公开(公告)号：US20230125524A1

公开(公告)日：2023-04-27

申请号：US17974058

申请日：2022-10-26

Applicant: HEXAGON TECHNOLOGY CENTER GMBH

Inventor： Yves SALVADÉ ,  Markus SPRECHER ,  Peter KIPFER ,  Marcel ROHNER ,  Tim MAYER ,  Beat AEBISCHER

IPC: G01D5/30 ,  G01D18/00 ,  B25J19/02

Abstract: An image based opto-electronic encoder for a joint, the encoder having a reading head for the first part of the joint and an optical system, comprising a ball lens for the second part of the joint. The ball lens has a front surface transparent for measuring light and an at least partially reflective, structured back surface. The ball lens has -with respect to the measuring light- a refractive index of at least approximately two or an equal radially varying refractive index, such that a bundle of measuring light rays reflected inside the ball lens from a point of the back surface of the ball lens forms at least approximately a parallel bundle after getting refracted at the front surface of the ball lens. The reading head and the ball lens are rotatable relative to each other in at least two degrees of freedom.