The invention relates to a receptacle (4) for receiving a sample (5) during an optical analysis of the sample (5), wherein the receptacle (4) comprises a bottom (19) which is at least partially transparent so that the sample (5) within the receptacle (4) can be optically analyzed by an image sensor (6) from below the bottom (19) and wherein the bottom (19) is very thin thereby improving contrast and sharpness of the images generated by the image sensor (6). Further, the invention relates to a system for optically analyzing a sample (5).