includes an attenuation wall 222 having an attachment end 222a and a distal end 222b, extending from the top 226 of the housing cap 210 toward the substrate 208. The attenuation wall 222 forms an attenuation gap 224 between the distal end 222b of the attenuation wall 222 and the top surface 208a of the substrate 208, allowing a portion of the ranging light radiation 216 to be transmitted to the reference sensor 206 while blocking the optical noise 219.

[0060] like Figure 2 As depicted, the housing cap 210 of the example optical rangefinder 200 includes a top 226. The top 226 of the housing cap 210 defines the emission opening 220 and the receiving opening 221 of the optical rangefinder 200. Thus, the top 226 of the housing cap 210 includes the portion where ranging light radiation 215a is guided and reflected ranging light radiation 215b returns within the housing cap 210. The top 226 allows the ranging light radiation 215a, 215b to flow into and out of the optical rangefinder 200, while substantially blocking optical noise 219 from the operating environment from entering the emission cavity 203 and the receiving cavity 205. Furthermore, the top 226 of the housing cap 210, together with the outer wall of the housing cap 210, provides protection for the internal electrical components of the optical rangefinder.

[0061] like Figure 2As further depicted, the housing cap 210 includes an attenuation wall 222 extending from the top 226 of the housing cap 210 toward the top surface 208a of the substrate 208 into the emission cavity 203. The attenuation wall 222 is any barrier, wall, or obstruction defined by the housing cap 210 and is located within the emission cavity 203 between the emission opening 220 aligned with the light radiation source 202 and the reference sensor 206. The attenuation wall 222 comprises any optically impermeable material. In some embodiments, the attenuation wall 222 comprises plastic, ceramic, or other materials constituting the housing cap 210. In some embodiments, the attenuation wall 222, barrier wall 211, top 226, and housing cap 210 may form a single continuous structure. For example, the attenuation wall 222 may be formed together with the housing cap 210 as part of an injection molding process. Alternatively, in some embodiments, the attenuation wall 222 may include a material separate from the housing cap 210 and / or be attached separately to the top 226 of the housing cap 210.

[0062] like Figure 2 As depicted, attenuation wall 222 further defines attenuation gap 224. Attenuation gap 224 is any opening, aperture, slit, hole, or other gap in attenuation wall 222 that allows light radiation to pass from one side of attenuation wall 222 to the other. In some embodiments, attenuation gap 224 may allow fluid to pass from one side of attenuation wall 222 to the other. The fluid passage allows fluids such as liquids or gases, other than light radiation, to pass through attenuation gap 224.

[0063] like Figure 2 As depicted, the attenuation wall 222 includes an attachment end 222a and a distal end 222b. The attachment end 222a connects the attenuation wall 222 to the top 226 of the housing cap 210. The distal end 222b extends into the emission cavity 203 to form an attenuation gap 224. Figure 2 As depicted, an attenuation gap 224 is formed between the distal end 222b of the attenuation wall 222 and the top surface 208a of the substrate 208. In some embodiments, the attenuation gap 224 may be formed by a gap or hole in the attenuation wall 222. For example, the attenuation wall 222 may be divided into two parts, one extending from the top 226 of the housing cap 210 into the emission cavity 203, and the other extending from the top surface 208a of the substrate 208 into the emission cavity 203. The attenuation gap 224 may be formed at the point where the two parts of the attenuation wall intersect. In some embodiments, the attenuation gap 224 may be formed between the distal end 222b of the attenuation wall 222 and another structure of the optical ranging sensor 200. For example, the attenuation gap 224 may be formed between the distal end 222b of the attenuation wall 222 and electrical components, protective encapsulation of electrical components, support structures, or any other structures in the emission cavity 203 of the optical ranging sensor 200. Figure 3In one specific embodiment depicted, an attenuation gap is formed between the far end of the electromagnetic interference (EMI) shield and the attenuation wall.

[0064] Now for reference Figure 3 An example optical ranging sensor 300, which also includes an EMI shielding element 330, is provided. Figure 3 The example optical rangefinder 300 depicted includes a housing cap 310 having a top 326 and including a barrier wall 311 dividing the optical rangefinder 300 into two cavities (emitting cavity 303 and receiving cavity 305). The emitting cavity 303 includes a light source 302 and a reference sensor 306 attached to a substrate 308. The light source 302 is aligned with an emitting opening 320 in the top 326 of the housing cap 310 and is configured to output rangefinder light radiation toward a target object through an emitting lens 312a. The top 326 of the housing cap 310 also defines a receiver opening 321 configured to receive reflected rangefinder light radiation and guide the reflected rangefinder light radiation toward a light radiation receiver 304 attached to the substrate 308. The receiver opening 321 includes a receiver filter 313b and a receiver lens 312b configured to guide reflected rangefinder light radiation 215b into the receiving cavity 305 and toward the light radiation receiver 304.

[0065] like Figure 3 As further depicted, the housing cap 310 includes an attenuation wall 322 having an attachment end 322a and a distal end 322b, extending from the top 326 of the housing cap 310 into the emission cavity 303. The emission cavity 303 also includes an EMI shield 330, which surrounds multiple electrical components inside the optical ranging sensor 300. The attenuation wall 322 forms an attenuation gap 324 between the distal end 322b of the attenuation wall 322 and the surface of the EMI shield 330, thereby allowing a portion of the ranging optical radiation to be transmitted to the reference sensor 306 while blocking optical noise.

[0066] like Figure 3 As depicted, attenuation gap 324 is formed between the distal end 322b of attenuation wall 322 and the internal structure of optical ranging sensor 300 (e.g., EMI shield 330). Although depicted as EMI shield 330 forming attenuation gap 324, attenuation gap 324 can be formed between attenuation wall 322 and any structure within emission cavity 303 configured to block light radiation. For example, the internal structure can be any combination of protective covering, surface of one or more electrical components, insulating material, encapsulation of electrical components, EMI shield 330, or other elements.

[0067] EMI shielding 330 is typically attached to substrate 308 or other attachment surfaces within optical range sensor 300 and is positioned to enclose one or more electrical components. In some embodiments, the electrical components may be susceptible to interference from external electromagnetic emissions. For example, the electrical components may be configured to transmit and receive data. External electromagnetic emissions may corrupt data during processing or transmission, or may even cause the electrical components to malfunction. EMI shielding 330 may be positioned to envelop one or more electrical components susceptible to external electromagnetic radiation. In some embodiments, the electrical components may be identified as source emitters of electromagnetic radiation. EMI shielding 330 may be positioned to enclose such electrical components to prevent internal electromagnetic radiation from escaping EMI shielding 330. EMI shielding 330 may also include one or more openings to allow the emission of optical and / or electrical signals, such as range-finding light radiation.

[0068] The EMI shield 330 may be opaque to light radiation, preventing light radiation from penetrating or passing through it. Therefore, in some embodiments, the EMI shield 330 positioned near the distal end 322b of the attenuation wall 322 may form an attenuation gap 324 through which a portion of the light radiation from the light radiation source 302 can pass, while blocking at least a portion of the optical noise from entering the emission cavity 303 through the emission opening 320.

[0069] Now for reference Figure 4 An example optical rangefinder sensor 400 is provided. As depicted, the example optical rangefinder sensor 400 includes a housing cap 410 that includes a barrier wall 411 dividing the optical rangefinder sensor 400 into two cavities (emitting cavity 403 and receiving cavity 405). The emitting cavity 403 includes a light radiation source 402 and a reference sensor 406 attached to a substrate 408. The light radiation source 402 is aligned with an emission opening 420 in the housing cap 410 and is configured to output range-measuring light radiation through an emission lens 412a. The housing cap 410 also defines a receiver opening 421, which is configured to receive reflected range-measuring light radiation and direct the reflected range-measuring light radiation toward a light radiation receiver 404 attached to the substrate 408.

[0070] like Figure 4 As further depicted, the housing cap 410 includes an attenuation wall 422 having an attachment end 422a and a distal end 422b, extending from the top of the housing cap 410 to the emission cavity 403. The emission cavity 403 also includes an EMI shield 430, which surrounds multiple electrical components inside the optical ranging sensor 400. The attenuation wall 422 forms an attenuation gap 424 between the distal end 422b of the attenuation wall 422 and the surface of the EMI shield 430, thereby allowing a portion of the ranging light radiation to be transmitted to the reference sensor 406 while blocking optical noise.

[0071] like Figure 4 As depicted, the attenuation wall 422 and the EMI shield 430 form an attenuation gap 424. The size of the attenuation gap 424 can vary based on the dimensions and relative positions of the light source 402, the reference sensor 406, the attenuation wall 422, the attenuation gap 424, the emission aperture 420, and other components of the optical rangefinder 400. For example, the attenuation wall depth 440, the attenuation wall length 441, the attenuation wall distance 442, the reference sensor distance 444, the emission lens distance 446, and the emission aperture diameter 448 can all affect the size and position of the attenuation gap 424.

[0072] The attenuation gap 424 is the gap between the distal end 422b of the attenuation wall 422 and an internal structure (e.g., EMI shield 430) or another surface closest to the distal end 422b of the attenuation wall 422. The attenuation gap 424 can be measured based on the widest portion of the attenuation gap 424, the narrowest portion of the attenuation gap 424, the average distance of the attenuation gap 424, or other similar measurement mechanisms. In some embodiments, the attenuation gap 424 is between 80 micrometers and 160 micrometers. More preferably, it is between 90 micrometers and 150 micrometers. Most preferably, it is between 100 micrometers and 140 micrometers.

[0073] The attenuation wall distance 442 represents the distance from the light radiation source 402 to the center of the attenuation wall 422. The attenuation wall distance 442 can be between 2.75 mm and 3.25 mm. More preferably, it is between 2.85 mm and 3.15 mm. Most preferably, it is between 2.95 mm and 3.05 mm.

[0074] The attenuation wall 422 may further include an attenuation wall depth 440 and an attenuation wall length 441. The attenuation wall depth 440 represents the distance from the light source side 422c of the attenuation wall 422 to the reference sensor side 422d of the attenuation wall 422. The attenuation wall depth 440 may be between 1.25 mm and 2.25 mm. More preferably, it is between 1.35 mm and 2.15 mm. Most preferably, it is between 1.5 mm and 2.0 mm.

[0075] The attenuation wall length 441 represents the distance from the attachment end 422a of the attenuation wall 422 to the distal end 422b of the attenuation wall 422. The attenuation wall length 441 may depend on the height of the housing cap 410 and / or the emission lens distance 446. In some embodiments, the attenuation wall length 441 is between 1.0 mm and 5.0 mm. More preferably, it is between 1.25 mm and 4.0 mm. Most preferably, it is between 1.5 mm and 3.0 mm.

[0076] like Figure 4As further described, the reference sensor distance 444 represents the distance from the reference sensor 406 to the light radiation source 402. In some embodiments, the reference sensor distance 444 is between 4.0 mm and 4.75 mm. More preferably, it is between 4.2 mm and 4.55 mm. Most preferably, it is between 4.25 mm and 4.5 mm.

[0077] like Figure 4 As further described, the emitting lens distance 446 represents the distance from the light radiation source 402 to the emitting lens 412a. In some embodiments, the emitting lens distance 446 is between 2.1 mm and 2.9 mm. More preferably, it is between 2.2 mm and 2.8 mm. Most preferably, it is between 2.25 mm and 2.75 mm.

[0078] like Figure 4 As further described, the emission opening diameter 448 represents the diameter of the emission opening 420. In some embodiments, the emission opening diameter 448 is between 1.5 mm and 2.5 mm. More preferably, it is between 1.6 mm and 2.4 mm. Most preferably, it is between 1.75 mm and 2.25 mm.

[0079] Example electronic system

[0080] Now for reference Figure 5 Several example electronic systems are provided, configured to use an optical range sensor 500 to determine the proximity of a target object. For example... Figure 5 As depicted, the housing cap 510 includes an attenuation wall 522 located within an emission cavity 503 between the light radiation source 502 and the reference sensor 506. The attenuation wall 522 defines an attenuation gap 524, allowing a portion of the emitted light radiation to reach the reference sensor 506 while blocking optical noise from reaching it. By blocking optical noise, the performance of the optical rangefinder 500 can be significantly improved without the need for an emission filter.

[0081] like Figure 5 Various electronic systems, including but not limited to mobile phones 550, wearable devices 552, consumer electronic devices 554, and industrial electronic devices 556, can benefit from utilizing the optical ranging sensor 500 according to embodiments described herein.

[0082] While this detailed description illustrates some embodiments of the present invention, the appended claims cover other embodiments of the present invention that differ from those described with various modifications and improvements. For example, those skilled in the art will recognize that such principles can be applied to any electronic device that uses a light source to determine the proximity and / or distance to a target object. Examples include mobile devices (such as telephones, tablets, and laptops); wearable electronic devices (such as watches and in-ear headphones); consumer electronics (such as robotic vacuum cleaners and projection systems); industrial electronic devices (such as drones, robots); and so on.

[0083] Within the appended claims, unless the specific terms “means for…” or “steps for…” are used within a given claim, the claims are not intended to be interpreted in accordance with paragraph 6 of 35 U.SC112.

[0084] The use of broad terms such as “comprising,” “including,” and “having” should be understood to provide support for narrower terms such as “consisting of,” “substantially consisting of,” and “truly consisting of.” The use of terms such as “optionally,” “may,” “possibly,” “possibly,” etc., relating to any element of the embodiment means that the element is not essential, or alternatively, that the element is essential, both substitutions being within the scope of the embodiment. Furthermore, references to examples are provided for illustrative purposes only and are not intended to be exclusive.

Claims

1. A housing cap for an optical distance measuring sensor, characterized in that The housing cap includes: a barrier wall defining: a launch cavity including: a light radiation source positioned to direct ranging light radiation toward a target object through a launch opening; a reference sensor positioned to receive a portion of the ranging light radiation; and an attenuation wall positioned between the light radiation source and the reference sensor defining an attenuation gap through which the portion of the ranging light radiation passes; and a receiving cavity including: a light radiation receiver positioned to receive ranging light radiation reflected from the target object through a receiver opening.

2. The case cap according to claim 1, characterized by Further comprising a top, wherein the launch opening and the receiver opening are defined by the top of the housing cap.

3. The case cap according to claim 2, characterized by The attenuation wall further includes an attachment end attached to the top of the housing cap and a distal end extending into the launch cavity.

4. The housing cap of claim 3, wherein, Wherein the top and the attenuation wall comprise a single continuous structure.

5. The case cap according to claim 4, characterized by Wherein the housing cap is formed by an injection molding process.

6. The housing cap of claim 3, wherein, Wherein the light radiation source is attached to a surface of the substrate.

7. The housing cap of claim 6, wherein, Wherein the attenuation gap comprises a fluid passageway between the distal end of the attenuation wall and the surface of the substrate.

8. The housing cap of claim 6, wherein, Further comprising an electromagnetic interference shield attached to the surface of the substrate and covering at least a portion of the light radiation source.

9. The case cap according to claim 8, characterized by Wherein the attenuation gap comprises a fluid passageway between the distal end of the attenuation wall and the electromagnetic interference shield.

10. The housing cap of claim 1, wherein, Wherein the barrier wall creates an optically impermeable barrier between the launch cavity and the receiving cavity.

11. The housing cap of claim 1, wherein, Wherein the attenuation wall blocks the reference sensor from receiving ambient light entering the launch opening.

12. The case cap of claim 1, wherein Wherein the attenuation gap is between 80 micrometers and 160 micrometers.

13. The case cap of claim 1, wherein Wherein an attenuation wall distance from the light radiation source to the attenuation wall is between 2.75 millimeters and 3.25 millimeters.

14. The housing cap of claim 1, wherein, Wherein the launch opening comprises a diameter between 1.75 millimeters and 2.25 millimeters.

15. The housing cap of claim 1, wherein, Further comprising a launch lens positioned in the launch opening.

16. The case cap of claim 15, wherein, Wherein a launch lens distance from the light radiation source to the launch lens is between 2.25 millimeters and 2.75 millimeters.

17. The housing cap of claim 1, wherein, Wherein a reference sensor distance defining a distance between the reference sensor and the light radiation source is between 4.25 millimeters and 4.5 millimeters.

18. An electronic system configured to determine a proximity of a target object, the system comprising: Comprising: an outer cover; and an optical ranging sensor arranged on an inner side of the outer cover opposite the target object, the optical ranging sensor comprising: a housing cap including a barrier wall defining: a launch cavity including: a light radiation source positioned to direct ranging light radiation toward a target object through a launch opening; a reference sensor positioned to receive a portion of the ranging light radiation; and an attenuation wall positioned between the light radiation source and the reference sensor defining an attenuation gap through which the portion of the ranging light radiation passes; and a receiving cavity including: a light radiation receiver positioned to receive ranging light radiation reflected from the target object through a receiver opening.

19. The electronic system of claim 18, wherein, The housing cap further comprises: a top defining the launch opening and the receiver opening, wherein the attenuation wall further includes an attachment end attached to the top of the housing cap and a distal end extending into the launch cavity.

20. The electronic system of claim 18, wherein, Wherein the attenuation gap is between 80 micrometers and 160 micrometers.

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