摘要 |
A phase shifting interferometer (1) includes a light source (2), a reference optical path (5), a measurement optical path (4), which includes a mounting device (32) to support an optical element (37) to be tested, and a light splitter (3). The light splitter (3) splits light (18) from the light source (2) to the reference optical path (5) and to the measurement optical path (4) and to recombine light from the reference optical path (5) and the measurement optical path (4) and directs the recombined light (27) to a detector. The light source includes a GaAs-AlGaAs distributed Bragg reflector wavelength tunable laser diode (10). |