JPS6182660A - Halogen 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 [Technical Field of the Invention] The present invention relates to a halogen light bulb that is highly efficient and capable of providing uniform illumination.

[Technical background of the invention and its problems]

For example, a halogen light bulb for a copying machine has a plurality of tungsten filaments connected in series through a short-circuit wire and concentrically sealed in a tubular quartz envelope. This light bulb contains a large amount of infrared rays in the emitted light, which may burn out the original.

Therefore, a visible light transmitting infrared reflecting film is provided on either the outside or the outside of the envelope to block infrared radiation, and the reflected infrared rays are returned to the filament to heat it and achieve high efficiency. was developed. This bulb is highly efficient, as there is little infrared rays in the emitted light, so there is no risk of burning the original.Also, in order to make the illumination distribution uniform on the irradiation surface, the filament light emitting part is discontinuous. However, this arrangement is insufficient and does not take full advantage of the characteristics of the high-efficiency halogen bulb. A technology has been developed to make the infrared radiation less intimidating and more efficient by providing a similar visible ()° C. transmitting infrared reflecting film on either the inside or outside of the envelope of a small sealed halogen light bulb.

When such a '1π star is used in combination with a reflecting mirror, an optical image of the filament 1- appears on the ray surface, which has the disadvantage that the illuminance distribution becomes non-uniform.

In contrast, the applicant first formed a visible light transmitting infrared reflective film on the outer surface of the transparent envelope, and provided a light scattering film on the infrared reflective film to diffuse the visible light that passed through the infrared reflective film. A technique was developed to uniformize the illumination distribution on the irradiated surface by diffusing the light through a film and proposed it in Japanese Patent Application No. 1983-95001. However, when this technology is applied to halogen bulbs, the bulb's envelope temperature is extremely high, so depending on the type of diffuser film, there is a risk that the diffuser film may peel off due to repeated flashing over a long period of time. It was necessary to select a light-diffusing film.

[Purpose of the invention]

The present invention provides a halogen light bulb in which the diffusion film proposed in Japanese Patent Application No. 58-95001 is free from peeling even after repeated flashing for a long period of time without impairing the effect of the proposal by adding necessary limitations to the diffusion film. The purpose is to

[Summary of the Invention] By forming a porous light scattering film on the visible light transmitting infrared reflecting film provided on the outer surface of the transparent envelope, the material constituting the envelope and the structure of the light scattering film caused by the high temperature of the halogen bulb envelope can be prevented. The porous structure absorbs distortion due to the difference in thermal expansion with the material, preventing peeling.

[Embodiments of the invention]

The iiY' class of the present invention will be explained with reference to the illustrated embodiments.

The figure shows an example of a halogen light bulb for a copying machine to which the present invention is applied. Vessel (1)
A visible light transmitting infrared reflective film formed on the outer surface of (3) is a porous light diffusing film formed on this reflection @ (2), (4)
, (4) are sealing parts formed by crushing and sealing both ends of the envelope (1), and (5) and (5) are these sealing parts (4).

Molybdenum introduced foil embedded in (4), (6), (6
) is connected to these introduction foils (5) and (5) to form an envelope (1).
), the inner conductors (7), (7)... are short-circuit wires (8), (8)... between these inner conductors (6), (6).
A plurality of filaments (9), (9) . 10), (
Reference numeral 10) designates caps that are connected to the introduction foils (5) and (5) via a wire (not shown) at the outer center and attached to both end surfaces of the envelope (1). The envelope (1) is filled with a necessary halogen along with an inert gas such as argon.

The infrared reflecting film (2) is made of titanium oxide (Ti02) or the like and has a high optical refractive index ff1, as schematically shown in FIG.
(2a) (Top left rehatching) and silica (SiO□)
It is a multilayer film formed by alternately layering low light refractive index layers (2b) (rehatching on the upper right), etc., and has the property of transmitting visible light well and reflecting infrared rays well due to light interference. Although shown exaggerated in Figure 1, each layer (2a),
The appropriate thickness of (2b) is 0.2 to 0.3μ.

Various types of light-diffusing film (3) can be considered.

One example is schematically shown in FIG. That is, this film (
3) has a continuous film body (31) made of metal oxide with many bubbles (32), (32)...
1) The surface has many circular concave holes (3
3).

(33)... is formed. The transmitted light is then scattered by such bubbles (32) and recesses (33).

Examples of such metal oxides include titanium oxide (Fi02), silica (Si02), and alumina (
AQ20:+), zirconia (ZrO2), zinc white (Z
nO), tantalum oxide (Ta205), oxidation! (Sn0
2), indium oxide (In20a), etc. are suitable.

Next, we will go straight from the 12 methods of making light bulbs. first.

Install the tubular halogen bulb in the usual way. On the other hand, Te1
- An organic titanium compound whose main component is pyrutitanate is dissolved in an organic solvent whose main component is acetic acid ester, and the titanium content is 2 to 10% by weight.

Viscosity approximately 1. Prepare titanium liquid adjusted to OCPS. Then, the above-mentioned halogen bulb is immersed in this titanium liquid, pulled up at a speed of about 30 cm/min, dried, and fired to form a high optical refractive index layer (2a) made of titanium oxide.

On the other hand, an organic silicon compound containing ethyl silicate as the main component is dissolved in an organic solvent containing acetate as the main component,
A silicone liquid adjusted to have a silicon content of 2 to 10% by weight and a viscosity of about 1.0 cps is prepared.

Then, the halogen bulb with the above-mentioned high optical refractive index layer (2a) formed thereon is immersed in this silicone liquid, pulled up at a speed of about 35 cm/min, dried, and fired to form the low optical refractive index layer (2b) made of silica. form. In this way, a total of about ten layers of high optical refractive index layers (2a) and low optical refractive index layers (2b) are alternately formed to constitute an infrared reflective film (2).

Furthermore, a high boiling point organic solvent such as di-2-ethylhexyl phthalate (dioctyl phthalate) is added to the above-mentioned solution of the organic titanium compound in a low boiling point organic solvent.

5 to 10% by volume of DoP (abbreviated as DoP) is added, and this is diluted to an appropriate concentration by adding a low boiling point organic solvent. Then, the halogen bulb with the above-mentioned infrared reflective film (2) formed in this solution was subjected to f1 cleaning, pulled up at a speed of 30 to 50 cm/min, dried, and baked in air at 600'C for about 5 minutes. Then, a light scattering film (3) made of titanium oxide is formed. However, the above D
OP is a colorless oily liquid with a pressure of 231
It boils at ℃ and is mutually soluble with various low-boiling point organic solvents in arbitrary proportions. Therefore, in the drying process, the low boiling point organic solvent is simply evaporated, and DOP is dispersed in the form of minute droplets in the gel-like coating film of the organic titanium compound. Then, during the firing step, the minute droplets evaporate and become bubbles, and the organic titanium compound is transformed into an oxide and the bubbles grow. In particular, bubbles near the surface form concave pores, and evaporate from within these pores, resulting in a rapid increase in diameter. However, D.O.P.
Since the evaporation temperature of the organic titanium compound and the M temperature of the organic titanium compound are close to each other, decomposition of the organic titanium compound starts in the process of the growth of bubbles and pores, and the oxide is formed while containing these bubbles and pores. It is formed on the membrane body (31). However,
If the coating film is made thicker by adjusting the viscosity of the coating liquid, air bubbles (32)
The concave hole (33) grows large, but on the other hand, the concave hole (33) grows large.
33) becomes shallower and the light expands jT! It becomes inferior in quality.

On the other hand, if the coating film is kept clean, air bubbles (32) and concave holes (3
Since 3) remains small, several layers of such thin light-diffusing films may be stacked.

According to experiments, several layers of 5 thin light-diffusing films (31) were stacked to form a light-diffusing film (3) with a thickness of about 0.5 to 1μ, and measurements using an electron microscope revealed that the light scattering film (3) was 20,000 to 60,000 per 1 mm2. bubbles (
32) and concave holes (33) are observed, and although it is thin, it has excellent light scattering properties, and the infrared reflective film (2)
No abnormality was observed either in terms of H or optical.

Next, we will explain the second function of the halogen light bulb.

Electricity is passed between the terminals (10) and (to) to cause the filaments (7) and (7) to emit light. Then, among the light emitted from filaments 1 to (7), (7), the infrared rays are reflected by the infrared reflecting film (2), and a considerable amount of it returns to the filaments (7), (7). This heats it up and helps improve its effectiveness. It also reflects infrared rays! The visible light transmitted through (2) is
3) and is emitted as scattered light. Therefore, this light bulb has a uniform illuminance distribution, and even when used in combination with one reflecting mirror, no optical image of the filament (7) appears.

Furthermore, in a single halogen bulb, there are a large number of 2 bubbles (32) and a concave hole (33) that is a modification of the 2 bubbles (33) in the diffuser 1 role (3), so the halogen bulb outer envelope C (1) is heated to a high temperature. Even if the difference in pi size expansion between the envelope (1) element and the acid f titanium of the light diffusing film (3) becomes large, the distortion will cause bubbles (32)
Since the light is absorbed by the diffuser and the concave hole (33), the diffuser film (3) will not peel off even if the light point is reduced over a long period of time. Saga 0.5
~1μ (→1 Thinness is also designed to alleviate distortion,
1 ri ν; 1 and causes no.

Next, the rated 150V 2
Diffusion film/dew (3) for 50W halogen light bulb for copying machine
) and compare the illuminance distribution in the H+I+ direction between the time of formation and the time after formation. This j+, 7 lT- is shown in Figure 1. In the figure, the horizontal axis is the distance in the axial direction between the center of the electric light 1 (0 and 0 * ■In the opposite substance and one], +Il+ 'i to the sheet (7 shown by the solid line) is diffused, and 'j (3) is +r6, which is 1 curved gland B (shown by the rupture).

) shows the respective illuminance distributions before forming the 1st beam 11;'1 (F).

This figure 17. The formation of diffused light 11;'j (3) made the illuminance distribution uniform.

Also, defeat i'61E:i (:'!) form n (around 1)
Electric fp (7) Brightness and full light weight) f! : When compared,
1) The formation of the light film (3) causes only about 2~3゛3 damage, and the loss is also small.
The characteristics of (:', ) are 4,,1y, ,+,'
A-mei can also be applied to halogen bulbs using a G-shaped glass envelope, and the arc of the T-shaped envelope can be arranged by arranging the filaments almost concentrically. ,゛G
In the case of a shaped envelope, it may be placed near the center of the spherical part.

Furthermore, the present invention provides the visible light transmitting infrared X'i! anti'17
11: T and a porous light scattering film are provided in a layered manner, and an outer v
The center of the JJ device may have neither an infrared reflective film nor a diffuser film, and may be equipped with a common tube-shaped halogen light bulb.

〔Effect of the invention〕

The halogen light bulb of the present invention has a visible light transmitting infrared reflective film on the outer surface of the transparent envelope 8, and a porous diffuser film is provided on the reflective film, so that it emits less infrared rays, has high efficiency, and can be irradiated. The illuminance distribution on the surface is uniform, there is no risk of displaying an optical image of the filament even when used in combination with a reflector, and even when the envelope is exposed to high temperatures, it does not blink repeatedly for a long period of time. There is also an advantage that there is no possibility that the light diffusing film will be used.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional first view of an embodiment of the halogen light bulb of the present invention, FIG. 2 is a schematic enlarged cross-sectional view of a portion taken along line 1114'i'i, and FIG. 3 is a model of the light-diffusing film. FIG. 4 is a graph showing the effect of the light-diffusing film of the light bulb of this example.

Claims (2)

[Claims] (1) A transparent envelope, a visible light-transmitting infrared reflective film formed on the outer surface of the envelope, a porous light-diffusing film formed on the infrared reflective film, and a central part of the envelope. A halogen light bulb characterized by comprising a filament arranged therein. (2) The halogen light bulb according to claim 1, wherein the light-diffusing film has bubbles incorporated therein to exhibit light-diffusing properties.