Study on Automatic Test Technique for Optical Athermal Focusing Curve

In the athermal design of the optical system, the collection of the temperature compensated focusing curve is the most time-consuming, laborious, and prone to deviation. In this paper, an automatic test techinique for optical athermal focusing curve is proposed, which is to collect the picture imaged of four-bar target at a certain temperature acquired by a imaging system, automatically confirm the image resolution through image algorithm, record the focal length in the clearest state, and finally automatically fit the temperature compensated focusing curve after all focal length within the operation temperature are gone through. Experiments show that this method can automatically collect and fit the temperature compensated focusing curve, which saves time, labor and enhances accuracy.