A method of fabricating an X-ray imager including the steps of forming an etch stop layer on a glass substrate and depositing a stack of semiconductor layers on the etch stop layer to form a sensor plane. During use, an actuator erects the cutting head into an operative position and the cover of the housing defines a planar work surface adjacent to the cutting head fixed thereto. Apparatus of the present invention may also be provided with optional stabilization elements for stabilizing vulnerable plaque. The planar waveguide also includes a second layer formed between the first and third layers of a second material having a second index of refraction that is larger than the first index of refraction. A pulse-width modulation duty cycle may be adjusted based on the delta zero crossing error.