Wiring structure using flexible printed circuit board and optical module using the same

• US 20070054517A1
• Filed: 09/07/2005
• Published: 03/08/2007
• Est. Priority Date: 09/07/2005
• Status: Active Grant

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Hidaka, Hirotoshi
• Granted Patent: US 7,234,965 B2
• Time in Patent Office: Days
• US Class Current: 439/79
• CPC Class Codes: H05K 1/0281 Reinforcement details thereof
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/096 Vertically aligned vias, holes or stacked vias
• CPC Class Codes: H05K 2201/10121 Optical component, e.g. opto-electronic component
• CPC Class Codes: H05K 2201/2009 Reinforced areas, e.g. for a specific part of a flexible printed circuit
• CPC Class Codes: H05K 3/0058 Laminating printed circuit boards onto other substrates, e.g. metallic substrates H05K1/0281 takes precedence
• CPC Class Codes: H05K 3/3447 Lead-in-hole components H05K3/3415 takes precedence

Abstract

The present invention prevents the wiring pattern formed on the FPC board with the support board from being damaged or broken by the edge of the support board when the FPC board is bend at the edge portion of the supper board. According to the invention, the FPC board, providing the wiring pattern at least one surface thereof, is stuck with the support board on the surface the wiring pattern is formed. The support board of the invention has a clipped portion in the edge, along which the FPC board is bent, corresponding to a region where the wiring pattern passes.

Claims

1. A wiring structure, comprising:

a flexible printed circuit board having a first region and a second region, at least one surface of said flexible printed circuit board forming a wiring pattern extending from said first region to said second region, said flexible printed circuit board being bent with a preset radius at a boundary between said first and second regions as said wiring pattern being inward; and

a support board stuck with said one surface of said first region of said flexible printed circuit board to support said flexible printed circuit board, said support board having a region clipped from said boundary, said clipped region having a width at least three times wider than a width of said wiring pattern passing said clipped region,

wherein a gap between an edge of said wiring pattern and an edge of said clipped region is substantially equal to said width of said wiring pattern.

2. The wiring structure according to claim 1,

wherein said preset radius is smaller than 2 millimeters.

4. The wiring structure according to claim 1,

wherein

said gap is substantially equal in both sides of said wiring pattern.

5. The wiring structure according to claim 1,

wherein said support board is made of polyimide.

3. (canceled)

6. An optical subassembly having a plurality of lead pins connected with an electronic circuit, said optical subassembly comprising:

a wiring structure, for connecting said plurality of lead pins to said electronic circuit, including

a flexible printed circuit board having a first region and a second region, at least one surface of said flexible printed circuit board forming a wiring pattern extending from said first region to said second region, said flexible printed circuit board being bent with a preset radius at a boundary between said first and second regions as said wiring pattern being inward, said flexible printed circuit board having a plurality of via-holes to pass said plurality of lead pins, said via-holes having a lands to surround said via-holes and to be soldered with said lead pins, and

a support board attached to said one surface of said first region of said flexible printed circuit board to support said flexible printed circuit board, said support board having a plurality of via-holes aligned with said via-holes in said flexible printed circuit board to pass said plurality of said lead pins,

wherein said support board has a region clipped from said boundary, said wiring pattern passing said clipped region.

7. The optical subassembly according to claim 6,

wherein said preset radius is smaller than 2 millimeters.

8. The optical subassembly according to claim 6,

wherein a width of said clipped region is at least three times wider than a width of said wiring pattern, and

a gap from an edge of said wiring pattern to an edge of said clipped region is substantially equal to said width of said wiring pattern.

9. The wiring structure according to claim 6,

wherein said support board is made of polyimide.

10. A wiring structure, comprising:

a flexible printed circuit board including first and second regions and having a first surface and a second surface opposite to said first surface, said first surface forming a wiring pattern extending from said first region to said second region, said wiring pattern having a bend with a preset radius at a boundary between said first and second regions with said first surface located inside of said bend; and

a support board stuck with said first surface of said first region of said flexible printed circuit board to support said flexible printed circuit board, said support board having a clipped region, said bend in said wiring pattern passing within said clipped region and not passing in regions outside of said clipped region, said clipped region having a width wider than a width of said bend in said wiring pattern.

11. The optical subassembly according to claim 10,

wherein said preset radius is smaller than 2 millimeters.

12. The optical subassembly according to claim 10,

wherein a width of said clipped region is at least three times wider than a width of said wiring pattern, and

a gap from an edge of said wiring pattern to an edge of said clipped region is substantially equal to said width of said wiring pattern.

13. The wiring structure according to claim 10,

wherein said support board is made of polyimide.