Provided is a spectral filter including a first Bragg reflective layer, a second Bragg reflective layer that is spaced apart from the first Bragg reflective layer and includes a cavity, the first resonance layer being provided between the first Bragg reflective layer and the second Bragg reflective layer, a second resonance layer including at least a portion of the first Bragg reflective layer, the second Bragg reflective layer, and the cavity, a third Bragg reflective layer, a fourth Bragg reflective layer spaced apart from the third Bragg reflective layer, wherein the second resonance layer is provided between the third Bragg reflective layer and the fourth Bragg reflective layer.