JPS59135433A - Optical element - Google Patents

Abstract

PURPOSE:To enable image display with high resolution by consisting an optical element of a core layer composed of a member having a relatively high refractive index and heating the core layer by heating elements to the extent of avoiding boiling the core layer if said core layer is liquid. CONSTITUTION:An optical element consists of an optical panel 16 constituted by arraying plural pieces of optical waveguides each consisting basically of a core layer 1 composed of a member having a relatively high refractive index and a member having a relatively low refractive index and covering the layer 1, and heating elements 47 for heating the prescribed part of the waveguides 15. The element is so arranged that the core layer 1 (44) is heated by the elements 47 to the extent of avoiding boiling the layer 1 if said layer is liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel optical elements, particularly optical elements used for light modulation or display, optical devices using the same, and operating methods thereof.

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

In addition, attempts have been made to put liquid crystal panels into practical use (IJ Lux) as an alternative to CRTs, but there are still issues with driveability, display performance, reliability, and production. I have not been able to obtain anything that is completely satisfactory in terms of performance and durability. Furthermore, optical shutters that utilize liquid crystal light valves are attracting attention as optical path modulating elements.

However, the above-mentioned devices have a disadvantage in that they require a complicated and expensive optical system. Therefore, an object of the present invention is to overcome the disadvantages of the prior art and to eliminate the need for a complicated and expensive optical system. It is an object of the present invention to provide an optical element that can realize a simple light modulation device or display device without using the same, an optical device using the same, and a method for operating the same.

Furthermore, another object of the present invention is to provide an optical element with excellent driveability, reliability, productivity, durability, etc. by eliminating the need for a complicated and expensive C☆+7 optical system, and an optical device using the same. The object of the present invention is to provide these operating methods.

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. 7 is a partially schematic vertical cross-sectional view of an undiscovered optical element, and Fig. 1 (a) is a cross-sectional view of an optical element having a cross section as shown in Fig. 1, cut along the line A'-. It is a partial schematic cross-sectional view at the time. In Figures 1 and 2 (a), / is a cladding layer made of a material having a relatively higher refractive index than 3, and is a layer forming an optical waveguide, similar to the core of an optical fiber. It is called the core layer because it performs several functions. As the core material of the optical fiber, generally, glass or plastic with good transparency is used, but the core layer constituting the optical element according to the present invention is not limited to these solid materials, but rather, the core material of the present invention In order to achieve the above objectives, the core layer/
As will be described later, it may be preferable for the material to be composed of a liquid or a fluid. In addition, the thickness of the core layer is preferably within the range of /μm to /gourd.
is a cladding layer corresponding to the cladding of an optical fiber, which covers the core layer from above and below.

Note that this cladding layer 3 has a refractive index that is relatively lower than that of the core layer in order to propagate light within the core layer by utilizing total reflection of light at the interface with the core layer. (However, the cladding layer may be opaque.)
. Next, partially heat the core layer/ (however, in the case of core layer/ker liquid, heat the core layer/to such an extent that boiling does not occur in the core layer/
heat up. ) for both cladding layers λ.

In this embodiment, the car is placed in contact with the outside of the cladding layer.

Further, this heat generating element may be arranged close to the outside of the cladding layer. Further, the heat generating elements are arranged on the entire outer surface of the striped cladding layer, or in sections such as dots, islands, dotted lines, or dotted rows.

In the case of this embodiment, as shown in FIGS. 1 and 2(a), as a heat generating element, one end of bi is connected to the ground side and the other end is connected to each electrode (not shown). Heat generating resistors 4a, 4b, . S(,ya,5b
...) are switches, and one end of each is connected to a common power supply voltage, and the other end of each is connected to the heating resistors ll+a, 4'b... Each is connected to an electrode (not shown). B is a heating region formed in the core layer. For example, when the switch f5b is turned on, the heating resistor 7b is heated by electricity, and this heat is applied to the cladding layer. 7 shows a region with a relatively high temperature and a changed refractive index formed within the core layer/ by being transmitted to the core layer/ through the core layer/. 7 is incident on the core layer/ and propagates within the core layer/. Light in the visible region, g is emitted light emitted from the core layer/through the cladding layer 3, and 7.2 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 FIG. 7 and FIG. 2(a). When the core layer is not heated and its refractive index is uniform, the cladding layer, which has a relatively low refractive index,
3 with a relatively high refractive index (
・When light 7 is incident on core @/, it is totally reflected at the interface between core layer / and cladding layer 3, so light 7 is totally reflected many times at these interfaces and returns to the core. Propagating within a layer and proceeding to the other end is known from the principles of optical fibers (also referred to as leading wave tubes) and thin film optical waveguides.

At this time, the observer/observer separated by the cladding layer 3
2, if there is a leakage of the light 7, a small amount of light will reach the emitted light g, but in reality, the light 7 hardly reaches the light 7.

Now, heating resistors 9a, 4b... are arranged in a dotted line pattern.
In order to energize and heat the heating resistor 4Lb, the switch tb is turned on as shown in FIG. By this electrical heating, the clad @Y portion and the core @/ portion in the vicinity of the heating resistor 41b are heated by thermal conduction, and a heated region B is formed within the core layer. Then, if the core layer/ is a member whose refractive index changes negatively with respect to temperature changes, that is, whose refractive index decreases as the temperature rises, it will be heated (However, if the core layer/ is a liquid, The core layer is heated to an extent that it does not boil.) A thermal gradient index region is formed in the heated region within the core layer. As a result, the path of the light that has reached this heating area B out of the light 7 is disturbed, and the condition of total reflection is therefore broken, so that a small amount of this light that has reached the heating area B (and some of it is The light passes through the cladding layer 3 and exits the optical element as an emitted light beam without propagating inside... Observation 87.
It appears as though the heat is emitting from the heating resistor llb. 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 resistor lIa, ;t)... is minute dot-like, this heating resistor +a, <zb...
The heating area B formed by energizing and heating... also becomes minute. The course of the light 7 is disturbed by this minute heating area B, and a part of the light 7 emerges from the optical element as the emitted light g, so the observer/2 sees the heating resistors qa, +b.
Visualize it as if it were a point of light. On the contrary, heating resistors lIa, 1Itb...
If it has any shape with a certain size, then
Observer/2 recognizes that such a shape is displayed.

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 of the set of dots in the heated area formed by heating the body allows the viewer to recognize various characters and images.

In this example, we will take as an example a case where the change in refractive index of the core layer with respect to temperature change is much larger than that of the cladding layer (for example, when the core layer is generally a liquid and the cladding layer is a solid). Therefore, the heated region formed by heating the cladding layer was not mentioned because its influence is small.

Furthermore, the larger the change in refractive index with respect to temperature changes,
A heating region with a large refractive index change is formed by a slight change in temperature, and the path of light is greatly disturbed by this minute heating region in the core layer with this power. Therefore, in order to obtain the above display effect, Needless to say, this is even more advantageous. Note that if the temperature change in the heated region formed in the core layer is △T, and the refractive index change at that time is ∆N, then the ratio of the refractive index change to the temperature change is 1△N/△T10. , solid, and gas. Therefore, a translucent liquid is suitable as a material for the core layer.

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. Specific examples of various organic solvents used for this include methyl alcohol, ethyl alcohol, 'n-furobyl alcohol, isopropyl alcohol, n-butyl alcohol, 5ec-butyl alcohol, and tart-
butyl alcohol.

Alkyl alcohols such as isobutyl alcohol, pentyl alcohol, hexyl alcohol, heftel alcohol, octyl alcohol, nonyl alcohol, decyl alcohol; for example, hexane.

Octane, cyclopentane, benzene, toluene.

Hydrocarbon solvents such as Kijirol; for example, R tetrachloride,
zHalogenated hydrocarbon solvents such as chloroethylene, tetrachloroethyl ray, tetrachloroethane, and dichlorobenzene; Ether solvents such as ethyl ether, butyl needle, ethylene glycol diethyl ether, and ethylene glycol monoethyl ether; For example, acetone.

Ketone solvents such as methyl ethyl ketone, methyl propyl ketone, methyl amyl ketone, and cyclohexanone; Ester solvents such as ethyl formate, methyl acetate, propyl acetate, phenylacetate, and ethylene glycol monoethyl ether acetate; Alcohol solvents such as diacetone alcohol Solvents; For example, amides such as dimethylformamide, do, and dimethylacetamide; Amines such as triethanolamine and jetanolamine; Polyalkylene glycols such as polyethylene glycol and polypropylene glycol; -1-synglycol. Propylene glycol.

Examples include fluorine glycol, hexylene glycol, alkylene glycols; polyhydric alcohols such as glycerin; petroleum hydrocarbon solvents and the like.

In addition, it is essential that the refractive index of the translucent liquid constituting the core layer is higher than that of the cladding layer Yu, 3, and the refractive index of the Fujirad layer is usually 2.3. 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. 7, in which a light diffusing layer is provided adjacent to the upper part of the cladding layer 3.

FIGS. 1 and 2 (Al at ℃, as shown above, the observer/2 sees at least part of the light 7 whose path is disturbed by the heating area B, that is, passes through the cladding layer 3. However, since the emitted light beam is somewhat directional depending on the shape of the heating area B, the viewing angle at which this emitted light g can be seen is limited. If a light diffusion layer is provided on the cladding layer 3 as shown in Figure 3, the light passing through the cladding layer 3 will be scattered by the light diffusion layer 9, making it difficult to see this scattered light. The resulting viewing angle is very wide, which is favorable for the observer.

The cross-sectional shape of the core@/ and the cladding layer 3 along the A'-p: line of the optical element shown in FIG. 1 is shown in FIG.
), but as shown in Fig. 2(b), there is also a core layer with a circular cross-section. cladding of
The general cross-sectional shape of 3 is a circle as shown in Figure 2. Although there are shapes such as a flat plate shape, etc., the present invention is not limited to these shapes.

FIG. 4 is a partially schematic vertical sectional view of another embodiment showing the basic configuration of an optical element according to the present invention using an infrared absorbing layer as a heat generating element.

In the figure, / may be either solid or liquid, but for example, the core layer made of the above liquid, λ, 3 is this core layer /
, 7 is light in the visible range that enters this core layer and propagates inside the core layer, g is the emitted light from light 7 that is emitted to the outside via the cladding layer 3, 2 is an observer. It should be noted that the refractive index of the members of the core layer is relatively higher than the refractive index of the members of the cladding layer 2.3, which are made of the members described in the explanation of FIG. 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. B is a heated region formed inside the core layer by heating the core layer, in which the infrared absorbing layer 10 is irradiated with infrared rays, and the infrared absorbing layer 10 in the irradiated area generates heat. is transmitted to the core layer/part through the cladding
/ is a relatively high temperature region formed by heating to an extent that boiling does not occur locally.

Next, with reference to FIG. V, 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.

When the infrared absorbing layer 10 is not irradiated with infrared rays //, therefore the core layer/ is not heated, and its refractive index is uniform, the light 7 incident on the core layer// is absorbed by the core layer/, and the CLA and RAD layers. It propagates within the core layer while being totally reflected at the interface with Y or 3. At this time, the light 7 passes through the cladding layer 3 and is viewed by the observer 7.
．． 2, so when observer/2 looks at this optical element, he cannot see any light.

Now, when the infrared ray // is irradiated with infrared absorption R10K as shown in the figure, the infrared absorption layer 10 in the irradiated area generates heat. This heat is transferred to the core layer through the cladding layer,
The core layer is heated to an extent that boiling does not occur, forming a heated region B in which a change in refractive index occurs in the core layer. here,
For example, if a material whose refractive index changes with respect to temperature change is negative is selected as a member of the core layer, the heating region B becomes a thermal gradient index region.

- As a result, the path of the light of the light 7 that has reached this heating area B is disturbed, the total reflection condition between the core layer and the cladding layer 3 is broken, and at least a part of this light passes through the core layer. The light passes through the cladding layer 3 and is emitted to the outside of the optical element as emitted light g without being propagated, reaching the viewer 7.2.

At this time, the observer perceives the emitted light g as if it were emitted from the infrared absorbing layer 10 in the area where heat is being generated. Note that if an optical sensor is placed in place of the observer/2, the emitted light g can be detected by entering the light receiving surface of the optical sensor (not shown).

Note that if the heating region B formed in the core @/ of the optical element having the configuration shown in FIGS. 1 to 4 is cooled (whether by natural cooling or forced cooling) by blocking the supply of heat, Since it disappears, all of the light 7 that has reached this part is totally reflected again at the interface between the core layer and the cladding layer and propagates inside the core layer. Note that in the embodiment of the optical element having the configuration shown in FIGS. As long as they match, the heating element may be provided inside the cladding layer or inscribed on the core layer side,
Alternatively, a combination of these may be used. The same applies to the mirror described later.

Furthermore, instead of the cladding layer 2 of the optical element having the structure shown in FIGS. 1 to 9, a mirror having a light-reflecting metal film formed on a substrate may be used. 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(8)(b) is applied. In Figure 5, /3 is the board,
On top of this, a large number of heating elements are formed in a striped manner.Heating resistors/+a
, /lb, /4tc/4tk (hereinafter referred to as heating resistor /da) are provided.

A large number of light guides each having a longitudinal direction perpendicular to these heating resistors/4' and having a bow layer and a cladding layer whose vertical and horizontal cross sections are shown in FIGS. 1 and 2(b). wave tube/,
An optical waveguide panel in which ffa, 15b', /, tc·15n (hereinafter referred to as optical waveguide/left) are closely arranged is provided on the heating resistor/.

72'' is a laser beam having a wavelength in the visible region, which is repeatedly scanned in the direction of the arrow in the figure and sequentially enters one of the core layers of the optical waveguide/S. /B is these laser beams/
, 2 shows a display element constructed of the above-mentioned components except for 2. Also, /, 5'a.

/! f'a is a heating region formed by heating the core layer of the optical waveguide/Sa (however, if the core layer is a liquid, the core layer is heated to a degree that does not boil).

However, heating regions formed in the core layer of the optical waveguide other than the core layer of the optical waveguide/Sa are not shown.

Now, when none of the heating resistors /l is heated by electricity, the core layer of the optical waveguide /S is not heated, so the heating area mentioned above in Fig. 1 is the core layer of the optical waveguide / left. Therefore, the laser beam 72'' incident on the core layer of the selected optical waveguide is the first one.
The light propagates within the leading wave tube while being totally reflected by the core layer and cladding layer described above in the figure, and is emitted from the other end.

Next, only the heating resistors /lAc, /llk are heated by electricity, and when the laser beam /j enters the optical waveguide /3, the heating resistors /llO, /lk are heated by electricity. A heated region (/3'h, /!;'h> for the optical waveguide/&aK is formed in the core layer of the leading waveguide /S that intersects with the resistor /llC, /4. Laser beam incident on wave tube 15a/Bama and both jaw heat areas/
&'a, /5'aK, the path of the light is disturbed as described in the explanation of Fig. 1, and part of the light passes through the cladding layer of the optical waveguide/Sa as shown by the arrow in the figure. The light is emitted to the outside of the display element/6 as display light.

Next, an appropriate number of heating resistors /2 is heated by electricity, and the laser beam /2 is made to enter the optical waveguide 15b.
5b is displayed. This is done one after another in the optical waveguide/j
O.../kn is repeated to display the display element/B in a dimension as one screen. Note that the heating region formed in the core layer of the optical waveguide 15a, for example, the heating region /5'a formed in the core layer of the optical waveguide 15a, and other optical waveguides formed together with /5'a, For example, the heated region formed in the optical waveguide /, tb is cooled and disappears, whether by natural cooling or forced cooling, when the laser beam /, 2 enters the optical waveguide 15b for the next display. Since it has returned to its original state, there will be no problem when the next optical waveguide/3b is displayed. That is, when the next optical waveguide 15b is displayed, the heating resistors /4'O, /11 . If you want to display the corresponding point on the earth, you can heat the heating resistor /77c, /llk again, and if there is no need to display it, /40
, /'+k will not be heated by electricity.

FIG. 4 is a schematic perspective view of an embodiment of a display device in which the display element shown in FIG. S is provided with a light source of a light emitting diode array.

In Figure 6, like the components in Figure 5, /3 is a substrate, /4t is a heating resistor, /S is an optical waveguide, and light-emitting diodes /7a, /7'O are placed on the incident surface side. .

The flat plate microlens array /g is arranged so that the light beam emitted from the light emitting diode array /7 consisting of /70.../'7n efficiently enters each of the corresponding optical waveguides /g. (However, this flat microlens array is not always necessary.) In addition, each light emitting diode /7B.

/7'o, /7cm/7n are respective optical waveguides /&&.

15b, /30.../'5n, respectively.

The display operation in the case of Fig. 6 is exactly the same as in the case of Fig. 5, and an appropriate number of the heating resistors/4 are heated with electricity, and the optical waveguide/left core portion intersecting with them is heated. A heating area is formed, and in parallel with this, a light emitting diode element array/corresponding to one of the corresponding optical waveguides/S that is desired to be displayed.
The light emitting diodes 7 emit light and cause light to enter the corresponding optical waveguides. Thereby, the display is performed by the heating area of the predetermined optical waveguide on the same principle as the display principle explained in FIG. 7 and the $s diagram. Light emitting diodes /7a, /7b of light emitting diode element row /7.

/7c.../'7n are emitted and scanned one after another, so that the display element /B is displayed as 7 screens in an Ω-dimensional manner.

However, in the configuration shown in Figure 6, 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. It is.

FIG. 7 is a partially fragmented schematic perspective view of another embodiment of a display device that utilizes the optical path modulation principle of the optical element shown in FIG. 1.

In FIG. 7, reference numeral 1.22 is a light-transmissive cladding layer composed 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. Otsu is a cladding layer composed of a thin plate-like member with a relatively low refractive index, for example,
Clad+! 2.2 is overlapped with the grooved side by heat fusion or the like and integrated with the cladding layer 22. Due to this, the groove of the cladding layer 22 becomes an elongated hollow hole hollowed out by the cladding layer 22. The large number of parallel, elongated cavities are filled with the liquid having a relatively high refractive index and serving as the core layer. By these, a large number of parallel optical waveguide holes J, ta, Job, 2! ;O...
, 2 left n (hereinafter referred to as optical waveguide hole 2 left) are formed. These cladding layers, 22, 2B and optical waveguide hole, 2S
are collectively called an optical waveguide panel. 73' is the board,
On this, a large number of heating resistors 23a, 23b are arranged in stripes.
, 23cm23k (hereinafter referred to as heating resistor 23)
is provided. The optical waveguide hole 2 left is provided perpendicularly on this heating resistor 23. Another more effective means of creating such a leading waveguide panel is to place $ on the heating resistor 23 disposed on the substrate/3'.
There is also a method of forming the cladding layer 2B by coating it with a low refractive index dielectric such as 1), and then bonding the substrate 73' and the cladding @n in which grooves are formed. , 27 is a light diffusion layer provided on the cladding layer 2.2, for example,
The upper surface of the cladding layer 22 has a finely uneven surface. The cross section along the longitudinal direction of the optical waveguide hole 2 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/9a is connected via a flat plate microlens array 20 on the incident surface side of the optical waveguide hole 2.

A light emitting diode element array /q consisting of /9b, /9c.../qn is arranged.

The display operation shown in FIG. 7 is also exactly the same as the operation described in FIGS. 3 and 6. That is, a selected heating resistor among the heating resistors 23 is heated by energization, and the portion of the core layer on the left side of the optical waveguide hole 2 that intersects with the heating resistor being energized and heated is heated. The heating regions mentioned in the figures are formed in this core layer. At this time, the light emitting diodes of the selected light emitting diode element row/9 emit light, causing light to enter the core of the selected optical waveguide hole. As a result, the path of the light that has propagated through the heated region of the core layer of the selected optical waveguide hole while being totally reflected by the boundary between the core layer and the cladding layer, as described in FIG. 1, reaches the internal thermal region. The light is disturbed, and at least a portion of the light passes through the cladding layer 22, is scattered by the light diffusion layer 27, and exits from the display element unit as display light. In this way, the heating resistor 23 is appropriately selected and heated, and at the same time, the light emitting diode array/
q light emitting diode /9a, /9b, /9c=-/7n
By selecting one of them and emitting light to display a dot, and repeating this operation one after another, it is possible to display an Ω-dimensional display using the display element 2/ as one screen. Note that the heated region formed in the core layer of the selected optical waveguide hole is cooled and desensitized just before the next light evacuation, so there is no problem in the next display.

In addition, in the configurations shown in FIGS. S to 7 above, in practice, the heating resistor can be manufactured with a density of g wires/mm to /Otsu wires/cod, and the density of the optical waveguide is g wires/rran. -, 20 pieces/f
1, and the density of the optical waveguide hole can be manufactured from g/tone to g/omoto/g.

FIG. 3 is a block diagram of a display device as an application example of the present invention.

In FIG. 3, an example in which each component of each display element whose structure is shown in FIGS. 4 and 7, for example, is moved in detail will be explained in more detail. 3 are front axle selection circuits, front axle drive circuits 3'lA, 3'lB.

31Ic...311Z are electrically coupled by signal lines, and furthermore, the front axis drive circuit 3IIA is connected to the light emitting diode element array <31Ia, 311b, 311a-, 311z.
), the front shaft drive circuit 311B connects the light emitting diode 311b to the light emitting diode 311b, and the front shaft drive circuit 3
11a is coupled to a light emitting diode 311c, and the front shaft drive circuit 31IZ is coupled to a light emitting diode 311c and a Δ diode 3/lz, respectively. Dynamic axis selection circuit 3/ and dynamic axis drive circuit 33A,
33B...33Z and heating resistor 3 Oa,
The same applies to the mutual relationship with 31゜b...3 Otsu 2. The image control circuit 30 is electrically connected to the front axis selection circuit 32 and the moving axis selection circuit 3/ by signal lines. 3! ;a, 3! ;b, 3! ;c-・----3! ;
Z is a light emitting diode 311a, 3'l'o, 311cm
-------An optical waveguide having the basic configuration shown in FIGS. 1 to 3, for example, is provided corresponding to each of the optical waveguides 341z and 341z. 30 is an image control circuit, and by outputting an image control signal, the front axis selection circuit 3.2 selects the optical waveguide 3! as the front axis. ;a, 35b, 3! ;o------...3! ;
The moving axis selection circuit instructs the moving axis selection circuit 3 to select which optical waveguide of 2, which heating resistor should be selected.

Here, the light emitting diodes 311h, 311. b,
3170...34tz corresponds to the light emitting diode shown in FIGS. 4 and 7, and the optical waveguide 3! ;? L,
3! ;b.

330...3. tZ corresponds to the optical waveguide or optical waveguide hole shown in FIGS. 6 and 7, and the heating resistor 36
a, 3 ot b...3 ot 2 correspond to the heating resistor shown in FIGS. 4 and 7.

Next, referring to FIG. 8, an explanation will be given of the operation of driving the display devices shown in FIGS. 4 and 7, for example. When the front axis drive circuit JlIA is selected by a command signal from the image control circuit 30, the front axis drive circuit 3+A is in a conductive state for a certain period of time, and the light emitting diode 34ta emits light during that time. The light emitted from the light emitting diode 311a is transmitted through the optical waveguide 3! ; Guided by 2L. Next, when the front axis drive circuit 3'lB is selected, the light emitting diode 311b similarly emits light, and the light is guided to the optical waveguide 3&b. Thus, each optical waveguide 35
a e3! b, 3. ! ;O...337. The light is scanned sequentially in parallel lines. On the other hand, the image control circuit 30
When a video signal, which is one of the image II control signals from select.

For example, the moving axis selection circuit 3/ is a heating resistor 34a.

If 31, Z is selected, the dynamic axis drive circuit 33fi, 33
2 is the 3-, JIA column emitted from the moving axis selection circuit 3/.

337 In response to the column selection signal, the heating resistor 31. h, semi-heat through 31°2. As a result, the optical waveguide 3 intersects with the heating resistor A, 3, and 2! ;a, 3. kb
, 3! C...The core layer portion of 3Sz is heated to such an extent that no boiling force of 1 is generated, thereby creating a heated region. t6, this heating area is the heating resistor 37. h, 3AZ
When the electricity is cut off by the off signal, it cools down and disappears, returning to its original state. Thus, the choice of front axis, e.g. optical waveguide,? , S-a and the moving axis are selected again, in this example, the selected heating resistors 3 a, 34Z and the selected optical waveguide 3!
; Intersection point (selected point) with 7L (35a).

Light is emitted from both 3otsu a) and (3!; a, 3otsu2), respectively. In this way, the optical waveguides 33h, 35b, 35 as the front axis are controlled by the signal command from the image control circuit 30.
C......? 5Z and heating resistor 3 as a moving axis
Ah, 31. By appropriately selecting 'o...3 and 2 and operating as described above, two-dimensional display can be performed.

In addition, examples of materials 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 ■・T-0). can.

FIG. 9 is a partially exploded schematic structural perspective view of another embodiment of a display to which the principle of optical path modulation of the optical element shown in FIG. 7 is applied.

In FIG. 9, 4t6 is a flat optical waveguide as an optical waveguide panel, and cladding liM '13, II 3 and these cladding Ii 41.3 are composed of flat plate-shaped members with a relatively low refractive index. .4ts and a core layer tl<2 with a relatively high refractive index made of the liquid or the like mentioned in the explanation of FIG. 7, and its cross section is similar to that shown in FIGS. a) Stopped (same.ll
O is a linear light source, and the illumination light flux lI2 emitted from it is converged through a cylindrical lens and sent to the core layer l
The light is incident on one end of the beam. Reference numeral 7 is a heat generating element, the detailed structure of which is shown in FIG. II g a
, lIg b , l1g c ・”・'l g
l is the column conductor, '1qa, 1Iqb---119
are row conductors, these are made of a metal film with good conductivity, and these column conductors 11ga, 'Igb, l1gc
-------11g1 (hereinafter abbreviated as column conductor 4tg) and row conductor 4'9a.

4t9b . . . 1I9k (hereinafter abbreviated as row conducting wire guts) are interposed between respective intersections with heat generating resistive elements as heat generating resistors. Figure 70 shows the heat generating element t
70 partially fragmented perspective view, 4t9a, 119b.

49c, I/lqd is the above row conductor, +, ga, <tgb
.

4tgc and llgd are the column conductors. The row conductor 9 and the column conductor 1Ig intersect at approximately right angles, and a heating resistor element is interposed at the intersection.

For example, the row conductor 4L9a and the column conductor lIga, +gb.

At the intersections with ii-ga and lIgd, there are heating resistive elements left Oa, 30b, !, respectively. sac,! ; Od is intervening respectively. Hereinafter, when referring to the heating resistive element as a whole, it will be referred to as the heating resistive element SO. Although not shown, a non-conductive film, such as 5101, is provided between the row conductor g and the column conductor g without the heating resistor element SO.

Next, the operation of the display device according to the present invention will be explained with reference to FIGS. 7 and 70. Illumination light flux 4' from linear light source G0
2 enters from one end of the core @q of the planar optical waveguide II via the cylindrical lens II/. When the core layer is not heated by the heating element guar, this illumination light flux '12 is the same as the core @4 as described in FIG.
L4 is propagated inside and ejected from the other end of the core layer 1III. Now, an appropriate row conductor is selected from among the row conductors tI9,
Assuming that an appropriate column conductor is selected from among the column conductors g,
The heating resistor element located at the intersection of the selected row conductor and column conductor is heated by energization. For example, assume that the row conductor 4tqa is selected, the column conductors l1gb and lIgd are selected, and a voltage is applied between the row conductor 4t9a and the column conductors 4tgb and lIgd. At this time, the heating resistive elements s, ob, and sod located at the intersections of the row conducting wire 11qa and the column conducting wire lIgb, <1d are heated by electricity.

This heat is transmitted to the core layer III through the cladding layer 3 on the heat generating resistive elements sob and sod. As a result, the core layer 1lll becomes the heating resistor element SOb, t
A portion a is partially heated by Od to form a heated region as shown in FIG. Due to this heating region (not shown), the illumination light flux '12 that has propagated within the core re 4t<z
As explained in FIG. 1, at least a part of the light that reaches the heating area is disturbed in its path, passes through the cladding layer IIS, and exits the display element 4 to the outside as display light. do.

In this way, two-dimensional display is possible by appropriately selecting the row conducting wires 9 and the column conducting wires itg.

Note that the circuit configuration and operation for driving the above-mentioned display device are as described in the third section.
The light emitting diode 34'a shown in the figure.

3'l b, 3'l c...-311z, optical waveguide 33a.

33b, 3! ;c...3 left z and heating resistor 3
4 a.

3 Otsu b...3 Otsu 2 removed, front axle drive circuit, ?
4A.

3'lB, 311C...3'lZ are connected to each of the row conducting wires l/19 shown in FIG. 9, and a dynamic axis drive circuit 33A.

33B...3. By connecting each of the column conductor wires shown in FIG. 7 to 3Z, the display shown in FIG. 9 is driven in the same manner as explained in FIG. 3. be able to.

Further, the heat generating element may be constructed by providing a heat generating resistor in place of the row conducting wire l19 and the column conducting wire l1g in FIG. 70, and providing a thermally conductive and continuous member in place of the heat generating element Gua 0. In this case, the part where the heating resistors of the front shaft and moving shaft intersect is particularly heated, so the core layer above this heated part is heated to a particularly high temperature as shown in Figure 1. A heating area is formed. As shown in Figure 1, the core layer heated by one side of the heat generating resistor other than the intersection part has a thick emitted light (there is no heating area high enough to emit light, so there is no problem in displaying it). ~・.

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

In FIG. 77, 5g is a flat optical waveguide serving as a display element whose folding surface has the same configuration as the optical element shown in FIG. A thermally conductive cladding made of a shaped member @r left!; A core layer S made of the above-mentioned liquid etc. with a relatively high refractive index; A transparent cladding made of a flat plate-like member with a relatively low refractive index. The sexual clad @ old 7 is constructed by multiplying H in this order.

However, from the left g of the flat optical waveguide P#4 to the infrared absorbing layer 5
The part excluding the optical waveguide panel is called the optical waveguide panel. Left / is a linear light source for illumination, S2 is a cylindrical lens, which converges the illumination light flux 3 from the linear light source / into a flat optical waveguide 5
The core IM of g is intended to lead to ff. The loco 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 6U is scanned in the a-dimensional direction on the infrared absorbing layer 54' of the flat optical waveguide 3g as shown by a trajectory B/. It is assumed that the infrared beam, ', A2 is modulated by the video information signal.

5q is a heating region, where the infrared absorbing layer 5G generates heat in the area irradiated with the 6 infrared beams, and this heat is transmitted to a part of the core 115B via the cladding layer 5&, and a part of the core layer SB is heated. (However, if core @ / is a liquid, core 1
■/ is heated to the extent that it does not boil. ). Of the illumination light flux left 3 propagating in the core layer S, the light that reaches the heating area 5 is disturbed, and at least a portion of the light passes through the cladding layer 57 to the flat optical waveguide 5g. This is the emitted light as display light emitted to the outside.

Next, the operation of the display shown in FIG. 1 will be explained. The illumination light beam 3 is converged and made incident on the core layer 5B of the planar optical waveguide 3g via the linear light source S/cylindrical lens 5.2. Infrared beam Oa has an infrared absorption of 1%
There is a heating area 39 in the core layer S that is not irradiated to jl.
When no is formed at all, the illumination light beam 53 that has entered the core layer S is repeatedly totally reflected at the total reflection boundary surface due to the difference in refractive index between the core layer left and the cladding @S or Shio 7. The light propagates within the core layer of the shaped optical waveguide, reaches the other end of the core layer, and is emitted. In this state, the modulated infrared beam 4 irradiates the lower surface of the infrared absorption layer Sll while tracing a trajectory. Now, assume that the infrared beam λ irradiates the infrared absorbing layer 3'l in the illustrated portion while drawing a trajectory O/. This heats the infrared absorbing layer SII, and this heat is transmitted to the core layer S through the cladding layer 15, heating a part of the core layer S, and causing the left side of the core layer to be heated as explained in FIG. 4. tr A heating region S9 whose refractive index has changed at a relatively high temperature is formed. Core layer S as above
When a portion of the illumination light beam 3 propagating in the interior reaches this heating region S9, the course of this light beam is disturbed by the heating region as described in FIG. 4.

At least a portion of the light flux whose path is disturbed passes through the cladding layer 7 as described in FIG. 4 and is emitted to the outside of the flat optical waveguide 3g as display light with an emission light sensitivity of 0. Note that when the infrared beam 6 is no longer irradiated to the part of the infrared absorbing layer SII corresponding to the part where the heating region 5q formed in the core layer S is formed, and the heat supply is cut off, this heating region Since the light 9 is cooled and disappears regardless of whether it is natural cooling or forced cooling, the emitted light θ as the display light no longer emerges from the cladding @ left 7. In this way, a large number of heating regions are formed in the core layer according to the luminous intensity of the infrared beam 6 units, making it possible to display the left side of the flat optical waveguide in the a dimension as one screen. It is.

In addition, in the display shown in Fig. 9 and Fig. 1/Fig.
If the core layer in the figure or the core layer on the left side in Figure 1/Figure 1 is a transparent glass flat plate, the cladding layer in Figure 7
13. The data or cladding layer 55,57 in Figure 1/Figure 1 may be air. In this case, the heating element shown in FIG. 9 or @// is disposed near the core layers qt, t or the core layer 5b.

In addition, in order to increase the optical waveguide efficiency, instead of using a flat optical waveguide, we used a tubular optical waveguide as shown in Figures Ω(b), s, and 4, although the heat generating elements are different. Of course, it is also possible to use optical waveguide holes that are closely arranged in a horizontal row, or to use optical waveguide holes as shown in FIG.

FIG. 1 is a perspective view of an embodiment of a scanning mechanism for scanning an infrared beam on a display device or the like as shown in FIG. 1.

In FIG. 72, laser oscillator A3 as a laser light source
The infrared beam A7 outputted from the thin film waveguide type deflector 4
After passing through Otori and Lens Otsu S, ゛Galvano mirror 6
While being reflected by B, the surface of the infrared absorbing layer B9 of the display element tg, which corresponds to the infrared absorbing layer Stt of the planar optical waveguide Sg shown in FIG. 77, is scanned at high speed. Note that the galvanic mirror 6 contributes to the scanning of light in the direction of the arrow a, and the thin film waveguide deflector 6 contributes to the scanning of the light in the direction of the arrow. Also, one of the galvanometer mirror 66 and the thin film waveguide type deflector 4 serves as a horizontal scanner, and the other serves as a vertical scanner.

Other examples include a two-dimensional scanning mechanism that combines a galvanometer mirror and a polygon.

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.

70 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 the horizontal and vertical drive circuits 72; 7S is a laser light source; and 7G is a laser The light modulated by the optical modulator '74, which is an optical modulator that modulates the infrared beam from the light source according to the signal from the image amplifying circuit 73, enters the horizontal scanner 7g or the vertical scanner 7+-77. Further, the horizontal scanner 78 and the vertical scanner 77 operate in response to drive signals synchronized with the video signals from the horizontal and vertical drive circuits 72, respectively. The infrared beam from this scanner is incident on the infrared absorbing layer of the display element 7q.

Further, the display element 7q is configured so that light from the illumination light source g0 enters the core 1 of the display element 7q. The specific configuration of the running mechanism 7B is partially shown in FIG. 72 as an example, and the display device g
The specific configuration of / is shown as seven examples in Fig. 1/.

The video signal output from the video generation circuit 70 is sent to the control circuit -
77 and is amplified by the video amplification circuit 73. The optical modulator 79 is driven by the input of the amplified video signal and modulates the infrared beam emitted from the laser light source 7S. 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 7g and the vertical scanner 77 via the horizontal and vertical drive circuits 7, respectively. In this way, a thermal two-dimensional image consisting of heated regions is formed within the core layer of the display element 79. The subsequent construction 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.

FIG. 11 is a partially schematic vertical cross-sectional view of the optical element for illustrating another principle of operation of the optical element according to the present invention.

In the first diagram, / is the core layer, -', 3 is the cladding layer that is transparent, 70' is the infrared absorbing layer that is transparent to visible light, and 7 is the core layer /. The light in the visible range is incident and propagated, and these components are almost the same as those explained in FIG. 9 except for the refractive index and translucency.

In the case of this example, a material whose refractive index changes negatively with respect to temperature changes is selected as the core layer member, and the cladding +1!3i
, 2' are selected to have positive refractive index changes with respect to temperature changes. / is an observer on the cladding layer 3 side, 72' is an observer on the cladding layer 2' side, and // is an infrared ray.

B' is a heated region formed in the cladding layer 2' and the core layer 2'. The refractive index of the region where the center temperature is high is high.

g is the emitted light emitted from the core layer/ via the cladding layer 3, and g' is the emitted light emitted from the core via the cladding layer 2' and the infrared absorbing layer/α.

When infrared ray // is not irradiated to infrared absorption @/α,
The light 7 propagates inside the core while being totally reflected by the interface between the core layer and the cladding layer Y' or 3. Therefore, since almost no light exits through the cladding layer j or 3, the observer/! , / , 2' hardly sees light.

Now, assume that infrared rays // are irradiated to the infrared absorbing layer /0'. The infrared absorbing layer tO/ in the irradiated area generates heat, and this heat is transferred to the cladding layer 2' and the core layer/, and the heated area of the core layer/and cladding @Y' is placed in a relatively high temperature region. A heated region B' with a changed refractive index is formed. The path of the light that has reached the heating region in the inner core layer of the inner heating region B' is disturbed, the total internal reflection condition is broken, and some of the light passes through the cladding@3 and becomes the emitted light G. The light is emitted to the outside of the optical element. Observer/2
can be visualized. In addition, the remaining light flux propagates through the heated region within the core layer while being refracted, but this refraction is further made so that it enters the surface of the cladding layer λ' at a shallower angle, that is, at an angle that increases the incident angle. Proceed to. However, the refractive index of the core layer/ is lower than that of other regions at the interface where the core layer / and the cladding layer a' are in contact, and also corresponds to the center of the recessed region O'. Since the refractive index is higher than that in other regions, the difference in refractive index between the core layer/section and the cladding layer Z section becomes very small, and therefore the critical angle of this section becomes very large.

As a result, a part of the light 7 that reaches the interface between the core layer and the cladding layer of the heating region 6' while being refracted through the heating region B' of the core layer 6' has a large critical angle at this interface. Therefore, the light is not totally reflected at this boundary surface, but passes through the cladding @λ' and the infrared absorption @70', and is emitted to the outside of the optical element as emitted light g'. This emitted light beam can be seen by the observer 7.2'. The remaining light (which may or may not be present) is totally reflected and propagates within the core layer. In this manner, by appropriately selecting the materials of the core layer/cladding layer λ', it is possible to provide an optical element that can be observed from both sides of the optical element.

Further, even if a transparent heating resistor as shown in FIG. 7 is used instead of the infrared absorbing layer 70' as a heating element, the emitted light can be seen from both sides of the optical element as described above.

It goes without saying that these optical elements can be applied to optical elements and optical devices such as the display and display device shown in FIGS. 5 to 13.

In addition, a heating resistor or an infrared absorbing layer as a heating element of the display shown in Figures 7 to 7 and 7 to 1 may be provided inside the cladding layer of the optical waveguide panel, or The heating 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 core 1 of light propagating within the core layer.
If the total internal reflection conditions between and the heat generating element are satisfied,
Figures 1 to 111. Display on the display device becomes possible through operations similar to the light modulation principle and display principle shown in the figure.

As explained in detail above, the main effects of the present invention are: (1) Since it is possible to arrange seven minute core layer heating regions in a high-density arrangement as a unit of display pixel, it is possible to achieve high resolution. Images can be displayed.

(2) Since the structure of the front element is relatively simple, its productivity is excellent, and the element is highly durable and reliable.

(3) Can be adapted to a wide range of drive systems.

(4) Since the display is performed by heating the core layer to a temperature below the boiling point instead of forming vapor bubbles, less power is required for the optical elements, which reduces the power consumption of the power supply unit, i.e., the light modulator and display device. can be made smaller.

(5) In devices that perform light modulation or display using vapor bubbles, there is a risk of damage to the optical device due to cavitation when the vapor bubbles disappear, but in the present invention, the core layer is simply heated to an extent that does not boil, so the device has extremely high durability.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view for explaining the operating principle of an optical element as a light modulation element or display element according to the present invention, and FIG.
Figures (a) and (b) are schematic horizontal cross-sectional views of the optical element shown in Figure 7, and Figure 3 is a schematic horizontal cross-sectional view of the optical element shown in Figure 1 with a light diffusion layer. Figure J 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 Figures S to 7 are schematic cross-sectional views for explaining other operating principles of the optical element as a light modulation element or display element according to the present invention. Figure S is a block diagram of a display device as an applied example of the present invention; Figure 9 is a schematic perspective view of a display unit as an applied example of the present invention; Figure 70 is a schematic perspective view of the configuration of a display device; 9 is a schematic perspective view of a partial configuration of a heat generating element used in the display device shown in FIG. 9, FIG. A schematic perspective view of a two-dimensional scanning mechanism used in a display element,'
! Figure 5/3 is a block diagram of a display device as an application example of the present invention, and Figure 11 is a schematic diagram for explaining another operating principle of the optical element as a light modulation element or display element according to the present invention. FIG. to l14/-156; core layer, 2.3. ．． 2.2.2 B, l13. '13. To! ;,
! ;7. ．． 2'2'; ri-y tsut' @ri, l/
-7; Heat generating element 11h, 41b, ---, l11.23.36h, 3 Otsu, 3 Otsu 2; Heating resistor S; Switch desk/S clause, /Da a, 5 Wa, Otsu'; Heating Region 7; (visible region) light g, O, g'; Emitted light 9.27; Light diffusing layer 10, IO',! r'l; infrared absorption layer //; infrared rays
/2. /2';Observer/left; Optical waveguide /7a,
/7b.../7n; Light emitting diode /qa, /qb...
・/9n; Light emitting diode 2S; Optical waveguide hole 30; Image control circuit 3/; Dynamic axis selection circuit 3; Row axis selection circuit, J
', J'A, 3J'B-33Z; Sub-shaft drive circuit 3'l
k, 3'lB, 3'IC-311Z; Bamboo wheel drive circuit 3
4ta, 311b, 3'1c-311z; light emitting diode 3! ;? r,,3A;b,3. ! ;O-,? 5Z
; Optical waveguide '70. ! ; / ; Linear light source 4t9; Row conductor 9g 1 column conductor SO; Heating resistance element 62; Infrared beam 70; Image generation circuit 7/; Control circuit 72; Horizontal and vertical drive circuit 73; Image amplification circuit 7da; Optical modulator 7S: Laser light source 77.7g; Horizontal and vertical scanner angle 79°; Display element gO; Illumination light source patent applicant
Canon Co., Ltd. Figure 1 Figure 2 Figure 3 Illustrated 11 Figure 4 Figure 5 Figure 7 Figure 6T2 Toro] 17 Figure 14 Continued from page 1 0 Inventor Takashi Noma 3-30 Shimomaruko, Ota-ku, Tokyo No. 2 Canon Co., Ltd. 0 Inventor: Nobutoshi Mizusawa, 3-30-2 Shimomaruko, Ota-ku, Tokyo, Japan 0 Inventor: Mitsunobu Nakazawa, 3-30-2 Shimomaruko, Ota-ku, Tokyo, 0 Inventor Kuni Ozawa, Canon Co., Ltd., 3-30-2 Shimomaruko, Ota-ku, Tokyo

Claims (1)

[Claims] A plurality of optical waveguides each having the basic structure of a core layer made of a material with a relatively high refractive index and a cladding layer made of a relatively low refractive index part 4- covering the core layer are composed of a plurality of optical waveguides. It consists of an optical waveguide nominal and a heating element for heating a predetermined part of the optical waveguide, and especially when the core layer is liquid,
An optical element characterized in that the core layer is heated by the heating element to an extent that the core layer does not boil.