Patent attributes
An optical acoustic panel 100 for absorbing sound and providing a daylight appearance and a luminaire are provided. The optical acoustic panel 100 comprises a first side 114, a second side 104, a micro perforated foil 110 and a spacing structure 108. The first side 114 receives sound. The second side 104 is opposite the first side 114 and receives light. The micro perforated foil 110 comprises sub-millimeter holes 112, is light transmitting and is arranged at the first side 114. The sub-millimeter holes 112 are entrance holes of a cavity. The spacing structure 108 spaces the first side 114 at a predefined distance from the second side 104. The spacing structure 108 comprises a plurality of light transmitting cells 106. The light transmitting cells 106 comprise a light transmitting channel 118, a light exit window 122, a light input window 120 and a wall 116. The light transmitting channel 118 collimates a part of the light received at the second side 104 of the optical acoustic panel 100. The light transmitting channels 118 extend from the first side 114 towards the second side 104 and are filled with air. The light input window 120 is arranged at the second side 104. At least a part of the light exit window 122 being arranged at the first side 114. The wall 116 is interposed between the light input window 120 and the part of the light exit window 122. The wall 116 encloses the light transmitting channel 118. At least a part of the wall 116 being 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 114.