An improved cat's-eye retroreflector used in a laser tracking interferometer system

As an optical retroreflector used in a laser interferometer system, a cat's eye is expected to provide high parallelism of the reflected beam, especially for large-range measurements. On the other hand, a cat's eye should be light and portable for the convenience of operation in taking the actual measurement. To solve these problems, a new method for optimizing the parameters of a cat's eye is proposed to obtain the least divergence angle of the reflected beam. Theoretical analysis and experiment show that the improved cat's eye not only has smaller volume and less weight, but also greatly improves the parallelism of the reflected beam.