Incandescent lamp with film of alternately stacked layers

• US 4,524,410 A
• Filed: 09/23/1983
• Issued: 06/18/1985
• Est. Priority Date: 09/28/1982
• Status: Expired due to Term

• Current Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
• Original Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
• Inventors: Kawakatsu, Akira, Yamamoto, Fumio
• Primary Examiner(s): Nelson, Peter A.
• Application Number:
  US06/535,162
• Time in Patent Office: 634 Days
• Field of Search: 313/112, 362/2, 362/255, 362/267, 362/293, 362/297
• US Class Current: 362/255
• CPC Class Codes: H01K 1/32 provided with coatings on the walls; Vessels or coatings thereon characterised by the material thereof

Abstract

An incandescent lamp has a bulb with a built-in filament therein, and an infrared ray reflection film formed on one or both of the outer and inner surfaces of the bulb and containing a non-crystalline metal oxide. The infrared ray reflection film is excellent in transmittance of visible rays and in reflectance of infrared rays and does not cause separation.

Claims

1. An incandescent lamp comprising:

a glass bulb having a built-in filament; and

a transparent film formed on at least one surface of said bulb, said transparent film having a structure containing at least three layers wherein a first layer comprising a non-crystalline metal oxide and having a first reflectivity and a second layer comprising a metal oxide and having a second reflectivity which is different from said first reflectivity are alternately stacked.

2. An incandescent lamp according to claim 1, wherein said first layer comprises not less than about 50% by weight of non-crystalline titanium dioxide.

3. An incandescent lamp according to claim 2, wherein said metal oxide forming said second layer is a non-crystalline metal oxide.

4. An incandescent lamp according to claim 3, wherein said second layer is formed of non-crystalline silicon.