| 摘要 |
PROBLEM TO BE SOLVED: To provide an observation window having an operation hole, which will not cloud or frost, when being attached to a portion directly near the operation hole and which is realized, by improving conventional one employed in an environmental testing apparatus or the like. SOLUTION: Operation holes 15, 16 are formed in a transparent substrate 6, and a conductive heating layer 20 is disposed on the whole region except the operation holes, and bus lines (main electrodes) 21, 22 are disposed on the right and the left sides of the transparent substrate 6, and auxiliary electrodes 25, 26 are disposed near the operation holes 15, 16. The auxiliary electrodes 25, 26 are constituted of one side auxiliary electrode strip 27 and other side auxiliary electrode strip 28. The one and the other side auxiliary electrode strips 27, 28 are configured symmetric and are both of circular arc shape. The auxiliary electrode strips 27, 28 are arranged concentric with the operation holes 15, 16. COPYRIGHT: (C)2006,JPO&NCIPI |
