Device for the interferometric testing of the optical homogeneity of transparent, plate-shaped workpieces

摘要

In a device for the interferometric testing of the optical homogeneity of transparent, plate-shaped workpieces (22), the variation in the optical layer thickness is tested by means of planar recording of an interferogram of the layer thickness interference. The device has a light source (1) for generating a coherent, monochromatic light beam (17) which sequentially scans the workpiece (22). The light beam (26) transmitted through the workpiece and modulated in its intensity passes to a temperature-sensitive paper (27) and causes blackenings there in accordance with the variations in the optical layer thickness. For the purpose of generating a scanning movement between the light beam (17) and the workpiece (22), use is made of a graph plotter (9) on the carriage (8) of which a first deflecting mirror (7) and on the writing head part (15) of which a second deflecting mirror (14) are fixed in such a way that the workpiece (22) is scanned by the scanning light beam (17) in accordance with the movement of the writing head part (15). <IMAGE>