JPS60144718A - Optical shutter element - Google Patents

Abstract

PURPOSE:To obtain a high-reliability element of less secular change due to long-time driving by forming partially a resin on a band-shaped electrode for an optical shutter which is provided on one face, at least, of a solid light-transmissive porcelain having the electrooptic effect and the photoelastic effect and arranging polarizing plates on front and rear faces of the light-transmissive porcelain so that their axes of polarization are orthogonal to each other. CONSTITUTION:If light is irradiated from the rear of a polarizer 10, double refraction due to the electrooptic effect and the photoelastic effect is not caused and the light is intercepted by the polarizer 10 and an analyzer 11 when a voltage is not impressed between an electrode group 8 for voltage impression and a common electrode 7 which are formed on a PLZT plane plate 6; but when a voltage is impressed to the electrode group 8 for voltage impression, double refraction is caused by the electrooptic effect and the photoelastic effect, and the polarization state of the light is changed, and the light is transmitted. Double refraction on the PLZT plane plate 6 is caused by the Kerr effect as the electrooptic effect and distortion of the crystal due to an electric field, and therefore, resin films 8 are formed in parts having a large distortion quantity such as electrode end parts or the like on the surface of the PLZT plane plate 6 to reduce the distortion quantity, thus preventing degradation.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a solid-state optical shutter element that can be used in optical control equipment such as writing devices in optical printers and high-speed optical shutters in cameras. .

Conventional configurations and their problems In recent years, the development of optical-related technologies such as optical communication and optical information processing has been very active, and the development of optical components and optical control devices associated with this has become important. . Among these, a transparent substrate having an electro-optical effect is also attracting attention because it can be used as a light control device such as a shutter.

Currently known optical shutter elements are:
A flat plate of translucent porcelain such as La-doped lead zirconate titanate (PLZT) is used to create an electric field when a voltage is applied to the electrodes. ±4 with respect to the direction of
It has a structure in which it is sandwiched between polarizing plates having a polarization axis of 6°.

A conventional optical shutter element will be described below with reference to the drawings.

FIG. 1d shows an example of the configuration of a conventional optical shutter element T. 1 is PLZTY board, 2 &;LPLZT
The common electrode 3 provided on the plate 1 is 1i.

A group of electrodes for applying pressure is shown. 4 is a polarizer, 6 is an analyzer, and these are polarized in the direction of ±46° with respect to the direction of the electric field vector that occurs when a voltage is applied between the common polarization 2 and the voltage application electrode group 3. are arranged so that they are orthogonal to each other. The operation of the optical shutter element configured in this way will be described below. When no voltage is applied between the electrodes of the voltage application electrode group 3 formed on the PLZT flat plate 1 and the common electrode 2, the electro-optic effect and the optical Birefringence due to the elastic effect causes light to be interrupted by the polarizer 4 and analyzer 6, but when a voltage is applied to the voltage application electrode group 3, birefringence occurs due to the electro-optic effect and photoelastic effect. This causes a change in the polarization state of the light, which is transmitted through the child. Therefore, by applying a voltage to any part of the voltage application electrode group 3, light from any part can be transmitted, and it can be used as a writing head of an optical printer, a high-speed optical shutter, and the like.

6151 Figure b &: J,, P of 4Iq formation 1 flash in Figure 41a
This is a front view of the LZT plate portion, and shows the appearance of a portion of the optical shutter when a voltage is applied between the common electrode 2 and the voltage application electrode group 3. In the figure, the Δ section is a part of the optical shutter, and a part of the optical shutter is expanded due to the distribution of the electric field. Therefore, using the optical shutter element with the above configuration as a writing head of an optical printer,
When a voltage is applied to an arbitrary part of the voltage application electrode group 3 to transmit light from an arbitrary part and record it on a photoreceptor or the like, a problem arises in that the resolution of one dot becomes worse due to the spread of a single dot. By the way, as mentioned above, PLZT optical shading is caused by the birefringence effect, but the cause of birefringence is the Kerr effect as an electro-optic effect and the distortion of the crystal due to the electrostrictive effect. It is something. Therefore, by applying a voltage, the PLZT plate undergoes mechanical strain. In the conventional configuration diagram of FIG. 1d, the voltage application electrode group 3. ! l:, when a voltage is applied between the common electrodes 2,
The electric field intensity is concentrated at the electrode end portion of the surface of the PLZT flat plate 1, and a large strain is caused in the PLZT flat plate 11d at that portion. However, since the electric field strength is small on the surface of the PLZT flat plate 1 at the bottom of the electrode, the 1' L Z T flat plate 1 is not distorted, and there is a very large Stress was applied to the parts, making them susceptible to mechanical failure.

In the optical shutter element with the conventional configuration, a part of the optical shutter spreads and the resolution deteriorates, and a very large stress is applied to the surface of the PLZT flat plate 10 between the electrode end and the electrode bottom. , had a major problem in that it was easy to mechanically break by 1J°C.

OBJECTS OF THE INVENTION An object of the present invention is to provide a writing device for optical printers which is very effective for use in writing devices for optical printers,
Another object of the present invention is to provide an optical shutter element with crystal reliability that exhibits little change over time during long-term 1° driving.

Structure of the invention (a) The optical shutter element of the invention has an electro-optic effect;
A strip-shaped electrode is provided on at least one surface of the 144 pieces of translucent porcelain to form a light shutter, and a resin is partially formed on the strip-shaped electrode. Polarizing plates are arranged on the front and back sides of translucent porcelain so that their polarization axes make an angle of 900 degrees to each other.

As a result, areas where the electric field is concentrated and cause large distortions are fixed with resin, reducing the amount of distortion and eliminating mechanical damage.Additionally, areas with unnecessary light leakage are also fixed with resin and electrically By preventing birefringence due to distortion effects, light leakage is eliminated and a highly reliable cylindrical resolution optical shutter element r- is realized.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIGS. 2a, 2b, and 2c show the structure of an optical shutter element in an embodiment of the present invention. FIG. 2a is a block diagram of the optical shutter element of the present invention, b is a cross-sectional view between the eros in FIG. 2a, and C is a front view of the above-mentioned block diagram.
In FIG. 2, 6 is a PLZT flat plate, f7 is a common electrode, and 8 is a group of voltage application electrodes. 9 is a resin film related to the present invention. 10.11 shows a polarizer and an analyzer, and the polarization axis is set in the direction of 46 degrees with respect to the direction of the electric field vector generated when a voltage is applied between the common electrode 7 and the voltage application electrode group 8. It is configured to have.

The operation of the optical shutter element of this embodiment configured as described above will be described below.

The principle of the optical shutter element having the configuration according to the present invention is the same as that of the optical shutter element having the conventional configuration, and when light is irradiated from the rear of the polarizer in a10 of FIG. applied voltage 1fl
When no voltage is applied between the electrode group 8 and the common electrode 7, birefringence due to the electro-optic effect and photoelastic effect does not occur, and the light is blocked by the polarizer 10 and analyzer 11, but when voltage is applied When a voltage is applied to the electrode group 8, birefringence occurs due to the electro-optic effect and the photoelastic effect, the polarization state of the light changes, and the light is transmitted. As mentioned above, the birefringence caused by the PLZT flat plate 6 is caused by the Kerr effect as an electro-optic effect and the photoelastic effect, that is, the distortion of the crystal by an electric field (electrostrictive effect). , PLZT
Distortion was large at the end of the electrode of the flat plate 6 where the electric field was concentrated, and deterioration caused by long-term driving was a problem. Reference numeral 9 denotes a resin film according to the present invention, in which a resin film is formed on a portion of the surface of the PLZT flat plate 6 where the amount of strain is large, such as the electrode end portion, to alleviate the amount of strain and thereby prevent deterioration. Also,
Since almost no distortion occurs in the portion where the resin film is formed, birefringence due to the photoelastic effect does not occur. therefore,
The transmittance is lower than that of the part of the optical shutter that does not have a resin film, and the phenomenon in which the part of the optical shutter spreads as in the past is suppressed, and the resolution of one point in the part of the optical shutter is improved. do. Part B shown in Figure 2C shows a part of the optical shutter,
The spread to the periphery has become very small. In this example, a cr-Au electrode is formed on a PLZTY plate with a thickness of 400 μm by photolithography, and a polyimide-based pattern-formable resin is used as the resin on the cr-Au electrode by photolithography. , parts other than the necessary light shutter were coated with resin. cr-A
The thickness of the u-electrode is approximately 5000, and the thickness of the resin film is approximately 2μm.
Met. As a result of measuring the transmittance ratio of a part of the optical shack shown in B in FIG.
The value was 100 or more at an applied voltage of 100V. However, the electrode width of the optical shutter element having the above structure is 50 μm, and the distance between the electrodes of a part of the optical shutter is 60 μm. -! is,
As a result of conducting a long-term continuous application experiment of 70 V, IKHz square wave pulse using the above-mentioned element, it was found that the conventional element
Although a deterioration phenomenon was observed after 1,000 hours, no deterioration occurred even after one drive of 6,000 hours.

Note that in this example, Cr-A was used as the electrode material.
Although a u-electrode was used, other materials may be used, and although a polyimide resin film was used as the resin film, it is easy to assume that epoxy resin or other resins can also be used. .

Effects of the Invention As is clear from the above description, the present invention provides a strip-shaped electrode on at least one surface of solid translucent porcelain having an electro-optic effect and a photoelastic effect so as to form a light shutter. This invention relates to an optical shutter element in which a resin is partially formed on the second part, and polarizing plates are arranged on the front and back sides of the translucent porcelain so that the polarizing axes make an angle of 90 degrees to each other. Eliminates deterioration caused by optical distortion, eliminates unnecessary light,
This realizes a highly reliable, high-resolution optical shutter element that eliminates any light leakage.

[Brief explanation of the drawing]

FIG. 1a is a perspective view showing the structure of a conventional optical shutter element, FIG. 1 is a front view of the same, and FIGS. 2a and 2b. C represents the light beams 1 and 1 in the embodiments of the present invention, respectively. FIG. 6 is a perspective tooth, a partial sectional view, and a front view of the tar element. 1...PLZT flat plate, 2...Common electrode,
3... Electrode group for voltage application, 4... Polarizer, 6... Analysis-r, 6... PLZT flat plate, γ
. . . Common electrode, 8 . . . Voltage application electrode group, 9 . . . Resin film, 10, 11 . . . Polarizer and analyzer. 1st (2) (S5 Cb) 3 (S5 Cb)

Claims (2)

[Claims] (1) A strip-shaped electrode is provided on at least one surface of solid translucent porcelain having an electro-optic effect and a photoelastic effect so as to form a light beam, and a resin is partially formed on the strip-shaped electrode, Polarizing plates are placed on the front and back of the translucent porcelain so that the polarizing axes are 90 degrees from each other.
They were arranged so that they formed an angle of 0! The optical shutter element that is the hallmark of the government. (2) The optical shutter element according to claim 1, characterized in that the length 1" is formed by forming one layer over a part of the strip-shaped electrode portion and a portion of the optical shutter connected thereto.