US Patent 10515252 Optical element fabrication method and optical sensing device

An optical element fabrication method including following steps are provided. First, a micro-lens layer including a micro-lens and a first substrate is provided. Besides, a micro optical channel layer including a micro optical channel and a second substrate is provided. A first bonding process is performed to bond the micro-lens layer to the micro optical channel layer, wherein the micro-lens is corresponded to the micro optical channel in a direction that is perpendicular to the surface of the second substrate, and the first substrate of the micro-lens layer is removed later.