Light attenuating anti-reflection coating including electrically conductive layers

• US 5,541,770 A
• Filed: 09/30/1994
• Issued: 07/30/1996
• Est. Priority Date: 02/19/1993
• Status: Expired due to Fees

• Current Assignee: Photran Corporation
• Original Assignee: Photran Corporation
• Inventors: Stevenson, David E., Pellicori, Samuel F.
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): Sgantzos, Mark
• Application Number:
  US08/316,037
• Time in Patent Office: 669 Days
• Field of Search: 359/585, 359/586, 359/588, 359/589
• US Class Current: 359/585
• CPC Class Codes: G02B 1/116 including electrically conducting layers
• 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

Abstract

An anti-reflection coating includes a first layer of a transparent material having a low refractive index a second layer of an absorbing metal, a third layer of a material which may have a high or a low refractive index and a fourth layer of titanium nitride.

Claims

1. An anti-reflection coating for a substrate, comprising:

at least first second third and fourth layers, said layers numbered in consecutive numerical order beginning with the layer furthest from the substrate;

said first layer including a having a refractive index between about 1.35 and 1.7 and an extinction coefficient less than about 0.1 at a wavelength of about 520 nanometers, said first layer having an optical thickness of about one-quarter wavelength of visible light;

said second layer being a layer of chromium having a thickness between about 0.5 and 5.0 nanometers;

said third layer including a material having a refractive index between about 1.35 and 2.65 and an extinction coefficient less than about 0.1 at a wavelength of about 520 nanometers, said third layer having an optical thickness less than about one-quarter wavelength of visible light; and

said fourth layer including titanium nitride and having a thickness between about 10.0 and 40.0 nanometers.

2. An anti-reflection coating for a substrate, comprising:

at least first second third and fourth layers, said layers numbered in consecutive numerical order beginning with the layer furthest from the substrate;

said first layer having a refractive index between about 1.35 and 1.7 and an extinction coefficient less than about 0.1 at a wavelength of about 520 nanometers, said first layer having an optical thickness of about one-quarter wavelength of visible light;

said second layer being a layer of molybdenum having a thickness between about 0.5 and 5.0 nanometers;

said third layer including a material having a refractive index between about 1.35 and 2.65 and an extinction coefficient less than about 0.1 at a wavelength of about 520 nanometers, said third layer having an optical thickness less than about one-quarter wavelength of visible light; and

said fourth layer including titanium nitride and having a thickness between about 10.0 and 40.0 nanometers.