Abstract: Provided is an optical device including an optics including at least two moving groups that are movable along an optical axis and share portions of driving regions; a plurality of actuators configured to move the at least two moving groups along the optical axis, respectively; and a control unit configured to control the positions of the at least two moving groups by operating the actuators, wherein the control unit moves the at least two moving groups independently, such that the position coordinates of the at least two moving groups in one integrated coordinates system do not coincide with each other.

Abstract: A method of controlling zoom of a lighting unit based on brightness of an image may include determining at least one of an angle of view of an optical unit and an optical zoom magnification of the optical unit configured to obtain an image by using an image sensor, determining a zoom adjustment range of a lighting unit based on at least one of the angle of view and the optical zoom magnification, and adjusting zoom of the lighting unit such that brightness of the image meets a preset condition within the zoom adjustment range, wherein a diffusion range of light from the lighting unit is adjusted through the zoom adjustment of the lighting unit.

Abstract: Provided is an optical device including an optics including at least two moving groups that are movable along an optical axis and share portions of driving regions; a plurality of actuators configured to move the at least two moving groups along the optical axis, respectively; and a control unit configured to control the positions of the at least two moving groups by operating the actuators, wherein the control unit moves the at least two moving groups independently, such that the position coordinates of the at least two moving groups in one integrated coordinates system do not coincide with each other.

Abstract: A method of controlling zoom of a lighting unit based on brightness of an image may include determining at least one of an angle of view of an optical unit and an optical zoom magnification of the optical unit configured to obtain an image by using an image sensor, determining a zoom adjustment range of a lighting unit based on at least one of the angle of view and the optical zoom magnification, and adjusting zoom of the lighting unit such that brightness of the image meets a preset condition within the zoom adjustment range, wherein a diffusion range of light from the lighting unit is adjusted through the zoom adjustment of the lighting unit.

Abstract: A zoom lens system that includes a first lens group including at least one lens and having a negative refractive power, and a second lens group including at least one lens and having a positive refractive power in an order from an object side to an image side, wherein the zoom lens system is configured to perform zooming by changing a distance between the first lens group and the second lens group and satisfies: 2<|f1/fw|<2.5 and 0.60<|f1/f2|<0.85, wherein f1 indicates a synthetic focal length of the first lens group, fw indicates an overall focal length at a wide angle end, and f2 indicates a synthetic focal length of the second lens group.

Abstract: A zoom lens system that includes a first lens group including at least one lens and having a negative refractive power, and a second lens group including at least one lens and having a positive refractive power in an order from an object side to an image side, wherein the zoom lens system is configured to perform zooming by changing a distance between the first lens group and the second lens group and satisfies: 2<|f1/fw|<2.5 and 0.60<|f1/f2|<0.85, wherein f1 indicates a synthetic focal length of the first lens group, fw indicates an overall focal length at a wide angle end, and f2 indicates a synthetic focal length of the second lens group.