JPH02171728A - Optical controller - Google Patents

Abstract

PURPOSE:To obtain a full control type optical device having a high S/N, and an operation characteristic of high reliability by placing the subject controller so that a signal light for passing through an optical modulation element does not pass through the surface of a circuit board, and also, a driving light for driving a photodetector is made incident from the direction being different from that of the signal light. CONSTITUTION:An optical switch element 10 having an electrooptical effect is placed so that a signal light 11 transmits through in parallel to the surface of a substrate 6, an electrode 12 is formed on both side faces of a transparent electric conductor 10 so that an electric field is applied in the direction vertical to a transmission light, and each terminal is connected to a circuit 7 for coupling each terminal of photodetectors 8, 9. In this state, when a light beam 15 is radiated to the photodetector 8 by a mercury lamp 19, a voltage generated by a bulk photoelectromotive force effect is applied to an optical shutter element 10, and by switching an optical path of a driving light 15, and switching it to the photodetector 8 or 9 which is irradiated, the signal 11 of a light beam can be controlled. In such a way, an optical switching device having a high S/N and high reliability can be obtained at a lower cost.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention uses light to transmit 4゜,
This invention relates to a device that directly controls other lights. Furthermore, for more details,
This invention relates to a light control device that can be made smaller and thinner.

[Prior Art] Conventional optical control devices are described, for example, in 27a-LJ-7 (page 80) “Prototype of all-optically controlled electro-optical device” and “EffcCt of l
l11purity Doping on Photo
striction 1nFerroelectric
Ceraa+1c-by M, Tan1 ugly ura a
nd ni Uchino, 5ensors and Ma
terials l, 46 (198g), the "electro-optic effect" in which the refractive index of a material changes depending on the applied voltage, and the effect of light (e.g. violet light) on piezoelectric crystals.
In combination with bulk photovoltaic light, which generates an electromotive force that far exceeds the band gap when irradiated with light, the light irradiation drives a light shutter through the electromotive force, and the light (red light) can be controlled. There is an all-optically controlled device that does not have a circuit. This is shown in FIG. 1, on which a slide glass is used as a substrate 6, and two light-receiving ceramic/glass elements 1 and one ceramic light shutter 2 are arranged thereon. The principle of operation is that when the light from the mercury lamp 3 hits the light receiving element 1, an electromotive force is generated, and the light metering element 2 is driven by the electromotive force.

The two driving elements A and B have mutually opposite movements M, 1! electrically connected to the optical shutter element so as to generate a pressure of 4",
When A and B are alternately irradiated with mercury lamp light, the red light of the He-Ne laser that passes through the optical sensor is modulated at 0.2 Hz as shown in Figure 2, and the S/N ratio is approximately 2 d.
It is B. The material of the light receiving element 3.4 is P L Z
T (3152/48), the material of the optical shutter 2 is P
L Z T (9/65/35) There is. Also,
The results of investigating the photovoltaic effect due to light irradiation on WO3-added P LZT show that up to 1°5 at%, the photovoltaic force increases compared to that without additives.

However, in this known device, firstly, the light-receiving f: element is cut out on top of the frame, making it impossible to make the device smaller and thinner.Secondly, lead wires are used, and the device cannot be made smaller or thinner. Third, because the red signal light (which is likely to be switched) and the driving water fM lamp light enter the device from the same direction, it is difficult to prevent the driving light from interfering with the signal light. [The need for a husband, No. 4
Since the signal light is incident in the direction that passes through the substrate,
The signal light will be affected by the substrate, that is, an opaque material cannot be used for the substrate, and a substrate with low light transmittance will lower the S/N ratio of the optical signal. There were problems such as being restricted in choices.

[Problems to be Solved by the Invention] In order to solve the above-mentioned drawbacks, the present invention provides a piezoelectric material having a bulk photovoltaic effect, such as P L Z T
(3152/48) An object of the present invention is to provide a device for controlling light using light, which drives a light modulation element using the "electro-optic effect" with the voltage generated when a light receiving element is irradiated with light. That is, the present invention eliminates the above-mentioned problems such as (1) miniaturization, difficulty in forming a single layer, (2) high assembly cost depending on the structure, and (3) restrictions on substrate material. (1) Facilitate miniaturization and thinning of layers, and allow free selection of substrate materials (Thus, (3)
): 1-stop performance, (4) S
An object of the present invention is to provide a fully controlled optical device having a high /N ratio and highly reliable operating characteristics.

[Means for Solving the Problems] The present invention provides electrodes on a transparent dielectric material having an electro-optic effect, and the polarization directions of the signal light are perpendicular to each other on the incident surface and the output surface. , and 451 to each other in the direction of the applied electric field.
A light modulation element to which two polarizers are attached so as to form a polarizer; and at least one dielectric light receiving element having a photovoltaic effect with the directions of spontaneous polarization aligned as a driving source; In a device that controls light using light, which is configured by electrically connecting elements with conductive wiring, the two types of functional elements are installed on the circuit of the circuit board, and the signal light passing through the light modulation element is This is a light control device characterized in that the drive light for driving the light receiving element is arranged so as to enter from a direction different from that of the signal light without passing through the circuit board. Then, the signal light passing through the luminous intensity subline Y- is
In order to arrange the driving light that drives the light receiving element to enter from a direction different from that of the signal light without passing through this circuit board surface, the incident surface and output surface of the signal light of the light modulating element are It is preferable that the light-receiving surface of the light-receiving element T be parallel to the circuit board. Further, the light receiving element consists of two light receiving elements r, the directions of their spontaneous polarizations are connected in series in a loop shape, and the N pole of each of the luminous intensity sub-wires T is connected to each of the above-mentioned connection circuits. It is preferable that the

The light receiving element is composed of two light receiving elements whose spontaneous polarization directions are connected in parallel in a loop shape, and each electrode of the light modulating element is connected to each of the above connection circuits. suitable.

In addition, the light-receiving element is made of piezoelectric ceramics, and PLZT (3152/3152/
48), that is, P b a, ey L a s, am (
Z r *, **T i *, am>*, ***Om
And to this, add 0 to 2°0 original Y-% of WOs,
The transparent switching element is made of LZT (3152/48), and the transparent switching element is made of lanthanum-doped zirconium lead P.
L Z T (9/65/35) ie Pb.

*IL a s, **(Z r *, *4 i *, *
A configuration consisting of *>*, *tviOs is preferred.

Regarding such a configuration, according to the present invention, a light-receiving element having a bulk photovoltaic effect is used as a driving source, PLZT having a large secondary optical effect is used as a switching element, and the direction of driving light and signal light are arranged on a circuit board. By arranging and combining these elements so that their directions do not overlap, it is possible to (1) directly control the output of other signal lights by inputting driving light without using any kind of amplifier circuit; .

(2) Miniaturization and thinning can be easily achieved.

(3) Since the signal light is incident parallel to the substrate, the material of the substrate can be freely selected, even if it is opaque.

(4) Since the material of the board can be selected, the board on which the circuit is formed can be used, simplifying the wiring process and making it possible to manufacture highly reliable optical switching devices at a lower cost. You can expect the same effect.

Historically, it has become possible to obtain a larger bulk photovoltaic effect by using PLZT doped with WO8 for the photodetector r.

The present invention is a device for controlling light using light, in which one or two light-receiving elements having bulk photovoltaic force curing are arranged in series on a substrate on which an electric circuit is formed so that the directions of their spontaneous polarizations are aligned with each other. , or an optical switch element having an electro-optical effect is connected in parallel to an electric circuit with solder or the like, and arranged so that the transmission direction of the signal light is parallel to the substrate,
A pair of electrodes provided parallel to the signal light are wired to each electrode of each light receiving element.

In addition to P LZT, which has been conventionally used as a material for the light-receiving element, we added WO3 up to 2.0% Y% to increase the bulk photovoltaic effect.
(3152/4g) was used.

Next, the present invention will be further explained with reference to the accompanying drawings.

FIG. 3 is a view of a dormitory showing an example of the device of the present invention. That is, it is an exemplary structural diagram of the optical device of the present invention, where 6 is 11
7 is an electric circuit formed on the board, and 2 is a flat board.
The light-receiving elements A and B having a bulk photovoltaic effect, ie, 8 and 9, respectively, are arranged so that the directions of their spontaneous polarizations are in series, and are connected to the above-mentioned circuit.

The optical switch element 1o having an electro-optic effect transmits a signal light 1
The electrodes 12 are formed on both sides of the transparent dielectric 10 to apply an electric field in a direction perpendicular to the transmitted light, and the electrodes 12 are arranged so that the light passes through parallel to the surface of the substrate 6. is connected to a circuit 7 that connects each terminal of the light receiving element 8.9.

In FIG. 3, the optical switch 10 further includes a signal light 11
Polarizers 13 and 14 were provided on both the entrance and exit surfaces. The polarization direction of the polarizer made an angle of 45° with the applied force direction of the electric field, and the polarizers were installed so that the polarization directions of the two polarized lights f were perpendicular to each other.

The driving light 15 is directly IK (irradiated) onto the substrate surface using, for example, a mercury lamp.

Next, FIG. 4 shows a measurement method for measuring and confirming the operating characteristics of the light control device of the present invention.
Reference numeral 16 indicates a He-Ne beam that generates the signal light 11, reference numeral 17 indicates a photodetector, and reference numeral 18 indicates a monitor, which records measurement data such as the detected light intensity. ! 9 is a mercury lamp which generates 15 driving lights. Further, the driving light 15 can be applied to one or both of the light receiving elements 8.9 or both Jj.

Next, FIG. 5 shows another example of the optical control device of the present invention, in which the optical switch element 10 is arranged outside the loop of the circuit formed by the light receiving element 8.9. Since the two light receiving elements are adjacent to each other, the light control device can be controlled without changing the control light 15 much.

Further, in FIG. 6, two light receiving elements 8.9 having a bulk electromotive force effect having a 4° angle are arranged so that their spontaneous polarization directions are parallel, and the circuits are connected. Thus, a device is obtained which can be controlled twice as fast.

[Function] The principle of operation of the optical control device of the present invention will be explained with reference to FIG. 4, which shows the measuring device.

Even if signal light is incident on the optical shutter before an electric field is applied, no output light can be obtained in principle because the polarizers are orthogonal to each other.

Next, when the light receiving element 8 is irradiated with light 15 from the mercury lamp 19, a voltage +
V is applied to the optical shutter element 10 . The signal light 11 that has received linear polarization by the polarizer 13 on the incident side passes through the optical shutter element 10 to which a voltage is applied, but at this time,
Due to the electro-optic effect, a component of the incident light 11 that can pass through the polarizer 14 on the output light side is generated, and output light is obtained.

If the state in which the initial signal light 11 is blocked is the off state, and the state in which the signal light 11 is transmitted is the on state, then the current signal can be controlled by human power using light. ! ! It will be.

Next, switch the optical path of light 15 from the mercury lamp, and
When one photodetector T-9 is irradiated, since the direction of the spontaneous polarization Ps is opposite to that of the first photodetector F8, an electromotive force -■ opposite to that when first applied is generated. Therefore, the optical shutter element -r12 in the on state is induced to be in the off state by applying the opposite voltage -V. The light signal 11 can be controlled by switching the optical path of the driving light 15 and changing the irradiating light receiving element T-8 or T-9. That is, as described above, the light, for example 15, can control other lights, for example 11, without using an electrical drive circuit.

Next, the light control device of the present invention will be explained using the following examples, but the present invention is not limited to the following examples.

[Example 1] [On control] A circuit 7 as shown in Fig. 3 was printed with silver-palladium paste on an alumina substrate of 7 x 9c.
It was formed by baking.

On the other hand, replacing the L a c′P b site of 3 primary f・%,
Z' and Ti: Zyl titanate with a ratio of 52748: 1
Pb *, *v L a *, ea (Z r *, s
41 *, as) a, s*mao n [hereinafter abbreviated as P
5111X0.31+11 of each of two tramix flat plates 8.9 with surface dimensions 20X5+w and thickness 0.3111 of composition L Z T (,3152/48)]
Apply silver paste to both sides and bake to form electrodes.
A DC electric field of 2 kV/a was applied to perform polarization treatment to obtain a light receiving element 8.9.

In addition, the Pb site was replaced with 9 at% La, and Zr and T
Titanium scale zircon scale lead where the ratio of i is 65:35, i.e. P b *, *+ L a *, a * (Z r *, s
4 i o, +a)*, 5tyiO* [hereinafter omitted, -'
r, P L Z T (9/65/35)]
M electrodes are baked on both sides of a pair of transparent ceramics 10 with dimensions of 2.5 x 2.5 x 2.5 mm, and a pair of electrodes perpendicular to this pair of electrodes and parallel to each other are mirror-finished. Polished to make it difficult for signal light to scatter.

After this mirror polishing, a positive [I-id (registered + Tfi mark) board] was attached with adhesive for polarized light of f-13 and f-14. The Bora [1 ID (registered trademark) plate was set so that the polarization direction was 45° with respect to the direction of applied electric field, and the two polarization directions were 4° perpendicular to each other. The adhesive was applied and cured to form a switching element so as not to interfere with the optical path of the signal light. The light receiving elements T-8 and T-9 were soldered in series to the circuit so that their polarization directions were antiparallel to each other. Switch Tsubaki element-P12 was arranged in the optical path of the signal light, fixed with adhesive, and electrically connected to the circuit pattern using a silver paste that hardens near room temperature.

The operating characteristics of the obtained element circuit shown in FIG. 3 were measured by the method shown in FIG. Red He-N is used as the measurement signal light.
An e-laser 16 was used. The amount of red light transmitted through the optical switch was measured with a photodetector i\17, and the data was recorded on computer 1B.

P L Z T (3152/48) Photodetector T-
A and B, ie, 8.9, were alternately irradiated with mercury lamp light for 5 seconds each, and the response characteristics of the optical switch element r-0 were measured, and the results are shown in FIG.

Also, when the driving light is irradiated on A, it is driven in the on state, and when it is irradiated on B, it is driven in the off state, and the signal light (7) S
/N ratio was 4.5 to 5 dBt'.

According to the results of the conventional technology, an S/N ratio of about 2 dB was obtained, and the S/N ratio was higher than this by 2 dB or more.

The reasons for this improvement in performance are (1) the signal light does not pass through the substrate made of glass, etc., which reduces the noise level; - Made of palladium and unnecessary length of wiring can be omitted, reducing loss of photovoltaic force due to circuit resistance. (3) Structure in which the driving light enters from the direction perpendicular to the signal light. Therefore, interference between the driving light and the signal light is extremely rare.

In addition, in this example, polarized light f・13.14 is polarized by dielectric material t=
5 Mitsu/Su PLZT (9/65/35) 101m Although it was directly attached, it is clear that the desired characteristics can be obtained even if it is installed at a distance from the dielectric Hiramix.

[Example 2] In Example 1 mentioned above, the material of the light receiving element is PL Z
T (3152/48), WO, 0.5
P L Z T (3152/48) added by atomic%
An example is shown below.

The dimensions of the light-receiving element 8.90 are the same as those of Example 1;
0.times.5.times.0.3-, and has the configuration as shown in the top view of FIG. 3, and the shape of the electrodes, polarization conditions, and configuration of the optical switch circuit are the same as in Example 1. Also,
The operating characteristics of the formed element circuit were measured in the same manner as in Example 1. The results are shown in FIG.

The obtained S/N ratio was 6-7 dB.

There was an improvement of 1.5 to 2.5 dB compared to Example 1,
This is explained in P L Z T (3152/48) by W
This is the effect of adding Os. Furthermore, the WOI is 1.0!
, 5.2. When a light-receiving element was formed using the added material with an increase to 0.2.5 at%, ! .

In the case of 0 atomic % and 1.5 atomic %, the S/N ratio is the same as the S/N ratio when using additive-free PLzT') 4>
Daifi, <, Mata, 2. OJl; (7-% addition (7)
The S/N ratio of PLZT was the same as that of PLZT with no additives, and was slightly inferior with PLZT with 2.5 JIX% added.

Therefore, the greatest effect on improving the S/N ratio was observed in the range of 0 to 2.0 atom % of WOl added.

[Embodiment 3] [Optical switch element installed outside a four-optical element circuit] As shown in FIG. A light-to-light switch element with a structure placed on the outside was fabricated.

The advantage of this structure is that since the light receiving beams f: FB, 9 are adjacent to each other, the switching width of the driving light beam 1 can be made small.

, the material of the light receiving element is W as in implementation @2.
When the materials of O, 1 & A were used, the S/N ratio was 6 dB as in Example 2.

[Example 4] [+ row polarized light receiving element - configuration] This example C uses the arrangement shown in FIG. connected to.

Its operating characteristics were measured by the method shown in FIG.
The measurement was performed by simultaneously irradiating the driving light 15 onto two light receiving elements.

The material of the light receiving element is the same as that of Example 2, and is WO,0.
, 5 atomic% addition (7) P L 'Z T (3152
/4g) -1' exists.

Started light irradiation from the drive light off state, and the transmitted light reached 6
The time to reach dB is 2 to 2.5 seconds, which is due to the drive I/f of node j, as in the case of implementation f42.
This is about 1/2 the time compared to when the driving light is irradiated.

, -, in order to detect light irradiation, it is possible to obtain more I
+4. It was confirmed that it is possible to realize a light shutter open state.

FIG. 7 is a graph showing the optical response characteristics of the optical control device of the present invention when two light receiving elements A and H polarized in opposite directions are irradiated with light at an angle t7.

FIG. 8 is a graph showing the light response characteristics of a similar light control shell of the present invention when a material containing WO1 is used.

[Effects of the Invention] According to the present invention, a light receiving element having a bulk photovoltaic effect
- is used as a driving source, and PLZT with a large secondary optical effect is used as a switching element, and these ll:f are arranged and combined on the circuit board so that the direction of the driving light and the direction of the signal light do not overlap. (1) The output of other signal lights can be directly controlled by human power of the driving light without using any amplification circuit.

(Reducing the size and thickness of the layers can be done easily.)

(3) Since the signal light is incident on the V row of the substrate, an opaque substrate can be used, and the material can be freely selected.

(4) Since the material can be selected, the board on which the circuit is formed can be
Since it can be used, the wiring process can be simplified, and a highly reliable optical switching/f device can be manufactured at a lower cost, and other effects can be expected.

Furthermore, by using PLZT doped with WOl for the light receiving element, it has become possible to obtain a larger bulk photovoltaic effect.

Historically, the light control device of the present invention has the following features: (1) ability to perform light tossing with light;
; It has been possible to provide a device that can be applied to the basic unit of an arithmetic device, etc., and is effective therein.

4. Explanation of 1fflQ'-Drawings Figure 1 is a schematic diagram of the structure of a conventional light control device.
'It is a perspective view.

Figure 2 shows the operating characteristics obtained with the conventional all-9 control type electromagnetic Igf.
) is a graph.

FIG. 3 is a plan view showing an example of a planar circuit showing the configuration of a light control device according to the present invention.

FIG. 4 is a schematic diagram f showing the configuration of another example of the light control device according to the present invention.

FIG. 5 is a schematic diagram showing the configuration of another example of the light control device according to the present invention.

FIG. 6 is a schematic diagram showing the configuration of another example of the light control device according to the present invention.

FIG. 7 is a graph showing the characteristics measured by the light control device according to the present invention.

FIG. 8 is a graph showing the measured light response characteristics by the light control device of the present invention.

Claims (5)

[Claims] (1) Electrodes are provided on a transparent dielectric material that has an "electro-optic effect," and the incident and exit surfaces of the signal light have their respective polarization directions perpendicular to each other, and the directions of the applied electric fields are at 45 degrees to each other. a light modulation element to which two polarizers are attached; as a driving source thereof, at least one dielectric light receiving element having a photovoltaic effect with the directions of spontaneous polarization aligned; That is, in a device for controlling light by light, which is configured by placing two types of functional elements, a light modulating element and a light receiving element, on one circuit board, the two types of functional elements are mounted on one circuit board. installed on an optical path, and arranged so that signal light passing through the light modulation element does not pass through the circuit board surface, and driving light for driving the light receiving element enters from a direction different from that of the signal light. A light control device characterized by: (2) Since the signal light passing through the light modulation element does not pass through the circuit board surface, and the driving light for driving the light receiving element is arranged so as to enter from a direction different from that of the signal light, Claim 1, wherein an incident surface and an output surface of the signal light of the light modulation element are perpendicular to the circuit board surface, and the light receiving surface of the light receiving element is average with the circuit board. The light control device described in Section 1. (3) The light receiving element is composed of two light receiving elements, the directions of their spontaneous polarizations are connected in series in a loop, and each electrode of the light modulating element is connected to each of the connection circuits. The light control device according to claim 1, characterized in that: (4) The light-receiving element is composed of two light-receiving elements, whose spontaneous polarization directions are connected in parallel in a loop, and each electrode of the light modulation element is connected to each of the connection circuits. The light control device according to claim 1, characterized in that: (5) The light-receiving element is a piezoelectric ceramic body, made of lanthanum-doped lead zirconate titanate having a bulk photovoltaic effect, and containing 3 mol% of La, PLZT (3/52/4
8), that is, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Sintered body and PLZT with 0 to 2.0 atomic % of W O_2 added to it (3/52
/48) A transparent switching element made of a sintered body is
Lanthanum-added lead zirconate titanate: PL2T (9/6
5/35) That is, ▲There are mathematical formulas, chemical formulas, tables, etc.▼The light control device according to claim 1, which is made of a sintered body.