JPH1196819A - Polarized lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polarized lighting system having high efficiency, high luminance of illuminating light, and low power consumption by effectively conducting polarization separation. SOLUTION: A device A1 is provided with a fluorescent lamp 1, a light guide body 3 for causing light from the fluorescent lamp 1 to be incident on one side face 3a and guiding the incident light to between an upper face 3d and a lower face 3c perpendicular to the side face 3a and parallel to each other, reflection plate 5 arranged on the lower face side 3c of the light guide body 3 for reflecting the guided light, and a polarization separation plate 7 arranged on the upper face 3d side of the light guide body 3, penetrating P polarization light, a certain polarization direction component in the guided light, and reflecting S polarization light, a component perpendicular thereto. By effectively conducting polarization separation, high efficiency, high luminance of illuminating light are achieved, and moreover with low power consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for a polarized lighting device used for a light source such as a liquid crystal display.

[0002]

2. Description of the Related Art FIG. 38 shows an example A of a conventional polarized light illumination device.
FIG. In FIG. 38, 501
Reference numeral denotes a fluorescent lamp as a light source, and reference numeral 502 denotes a reflection cover for reflecting and condensing light from the fluorescent lamp 501. A light guide 503 has diffusion dots 504 formed on its lower surface 503c by silk printing. Reference numeral 505 denotes a diffuse reflection plate for diffusing light emitted downward from the light guide 503 and returning the light to the light guide 503 again. 50
Reference numeral 6 denotes a diffusion plate for diffusing light emitted upward from the light guide 503. Reference numeral 507 denotes a prism sheet for directing the radiation angle distribution of light emitted upward from the diffusion plate 506 to a position directly above. 50
Reference numeral 8 denotes a polarization separation plate that transmits light in a certain polarization direction (P polarization) and reflects light in a polarization direction (S polarization) perpendicular to the light emitted upward from the prism sheet 507. To emit only the P-polarized light further upward.

In such a conventional configuration, the fluorescent lamp 50
The light emitted from 1 is condensed on one side surface 503 a of the light guide 503 by the reflection cover 502 and enters the light guide 503. The incident light propagates through the light guide 503 within a critical angle, and the diffusion dots 504 printed on the lower surface 503c thereof.
Spread by. Part of the diffused light is emitted above the light guide 503, and another part of the diffused light is emitted below the light guide 503. The rest of the diffused light propagates through the light guide 503. The diffused light emitted downward from the light guide 503 is diffusely reflected by the diffuse reflection plate 505, returns to the light guide 503 again, and a part thereof is emitted upward. Light emitted above the light guide 503 is diffused by the diffusion plate 506,
The emission angle distribution can be shifted right above by the prism sheet 507. Of the light that has passed through the prism sheet 507, P-polarized light passes through the polarization splitter 508, and S-polarized light is reflected by the polarization splitter 508. S reflected here
The polarized light returns to the light guide 503. The S-polarized light passes through the diffusion plate 5
06, the diffusion dots 504 and the diffusion reflection plate 505 depolarize little by little, and when returning to the polarization separation plate 508, the component converted to P-polarized light passes through the polarization separation plate 508.

[0004] The remaining component of the S-polarized light is separated by a polarization splitting plate 50.
8 again, and the above operation is repeated. That is, the polarized light separating plate 508 is used for the purpose of increasing the luminance of the illumination light by reusing the component of the S-polarized light by the polarized light separating action, compared to when there is no S-polarized light.

[0005]

In the above-mentioned conventional configuration,
Light absorption by the diffusion dots 504 occurs. This light absorption increases due to multiple reflections in the light guide 503 and with the polarization separator 508. As a result, there has been a problem that the polarization separation effect cannot be effectively utilized, and the luminance of the illumination light cannot be sufficiently increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a main object of the present invention is to make efficient use of the polarization separation effect to achieve high efficiency, high luminance of illumination light, and high power consumption. An object of the present invention is to provide a polarized light illuminating device having low power.

[0007]

In order to achieve the above object, the first invention of the present application is to provide at least a light source and light from the light source from one side, and to make the incident light perpendicular to the one side. A light guide for guiding light between the upper surface and the lower surface parallel to each other, a reflector disposed on the lower surface side of the light guide to reflect light guide light, and a light guide disposed on the upper surface side of the light guide. In a polarized light illuminating device that transmits a component in a certain polarization direction in the light, and includes a polarization separation plate that reflects a component in a direction perpendicular to the certain polarization direction, the lower surface of the light guide includes the one side surface and A plurality of parallel V-shaped grooves are formed in parallel.

In such a configuration, light from a light source is incident from one side surface of the light guide, and the incident light is guided between the upper surface and the lower surface perpendicular to the one side surface and parallel to each other. The light guide light is reflected by the reflection plate arranged on the lower surface side of the light guide, and a component of a certain polarization direction in the light guide light is transmitted by the polarization separation plate arranged on the upper surface side of the light guide. When the component in the polarization direction and the component in the direction perpendicular to the light are reflected, the light guide light is scattered by the plurality of grooves having an inverted V-shaped cross section formed on the lower surface of the light guide in parallel with the one side surface. Even without the diffusion dots as in the conventional example, the reflected light from the polarization separation plate can be effectively used. Therefore, the problem that the light absorption by the diffusion dots increases due to multiple reflection between the light guide and the polarization separation plate is solved, the light efficiency is improved, the luminance of the illumination light is increased, and the power consumption is reduced. Becomes

In a second aspect of the present invention, at least a light source and light from the light source are incident from one side, and the incident light is guided between an upper surface and a lower surface perpendicular to the one side surface and parallel to each other. And a reflector disposed on the lower surface side of the light guide and reflecting the light guide light, and disposed on the upper surface side of the light guide and transmitting a component of a certain polarization direction in the light guide light, In a polarized light illuminating device provided with a polarized light separating plate that reflects a component in a certain polarization direction and a component in a direction perpendicular to the polarization direction, a polarized light for aligning the polarization direction of light from the light source between the light source and one side surface of the light guide. A direction adjusting means is provided.

[0010] In such a configuration, the light from the light source is incident on the light guide with its polarization direction being pre-aligned by the polarization direction adjusting means disposed between the light source and one side surface of the light guide. Therefore, multiple reflection between the light guide and the polarization separation plate is reduced, the light efficiency is improved, the brightness of the illumination light is increased, and
Power consumption can be reduced.

According to a third aspect of the present invention, at least a light source and light from the light source are incident from one side surface, and the incident light is guided between an upper surface and a lower surface perpendicular to the one side surface and parallel to each other. And a reflector disposed on the lower surface side of the light guide and reflecting the light guide light, and disposed on the upper surface side of the light guide and transmitting a component of a certain polarization direction in the light guide light, In a polarized light illuminating device provided with a polarizing plate that reflects or absorbs a component in a certain polarization direction and a component in a direction perpendicular to the polarization direction, between the light source and one side surface of the light guide, of the light from the light source, the light guide A component in a certain polarization direction obliquely at 45 degrees to the longitudinal direction is emitted toward the upper surface of the light guide, and a component in a direction perpendicular to the certain polarization direction is directed toward the lower surface of the light guide. Polarized light separating means for separating both components so as to emit light is provided. Than it is.

[0012] In such a configuration, of the light from the light source, the light from the light source is inclined at an angle of 45 degrees with respect to the longitudinal direction of the light guide by the polarization separating means disposed between the light source and one side of the light guide. A component in a certain polarization direction is emitted toward the upper surface of the light guide, and both components are previously set so that a component in a direction perpendicular to the component in the certain polarization direction is emitted toward the lower surface of the light guide. Since the light is separated and incident on the light guide, the multiple reflection between the light guide and the polarizing plate is also reduced in this case, the light efficiency is improved, and the illumination light can have higher brightness and lower power consumption. Becomes

In the first to third aspects of the present invention, the upper surface of the light guide may be a surface located on the lower side of the light guide or a side surface of the light guide depending on the arrangement of the device. Depending on the arrangement of the device, the lower surface of the light guide may be located on the upper surface of the light guide or on the side of the light guide. In some cases. For one side of the light guide and the other,
Similarly, it may be a surface located on the upper side of the light guide or a surface located on the lower side.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following embodiments are examples in which the present invention is embodied, and do not limit the technical scope of the present invention. This embodiment exemplifies a polarized light illumination device as shown in FIGS.

(First Embodiment) In a polarized light illuminating apparatus A1 according to a first embodiment, as shown in FIG. 1, at least a fluorescent lamp 1 as a light source and light from the fluorescent lamp 1 are reflected and collected. A reflective cover 2; and a light guide 3 that receives light condensed by the reflective cover 2 from one side surface 3a and guides the incident light between an upper surface 3d and a lower surface 3c that are perpendicular to the side surface 3a and parallel to each other. A reflection plate 5 disposed on the lower surface 3c side of the light guide 3 to diffuse light emitted downward from the light guide 3 and return to the light guide 3; and a reflection plate 5 disposed on the upper surface 3d side of the light guide 3. Light guide 3
A diffusion plate 6 for diffusing the light emitted upward from the light source, and a light having a certain polarization direction (P polarization) of the light emitted upward from the diffusion plate 6 and transmitting the light in a direction perpendicular to the polarization direction (S polarization). It is the same as the conventional example in that a polarization separation plate 7 that emits only P-polarized light upward by reflecting light is provided. However, this device A1 differs from the conventional example in that a plurality of grooves 8 having an inverted V-shaped cross section are formed in the lower surface 3c of the light guide 3 in parallel with the side surface 3a. The auxiliary reflection plate 4 reflects the light emitted from the other side surface 3b of the light guide 3 facing the side surface 3a, and
It is for returning to.

First, the basic principle of the operation of the apparatus A1 will be described. In FIG. 2, light emitted from the fluorescent lamp 1 is:
The light is directly incident on the light guide 3 like the light ray L 1, or is once reflected by the reflection cover 2 like the light ray L 2 before being incident on the light guide 3.

The light incident on the light guide 3 in this way is shown in FIG.
The light propagates through the light guide 3 as shown in FIG. Here the light guide 3
Let n be the refractive index of the incident light, this incident light is light having a radiation distribution of ± sin ^-1 (1 / n) according to the well-known Snell's rule. Most of the materials of the light guide 3 have a refractive index n of 1.42 or more, and thus this radiation distribution is within a range of ± 44.77 degrees.

The light guide 3 has an upper surface 3d and a lower surface 3c.
Are parallel, and the side surface 3a, which is the plane of incidence on the light guide 3, and the upper surface 3d and the lower surface 3c form an angle of 90 degrees, so that the side surface 3a
Is incident on the upper surface 3d or the lower surface 3c after propagating through the light guide 3, the minimum value of the incident angle becomes 45.
23 degrees (= 90-44.77). When the refractive index n is 1.
Since the total reflection angle at 42 or more is 44.77 degrees or less, light incident from the side surface 3a is totally reflected at the upper surface 3d or the lower surface 3c.

Of the light propagating in the light guide 3, a light ray L3
As described above, the light totally reflected by the flat portion 3c ′ other than the vicinity of the groove 8 propagates while being totally reflected in the light guide 3. On the other hand, light totally reflected by the flat portion 3c ″ near the groove portion 8 and totally reflected by the inclined surface 8a, like the light ray L4, is incident on the upper surface 3d by largely changing the optical path. Since the optical path is greatly changed by the two total reflections, the incident angle becomes equal to or smaller than the total reflection angle, and most of the light is emitted out of the light guide 3.

Light directly incident on the slope 8a, such as the light ray L5, is refracted on the slope 8a, transmitted between the slopes 8a and 5b, refracted on the slope 8b, returned to the light guide 3, and returned to the light guide 3. Body 3
It propagates while totally reflecting inside. As described above, the light propagating in the light guide 3 is emitted from the upper surface 3d of the light guide 3 by two total reflections at the flat portion 52 and the slope 53.

Next, the operation of the apparatus A1 will be described. In FIG. 4, light L <b> 4 propagating in the light guide 3 is emitted from the upper surface 3 d of the light guide 3 by total reflection in the groove 8 formed on the lower surface 3 c of the light guide 3. Since the light emitted from the fluorescent lamp 1 in FIG. 1 is generally random polarized light (P + S), the light emitted from the light guide 3 is also random polarized light (P + S). The light that has reached the polarization separation plate 7 is a P-polarized light L, which is a polarization component of the polarization separation plate 7 in the transmission axis direction.
6 is transmitted, and S-polarized light L7, which is a component orthogonal to the P-polarized light L6, is reflected. The S-polarized light L7 passes through the light guide 3,
The polarization is eliminated by the reflection plate 5, and the reflection light (P + S) L8 is obtained. When the reflected light (P + S) L8 reaches the polarization separation plate 7, the P-polarized light component L9 is transmitted, and the remaining S-polarized light component L10 is reflected, and the above operation is repeated.

As described above, according to the device A1, light from the light source is incident from one side of the light guide, and this incident light is perpendicular to the one side and parallel between the upper and lower surfaces. The light is guided, and the light guide is reflected by the reflector disposed on the lower surface side of the light guide. The component of a certain polarization direction in the light guide is reflected by the polarization separation plate disposed on the upper surface side of the light guide. Is transmitted, and when the component in the direction perpendicular to the certain polarization direction is reflected, the light guide light is formed on the lower surface of the light guide by a plurality of V-shaped cross-section grooves formed in parallel with the one side surface. Are scattered, so that the reflected light from the polarization separation plate can be effectively used without the diffusion dots as in the conventional example. Therefore, the problem that the light absorption by the diffusion dots increases due to multiple reflection between the light guide and the polarization separation plate is solved, the light efficiency is improved, the luminance of the illumination light is increased, and the power consumption is reduced. Becomes

(Embodiment 2) As shown in FIG. 5, a polarization illuminating device A2 according to Embodiment 2 has a different shape of the lower surface of the light guide from the device A1, but the other points are the same as those of the device A1. Is the same as In FIG. 5, the lower surface 13c of the light guide 13 of the device A2 has a step-like shape that rises from the side surface 13a to the side 13b, and the groove 1 is formed in a step portion of the step.
8 are formed. Therefore, the light guide 13 is wedge-shaped macroscopically, but its lower surface 13c forms a split plane parallel to the upper surface 13d.

According to the device A2, in addition to the same functions and effects as those of the device A1, the upper surface 1
The light propagating in parallel to the 3d and the lower surface 13c is also positively reflected in the direction of the upper surface 13d by the groove 18, so that it is less likely to directly escape from the side surface 13b. For this reason, the auxiliary reflector as in the device A1 can be omitted, and the device can be simplified. However, side 1
By providing an auxiliary reflection plate at 3b, the light collection efficiency can be further improved, and the luminance of the illumination light can be further increased.

(Embodiment 3) As shown in FIG. 6, a polarized light illuminating device A3 according to Embodiment 3 is reflected by the reflector 25 between the lower surface 23c of the light guide 23 and the reflector 25. A quarter-wave plate 29 for rotating the polarization direction of the light guide light by about 90 degrees is inserted, and the polarization direction of the light guide light is held further above the polarization separation plate 27 on the upper surface 23d side of the light guide 23. The device A1 is different from the device A1 in that a microlens array 30 for diffusing the emission direction is arranged, and the other points are the same as the device A1. However, in the present device A3, since the microlens array 30 is provided, the diffuser plate in the device A1 is unnecessary.

First, a microlens array which is one of the features of the present apparatus 3a will be described.

As shown in FIG. 7, the microlens array 30 is a lens in which lenses having a large aperture ratio and a small outer diameter are densely arranged on a plane. 6, the P-polarized light L11 emitted upward from the polarization separation plate 27 in FIG. 6 is once collected by the respective incident microlenses 30a to become diffused light L12. At this time, the micro lens 3
Since the polarization direction is maintained by the characteristic of Oa, it is possible to generate a wide-field emission light without eliminating polarization.

FIG. 8 shows a plan view of the microlens array 30 in the device A3. Although FIG. 2 shows an example in which micro lenses 30a of the same size are arranged, the size of each lens can be changed. Examples of a manufacturing method of such a microlens array 30 include a polishing method, a selective ion exchange method using a multi-component glass substrate, a photothermal method using a crystallized glass substrate, and an ion beam etching method using a Si substrate. Is applicable.

Next, the operation of the apparatus A3 will be described. In the present device A3, as shown in FIG. 6, the light emitted from the fluorescent lamp 21 is condensed by the reflection cover 22 on one side surface 23a of the light guide 23, and enters the light guide 23 from here. The incident light propagates through the light guide 23 within the critical angle, is sequentially reflected by the groove 28 formed on the lower surface 23c, and is emitted above the light guide 23.

That is, in FIG. 9, the light L13 propagating inside the light guide 23 is totally reflected by the groove 28 formed on the lower surface 23c of the light guide 23, and thus the light L13 is transmitted through the upper surface 2 of the light guide 23.
Released from 3d. Since the light emitted from the fluorescent lamp 21 in FIG. 6 is generally random polarized light (P + S), the light emitted from the light guide 23 is also random polarized light (P + S). Of the light L12 that has reached the polarization separation plate 27, the P-polarization light L14, which is a polarization component in the transmission axis direction of the polarization separation plate 27, is transmitted, and the S-polarization light L15, which is a component orthogonal to the P-polarization light L14, is reflected. . The P-polarized light L14 becomes the diffused light L16 by the microlens array 30 while maintaining its polarization direction. The S-polarized light L15 passes through the light guide 23, is converted into P-polarized light by the quarter-wave plate 29 and the reflecting plate 25, and is reflected to become reflected light L17. Since the reflected light L17 is P-polarized light, it passes through the polarization splitting plate 27 as it is, and becomes the diffused light L18 by the microlens array 30 while maintaining its polarization direction.

As described above, according to the present apparatus A3, in addition to the same operation and effect as the above-mentioned apparatus A1, the reflected light from the polarization splitting plate is further polarized by the quarter-wave plate and the reflecting plate. Is directly converted, so that multiple reflections between the light guide and the polarization splitter do not occur.

Therefore, the light efficiency is further improved, and the luminance of the illumination light can be further increased, and the power consumption can be further reduced.

In place of the microlens array 30, a microlens array 3 having a configuration as shown in FIG.
1 can also be used. In FIG. 10, 31a is a cylindrical lens constituted by a cylindrical surface,
According to the microlens array 31 in which the lenses 31a are arranged on a plane, the reflected light L17 in FIG. 9 diffuses in the x direction in the figure while maintaining the polarization direction, but does not diffuse in the y direction.

Further, a microlens array 32 having a structure as shown in FIG. 11 can be used. In FIG. 11, reference numerals 32a and 32b denote cylindrical lenses each having a cylindrical surface similar to the above-described 31a,
The micro lens array 32 includes the cylindrical lens 3
2a on a plane and a cylindrical lens 3
2b are arranged on a plane and superposed. Then, by making the generatrix of the cylindrical lens 32a and the cylindrical lens 32b orthogonal to each other,
The reflected light L17 in FIG. 9 is diffused in both the x and y directions in the figure while maintaining the polarization direction.

Further, a micro lens array 33 having a structure as shown in FIG. 12 can be used. In FIG. 12, reference numeral 33a denotes a groove having a V-shaped cross section which functions as a prism, and according to the microlens array 33 in which the grooves 33a are continuously arranged, the reflected light L17 in FIG. 9 maintains the polarization direction. Although it is diffused in the x direction in the drawing, it is not diffused in the y direction.

A microlens array 34 having a configuration as shown in FIG. 13 can be used. In FIG. 13, both 34a and 34b have the same V as the above 33a.
The micro-lens array 34 has a configuration in which a V-shaped groove 34a is continuously arranged and a V-shaped groove 34b is continuously arranged. . The V-shaped groove 34a and the V-shaped groove 3
4b, the reflected light L in FIG.
Numeral 17 diffuses in both the x and y directions in the figure while maintaining the polarization direction.

(Embodiment 4) As shown in FIG. 14, the polarization illuminator A4 according to Embodiment 4 has a different shape of the lower surface of the light guide from the above-described device A3. Is the same as

In FIG. 14, the light guide 43 of the device A4 is shown.
The lower surface 43c has a step-like shape that goes upward from the side surfaces 43a to 43b, and a groove 48 is formed at a step portion of the step. Therefore, the light guide 43 is wedge-shaped macroscopically, but its lower surface 43c forms a split plane parallel to the upper surface 43d.

According to the device A4, in addition to the same functions and effects as those of the device A3, the light guide 43 further includes an upper surface 4
3d, the light propagating in parallel with the lower surface 43c is also positively reflected in the direction of the upper surface 43d by the groove portion 48, so that it is less likely to directly escape from the side surface 43b. Therefore, the auxiliary reflector as in the device A1 can be omitted, and the device can be simplified. However, side 4
By providing an auxiliary reflection plate at 3b, the light collection efficiency can be further improved, and the luminance of the illumination light can be further increased.

In this apparatus A4, the apparatus A3
Similarly to the above, as the microlens array 50, a microlens array having any of the configurations shown in FIGS. 7, 8, and 10 to 13 can be used.

(Fifth Embodiment) As shown in FIG. 15, a polarized light illuminating device A5 according to a fifth embodiment is configured such that a component of a certain polarization direction in a light guide light is provided in a groove 58 of a lower surface 53c of a light guide 53. And a polarization separating film 58a for transmitting a component in a direction perpendicular to the certain polarization direction is formed, and the polarization of the light guide light is applied to the other side 53b opposite to one side 53a of the light guide 53. The device A1 or the device A1 described above in that a quarter-wave plate (corresponding to a second quarter-wave plate) 61 and a reflector (corresponding to a second reflector) 54 for rotating the direction by approximately 90 degrees are disposed. Different from the device A3. Other points are the same as above,
Common parts are omitted in the drawings, and detailed description thereof is omitted (the same applies to the following embodiments). As a method of forming the polarization separation film 58a in the groove 58 on the lower surface 53c of the light guide 53,
There are vapor deposition and sputtering.

In FIG. 15, the light emitted from the fluorescent lamp 51 is reflected by the side surface 53 a of the light guide 53 by the reflection cover 52.
And is incident on the light guide 53. The incident light propagates through the light guide 53 within the critical angle.

Next, the operation of the apparatus A5 will be described. In FIG. 16, of the light propagating in the light guide 53, the light incident on the inclined surface 58 b of the groove 58 like the light ray L <b> 51 is a polarization separation film which is formed in the groove 58 and performs a polarization separation operation. By the function of the film 58a, the P-polarized light L52, which is a polarization component parallel to the fluorescent lamp 51 in FIG. 15, is reflected and emitted upward, and the S-polarization light L53, which is a polarization component perpendicular to this, is refracted and transmitted. Flat part 5 like ray L54
The light totally reflected at 3c 'propagates through the light guide 53 by total reflection.

As shown in FIG. 17, while the light incident on the light guide 53 propagates through the light guide 53, the P-polarized light L55 is sequentially emitted upward by the plurality of groove portions 58, and S The polarized light L56 reaches the 波長 wavelength plate 61. S
The polarization direction of the polarized light L56 is changed by about 90 degrees by the quarter-wave plate 61 and the reflecting plate 54, and returns to the light guide 53 as P-polarized light L57. Of the P-polarized light L57, the light L5
When the light beam L55 hits the slope 58c of the groove portion 58 as shown in FIG. 5, the light ray L55 is reflected and emitted upward. Like the light ray L58, the light totally reflected by the flat portion 53c 'propagates in the light guide 53 by total reflection, and when reflected on the inclined surface 58b or 58c of the groove portion 58, is reflected and emitted upward.

That is, the returning P-polarized light L57 is sequentially emitted upward through the plurality of grooves 58 while propagating through the light guide 53.

As described above, according to the present apparatus A5, light having a certain polarization direction can be directly transmitted by using a light guide having a groove formed with a polarization separation film which is a multilayer film having a polarization separation effect. Since the light can be emitted upward, the light efficiency can be improved.

Thus, there is no occurrence of multiple reflection and no loss due to light absorption. Also, through the air layer,
Since there is no need to provide a polarizing plate, uncontrollable light due to surface reflection does not occur. Therefore, it is possible to further increase the luminance of the illumination light or reduce the power consumption.

The lower surface 53c of the light guide 53 of the device A5
Provided with a diffuse reflection plate as in the device A1,
The light efficiency can be improved by returning the light leaked from the groove 58 to the light guide 53.

(Sixth Embodiment) As shown in FIG. 18, a polarized light illuminating device A6 according to a sixth embodiment has a structure in which light from the fluorescent lamp 71 is provided between the fluorescent lamp 71 and one side surface 73a of the light guide 73. Device A1 or device A3 in that a polarization direction adjusting means 80 for aligning the polarization directions is arranged. That is, in FIG. 18, reference numeral 81 denotes a polarizing beam splitter, which transmits P-polarized light, which is a component in a certain polarization direction, of the light from the fluorescent lamp 71, and converts S-polarized light, which is a component in a direction perpendicular to this direction. reflect. A half-wave plate 82 rotates the polarization component of the light reflected by the polarization beam splitter 81 by approximately 90 degrees. Reference numeral 83 denotes a reflector (corresponding to a third reflector), which adjusts the direction of the reflected light from the polarizing beam splitter 81 to the direction of the transmitted light. These polarization beam splitters 81 and 1
The half-wave plate 82 and the reflection plate 83 constitute the polarization direction adjusting means 80.

First, the principle of operation of the polarization direction adjusting means 80, which is a feature of the apparatus A6, will be described. In FIG. 19, the light emitted from the fluorescent lamp 71 is generally random polarized light (P + S). Of the light L71 incident on the end of the polarization beam splitter 81, the P-polarized light L72 passes through the polarization beam splitter 81. On the other hand, the S-polarized light L73 is reflected, the polarization direction thereof is changed by approximately 90 degrees by the half-wave plate 82 to become the P-polarized light L74, and the P-polarized light L75 is reflected by the reflector 83. Lights L72 and L75 from these two paths are both P-polarized light. That is, when the randomly polarized light from the fluorescent lamp 71 is incident on the polarization direction adjusting unit 80, it becomes P-polarized light and is emitted from the polarization direction adjusting unit 80.

Next, the operation of the apparatus A6 will be described. In FIG. 18, light emitted from a fluorescent lamp 71 is condensed by a reflection cover 72 and is adjusted by a polarization direction adjusting unit 80.
Incident on. This incident light becomes P-polarized light by the polarization direction adjusting means 80 and enters the light guide 73. Light guide 7
The light incident on the light guide 3 propagates through the light guide 73 within the critical angle while maintaining its polarization direction, and is sequentially reflected by the groove 78 formed on the lower surface 73c and emitted above the light guide 73. Is done.

As described above, according to the present apparatus A6, the polarization direction of light from the light source is previously adjusted to P-polarized light by the polarization direction adjusting means disposed between the light source and one side surface of the light guide. Since the light enters the light guide, the light can be emitted directly upward by the light guide having a simple structure. Therefore, multiple reflection between the light guide and the polarization separation plate is reduced, and light efficiency is improved,
It is possible to increase the luminance of illumination light and reduce power consumption.

Incidentally, instead of the polarization beam splitter 81 of the polarization direction adjusting means 80, a polarization separation sheet 84 as shown in FIG. 20 may be used. This polarization separation sheet 84
Is obtained by forming a multilayer film having a polarization separation effect on a thin sheet. As a method of forming the multilayer film, there are vapor deposition, sputtering and the like. With such a polarization separation sheet 84,
A half-wave plate (corresponding to a second half-wave plate) 82a,
The same effect as that of the polarization direction adjusting means 80 can be obtained by the reflector (corresponding to the fourth reflector) 83a.

The reflection cover 72 and the reflection plate 83a may be integrated, and the reflection cover 85 shown in FIG. 21 is one example. Thus, the reflection cover 72 and the reflection plate 83a
By using the reflective cover 85 having both functions, the number of parts of the apparatus can be reduced.

Further, as shown in FIG. 22, by using a polarization separating sheet 84 instead of the polarization beam splitter 81 of the polarization direction adjusting means 80 and using a reflection cover 85 in which a reflection cover 72 and a reflection plate 83a are integrated. The same operation and effect as the polarization beam splitter 81 of the polarization direction adjusting means 80 can be obtained, and the number of parts of the apparatus can be reduced.

(Embodiment 7) As shown in FIG. 23, a polarization illuminating device A7 according to Embodiment 7 is different from the above-described device A6 in the shape of the lower surface of the light guide. Is the same as

In FIG. 23, the light guide 93 of the device A7 is shown.
The lower surface 93c has a step-like shape that goes upward from the side surfaces 93a to 93b, and a groove 98 is formed adjacent to a step portion of the step. Therefore, the light guide 93 is
Although it is macroscopically wedge-shaped, its lower surface 93c is
A division plane parallel to 3d is formed.

According to the device A7, in addition to the same functions and effects as those of the device A6, the upper surface 9
3d, the light propagating in parallel with the lower surface 93c is also positively reflected by the groove 98 in the direction of the upper surface 93d, so that the light is less likely to escape directly from the side surface 93b. For this reason, the auxiliary reflector as in the device A6 can be omitted, and the device can be simplified. However, side 9
By providing an auxiliary reflection plate at 3b, the light collection efficiency can be further improved, and the luminance of the illumination light can be further increased.

Note that, in the present apparatus A7, the apparatus A6
Similarly to the above, instead of the polarization beam splitter 101 of the polarization direction adjusting means 100, a polarization separation sheet as shown in FIGS.
May be used.

(Eighth Embodiment) As shown in FIG. 24, a polarized light illumination device A8 according to the eighth embodiment
Between the light guide 113 and the side surface 113 a of the light guide 111.
Direction adjusting means 1 for aligning the polarization direction of light from
20 is different from the above-mentioned device A1 or the above-mentioned device A3. That is, in FIG. 24, a polarizing beam splitter 121 transmits P-polarized light, which is a component in a certain polarization direction, of the light from the fluorescent lamp 111,
It reflects S-polarized light that is a component in a direction perpendicular to this. 12
Reference numeral 2 denotes a half-wave plate (corresponding to a third half-wave plate), which rotates the polarization component of light transmitted by the polarization beam splitter 121 by approximately 90 degrees. 122
Is a reflection plate (corresponding to a fourth reflection plate), which adjusts the direction of the reflected light from the polarizing beam splitter 121 to the direction of the transmitted light. These polarization beam splitters 121
, The half-wave plate 122 and the reflection plate 123 constitute the polarization direction adjusting means 120, and only the arrangement of the half-wave plate 122 is different from that of the device A6.

First, the principle of operation of the polarization direction adjusting means 120, which is a feature of the apparatus A8, will be described. In FIG. 25, light emitted from the fluorescent lamp 111 is generally random polarized light (P + S). Of the light L111 that has entered the end of the polarizing beam splitter 121, the P-polarized light L112 passes through the polarizing beam splitter 121 and
By means of 22, the polarization direction is changed by approximately 90 degrees to become S-polarized light L113.

On the other hand, of the incident light, the S-polarized light L114 is reflected and reflected by the reflector 123 to become the S-polarized light L115. Light L113, L115 by these two paths
Are both S-polarized lights. That is, when the randomly polarized light from the fluorescent lamp 111 enters the polarization direction adjusting unit 120, it becomes S-polarized light and exits from the polarization direction adjusting unit 120.

Next, the operation of the apparatus A8 will be described. In FIG. 24, the light emitted from the fluorescent lamp 111 is:
The light is condensed by the reflection cover 112 and enters the polarization direction adjusting means 120. This incident light is reflected by the polarization direction adjusting means 1.
The light 20 becomes S-polarized light and enters the light guide 1. The light incident on the light guide 113 propagates through the light guide 113 within the critical angle while maintaining its polarization direction.
The light is sequentially reflected and emitted above the light guide 113 by the groove 118 formed in 3c.

As described above, according to the present apparatus A8, the polarization direction of the light from the light source is previously adjusted to S-polarized light by the polarization direction adjusting means disposed between the light source and one side surface of the light guide. Although the light is incident on the light guide, the direction of polarization coincides with the direction of the inverted V-shaped groove on the lower surface of the light guide, so that the incident light can be emitted directly upward by the light guide having a simpler structure. . Therefore, the multiple reflection between the light guide and the polarization splitter is reduced, the light efficiency is improved, and the brightness of the illumination light and the power consumption can be reduced.

In place of the polarization beam splitter 121 of the polarization direction adjusting means 120, a polarization separation sheet (corresponding to a second polarization separation sheet) 124 as shown in FIG. 26 may be used. The polarized light separating sheet 124 is formed by forming a multilayer film having a polarized light separating effect on a thin sheet. As a method of forming the multilayer film, there are vapor deposition, sputtering and the like. The polarization direction adjusting means 120 is also provided by such a polarization separating sheet 124, a half-wave plate (corresponding to a third half-wave plate) 122a, and a reflector (corresponding to a sixth reflector) 123a. The same operation and effect as described above can be obtained.

The reflection cover 112 and the reflection plate 123a may be integrated, and the reflection cover 125 shown in FIG. 27 is one example. Thus, the reflection cover 112 and the reflection plate 1
By using the reflection cover 125 having the two functions 23a, the number of components of the apparatus can be reduced.

Further, as shown in FIG. 28, a polarization separating sheet 124 is used instead of the polarization beam splitter 121 of the polarization direction adjusting means 120, and a reflection cover 112 is used.
By using the reflection cover 125 in which the reflection cover 123a and the reflection plate 123a are integrated, the same operation and effect as the polarization beam splitter 121 of the polarization direction adjusting means 120 can be obtained, and the number of components of the apparatus can be reduced. it can.

(Embodiment 9) As shown in FIG. 29, the polarization illuminating device A9 according to Embodiment 9 differs from the device A8 in the shape of the lower surface of the light guide. Is the same as

In FIG. 29, the light guide 13 of the device A9
The lower surface 133c of Step 3 has a step-like shape that goes upward from the side surfaces 133a to 133b, and a groove 138 is formed at a step portion of the step. Therefore, the light guide 133
Is macroscopically wedge-shaped, but its lower surface 133c forms a split plane parallel to the upper surface 133d.

According to the device A9, in addition to the same function and effect as the device A8, the light propagating in the light guide 133 in parallel with the upper surface 133d and the lower surface 133c is also positively activated by the groove 138. Since the light is reflected in the direction of the upper surface 133d, it is less likely that the light is directly removed from the side surface 133b. For this reason, the auxiliary reflector as in the device A6 can be omitted, and the device can be simplified.
However, by providing an auxiliary reflector on the side surface 133b, the light collection efficiency can be further improved, and the luminance of the illumination light can be further increased.

In this apparatus A9, the apparatus A8
Similarly to the above, instead of the polarization beam splitter 141 of the polarization direction adjusting means 140, a polarization separation sheet as shown in FIGS.
3 may be used.

(Embodiment 10) A polarized light illuminating device A10 according to Embodiment 10 is arranged such that a light component from a light source and a component in a certain polarization direction are interposed between the light source and one side surface of the light guide. It differs from the above-mentioned devices A1 to A9 in that a polarization separation means for separating the component into a component in a direction perpendicular to the above component is provided. In FIG. 30, reference numeral 151 denotes a prism part constituting the above-mentioned polarized light separating means. The prism part 151 is made of quartz, glass, or a transparent resin (for example, an acrylic resin, polycarbonate, or the like). One surface 151a of the prism part 151 is an incident surface, and this incident surface 1
Non-polarized light enters from 51a. Reference numeral 152 denotes a polarization splitting surface. The polarization splitting surface 152 is disposed at an inclination angle of about 45 degrees with respect to the incident surface 151a, and the optical multilayer film (second
(Corresponding to a polarized light separating film). As an example of the optical multilayer film, there is known an optical multilayer film utilizing a reflection / transmission characteristic at a Brewster angle.

That is, when a parallel ray is incident on a transparent dielectric (refractive index n), the polarization component (S component) perpendicular to the incident surface becomes a Brewster angle, which is an angle satisfying tan θ = n as the incident angle θ. Although a part is reflected and another part is passed, the component (P component) parallel to the incident surface is not reflected but transmitted entirely. Therefore, the reflected light at this angle becomes completely S-polarized light and the transmitted light becomes partially polarized light with strong P-polarized light, so that a multilayer film in which a low-refractive-index film and a high-refractive-index film are alternately repeated is used. S-polarized light and P-polarized light can be almost completely separated. Reference numeral 153 denotes a reflection surface, which is formed of a metal film, a dielectric multilayer film, or the like. However, the reflection surface 153 may have the same composition as the polarization separation surface 152.

Next, the operation of the apparatus A10 will be described. In FIG. 30, light incident from the incident surface 151a reaches the polarization splitting surface 152. Here, the P-polarized light L1
51 passes and the S-polarized light L152 is reflected. Since the P-polarized light L151 passes through the polarization separation surface 152 from the prism unit 151 and exits into the air, the light beam direction changes due to refraction. On the other hand, the S-polarized light L152 is reflected by the multilayer film, and then exits from the exit surface 151b of the prism portion 151 into the air. However, since the exit surface 151b is perpendicular to the incident surface 151a, the change in the light beam direction due to refraction occurs. Is less.

The light emitted from the emission surface 151b is reflected by the reflection surface 153. The configuration of the reflection surface 153 is the polarization separation surface 1
Even if it is the same as 52, the light beam remains S-polarized light, so that it is reflected here as well as the reflection surface 153. Since the center light of the light beam is disposed at approximately 45 degrees with respect to the incident surface 151a, both the polarization separation surface 152 and the reflection surface 153 are emitted in a direction substantially parallel to the incident light beam. As a result, the incident non-polarized light can be separated into P-polarized light and S-polarized light having different emission angles.

As shown in FIG. 31, the light exit surface 161b
May be 90 degrees or less with respect to the incident surface 161a. At this time, the center light of the incident light is
1b, then the direction of the light reflected by the reflection surface 163 is the direction of the P-polarized light L16 transmitted through the polarization separation surface 162.
Incline in the direction opposite to the direction of 1. As a result, the incident non-polarized light can be separated into P-polarized light and S-polarized light having different emission angles.

Further, by arranging a plurality of polarized light separating means side by side to form a sheet, the size can be reduced.
Such a configuration, as shown in FIG. 32 or FIG.
A groove 170a or 180 is formed on a transparent substrate 170 or 180 having a plurality of triangular grooves 170a or 180a parallel to each other on a surface opposite to a surface on which light from a light source is incident.
This can be realized by forming a polarization separation film (corresponding to a third polarization separation film) 170b or 180b on the inclined surface in the same direction a. However, FIG. 32 is different from FIG. 31 in that the inclination angle φ of the exit surface 161b to the entrance surface 161a is about 4
FIG. 33 corresponds to FIG. 30 corresponding to the case of 5 degrees.

(Embodiment 11) The above-described devices A1 to A10 are particularly effective when used for an illumination device utilizing polarized light, for example, a backlight of a transmission type liquid crystal display device.
The polarization illuminating device A11 according to the eleventh embodiment is an example of the configuration, and is illustrated in FIG. In FIG. 34,
Reference numeral 191 denotes a light source, which is, for example, a fluorescent lamp such as a hot cathode tube or a cold cathode tube, and a light emitting diode arranged in a line.
An incandescent lamp or an organic light emitting material formed linearly is disposed on the side surface of the light guide 193.

The reflectors 192 are arranged so as to cover the light source 191, and the inner surface thereof is configured to have a high reflectance and a low diffusivity. The light guide 193 has a plurality of grooves 198 as in the devices A1 to A10, and light incident from a light source is polarized by the grooves 198 to illuminate the liquid crystal display device 200.

Here, the polarization separation sheet 210 is disposed between the light guide 193 and the light source 191. Polarizing plate 19
7 is disposed on the upper surface of the light guide 193, and as shown in FIG.
It is arranged to be at 5 degrees. Liquid crystal display device 200
Is disposed above the polarizing plate 197.

In this device A11, the devices A1 to A1
A polarized light that transmits a component in a certain polarization direction (P-polarized light) in the light-guided light and reflects or absorbs a component in a direction perpendicular to the certain polarization direction (S-polarized light) instead of the polarization separation plate in A10. The plate 197 is used, and the lower surface 19 of the light guide 193 is used.
The liquid crystal display device 200 can be seen from the lower surface 193c without providing a reflector on 3c. Polarizing plate 1
97 may be a commercial product.

Next, the operation of the apparatus A11 will be described. In FIG. 34, the light emitted from the light source 191 is:
When passing through the polarization separation sheet 210, the light is separated into P-polarized light and S-polarized light, and enters the light guide 193 from the side surface 193 a of the light guide 193. The P-polarized light is on the upper surface 1 of the light guide 193.
The light travels toward 93d, and the S-polarized light travels toward the lower surface 193c of the light guide 193. As described above, since the P-polarized light travels toward the upper surface 193d of the light guide 193, as shown in FIG. 36, the polarization direction of the P-polarized light with respect to the upper surface 193d of the light guide 193 is the same as that of the polarizing plate 197 in FIGS. It is the same as the polarization direction.

On the other hand, the S-polarized light is applied to the lower surface 19 of the light guide 193.
3c, the light is reflected by the lower surface 193c and is reflected by the light guide 193.
34, the polarization direction of the light guide 193 with respect to the upper surface 193d is the same as the polarization direction of the polarizing plate 197 in FIGS.

Therefore, according to the present apparatus A11,
All the light that has used only one of the P-polarized light and the S-polarized light can be used by arranging the polarization separation sheet 210 on the side surface 193a of the light guide 193 as described above. Therefore, the luminance at the time of illumination, that is, the illumination intensity is doubled as compared with the related art.

In the devices A1 to A11, the upper surface of the light guide may be located on the lower surface of the light guide or on the side of the light guide depending on the arrangement of the device. Depending on the arrangement of the device, the lower surface of the light guide may be the surface located on the upper side of the light guide, or the surface located on the side surface of the light guide. May be possible. For one side of the light guide and the other,
Similarly, it may be a surface located on the upper side of the light guide or a surface located on the lower side.

The same effects as described above can be obtained by using the present invention in a reflection type liquid crystal display device instead of the transmission type liquid crystal display device. In this case, as in the case of the apparatus A11, the illumination intensity is reduced to the conventional value of 2.
Double. Further, there is an effect that there is no influence on the reflection type liquid crystal display device at the time of non-illumination.

[0087]

As is apparent from the above description, according to the present invention, the reflected light from the polarized light separating plate can be effectively used without the diffusion dots as in the conventional example. Therefore, the problem that the light absorption by the diffusion dots increases due to multiple reflection between the light guide and the polarization separation plate is solved, the light efficiency is improved, the luminance of the illumination light is increased, and the power consumption is reduced. Becomes

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional structure diagram of a polarized light illumination device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing how light propagates from a light source to a light guide.

FIG. 3 is an explanatory diagram showing how light propagates in a light guide.

FIG. 4 is an operation explanatory diagram of the polarized light illuminating device according to the first embodiment of the present invention;

FIG. 5 is a schematic sectional structural view of a polarized light illuminating device according to a second embodiment of the present invention.

FIG. 6 is a schematic sectional structural view of a polarized light illuminating device according to a third embodiment of the present invention.

FIG. 7 is an optical path diagram using a microlens array.

FIG. 8 is a plan view of a microlens array.

FIG. 9 is an operation explanatory diagram of the polarized light illumination device according to the third embodiment of the present invention;

FIG. 10 is a perspective view of a microlens array.

FIG. 11 is a perspective view of a microlens array.

FIG. 12 is a perspective view of a microlens array.

FIG. 13 is a perspective view of a microlens array.

FIG. 14 is a schematic sectional structural view of a polarized light illuminating device according to a fourth embodiment of the present invention.

FIG. 15 is a schematic sectional structural view of a polarized light illuminating device according to a fifth embodiment of the present invention.

FIG. 16 is an operation explanatory diagram of the polarized light illuminating device according to the fifth embodiment of the present invention;

FIG. 17 is an operation explanatory diagram of the polarized light illuminating device according to the fifth embodiment of the present invention;

FIG. 18 is a schematic sectional structural view of a polarized light illuminating device according to a sixth embodiment of the present invention.

FIG. 19 is an explanatory diagram showing how light of a polarization direction adjusting unit propagates.

FIG. 20 is a schematic sectional structural view of a polarization direction adjusting unit.

FIG. 21 is a schematic sectional structural view of a polarization direction adjusting unit.

FIG. 22 is a schematic sectional structural view of a polarization direction adjusting unit.

FIG. 23 is a schematic sectional structural view of a polarized light illuminating device according to a seventh embodiment of the present invention.

FIG. 24 is a schematic sectional structural view of a polarized light illuminating apparatus according to an eighth embodiment of the present invention.

FIG. 25 is an operation explanatory view of the polarized light illuminating device according to the eighth embodiment of the present invention;

FIG. 26 is a schematic sectional structural view of a polarization direction adjusting unit.

FIG. 27 is a schematic sectional structural view of a polarization direction adjusting unit.

FIG. 28 is a schematic sectional structural view of a polarization direction adjusting unit.

FIG. 29 is a schematic sectional structural view of a polarized light illuminating device according to a ninth embodiment of the present invention.

FIG. 30 is a schematic cross-sectional structure diagram of a polarization separation unit.

FIG. 31 is a schematic cross-sectional structure diagram of a polarization separation unit.

FIG. 32 is a schematic cross-sectional structure diagram of a polarization separation unit.

FIG. 33 is a schematic sectional structural view of a polarized light separating means.

FIG. 34 is a schematic sectional structural view of a polarized light illuminating apparatus according to an eleventh embodiment of the present invention.

FIG. 35 is a schematic layout diagram of a polarization separating sheet and a polarizing plate with respect to a light guide.

FIG. 36 is an operation explanatory view of the polarized light illuminating device according to the eleventh embodiment of the present invention.

FIG. 37 is an operation explanatory diagram of the polarized light illuminating device according to the eleventh embodiment of the present invention;

FIG. 38 is a schematic sectional structural view of an example of a conventional polarized light illumination device.

[Explanation of symbols]

A1 to A11 Polarized illumination device 1, 11, 21, 41, 51, 71, 91, 111, 1
31,191 Fluorescent lamp (power supply) 2,12,22,42,52,72,92,112,1
32, 192 Reflective cover 3, 13, 23, 43, 53, 73, 93, 113, 1
33,193 Light guide 4,24,54,74,114 Auxiliary reflector 5,15,25,45 Reflector 6,16 Diffuser 7,17,27,47 Polarization separator 197 Polarizer 8,18,28 , 48, 58, 78, 98, 118, 1
38, 198 Grooves 29, 49, 61 Quarter-wave plate 30-34, 50 Microlens array 58a Polarization separation film 80, 100, 120, 140 Polarization direction adjusting means 81, 101, 121, 141 Polarization beam splitters 82, 102 , 122, 142 1/2 wavelength plate 83, 103, 123, 143 Reflector 84, 124, 210 Polarization separation sheet 151, 161 Prism

Claims (16)

[Claims] At least a light source, light from the light source incident from one side surface, and a light guide for guiding the incident light between an upper surface and a lower surface perpendicular to the one side surface and parallel to each other; A reflection plate disposed on the lower surface side of the light body to reflect the light guide light; A polarized light illuminating device provided with a polarization separation plate that reflects a component in a direction perpendicular to the polarization direction, wherein a plurality of grooves each having an inverted V-shaped cross section are formed on a lower surface of the light guide in parallel with the one side surface. Lighting equipment. 2. The method according to claim 1, further comprising inserting a quarter-wave plate between the lower surface of the light guide and the reflector to rotate the polarization direction of the light guided by the reflector by approximately 90 degrees. Polarized lighting device. 3. A microlens array for diffusing an emission direction of a light guide light while maintaining a polarization direction of the light guide light is further provided on an upper surface of the polarization separation plate on an upper surface side of the light guide. Or the polarized light illumination device according to 2. 4. A polarization separating film that reflects a component in a certain polarization direction in the light guide light and transmits a component in a direction perpendicular to the certain polarization direction is formed in the groove on the lower surface of the light guide. The polarized light illuminating device according to claim 1. 5. A second quarter-wave plate and a second reflection plate for rotating the polarization direction of the light guide light by approximately 90 degrees on another side surface opposite to one side surface of the light guide. The polarized light illumination device according to claim 1, wherein the polarized light illumination device is arranged. 6. A light guide that receives at least a light source, light from the light source from one side surface, and guides the incident light between an upper surface and a lower surface perpendicular to the one side surface and parallel to each other; A reflection plate disposed on the lower surface side of the light body and reflecting the light guide light; and a reflection plate disposed on the upper surface side of the light guide and transmitting a component in a certain polarization direction in the light guide light, and a component in the certain polarization direction A polarization illuminating device provided with a polarization separation plate that reflects a component in a direction perpendicular to the light source, wherein a polarization direction adjusting means for aligning the polarization direction of light from the light source is arranged between the light source and one side surface of the light guide. A polarized lighting device, comprising: 7. The polarization direction adjusting means transmits a component in a certain polarization direction in the light from the light source and enters one side surface of the light guide, and a component in a direction perpendicular to the certain polarization direction component. A polarizing beam splitter for reflecting light, a half-wave plate for rotating the polarization direction of a component reflected by the polarizing beam splitter by approximately 90 degrees and entering one side surface of the light guide, and a third wavelength plate. 7. The polarized light illuminating device according to claim 6, comprising a reflector. 8. The polarization direction adjusting means transmits a component in a certain polarization direction in the light from the light source and enters one side surface of the light guide, and a component in a direction perpendicular to the certain polarization direction. And a second half for rotating the polarization direction of the component reflected by the polarization separation sheet by approximately 90 degrees to enter one side surface of the light guide.
7. The polarized light illuminating device according to claim 6, comprising a wave plate and a fourth reflector. 9. A second polarization beam splitter for transmitting a component in a certain polarization direction in light from the light source and reflecting a component in a direction perpendicular to the certain polarization direction in the light from the light source. A third half-wave plate for rotating the polarization direction of the component transmitted by the second polarization beam splitter by approximately 90 degrees to enter one side surface of the light guide; The polarization illuminating device according to claim 6, further comprising a fifth reflector for allowing the component reflected by the polarization beam splitter to enter one side surface of the light guide. 10. A second polarization separation sheet for transmitting a component in a certain polarization direction in light from the light source and reflecting a component in a direction perpendicular to the certain polarization direction in the light from the light source. A third half-wave plate for rotating the polarization direction of the component transmitted by the second polarization splitting sheet by approximately 90 degrees to enter one side surface of the light guide; and 7. The polarized light illuminating device according to claim 6, comprising a sixth reflector for allowing the component reflected by the polarized light separating sheet to enter one side surface of the light guide. 11. At least a light source, a light guide that receives light from the light source from one side surface, and guides the incident light between an upper surface and a lower surface perpendicular to the one side surface and parallel to each other; In a polarized light illuminating device including a polarizing plate disposed on the upper surface side of the light body and transmitting a component in a certain polarization direction in the light guide light and reflecting or absorbing a component in a direction perpendicular to the certain polarization direction, Between the light source and one side surface of the light guide, of the light from the light source, a component in a polarization direction having a direction approximately 45 degrees oblique to the longitudinal direction of the light guide is directed toward the upper surface of the light guide. And a polarized light separating means for separating both components in a direction perpendicular to the certain polarization direction toward the lower surface of the light guide. 12. The polarized light illuminating device according to claim 11, wherein a plurality of grooves having an inverted V-shaped cross section are formed in a lower surface of the light guide in parallel with the one side surface. 13. The polarized light separating means transmits a component in a certain polarization direction in the light from the light source and enters one side surface of the light guide. A triangular prism having one surface on which a second polarization splitting film for reflection is formed, and a component reflected by the second polarization splitting film of the triangular prism are converted into a second component of the triangular prism.
13. The polarized light illuminating device according to claim 11, further comprising a seventh reflector for entering one side surface of the light guide at an angle different from a component transmitted through the polarized light separating film. 14. The polarization separation means forms a plurality of triangular grooves parallel to each other on a surface opposite to a surface on which light from the light source is incident, and forms a third surface on the inclined surface of the grooves in the same direction. 13. The polarized light illuminating device according to claim 11, comprising a transparent substrate on which a polarized light separating film is formed. 15. The polarized light illuminating device according to claim 13, wherein one surface of the prism on which the second polarization splitting film is formed is disposed at a direction substantially 45 degrees with respect to the incident direction of light from the light source. 16. The polarized light according to claim 14, wherein the slopes of the grooves of the transparent substrate on which the third polarization splitting film is formed are disposed at approximately 45 degrees with respect to the incident direction of the light from the light source. Lighting equipment.