Abstract
A surface shape measurement of a polyimide film was performed by using the Grating Projection Method (GPM) in order to discuss applicability of the GPM for measuring the surface shape of the permeable and highly reflective thin membranes of space structures. The measurement results showed that the GPM can measure the permeable and highly reflective flat polyimide film with the same measurement accuracy of the mat metal plate except for the specularly-reflected area of the polyimide film. It was shown that the optical property of the polyimide film such as the diffuse reflector and permeability did not affect the measurement accuracy, while measurement variations were affected. In addition, through the measurement of the polyimide film with wrinkles and slacks, the GPM can successfully capture the local wrinkles and slacks of the polyimide films in the diffuse reflector area. From the results, an applicability of the method to measure the surface shape of the polyimide film was shown.