GLASS TUBES FOR LAMPS, METHOD FOR MANUFACTURING THE SAME, AND LAMPS

Abstract

A glass tube for lamp includes: a tubular glass section having open ends; and a ceramics film that covers at least a portion of an inner surface of the glass section in an area that forms a light emission section of the lamp.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view (with a cross section in part thereof) schematically showing a lamp in accordance with an embodiment of the invention.

FIG. 2 is a cross-sectional view schematically showing a glass tube for lamp in accordance with an embodiment of the invention.

FIG. 3 is a cross-sectional view schematically showing a step of a method for manufacturing a glass tube for lamp in accordance with an embodiment of the invention.

FIG. 4 is a view schematically showing a step of the method for manufacturing a glass tube for lamp in accordance with the embodiment of the invention.

FIG. 5 is a view schematically showing an apparatus for manufacturing a glass tube for lamp in accordance with a modified example of the embodiment.

FIG. 6 is a view schematically showing an apparatus for manufacturing a glass tube for lamp in accordance with a modified example of the embodiment.

Claims

1. A glass tube for lamp, comprising: a tubular glass section having open ends; anda ceramics film that covers at least a portion of an inner surface of the glass section in an area that forms a light emission section of the lamp.

2. A glass tube for lamp according to claim 1, wherein the ceramics film includes at least one of a compound material of boron nitride and silicon nitride, a compound material of boron oxinitride and silicon oxinitride, magnesium oxide, and yttrium oxide.

3. A glass tube for lamp according to claim 1, wherein the ceramics film entirely covers the inner surface of the glass section in the area that forms the light emission section.

4. A glass tube for lamp according to claim 1, wherein the glass section in the area that forms the light emission section has a diameter that is greater than a diameter of the glass section on other areas.

5. A glass tube for lamp according to claim 4, wherein the ceramics film entirely covers the inner surface of the glass section in the other areas.

6. A glass tube for lamp according to claim 1, wherein the ceramics film in the area that forms the light emission section has a film thickness that is smaller than a film thickness of the glass section in the area that forms the light emission section.

7. A lamp comprising the glass tube for lamp set forth in claim 1.

8. A method for manufacturing a glass tube for lamp, the method comprising the steps of: preparing a tubular glass section that opens on both ends thereof andforming by a CVD method a ceramics film that covers at least a portion of an inner surface of the glass section in an area that forms a light emission section of the lamp.

9. A method for manufacturing a glass tube for lamp according to claim 8, wherein the CVD method is one of a thermal CVD method and a plasma CVI) method.

10. A method for manufacturing a glass tube for lamp according to claim 8, wherein the CVD method uses at least one of bis (6-ethyl-2,2-dimethyl-3,5-decanodionate) magnesium, tris (sec-butylcyclopentadienyl) yttrium, and tris(trimethylsiloxy) borate as a raw material gas.