WO1990010887A1

WO1990010887A1 - Light shutter array and method of producing the same

Info

Publication number: WO1990010887A1
Application number: PCT/JP1990/000310
Authority: WO
Inventors: Hidenori Sukigara; Kazuo Kobayashi
Original assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
Priority date: 1989-03-09
Filing date: 1990-03-09
Publication date: 1990-09-20

Abstract

The invention relates to the construction of a light shutter array utilizing an electrooptical effect and to a method of producing the same, and its object is to provide a light shutter array which is inexpensive but operates without fail at a low drive voltage. This array has a plurality of individual electrodes (3) and a common electrode (4) on each of planes (2A, 2B) in parallel with the direction of light transmission of the substrate (2) which exhibits an electrooptical effect, has a support member (5) that sandwiches the electrodes (3) between it and the substrate (2), and further has terminal electrodes (6) provided on the support member (5). According to the manufacturing method of the invention, two blocks are joined together in such a manner that the common electrodes (4) are opposed to each other back to back with an insulating material (8) interposed therebetween in order to constitute a single block, each of the above blocks having stacked thereon the individual electrodes (3) and the common electrode (4) on each of the planes (2A), (2B) in parallel with the direction of light transmission of the substrate (2) that exhibits an electrooptical effect, and further having the support member (5) for sandwiching the electrodes (3) between it and the substrate (2). The block thus constituted is sliced in the direction at right angles with the direction of stacking, and terminal electrodes (6), (7) are formed on the ends of the electrodes (3) and the common electrode (4), respectively, exposed on the sliced surfaces.

Description

Specification

Optical shutter array and method of manufacturing the same

Technical field

The present invention relates to an optical shutter array and a method for manufacturing the same. More specifically, the present invention relates to an optical shutter array utilizing an electro-optic effect and a method for producing the same.

Background art

As the electro-optic effect, a phenomenon in which the birefringence of a medium changes with respect to an applied field is known. By using this phenomenon, an optical shutter array has been proposed in which an applied electric field is controlled to allow the medium to perform light transmission / shielding operations. . This optical shutter array is composed of a plate-like substance having an electro-optic effect, such as PLZT, in which thin electrodes are arranged in a comb-like manner, and the voltage applied to each electrode is controlled to generate a predetermined electric field in the PLZT. It is intended to be applied. Conventionally, the electrode 101 is formed on the surface of PLZ L02, that is, the surfaces 102C and 102D orthogonal to the suitable light transmission direction, by aluminum deposition and etching treatment. For example, as shown in Fig. 6A, it is mounted on one surface 1G2C orthogonal to the light transmission direction of PLZT102, or as shown in Fig. 6B, it is mounted on both surfaces 1G2C, 1G2D of PLZT1G2.

(JP-A-62-42120), as shown in Fis. 6C, a groove is formed in the PLZT 102 so that the electrode 101 is partially embedded in the depth direction of the ZT 102, that is, in the light transmission direction. It is mounted. However, when the electrode 101 is formed on the surface 1G2C, which is orthogonal to the light transmission direction of the substance 102 having the electro-optical effect, the driving voltage is increased because the electro-optical effect is hard to occur uniformly inside the substance. You have to do it. Also, when a part of the electrode is embedded in the substance 102, it is difficult to process the narrow hole 103, and there is a problem that the mechanical strength of the PLZT 1 G2 is inferior due to the groove processing. However, in the conventional shutter array described above, since the lead portion 104 of the electrode 1C1 is also formed on the substance 102 having an electro-optical effect, it is necessary to have an area wider than the actual shutter portion. Therefore, the cost is high.

On the other hand, as a method of manufacturing an aerial optical element, there has been a conventional method in which a laminate of a green sheet of an electro-optic ceramic and an electrode layer is sintered and integrated (Japanese Patent Application Laid-Open No. 63-256921). ).

Disclosure of the invention

An object of the present invention is to provide a shutter array that is inexpensive and operates reliably with a low driving voltage. Another object of the present invention is to provide a manufacturing method capable of easily manufacturing a shutter array having such a structure.

In order to achieve the above object, an optical shutter array according to the present invention comprises: a substrate having an aero-optical effect; a plurality of individual electrodes provided on one surface of the substrate parallel to a light transmission direction; A common electrode provided on the other surface of the substrate parallel to the surface of the substrate; a support member for sandwiching the individual electrode between the substrate and the substrate; Connected to and the terminal electrodes are provided so that the individual electrodes and the common electrode are substantially parallel to the incident light, and the terminal electrodes are substantially orthogonal to the incident light. It has been done.

In addition, the optical shutter array of the present invention includes a step of forming a plurality of mutually independent individual electrodes on one surface parallel to the light transmission direction of a substrate having an electro-optical effect; Forming a common electrode on the other surface of the substrate, forming a support member on the individual electrode side of the substrate, and laminating the substrate, the individual electrode, the common electrode, and the support member. A step of forming one block by joining two sets of blocks with an insulating material therebetween so that the common electrode faces back to back, and forming the block perpendicular to the laminating direction. And a step of forming a corresponding terminal electrode connected to each of the individual electrodes and the common electrode. Therefore, it is parallel to the light transmission direction of the electro-optic effect element. Formed on a surface The electric field is applied between the individual electrode and the common electrode, the electro-optical effect appears uniform in the thickness direction.

Therefore, the optical shutter array of the present invention can be driven at a low voltage. In addition, since a material having an electro-optical effect, such as PZT, is used only in the shutter portion, and another ceramic member is used in the portion where the terminal electrodes are wired, the use of PLZT is small. Cost reduction is possible.

Further, the optical shutter array of the present invention has an electro-optical effect. A block is formed by joining two sets of blocks, each of which is formed by laminating an individual electrode, a common electrode, and a support member on a substrate to be bonded, such that the common electrodes face each other, and forms one block. Blocks are sliced on a surface perpendicular to the lamination direction, and the terminal electrodes are formed on the end surfaces of the individual electrodes and the common electrode exposed on the sliced surface. It can be made by the planar method, improving mass productivity.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is a plan view showing an embodiment of the optical shutter array of the present invention, and FIG. 1B is an enlarged sectional view taken along the line I-I of FIG.

f i 2 A--f i8, 2G are step diagrams showing an example of the manufacturing process of the optical shutter array according to the present invention.

Γig.3 shows another embodiment of the present invention, and is a plan view partially showing the configuration of an optical shutter array.

ίig.4A-Fig.4F is a process diagram showing an example of an electrode forming process of the optical shutter array according to the present invention.

Figure 5 shows the principle of the optical shutter.

Fig. 6A-Fig. 6C are cross-sectional front views illustrating the arrangement of the electrodes in a conventional optical shutter array.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the configuration of the present invention will be described in detail based on an embodiment shown in the drawings.

FIG. 1A and FIG. 1B show one example of the optical shutter array of the present invention. An example will be described. In this embodiment, two sets of shutter arrays 1 and 1 are joined back-to-back so that their common electrodes 4 face each other to form one block. A set of shutter arrays 1 includes a substrate 2 made of a substance having an electro-optic effect, and a plurality of individual electrodes 3,..., 3 provided on one surface 2 平行 of the substrate 2 parallel to the light passing direction. A common electrode 4 provided on the other surface 2 平行 of the substrate 2 parallel to the one surface 2 前記, and a support member 5 for sandwiching the individual electrodes 3,. .., 6 provided on the support member 5 and individually connected to each of the individual electrodes 3,..., And 3}. In the array 1, 1, insulating layers 8, 9 also serving as SiO 2 and an adhesive of low melting point glass are provided between the common electrodes 4, 4 facing each other and between each individual electrode 4 and the supporting member 5. Formed and consolidated to form one block. Also, the individual electrodes 3,..., 3 are staggered so that the individual electrodes 3,..., 3 of one support member 5 are located between the individual electrodes 3,. Have been placed. The individual electrodes 3,..., 3 are arranged at regular intervals with a constant width in the present embodiment, but are not particularly limited to these widths and intervals. The interval is set.

Each of the individual electrodes 3,..., 3 is provided with a corresponding terminal electrode 6,..., 6 formed on and connected to the support member 5 so that each individual electrode can be individually controlled. Also low One terminal electrode 7 is simultaneously connected to the common electrodes 4 and 4 joined via an adhesive 8 such as melting glass and SiO 2. The connection between the individual electrodes 3,... 3 and the terminal electrodes 6,... …, 6 are formed. The same applies to the connection between the common electrodes 4 and 4 and the terminal electrode 7. The electrodes 3 and 4 are made of an electrode material such as aluminum or a transparent electrode material such as tin oxide, and are formed to a desired shape and thickness by vacuum evaporation or the like. The common electrode 4 may not be a single electrode over the entire surface of the other surface 2B of the substrate 2 as shown in the figure, but may be formed as a plurality of electrodes corresponding to the individual electrodes 3,.

The substrate 2 having the electro-optic effect is a medium exhibiting a phenomenon that the birefringence changes in response to an applied electric field. For example, it is preferable to use PLZT. PLZT is a ceramic represented by the chemical formula (Pb, then a) (Zr, Ti) O3. For optical shutters, for example, PLZT 9Z65 / 35 is generally used. It is. This PLZT has a high transmissivity and a large electro-optic coefficient, and has favorable conditions as a high-speed optical shutter such as a fast response speed and no moving parts. In addition, as the support member 5, ceramics can be usually used, but the support member 5 is not particularly limited thereto, and may be glass or the like.

According to the shutter array configured as described above, it operates as an optical shutter as follows. The origin of the optical shutter is shown in タ 8.5. In FIG. 5, 110 is a polarizer, 111 is an analyzer, 1 is a shutter array, “Π3 is a power supply, 114 is a light source, 1 is a switch. Light incident from the light source 4 is The polarizer 110 converts the light into a linear light (I light, which is introduced into the shutter array 1). When no pressure is applied to the shutter array 1, P and ZT 2 are optically isotropic. Because it is a body, the light is blocked by the analyzer 111, and the light becomes stagnant. Also, when a voltage is applied to the shutter array, P and ZT 2 show optical anisotropy. Therefore, the light plane rotates with the transmission of the light, and the light that reaches the analyzer 111 becomes elliptically polarized light or linearly polarized light depending on the applied voltage. When a so-called half-wave power is applied, the light is rotated 90 degrees just because the half-wave phase is shifted, and the light is analyzed as a linear light. Since passing through the 11 1, the maximum of the output light intensity can be obtained

When a predetermined voltage is applied between any of the individual electrodes 3,..., 3 and the common electrode 4 by operating the switch 105, an electric field is generated between them. PLZT 2 causes birefringence and operates as a shutter. For example, when an electric field is applied between the upper rightmost individual electrode 3 and the common electrode 4 in FIG. 1A, the shutter portion A-1 of the PZT2 between them operates to transmit light. In the figure, reference numerals A-1, A-2, ..., A-Ν indicate shutter parts.

Next, a method of manufacturing the optical shutter array having the above configuration will be described. First, an electrode material such as aluminum is fixed to the entire surface 2A of the PLZT substrate 2 parallel to the light transmission direction by vacuum evaporation or the like to form a thin film 10 having a constant thickness (Fig. 2 A] <Stripe-shaped individual electrodes 3,..., 3 are formed on the A jg thin film 10 by photolithography [fig.2B]. The photolithography is performed, for example, by applying a positive type photo resist on the thin electrode material film 10 and irradiating only a portion where the electrode material is not required with a photo mask. UV light is passed through the electrode to remove the photosensitizer with a developer, use the remaining photosensitizer as a protective film, and partially remove the electrode material 1G by etching. The photosensitizer is removed. Also, an electrode material such as Α is fixed to the other surface 2 B (back surface) of the substrate 2 parallel to the light transmission direction by vacuum evaporation or the like, and the common electrode 4 is formed on the entire surface. ]. In this case, the common electrode 4 may be formed only in a portion corresponding to the individual electrode by the same method as the individual electrodes 3,. If the common electrode 4 is provided separately at a position facing the individual electrodes 3,..., 3, the difference in expansion due to ripening when the insulating layers 8, 8 are bonded to each other causes the thinning of the common electrode and Si 02 The danger of peeling can be reduced, and since the electro-optical effect does not spread laterally at the common electrode portion, crosstalk can be prevented. Then, thin films 8 and 9 of Si 02 as an insulating material are formed by sputtering or the like so as to cover the electrodes 3,. [F Ί g .21)] _Φ Next, two sets of the above-mentioned blocks 11 are butted back to back so that the common electrodes 4, 4 face each other, and the individual electrodes 3,..., 3 on one support member 5 support the other. The members 5 are arranged in a staggered manner so as to be located between the individual electrodes 3,..., 3, and a spacer (not shown) is sandwiched between the common electrodes 4. Further, a block of ceramics or the like as the support member 5 is stacked on each of the individual electrodes 3,..., 3 via a spacer (not shown). After that, the low-melting-point glass 12 is allowed to penetrate between the support member 5 and the individual electrode measurement insulating layer 9 and between the common electrode side insulating layer 8 in a ripened state, and the whole is formed into one block. Harden [fig.2 Ε].

The block 1 3 laminated direction, that is P and by slice in light transmission over a direction perpendicular to the direction 1 8 of ZT substrate 2 is "F ί g .2 F] _¾ slice to desired thickness The block chip 14 is polished, and an electrode material such as aluminum is formed into a thin film by vacuum deposition or the like on one surface of a surface orthogonal to the light transmission direction of the block chip 14. The desired terminal electrodes 6,..., 6 are formed on the support member 5 by photolithography and the terminal electrodes 7 are formed on the common electrodes 4, 4. [ig.2G The terminal electrodes 6,…, 6 are connected to the corresponding individual electrodes 3,…, 3 respectively, and the terminal electrode 7 is connected to both common electrodes 4, 4 at the same time. The optical shutter array of this embodiment is different from that of fi9.1 in that the individual electrodes 3,..., 3 are formed on a surface 2A parallel to the light passing direction of the substrate 2. Multiple of 瀵部 1 5, …, They differ in that they are embedded electrodes formed by embedding a conductive metal in 15. In the case of this optical shutter array, the surface of the substrate 2 after the formation of the individual electrodes, that is, one surface 2 平行 parallel to the light transmission direction of the substrate 2 is planarized, and the surface of the insulating layer 9 formed thereon is coated. Is prevented from becoming M convex, and uneven bonding at the time of bonding to the support member 5J, generation of stress distribution in the substrate 2 after bonding, and the like are prevented.

Next, Fig.4 shows the method of forming the individual electrodes 3, ..., 3 in the optical shutter array having the configuration of fig.3.

First, a PLZT (9/65/35) and whether Ranaru substrate 2 having an electro-optic effect [Fig.4 A] _¾ Next, on one surface 2 A light transmitting direction parallel to the substrate 2 A pattern for an embedded electrode is formed in a strip shape by a photolithography method or the like. More specifically, for example, a positive photoresist (photosensitive agent) 16 is uniformly applied to one surface 2A of the substrate 2 so that the individual electrodes 3,..., 3 are not required. UV light is irradiated through a photomask so that only the light is radiated, the photosensitive agent 16 in the exposed area is removed by the developing solution, and the photosensitive agent 16 is left by the remaining photosensitive agent. A pattern for an embedded electrode is formed on tripe [fig.4B].

Next, using the remaining photosensitive agent 16 as a protective film, an etching technique (dry etching, wet etching) is used to form a 滂 portion 15 on the substrate 2 [Hg.4C]. Then, a conductive metal serving as an embedded electrode 3 is formed on the substrate 2 on which the upper portion 15 is formed. (AI, AI, Ag, Cu, Ni, Mo, W, etc.) is coated using a technique such as vacuum deposition, sputtering, and plating [[ig. 4]. I)〗. After that, the photosensitive agent 16 used as the protective film is removed to remove the conductive metal 17 other than the conductive metal 17 adhered to the portion 15 and the conductive material remaining in the portion 15 is removed. Let the metal be the individual electrodes 3, ..., 3 [fig. 4 E]. That is, when the substrate 2 after the formation of the conductive metal film shown in ΙΊ8.4 L> is put in a solution in which the photosensitive agent 16 is dissolved, the conductive metal 17 on the photosensitive agent becomes the photosensitive agent 16. Both are peeled off, and only the conductive metal 17 in the upper part 15 remains on the substrate 2 to form the embedded electrode 3.

According to this method, the surface of the substrate 2 will not be flat unless the depth of the groove 15 and the thickness of the conductive metal 17 are equal. Therefore, in such a case, it is preferable to flatten the substrate surface by lapping or the like.

As shown in Fίg. 4 E, the insulating layer 9 is formed on the surface 2 A parallel to the light transmission direction of the substrate 2 formed by embedding the individual electrodes 3,. A common electrode 4 and an invisible eyebrow 8 are formed on the other surface 2B (II), which is parallel to one surface 2A, and a block equivalent to the previous Fis.2D is formed. 4 F. Note that the common electrode 4 is not a single electrode over the entire surface of the other surface 2 B of the substrate 2 as shown in the figure, but a plurality of electrodes corresponding to the individual electrodes 3,. In this case, the common electrode 4 is also formed by a buried electrode as in the case of the individual electrode 3 (. At this time, the unevenness on the insulating layer 9 can be almost eliminated. So Even if a low-melting glass is applied on the surface, the unevenness in thickness is reduced, and the occurrence of uneven bonding at the time of bonding to the support member side is prevented.

After the block shown in FIG. 4F is formed through the above steps, the optical shutter array 1 is manufactured through the same steps as in the case of fiS.2E—FIG.2G.

The above embodiment is an example of a preferred embodiment of the present invention, but the present invention is not limited to this embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in this embodiment, one block is configured by combining two sets of optical shutter arrays. However, the present invention is not particularly limited to this, and only one set of optical shutter arrays is used. It can also be used for shutters and the like. In this case, it is preferable that the support member 5 is arranged outside the common electrode 4 so that the common electrode 4 is sandwiched between the substrate 2 and the support member 5. As shown in Fig. 1A, it is not necessary to arrange staggered electrodes 3,…, 3 and their terminal electrodes 6,…, 6 in a staggered pattern. Placement is selected _Φ

Industrial applicability

The optical shutter array of the present invention, in which a large number of shutter elements are arranged one-dimensionally, constitutes an optical shutter by combining, for example, a polarizer and an analyzer. It can be applied to sensors, high-brightness projectors, optical switches, etc.

Claims

The scope of the claims

(1) a substrate having an electro-optical effect, a plurality of individual electrodes provided on one surface parallel to the light transmission direction of the substrate, and a plurality of individual electrodes provided on the other surface of the substrate parallel to the one surface A common electrode, a support member for sandwiching the individual electrode between the substrate, and a terminal electrode provided on the support member and individually connected to each of the individual electrodes. And a common electrode provided so as to be substantially parallel to the incident light, and a terminal electrode provided so as to be substantially orthogonal to the incident light.

(2) The two sets of the optical shutter arrays according to claim 1, wherein the optical shutter arrays are connected to each other by a common electrode via an insulating layer, and the common electrodes are connected to one common electrode terminal. An optical shutter array, comprising:

(3) a substrate having an electro-optic effect; a plurality of individual electrodes provided on one surface parallel to the light transmission direction of the substrate; and a plurality of individual electrodes provided on the other surface of the substrate parallel to the one surface. A common electrode, a first support member for sandwiching the individual electrode between the substrate and the substrate while exposing the end of the individual electrode, and exposing the end of the common electrode. A second support member that sandwiches the common electrode between the substrate and the substrate, and a plurality of individual members that are individually connected to exposed ends of the individual electrodes and that are drawn out on the first support member. An electrode terminal electrode, and one common electrode connected to the exposed end of the common electrode and drawn out on the second support member. An optical shutter array comprising: a terminal electrode for a through electrode;

(4) electrically connecting a first substrate having an electro-optic effect, a second substrate having an electro-optic effect, which is disposed in place of the first substrate, the first substrate and the second substrate; An insulating layer for separating the first substrate, a first plurality of individual electrodes provided on a surface of the second substrate opposite to a lavatory on which the second substrate is arranged, and the first substrate A first common electrode provided on a surface of the room on which the second substrate is disposed, and a first electrode provided on the surface of the second substrate opposite to the side on which the first substrate is disposed. A plurality of second individual electrodes, a second common electrode provided on a surface of the second substrate on which a first substrate is disposed, and a first plurality of individual electrodes, respectively. A first support member that sandwiches the first plurality of individual electrodes between the first substrate and the first substrate while exposing end portions of the second substrate; A second support member for sandwiching the second plurality of individual electrodes between the second substrate and the second substrate while exposing respective ends of the individual electrodes; and the first plurality of individual electrodes. A first plurality of individual electrodes and a terminal electrode which are individually connected to exposed ends of the electrodes and are drawn out on the first holding member; and individually connected to exposed ends of the second plurality of individual electrodes. And a second plurality of individual electrodes and a common terminal electrode connected to the first and second common electrodes. Features a light shutter array.

(5) The first plurality of individual electrodes and the second plurality of individual electrodes are located such that the second individual electrode is located between the first individual electrodes. The light shutter array described in 2 or 4.

(6) The individual electrode comprises an embedded electrode formed by embedding a conductive metal in a portion formed on a surface parallel to a light transmission direction of the substrate. 6. The optical shutter array according to any one of 5.

(7) The method according to any one of claims 1 to 6, wherein the individual electrodes are formed at regular intervals with a constant width, and the common electrode is formed on the entire surface of the other surface of the substrate. An optical shutter array according to any of the above.

(8) The optical shutter according to any one of claims 1 to 5, wherein the material of the substrate having the electro-optical effect is PLZT, and the material of the supporting member is ceramics. Talay

(A) a step of forming a plurality of mutually independent individual electrodes on one surface parallel to the light transmission direction of the substrate having an electro-optical effect, and a common electrode on the other surface of the substrate parallel to the one surface Forming a support member on the individual electrode of the substrate; and forming two sets of blocks formed by laminating the substrate, the individual electrode, a common electrode, and the support member. A step of forming one block by interposing an insulating material so that the common electrode faces back to back, forming a block, and a step of slicing the block on a surface orthogonal to the laminating direction; Each of the electrodes And forming a corresponding terminal electrode connected to the common electrode. A method for manufacturing an optical shutter array, comprising: (10) A plurality of portions are formed by etching on one surface parallel to the light transmission direction of the substrate, and a conductive metal is formed on this portion so that it is substantially flush with the substrate. 10. The method for manufacturing an optical shutter array according to claim 9, wherein the individual electrodes are formed by being buried.