A light reflecting article is disclosed. The light reflecting article comprises a sample carrying article layered with a light reflecting layer. The light reflecting layer serves for allowing an optical collection and detection system to collect both luminescent light emitted from a sample positioned on the light reflecting article in a direction of the optical collection and detection system, as well as luminescent light emitted from the sample in a direction away from the optical collection and detection system and reflected in the direction of the optical collection and detection system via the light reflecting layer, thereby increasing a sensitivity of luminescent light detection.