JPS581506B2 - mixed vapor discharge lamp - Google Patents

Description

[Detailed description of the invention] The present invention relates to improvements in mixed vapor discharge lamps.

A type of discharge lamp, a metal halide is sealed together with an inert gas for starting and mercury in an arc tube with sealed electrodes to improve efficiency and
There are mixed vapor discharge lamps with improved color rendering.

Examples of the metal halides used include thallium iodide, sodium iodide, and indium iodide.

If a metal halide that strongly emits these resonance lines is sealed in an arc tube, the color rendering properties of a discharge lamp can be improved to some extent, but it has been difficult to provide sufficient color rendering properties like an incandescent lamp.

Therefore, it was not satisfactory for general lighting.

Among metal halides, tin halide has particularly excellent color rendering properties, but the color rendering index Ra is 86 and the special color rendering index R9 for red is about 75, so that it cannot provide sufficient color rendering properties.

FIG. 2 shows the wavelength-relative spectral energy characteristics of a conventional mixed vapor discharge lamp containing tin diiodide as a tin halide.

The present invention was made in view of the above circumstances, and its object is to provide a mixed vapor discharge lamp with excellent color rendering properties.

In order to achieve the above object, according to the present invention, tin bromide is added together with mercury and an inert gas in an amount of 0.7 to 2.0 m9 per 1 ml of internal volume of the container in a translucent container in which an electrode is sealed. , calcium bromide at a concentration of 0.00% per ml of internal volume of the container.
24 to 2.5 mg was enclosed.

The present invention will be explained below with reference to the drawings.

FIG. 1 shows an example of a mixed vapor discharge lamp used in the present invention.

In the figure, an arc tube 1, which is a light-transmitting container, is supported and fixed within an outer tube 2 by a stem 3.

Inside the arc tube 1, silver bromide and calcium bromide are sealed together with an inert gas of 10 to 40 torr and mercury, and a pair of main electrodes 4, 5 and an auxiliary electrode 6 for starting are sealed. has been done.

One main electrode 4 is connected via a molybdenum foil 9 sealed to a pinch seal 7 of the arc tube 1 to a conductor 12 fixed to the stem 3 and serving as a support.

The other main electrode 5 is connected via a molybdenum foil 10 sealed to the pinch seal 8 to a conductor 13 fixed to the stem 3 and serving as a support.

The auxiliary electrode 6 is connected to a conductor 13 via a molybdenum foil 11 sealed to a pinch seal 7 and a resistor 14 .

The two conductors 12 and 13 to which the main electrodes 4 and 5 and the auxiliary electrode 6 are connected in this way are connected to the shell portion and eyelet portion of the cap 15 attached to the outer tube 1, respectively.

When a voltage is applied to the main electrodes 4 and 5 and the auxiliary electrode 6 of the mixed vapor discharge lamp configured in this way, a slight discharge first occurs between the main electrode 4 and the auxiliary electrode 6, and then the main electrodes 4 and 5 An arc discharge occurs between the two.

The arc tube 1 is heated by the heat generated by this discharge, and the vapor pressures of mercury, tin bromide, and calcium bromide rise, and the light emission gradually becomes stronger and becomes stable.

Although some of the tin bromide dissociates in the arc column and emits tin atoms, the majority remains in a molecular state.

These evaporated substances in the arc tube 1, such as tin bromide, emit a strong spectrum at the operating temperature of the arc tube, and the molecular spectrum of calcium bromide, which is the main component of the red color, overlaps with the above spectrum and emits strong light. .

Next, the present invention will be explained with reference to examples.

Example A lighting test was conducted at an input power of 400 W for each sample in which the amounts of SnBr2 and CaBr2 were varied.

As a result, SnBrs+ was 0. 7-2. 0mg
/ml and CaBr2 0.24 to 2.5mg/m
l, the average color rendering index Ra is 96 or more and 10
A discharge lamp with excellent light color was obtained with a color temperature close to 0 in the range of 3900 to 53000K.

Table 1 shows the lighting test results for each sample.

By using bromine as the halogen in the inclusion material in each of the above examples, the range including the amount of tin bromide and calcium bromide is set to 0.7 to 2.0 mg/ml for tin bromide and 0.7 to 2.0 mg/ml for calcium bromide. 0. 2 4 ~2. By enclosing 5 mg/ml, a lamp with an average color rendering index higher than that of conventional discharge lamps was obtained.

In the example, the amount of tin bromide sealed in the arc tube 1 is 0.
．． 7-2. The reason why significant changes are observed in both color rendering properties and color temperature when the amount of calcium bromide is in the range of 0.24 to 2.5 mg/ml is as follows.

That is, calcium bromide has a vapor pressure of 800°C, which is higher than the tube wall temperature of a normal lamp (approximately 550°C).

On the other hand, tin bromide has a low vapor pressure and is easily decomposed at the tube wall temperature.

The amount of calcium that combines with this bromine has a great effect on high color rendering properties and color temperature, so the minimum amount was determined to balance the amount of bromine that is produced when tin bromide vaporizes and decomposes. Ta.

The upper limit was determined as an amount that does not interfere with the stability of the arc, since an increased amount of calcium, an alkaline earth element, lowers the arc temperature.

The tin, calcium, and bromine sealed in the arc tube 1 are as follows:
In addition to being encapsulated in the form of tin halide and calcium halide as in the above embodiment, a part or all of the halogen may be encapsulated in a form combined with mercury together with tin and calcium alone.

According to the present invention described in detail above, in a translucent container in which a pair of electrodes are sealed, along with mercury and an inert gas, one of the fillers contains tin bromide containing brominated halogen as the contents of the container. 0.7 to 2.0 mg per ml of volume, and 0.24 to 2.5 mg of calcium bromide per 1 ml of internal volume of the container.

Therefore, a discharge lamp with high color rendering properties can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of a discharge lamp used in the present invention;
FIG. 2 is a characteristic diagram showing the wavelength-relative spectral energy distribution of a conventional mixed vapor discharge lamp containing tin halide. 1... Arc tube, 4, 5... Main electrode, 6... Auxiliary electrode.

Claims (1)

[Claims] 1. In a translucent container with an electrode sealed, tin bromide was added together with mercury and an inert gas at a concentration of 0.00% per ml of internal volume of the container.
7 to 2.0 mg of calcium bromide and 0.24 to 2.5 mg of calcium bromide per 1 ml of internal volume of the container.