A system and method for performing optical navigation uses scattered light to produce frames of image data to estimate displacement with respect to a target surface. The scattered light is produced from an illumination beam of light emitted along a first optical axis onto the target surface. The illumination...http://www.google.co.uk/patents/US8138488?utm_source=gb-gplus-sharePatent US8138488 - System and method for performing optical navigation using scattered light
