A device for sensing suspension operations or biometrics includes a light emitting module and a sensing layer. The light emitting module and the sensing layer are sequentially stacked. The light emitting module includes a plurality of light emitting elements emitting light near the infrared and the sensing layer includes a plurality of quantum dot thin film transistors. The quantum dot thin film transistor includes an active layer and quantum dots covering the active layer. The near-infrared light emitted by the plurality of light emitting elements is reflected by an animate object and received by the quantum dot thin film transistors. The sensing device can better sense suspension operations or biometrics. A method for the procedure is also disclosed.