JPS5823161A - Incandescent bulb - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an incandescent lamp with reduced infrared radiation.

An incandescent light bulb's radiant energy is about 80% infrared rays and about 15% visible light. This infrared rays raise the temperature of the illuminated object, making it a spot! When used in bright or optical equipment, it becomes a hindrance.

Therefore, in order to reduce the infrared radiation by 1 m, a large number of infrared absorbing coatings (transparent conductive films) are attached to the glass surface of the bulb and the outer surface of the bulb.
The conditions of use are limited. Sufficient performance may not be obtained.

Although there are various types of infrared reflection filters, interference filters are excellent as films that have high visible light transparency, a large infrared reflection effect, and good heat resistance. If you choose the best material for the interference filter, you can get one that can withstand the pulp temperature of an incandescent light bulb of 200 to 7G (1°C).

However, since the wavelength range of the infrared rays emitted from incandescent light bulbs is wide, it is necessary to layer 20 or more thin layers to cover that range.
It was considered difficult.

The present invention was made based on the above-mentioned circumstances.
In order to expand the pulp, the thickness of the pulp is made in advance into a lath mtmm, and an interference filter is attached on top of it.
The present invention can be attached to an AT light bulb that reflects infrared 1S in a wide wavelength range with a single layer, and has good bone quality and less AM radiation. ' Since the reflection wavelength of an interference filter is given by the thickness of the filter layer and the distance from the light source, a large number of thin films of various thicknesses must be layered in order to reflect a wide range of wavelengths.

In contrast, in the present invention, by roughening the glass surface of the substrate, that is, the bulb in advance, it is possible to form films of various thicknesses with a small number of thin films. In reality, the film thickness varies from part to part, but when used in a light bulb, it was averaged out and good wavelength characteristics could be obtained.

Furthermore, the roughened glass surface of the bulb has a high adhesion strength between the bulb and the interference filter film, allowing it to withstand thermal cycles even in flashing light bulbs, better than halogen lamps for copiers. It became so.

The details of the present invention will be explained below with reference to the embodiments shown in FIGS. 1 and 512. The figure shows an exposure lamp for a copying machine to which the present invention is applied, and has a rating of 80V.

It is of 200W. In the figure, (1) is a tube-shaped bulb with an outer diameter of 8.0 cm made of quartz glass with both ends crushed and sealed.

(2) is an external glass surface of this bulb U+, and (3) is an infrared reflection filter formed on this external glass surface (2).

(4) is a filament disposed along the center line of bulb i1). The glass surface (2) is formed by dry honing the external glass surface of the bulb tU into a roughened surface with a depth of 1 to 2 μm. The above infrared reflective film (3)
For example, a multilayer film consisting of 9 layers is formed by alternately layering thin layers of titanium oxide (10.) with a large optical refractive index and thin layers of silicon dioxide (8.0.0.0) with a small optical refractive index. It is.

To form this infrared reflective film (3) 1, for example, organic titanium (T i (OR) 4 ) and organic silicon (81 (OR) 4) are diluted with a suitable solvent such as total ethyl acetate or ethanol. Light bulbs made to an appropriate viscosity and sealed with exhaust gas are alternately immersed in these solutions, pulled up at a constant rate, and baked at a temperature of about 500° C. to form a multilayer film.

In order to see the difference in the shape of the outer surface of the bulb (IIO), we prepared two types of light bulbs, a normal light bulb with a smooth outer surface and a nine light bulb with a roughened outer surface, using the same light bulbs as above, and infrared rays as described above on the outer surface. The radiant energy distribution of these prototype light bulbs was investigated by impregnating the reflection filter.The results are shown in Figure 2.In the diagram, the horizontal axis represents the wavelength t (μ), and the vertical axis represents the relative value of the radiant energy. The curve (4) is the rough surface KL mentioned above.
7, a light bulb with the above-mentioned infrared reflective filter on its outer surface, i! 1! ! (B) shows the radiation of a light bulb with the above-mentioned infrared reflective filter on its smooth outer surface, and curve M (C) shows the respective radiation values of a light bulb with a smooth outer surface 1 and no infrared reflective filter tube. It can be seen from the figure by Jin that infrared radiation in a wider wavelength range can be blocked by making the outer surface of the bulb rough. If an attempt was made to obtain a radiation spectrum tube comparable to curve m(6) in the figure by providing an infrared reflection filter on a smooth surface of a tentative lens, a 21M (0) multilayer film would be required.

Furthermore, these prototype bulbs were tested in a flashing cycle of 2 seconds on and 3 seconds off. As a result, the bulb, which had an infrared-reflecting coating on one layer with a roughened surface, showed abnormalities even after 200,000 flashes. On the other hand, a light bulb with an infrared reflective film on the smooth outer surface of the bulb flashed about 50,000 times and the infrared reflective filter cracked, and after 80,000 flashes some parts of the filter peeled off. .

In the above-mentioned embodiment, the infrared reflection filter tube was provided on the outer glass surface of the bulb, but it may also be provided on the inner glass surface of the bulb, or on both glass surfaces. The constituent material of the bulb is not limited to quartz glass, but may also be composed of high melting point glasses such as high silicate glass, silicic acid glass, and aluminosilicate glass.

Furthermore, as a material with a high optical refractive index constituting an infrared reflection filter, tin oxide (SmO,) and antemoxide (sho,) are suitable, and as a material with a low original refractive index, Calcium fluoride (CaF) 1 is known.

In this way, since the infrared reflection filter was formed on the glass mvt rough surface of the high melting point glass bulb and on the rough WJt glass surface, it was possible to form an infrared reflection filter on the glass surface of the high melting point glass bulb. An incandescent light bulb with reduced I can be provided.

[Brief explanation of the drawing]

FIG. 1 is a cross-section ff1E of an embodiment of the incandescent light bulb of the present invention. FIG. 2 is an enlarged sectional view of the main part, and FIG. 3 is a graph showing the advantages of the present invention. +11...Glass bulb (2)...Glass surface (
31... Infrared reflective film (4... Filament agent Patent attorney Inoue - Male Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A high melting point glass bulb with a rough glass surface and a plurality of transparent thin layers having different optical layer refractive indexes t' are alternately layered, and an infrared reflection filter is formed on the rough glass surface. 4! A moldy incandescent light bulb.