| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a deterioration determining device for determining the degree of deterioration of an impurity removing member such as a chemical filter before an optical part or the like is exposed to impurities. <P>SOLUTION: The deterioration determining device includes a light guide part (half mirror 11) for guiding the light from a light source (short wavelength light source 28), a deterioration determining member (target plate 12) exposed to the impurities in an atmosphere other than a desired atmosphere under irradiation with the light guided from the light guide part, and a monitor part (a photoelectric sensor 14 and a monitor part 16) for monitoring the degree of deterioration of the deterioration determining member. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
