Radio frequency screen for an ultraviolet lamp system

Patent metadata

Field	Value
Publication number	US-11670491-B2
Application number	US-202016929881-A
Country	US
Kind code	B2
Filing date	Jul 15, 2020
Priority date	Jul 15, 2020
Publication date	Jun 6, 2023
Grant date	Jun 6, 2023

Abstract

A radio frequency (RF) screen for a microwave powered ultraviolet (UV) lamp system is disclosed. In one example, a disclosed RF screen includes: a sheet comprising a conductive material; and a frame around edges of the sheet. The conductive material defines a predetermined mesh pattern of individual openings across substantially an operative area of the screen. Each of the individual openings has a triangular shape.

First claim

What is claimed is:

1. A radio frequency (RF) screen, comprising:
a sheet comprising a conductive material; and
a frame around edges of the sheet,
wherein the conductive material defines a predetermined mesh pattern of individual openings across substantially an operative area of the screen,
wherein each of the individual openings has a triangular shape, and
wherein the predetermined mesh pattern comprises 16 to 36 individual openings per unit area of 1 square centimeter.

2. The RF screen of claim 1 , wherein:
each of the individual openings is in a shape of an isosceles triangle.

3. The RF screen of claim 2 , wherein:
the predetermined mesh pattern tiles a surface of the sheet with periodic parallelograms each of which is formed by a plurality of isosceles triangles.

4. The RF screen of claim 1 , wherein:
each of the individual openings is in a shape of an equilateral triangle.

5. The RF screen of claim 1 , wherein:
each of the individual openings is in a shape of a right triangle.

6. The RF screen of claim 5 , wherein:
the predetermined mesh pattern tiles a surface of the sheet with periodic rectangles each of which is formed by a quantity of right triangles.

7. The RF screen of claim 6 , wherein:
the quantity is: 2, 4 or 8.

8. The RF screen of claim 1 , wherein:
the predetermined mesh pattern comprises a plurality of rows each of which is formed by periodic cells comprising at least one triangle; and
the periodic cells in at least two adjacent rows are not aligned to each other.

9. The RF screen of claim 1 , wherein:
the individual openings have shapes of multiple types of triangles; and
the multiple types of triangles comprise at least one of: an isosceles triangle, a right triangle, an equilateral triangle, or a scalene triangle.

10. The RF screen of claim 1 , wherein:
the sheet has a thickness between 0.001 inch and 0.015 inch.

11. A microwave powered ultraviolet (UV) lamp system, comprising:
at least one magnetron configured to convert electrical power received from a power supply to radio frequency (RF) energy;
a UV bulb configured to be excited by the RF energy to emit UV light; and
an RF screen, wherein the RF screen comprises:
a sheet comprising a conductive material,
wherein the conductive material defines a predetermined mesh pattern of individual openings across,

wherein at least one of the individual openings has a triangular shape, and
wherein the predetermined mesh pattern comprises 16 to 36 individual openings per unit area of 1 square centimeter.

12. The microwave powered UV lamp system of claim 11 , wherein:
at least one of the individual openings has a rectangular shape.

13. The microwave powered UV lamp system of claim 11 , wherein:
the sheet has a rectangular surface with four edges; and
the predetermined mesh pattern tiles the rectangular surface of the sheet with a plurality of triangles in proximity of the four edges and a plurality of rectangles surrounded by the plurality of triangles.

14. The microwave powered UV lamp system of claim 11 , wherein:
the RF screen is configured to yield an increase in UV light transmittance compared to a reference screen with a mesh pattern comprising individual openings each of which is in a shape of: a square, a rectangle, or a hexagon; and
the RF screen and the reference screen have a same number of individual openings in a unit area.

15. The microwave powered UV lamp system of claim 11 , wherein:
the RF screen is configured to yield a decrease in maximum deformation compared to a reference screen with a mesh pattern comprising individual openings each of which is in a shape of: a square, a rectangle, or a hexagon; and
the RF screen and the reference screen have a same number of individual openings in a unit area.

16. The microwave powered UV lamp system of claim 11 , wherein:
the RF screen is configured to yield a decrease in maximum stress compared to a reference screen with a mesh pattern comprising individual openings each of which is in a shape of: a square, a rectangle, or a hexagon; and
the RF screen and the reference screen have a same number of individual openings in a unit area.

17. The microwave powered UV lamp system of claim 11 , wherein:
the conductive material comprises copper, brass, stainless steel, tungsten, aluminum, nickel, silver, or combinations thereof.

18. A method, comprising:
converting an input electrical power to radio frequency (RF) energy;
exciting a ultraviolet (UV) bulb with the RF energy to emit a UV light; and
screening the RF energy with an RF screen comprising a sheet having a predetermined mesh pattern of individual openings, wherein at least one of the individual openings has a triangular shape, and
wherein the predetermined mesh pattern comprises 16 to 36 individual openings per unit area of 1 square centimeter.

19. The method of claim 18 , further comprising:
passing the UV light through the RF screen with a light transmittance greater than 70%.

20. The method of claim 18 , wherein:
passing the UV light through the RF screen with a light transmittance greater than 75%.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Yang Sheng-Chun
• Liang Po-Wei
• Wan Chao-Hung
• Lin Yi-Ming
• Kang Liu Che

Classifications

• H01J65/044

  the field being produced by a separate microwave unit · CPC title

• H01J2237/0266

  electromagnetic · CPC title

• H05B3/0033 Primary

  Heating devices using lamps · CPC title

• H01J37/32651 Primary

  Shields, e.g. dark space shields, Faraday shields · CPC title

• H01J61/103 Primary

  Shields, screens or guides arranged to extend the discharge path (H01J61/106 takes precedence) · CPC title