A sensor, comprising: a visible light sensor configured to sense light in a visible wavelength spectrum; a near infra-red light sensor stacked on the visible light sensor, the near infra-red light sensor being configured to sense light in a near infra-red wavelength spectrum; and an optical filter on the near infra-red light sensor, the optical filter configured to selectively transmit the light in the visible wavelength spectrum and the light in the near infra-red wavelength spectrum, wherein the optical filter is configured to: selectively transmit light in a first wavelength spectrum associated with the visible wavelength spectrum and light in a second wavelength spectrum associated with the near infra-red wavelength spectrum; and selectively block light in a third wavelength spectrum between the first wavelength spectrum and the second wavelength spectrum, wherein a transmission spectrum of the optical filter has a near infra-red transmission peak in the second wavelength spectrum, and a wavelength range of the near infra-red transmission peak at a 50% transmittance of the transmission spectrum of the optical filter is less than or equal to 120 nm, and characterized in that the near infra-red transmission peak satisfies Relationship Equations 1 and 2: λ 2 − λ 1 ≤ 50 nm λ 4 − λ 3 ≤ 50 nm wherein, in Relationship Equations 1 and 2, λ 1 is a starting point wavelength in the near infra-red transmission peak, λ 2 is a starting point wavelength at which transmittance of the optical filter is greater than or equal to 50 % in the near infra-red transmission peak, λ 3 is an end-point wavelength at which the transmittance of the optical filter is greater than or equal to 50 % in the near infra-red transmission peak, and λ 4 is an end-point wavelength of the near infra-red transmission peak. a visible light sensor configured to sense light in a visible wavelength spectrum; a near infra-red light sensor stacked on the visible light sensor, the near infra-red light sensor being configured to sense light in a near infra-red wavelength spectrum; and an optical filter on the near infra-red light sensor, the optical filter configured to selectively transmit the light in the visible wavelength spectrum and the light in the near infra-red wavelength spectrum, wherein the optical filter is configured to: selectively transmit light in a first wavelength spectrum associated with the visible wavelength spectrum and light in a second wavelength spectrum associated with the near infra-red wavelength spectrum; and selectively block light in a third wavelength spectrum between the first wavelength spectrum and the second wavelength spectrum, wherein a transmission spectrum of the optical filter has a near infra-red transmission peak in the second wavelength spectrum, and a wavelength range of the near infra-red transmission peak at a 50% transmittance of the transmission spectrum of the optical filter is less than or equal to 120 nm, and characterized in that the near infra-red transmission peak satisfies Relationship Equations 1 and 2: λ 2 − λ 1 ≤ 50 nm λ 4 − λ 3 ≤ 50 nm wherein, in Relationship Equations 1 and 2, λ 1 is a starting point wavelength in the near infra-red transmission peak, λ 2 is a starting point wavelength at which transmittance of the optical filter is greater than or equal to 50 % in the near infra-red transmission peak, λ 3 is an end-point wavelength at which the transmittance of the optical filter is greater than or equal to 50 % in the near infra-red transmission peak, and λ 4 is an end-point wavelength of the near infra-red transmission peak. selectively transmit light in a first wavelength spectrum associated with the visible wavelength spectrum and light in a second wavelength spectrum associated with the near infra-red wavelength spectrum; and selectively block light in a third wavelength spectrum between the first wavelength spectrum and the second wavelength spectrum, wherein a transmission spectrum of the optical filter has a near infra-red transmission peak in the second wavelength spectrum, and a wavelength range of the near infra-red transmission peak at a 50% transmittance of the transmission spectrum of the optical filter is less than or equal to 120 nm, and characterized in that the near infra-red transmission peak satisfies Relationship Equations 1 and 2: λ 2 − λ 1 ≤ 50 nm λ 4 − λ 3 ≤ 50 nm wherein, in Relationship Equations 1 and 2, λ 1 is a starting point wavelength in the near infra-red transmission peak, λ 2 is a starting point wavelength at which transmittance of the optical filter is greater than or equal to 50 % in the near infra-red transmission peak, λ 3 is an end-point wavelength at which the transmittance of the optical filter is greater than or equal to 50 % in the near infra-red transmission peak, and λ 4 is an end-point wavelength of the near infra-red transmission peak.