Patent ID: 8525975

Claim:
A detector device adapted to be disposed on a mobile robot for detecting a distance between the mobile robot and a surface, said detector device comprising: a detector module including an optical emitter and a photon detector spaced apart from said optical emitter; and a lens module including a lens body disposed adjacent to said detector module, said lens body including: a first light-transmissive surface disposed adjacent to said detector module, said first light-transmissive surface having a first end and a second end opposite to said first end; a second light-transmissive surface extending inclinedly from said first end of said first light-transmissive surface toward said second end of said first light-transmissive surface and away from said detector module; and a third light-transmissive surface extending inclinedly from said second end of said first light-transmissive surface toward said first end of said first light-transmissive surface and away from said detector module; wherein, said optical emitter is operable to emit a light beam passing through said first light-transmissive surface and said second light-transmissive surface toward the surface so as to define a field of emission on the surface, said photon detector being aligned with said first and third light-transmissive surfaces so as to define a field of view on the surface, an extent of overlap between the field of view and the field of emission varying in accordance with a distance between said optical emitter and the surface; and wherein said detector module further includes a detector housing for receiving said optical emitter and said photon detector, said lens module further including a pair of side arms respectively connected to said first and second ends of said first light-transmissive surface, said detector housing having pair of first sides opposite to each other, said side arms respectively abutting against said first sides of said detector housing, one of said side arms being formed with an engaging component for engaging one side of said detector housing opposite to said second and third light-transmissive surfaces of said lens module.