JPS59135438A - Optical element - Google Patents

Abstract

PURPOSE:To enable image display with high resolution by providing heating elements for heating a part of the core layer in an optical waveguide and generating vapor bubble in the liquid in the core layer. CONSTITUTION:If a switch 5b for heating electrically the heating resistor 4b among heating resistors 4a, 4b... provided like a dotted line is turned on, the part of a clad layer 2 and a part of a core layer 1 are thermally conducted and heated to boil, and a bubble 6 is formed in the layer 1. Light is refracted on the surface of the bubble 6 and is thus scattered. As a result, the course of the light, which arrives at the bubble 6, of light 7, is disturbed and since the condition of total reflection is consequently broken, a part of the light arriving at the bubble 6 passes the layer 3 and emerges to the outside of the optical element as exit light 8. An observer 12 senses visually the light 8 as if said light is emitted from the resistor 4b.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical element used for display, an optical device using the same, and a method of operating the same.

Currently, cathode ray tubes (so-called CRTs) are widely used as terminal displays in various office equipment and measuring instruments, or as displays in monitors for televisions and video cameras.

However, dissatisfaction remains with this CRT in that its image quality, resolution, and display capacity do not reach the level of hard copies made using silver halide or electrophotography.

In addition, as an alternative to CRT, attempts have been made to commercialize so-called liquid crystal panels that display liquid crystals in a dot matrix, but these liquid crystal panels also have problems with driveability, display performance,
We have not been able to obtain anything that is completely satisfactory in terms of reliability, productivity, and durability. Furthermore, optical shutters that utilize liquid crystal light valves are attracting attention as optical path modulating elements.

However, the drawback of the above-mentioned mounting device is that it requires a complicated and expensive optical system.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an optical element that overcomes the above-mentioned difficulties in the prior art and can realize a simple light modulation device or display device without using a complicated and expensive optical system, an optical device using the same, and an optical device using the same. VC is to provide a method of operation.

Furthermore, another object of the present invention is to provide an optical element that eliminates the need for a complicated and expensive optical system and has excellent driveability, reliability, productivity, durability, etc., an optical device using the same, and an optical device using the same. There is a need to provide an operating method.

Still another object of the present invention is to provide an optical element capable of producing high-resolution, high-quality images, an optical device using the same, and a method for operating the same.

Embodiments of the present invention will be described in detail below with reference to the drawings.

Figures 1 to 3 are basic configuration diagrams showing the basic principle of the optical element according to the present invention.

FIG. 1 is a partially schematic vertical cross-sectional view of an optical element according to the present invention, and FIG. 2(a) is an optical element having a cross section as shown in FIG. 1, cut along the line A'-A''. 1 and 2 ( ), / is a liquid having a relatively higher refractive index than the refractive index of the cladding layers 2 and 3; This layer forms an optical waveguide and is called the core layer because it functions similarly to the core of an optical fiber.

Further, the thickness of the core layer is preferably within the range of /μm to /thigh. ! , 3 are cladding layers corresponding to the cladding of the optical fiber, which cover the core layer from above and below. surface,
This clad layer! , 3 is a ratio higher than the refractive index of the core layer in order to propagate and concentrate light within the core layer using total reflection of light at the interface with the core layer.

A transparent member having a relatively low refractive index, such as low refractive index glass or low refractive index plastic, is used. ,(
However, the cladding layer 2 may be opaque. ). Next, a heating element for heating the core layer to an extent that partially generates steam bubbles is disposed on at least one of the two rad layers. In this embodiment, It is disposed in contact with the outside of the cladding layer.

Further, this exothermic ammonium oxide may be disposed close to the outside of the cladding layer. Further, the heat generating elements are disposed on the entire outer surface of the cladding layer or in a segmented manner such as dots, islands, dotted lines, or dotted rows.

In the case of this embodiment, as shown in FIGS. 1 and 3(a), the heating element y has one end connected to the ground side and the other end connected to each electrode (not shown). Heating resistor gummies 1gb... are attached to the cladding layer λ in a dotted line pattern. 5(ja%tb...
...) are switches, one end of each is connected to a common power supply voltage, and the other end of each is connected to the heating resistor '%
a, Fb, . . . are connected to unillustrated electrodes. B is the core layer/vapor bubbles formed inside (
Hereinafter, this will be referred to as a bubble. ), for example, switch jb
By turning on, the heating resistor 9b is heated by electricity, and this heat is transferred to the core layer through the cladding layer 2, causing the core layer to boil and form bubbles. .

7 is light in the visible region that enters the core layer and propagates within the core layer; 7 is the emitted light that is emitted from the core layer through the cladding layer 3; and 2 is the observer.

Next, the operating principle, which is the basic light modulation principle and display principle of the optical element according to the present invention, will be explained with reference to FIGS. 1(a) and 2(,). When the core layer/ is unheated and its refractive index is uniform, light is applied to the unheated core layer/ which has a relatively high refractive index covered by a cladding layer having a relatively low refractive index. When light 7 is incident, the light 7 is totally reflected at the interface between the core layer and the cladding layer or 3, so the light 7 is totally reflected at these interfaces and propagates inside the core layer. Proceeding to the other end is known from the principles of optical fibers (also referred to as optical waveguides) and thin film optical waveguides. At this time, if there is a leakage of the light 7 to the observer separated by the cladding layer 3, a small amount of light will reach the viewer as emitted light, but the light 7 does not actually reach the viewer.

Now, a switch turns on Sb as shown in FIG. 1 in order to heat the heating resistor g'ytb of the heating resistors &a%gb arranged in the form of a dotted line. Due to this electrical heating,
The part of the cladding layer near the heating resistor gb and the core layer/
The part is heated by thermal conduction and boils, forming a bubble 6 in the core layer.The light 7 is refracted, reflected, and scattered on the surface of this nozzle.

As a result, the path of the light that has reached this bubble B out of the light 7 is disturbed, and the condition of total internal reflection is therefore broken, so that at least a part of this light that has reached the bubble 6 no longer exists in the core layer/
The light passes through the cladding layer 3 and exits the optical element as emitted light g without propagating inside the optical element. At this time, the observer/! appears as if the emitted light K were emitted from the heating resistor 41b. Note that if an optical sensor is placed in place of the observer/2, the optical sensor will detect this emitted light g.

In this case, if the heating resistors 'aa, 9b... are minute dots, the bubbles formed by heating the heating resistors 'aa, 9b, etc. with electricity are also minute. becomes. The course of the light 7 is disturbed by this minute bubble 6VC, and a part of the light 7 emerges from the optical element as emitted light g.
Observer/2 perceives the heating resistors Ga, Fb, . . . as if they were emitting point light. On the contrary, if the heating resistor g a111tb... has an arbitrary shape with a certain size, the observer/2 will recognize it as having such a shape displayed. do.

In addition, if the minute heating resistors in the form of dots are arranged in a dotted row, some of these heating resistors are heated with electricity, so that the heating resistors heated with electricity are heated. The shape created by the point set of bubbles formed by the body allows the viewer to recognize various characters and images.

Note that instead of one bubble B as shown in FIG. 1(a), a plurality of bubbles may be formed as shown as K bubble B' in FIG. in this case,
Since the path of the light 7 is more widely disturbed by the plurality of bubbles A', the aperture of the emitted light becomes wider.

Further, as the basic composition of the translucent liquid as the material of the core layer, water or various organic solvents may be used alone or in combination. Examples of various organic solvents used here include methyl alcohol, ethyl alcohol, n-propyl alcohol, isoflobil alcohol, n-butyl alcohol, se'c-butyl alcohol, tert,
Alkyl alcohols such as 7'-tyl alcohol, isobutyl alcohol, pentyl alcohol, hekynyl alcohol, heftyl alcohol, octyl alcohol, nonyl alcohol, tesyl alcohol; hydrocarbons such as hexane, octane, cyclopentane, benzene, toluene, gycylol, etc. Solvents: For example, halogenated hydrocarbon solvents such as carbon tetrachloride, -trichloroethylene, tetrachloroethylene, tetrachloroethane, dichlorobenzene; For example, ethers such as ethyl ether, butyl ether, ethylene glycol diethyl ether, ethylene glycol monoethyl ether, etc. Solvents: For example, ketone solvents such as acetone, methyl ethyl ketone, methyl amyl ketone, methyl amyl ketone, and cyclohexanone; Alcohol solvents such as diacetone alcohol; Amides such as dimethylformamide and dimethylacetamide; Amines such as triethanolamine and diethanolamine; Polyalkylene glycols such as polyethylene glycol and polypropylene glycol; Ethylene glycol, Flopylene glycol, butylene glycol, hexylene glycol, alkylene glycols;
Examples include polyhydric alcohols such as glycerin; petroleum hydrocarbon solvents, and the like.

In addition, it is an essential condition that the refractive index of the translucent liquid constituting the core layer is higher than that of the cladding layer, 2.3, and the refractive index of the cladding layer β,3 is usually /S. Therefore, seven specific examples of liquids that satisfy the refractive index conditions are listed below from among the above-mentioned liquids.

The above is just an example, and it goes without saying that the liquid constituting the core layer according to the present invention is not limited to the above liquid.

FIG. 3 shows a schematic cross section of another embodiment of the optical element shown in FIG. 1, in which a light diffusing layer 2 is provided adjacent to the top of the cladding layer 3.

In FIG. 1 and FIG. β(a), as mentioned above, the observer sees that at least part of the light 7 whose path is disturbed by the bubble B, that is, the light that has passed through the cladding layer 3. However, since this emitted light has some directionality depending on the shape of the bubble, the viewing angle at which this emitted light can be seen is limited. Therefore,
If the light diffusion layer 2 is provided on the cladding layer 3 as shown in Fig. 3, the light passing through the cladding layer 3 will be scattered by this light diffusion layer, so this scattered light cannot be seen visually. The viewing angle is extremely wide, which is favorable for the observer.

In addition, in the above-mentioned 11 embodiments, the heat generating element is not limited to being installed outside the cladding layer, but the heat generating element may be installed outside the cladding layer as long as the above object of the present invention is met. It may be provided internally or inscribed.

Further, the cross-sectional shape of the core layer/and cladding layer 2.3 along the line A'-A'' of the optical element shown in FIG. 1 is shown in FIG.
), but as shown in Figure 2(b), there is also a core layer with a circular cross-section; in this case, the cladding layer! , 3 are integrated into a tubular Tsuclad layer! (referred to as an optical waveguide).As mentioned above, the general cross-sectional shape of the core layer/3.3 is a circle as shown in Figure 3. Although the present invention is not limited to these shapes, the present invention is not limited to these shapes. Figure 9 shows the basic configuration of an optical element according to the present invention that uses an infrared absorbing layer as a heat generating element. FIG. 2 is a partially schematic longitudinal cross-sectional view of one embodiment of the invention.

In FIG. 9, / is a core layer made of the above liquid, -2,
3 is a cladding layer covering this core layer; 7 is light in the visible range that enters this core layer and propagates inside the core layer;
In the figure, the light 7 is one emitted light that is emitted to the outside through the cladding layer 3, and /2 is the observer.

Note that the refractive index of the liquid in the core layer is that of the cladding layer! , 3 is relatively higher than the refractive index of the members. Reference numeral 10 denotes an infrared absorbing layer as a heat generating element, which is provided on the entire outer surface of the cladding layer λ. B is a bubble formed inside the core layer when the liquid in the core layer boils, and the infrared absorbing layer θ is irradiated with infrared rays, and the irradiated part of the infrared absorbing layer θ generates heat. This heat is transmitted to a portion of the core layer via the cladding layer 2, and the core layer is locally heated and boiled, forming bubbles.

Next, with reference to FIG. 9, the operating principle that is the basic light modulation principle and display principle of the optical element according to the present invention will be explained.

When the infrared rays // are not irradiated to the infrared absorbing layer /θ, and therefore the core layer / is not heated and its refractive index is uniform, the light 7 incident on the core layer / is transmitted to the core layer / and the cladding layer. layer 2
Or, it propagates within the core layer while being totally reflected at the interface with 3. At this time, the light 7 passes through the cladding layer 3 to the observer/
2 and is orange, so when observer/2 looks at this optical element, he cannot see any light.

7 Now, when the infrared absorbing layer /θ is irradiated with infrared rays // as shown in the figure, the infrared absorbing layer /θ in the irradiated area generates heat. This heat is transferred to the core layer through the cladding layer 2, and the core layer is heated to the extent that boiling occurs to form the bulb B. A part of the light 7 is scattered, refracted, and reflected by the surface of this bubble B. As a result, light 7
The path of the light that has reached this bubble B is disturbed, and the condition of total reflection between the core layer and cladding layer 3 is broken, and at least a part of this light does not propagate inside the core layer and is transferred to the cladding layer. 3 to the outside of the optical element as an emitted light -1
It is ejected and reaches the observer/=2.

At this time, the observer /, :2VC sees the emitted light as if it were emitted from the infrared absorbing layer /θ of the heat generating area. Note that if an optical sensor is placed in place of the observer, the emitted light enters the light receiving surface of the optical sensor (not shown) and the light can be detected. Also, the cladding layer λ or the crand layer of the optical element having the configuration shown in FIGS. 1 to y! If the heat-generating element is transparent, a part of the light 7 that reaches this part of the bulb 6 or 6' will be connected to the cladding layer 2 or the cladding layer--although not shown in the figure. There is also some exit light that passes through the element.

Therefore, in this case, the emitted light can be observed from both sides of the optical element.

Note that the bubbles formed in the core layer of the optical element having the configurations shown in FIGS. 1 to 9 will disappear if the heat supply is cut off and the bubbles are cooled (whether by natural cooling or forced cooling). Therefore, all the light 7 that reaches this part returns to the core layer/
It is totally reflected at the interface between the core layer and the cladding layer and propagates within the core layer.

Note that in the embodiments of the optical element having the configurations shown in FIGS. 1 to 9, the heating element is not limited to being installed outside the cladding layer, and it can be used to meet the above objectives of the present invention. In a limited case, the heating element may be provided inside the cladding layer or inscribed on the core layer side, or a combination thereof may be used. The same applies to the case of the mirror described later◇In addition, a mirror with a light-reflecting metal film coated on the substrate may be used instead of the cladding layer 20 of the optical element having the configuration shown in FIGS. 1 to 9. Good too. However, in this case, it is clear that the mirror surface may be placed in contact with or close to the core layer.

FIG. S is a partially fragmented schematic perspective view of an embodiment of a display device to which the optical path modulation principle of the optical waveguide shown in FIGS. 1 and 2(b) is applied.

In FIG.
.../9k (hereinafter referred to as heating resistor, l).

) is provided. A large number of optical waveguides each having a core layer and a cladding layer whose longitudinal direction is perpendicular to these heating resistors and whose vertical and horizontal cross sections are shown in FIG. 1 and FIG. 2(b). / , S a, /jb, /jC...
... /jn' (hereinafter referred to as optical waveguide /S) is arranged on the heating resistor /g. Reference numeral 72'' indicates a laser beam having a wavelength in the visible region, which is repeatedly scanned in the direction of the arrow shown in the figure and sequentially enters one of the core layers of the optical waveguide/S. It shows a display element made up of constituent elements. Also, /5'a, /j7
A is a bubble formed by heating the core layer of the optical waveguide/ja to such an extent that boiling occurs.

However, bubbles formed in other optical waveguides are not shown.

Now, when the heating resistor/G is not heated by electricity, the core layer of the optical waveguide/S is not heated, so the first
The bubbles described above in the figure occur in the core layer of the optical waveguide /j. Therefore, the laser beam /2'' incident on the core layer of the selected optical waveguide in the optical waveguide /S is totally reflected by the core layer and cladding layer described above in Fig. 1, while the optical waveguide propagates inside. and eject from the other end.

Next, only the heating resistors /1ltc and /4tk are heated by electricity, and at this time, when the laser beam 72'' enters the optical waveguide /ja, the heating resistors i'4' c , / ¥
By heating with electric current of k, bubbles (in the optical waveguide/Sa, /j'a%/j'a ) is formed. On the other hand, the beam /2'' entering the optical waveguide /ja has its course disturbed by both bubbles /3'a, , A5'a as described in the explanation of Fig. 1, and some of the beam The light passes through the cladding layer of the optical waveguide/ja and is emitted to the outside of the display element/b as display light, as indicated by the arrow in the figure.

Next, an appropriate number of heating resistors/da are heated by electricity, and a laser beam/, 2'' is made incident on the optical waveguide/5.b to display the optical waveguide y isb. /, Sc....../3n is repeated to display the display element /B two-dimensionally as one screen. Note that the bubble formed in the core layer of the optical waveguide /j, for example, the optical waveguide Wave tube /ja core layer formed bubble 15'a, /
Other optical waveguides formed together with 3'a, such as optical waveguide/5bVc, are cooled naturally when the laser beam/-2'' enters optical waveguide/sb for the next display. Or, regardless of forced cooling, it will cool and disappear and return to its original state, so the next optical waveguide /
There is no problem when displaying jb. That is, when the next optical waveguide /jb is displayed, the heating resistor /41c, /'lk
If you want to display the corresponding points above, use the heating resistor /fc again.
It is sufficient to conduct heating by applying current to /4k, and if there is no need for display, heating by applying current to /Zc and /llk is not necessary.

FIG. 6 is a schematic structural perspective view of an embodiment of a display device in which the display element shown in FIG. 5 is provided with a light source of a light emitting diode element array.

In FIG. 6, like the components in FIG. 5, /3 is a substrate /g is a heating resistor, /j is an optical waveguide, and light-emitting diodes /7a, /7b, /7c are on the incident surface side.・・・・・・
The flat plate microlens array / is arranged so that the light beam emitted from the light emitting diode array /7 consisting of /7n efficiently enters each of the corresponding optical waveguides 7.5' (However, This flat microlens array is not necessarily necessary; each light emitting diode /7IL, /7b, /7c.../7n is a respective optical waveguide /!; a, /3 b, /3 c-
/l'n K corresponds to each / item.

The display operation in the case of FIG. 6 is exactly the same as in the case of FIG. A bubble is formed in the core layer of optical waveguide/j, and the light emitting diodes of light emitting diode element array/7 corresponding to one of the corresponding leading waveguides/j to be displayed emit light, and the light is transferred to the corresponding optical waveguide. Inject it into the tube.

Thereby, the display is performed by the bubble of the predetermined optical waveguide on the same principle as the display principle explained in FIGS. 1 and 5. Light emitting diode element row/7 light emitting diodes/
7a, /7b, /7c, . . . , /7n are emitted and scanned one after another, and the display element /B is displayed as seven screens in a ρ-dimensional manner.

However, in the configuration shown in Figure 4, a similar display can also be achieved by sequentially heating the heating resistors and making any plurality of light emitting diodes emit light in synchronization with the heating signal. be.

FIG. 7 is a partially exploded schematic perspective view of an embodiment of another display device using the optical element shown in FIG. 1. FIG.

In Figure 7, 1. ．． Reference numeral 2.2 is a light-transmissive cladding layer made of a plate-shaped member with a relatively low refractive index, and is provided with a large number of grooves in a striped pattern. , 2 is a cladding layer composed of a thin plate-like member with a relatively low refractive index. It is integrated with. As a result, the grooves in the cladding layers 72, 2 are hollowed out by the cladding layer βB and become elongated hollow holes. The large number of parallel, elongated cavities are filled with the liquid having a relatively high refractive index and serving as the core layer. These allow a large number of parallel optical waveguide holes, 2ja, , 2jb1 . ．．
23 c −, 25n (hereinafter referred to as optical waveguide hole, 2j)
is formed.

These cladding layers, 2, 2. ．． 2 Otsu and optical waveguide hole, 25
These are collectively called optical waveguide panels. 73' is a substrate, on which a large number of heating resistors 23a, 23b are arranged in stripes.
, 23c..., 23k (hereinafter referred to as heating resistor-3) are provided. This heating resistor, 23
The optical waveguide hole 2j is provided perpendicularly above.

Create such an optical waveguide panel. Still another effective means is a heating resistor disposed on the substrate 73';
A cladding layer coated with a low refractive index dielectric such as K 5iOz on 23! There is also a method of forming a groove and then bonding the substrate 73' and the cladding layer in which the groove is formed.

, 27 is a light diffusing layer provided on the cladding layer 2.2, for example, the upper surface of the cladding layer 2.2 has a finely uneven shape. The cross section of this optical waveguide hole 2j along the longitudinal direction is exactly the same as the cross section shown in FIG. The display element 2/ is constituted by these above-mentioned components. A light emitting diode /soa, /? b.

/9 c-/Light emitting diode element array consisting of 9 n/
9 is placed.

The display operation shown in FIG. 7 is also exactly the same as the operation described in FIGS. 5 and 6. That is, a selected heat generating resistor among the heat generating resistors 23 is energized and heated, and this core layer is formed in the core layer of the optical waveguide hole 2j that intersects with the energized and heated heat generating resistor. Boiling occurs and the bubbles described in FIG. 1 are formed in this core layer. At this time, the light emitting diodes of the selected light emitting diode element array/row emit light to cause light to enter the core layer of the selected optical waveguide hole. As a result, the path of the light that has been propagated through the bubble in the core layer of the selected optical waveguide while being totally reflected by the boundary between the core layer and the cladding layer is disturbed, as described in Fig. 1. And at least some of that light is in the cladding layer! , 2, this light is scattered by the light diffusion layer 27 and exits from the display element 2/ as display light. In this way, the heat generating resistor 23 is appropriately selected and heated by electricity, and at the same timing, the light emitting diodes /9a, /9b of the light emitting diode element row /9 are heated.
, / 9 c.../9n is selected and displayed as a dot, and this operation is repeated one after another, using the display elements, , 2/ as one screen! It can be displayed dimensionally. Note that the bubble formed in the core layer of the selected optical waveguide hole is cooled and disappears immediately before the next optical scan, so there is no problem in the next display.

In addition, in the configurations shown in FIGS. 5 to 7 above, in practice, the heating resistor can be manufactured with a density of g wires/lIa~/Otsu wires/■, and the density of the optical waveguide is g wires/lIa~/Otsu wires/■. It is possible to manufacture optical waveguide holes with a density of 11 to 76 holes/parallel.

FIG. 1 is a block diagram of the entire display device as an application example of the present invention.

Referring now to FIG. 6, an example in which each component of the display element whose structure is shown in FIGS. 6 and 7 is driven by Mad'J will be described in more detail. 3.2 is the row axis selection circuit, which includes bamboo wheel drive circuits 34tA, 3gB, 3gC...34
It is electrically coupled to tZ by a signal line, and furthermore, the bamboo wheel drive circuit 34th has a light emitting diode (3 ga,
311b, , H'c...3Qz) to the light emitting diode 34'a, the bamboo wheel drive circuit 341B to the light emitting diode 311tb, and the same bamboo wheel drive circuit 3'IC to the light emitting diode 3C... Bamboo wheel drive circuit 3'1.
Z are respectively coupled to the light emitting diodes 3'lz. Moving axis selection circuit 3/ and moving axis driving circuit ft6JJA, 33'B・
...33Z and heating resistor 3o a, 3 otsu b...
The same applies to the mutual relationship between 3rd party and 2nd party. The image control circuit 30 includes a row axis selection circuit 3.2 and a moving axis selection circuit,
, 3/ are electrically connected to VC by a signal line. , 3S
a, Jjb, 3. ! ;c...3! ;z is light emitting diode 3ga, 3'lb, 3gC...34'
7. For example, an optical waveguide having the basic configuration shown in FIGS. 1 to 3 is provided corresponding to each of the following. 3θ is an image control circuit, and by outputting the image control circuit, the row axis selection circuit 3. ．． 2 is an axial optical waveguide 33a, 3
! ;b, 3 J c-・337. The moving axis selection circuit selects which optical waveguide should be selected, and the moving axis selection circuit also selects the heating resistors 3a and 3b as moving axes.
36z which heating resistor should be selected.

Here, the light emitting diode J'@a, Job, 3'l
c...3g2 corresponds to the light emitting diode shown in FIGS. 6 and 7, and the optical waveguides 3j a, Jj b, 33
c-=33z corresponds to the optical waveguide or optical waveguide hole shown in FIGS. 3 and 7, and heating resistors 36a, 3b... (The heating resistor shown corresponds to the figure.

Next, referring to the drawings, an explanation will be given of the operation of driving the display devices shown in FIGS. 6 and 7, for example. If the υ row axis drive circuit 3'lh is selected by the command signal from the image control circuit 3θ, the bamboo wheel drive circuit 3'lA will remain in a conductive state for a certain period of time.
During this time, the light emitting diode 3a emits light. Light emitted from the light emitting diode 3'i'a is guided to the optical waveguide Jja. Next, when the bamboo wheel drive circuit 3'lB is selected, the light emitting diode 3'lb similarly emits light, and the light is
An optical waveguide 3sbK is guided. In this way, the light is line-sequentially scanned for each of the optical waveguides Jja, 3, ffb, 3jc, . . ., JjzK. On the other hand, the video signal, which is one of the image control signals from the image control circuit 30, is output from the outer axis selection circuit 3/
When VC is input, the moving axis selection circuit 3/
selects a heating resistor as a predetermined moving axis. for example,
When the moving axis selection circuit 3/ selects the heating resistors 36a and 3Z, the column axis drive circuits 33h and 33z select the moving axis selection circuit 3/
In response to the 33h row and 33Z row selection signals emitted from the 33h row and 33Z row selection signals, the heating resistors 3o a and 3otsu z are energized and heated. As a result, the optical waveguides Jj a, 33; b, 3.5 c..., which intersect with the heating resistors 36th and 3b, 2
3! ; The core layer portion of z is heated to such an extent that boiling occurs and bubbles are generated. Note that this bubble is cooled, disappears, and returns to its original state when electricity is cut off by an off signal to the heating resistor 36a1J6z. In this way, if the selection of the nail shaft, for example, the selection of the optical waveguide 3ja and the moving shaft, are made in synchronization, in this example, the heating resistors 36a, 36a, 36a, 3b2, which are selected and heated with electricity, are selected. Crossing point (selected point) with optical waveguide 15a (, 3ja, 36a
) and (3,!; h, 3 Otsu 2), respectively. In this way, the optical waveguides 33a, 33b, Jjc, etc. as nail shafts are controlled by the signal command of the image control circuit 3θ.
・・3Sz and heating resistor 36&, 3gb as a moving axis
... Two-dimensional display can be performed by appropriately selecting J 6z and operating it as described above.

In addition, examples of the material for the heating resistor mentioned above include metal compounds such as hafnium boride and tantalum nitride, and transparent conductors such as indium tin oxide (abbreviated as I, T, O). .

FIG. 2 is a partially exploded schematic perspective view of another embodiment of a display to which the principle of optical path modulation of the optical element shown in FIG. 1 is applied.

In Fig. 2, Daotsu is a flat optical waveguide as an optical waveguide panel, which is composed of a Fujirad layer 3.9s and a cladding layer 3, which is composed of a flat plate-like member with a relatively low refractive index. 413 and a core layer with a relatively high refractive index made of the liquid etc. mentioned in the explanation of Fig. 1, and its cross section is similar to Fig. 1 and Fig. β (a) excluding the heating element. It's exactly the same.

riθ is a linear light source, and the illumination light flux emitted from it is ! is focused through a cylindrical force lens and is incident on one end of the core layer. Reference numeral 7 denotes a heat generating element, the detailed configuration of which is shown in Fig. 1θ. Guga, Gugb,
gu gc - gu t is the column conductor, gu a, g'7b...
In column 9, there are single row conductors, which are made of a metal film with good conductivity.
....Dad t (hereinafter abbreviated as column conductor) and row conductor 11t'7a, 6'li'b...419k (
A heating resistor element serving as a heating resistor is interposed between each intersection with the row conductor 2).

Figure 1θ is a partially fragmented perspective view of the heating element gua;
9a, 19b, 9c and 19d are the row conductors, and 9a, 19b, 9c and 19d are the column conductors. The row conductor wires and the column conductor wires intersect each other at approximately right angles, and a heating resistor element is interposed at the intersection. For example, for row conductor 9a and column conductor 9a, a, good, 4
#c%4. ! The intersecting partial pressure with ra is the heating resistance element j
0a%30b, 3;Oc%jod are intervening, respectively.

Hereinafter, when referring to the entire heat generating resistor element, the heat generating resistor element S
It is called θ. Note that a film made of a non-conductive layer 1i1E (not shown), for example 5i02, is provided between the row conductor 4t without the heating resistive element jθ and the column conductor 4t.

Next, the operation of the display device according to the present invention will be explained with reference to FIG. 2 and FIG. 1θ. The illumination light beam 2 from the linear light source 9θ enters from one end of the core layer 4t9 of the planar waveguide via a cylindrical lens. core layer q4
When t is not heated by the heating element 117VC,
This illumination light flux q2 propagates within the core layer 4t and emerges from the other end of the core layer, similar to the principle described in FIG. 1.

Now, if an appropriate row conductor is selected from the row conductor group 2 and an appropriate column conductor is selected from the column conductor group, the heating resistor at the intersection of the selected row conductor and column conductor The element is electrically heated. For example, row conductor '%7a is selected, column conductor 4tgb, &,! Suppose that ra is selected and a voltage is applied between the row conductor 9a and the column conductors gb and ga. At this time, the heating resistive elements 3 located at the intersections of the row conductors 9a and the column conductors gb and gd, respectively.
0b, 36)d are heated by electricity. This heat, this heating resistance element! ; Ob, cladding layer 1l- on 30d
3 to the core layer Google. Since this is K,
The core layer is the heating resistor element 30b,...! ;OdK partially heats two parts and boils, forming bubbles as shown in FIG. At least a part of the illumination light flux that reaches the bubble in the illumination light flux group 3 that has propagated within the core layer layer due to this bubble (not shown) is disturbed in its path and passes through the cladding as explained in FIG. The light passes through the layers and is emitted to the outside of the display element 4t6 as display light.

In this way, two-dimensional display is possible by appropriately selecting the row conductors l12 and column conductors.

Note that the circuit configuration and operation for driving the above-mentioned display device are shown in FIG.
'b, 3'Ic-3'lz Optical waveguide 3. ! ; a, 33; b, 33c...3
3z and heating resistor 3ga134b...3otsuz
Remove the nail shaft drive circuits 3gA, 3gB, 34tC
...Connect each of the row conductor getters shown in FIG. 2 to 3'lZ, and drive shaft drive circuits 33h, 33B...
・33Z K By connecting each of the column conductors <tg shown in FIG. 2, the display device shown in FIG. 2 can be driven in the same manner as explained in the first drawing.

Also, the row conducting wire 4t in Fig. 1θ? and column conductor l/! Instead, a heat generating resistor may be provided, and instead of the heat generating resistor element jθ, a thermally conductive and insulating member may be provided to constitute the heat generating element. In this case, the area where the heat-generating nail shaft and outer shaft heat resistors intersect is heated to 100%, so bubbles as shown in Figure 1 are formed in the core layer above this heated area. It is formed.

The core layer heated by one of the heating resistors other than the intersection does not boil, and therefore no bubbles are formed, so there is no problem with display.

FIG. 1 is a schematic perspective view of an embodiment of a display device to which the principle of optical path modulation of the optical element shown in FIG. 7 is applied.

In Fig. 1/, j is a flat optical waveguide serving as a display element whose cross section is similar to the optical element shown in Fig. 7;
Infrared absorbing layer j4t1 A thermally conductive cladding layer sS made of a flat member with a relatively low refractive index, a core layer SB made of the above-mentioned liquid etc. with a relatively high refractive index, A light-transmitting cladding layer j7 made of a low plate-like member is laminated in this order. however,
The portion of the planar optical waveguide S except for the infrared absorbing layer sit is referred to as an optical waveguide panel. , 5/ is a linear light source for illumination, j-2 is a cylindrical lens, and the linear light source S/
This is for converging the illumination light beam j3 from the optical waveguide jg and guiding it to the core layer of the flat optical waveguide jg.

4.2 is an infrared beam emitted from a radiation generating means (not shown) (for example, a radiation generating means composed of a laser oscillator, etc., which will be described later). This infrared beam!
is the locus 6 on which infrared absorbing layer Sll of the planar optical waveguide j
/ as shown! Dimensionally scanned. It is assumed that the infrared beam 4 is modulated by a video information signal. j9 is a bubble and infrared beam! The infrared absorbing layer jF in the irradiated area generates heat, and this heat is transmitted to a part of the core layer S B via the cladding layer Jj, and the core layer j
This is a bubble formed when a part of B is heated to the extent that boiling occurs. Otsu θ is the illumination light flux 53 that propagates in the core layer St, and the light that reaches the bubble j9 is disturbed, and at least a part of the light reaches the cladding layer j.
This is the emitted light as display light emitted to the outside of the flat optical waveguide 5g via 7.

Next, the operation of the display shown in FIG. 1 will be explained. An illumination light beam j3 from the linear light source S/ is converged and incident on the core layer 5B of the planar optical waveguide j via the cylindrical lens 5.2. The infrared beam B is connected to the infrared absorbing layer S
When no bubble S9 is formed in the core layer SB, the illumination light flux j3 incident on the core layer
The light is repeatedly totally reflected at the boundary surface due to the difference in refractive index between the two core layers S, propagates through the core layer S of the planar optical waveguide, reaches the other end of the core layer, and exits. In this state, a modulated infrared beam is sent! irradiates the bottom surface of the infrared absorbing layer while drawing a trajectory.

Infrared beam now! Assume that the infrared absorbing layer 3 in the illustrated portion is irradiated while drawing a locus 6/.

This heats the infrared absorbing layer 5-1, and this heat is transferred to the core layer j-2 through the cladding layer 5j, causing a portion of the core layer j-2 to boil and to be heated as shown in FIG. A bubble S2 like this is formed.

The illumination light flux propagating in the core layer j as described above, 5
When a portion of the light beam reaches this bubble j5', the course of the light beam is disturbed by the bubble S7 as described in FIG. A portion of the light beam whose course is disturbed passes through the cladding layer S7 as described in FIG. 7, and is emitted to the outside of the planar optical waveguide 5 as an emitted light beam θ as display light. In addition, when the infrared beam 62 is no longer irradiated to the part 541 of the infrared absorbing layer 541 where the internal pressure of the core layer j9 has been formed, and the heat supply is cut off, this bubble j9 will naturally disappear. Regardless of whether it is cooling or forced cooling, it is cooled and disappears, so that the emitted light sensitivity θ as display light is no longer emitted from the cladding layer j7. - In this way, a large number of bubbles are formed in the core layer j6 according to the optical modulation of the infrared beam O2, and the planar optical waveguide S' is formed as one screen! This enables dimensional display.

In addition, in order to increase the optical waveguide efficiency, a heat generating element is used instead of the flat optical waveguide jg, but the parts shown in FIGS. 2(b) and 5 are different.
It is also possible to use tubular optical waveguides arranged in close rows horizontally as shown in Figures 6 and 6, or to use optical waveguide holes as shown in Figure 7. Of course.

1 and 2 are perspective views of one embodiment of a scanning mechanism for scanning an infrared beam over a display such as that shown in FIG.

In Fig. 7.2, an infrared beam 67 outputted from a laser oscillator Otsu 3 as a laser light source passes through a thin film waveguide deflector 6da and a lens Otsu j, and then enters a galvano mirror.
While being reflected by the infrared absorbing layer 6, for example, the surface of the infrared absorbing layer 5 of the flat optical waveguide 5 shown in FIG. In addition,
The galvanometer mirror 6B contributes to the scanning of light in the direction of the arrow a, and the thin film waveguide type deflector 6 contributes to the scanning of the light in the direction of the arrow. Further, one of the galvanometer mirror 66 and the thin film waveguide type deflector 6da serves as a horizontal scanner, and the other serves as a vertical scanner.

In addition to this, we also combined galvano mirrors and polygons! One example is a dimensional scanning mechanism.

FIG. 73 is a block diagram of an entire display device as an application example of the present invention, particularly a display device using a modulated infrared beam.

7θ is a video generation circuit that generates a video signal; 7/ is a control circuit that controls the video signal and supplies this signal to the video amplification circuit 73 and horizontal and vertical drive circuits 7.2; 7S is a laser light source; is an optical modulator that modulates an infrared beam from a laser light source according to a signal from an image amplifying circuit 73, and the light modulated by the optical modulator 711 enters a horizontal scanner 7B or a vertical scanner 77. Further, the horizontal scanner 7g and the vertical scanner 77 operate in response to drive signals synchronized with video signals from the horizontal and vertical drive circuits 7 and 2, respectively. The infrared beam from this scanner is incident on the infrared absorbing layer of the display element 77.

Further, the display element 72 is configured so that light from the illumination light source g0 enters the core layer thereof. The specific configuration of the scanning mechanism 7B is described in Section 1. ．． It is partially shown in FIG. 2 as an example, and the specific structure of the display g/ is shown as an example in FIG.

The video signal output from the video generation circuit 7θ is sent to the control circuit 7
/ is amplified by the video amplification circuit 73. The optical modulator 7da is driven by the input of the amplified video signal and modulates the infrared beam emitted from the laser light source 7j. on the other hand,
A horizontal synchronization signal and a vertical synchronization signal are outputted from the control circuit 7/, and drive the horizontal scanner 7 and the vertical scanner 77 via the horizontal and vertical drive circuits 7 and 2, respectively. In this way, a thermal three-dimensional image consisting of bubbles is formed within the core layer of the display element 7. The subsequent configuration and operation of the display g/ is as described above in FIG. 1/, and will be omitted here for simplicity. Note that when receiving TV radio waves, a receiver may be used instead of the video generation circuit 70.

In addition, a heating resistor as a heating element of the display shown in FIGS. S to 7 and FIGS. 2 to 1/FIG. A heat generating element can also be included in the optical waveguide panel by providing it at the boundary between the core layer and cladding layer of the panel. In this case, even if a heat generating element is provided at the boundary between the core layer and the cladding layer, when the heat generating element generates heat and is not heating the core layer, the light propagating within the core layer and the heat generating element If the total internal reflection condition between
Display on the display device can be performed using the same operation as the light modulation principle and display principle shown in FIGS. 1 to 9.

In addition, as a means for absorbing or alleviating the pressure increase due to the generation of bubbles, it is preferable to provide a well-known pressure absorbing means or pressure alleviating means (not shown) separately.

As explained in detail above, the main effects of the present invention are that / Since it is possible to arrange seven microscopic vapor bubbles in high density as a unit of display pixel, high-resolution image display is possible. can.

By adjusting the duration of the vapor bubbles in the liquid layer as display pixels, it is possible to easily display still images or moving images including slow motion.0 3 The structure of the optical element is relatively simple. Because of this, it has excellent productivity, and the elements have high durability and reliability.

Can be adapted to a wide range of drive systems.

There are many things that can be mentioned.

[Brief explanation of the drawing]

FIG. 7 is a schematic sectional view for explaining the operating principle of the optical element as a light modulation element or display element according to the present invention;
Figures (a) and (b) are schematic cross-sectional views of the optical element shown in Figure 1, and Figure 3 is a schematic cross-sectional view of the optical element shown in Figure 1 with a light diffusion layer provided. , FIG. 9 is a schematic sectional view for explaining another operating principle of the optical element as a light modulation element or display element according to the present invention, and FIGS. Schematic perspective view of display device, etc., g
The figure is a block diagram of a display device as an applied example of the present invention, FIG. 2 is a schematic structural perspective view of a display device as an applied example of the present invention, and FIG. 70 is used for the display device of FIG. 2. FIG. 1 is a schematic perspective view of a partial configuration of a heat generating element, FIG. 1 is a schematic perspective view of a display device, etc. as an application example of the present invention, and FIG. FIG. 73 is a block diagram of a display device as an application example of the present invention. /, Google, S6; Core layer, 3.2.2. ．． 26. 31 das 5.55. j7
．． ．． 2"; Cladding layer 9,978 heating elements '@a, zb, ・ /4', 23, 36a, 3 ots, = -3 ot,; heating resistor j; switch ot, /j'a, / , 5'a, , S, O';Buffer; Light (in the visible range) and O θ5g'; Emission light?, , 277 Light diffusion layer /θ, Sg; Infrared absorption layer //
;Infrared rays /2. ;Observer/j;Optical waveguide/7a, /7b・/,7n;Light-emitting diode/9a
, /9b -/9n; Light emitting diode, 2j; Optical waveguide hole 3θ; Image control circuit 3/; Column width selection circuit
32: Nail axis selection circuit 33A, , 3dB ・= , 33
Z; Dynamic axis drive circuit 3d, 3gB, JgC...3g 2; Chamber axis drive circuit, 3'la, , 34tb, , 3'
lc -3'lz; light emitting diode 33a, j! ;
h, 3.5c -JJ'z; optical waveguide θ, j/;
Linear light source; Row conductor 1I: Column conductor 5θ; Heating resistor element 2; Infrared beam 7θ; Image generation circuit 7/; Control circuit 7.2; Horizontal and vertical drive circuit 73; Image amplification circuit 7; Light Modulator 7S; Laser light source 77, 7g
;Horizontal and vertical scanner 79;0 for display element;Illumination light source r-12 Fig. 1 Fig. 2 Fig. 3 Diagram 12 Fig. 5 Fig. 7 Fig. 9 Fig. 10 Fig. 12 Fig. 13 Fig. 1 0 authors Takashi Noma No. 2 Canon Co., Ltd., 3-3 O-i Shimomaruko, Ota-ku, Tokyo 0 authors Hirotsugu Takagi 3-30 Se, Shimomaruko, Ota-ku, Tokyo 0 authors No. 2 Canon Co., Ltd. Author Nakazawa Mitsunobu 3-30 Shimomaruko, Ota-ku, Tokyo (within No. 2 Canon Co., Ltd.) Inventor: Kunio Ozawa (within Canon No. 2 Co., Ltd., 3-309 Shimomaruko, Ota-ku, Tokyo)

Claims (1)

[Claims] Optical waveguide Q″) whose basic structure is a core layer made of a liquid with a relatively high refractive index and a cladding layer made of a part 751 with a relatively low refractive index covering the core layer. 1. An optical element comprising a heating element.