The specification discloses a dental curing light including 1) a light engine, 2) a coaxially aligned, camera-based viewing system, and 3) a control system providing a variety of safety features and simplified, operator-friendly operation. The camera's field of view (FOV) is coaxial with the centerline of the curing beam of the light engine. The curing light includes a multi-planar dichroic mirror (MDM) providing viewing and light beam direction aligned with the target. The MDM provide multiple images to the camera from different angles. The camera provides real-time measurement of light intensity reflected back from the targeted surface. Using the multiple image portions reflected by the multi-planar dichroic mirror, the control system computes the distance between the curing light and the target. The reflected intensity and the calculated distance enable the control system to compute a light engine irradiance to achieve a desired irradiance at the targeted surface.
