Design and implementation of a CMOS Modulated Light Camera

Modulated Light Cameras represent a breed of cameras designed specifically to capture intensity modulated light. This is because using coherent detection it is possible to lift a signal of interest out of the background noise and thus increase the precision of measurements. This work presents a camera designed to detect the phase of amplitude modulated light. By implementing an in-pixel demodulation, wide-field detection of the phase of light is possible. The camera provides 32 by 32 pixels, each with a pitch of 115 μm with a fill factor of 16 %. This pixel used in the camera introduces a novel tuning mechanism that matches the camera to the frequency of operation and light conditions. This enables the camera to work at high modulation depths, and increases the detection frequency to 50 MHz. The camera also provides an improved linear response without compromising on dynamic range and pixel size. The noise response of the camera is also improved as compared with previous work performed. The camera has been demonstrated in wide-field range measurements of a scene (Imaging LIDAR). It has also been applied to wide-field heterodyne interforemetry and in ultra-stable interferometry