A new method to characterize degradation of first surface aluminum reflectors

This paper reports the development of a new optical instrument capable of characterizing the aging process of enhanced first surface aluminum reflectors for concentrating solar power (CSP) application. The device measures the specular reflectance at three acceptance angles and the wavelengths with spatial resolution using a digital camera's CMOS sensor. It can be used to measure the corrosion growth rate during outdoor and accelerated exposure tests. These results will allow a correlation between the degraded mirror surface and its specular reflectance.