A time of flight, TOF, assembly, comprising: a laser light source that emits an infrared laser pulse; an emission housing provided with a receiving cavity, wherein the laser light source and an optical element are arranged in the receiving cavity, wherein the optical element is arranged on a light path of the infrared laser, and the infrared laser emitted by the laser light source is transmitted through the optical element and then enters an external environment, a plurality of photo detectors, configured to receive light and convert the received light into an electric signal; and a detection circuit, configured to send a turning-off control signal to turn off the laser light source, in response to the electric signal indicating that a time length, in which the laser light source is in an effective working state within a first duration, is greater than a preset time length threshold value, or the electric signal indicating that energy of light emitted from the laser light source within a second duration is greater than a preset energy threshold value, wherein the electric signal having an amplitude greater than a first preset amplitude threshold value indicates that the laser light source is in the effective working state, characterized in that, at least one of the plurality of photo detectors is arranged outside the receiving cavity and mainly receives light in the external environment to generate a first electric signal before the laser light source is turned on, and at least another one of the plurality of photo detectors is arranged in the receiving cavity and mainly receives infrared laser reflected by the optical element or an inner wall of the emission housing and the light in the external environment to generate a second electric signal after the laser light source is turned on, and wherein the first electric signal and the second electric signal are processed to acquire the electric signal, wherein when the first electric signal and the second electric signal are processed, an amplitude of the first electric signal is subtracted from an amplitude of the second electric signal to acquire the electric signal. a laser light source that emits an infrared laser pulse; an emission housing provided with a receiving cavity, wherein the laser light source and an optical element are arranged in the receiving cavity, wherein the optical element is arranged on a light path of the infrared laser, and the infrared laser emitted by the laser light source is transmitted through the optical element and then enters an external environment, a plurality of photo detectors, configured to receive light and convert the received light into an electric signal; and a detection circuit, configured to send a turning-off control signal to turn off the laser light source, in response to the electric signal indicating that a time length, in which the laser light source is in an effective working state within a first duration, is greater than a preset time length threshold value, or the electric signal indicating that energy of light emitted from the laser light source within a second duration is greater than a preset energy threshold value, wherein the electric signal having an amplitude greater than a first preset amplitude threshold value indicates that the laser light source is in the effective working state, characterized in that, at least one of the plurality of photo detectors is arranged outside the receiving cavity and mainly receives light in the external environment to generate a first electric signal before the laser light source is turned on, and at least another one of the plurality of photo detectors is arranged in the receiving cavity and mainly receives infrared laser reflected by the optical element or an inner wall of the emission housing and the light in the external environment to generate a second electric signal after the laser light source is turned on, and wherein the first electric signal and the second electric signal are processed to acquire the electric signal, wherein when the first electric signal and the second electric signal are processed, an amplitude of the first electric signal is subtracted from an amplitude of the second electric signal to acquire the electric signal.