The present application is related to optical sensors, and in particular an electronic device that uses optical sensors with at least two wavelength bands to detect the presence of an object.
Optical sensors are being used in many systems, such as smartphones, wearable electronics, robotics, and autonomous vehicles, etc. for proximity detection, 2D/3D imaging, object recognition, image enhancement, material recognition, color fusion, health monitoring, and other relevant applications. In some scenarios, the optical sensor is operated to detect the proximity to the object. Accordingly, it is challenging for the accuracy of detection.
The present disclosure discloses an electronic device with an optical sensing apparatus which utilizes one or more optical detectors with at least two wavelength bands to detect the presence of an object. In this way, the electronic device with the optical sensing apparatus can switch its various functions in a smarter way according to the detection result. The optical sensing apparatus can be operable for different wavelength ranges, including visible light (e.g., wavelength range 380 nm to 780 nm, or a similar wavelength range as defined by a particular application) and non-visible light. The non-visible light includes near-infrared (NIR, e.g., wavelength range from 780 nm to 1400 nm, or a similar wavelength range as defined by a particular application) and short-wavelength infrared (SWIR, e.g., wavelength range from 1400 nm to 3000 nm, or a similar wavelength range as defined by a particular application) light.
When the electronic device is used multiple times or placed in different environments, contaminants may appear on the surface of the optical sensing apparatus or electronic device. When the electronic device is worn on the user, contaminants may interfere with the measured reflected light. Therefore, the information of presence of an object detected by the electronic device may be inaccurate, thereby affecting the user experience. It would be desirable for the electronic device to dynamically calibrate the threshold depending on the condition of the electronic device.
Optical sensors can emit light and receive reflected light. When an object is not present, the electronic device can use reflected light to detect contaminants on optical sensors. Based on these detected contaminants, distance thresholds for detecting an object with the optical sensor (e.g., detecting a user) can be adjusted to enable the electronic device to properly detect objects via the optical sensors despite the presence of these contaminants.
Aspects of the present disclosure are described herein.
One aspect of the present disclosure is directed to an optical sensing apparatus configured to detect an object. The apparatus includes a light receiver configured to receive at least two lights with a first wavelength and a second wavelength. The apparatus also includes a memory configured to store a plurality of adjusting parameters, and a processor configured to compare a first reference light intensity at the first wavelength and a second reference light intensity at the second wavelength without a presence of the object to obtain a condition index, access a corresponding adjusting parameter from the memory according to the condition index for adjusting a threshold, and compare a reflected light intensity reflected from the object with the adjusted threshold to determine a detection information.
In some implementations, the optical sensing apparatus further includes a light transmitter configured to emit at least two lights with the first wavelength and the second wavelength.
In some implementations, the light receiver includes a first photoelectronic device configured to receive a first light with the first wavelength and a second photoelectronic device configured to receive a second light with the second wavelength.
In some implementations, the second wavelength is larger than the first wavelength.
In some implementations, the processor indicates the detection information as close distance when the reflected light intensity is greater than the adjusted threshold.
In some implementations, the processor is configured to adjust another threshold by the corresponding adjusting parameter and indicate the detection information as far distance when the reflected light intensity is less than the adjusted another threshold.
In some implementations, the adjusted threshold is determined by multiplying corresponding adjusting parameter by the threshold.
In some implementations, the first wavelength is in a range of NIR light, the second wavelength is in a range of SWIR light.
In some implementations, the condition index is obtained by calculating a ratio of the first reference light intensity to the second reference light intensity.
In some implementations, the memory includes a look-up table used to store a plurality of adjusting parameters.
In some implementations, the optical sensing apparatus further includes a housing in which the light receiver, the memory, and the processor are accommodated.
In some implementations, the processor is implemented by digital processor, application-specific integrated circuit, digital circuitry, or software module.
Another aspect of the present disclosure is directed to an electronic device. The electronic device includes, including the optical sensing apparatus described above, wherein the electronic device can operate in normal operating mode or power saving mode according to the detection information.
In some implementations, the electronic device is an earphone, a wristwatch, or a head-mount device.
Another aspect of the present disclosure is directed to a method of indicating a detection information by an optical sensing apparatus. The method includes receiving a first reference light intensity at a first wavelength and a second reference light intensity at the second wavelength at a first time without a presence of the object by a light receiver, comparing the first reference light intensity and the second reference light intensity to obtain a condition index by a processor, and accessing a corresponding adjusting parameter from a memory according to the condition index for adjusting thresholds, and comparing a reflected light intensity with the adjusted thresholds to determine a detection information.
In some implementations, the corresponding adjusting parameter is accessed from a lookup table stored in the memory.
In some implementations, the method includes transmitting a testing light with the first wavelength to the object by a light transmitter, wherein a portion of testing light is reflected from the object toward the light receiver.
In some implementations, the condition index is obtained by calculating a ratio of the first reference light intensity to the second reference light intensity.
In some implementations, the processor indicates different detection information according to different adjusted thresholds.
In some implementations, the optical sensing apparatus is included in an electronic device, wherein the electronic device is an earphone, a wristwatch, or a head-mount device.
The foregoing aspects and many of the advantages of this application will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings:
The following embodiments accompany the drawings to illustrate the concept of the present disclosure. In the drawings or descriptions, similar or identical parts use the same reference numerals, and in the drawings, the shape, thickness or height of the element is can be reasonably expanded or reduced. The embodiments listed in the present application are only used to illustrate the present application and are not used to limit the scope of the present application. Any obvious modification or change made to the present application does not depart from the spirit and scope of the present application.
An electronic device (e.g., earphones, AR/VR wearable equipment, etc.) has a plurality of functions and/or a plurality of operating modes. When the electronic device is worn on the user or removed from the user, it can operate in different operating modes to meet the user's experience. For example, when the electronic device is removed from the user, it can operate in a power saving mode. When the electronic device is worn on the user, it can operate in a normal operating mode. An optical sensing apparatus can be arranged on the electronic device to receive the reflected light from the user, and compare the reflected light intensity with a threshold to determine whether the electronic device is worn on the user. When the electronic device is used multiple times or placed in different environments, contaminants may appear on the surface of the optical sensing apparatus or electronic device. When the electronic device is worn on the user, contaminants may interfere with the measured reflected light. Therefore, the information of presence of an object detected by the electronic device may be inaccurate, thereby affecting the user experience. It would be desirable for the electronic device to dynamically calibrate the threshold depending on the condition of the electronic device.
The light receiver 2 includes a multi-band optic detector and is configured to receive at least two lights at different wavelengths which correspond to the lights emitted from the light transmitter 3. The processor 4 is coupled to the light receiver 2 and the light transmitter 3. The memory 5 is coupled to the processor 4. The memory 5 includes a look-up table to store a plurality of adjusting parameters for dynamically adjusting thresholds.
The processor 4 is configured to control the activation of the optical receiver 2 and the optical transmitter 3, process the received light intensity from the optical receiver 2, access the adjusting parameters from the memory 5, dynamically adjust the thresholds to indicate the object detection.
The light receiver 2 can include a single photoelectronic device or a plurality of photoelectronic devices arranged in an array. In an embodiment, the light receiver 2 includes a plurality of photoelectronic devices configured to receive a plurality of lights with different wavelengths. In another embodiment, the light receiver 2 can include an electronic component electrically connected to the photoelectronic device for transmitting signal or providing power. The electronic component can include resistor, capacitor, inductor, or integrated circuit (IC). The photoelectronic device can include a supporting substrate and a detecting region supported by the supporting substrate. The detecting region can include germanium (Ge) or a material compound in the III-V group (e.g., GaAs), and is configured to absorb photons. The supporting substrate can include a material, such as silicon, different from that of the detecting region. The light receiver 2 can detect the visible light, or the non-visible light according to the application. The visible light can include blue, navy, green, yellow, or red light. The non-visible light can include NIR or SWIR.
The light transmitter 3 can be a semiconductor light-emitting element, such as a light-emitting diode (LED), a laser diode, or organic light-emitting diode (OLED). The light transmitter 3 can emit a light corresponding to the detecting wavelength of the light receiver 2. The processor 4 can be implemented by digital processor (DSP), general purpose processor, application-specific integrated circuit (ASIC), digital circuitry, software module, or any combinations thereof.
When the outer surface of the optical sensing apparatus 10 is covered by different contaminations, the received light intensity at D1, D2 will vary with different contaminations. If the threshold is not calibrated, the distance D1, D2 might vary with different contaminations, which would yield undesirable user experience. For example, if the processor 4 uses the fixed default thresholds THM0(D1), THM0(D2) to compare with the reflected light intensity, the processor 4 under condition M1 would not output the detection result as “ON” at D1 because the received light intensity cannot reach THM0(D1). Therefore, the electronic device 100 cannot correctly detect the presence of the object and switch to the correct operating mode. To help avoid inaccurate detection information, it is desirable for the processor 4 to dynamically adjust the thresholds with the different contaminations. For example, if the contamination M2 covers on the electronic device 100, the processor 4 should dynamically adjust the default thresholds THM0(D1), THM0(D2) to be THM2(D1), THM2(D2) for comparing with the reflected light intensity to obtain the accurate detection information. As shown in
As shown in
While the disclosure has been described by way of example and in terms of a preferred embodiment, it is to be understood that the disclosure is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
This patent application claims priority to Provisional Patent Application No. 63/410,235, filed Sep. 27, 2022, the contents of which are incorporated herein by reference in their entirety.
Number | Date | Country | |
---|---|---|---|
63410235 | Sep 2022 | US |