We present an imaging sensor used in the viscoelastic detection of composite resins. Composite resins are the mainstream materials in dental restorative procedures. After restoring the carious cavity, the module of the composite resin increases with the curing time of the light-curing unit. After a specific time, the composite resin is cured to the ideal state (not completely cured; this refers to the initial curing of the dental restorative material, after which it takes some time to cure completely). The sensor provides a new, fast, and non-contact optical method for module detection of composite resins. This study determined the time required to cure composite resins ideally by qualitative analysis of decorrelation time (τ) and quantitative module G*(w). The results showed that the composite resin cured ideally in the ninth second and exhibited a high linear correlation (r = 0.965, p = 0.007 81). The successful development of this sensor will help to avoid subjective judgment about the curing degree of composite resins and detect the curing process of composite resins.
