Abstract: An optical imaging system is provided. The optical imaging system includes, in order from an object side to an image side along an optical axis: the first lens, the second lens, the third lens, the fourth lens, and the fifth lens. The optical imaging system satisfies the following expression: 0.5<(|SAG51|+SAG52)/CT5<3.5, where SAG51 represents a distance from an intersection of the object-side surface of the fifth lens and the optical axis to a projection of an edge of an optical effective area of the object-side surface of the fifth lens on the optical axis, SAG52 represents a distance from an intersection of the image-side surface of the fifth lens and the optical axis to a projection of an edge of an optical effective area of the image-side surface of the fifth lens on the optical axis, and CT5 represents a center thickness of the fifth lens on the optical axis.

Abstract: An optical system, a lens module, and an electronic device are provided. The optical system includes, in order from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens with, and a seventh lens. The first lens has an object-side surface which is convex at an optical axis and an image-side surface which is concave at the optical axis and at a circumference. The second lens has an object-side surface which is convex at the optical axis and an image-side surface which is concave at the optical axis and at a circumference. The seventh lens has an image-side surface, which is concave at the optical axis and has at least one inflection point. The optical system satisfies the following expression: f/EPD<1.7.

Abstract: An optical system, a lens module, and an electronic device are provided. The optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens. The fifth lens has an object-side surface and an image-side surface which are both aspheric surfaces. At least one of the object-side surface and the image-side surface of the fifth lens has at least one inflection point. The sixth lens has an object-side surface and an image-side surface which are both aspheric surfaces. At least one of the object-side surface and the image-side surface of the sixth lens has at least one inflection point.

Abstract: An optical system is provided. The optical system includes a first lens with a positive refractive power, where the first lens has an object-side surface which is convex near the optical axis and an image-side surface which is concave near the optical axis; a second lens with a negative refractive power, where the second lens has an object-side surface which is convex near the optical axis and an image-side surface which is concave near the optical axis; a third lens with a refractive power; a fourth lens with a positive refractive power; a fifth lens with a refractive power; a sixth lens with a refractive power, where the sixth lens has an object-side surface which is concave near the optical axis; and a seventh lens with a negative refractive power, where the seventh lens has an object-side surface which is convex near the optical axis and an image-side surface.

Abstract: An optical system, a lens module, and an electronic device are provide. The optical system includes, in order from an object side to an image side along an optical axis, a first lens with a negative refractive power, a second lens with a positive refractive power, a third lens with a negative refractive power, a fourth lens with a refractive power, a fifth lens with a positive refractive power, and a sixth lens with a negative refractive power. An object-side surface of the fifth lens has at least one inflection point. At least one of an object-side surface and an image-side surface of the sixth lens has at least one inflection point. The optical system satisfies the following expression: ?9<f4/|f1|<3.5.