Item checkout device and weigh plate with improved electromagnetic field performance

1. A scale weigh plate for an item checkout device including an electromagnetic field generator and a barcode reader, wherein the scale weigh plate comprises:

a non-metallic planar section made of plastic having a top surface resistant to damage and substantially transparent to electromagnetic fields generated by electronic article surveillance systems and radio frequency identification tag readers;

a section including metal for rigidity and durability, and coplanar with the non-metallic planar section; and

a window coplanar with the non-metallic planar section;

wherein when the weigh plate is installed within the item checkout device, the non-metallic planar section is located over the electromagnetic field generator and the window is located over the barcode reader.

2. The scale weigh plate of claim 1 , wherein the at least one section including metal and coplanar with the non-metallic planar section and the non-metallic planar section are assembled with the window to form the weigh plate in a manner that permits substitution of the non-metallic planar section.

3. A scale weigh plate for an item checkout device including an electromagnetic field generator and a barcode reader, wherein the scale weigh plate comprises:

a first plastic planar section;

a second plastic planar section coplanar with the first plastic planar section;

a window coplanar with and located between the first and second plastic planar sections;

a first metallic planar section located adjacent to and coplanar with first sides of the first and second plastic planar sections and the window; and

a second metallic planar section located adjacent to and coplanar with second sides of the first and second plastic planar sections and the window;

wherein when the weigh plate is installed within the item checkout device, the first and second plastic planar sections are located over the electromagnetic field generator and the window is located over the barcode reader, and the first and second metallic planar sections provide rigidity and durability.

4. The scale weigh plate of claim 3 , wherein the first and second plastic planar sections and the window are along a scan path of the item checkout device.

5. The scale weigh plate of claim 3 , wherein the first metallic planar section is located on an operator side of the item checkout device and the second metallic planar section is located on a side of the item checkout device opposite the operator side.

6. An item checkout device comprising:

a housing;

an electromagnetic field generator in the housing;

a barcode reader in the housing;

a scale assembly in the housing; and

a weigh plate supported by the scale assembly and including a non-metallic planar section made of plastic and located over the electromagnetic field generator and having a top surface resistant to damage and substantially transparent to electromagnetic fields generated by electronic article surveillance systems and radio frequency identification tag readers assembled with a coplanar section including metal for rigidity and durability, and a window coplanar with the non-metallic planar section and located over the barcode reader.

7. The item checkout device of claim 6 , wherein the electromagnetic field generator comprises an electronic article surveillance system.

8. The item checkout device of claim 6 , wherein the electromagnetic field generator comprises a radio frequency identification tag reader.

9. An item checkout device comprising:

a housing;

an electromagnetic field generator in the housing a barcode reader in the housing;

a scale assembly in the housing; and

a weigh plate supported by the scale assembly and including

a first plastic planar section;

a second plastic planar section coplanar with the first non-metallic planar section;

wherein the first and second plastic planar sections are located over the electromagnetic field generator;

a window coplanar with and located between the first and second plastic planar sections and located over the barcode reader;

a first metallic planar section located on an operator side of the item checkout device and adjacent to and coplanar with first sides of the first and second plastic planar sections and the window; and

a second metallic planar section located adjacent to and coplanar with second sides of the first and second plastic planar sections and the window.

10. The item checkout device of claim 9 , wherein the electromagnetic field generator comprises an electronic article surveillance system.

11. The item checkout device of claim 9 , wherein the electromagnetic field generator comprises a radio frequency identification tag reader.

12. The scale weigh plate of claim 1 wherein the non-metallic planar section is a thermoplastic or thermoset plastic.

13. The scale weigh plate of claim 1 wherein the non-metallic planar section is formed by molding thermoset components in liquid form and then curing.

14. The scale weigh plate of claim 1 further comprising a second coplanar section including metal for rigidity and durability and a second coplanar non-metallic section.

15. The scale weigh plate of claim 14 wherein the weigh plate is constructed and assembled in a way that permits substitution of another non-metallic planar section if necessary.

16. The scale weigh plate of claim 1 , wherein the non-metallic planar section further comprises channels for directing spilled liquids.

17. The scale weigh plate of claim 16 , wherein the channels are oriented from a leading side of a checkout device to a trailing side of the checkout device relative to a normal path of items during scanning when the weigh plate is installed within the item checkout device.

18. The scale weigh plate of claim 3 wherein the first and second planar sections are substantially transparent to electromagnetic fields generated by electronic article surveillance systems and radio frequency identification tag readers.

19. The scale weigh plate of claim 9 wherein the first and second planar sections are substantially transparent to electromagnetic fields generated by electronic article surveillance systems and radio frequency identification tag readers.