Abstract: A time synchronization method includes obtaining a first BLUETOOTH packet from a master device, where the first BLUETOOTH packet carries first time stamp information, and the first time stamp information indicates a sending moment t1 that is of the first BLUETOOTH packet and that is determined based on a clock of the master device; and correcting a local time of a slave device based on the first time stamp information.

Abstract: A semiconductor laser, an optical transmitter component, an optical line terminal, and an optical network unit. The semiconductor laser includes a substrate, a lower waveguide layer, a lower confining layer, a central layer, an upper confining layer, a grating layer, an upper waveguide layer, and an electrode layer that are sequentially formed on the substrate. The upper confining layer, the central layer, and the lower confining layer in a filtering region form a core layer of the filtering region. The grating layer in the filtering region includes a slanted grating. Thus, a modulation chirp and dispersion of a transmitted optical pulse can be reduced.

Abstract: The disclosure describes a light-emitting diode (LED) display device with a control circuit layer, multiple electrodes, multiple LEDs, and a common electrode layer. The control circuit layer is coupled with multiple scan lines and data lines, with the scan lines and data lines intersecting substantially perpendicularly. The electrodes are positioned on the control circuit layer and coupled to the control circuit layer, with all electrodes electrically isolated. The LEDs are respectively placed on the electrodes and are coupled to them, arranged in an array. The common electrode layer comprises multiple equivalent one-dimensional (1D) electrode strips. The different ends of the equivalent 1D electrode strips connect to a supply voltage. The equivalent 1D electrode strips are respectively placed on multiple columns of the LED array and are coupled to multiple columns of the LED array, intersecting the scan lines substantially perpendicularly.

Abstract: A light-emitting device driving circuit includes: a voltage conversion circuit, at least one light-emitting device, a current driving circuit, and a controller. Any light-emitting device and the current driving circuit are coupled in series between an output terminal and a ground terminal of the voltage conversion circuit. The controller is configured to output a first control signal to the current driving circuit, the current driving circuit is configured to provide a predetermined current for a first light-emitting device based on the first control signal, the controller is configured to output a second control signal to the voltage conversion circuit based on an electrical parameter on a path on which the first light-emitting device and the current driving circuit are located, and the voltage conversion circuit is configured to adjust a voltage at the output terminal of the voltage conversion circuit based on the second control signal.

Abstract: A blood pressure measurement device and an electronic device are provided. The blood pressure measurement device includes a body (1), a processor (7), an airbag (2), an air supply and exhaust apparatus (4), a driving apparatus (6), a barometric pressure sensor (5), and a flowmeter (9). The body (1) includes a cavity (101), the airbag (2) has an air cavity, and the airbag (2) is fastened to an end of the body (1). The air supply and exhaust apparatus (4) is connected to the air cavity of the airbag (2) through a first air path (81). The barometric pressure sensor (5) is connected to the air cavity of the airbag (2) through a second air path (82). The flowmeter (9) is configured to detect an air flow value between the air supply and exhaust apparatus (4) and the airbag (2), or is configured to detect an air flow value between the barometric pressure sensor (5) and the airbag (2).

Abstract: This application provides example Fresnel membranes. One example Fresnel membrane includes a substrate and Fresnel teeth located on a surface of the substrate. The Fresnel membrane further includes a through-hole that is provided in a thickness direction of the Fresnel membrane and runs through the substrate and the Fresnel teeth. The through-hole extends to form a closed circle. The Fresnel membrane further includes light-shielding ink that is stuffed in the through-hole. The light-shielding ink divides the Fresnel membrane into two regions that are spaced apart from each other.

Abstract: A display panel includes a substrate, a photoelectric detector, and a display surface. The photoelectric detector is located on a side that is of the substrate and that is close to the display surface. The photoelectric detector includes a PN junction or a PIN junction. The photoelectric detector is configured to be reverse biased or zero biased when the display apparatus works in an ambient light detection stage to generate a photo-generated current under illumination of ambient light and detect ambient light information. The photoelectric detector is disposed above the substrate, and ambient light needs to penetrate only a part of a film layer structure of the display panel to be received by the photoelectric detector.

Abstract: This application provides examples of an optical measurement apparatus, a bandpass filter, an optical measurement method, and an electronic device. An example optical measurement apparatus includes a light source emitting assembly, a bandpass filter, and a receiving and measuring assembly. The bandpass filter is disposed between a to-be-measured object and the receiving and measuring assembly. An optical filter spectrum band of the bandpass filter includes a light source operating spectrum band of the light source emitting assembly. The light source emitting assembly is configured to emit first detection light to the to-be-measured object. The bandpass filter is configured to emit third detection light to the receiving and measuring assembly based on second detection light. The second detection light includes light reflected or transmitted by the to-be-measured object based on the first detection light.

Abstract: A light-emitting device driving circuit includes: a voltage conversion circuit, at least one light-emitting device, a current driving circuit, and a controller. Any light-emitting device and the current driving circuit are coupled in series between an output terminal and a ground terminal of the voltage conversion circuit. The controller is configured to output a first control signal to the current driving circuit, the current driving circuit is configured to provide a predetermined current for a first light-emitting device based on the first control signal, the controller is configured to output a second control signal to the voltage conversion circuit based on an electrical parameter on a path on which the first light-emitting device and the current driving circuit are located, and the voltage conversion circuit is configured to adjust a voltage at the output terminal of the voltage conversion circuit based on the second control signal.

Abstract: A time synchronization method includes obtaining a first BLUETOOTH packet from a master device, where the first BLUETOOTH packet carries first time stamp information, and the first time stamp information indicates a sending moment t1 that is of the first BLUETOOTH packet and that is determined based on a clock of the master device; and correcting a local time of a slave device based on the first time stamp information.

Abstract: A receiver optical sub-assembly, a combo bi-directional optical sub-assembly, a combo optical module, an optical line terminal, and a passive optical network system, where the receiver optical sub-assembly includes a first transistor-outline can, where a light incident hole is disposed on the first transistor-outline can, and where a first demultiplexer, a first optical receiver, a second optical receiver, and an optical lens combination are packaged in the first transistor-outline can.

Abstract: An electronic device includes a body and a PPG sensor. The PPG sensor includes: a substrate, a first electrode, a light emitting layer, a light receiving layer, a second transparent electrode, and a transparent panel that are integrally packaged. The substrate and the first electrode are both located on one side of the light emitting layer, and the second transparent electrode and the transparent panel are both located on the other side of the light emitting layer. The light receiving layer, the first electrode, and the second transparent electrode are all located between the substrate and the transparent panel, and a polarity of the first electrode and a polarity of the second transparent electrode are opposite. The light emitting layer includes a light emitting pixel for emitting an optical signal, and the light receiving layer includes a light receiving pixel for detecting the optical signal.

Abstract: A display panel includes a substrate, a photoelectric detector, and a display surface. The photoelectric detector is located on a side that is of the substrate and that is close to the display surface. The photoelectric detector includes a PN junction or a PIN junction. The photoelectric detector is configured to be reverse biased or zero biased when the display apparatus works in an ambient light detection stage to generate a photo-generated current under illumination of ambient light and detect ambient light information. The photoelectric detector is disposed above the substrate, and ambient light needs to penetrate only a part of a film layer structure of the display panel to be received by the photoelectric detector.

Abstract: A receiver optical sub-assembly, a combo bi-directional optical sub-assembly, a combo optical module, an optical line terminal, and a passive optical network system, where the receiver optical sub-assembly includes a first transistor-outline can, where a light incident hole is disposed on the first transistor-outline can, and where a first demultiplexer, a first optical receiver, a second optical receiver, and an optical lens combination are packaged in the first transistor-outline can.

Abstract: An electronic device includes a first optical transmitter, a second optical transmitter, a first optical receiver, and a second optical receiver. The first optical transmitter and the second optical transmitter may respectively transmit a first optical signal and a second optical signal with different wavelengths to a skin surface of a user. The first optical receiver may generate a first PPG signal based on a received first optical signal. The second optical receiver may generate a second PPG signal based on the received second optical signal. The second PPG signal may be used to determine a magnitude of noise in the first PPG signal.

Abstract: An optical transmitter includes a light source and an adjustment structure. The light source is configured to output an original light spot, to transmit a test optical signal to a skin of a user. The adjustment structure is located on an output optical path of the test optical signal.

Abstract: A receiver optical sub-assembly, a combo bi-directional optical sub-assembly, a combo optical module, an optical line terminal, and a passive optical network system, where the receiver optical sub-assembly includes a first transistor-outline can, where a light incident hole is disposed on the first transistor-outline can, and where a first demultiplexer, a first optical receiver, a second optical receiver, and an optical lens combination are packaged in the first transistor-outline can.

Abstract: A transmitter optical subassembly is disclosed including a substrate and a direct modulated laser disposed on the substrate. A single-stage isolator, a polarization direction rotator, and an optical branching filter are disposed side by side on the substrate in a light propagation direction. The polarization direction rotator can adjust linearly polarized light to P-polarized light, the optical branching filter includes an optical splitter subassembly and a filter subassembly, and an optical splitter film in the optical splitter subassembly is an optical splitter film with P polarization. The polarization direction rotator adjusts the incident linearly polarized light to the P-polarized light, and the optical splitter film in the optical branching filter is the optical splitter film with P polarization; all P-polarized light with single polarization can pass through the optical branching filter, without causing any polarization loss or two peaks.

Abstract: A receiver optical sub-assembly, a combo bi-directional optical sub-assembly, a combo optical module, an optical line terminal, and a passive optical network system, where the receiver optical sub-assembly includes a first transistor-outline can, where a light incident hole is disposed on the first transistor-outline can, and where a first demultiplexer, a first optical receiver, a second optical receiver, and an optical lens combination are packaged in the first transistor-outline can.

Abstract: A semiconductor laser, an optical transmitter component, an optical line terminal, and an optical network unit. The semiconductor laser includes a substrate, a lower waveguide layer, a lower confining layer, a central layer, an upper confining layer, a grating layer, an upper waveguide layer, and an electrode layer that are sequentially formed on the substrate. The upper confining layer, the central layer, and the lower confining layer in a filtering region form a core layer of the filtering region. The grating layer in the filtering region includes a slanted grating. Thus, a modulation chirp and dispersion of a transmitted optical pulse can be reduced.