Abstract: A photographing lens system includes, in order from an object side to an image side along an optical path, a front lens group and a rear lens group. The front lens group includes four lens elements. The rear lens group includes four lens elements. A second lens element counted from the image side in the front lens group has negative refractive power. An image-side surface of a first lens element counted from the image side in the front lens group is convex in a paraxial region thereof. A second lens element counted from the object side in the rear lens group has negative refractive power. An object-side surface of a first lens element counted from the image side in the rear lens group is concave in a paraxial region thereof. At least one lens element in the rear lens group has at least one lens surface being aspheric.

Abstract: An electronic device includes at least two image capturing units which face the same side. The at least two image capturing units include a first image capturing unit and a second image capturing unit. The first image capturing unit includes an optical image system and a first image sensor. The optical image system includes a first lens element and an image surface. The first image sensor is disposed on the image surface of the optical image system thereof and has a first resolution of at least 60 megapixels. The second image capturing unit includes an optical image system and a second image sensor. The optical image system includes a first lens element and an image surface. The second image sensor is disposed on the image surface of the optical image system thereof and has a second resolution of at least 40 megapixels.

Abstract: An imaging optical lens system includes eight lens elements which are, in order from an object side to an image side along an optical path: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element. The first lens element has positive refractive power. The second lens element has negative refractive power. The seventh lens element has an image-side surface being concave in a paraxial region thereof, and the image-side surface of the seventh lens element has at least one convex critical point in an off-axis region thereof.

Abstract: An optical lens system includes six lens elements from an object side to an image side, the six lens elements are, in order from the object side to the image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. Each of the six lens elements has an object-side surface towards the object side and an image-side surface towards the image side. The image-side surface of the second lens element is concave in a paraxial region thereof. The third lens element has positive refractive power. The image-side surface of the fourth lens element is concave in a paraxial region thereof. The image-side surface of the sixth lens element includes at least one inflection point.

Abstract: An imaging lens system includes four lens elements which are, in order from an object side to an image side: a first lens element, a second lens element, a third lens element and a fourth lens element, and each of the four lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has negative refractive power. The fourth lens element has positive refractive power, and the image-side surface of the fourth lens element is convex in a paraxial region thereof. At least one lens element of the imaging lens system has at least one lens surface having at least one inflection point.

Abstract: An optical photographing lens assembly includes six lens elements which are, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element. Each of the six lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has positive refractive power. The fourth lens element has positive refractive power. The image-side surface of the fourth lens element is convex in a paraxial region thereof. The image-side surface of the fifth lens element is concave in a paraxial region thereof. The sixth lens element has negative refractive power. The object-side surface of the sixth lens element is convex in a paraxial region thereof.

Abstract: An imaging optical lens system includes eight lens elements which are, in order from an object side to an image side along an optical path: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element. The first lens element has positive refractive power. The second lens element has negative refractive power. The seventh lens element has an image-side surface being concave in a paraxial region thereof, and the image-side surface of the seventh lens element has at least one convex critical point in an off-axis region thereof.

Abstract: An optical photographing lens includes two lens groups including six lens elements. The two lens groups are, in order from an object side to an image side, a first and a second lens groups. The six lens elements are, in order from the object side to the image side, a first lens element through a sixth lens element. A focal length adjusting process is performed by changing an axial distance between the lens groups for varying a focal length of the optical photographing lens. The second lens group moves relative to the first lens group during the focal length adjusting process. At least one lens surface of the optical photographing lens has at least one inflection point always located within an optically effective area during the focal length adjusting process. The second lens element has negative refractive power.

Abstract: A photographing lens assembly includes five lens elements which are, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. Each of the five lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has positive refractive power. The third lens element has negative refractive power, the object-side surface of the third lens element is convex in a paraxial region thereof, and the image-side surface of the third lens element is concave in a paraxial region thereof. At least one of the object-side surface and the image-side surface of at least one lens element of the photographing lens assembly is aspheric.

Abstract: An optical photographing system includes seven lens elements which are, in order from an object side to an image side along an optical path: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. Each of the seven lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The object-side surface of the sixth lens element is convex in a paraxial region thereof. At least one of the object-side surface and the image-side surface of at least one lens element of the optical photographing system has at least one inflection point.

Abstract: An optical image lens assembly includes five lens elements which are, in order from an object side to an image side along an optical path: a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. Each of the five lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The object-side surface of the first lens element is convex in a paraxial region thereof. The image-side surface of the third lens element is concave in a paraxial region thereof. The object-side surface of the fourth lens element is concave in a paraxial region thereof, and the image-side surface of the fourth lens element is convex in a paraxial region thereof.

Abstract: A photographing optical lens assembly includes seven lens elements, the seven lens elements being, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. Each of the seven lens elements includes an object-side surface facing towards the object side and an image-side surface facing towards the image side. The image-side surface of the seventh lens element is concave in a paraxial region thereof and includes at least one inflection point in an off-axis region thereof.

Abstract: An imaging lens system includes seven lens elements which are, in order from an object side to an image side along an optical path, a first lens element through a seventh lens element. Each of the seven lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The image-side surface of the sixth lens element is concave in a paraxial region thereof. The object-side surface of the seventh lens element is concave in a paraxial region thereof. At least one of the object-side surface and the image-side surface of at least one of the seven lens elements has at least one inflection point in an off-axis region thereof.

Abstract: An image lens assembly includes four lens groups: a first lens group, a second lens group, a third lens group and a fourth lens group along an optical path. The four lens groups include nine lens elements: a first lens element with positive refractive power, a second lens element with negative refractive power, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element, an eighth lens element and a ninth lens element along the optical path. At least one lens element of the image lens assembly has at least one inflection point. At least five lens elements of the image lens assembly are made of plastic material. When focusing or zooming, the first lens group and the fourth lens group stay stationary, while the second lens group and the third lens group move along an optical axis.

Abstract: A photographing system lens assembly includes eight lens elements, the eight lens elements being, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element. Each of the eight lens elements has an object-side surface towards the object side and an image-side surface towards the image side.

Abstract: A photographing optical system includes eight lens elements which are, in order from an object side to an image side: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element. The eight lens elements each have an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has positive refractive power. The fifth lens element has positive refractive power. The object-side surface of the seventh lens element is convex in a paraxial region thereof. The image-side surface of the eighth lens element is concave in a paraxial region thereof. At least one lens surface of at least one lens element of the photographing optical system has at least one critical point in an off-axis region thereof.

Abstract: A method of spectroscopic analysis includes: collecting a set of calibration spectra for calibration gas samples by scanning a sample range of wavelengths; calculating a first concentration of a target analyte and first concentrations of background components for each calibration spectrum using a multivariant algorithm; modeling an ideal concentration of the target analyte as a function of the first concentrations using a correlative model; collecting a field spectrum for an unknown field gas sample, wherein the field gas sample includes the target analyte and at least some of the background components; calculating a second concentration of the target analyte and second concentrations the background components for the field spectrum using the multivariant algorithm; correcting the second concentration of the target analyte using the correlative model and second concentrations of the background components; and determining a corrected target analyte concentration in the field gas sample based on the corrected s

Abstract: An optical imaging system includes six lens elements which are, in order from an object side to an image side along an optical path: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. Each of the six lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has negative refractive power, and the object-side surface of the first lens element is concave in a paraxial region thereof. The image-side surface of the second lens element is concave in a paraxial region thereof. The fourth lens element has negative refractive power. The image-side surface of the sixth lens element is concave in a paraxial region thereof and has at least one critical point in an off-axis region thereof.

Abstract: An image capturing optical lens system includes four lens elements, which are, in order from an object side to an image side along an optical path, a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element has an object-side surface being convex in a paraxial region thereof. The third lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof. The fourth lens element has negative refractive power.

Abstract: A photographing optical system includes eight lens elements which are, in order from an object side to an image side: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element, a seventh lens element and an eighth lens element. The eight lens elements each have an object-side surface facing toward the object side and an image-side surface facing toward the image side. The first lens element has positive refractive power. The fifth lens element has positive refractive power. The object-side surface of the seventh lens element is convex in a paraxial region thereof. The image-side surface of the eighth lens element is concave in a paraxial region thereof. At least one lens surface of at least one lens element of the photographing optical system has at least one critical point in an off-axis region thereof.