JPH01166460A - Fluorescent lamp for display - Google Patents

Abstract

PURPOSE:To improve efficiency by a large margin by forming a discharge passage so as to keep a specific relationship between the width and depth of the discharge passage. CONSTITUTION:In a light source tube 1 with its one surface open, each one end of discharge passages 3R, 3G, 3B, 3G are provided with electrodes 5R, 5G, 5B, 5G independent of each other while respective other ends are provided with discharge holes 8R, 8G, 8B, 8G independent of each other. The open surface of the light source tube 1 is covered with a transparent plate 9. Discharge is performed between a common electrode 6 disposed to face respective dis charge holes 8 and respective independent electrodes 5. In this fluorescent lamp, the discharge passage 3 is formed to satisfy the equation W/2<=H<=2W, where W is the width and H is the depth of the discharge passage. This improves efficiency by a large margin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a fluorescent lamp mainly used in display elements such as large-sized color display devices.

[Background Art] As a light source for color displays, the applicant of the present application proposed a fluorescent lamp with an integrated discharge space as shown in FIG.

In such a lamp, the light source tube 1 is open on one side, and the inside is formed with an integrally formed partition wall 2, so that, for example, four discharge paths 3 are formed.
R, 3G, 3B, and 3G are formed. Each discharge path 3R
, 3G, 3B, and 3G are coated with phosphors with different luminescent colors (for example, 4R, 4G, 4B, and 4G) with luminescent colors of red, green, blue, and green. There is.

Anode electrodes 5R, 5G, 5B, 5G are provided at one end of each discharge path 3R, 3G, 3B, 3G, and a discharge hole communicating with an electrode chamber 7 provided with a common cathode electrode 6 is provided at the other end. 8R,
8G, 8B, and 8G are provided.

A translucent glass plate 9 is sealed to the opening surface of the light source tube 1 that becomes the display surface, and a glass bulb 10 constituting the electrode chamber 7 is attached to the outer bottom surface of the light source tube 1. are the discharge holes 8R and 8G.

It is sealed to cover 8B and 8G.

A discharge gas consisting of mercury and argon is sealed in an airtight space defined by the glass plate 9, the light source tube 1, and the glass bulb 10. Further, the above-mentioned parts are hermetically sealed using a glass lift.

By the way, various studies have been made regarding the shape and dimensions of fluorescent lamps. However, in general fluorescent lamps whose light source tubes are made of glass tubes, etc.,
When attempting to improve the efficiency of a lamp by changing the dimensions of the tube cross section, the reality is that this can only be done by changing the diameter of the glass tube.

On the other hand, in the above-mentioned fluorescent lamp, the cross-sectional shapes of the discharge paths 3R, 3G, 3B, 3G formed in the light source tube 1,
It was possible to change the width, depth, etc., and there was a possibility that the efficiency could be significantly improved compared to the -jl& fluorescent lamp.

[Object of the Invention] The present invention has been made with attention to the above points, and its object is to provide an efficient fluorescent lamp for display elements.

[Disclosure of the Invention] Discharge paths 3R, 3 of the fluorescent lamp for display elements shown in FIG.
The cross-sectional shapes of G, 3B, and 3G are shown in FIG. In the discharge path 3 having such a rectangular cross section, the width W of the discharge path 3 is
When the depth H is kept constant and the depth H is changed, how the brightness from an infinite distance in front of the discharge path changes is determined by calculation using the following method.

As shown in FIG. 3, when the inner wall of the discharge path 3 is divided into n elements, the emitted light intensity of the i-th element is 1. is the center of the positive column O
It is calculated from the distance V from the center to the element i, and the angle dL formed by the normal line to the element i, where: efficiency of converting ultraviolet rays into visible light/2: ultraviolet output of the plasma. At this time, it was assumed that the output of the positive column was constant regardless of the cross-sectional shape, and that the emission intensity of the phosphor was proportional to the intensity of ultraviolet light incident thereon.

Here, the light emitted from element i is reflected by the phosphor surface and exits from the glass plate surface. At this time, assuming that 80% of visible light is reflected by the phosphor surface and 100% of visible light is transmitted by the glass plate, the brightness was determined by integrating the amount of light exiting from the glass plate surface. The calculation results are shown as a solid line in FIG. 4, with the horizontal axis representing the ratio of the depth and width of the discharge path and the vertical axis representing the relative brightness with respect to the maximum brightness.

Similarly, the width of the discharge path is 2 mI! 1. 4mm, 8n
+ m and 10 mm, and experiment was conducted by making prototype lamps with varying depths of the discharge path of valley width. Discharge path width 4
The experiment with mm is plotted in Figure 4 in terms of relative brightness to maximum brightness. It can be seen that the experimental results are in good agreement with the calculated results. Similar results were also obtained for other discharge path widths.

It has been found that in lamps in which the ratio of the depth to width of the discharge path is 0.5 or less, the electrolytic strength becomes too high, impairing the startability of the lamp, and the lamp cannot be used as a practical lamp.

From the above results, the ratio of the depth H to the width W (H/W) of the discharge path that provides a brightness of 90% or more of the maximum brightness is between 0.5 and 2.
．． It was found to be in the range of 0.

[Effects of the Invention] As described above, the present invention forms a plurality of discharge paths using partition walls, coats a phosphor on the inner wall surface forming each discharge path, and creates an independent barrier at one end of each discharge path. A light source tube having an opening on one side, in which electrodes are arranged and independent discharge holes are provided at the other end, the opening surface is covered with a light-transmitting plate, and a common light source tube is provided so as to face each of the discharge holes. In a fluorescent lamp for a display element in which discharge is caused between an electrode and each of the independent electrodes, where W is the width of the discharge path and H is the depth, W/2≦H≦2W. By forming a discharge path therein, it was possible to provide a highly efficient fluorescent lamp for display elements.

[Brief explanation of the drawing]

FIG. 1 shows an example of the fluorescent lamp for display elements according to the present invention, (al is a plan view, (b) is a sectional view, and FIG. 2 is the fluorescent lamp for display elements shown in FIG. 1. FIG. 3 is a schematic diagram of the cross-sectional shape of the discharge path, and FIG. 4 is a characteristic diagram showing relative brightness. 1... Light source tube, 2... Partition wall. , 3...discharge path, 5
...Independent electrode, 6...Common electrode, 8...Discharge hole,
9... Translucent plate.

Claims (1)

[Claims] (1) A plurality of discharge paths are formed by partition walls, a phosphor is applied to the inner wall surface forming each discharge path, an independent electrode is provided at one end of each discharge path, and an independent electrode is provided at the other end of each discharge path. A light source tube with an opening on one side, each having independent discharge holes, the opening surface of which is covered with a transparent plate, and a common electrode provided to face each of the discharge holes and each of the independent electrodes. In a fluorescent lamp for a display element, each of which discharges a discharge, the discharge path is formed so that W/2≦H≦2W, where W is the width of the discharge path and H is the depth of the discharge path. Fluorescent lamps for display elements.