Mirror coating

• US 5,528,422 A
• Filed: 12/07/1993
• Issued: 06/18/1996
• Est. Priority Date: 12/07/1993
• Status: Expired due to Term

• Current Assignee: K W Muth Company Incorporated (K. W. Muth)
• Original Assignee: K W Muth Company Incorporated (K. W. Muth)
• Inventors: Roberts, John K.
• Primary Examiner(s): Shafer, Ricky D.
• Application Number:
  US08/163,838
• Time in Patent Office: 924 Days
• Field of Search: 359/583, 359/584, 359/585, 359/586, 359/588, 359/589, 359/603, 359/608, 359/839, 359/884, 359/634, 359/359, 359/360
• US Class Current: 359/583
• CPC Class Codes: B60Q 1/2665 on rear-view mirrors lighting devices for vehicle interior on or for rear-view mirrors B60Q3/258
• CPC Class Codes: B60R 1/08 involving special optical features, e.g. avoiding blind spots , e.g. convex mirrors; Side-by-side associations of rear-view and other mirrors B60R1/025, B60R1/10 take precedence
• CPC Class Codes: B60R 1/1207 with lamps; with turn indicators
• CPC Class Codes: B60R 2001/1223 with sensors or transducers
• CPC Class Codes: G02B 5/0833 comprising inorganic materials only
• CPC Class Codes: G02B 5/124 plural reflecting elements forming part of a unitary plate or sheet

Abstract

A mirror coating which possesses properties which are advantageous for the construction of a mirror assembly. The mirror coating has a complex reflective index which is wavelength dependent, and wherein the real component is dominant and the imaginary component is negligible within a predetermined spectral band pass region, and the imaginary component is substantially within a spectral region other than the predetermined spectral band pass region, and wherein the mirror coating exhibits substantially neutral reflected chromaticity as observed with reflected ambient light.

Claims

1. A mirror coating comprising a recurring succession of two materials which have individually variable thicknesses, and which form a layered interference filter structure, and wherein the mirror coating exhibits substantially neutral reflected chromaticity as observed with reflected visible light, has a peak transmittance of not less than 60% within a predetermined spectral band pass region, has a peak absorbance of not less than 30% within a spectral region other than the predetermined spectral band pass region, and which simultaneously has a luminous reflectance greater than 50% for the visible light striking the mirror coating, and wherein the recurring succession of materials comprises:

a first layer of ferric oxide having a thickness dimension of about 145.30 nanometers;

a second layer of silicon dioxide having a thickness dimension of about 72.89 nanometers;

a third layer of ferric oxide having a thickness dimension of about 54.14 nanometers;

a fourth layer of silicon dioxide having a thickness dimension of about 43.74 nanometers;

a fifth layer of ferric oxide having a thickness dimension of about 26.0 nanometers;

a sixth layer of silicon dioxide having a thickness dimension of about 133.60 nanometers; and

a seventh layer of ferric oxide having a thickness dimension of about 85.79 nanometers.

2. A mirror composition as claimed in claim 1, and wherein the thickness dimension of the individual layers may vary by about 2% or less.

3. A mirror coating comprising a recurring succession of two materials which have individually variable thicknesses, and which form a layered interference filter structure, and wherein the mirror coating exhibits substantially neutral reflected chromaticity as observed with reflected visible light, has a peak transmittance of not less than 60% within a predetermined spectral band pass region, has a peak absorbance of not less than 30% within a spectral region other than the predetermined spectral band pass region, and which simultaneously has a luminous reflectance of greater than 50% for the visible light striking the mirror coating, and wherein the recurring succession of materials comprises:

a first layer of ferric oxide having a thickness dimension of about 153.81 nanometers;

a second layer of silicon oxide having a thickness dimension of about 60.73 nanometers;

a third layer of ferric oxide having a thickness dimension of about 56.13 nanometers;

a fourth layer of silicon dioxide having a thickness dimension of about 37.96 nanometers;

a fifth layer of ferric oxide having a thickness dimension of about 35.61 nanometers;

a sixth layer of silicon dioxide having a thickness dimension of about 131.71 nanometers;

a seventh layer of ferric oxide having a thickness dimension of about 89.84 nanometers; and

an eighth layer of silicon dioxide having a thickness dimension of about 144.84 nanometers.

4. A mirror composition as claimed in claim 3, and wherein the thickness dimension of the individual layers may vary by about 2% or less.