JPS5911173B2 - light amplification panel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas discharge type optical amplification panel.

A conventional optical amplification panel is shown in FIGS. 1 and 2.

FIG. 1 shows a device capable of both DC and AC drive, and FIG. 2 shows a device capable of AC drive only.

In terms of structure, both FIG. 1 and FIG. 2 are completely the same except for the light shielding film.

First, in FIG. 1, a photoconductive layer 3 is formed on a glass substrate 2 on the incident light side on which a transparent electrode 1 is deposited, and then a metal light-shielding film 4, a spacer/cell separation layer 5, and a transparent electrode 6 are deposited thereon. The light emitting side glass substrates 7 are stacked one after another, and the periphery is sealed and hermetically sealed with a sealing material 8.

A rare gas or the like is sealed in advance in the light emitting cell 9 before sealing, and each gas emits light in the color of the spectrum emitted during discharge.

Furthermore, the one shown in FIG. 2 uses a dielectric light shielding film 10 instead of the metal light shielding film 4 shown in FIG.

In these devices, a voltage is applied between the transparent electrodes 1 and 6, and the applied voltage must be higher than the firing voltage of each cell 9.

When a light amplification panel having such a configuration is irradiated with light having brightness information from the glass substrate 2 side on the incident light side, the resistance value of the photoconductive layer 3 corresponding to each discharge cell 9 changes depending on the brightness.

Since each discharge cell 9 and the photoconductive layer 3 are connected in series to the power source, the discharge current of each discharge cell 9 is subject to change due to a change in resistance.

Therefore, this appears as a change in the light emission brightness or a change in the light emission area of each cell 9, and information on the brightness and darkness of the incident light is amplified and reproduced on the light emission side glass substrate T.

In this case, the incident light side glass substrate 2, the transparent electrode 1
The photoconductive layer 3 and the light-shielding film 4 are collectively referred to as a control section, and the photoconductive layer 3, which is the center of the control section, is made of a material sensitive in the visible light region, such as polyvinyl Rubazole, which is an organic optical semiconductor. Alternatively, a sintered body of inorganic CdS can be used.

However, the former has problems such as not being able to draw a large current because the impedance changes in a high region, having a narrow operating temperature range, and deteriorating quickly and quickly deteriorating characteristics, making it impractical for use in optical amplification panels.

On the other hand, CdS sintered bodies vary in impedance over a wide range from low impedance (several KΩ) to high impedance (several 10 M2), which means that they have good photosensitivity and can be controlled by the type and amount of impurities added. Also, since it is currently used in various fields and maintains relatively stable characteristics, it is considered to be optimal for use in optical amplification panels.

However, this CdS sintered body has the following essential problems.

In other words, since it is a sintered body, microcracks occur everywhere, and in the method shown in FIG. However, at this time, indium also enters into these microcracks, causing a short circuit between the transparent electrode 1 and the metal light-shielding film 4, resulting in an uncontrollable state.

One possible way to prevent this is to apply a thick layer of photoconductive layer 3, but experiments have shown that it becomes even worse.

There is also a method of forming the CdS layer several times, such as two or three times, but microcracks cannot be completely eliminated.

Furthermore, in the method shown in FIG. 2, the light shielding film 10 with a certain thickness is required to block light, or if there is a pinhole in the light shielding film 10, the pinhole and the CdS microcluster. Transparent electrode 1 through the
, 6, so a certain amount of thickness is required to eliminate pinholes.For these reasons, the light shielding film 10 tends to be thick, which causes the problem that the applied voltage becomes high. arise.

As described above, the conventional method has the above-mentioned problems and is not practical.

Therefore, it is an object of the present invention to provide a light amplification panel that is not adversely affected by cracks in the photoconductive layer.

An embodiment of this invention is shown in FIGS. 3 and 4.

This optical amplification panel has Cd on the glass substrate 2 on the incident light side.
A photoconductive layer 3 of S is formed by sintering to a substantially uniform thickness over the entire surface, and a voltage application electrode 11 as a main electrode and a discharge electrode 12 as an auxiliary electrode separated for each discharge cell 9 are formed thereon.
are formed on the same plane by vapor deposition or melt-pressure bonding with an ohmic contact material such as indium, and further, the parts other than the discharge electrode 12 are covered with a dielectric light-shielding film 10 and a spacer/cell separation layer 5, and a transparent It consists of a light-emitting side glass substrate 7 on which an electrode 6 is deposited.

As the driving voltage, a direct current or an alternating current is applied between the voltage application electrode 11 and the transparent electrode 6.

In this case, the control section includes the glass substrate 2 on the incident light side, the photoconductive layer 3
, a voltage applying electrode 11, a discharge electrode 12, and a light shielding film 10.

In the control section of this configuration, the control of the discharge current of each cell is different from the conventional method, and the surface resistance of the CdS layer 3 between the voltage application electrode 11 and the discharge electrode 12 of each cell 9 changes depending on the brightness of the incident light. Since there is no metal light-shielding film on the CdS photoconductive layer that takes part in control as in the past, there is no possibility of short circuits due to cracks.

That is, the discharge of each cell 9 occurs between the discharge electrode 12 and the transparent electrode 6.

In the embodiment, the discharge electrodes 12 separated for each cell 9 are rectangular, but this may be any shape.

Generally, the resistance change of the control section depends on the thickness of the CdS layer 3, the distance between the voltage application electrode 11 and the discharge electrode 12, the shape, the size, etc., but these depend on the voltage applied to each cell 9 or the flow Must be designed with current in mind.

It goes without saying that the light shielding film 10 can be omitted by using an opaque material as the spacer/cell separation layer 5.

Next, another embodiment is shown in FIG.

FIG. 5 has exactly the same configuration as FIG. 3 except for the light shielding film 10, and therefore the operating principle is also the same.

The light shielding film 10 is made of a dielectric material, and its purpose is mainly to protect the deposited discharge electrode 12 rather than a light shielding effect.
Light shielding is mainly performed by the spacer/cell separation layer 5.

Of course, the applied voltage must be alternating current.

Next, still other embodiments are shown in FIGS. 6 and 7.

In this optical amplification panel, the method shown in Fig. 3 inevitably requires the discharge electrode 12, voltage application electrode 11, and CdS control section on the same plane, which reduces the discharge area and makes it difficult to obtain a bright screen as a whole. This is to solve the problem.

In this case, a new discharge electrode 13 is further formed for each cell on the light-shielding film 10 of FIG. 3, and the discharge electrode 12 is electrically connected to the discharge electrode 12 using a conductive adhesive 14.

At this time, the new discharge electrode 13 can be made larger than the discharge electrode 12, so the total discharge area becomes wider.
Get a bright screen.

As described above, the optical amplification panel of the present invention includes a photoconductor layer, a main electrode and an auxiliary electrode formed separately on the photoconductor layer, and a main electrode and an auxiliary electrode arranged on the main electrode and the auxiliary electrode. The light-shielding film, the transparent counter electrode, and means for applying a voltage between the transparent counter electrode and the main electrode in order to cause discharge between the transparent counter electrode and the auxiliary electrode are provided. Not affected by cracks.

[Brief explanation of the drawing]

1 and 2 are side sectional views of a conventional example, FIG. 3 is a side sectional view of an embodiment of the present invention, and FIG. 4 is a 1000-sided cutaway view thereof.
FIG. 5 is a side sectional view of another embodiment, FIG. 6 is a side sectional view of still another embodiment, and FIG. 7 is a cutaway plan view thereof. 2... Glass substrate on incident light side, 3... Photoconductive layer, 6... Transparent electrode, 10... Light shielding film, 11...・Voltage application electrode, 12...
・Discharge electricity too

Claims (1)

[Claims] 1. A photoconductor layer, a main electrode and an auxiliary electrode formed separately on the photoconductor layer, a light shielding film and a transparent counter electrode arranged on the main electrode and the auxiliary electrode, and a transparent counter electrode. and a light amplification panel comprising means for applying a voltage between the transparent counter electrode and the main electrode to cause discharge between the auxiliary electrodes.