Abstract: A toothbrush head for an electric toothbrush including a driving shaft, includes a brush rod and a connecting member. The brush rod has a first end configured to carry bristles and a second end configured to be connected with the driving shaft, the second end defines a holding groove, and a lower surface of the second end is provided with an opening communicated with the holding groove. The connecting member includes a connecting body and an elastic piece connected to the connecting body. The connecting body is arranged inside the holding groove, the elastic piece is arranged between the opening and the connecting body and resists against an inner sidewall surrounding the holding groove. The opening and the holding groove are configured to allow the driving shaft to be inserted therethrough to be engaged with the connecting body.

Abstract: The disclosure provides a collimator assembly, comprising at least at least two collimators configured to be moveable relative to each other such that the collimator assembly is switchable between at least two collimation modes; in respective collimation modes, the at least two collimators are superposed with each other in a thickness direction of the collimator assembly, such that the collimator assembly presents different combined patterns for collimating and shielding rays incident onto the collimator assembly and that the collimator assembly has corresponding ray shielding thickness for effectively shielding rays.

Abstract: The disclosure provides a collimator assembly, comprising at least at least two collimators configured to be moveable relative to each other such that the collimator assembly is switchable between at least two collimation modes; in respective collimation modes, the at least two collimators are superposed with each other in a thickness direction of the collimator assembly, such that the collimator assembly presents different combined patterns for collimating and shielding rays incident onto the collimator assembly and that the collimator assembly has corresponding ray shielding thickness for effectively shielding rays.