| 摘要 |
PURPOSE:To improve the yield of products by forming opaque ring-like patterns having size capable of surrounding holes punched on a sheet. CONSTITUTION:When the jig 30 is set up, a ring-like pattern 32 surrounds a buyer hole 2. In the case of C, light 40 from a light source 21 is interrupted by a green sheet 3, light 41 reflected by the sheet 3 is reached to eyes 22 and a black ring-like pattern 33 can be observed so as to be floated from the whitish surface of the sheet 3. In the case of B, light is passed through an unspecified hole 23 and a film, diffracted as transmitted and diffracted light 42 through the hole 23, reached to the eyes 22 without being interrupted, and observed as a bright hole at larger area 43 than the hole 23. In the case of A, light is transmitted through a hole 2 and the film as transmitted and diffracted light 44 and reflected and diffracted light 45 and diffracted as a ring-like pattern 32, an area 46 smaller than the B is brightened and a part of the area 46 can be observed so as to be floated. The pattern 33 observed as a floated pattern is an unpunched position and the large bright pattern can be decided as an unspecified hole. Consequently, the yield of ceramic sheathed wiring boards is improved. |
