Electromagnetic wave filter for plasma display panel

• US 6,316,110 B1
• Filed: 03/10/1999
• Issued: 11/13/2001
• Est. Priority Date: 04/16/1998
• Status: Expired due to Fees

• Current Assignee: Nippon Sheet Glass Company Limited
• Original Assignee: Nippon Sheet Glass Company Limited
• Inventors: Anzaki, Toshiaki, Kunisada, Terufusa, Ogino, Etsuo
• Primary Examiner(s): Jones, Deborah
• Assistant Examiner(s): MCNEIL, JENNIFER C
• Application Number:
  US09/265,417
• Time in Patent Office: 979 Days
• Field of Search: 359/359, 359/360, 359/580, 359/586, 359/588, 359/589, 428/432, 428/428, 428/696, 428/701, 428/702, 428/212, 428/216, 428/697, 428/699, 428/336, 428/343, 428/344
• US Class Current: 428/432
• CPC Class Codes: H01J 11/10 AC-PDPs with at least one main electrode being out of contact with the plasma
• CPC Class Codes: H01J 11/44 Optical arrangements or shielding arrangements, e.g. filters, black matrices, light reflecting means or electromagnetic shielding means
• CPC Class Codes: H01J 2211/446 Electromagnetic shielding means; Antistatic means
• CPC Class Codes: H01J 29/868 Screens covering the input or output face of the vessel, e.g. transparent anti-static coatings, X-ray absorbing layers
• CPC Class Codes: H05K 9/0096 for television displays, e.g. plasma display panel
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/28 Web or sheet containing structurally defined element or component and having an adhesive outermost layer
• CPC Class Codes: Y10T 428/2804 Next to metal

Abstract

An electromagnetic wave filter for a plasma display panel which is effective in preventing incorrect actions of a remote control of appliances, comprising a transparent substrate, a light transmitting electromagnetic wave shield film, and a resin protective film, wherein the electromagnetic wave shield film is a 7-layered laminate in which a dielectric layer and a metal layer containing silver as the principal ingredient are laminated alternately with the dielectric layer being the first to be provided on the transparent substrate, the dielectric layer has a refractive index of 1.6 to 2.8 at 550 nm, and the metal layer containing silver as the principal ingredient contains 0.1 atomic % or more and less than 0.5 atomic % of palladium based on silver and has a thickness of 5 to 25 nm, whereby the electromagnetic wave shield film has a sheet resistance of 3 Ω/□ or lower and a near infrared transmission of 20% or lower at 850 nm.

Claims

1. An electromagnetic wave filter for a plasma display panel comprising a transparent substrate, a light transmitting electromagnetic wave shield film coated on one surface thereof, and a resin protective film provided on the electromagnetic wave shield film, wherein said electromagnetic wave shield film is a 7-layered laminate in which a dielectric layer and a metal layer containing silver as the principal ingredient are laminated alternately, with the dielectric layer being the first to be provided on said transparent substrate, said dielectric layer has a refractive index of 1.6 to 2.8 at a wavelength of 550 nm, and said metal layer containing silver as the principal ingredient contains 0.1 atomic % or more and less than 0.5 atomic % of palladium based on silver and has a thickness of 5 to 25 nm, whereby said electromagnetic wave shield film has a sheet resistance of 3 Ω

/□

or lower and a near infrared transmission of 20% or lower at a wavelength of 850 nm.

2. The electromagnetic wave filter as claimed in claim 1, wherein said dielectric layer has a controlled thickness such that said electromagnetic wave filter has a visible light transmission of 60% or higher.

3. The electromagnetic wave filter as claimed in claim 1, wherein said metal layer containing silver as the principal ingredient each has a thickness of 5 to 16 nm.

4. The electromagnetic wave filter as claimed in claim 1, wherein the second metal layer containing silver as the principal ingredient as counted from the transparent substrate has a thickness larger than that of the first and third metal layers containing silver as the principal ingredient as counted from the transparent substrate.

5. The electromagnetic wave filter as claimed in claim 1, wherein the second and third dielectric layers as counted from the transparent substrate each have a thickness larger than that of the first or fourth dielectric layers as counted from the transparent substrate.

6. The electromagnetic wave filter as claimed in claim 5, wherein said first and fourth dielectric layers are substantially equal in thickness, said second and third dielectric layers are substantially equal in thickness, and the thickness of said second and third dielectric layers is 1.3 to 1.9 times the thickness of said first or fourth dielectric layers.

7. The electromagnetic wave filter as claimed in claim 1, wherein said dielectric layer is a metal layer containing zinc oxide as the principal ingredient.

8. The electromagnetic wave filter as claimed in claim 1, wherein at least the outermost dielectric layer of four dielectric layers has a multilayer structure comprising a tin oxide layer and a metal layer containing zinc oxide as the principal ingredient.

9. The electromagnetic wave filter as claimed in claim 8, wherein the four dielectric layers each have a multilayer structure comprising a tin oxide layer and a metal layer containing zinc oxide as the principal ingredient, with said metal layer containing zinc oxide as the principal ingredient being in contact with the metal layer containing silver as the principal ingredient.

10. The electromagnetic wave filter as claimed in claim 1, wherein said resin film has a refractive index of 1.59 to 1.69 at a wavelength of 550 nm.

11. The electromagnetic wave filter as claimed in claim 1, wherein said resin film is adhered to said electromagnetic wave shield film via a pressure-sensitive adhesive layer having a thickness of 10 to 500 μ

m.