ASTM C1652 – Standard Test Method for Measuring Optical Distortion in Flat Glass Products Using Digital Photography of Grids
Description:
Significance and Use
5.1 This test method provides accurate data for evaluation of the optical properties of the glass being inspected.
5.2 The procedure described is useful for observing the roll wave introduced during the tempering process of flat architectural glass. (1)
5.3 This test method is also useful for inspection of laminated and tempered automotive glass in transmitted light, in both flat and curved geometries.
Scope
1.1 This test method covers the determination of optical distortion of heat-strengthened and fully tempered architectural glass substrates which have been processed in a heat controlled continuous or oscillating conveyance oven. See Specifications C1036 and C1048 for discussion of the characteristics of glass so processed. In this test method the reflected image of processed glass is photographed and the photographic image analyzed to quantify the distortion due to surface waviness. The test method is also useful to quantify optical distortion observed in transmitted light in laminated glass assemblies.
1.2 The values stated in either SI units or inch-pound units are regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.
1.3 There is no known ISO equivalent to this test method.
ASTM C1651