Shape detection on objects of large and huge dimensions has always represented a challenging task, mostly by the practical point of view due to the size of the related measurement equipment. When the tested object is a mirror the measurements is additionally complicated, since the classical techniques of structured light cannot be directly applied. The method proposed in this paper has been applied to measure the curvature of a deformable mirror of 1-meter diameter for a heliostat plant. The mirror shape is obtained studying the spatial variations of a grating projected on the sample and reflected by it on a screen. The measurement set-up employs a PC projector and a digital camera. The results of this curvature assessment are compared to those derived from a simulation obtained by an optical design programme.
Mirror shape detection by Reflection Grating Moiré Method with optical design validation
Fontani D;Francini F;Jafrancesco D;Mercatelli L;Sansoni P
2005
Abstract
Shape detection on objects of large and huge dimensions has always represented a challenging task, mostly by the practical point of view due to the size of the related measurement equipment. When the tested object is a mirror the measurements is additionally complicated, since the classical techniques of structured light cannot be directly applied. The method proposed in this paper has been applied to measure the curvature of a deformable mirror of 1-meter diameter for a heliostat plant. The mirror shape is obtained studying the spatial variations of a grating projected on the sample and reflected by it on a screen. The measurement set-up employs a PC projector and a digital camera. The results of this curvature assessment are compared to those derived from a simulation obtained by an optical design programme.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
