An exposure-suppressing imaging system has a first optical assembly forming a first image of an object on a focal plane thereof, a beam splitter positioned between the first optical assembly and the focal plane of the first optical assembly; an LCOS reflective light modulator positioned on the focal plane, and selectively and partially altering the reflectivity thereof to reflect the first image back to the beam splitter; a second optical assembly positioned on a side of the beam splitter and receiving the reflected first image to form a second image on a focal plane of the second optical assembly; a light sensor converting the second image into a signal; and a controller receiving the signal computed as a third image, and selectively controlling the reflectivity of the LCOS reflective light modulator according to whether the signal contains information of overexposure on the third image.