An optical acoustic panel (100, 150, 904) for absorbing sound and providing a daylight appearance, the optical acoustic panel (100, 150, 904) comprising: - a first side for receiving sound, - a second side for receiving light, the second side being opposite the first side, - a micro perforated foil comprising sub-millimeter holes, the micro perforated foil being light transmitting and being arranged at the first side, the sub-millimeter holes being entrance holes of a cavity, - a spacing structure (108, 500, 550, 600, 630, 660) for spacing the first side at a predefined distance from the second side, wherein the spacing structure (108, 500, 550, 600, 630, 660) comprises a plurality of light transmitting cells (106, 604, 634, 674), the light transmitting cells (106, 604, 634, 674) comprising: - a light transmitting channel for collimating a part of the light received at the second side of the optical acoustic panel (100, 150, 904), wherein the light transmitting channels extend from the first side towards the second side and are filled with air, - a light input window arranged at the second side of the optical acoustic panel (100, 150, 904), - a light exit window, at least a part of the light exit window being arranged at the first side of the optical acoustic panel (100, 150, 904), and - a wall (116, 402) interposed between the light input window and the part of the light exit window, the wall (116, 402) enclosing the light transmitting channel and being characterised in that at least a part of the wall (116, 402) is reflective or transmissive in a predefined spectral range for obtaining a blue light emission at relatively large light emission angles with respect to a normal to the first side of the optical acoustic panel (100, 150, 904). - a first side for receiving sound, - a second side for receiving light, the second side being opposite the first side, - a micro perforated foil comprising sub-millimeter holes, the micro perforated foil being light transmitting and being arranged at the first side, the sub-millimeter holes being entrance holes of a cavity, - a spacing structure (108, 500, 550, 600, 630, 660) for spacing the first side at a predefined distance from the second side, wherein the spacing structure (108, 500, 550, 600, 630, 660) comprises a plurality of light transmitting cells (106, 604, 634, 674), the light transmitting cells (106, 604, 634, 674) comprising: - a light transmitting channel for collimating a part of the light received at the second side of the optical acoustic panel (100, 150, 904), wherein the light transmitting channels extend from the first side towards the second side and are filled with air, - a light input window arranged at the second side of the optical acoustic panel (100, 150, 904), - a light exit window, at least a part of the light exit window being arranged at the first side of the optical acoustic panel (100, 150, 904), and - a wall (116, 402) interposed between the light input window and the part of the light exit window, the wall (116, 402) enclosing the light transmitting channel and being characterised in that at least a part of the wall (116, 402) is reflective or transmissive in a predefined spectral range for obtaining a blue light emission at relatively large light emission angles with respect to a normal to the first side of the optical acoustic panel (100, 150, 904).