| 摘要 |
PURPOSE:To display the 2nd band frequency scale when the 2nd band is selected, by providing the 1st band frequency scale on the surface and providing the semitransmitting film on the back side. CONSTITUTION:When the 1st band is selected, an external light L1 is totally reflected on an aluminum vapor-deposited layer 16 and a frequency scale 18 of the 1st band only is observed. When the 2nd band is selected, a lamp 24 is illuminated and a ray L3 transmits through the aluminum vapor-deposited layer 16, a frequency scale 20 of the 2nd band is appeared. A ray L2 is shielded at a light shield film 22 of nontransparent ink, the film 16 corresponding to it loses metallic luster and the 1st scale 18 is disappeared in darkness. |
