Patent attributes
An interferometer (10) is provided that has a stage (28) configured to have a linear motion path. A first retroreflector (18) and a second retroreflector (24) are fixedly coupled to the stage (28). A tube (32) is provided, and the stage (28) is configured to reciprocate about the tube (32). A beamsplitter (14) and a 45° mirror (16) are disposed in the tube (32). A detector (22) is configured to detect light passing through the beamsplitter (14), and the beamsplitter (14) is configured to split an incident light beam into a transmitted beam (15) and a reflected beam (17), wherein the transmitted beam (15) passes to the second retroreflector (24) and the reflected beam (17) passes to the first retroreflector (18). The transmitted beam (15) and a reflected beam (17) are focused on the detector (22).