NOVELTY - A photovoltaic device comprises a transparent electrode (10); a metal electrode (16); and several photovoltaic layers (14) between the electrodes. The photovoltaic layers comprise light-absorbing compounds for absorbing different light absorption wavelength bands. Each of the photovoltaic layers comprises an electron accepting material.    USE - As a photovoltaic device comprising solar cell and organic optical sensor (claimed).    ADVANTAGE - The photovoltaic device includes several photovoltaic layers having different light absorption regions and can thereby have a relatively high photoelectric efficiency.    DETAILED DESCRIPTION - A photovoltaic device comprises a transparent electrode (10); a metal electrode (16); and several photovoltaic layers (14) between the electrodes. The photovoltaic layers comprise light-absorbing compounds for absorbing different light absorption wavelength bands. Each of the photovoltaic layers comprises an electron accepting material. The photovoltaic layers comprise a first photovoltaic layer containing a short-wavelength absorption compound on the transparent electrode; and a second photovoltaic layer containing a long-wavelength absorption compound on the metal electrode. In the device, a thickness ratio between the first photovoltaic layer and the second photovoltaic layer is 1:1-1:3. The first photovoltaic layer has a thickness of 30-150 nm. The short-wavelength absorption compound is for absorbing light having a wavelength of 400-600 nm. The short-wavelength absorption compound is present in an amount of 20-400 parts by weight (pbw) based on 100 pbw of the electron accepting material. The second photovoltaic layer has a thickness of 30-200 nm. The long-wavelength absorption compound has a wavelength of 400-900 nm. The long-wavelength absorption compound is present in an amount of 20-400 pbw based on 100 pbw of the electron accepting material. The device further comprises a buffer layer between the transparent electrode and photovoltaic layer, or between the photovoltaic layer and the metal electrode; an inter-electrode between the photovoltaic layers; and an electron injection layer (18) between the metal electrode and the photovoltaic layers. The buffer layer comprises a material with a working voltage of less than or equal to 5.2 eV. The inter-electrode comprises a material with a working voltage of less than or equal to 5.2 eV. An INDEPENDENT CLAIM is included for a method of manufacturing a photovoltaic device, involving forming a transparent electrode on a transparent substrate; forming a first photovoltaic layer comprising a short-wavelength absorption compound and an electron accepting material on the transparent electrode; forming a second photovoltaic layer comprising a long-wavelength absorption compound and an electron accepting material on the first photovoltaic layer; and forming a metal electrode on the second photovoltaic layer.    DESCRIPTION OF DRAWING(S) - The figure shows a partial cross-sectional view of the photovoltaic device.    Substrate (10)    Transparent electrode (12)    Photovoltaic layers (14)    Metal electrode (16)    Electron injection layer (18)