Abstract: An optical system includes a first lens unit having positive refractive power, a second lens unit, and a third lens unit having negative refractive power arranged in order from an object side to an image side. The second lens unit moves in focusing, thereby changing a distance between adjacent lens units. The first lens unit includes a positive lens, and the third lens unit includes a negative lens. A focal length of the positive lens, a focal length of the negative lens, a focal length of the third lens unit, and a back focus of the optical system are appropriately set.

Abstract: An optical system is constituted of a first lens unit having a positive refractive power, a second lens unit having a positive refractive power and moving when focusing is performed, and a third lens unit which are arranged in this order from an object side to an image side, and distances between neighboring lens units are changed when focusing is performed. In the optical system, a back focus, arrangement of the second lens unit, and the like are appropriately set.

Abstract: An optical system includes a first lens unit B1 having a positive refractive power, a second lens unit B2, and a third lens unit B3 disposed in order from an object side to an image side. The second lens unit B2 moves in focusing so that an interval between adjacent lens units among the first, second, and third lens units changes. The first lens unit B1 includes a positive lens G1p disposed closest to the object side and a negative lens G1n being a closest negative lens with respect to the object side. The optical system satisfies a predetermined condition.

Abstract: An electric vehicle includes drive systems, a control apparatus that controls the drive systems, and wheels. Each drive system includes a motor and an inverter coupled by wires. The wires of the drive systems are coupled by first bypass lines. Each inverter converts direct current power supplied from a corresponding power supply into alternating current power and supplies the alternating current power to the corresponding motor. Each motor drives the corresponding wheel. When an abnormality occurs in the supply of the alternating current power from the inverter to the motor in one drive system, the control apparatus performs control (i) to stop the supply of the alternating current power from the inverter of the one drive systems, and (ii) to supply the alternating current power supplied from the inverter to the motor in another drive system, to the motor of the one drive system via the first bypass lines.

Abstract: An optical system used in an imaging apparatus includes an optical element. In a case where the optical element is disposed on a magnification side with respect to an intersection point of an optical axis and a chief paraxial ray, the optical element is a negative lens, and in a case where the optical element is disposed on a reduction side with respect to the intersection point, the optical element is a positive lens. The optical element is configured to satisfy all of the following conditional expressions: 30??d?40 1.225?[nd?(14.387/?d)]?1.276 0.4300?[?gF?(2.9795/?d)]?0.5010, where ?d represents an Abbe number of the optical element, ?gF is a partial dispersion ratio of the optical element for g-line and F-line, and nd is a refractive index of the optical element for d-line.

Abstract: An optical system includes a first lens unit that has a positive refractive power; a second lens unit that is arranged to move during focusing and has a positive or negative refractive power; and a third lens unit that has a positive or negative refractive power. The first lens unit, the second lens unit, and the third lens unit are disposed in that order from an object side to an image side. During the focusing, an interval between adjacent lens units changes. In the optical system, a focal length f of the entire optical system, a distance LD along an optical axis from a lens surface of the first lens unit that is closest to the object side to an image plane, a material of positive lenses included in the first lens unit, and an arrangement of the positive lenses included in the first lens unit are appropriately set.

Abstract: A lens apparatus that includes an optical system including a positive lens, the lens apparatus including a holding member arranged to hold the positive lens, an exterior member arranged to accommodate the holding member, and an engaging mechanism arranged to engage the holding member and the exterior member to each other.

Abstract: An optical system includes a plurality of lenses. The distance from the object side lens surface of a lens arranged an the most object side to the image plane is longer than the focal length of the entire system. The material of a positive lens G1p arranged on the most object side among positive lenses included in the optical system, and the arrangement and material of a negative lens Gn located on the most object side among negative lenses arranged an the image side of the positive lens G1p are appropriately set.

Abstract: An electric vehicle includes drive systems, a control apparatus that controls the drive systems, and wheels. Each drive system includes a motor and an inverter coupled by wires. The wires of the drive systems are coupled by first bypass lines. Each inverter converts direct current power supplied from a corresponding power supply into alternating current power and supplies the alternating current power to the corresponding motor. Each motor drives the corresponding wheel. When an abnormality occurs in the supply of the alternating current power from the inverter to the motor in one drive system, the control apparatus performs control (i) to stop the supply of the alternating current power from the inverter of the one drive systems, and (ii) to supply the alternating current power supplied from the inverter to the motor in another drive system, to the motor of the one drive system via the first bypass lines.

Abstract: An optical system includes a first lens unit that has a positive refractive power; a second lens unit that is arranged to move during focusing and has a positive or negative refractive power; and a third lens unit that has a positive or negative refractive power. The first lens unit, the second lens unit, and the third lens unit are disposed in that order from an object side to an image side. During the focusing, an interval between adjacent lens units changes. In the optical system, a focal length f of the entire optical system, a distance LD along an optical axis from a lens surface of the first lens unit that is closest to the object side to an image plane, a material of positive lenses included in the first lens unit, and an arrangement of the positive lenses included in the first lens unit are appropriately set.

Abstract: An optical system includes a first lens unit that has a positive refractive power; a second lens unit that is arranged to move during focusing and has a positive or negative refractive power; and a third lens unit that has a positive or negative refractive power. The first lens unit, the second lens unit, and the third lens unit are disposed in that order from an object side to an image side. During the focusing, an interval between adjacent lens units changes. In the optical system, a focal length f of the entire optical system, a distance LD along an optical axis from a lens surface of the first lens unit that is closest to the object side to an image plane, a material of positive lenses included in the first lens unit, and an arrangement of the positive lenses included in the first lens unit are appropriately set.

Abstract: In an optical system which includes a positive lens Gp and in which a distance on an optical axis from an object-side lens surface of a lens disposed closest to an object side to an image surface is shorter than a focal length of an entire system, an arrangement and a material of the positive lens Gp, and an arrangement of a focus unit are set appropriately.

Abstract: An optical system includes a negative lens satisfying the following conditional expressions: 30??d?40, 1.225?[nd?(14.387/?d)]?1.276, and 0.4300?[?gF?(2.9795/?d)]?0.5010, where ?d is an Abbe number of the negative lens, ?gF is a partial dispersion ratio of the negative lens at a g-line and an F-line, and nd is a refractive index of the negative lens at a d-line.

Abstract: A conversion lens having a negative refractive power includes a positive lens GP. The positive lens GP satisfies all the following conditional expressions: 30??d?40, 1.225?[nd?(14.387/?d)]?1.276, and 0.4300?[?gF?(2.9795/?d)]?0.5010, where ?d is an Abbe number of the positive lens GP, ?gF is a partial dispersion ratio of the positive lens GP for g-line and F-line, and nd is a refractive index of the positive lens GP for d-line.

Abstract: Provided is a zoom lens, including, in order from an object side to an image side: a first lens unit to a fourth lens unit having negative, positive, negative, and negative refractive powers; and a rear lens group. In the zoom lens, an interval between each pair of adjacent lens units is changed during zooming, the rear lens group has a positive refractive power over an entire zoom range, the third lens unit is configured to move in an optical axis direction during focusing, and each of a focal length of the zoom lens at a wide angle end (fw), and a focal length of the third lens unit (f3) is appropriately set.

Abstract: An optical system is constituted of a first lens unit having a positive refractive power, a second lens unit having a positive refractive power and moving when focusing is performed, and a third lens unit which are arranged in this order from an object side to an image side, and distances between neighboring lens units are changed when focusing is performed. In the optical system, a back focus, arrangement of the second lens unit, and the like are appropriately set.

Abstract: An optical system includes a first lens unit having positive refractive power, a second lens unit, and a third lens unit having negative refractive power arranged in order from an object side to an image side. The second lens unit moves in focusing, thereby changing a distance between adjacent lens units. The first lens unit includes a positive lens, and the third lens unit includes a negative lens. A focal length of the positive lens, a focal length of the negative lens, a focal length of the third lens unit, and a back focus of the optical system are appropriately set.

Abstract: An optical system includes a first lens unit B1 having a positive refractive power, a second lens unit B2, and a third lens unit B3 disposed in order from an object side to an image side. The second lens unit B2 moves in focusing so that an interval between adjacent lens units among the first, second, and third lens units changes. The first lens unit B1 includes a positive lens G1p disposed closest to the object side and a negative lens G1n being a closest negative lens with respect to the object side. The optical system satisfies a predetermined condition.

Abstract: A lens apparatus includes an optical system having a lens, a positive lens, and a negative lens. A material of the positive lens, and a mechanism connecting a holding member holding the positive lens and an exterior member protecting the holding member to each other.

Abstract: An optical system includes an optical element. When the optical element is disposed on a magnification side with respect to an intersection point between an optical axis and a chief paraxial ray, the optical element is a positive lens. When the optical element is disposed on a reduction side with respect to the intersection point, the optical element is a negative lens. The optical element satisfies all of the following conditional expressions: 30??d?40 1.225?[nd?(14.387/?d)]?1.276 0.4300?[?gF?(2.9795/?d)]?0.5010 where ?d is Abbe number of the optical element, ?gF is a partial dispersion ratio of the optical element for g-line and F-line, and nd is a refractive index of the optical element for d-line.