Device and method for performing optical navigation without using lenses

A method for performing optical navigation, the method comprising:

• emitting illumination light from a light source into a target surface to produce imaging light from the target surface;
• transmitting the imaging light from the target surface through an optically transparent flexible film toward a sensor that includes an image sensor array;
• receiving the imaging light from the target surface that is transmitted out of the flexible film at the image sensor array of the sensor to capture frames of image data of the target surface;
• and
• comparing the frames of image data of the target surface to estimate relative displacements between the target surface and the image sensor array.

An optical navigation device comprising:

• a light source configured to emit illumination light;
• a sensor including an image sensor array configured to electronically capture frames of image data of a target surface using imaging light from the target surface, the imaging light from the target surface being produced in response to the illumination light emitted into the target surface, the frames of image data providing displacement information of the target surface relative to the optical navigation device;
• and
• an optically transparent flexible circuit film having an upper surface and a lower surface, the flexible circuit film being positioned relative to the light source and the image sensor array of the sensor such that the illumination light from the light source is transmitted into the target surface through the flexible circuit film and the imaging light from the target surface is transmitted onto the image sensor array of the sensor through the flexible circuit film, the flexible circuit film including conductive traces, at least one of the conductive traces being electrically connected to the sensor.