Abstract: The disclosure provides a data privacy protection method, a server device, and a client device for federated learning. A public dataset is used to perform model training on a machine learning model by a server device to generate a gradient pool including multiple first gradients. The gradient pool and the machine learning model are received by a client device. The client device uses a local dataset to perform model training on the machine learning model to obtain a second gradient. A local gradient is selected from the first gradients in the gradient pool according to the second gradient using a differential privacy algorithm by the client device. An aggregated machine learning model is generated by performing model aggregation based on the local gradient by the server device.

Abstract: A compact optical imaging device with short optical length and low sensitivity, for use in an imaging module and an electronic device, comprises first to fifth lenses and a filter. An image-side surface of the fourth lens is convex near an optical axis of the optical imaging device. An image-side surface of the fifth lens is concave near the optical axis. The optical imaging device satisfies formulas 0.03 mm/°<TL5/FOV<0.1 mm/° and 2.4 mm<TL4/FNO<2.9 mm, TL5 being a distance from an object-side surface of the fifth lens to an image plane of the optical imaging device along the optical axis, FOV being a maximum field of view, TL4 being a distance from an object-side surface of the fourth lens to the image plane along the optical axis, and FNO being a F-number of the optical imaging device.

Abstract: A semiconductor structure includes a substrate, a channel region, a gate structure, and source/drain regions. The channel region is over the substrate. The gate structure is over the channel region, and includes a high-k dielectric layer, a tungsten layer over the high-k dielectric layer, and a fluorine-containing work function layer over the tungsten layer. The source/drain regions are at opposite sides of the channel region.

Abstract: A compact optical imaging device with short optical length and low sensitivity, for use in an imaging module and an electronic device, comprises first to fifth lenses and a filter. An image-side surface of the fourth lens is convex near an optical axis of the optical imaging device. An image-side surface of the fifth lens is concave near the optical axis. The optical imaging device satisfies formulas 0.03 mm/°<TL5/FOV<0.1 mm/° and 2.4 mm<TL4/FNO<2.9 mm, TL5 being a distance from an object-side surface of the fifth lens to an image plane of the optical imaging device along the optical axis, FOV being a maximum field of view, TL4 being a distance from an object-side surface of the fourth lens to the image plane along the optical axis, and FNO being a F-number of the optical imaging device.

Abstract: A compact optical imaging device with shortened focal length, for use in an imaging module and an electronic device, comprises first to fifth lenses. An image-side surface of the first lens is concave near an optical axis. An image-side surface of the third lens is concave near the optical axis. The second and fourth lenses have a negative refractive power. The third and fifth lenses have a positive refractive power. The optical imaging device satisfies formulas: 95°/mm<FOV/TL5<105°/mm and 1 mm?1<FNO/TL4<1.5 mm?1, FOV being a maximum field of view of the optical imaging device, TL5 being a distance from an object-side surface of the fifth lens to an image plane of the optical imaging device along the optical axis, FNO being a F-number of the optical imaging device, and TL4 being a distance from an object-side surface of the fourth lens to the image plane along the optical axis.

Abstract: An optical imaging lens proofed against field curvatures, in an imaging module, and the module being used in an electronic device, is, from an object side to an image side, composed of a first lens with a positive refractive power, a second lens, a third lens, a fourth lens with a negative refractive power, a fifth lens, and a sixth lens with a negative refractive power. The optical imaging lens satisfies the formula ?3 mm?1<FNO/f6<?0.1 mm?1, ?0.065 mm/°<f6/FOV<?0.03 mm/°, wherein FNO is a F-number of the optical imaging lens, f6 is a focal length of the sixth lens, and FOV is a maximum field of view of the optical imaging lens.

Abstract: A compact optical imaging device with three individual lenses, able to capture clear images of both near and distant objects with a balance between imaging quality and sensitivity, and used in an imaging module and an electronic device, satisfies the formula 0 mm<R11<1 mm, ?5%<DIS<5%, V1?V2, V3?V2, where R11 is a radius of curvature of an object-side surface of the first lens, DIS is optical distortion of the optical imaging device, V1 is a dispersion coefficient of the first lens, V2 is a dispersion coefficient of the second lens, and V3 is a dispersion coefficient of the third lens.

Abstract: A compact optical imaging device with short optical length and low sensitivity, for use in an imaging module and an electronic device, comprises first to fifth lenses and a filter. An image-side surface of the fourth lens is convex near an optical axis of the optical imaging device. An image-side surface of the fifth lens is concave near the optical axis. The optical imaging device satisfies formulas 0.03 mm/°<TL5/FOV<0.1 mm/° and 2.4 mm<TL4/FNO<2.9 mm, TL5 being a distance from an object-side surface of the fifth lens to an image plane of the optical imaging device along the optical axis, FOV being a maximum field of view, TL4 being a distance from an object-side surface of the fourth lens to the image plane along the optical axis, and FNO being a F-number of the optical imaging device.

Abstract: An optical imaging lens is composed of a first lens, a second lens having a positive refractive power, a third lens having a negative refractive power, a fourth lens, a fifth lens having a positive refractive power, and a sixth lens having a negative refractive power. At least one of the object surface of the fifth lens, the image surface of the fifth lens, the object surface of the sixth lens, and the image surface of the sixth lens is aspheric, having at least one critical point near the optical axis. The optical imaging lens meets formula 50<V6<60, 2<TTL/EPD<3, V6 being the dispersion coefficient of the sixth lens, TTL being the distance from the side of the first lens to the image surface of the optical imaging lens on the optical axis, and EPD being the entrance pupil diameter of the optical imaging lens.

Abstract: An optical imaging lens, an imaging module, and an electronic device are provided. The optical imaging lens, from an object side to an image side, is composed of a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. The optical imaging lens satisfies following formula: 24<(V5?V4)/(TL5?TL4)<42, 48<FOV/FNO<52. Wherein V4 is a dispersion coefficient of the fourth lens, V5 is a dispersion coefficient of the fifth lens, TL4 is a distance from an object surface of the fourth lens to an image plane of the optical imaging lens along an optical axis, TL5 is a distance from an object surface of the fifth lens to the image plane along the optical axis, FOV is a field of view of the optical imaging lens, and FNO is F-number of the optical imaging lens.

Abstract: A lens assembly has an optical axis. The lens assembly includes a first lens and a second lens stacked on a side of the first lens along the optical axis. A mounting groove is recessed from a surface of the first lens facing the second lens, the mounting groove is arranged around the optical axis and coaxially with the first lens. A protruding portion is protruded from a surface of the second lens facing the first lens to match the mounting groove, the protruding portion is arranged around the optical axis and coaxially with the second lens. The protruding portion is received in the mounting groove. The disclosure also provides an electronic device having the lens assembly.