An optical navigation device detects relative motion of non-optically flat surfaces, e.g. fingers by comparing the captured images of the surface texture, e.g. ridges on the finger. Within a housing, a light source and a sensor array are positioned proximately. The sensor array is mounted on a substrate. A lens array interposes the surface to be imaged and the sensor array such that a 1:1 image of the surface, e.g. finger surface of the user onto the 2D sensor array, is formed. The micro-lenses may be designed to match individual pixels on the sensor array, or each element of the lens array is used to cover a group of pixels on the sensor. The micro-lenses may be positioned such that the image is formed onto the sensor array or formed in a plane in space such that the image is defocused from the surface.