A single-molecule detection system and a plurality of methods of detecting a single-molecule object or sequencing a nucleic acid are provided. The single-molecule detection system comprises: a movable light coupler (100), a waveguide (110) and a light detector (102). The waveguide (110) comprises: a core layer (112) and a first cladding layer (114), wherein at least one adapter site (104) for the movable light coupler (100) is formed in at least the first cladding layer (114). In the methods, the detection system is used to detect a single-molecule object or sequence a nucleic acid.
