JPS63101817A - Optical shutter array element - Google Patents

Abstract

PURPOSE:To facilitate the process for prepn. by providing an optical shutter part consisting of projecting parts of plate bodies enclosed by 1st, 2nd and 3rd grooves and satisfying the conditions a>c>b (a, b, c are the depth of the 1st, 2nd and 3rd grooves). CONSTITUTION:The many grooves 6, 6 for element sepn. are formed to PLZT2, which is deposited with aluminum by evaporation over the entire working surface, machining by using a dicing saw over the entire length at the specified pitch in the Y-axis direction intersecting orthogonally with the X-axis direction. The width of the grooves 6 is 20mum and the depth (c) satisfies the condition a>c>b. More specifically, the control electrode and electrode lead parts of the respective shutter elements can be separated and formed by cutting off part of the vapor deposited aluminum films of the grooves 4, 5 if the depth (c) of the grooves 6 is set in the above-mentioned manner with respect to the groove 3, and the grooves 4, 5. On the other hand, the need for cutting off the base part of the vapor deposited aluminum film of the groove 3 is eliminated and the electrode having nearly the same shape as the shape of control electrodes are formable simultaneously with the formation of the planar common electrode.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical shutter using a substance having an electro-optic effect, and particularly to an optical shutter array element that is expected to be used in optical application equipment.

Substances that have an electro-optic effect, especially PL with a large force constant
A plurality of optical shutter elements are arranged one-dimensionally using ZT to form an optical shutter array element, and an optical shutter is constructed by combining this with a polarizer and an analyzer. Such an optical shutter has a fast response speed and is expected to be applied to high-speed printers, especially electrophotographic printers.

Conventionally, this type of optical shutter 7-ray element uses a wafer-shaped P
It was constructed by forming an electrode pattern on the surface of LZT (planar electrode type), but due to drawbacks such as the presence of stray capacitance and high driving voltage, recently the shutter element has been formed into a rectangular solid shape. A so-called parallel electrode type structure in which electrodes are formed on opposing surfaces is disclosed in, for example, Japanese Patent Application Laid-Open No. 60-15972.
This method has been proposed in Publication No. 2, Japanese Patent Application Laid-open No. 170828/1983, and the like.

The technique disclosed in Japanese Patent Application Laid-Open No. 60-159722 involves adhering rod-shaped PLZT on which a counter electrode is formed onto a glass substrate on which electrodes for a connection layer have been patterned in advance, and cutting the rod-shaped PLZT at a constant pitch using a diamond cutter. This is an optical shutter array element.

Another technique disclosed in JP-A-60-170828 is
7 Otolithography technology is used, and a flat P
Chemically etching the LZT to form a groove for the electrode placement part,
Next, a metal for electrodes is deposited on the entire surface, and then a predetermined 1!
The optical shutter 7-ray element is completed through an etching process using the 7-lithography technique again so as to form a polar pattern and structure.

However, the former technique described above has the problem of an extremely complicated manufacturing process.On the other hand, the latter technology also has a complicated manufacturing process and groove formation is done by chemical etching, so this method is difficult to achieve. The depth of the groove cannot be increased (approximately 2μ in the example).
theory), there is a problem in which it is difficult to reduce the voltage from the viewpoint of driving the shutter element.

[-1 for g to γ] An object of the present invention is to provide an optical shutter array element that can easily reduce the voltage for driving the shutter and is extremely easy to manufacture.

The optical shutter array element according to the present invention includes a first groove provided along the longitudinal direction of an elongated plate-like body having an electro-optic effect and having a single electrode metal film on the bottom and side surfaces;
A second groove is provided at a predetermined distance from the first groove along the first groove, and has a metal thin film for electrodes intermittently on the bottom and side surfaces; A large number of third grooves are provided at a pitch of . Second. and an optical shutter section consisting of a protrusion of a plate-like body surrounded by a third groove, and is characterized in that it satisfies the following conditions.

a>c>b However, agbHc is the first . Second. This is the depth of the third groove.

Said 1st. By making the depths of the second and third grooves a>c>b, when forming the third groove, the metal thin film for the electrode provided in the #41 groove is shared by each shutter part. In this state, it becomes possible to connect the metal thin film for the electrode provided in the second groove by 1tli for each shutter portion. This greatly simplifies the manufacturing process.

XBlood Dish The following will specifically explain the embodiments shown in the accompanying drawings.

FIG. 4 shows an example of an optical shutter array element. The optical shutter array element (10) has a rectangular parallelepiped optical shutter section (11), (11), .
11^), an optical shutter section (12) having the same shape as the optical shutter section (11), and an element array (12) of (12)=...
(13) is a common electrode provided to span the element array (118) and the element array (128), and (14) is an optical shutter section (
The control electrode (11) has a lead part (14N) for connecting to an external drive circuit, and the control electrode (15) of the optical shutter 1 (12) similarly has a lead part (14N) for connecting to an external drive circuit. 15N).

Groove (3) provided with common electrodes (13), (13)
), the groove (
4), (5) and a number of grooves (6), (6) commonly separating each element of the element array (IIA), <12^).
t... are all formed by cutting. The manufacturing process of this optical shutter array element (10) will be explained with reference to FIGS. 1 to 4.

As shown in Figure 1(,), a long plate-shaped PLZT (1
) to prepare. Both the front and back surfaces of PLZT (1) have been optically polished in advance. For example, PLZT (1) has a composition of 9/65
/35, its shape is 100a+m long and 5m wide.
m5 thickness is 0.5 mm.

tPJ1 As shown in Figure (b), a band-shaped resist pattern (2) is formed approximately at the center of the surface of this PLZT (1). The width of the Lennost pattern (2) was set to 300 μm, and a general photolithography technique was used. This resist pattern (2) is, as described later,
Used to remove deposited metal. Note that the longitudinal direction of PLZT (1) is the X-axis direction, and the direction perpendicular to the X-axis direction in the first direction is the Y-axis direction, and a cross-sectional view taken along the line ■-■ is shown in FIG. The thickness of the resist pattern (2) may be about 1 μm.

Next, the PLZT on which this resist pattern (2) was formed is
The center of the M resist pattern (2) of (1) is cut along the entire length of the PLZT (1) in the X-axis direction to form m (3) for the common electrode shown in FIG. Cutting was performed with a guissing tool with a feed accuracy of 5 μm, and a diamond cutter with a blade thickness of 25 μm was used.

! The shape of (3) has a width of 80 μW and a depth of a=150 μ.

Note that the depth is based on the surface of PLZT (1).

Furthermore, in the same manner as the cutting process described above, the PLZT (1) is cut over the entire length in parallel to the groove (3) at a constant interval from both side edges of the groove (3), that is, in the X-axis direction. As shown in Figure 3, the groove (4) for the 7-ray element, the groove (
5) are formed in order. The grooves (4) and (5) have the same shape, '@80μ theory, and depth b=tiop-.

The distance between groove (3) and grooves (4) and (5), that is, the length of the shutter window of the optical shutter section was set to 80 μm. In addition, the length of this shirt window is 80AIIIl and! (3L groove (4) (
The depths a and b in 5) can be freely selected depending on the performance required of the optical shutter and within the range of cutting accuracy. However, the condition is a>b.

The next step is to provide conductive metal for the electrodes.

In the example, PL was cut using a sputtering method.
Aluminum was deposited on the entire surface of ZT (1) including the processed surface.

Next, PLZT (1) with this aluminum vapor-deposited over the entire processed surface.
Then, using a cutting tool, cutting was performed over the entire length at a constant pitch in the Y-axis direction perpendicular to the X-axis direction, and the fourth
As shown in the figure, there are many grooves (6), (6L) for element isolation.
... to form. The blade thickness of the diamond cutter is 15
A micrometer was used. ! (6) width is 20μ, depth c
=130 μm1 The pitch was 80 μm. The depth C is
The condition a>c>b is satisfied. That is, groove (3), groove (4
) If the depth C of the groove (6) is set in this manner for (5), part of the aluminum vapor deposited film of m(4) and (5) is scraped off to form the control electrode and electrode lead portion of each shutter element. While it can be formed separately, it is not necessary to scrape off the bottom part of the aluminum vapor deposited film in the groove (3), and at the same time a planar common electrode can be formed and a counter electrode having substantially the same shape as the control electrode can be formed. Compared to the conventional example in which electrode formation required a very complicated process, this example requires only a simple grooving process, and the process for electrode formation is greatly simplified.

Finally, the aluminum vapor deposition film formed on the upper surface of the shutter element (11), <12) is removed. The aluminum vapor deposited film is formed on the renost (2), and the resist (2) is removed together with the aluminum vapor deposited film using a resist stripping solution (
In addition, the method for removing the deposited film is the method using a resist, or the method equivalent to optical polishing, which does not use a resist (omission of the resist forming step) and directly deposits a metal thin film on the PLZT surface. It is also possible to scrape it off using the method described below.

In the manner described above, the optical shutter 7-ray element (10) shown in FIG. 4 is obtained. The optical shutter array element (10) is
A cable 7-ray (11A) consisting of an optical shutter section (11), (11), ... and an optical shutter section (12), (12)
, . . . consists of two rows of 7 arrays (128) of elements. FIG. 5 shows an equivalent circuit diagram. In the figure, (20)
is a drive circuit (including a circuit in the form of a semiconductor chip) that provides a drive pulse to the shutter element (11) of the element array (11^), and (21) is the shutter element (12^) of the element array (12^).
12).

The drive circuit (20) and the element array (11^) are individually electrically connected to the odd-numbered optical shutter sections (11) of the element array (11^) via lead wires, and the drive circuit ( 21) and element array (12^) are element array (1
Similarly to the even-numbered optical shutter sections (12) in item 28), they are individually connected via lead wires. Drive circuit (20), (21
) is not used. The drive circuits (20) and (21) are created in a time-division manner, and the shutter action of the two rows of shutters 7 rays (IIA) and (12^) produces a dot-shaped image. The zero time difference for forming one line is adjusted by rotating the image forming unit, for example, the photosensitive drum.

As a result, a high resolution of 80 μm transfer pitch, that is, 12 dots/lII+1, can be achieved with the optical shutter of the embodiment.

As shown in the above embodiment, two shirt rows are provided.

The reason for this is to avoid the difficulty of connecting lead wires between the optical shutter array element and the drive circuit so that this high resolution can be achieved. That is, the shutter element (
As shown in the partial plan enlarged view of the electrode lead part (15β) connected to the control electrode in 12), the electrode lead part (15N) has a pitch of 80 μm and a width of only 60 μm.
The current lead wire bongoo has a pitch of 80μ-
It is difficult to find a device with such accuracy that sufficient connection strength can be obtained with an average connection diameter of 60 μm or less.

Therefore, in order to suit the current state of wire bongs, the electrode lead parts (151) and (14Z) are connected to the lead wires every other electrode, that is, at a pitch of 160 μm. Therefore, in this way, it becomes possible to easily put it on an automated line, and there is a great benefit in terms of productivity.

FIG. 7 shows another embodiment with two shirt shirt rows.

This is an improved version of the optical shutter array element (10) shown in FIG. 4 from the viewpoint of lead wire connection.

That is, the optical shutter parts (11') and (1
The ends of the electrode lead parts (141) and (151) of 2') are scraped off to form deleted parts (34) and (35), and the electrode lead parts (141) and 2' of the optical shutter part to be operated are cut off to form deleted parts (34) and (35).
When connecting the lead wire to the end of the 151) by hanging, etc., the removed parts (34) and (35) allow the connection and α (average diameter of 100 μm or more is required to ensure connection strength) to be connected to the adjacent electrode lead. This effectively prevents the device from being connected to other parts. Note that the deleted portions (34) and (35) can also be formed using a diamond cutter in the same manner as the groove processing.

In addition, instead of such cutting, in the example shown in Figure tlIJ4, even if the connection point part is connected to the adjacent electrode lead part, there will be no problem in the actual operation of the shutter. The shutter window of the element may be masked in advance~1° In both of the above embodiments, two rows of shutter shutters are provided in consideration of connection with an external drive circuit. If there is no need to pay special attention to this connection, or if there is a separate precision connection technology, basically the method shown in Figures 8(a) and (b)
It goes without saying that these embodiments may also have one row of shirts as shown in FIG. All the optical shutter sections may be made operable, or every other optical shutter section may be made operable.

Cutting can be performed within the range allowed by the accuracy of the cutter without being limited to the dimensions and shapes of the embodiments shown above. Further, if the groove is made deeper, the driving voltage can be lowered, and even if the width of the shutter window is made larger, the driving voltage can be lowered.

In addition, FIG. 8(a) is an example in which the groove (6) is provided up to the groove (3), and FIG. 8(b) is an example in which the groove (6) is cut all the way in the width direction of the PLZT (1). Although the latter is superior in terms of ease of processing, the former has an advantage in electrical characteristics because the common electrode (13) that provides a base bias has a large area.

In addition, in the above embodiment, the lead part (14F), (1
51) is for connecting the lead wire, and does not need to protrude from the bottom of the grooves (4) and (5), but should be flush with the bottom of the grooves (4) and (5). It may be provided inside.

As mentioned above, according to the present invention, there is no crosstalk,
An optical shutter array element that can be driven at a low voltage can be obtained substantially only by grooving, and the manufacturing process can be made extremely simple.

[Brief explanation of the drawing]

1(a), (b), FIG. 2, FIG. 3, and FIG. 4 are explanatory diagrams of the manufacturing process of an optical shutter array element according to an embodiment of the present invention, and in particular, FIG. FIG. 5 is an equivalent circuit diagram showing the connection with the motion circuit, FIG. 6 is a partially enlarged plan view of the electrode lead part, and FIG. Figure 8 (a), (b)
) is a diagram showing an example in which the number of shirt shirt rows is one. 1... PLZT, 3... Groove for common electrode, 4, 5...
...Groove for control electrode, 6...Groove for element isolation, 11.
12... Optical shutter section, 13... Common electrode, 14.
15...Control electrode.

Claims (1)

[Claims] (1) A first groove provided along the longitudinal direction of a long plate-like body having an electro-optic effect and having a metal thin film for electrodes on the bottom and side surfaces; A second groove is provided at a predetermined distance from the first groove and has a metal thin film for electrodes intermittently on the bottom and side surfaces, and a large number of third grooves are provided at a predetermined pitch in the width direction of the plate-shaped body. An optical shutter array element comprising: a groove; and an optical shutter section consisting of a protrusion of a plate-shaped body surrounded by the first, second, and third grooves, and satisfying the following conditions. a>c>b where a, b, and c are the depths of the first, second, and third structures.