Optical device having low visual light transmission and low visual light reflection

A solar control film having low visible light transmittance and low visible light reflectance is comprised of two or more transparent substrates each bearing a thin, transparent, discontinuous, incoherent film of metal having low visible light reflectance and a degree of visible light blocking capacity, the substrates being so assembled and laminated into a composite that the visible light blocking capacities of the metal films are effectively combined to provide a composite having low visible light transmittance. Performance characteristics are enhanced by providing on one or more of the substrates a transparent coating of high refractive index underlying the metal film. The material of high refractive index is preferably a synthetic high oxygen content oxide of bismuth, which facilitates efficient and economical production of the solar control film.

Latest MSC Specialty Films, Inc. Patents:

Skip to:  ·  Claims  ·  References Cited  · Patent History  ·  Patent History

Claims

2. A solar control film as set forth in claim 1 wherein at least one of said sheets of substrate material bears a layer of material of high refractive index between the substrate and the incoherent film of metal for further controlling the visible light transmittance and visible light reflectance of the composite film.

3. A solar control film as set forth in claim 2 wherein the material of high refractive index is selected from silicon nitride, the oxides of chromium, niobium and titanium, and a synthesized oxide of bismuth having an atomic ratio of oxygen to bismuth of from about 1.7 to about 2.5.

5. A solar control film as set forth in claim 1 including a third sheet of transparent substrate material having thereon a thin, incoherent, transparent film of metal effective to partially block visible light transmittance and having substantially the same low visible light reflectance as the other incoherent films, said third sheet being sandwiched between and physically bonded to said first and second sheets with the incoherent film of metal thereon separated from and optically decoupled from the incoherent films of metal on said first and second sheets.

6. A solar control film as set forth in claim 5 wherein one, two or all of said sheets of substrate material bears a layer of material of high refractive index between the substrate and the incoherent film of metal for further controlling the visible light transmittance and visible light reflectance of the composite film.

7. A solar control film as set forth in claim 1 including a layer of pressure sensitive adhesive on one side of the composite film for bonding the same to a window and a protective coating on the other side of the composite film for protecting the film from damage.

9. A solar control film as set forth in claim 8 including a third sheet of transparent substrate material bearing thereon a thin, incoherent, transparent coating of metal effective to partially block visible light transmittance through the coated substrate and having substantially the same low visible light reflectance as the other incoherent films, said third sheet being sandwiched between and physically bonded to said first and second sheets with the incoherent film of metal thereon separated and optically decoupled from the incoherent films of metal on said first and second sheets.

10. A solar control film as set forth in claim 8 wherein the material of high refractive index comprises a synthesized oxide of bismuth reactively sputter deposited on the substrate material and having an atomic ratio of oxygen to bismuth of from 1.7 to 2.5.

11. A solar control film as set forth in claim 8 wherein the material of high refractive index is selected from the oxides of chromium, niobium and titanium and silicon nitride.

13. A method as set forth in claim 12 wherein the coated substrates are laminated to one another and are separated and optically decoupled from one another by means of one or more interleaved layers of adhesive.

14. A method as set forth in claim 12 including the step of first depositing onto the substrate a thin transparent layer of material of high refractive index and then depositing the metal coating onto the material of high refractive index.

15. A method as set forth in claim 14 wherein the material of high refractive index has a refractive index of at least 2.0.

16. A method as set forth in claim 12 including the step of reactively sputter depositing onto the substrate a synthesized oxide of bismuth having an atomic ratio of oxygen to bismuth of from 1.7 to 2.5, and then sputter depositing the thin coating of metal onto the synthesized bismuth oxide..Iadd.17. A method as set forth in claim 12 wherein the metal deposited on each substrate comprises chromium, a nickel-chromium alloy or stainless steel..Iaddend..Iadd.18. A method as set forth in claim 17 wherein the metal is sputter deposited onto the substrate..Iaddend..Iadd.19. A solar control film as set forth in claim 1 wherein the metal deposited on each substrate comprises chromium, a nickel-chromium alloy or stainless steel sputter deposited onto the substrate..Iaddend..Iadd.20. A solar control film as set forth in claim 1 wherein the visible light transmission of the composite film lies within

the range of from about 20% to about 50%..Iaddend..Iadd.21. A solar control film having low visible light transmittance and low visible light reflectance comprising

a first sheet of transparent substrate material having thereon a thin, incoherent, transparent film of metal effective to partially block visible light transmittance and having a preselected low visible light reflectance,
a second sheet of transparent substrate material having thereon a thin incoherent, transparent film of metal effective to partially block visible light transmittance and having a preselected low visible light reflectance, and
a layer of adhesive bonding said first and second sheets to one another with the films of metal facing one another and separated and optically decoupled from one another,
the bonded sheets forming a composite film having a combined visible light transmittance blocking effect equal approximately to the sum of the blocking effects of the incoherent films and visible light reflectance substantially equal to the visible light reflectance of just one of the incoherent films, the composite film having on clear glass a visible light transmittance within the range of 20% to 50% and a visible light reflectance no greater than 15% when visible light transmittance is within the range of 20% to 35% and no greater than 12% when visible light transmittance is within the range of 35% to 50%..Iaddend.
Referenced Cited
U.S. Patent Documents
3556640 January 1971 Austin
4045125 August 30, 1977 Farges
4634637 January 6, 1987 Oliver et al.
4797317 January 10, 1989 Oliver et al.
4799745 January 24, 1989 Meyer et al.
4978181 December 18, 1990 Inanuma et al.
5071206 December 10, 1991 Hood et al.
5306547 April 26, 1994 Hood et al.
Foreign Patent Documents
63-265625 November 1988 JPX
Other references
  • Floyd E. Woodward et al., PCT International Publication No. WO 94/04356, Mar. 1994. 3M Scotchtint.TM. Sun Control Window Film Re2onearl, Minnesota Mining & Manufacturing Co., St. Paul, MN (1 sheet).
Patent History
Patent number: RE36308
Type: Grant
Filed: Jun 2, 1998
Date of Patent: Sep 21, 1999
Assignee: MSC Specialty Films, Inc. (San Diego, CA)
Inventor: Peter Y. Yang (San Diego, CA)
Primary Examiner: Jon Henry
Law Firm: Juettner Pyle Piontek & Underwood
Application Number: 9/88,916
Classifications
Current U.S. Class: Including Metal Or Conductive Layer (359/585); Layers Having Specified Index Of Refraction (359/586); More Than One Such Component (428/622); Oxide-containing Component (428/632)
International Classification: G02B 110; G02B 528; B21D 3900; C03C 2704;