An eyewear comprising: an optical module whose optical characteristics change; an input section configured to receive an instruction from a user; a sensor section configured to detect a use condition of the optical module; a storage section configured to store at least a condition of changing the optical characteristics of the optical module; and a control section configured to change the optical characteristics of the optical module by an electric control in accordance with a setting mode, wherein the setting mode includes at least a first mode in which the control section performs the electric control on the optical module on a basis of the condition stored in the storage section and a detection value of the sensor section, and a second mode in which the control section performs the electric control on the optical module on a basis of the instruction received by the input section, characterized in that the optical characteristics include a refractive index of the optical module and a transmittance of the optical module with respect to visible light, and the condition stored in the storage section is updated on a basis of a detection value of the sensor section that is obtained at a time when the input section receives an instruction in the second mode. an optical module whose optical characteristics change; an input section configured to receive an instruction from a user; a sensor section configured to detect a use condition of the optical module; a storage section configured to store at least a condition of changing the optical characteristics of the optical module; and a control section configured to change the optical characteristics of the optical module by an electric control in accordance with a setting mode, wherein the setting mode includes at least a first mode in which the control section performs the electric control on the optical module on a basis of the condition stored in the storage section and a detection value of the sensor section, and a second mode in which the control section performs the electric control on the optical module on a basis of the instruction received by the input section, a first mode in which the control section performs the electric control on the optical module on a basis of the condition stored in the storage section and a detection value of the sensor section, and a second mode in which the control section performs the electric control on the optical module on a basis of the instruction received by the input section, characterized in that the optical characteristics include a refractive index of the optical module and a transmittance of the optical module with respect to visible light, and the condition stored in the storage section is updated on a basis of a detection value of the sensor section that is obtained at a time when the input section receives an instruction in the second mode. the optical characteristics include a refractive index of the optical module and a transmittance of the optical module with respect to visible light, and the condition stored in the storage section is updated on a basis of a detection value of the sensor section that is obtained at a time when the input section receives an instruction in the second mode.