Display device and illumination device

According to one embodiment, a display device includes a display panel and an illumination device. The illumination device includes a light source unit, at least one light-shielding body which blocks part of the light emitted from the light source unit, at least one lens which refracts the light emitted from the light source unit, and an illumination controller. The illumination controller controls a first mode in which the light-shielding body and the lens are arranged at a first position, and a second mode in which at least one of the light-shielding body and the lens is arranged at a second position, which is different from the first position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2017-032077, filed Feb. 23, 2017, the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a display device and an illumination device.

BACKGROUND

For example, a light source device comprising a light control sheet which emits incident light at a predetermined output angle, and a liquid crystal display device including such a light source device have been proposed. The light control sheet includes a plurality of prisms arranged such that their generatrices are parallel to each other. Further, there has been proposed a liquid crystal display panel comprising a diffusion liquid crystal panel which diffuses linearly polarized light, oscillating in a predetermined direction, of light having directivity in a specific direction. The diffusion liquid crystal panel is configured to form a plurality of liquid crystal micro-lens portions by applying a voltage to transparent electrodes arranged with a liquid crystal layer interposed therebetween.

DETAILED DESCRIPTION

In general, according to one embodiment, a display device includes: a display panel; and an illumination device which illuminates the display panel, the illumination device including a light source unit which emits light toward the display panel, at least one light-shielding body which is located between the light source unit and the display panel, and blocks part of the light emitted from the light source unit, at least one lens which is located between the light source unit and the display panel, and refracts the light emitted from the light source unit, and an illumination controller, the illumination controller controlling a first mode in which the light-shielding body and the lens are arranged at a first position, and a second mode in which at least one of the light-shielding body and the lens is arranged at a second position, which is different from the first position.

According to another embodiment, an illumination device includes: a light source unit which emits light; a light-shielding body which blocks part of the light emitted from the light source unit; a lens which refracts the light emitted from the light source unit; and an illumination controller which controls a first mode in which the light-shielding body and the lens are arranged at a first position, and a second mode in which at least one of the light-shielding body and the lens is arranged at a second position, which is different from the first position.

According to yet another embodiment, an illumination device includes: a light source unit which emits light; a first light control body which controls an output angle of light emitted from the light source unit; a second light control body which controls an output angle of the light controlled by the first light control body; and an illumination controller which controls a first mode in which the first light control body and the second light control body are arranged at a first position, and a second mode in which at least one of the first light control body and the second light control body is arranged at a second position, which is different from the first position.

Embodiments will be described hereinafter with reference to the accompanying drawings. The disclosure is merely an example, and proper changes within the spirit of the invention, which are easily conceivable by a skilled person, are included in the scope of the invention as a matter of course. In addition, in some cases, in order to make the description clearer, the widths, thicknesses, shapes, etc., of the respective parts are illustrated in the drawings schematically, rather than as an accurate representation of what is implemented. However, such schematic illustration is merely exemplary, and in no way restricts the interpretation of the invention. In addition, in the specification and drawings, structural elements which function in the same or a similar manner to those described in connection with preceding drawings are denoted by like reference numbers, and redundant detailed description thereof is omitted unless necessary.

FIG. 1is an illustration showing a configuration example of a display device DSP of the present embodiment. While a first direction X, a second direction Y, and a third direction Z in the drawing are orthogonal to each other, they may cross each other at an angle other than 90 degrees. The third direction Z corresponds to a direction of arrangement of optical elements which constitute the display device DSP.

The display device DSP comprises a display panel1and an illumination device2which illuminates the display panel1. Although the details of the display panel1will be described later, in one example, the display panel1is a liquid crystal display panel.

The illumination device2comprises a light source unit3, a light-shielding body4, a lens5, and a controller6. The light source unit3emits light toward the display panel1. Although the details of the light source unit3will not be described here, the light source unit3may be, for example, an edge-light-type device comprising a plate-like light-guide arranged directly under the display panel1and a light source arranged along an edge of the light-guide, or may be a direct-type device comprising a light source arranged directly under the display panel1. Light emitted from the light source unit3does not necessarily have directivity in a particular direction. In the example illustrated, the light emitted from the light source unit3has diverging properties as shown by a plurality of arrows in the drawing.

The light-shielding body4and the lens5are located between the light source unit3and the display panel1. In the example illustrated, while the light-shielding body4is located between the light source unit3and the lens5, it may be located between the lens5and the display panel1. The light-shielding body4blocks part of the light emitted from the light source unit3. A plurality of light-shielding bodies4are arranged at intervals in the first direction X, for example. Each of the light-shielding body4has width W4in the first direction X, and extends in the second direction Y. The lens5refracts light emitted from the light source unit3. A plurality of lenses5are arranged at intervals in the first direction X, for example. Each of the lenses5has width W5in the first direction X, and extends in the second direction Y. A direction in which the light-shielding bodies4are arranged is the same as a direction in which the lenses5are arranged. Pitch P4between the light-shielding bodies4is less than or equal to pitch P5between the lenses5. The light-shielding body4and the lens5are both an example of a light control body which controls an output angle of light. Note that the light-shielding body4may be fixed to a predetermined position, or may be provided in a liquid crystal element40which will be described in detail later. Also, the lens5may be fixed to a predetermined position, or may be provided in a liquid crystal element50which will be described in detail later.

The controller6comprises a display controller7and an illumination controller8. The display controller7controls the display panel1. The illumination controller8controls the illumination device2.

FIG. 2is an illustration for explaining an example of control by the illumination controller8.FIG. 2(a)is an illustration for explaining a first mode which is controlled by the illumination controller8, andFIG. 2(b)is an illustration for explaining a second mode which is controlled by the illumination controller8.

In the first mode shown inFIG. 2(a), each of light-shielding bodies4A and4B, and the lens5is arranged at a first position P1. In the example illustrated, the light-shielding bodies4A and4B are arranged in the first direction X with a gap G4therebetween. The lens5is arranged such that a center50of the lens5and a center GO of the gap G4are positioned on a normal N of the light source unit3.

In such a first mode, of the light emitted from the light source unit3, while emitted light traveling in a direction parallel to the normal N and emitted light traveling in a direction slightly inclined with respect to the normal N pass through the gap G4, emitted light traveling in a direction greatly inclined with respect to the normal N is blocked by the light-shielding bodies4A and4B. In other words, the light-shielding bodies4A and4B allow only the light emitted in a direction close to a direction along the normal N to be passed through, of the divergent light. The lens5refracts the light which has passed through the gap G4. An emitting direction of light emitted from the illumination device2in the first mode falls within a range that is symmetrical with respect to the normal N. When a range of the emitting direction is assumed as a range of ±θ1with respect to the normal N, θ1is 30° in one example. Here, it is assumed that an angle formed by an inclination to the right in the drawing with respect to the normal N is positive (+), and an angle formed by an inclination to the left in the drawing with respect to the normal N is negative (−). In this first mode, when the illumination device2is observed in a direction opposite to a direction indicated by an arrow representing the third direction Z, the emitted light can be observed over an angular range that is symmetrical about the normal N. In one example, by reducing a width of the gap G4along the first direction X (or making the pitch between the light-shielding bodies4A and4B smaller than the pitch between the lenses5), a range of the emitting direction can be set to a smaller range of angle.

In the second mode shown inFIG. 2(b), while the light-shielding bodies4A and4B are arranged at the first position P1, the lens5is arranged at a second position P2. The second position in this mode is a position shifted to the right in the drawing along the first direction X as compared to the first position P1shown inFIG. 2(a). Alternatively, in the second mode, the light-shielding bodies4A and4B may be arranged at the second position P2while the lens5is arranged at the first position P1, or the light-shielding bodies4A and4B and the lens5may all be arranged at the second position different from the first position P1. As in the first mode, the light-shielding bodies4A and4B are arranged in the first direction X with the gap G4therebetween. The lens5is arranged such that the center50of the lens5is displaced from the center GO of the gap G4.

In such a second mode, the light-shielding bodies4A and4B allow only the light emitted in a direction close to the direction along the normal N to be passed through, as in the case of the first mode. The lens5refracts the light which has passed through the gap04. An emitting direction of light emitted from the illumination device2in the second mode falls within a range that is unsymmetrical with respect to the normal N. When a range of the emitting direction is assumed as a range of +θ2and −θ3with respect to the normal N, θ2is greater than θ3. In one example, θ2is 60° and θ3is 0°. In such a second mode, when the illumination device2is observed, the emitted light can be observed over an angular range that is unsymmetrical about the normal N in the first direction X. As described above, by changing a relative positional relationship between a place where the light-shielding bodies4A and4B are provided or the gap G4and the lens5along the first direction X, an angular range of the emitting direction can be controlled within an X-Z plane defined by the first direction X and the third direction Z.

FIG. 3is an illustration for explaining an example of control in another configuration example of the illumination device2.FIG. 3(a)is an illustration for explaining a first mode, andFIG. 3(b)is an illustration for explaining a second mode. Another configuration example shown inFIG. 3is different from the configuration example illustrated inFIG. 2in that the lens5is located between the light source unit3and the light-shielding bodies4A and4B.

In the first mode shown inFIG. 3(a), each of the light-shielding bodies4A and4B, and the lens5is arranged at the first position P1. The emitted light from the light source unit3is refracted by the lens5. Of the light refracted by the lens5, part of the light is blocked by the light-shielding bodies4A and4B. An emitting direction of light emitted from the illumination device2in the first mode falls within a range that is symmetrical with respect to the normal N.

In the second mode shown inFIG. 3(b), while the light-shielding bodies4A and4B are arranged at the first position P1, the lens5is arranged at the second position P2. Note that in the second mode, it suffices that at least either of the light-shielding body and the lens, i.e., the light-shielding bodies4A and4B and the lens5, is arranged at the second position different from the first position P1. In the second mode, the emitted light from the light source unit3is refracted by the lens5, and part of the refracted light is blocked by the light-shielding bodies4A and4B. An emitting direction of light emitted from the illumination device2in the second mode falls within a range that is unsymmetrical with respect to the normal N.

According to the present embodiment, by changing a relative positional relationship between a place where the light-shielding bodies4A and4B are provided or the gap G4and the lens5, the emitting direction of light emitted from the light source unit3can be controlled. Also, even if the light emitted from the light source unit3is greatly divergent, the emitting direction can be narrowed to a predetermined angular range, and directivity can be given to light.

Next, the liquid crystal element50comprising the lens5will be described. The liquid crystal element50corresponds to a first liquid crystal element.

FIG. 4is a cross-sectional view showing a configuration example of the liquid crystal element50.

The liquid crystal element50comprises a first substrate51, a second substrate52, a first liquid crystal layer53, a first control electrode E1, and a second control electrode E2. In the example illustrated, the first control electrode E1is provided on the first substrate51, and the second control electrode E2is provided on the second substrate52. However, the first control electrode E1and the second control electrode E2may both be provided on the same substrate, that is, on the first substrate51or the second substrate52.

The first substrate51comprises an insulating substrate511, a plurality of first control electrodes E1, an alignment film512, and a feeder513. The first control electrode E1is located between the insulating substrate511and the first liquid crystal layer53. The first control electrodes E1are arranged at intervals in the first direction X in an effective area50A. In one example, a width of each of the first control electrodes E1along the first direction X is less than or equal to an interval between adjacent first control electrodes E1along the first direction X. The alignment film512covers the first control electrodes E1, and is in contact with the first liquid crystal layer53. The feeder513is located in a non-effective area50B outside the effective area50A.

The second substrate52comprises an insulating substrate521, the second control electrode E2, and an alignment film522. The second control electrode E2is located between the insulating substrate521and the first liquid crystal layer53. The second control electrode E2is, for example, a single plate electrode which is located on substantially the entire surface of the effective area50A, and also extends to the non-effective area50B. The second control electrode E2is opposed to the first control electrode E1via the first liquid crystal layer53in the effective area50A. The second control electrode E2is opposed to the feeder513in the non-effective area50B. The alignment film522covers the second control electrode E2, and is in contact with the first liquid crystal layer53.

Each of the insulating substrates511and521is, for example, a glass substrate or a resin substrate. Each of the first control electrode E1and the second control electrode E2is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). Each of the alignment films512and522is, for example, a horizontal alignment film, and is subjected to alignment treatment in the first direction X.

The first substrate51and the second substrate52are bonded to each other by a sealant54in the non-effective area50B. The sealant54includes a conductive material55. The conductive material55is interposed between the feeder513and the second control electrode E2, and electrically connects the feeder513and the second control electrode E2.

The first liquid crystal layer53is held between the first substrate51and the second substrate52. The first liquid crystal layer53is formed of, for example, a liquid crystal material having positive dielectric anisotropy. The first control electrode E1and the second control electrode E2apply, to the first liquid crystal layer53, a voltage for forming the lens5in the first liquid crystal layer53.

The illumination controller8controls the voltage to be applied to the first liquid crystal layer53. By controlling the voltage to be applied to each of the first control electrode E1and the second control electrode E2, the illumination controller8can switch a mode between a mode in which the lens5is formed in the first liquid crystal layer53and a mode in which a lens is not formed in the first liquid crystal layer53. Further, by controlling the voltage to be applied to each of the first control electrodes E1, the illumination controller8can control a position where the lens5is formed. More specifically, the illumination controller8can form the lens5at each of the first position P1and the second position P2, as has been explained with reference toFIGS. 2 and 3. Furthermore, by controlling the voltage to be applied to each of the first control electrodes E1, the illumination controller8can control the size and the shape of the lens5freely.

FIG. 5is a plan view showing a configuration example of the liquid crystal element50.FIG. 5(a)is a plan view of the first substrate51, andFIG. 5(b)is a plan view of the second substrate52.

In the first substrate51shown inFIG. 5(a), the sealant54is formed in a frame shape. The first control electrodes E1are located at an inner side surrounded by the sealant54, and are arranged at intervals in the first direction X. Each of the first control electrodes E1is, for example, a strip electrode extending in the second direction Y. Alternatively, the first control electrodes E1may each be a strip electrode extending in the first direction X, or may be island-shaped electrodes arranged in the first direction X and the second direction Y. The shape of the island-shaped electrode is polygonal, such as rectangular or hexagonal, or circular. The feeder513extends in the second direction Y at a position overlapping the sealant54. At least a part of the conductive material55included in the sealant54overlaps the feeder513. A wiring substrate9is connected to the first substrate51, and electrically connects each of the first control electrodes E1and the feeder513with the illumination controller8.

In the second substrate52shown inFIG. 5(b), the second control electrode E2is formed rectangular, and includes an end portion E2E extending in the second direction Y. The end portion E2E overlaps the feeder513and the conductive material55. That is, the second control electrode E2is electrically connected to the illumination controller8via the conductive material55and the feeder513.

FIG. 6is an illustration for explaining the lens5formed in the first liquid crystal layer53.FIG. 6illustrates only the structures necessary for explanation. Here, a case of applying a voltage, which is different from that applied to first control electrode E11and E12, to the second control electrode E2will be described.

In one example, as described above, the first liquid crystal layer53has positive dielectric anisotropy. Liquid crystal molecules53M included in the first liquid crystal layer53are initially aligned such that their major axes are aligned in the first direction X in a state where an electric field is not formed, and are aligned such that the major axes of the liquid crystal molecules53M are aligned along an electric field in a state where the electric field is formed.

In one example, a voltage of 6V is applied to the first control electrode E11, a voltage of −6V is applied to the first control electrode E12, and a voltage of 0V is applied to the second control electrode E2. In regions in which the first control electrodes E11and E12are opposed to the second control electrode E2, an electric field along the third direction Z is formed. Therefore, the liquid crystal molecules53M are aligned such that their major axes are aligned along the third direction Z. In a region between the first control electrode E11and the first control electrode E12, an electric field which is tilted with respect to the third direction Z is formed. Therefore, the liquid crystal molecules53M are aligned such that their major axes are tilted with respect to the third direction Z. In an intermediate region, which is a region intermediate between the first control electrode E11and the first control electrode E12, an electric field is hardly formed or an electric field along the first direction X is formed. Therefore, the liquid crystal molecules53M are aligned such that their major axes are aligned along the first direction X. The liquid crystal molecule53M has refractive anisotropy Δn. Accordingly, the liquid crystal layer53has a refractive-index distribution according to an alignment state of the liquid crystal molecules53M. In other words, the liquid crystal layer53has a retardation distribution or a phase distribution which is represented by Δn·d, where d is a thickness of the first liquid crystal layer53along the third direction Z. Thickness d is, for example, 10 to 100 μm. The lens5shown by a dotted line in the drawing is one that is formed by the refractive-index distribution, retardation distribution, or phase distribution described above. The illustrated lens5functions as a convex lens.

In the present embodiment, a system formed by combining the first liquid crystal layer53including liquid crystal molecules which are initially aligned substantially horizontally along a substrate main surface and an electric field formed along a direction intersecting the substrate main surface has been explained, as an example of the liquid crystal element50comprising the lens5. However, the liquid crystal element50comprising the lens5is not limited to the above. For example, a liquid crystal layer including liquid crystal molecules which are initially aligned substantially perpendicularly to the substrate main surface may be combined, or the first liquid crystal layer53may be combined with an electric field formed along the substrate main surface. In other words, as long as the system can vary the refractive-index distribution according to an electric field applied to the liquid crystal layer, a liquid crystal element comprising the lens5can be realized. The substrate main surface mentioned above refers to an X-Y plane defined by the first direction X and the second direction Y.

FIG. 7is an illustration for explaining the function of the lens5illustrated inFIG. 6.

Here, when a traveling direction of light is along the third direction Z, linearly polarized light having an oscillation plane along the first direction X is referred to as first polarized light POL1, and linearly polarized light having an oscillation plane along the second direction Y is referred to as second polarized light POL2. The first polarized light POL1is shown by an arrow of horizontal stripes in the drawing, and the second polarized light POL2is shown by an arrow of slanting stripes in the drawing. Light L is, for example, natural light having random oscillation planes, and is assumed to enter from an outer surface511A of the insulating substrate511, and travel from the first substrate51toward the second substrate52.

The lens5has different functions on the first polarized light POL1and the second polarized light POL2, respectively. That is, of the natural light L, the lens5transmits the second polarized light POL2without practically refracting the second polarized light POL2, and refracts the first polarized light POL1. In other words, the lens5exhibits a focusing function on mainly the first polarized light POLL

FIG. 8is an illustration for explaining a formation example of the lens5provided in the liquid crystal element50.

The first substrate51comprises first control electrodes E11to E19arranged at substantially regular intervals in the first direction X. The second control electrode E2is opposed to the first control electrodes E11to E19with the first liquid crystal layer53interposed therebetween.

As shown inFIG. 8(a), in a state in which a voltage which is different from that applied to the second control electrode E2is applied mainly to the first control electrodes E11, E14, and E17, a lens5A extending over the first control electrodes E11to E14is formed, and also, a lens5B extending over the first control electrodes E14to E17is formed.

As shown inFIG. 8(b), in a state in which a voltage which is different from that applied to the second control electrode E2is applied mainly to the first control electrodes E12, E15, and E18, a lens5C extending over the first control electrodes E12to E15is formed, and also, a lens5D extending over the first control electrodes E15to E18is formed.

As shown inFIG. 8(c), in a state in which a voltage which is different from that applied to the second control electrode E2is applied mainly to the first control electrodes E13, E16, and E19, a lens5E extending over the first control electrodes E13to E16is formed, and also, a lens5F extending over the first control electrodes E16to E19is formed.

In the example illustrated, when the lens5A corresponds to the lens5in the first position P1shown inFIG. 2(a), for example, a voltage applied to the first control electrodes E11and E14, and the second control electrode E2corresponds to a first voltage for forming the lens5at the first position P1in the first mode. Also, when the lens5C corresponds to the lens5in the second position P2shown inFIG. 2(b), a voltage applied to the first control electrodes E12and E15and the second control electrode E2corresponds to a second voltage for forming the lens5at the second position P2in the second mode.

FIG. 9is an illustration showing a configuration example of the light-shielding body4and the lens5. Note that illustration of the liquid crystal element comprising the lens5and the second control electrode is omitted.

In one example, the first control electrodes E1are arranged in the first direction X, each of the first control electrodes E1extends in the second direction Y, and the lens5is a convex lens (a cylindrical lens) extending in the second direction Y and projecting in the third direction Z. The light-shielding body4extends in the second direction Y. Although the light-shielding body4is arranged at a position overlapping the first control electrode E1, a width of the light-shielding body4along the first direction X is not necessarily the same as a width of the first control electrode E1along the first direction X. That is, a single light-shielding body4may overlap a plurality of first control electrodes E1. In a configuration example in which the light-shielding body4and the lens5extend in the second direction Y as described above, the emitting direction can be controlled such that it approximates a direction orthogonal to an extending direction of the light-shielding body4and the lens5in the X-Y plane, in other words, the first direction X, as has been described with reference toFIG. 2, etc. In a configuration example in which the light-shielding body4and the lens5extend in the first direction X, though this is not illustrated in the drawing, by changing a relative positional relationship between the light-shielding body4and the lens5along the second direction Y, the emitting direction can be controlled such that it approximates the second direction Y.

FIG. 10is an illustration showing an example of arrangement of the light-shielding bodies4. Here, an arrangement example in which the light-shielding bodies4are provided in the liquid crystal element50is described.

FIG. 10(a)corresponds to an arrangement example in which the light-shielding bodies4are provided on a first outer surface51A of the first substrate51.FIG. 10(b)corresponds to an arrangement example in which the light-shielding bodies4are provided on a first inner surface51B of the first substrate51.FIG. 10(c)corresponds to an arrangement example in which the light-shielding bodies4are provided on a second inner surface52A of the second substrate52.FIG. 10(d)corresponds to an arrangement example in which the light-shielding bodies4are provided on a second outer surface52B of the second substrate52.

In all of the arrangement examples, the light-shielding bodies4are fixed to predetermined positions, and the positions where they are arranged do not change in either of the modes. Each of these light-shielding bodies4is formed of a resin material colored black, for example, or opaque metal material. Alternatively, the light-shielding body4may be formed of a material which absorbs incident light, or a material which reflects the incident light. When the light-shielding body4is formed of a reflective material, the incident light can be recycled, and the efficiency of use of light can be improved. Further, a direction in which the light-shielding body4extends is parallel to a direction in which the first control electrode E1extends, as has been explained with reference toFIG. 9. Accordingly, when the light-shielding body4is formed of a metal material or a conductive material, the light-shielding body4can also be used as the first control electrode E1.

Next, variations of the liquid crystal element50will be explained.

FIG. 11is an illustration showing a first variation of the liquid crystal element50.

As shown inFIG. 11(a), in a state in which a voltage which is different from that applied to the second control electrode E2is applied mainly to the first control electrodes E11, E13, E15, E17, and E19, each of a lens5A extending over the first control electrodes E11to E13, a lens5B extending over the first control electrodes E13to E15, a lens5C extending over the first control electrodes E15to E17, and a lens5D extending over the first control electrodes E11to E19is formed. The lenses5A to5D each correspond to a first lens having a first width W51along the first direction X. The first width W51corresponds to a pitch between the first control electrodes E11and E13along the first direction X, for example.

As shown inFIG. 11(b), in a state in which a voltage which is different from that applied to the second control electrode E2is applied mainly to the first control electrodes E11, E15, and E19, each of a lens5E extending over the first control electrodes E11to E15, and a lens5F extending over the first control electrodes E15to E19is formed. The lenses5E to5F each correspond to a second lens having a second width W52along the first direction X. The second width W52is different from the first width W51, and in the example illustrated, the second width W52is greater than the first width W51. The second width W52corresponds to a pitch between the first control electrodes E11and E15along the first direction X, for example.

As stated above, the voltages applied to the first control electrode and the second control electrode are controlled by the illumination controller. In the example illustrated inFIG. 11(a), the voltage applied to the first control electrodes E11and E13and the second control electrode E2corresponds to the first voltage for forming the first lens5A. Further, in the example illustrated inFIG. 11(b), the voltage applied to the first control electrodes E11and E15and the second control electrode E2corresponds to the second voltage for forming the second lens5E.

Also in this configuration example, the same advantage as that of the above-described configuration example can be obtained. In addition, by selectively switching the first lens and the second lens having different widths, a range of the emitting direction and a focusing position of the emitted light can be controlled.

FIG. 12is an illustration showing a second variation of the liquid crystal element50.

As shown inFIG. 12(a), in a state in which a voltage which is different from that applied to the second control electrode E2is applied to the first control electrodes E11to E17, a lens5L extending over the first control electrodes E11to E17is formed. The lens5L is a lens which is unsymmetrical with respect to the normal N of the light source unit3or the normal N of the first substrate51. In a first region531on the left side of the drawing, that is, the region extending over the first control electrodes E11to E13, and a second region532on the right side of the drawing, that is, the region extending over the first control electrodes E14to E16, the lens5L has different refractive-index distributions. Such a lens5L can be formed by setting the voltages of the first control electrodes E11to E17to, for example, 6V, 5V, 4V, 3V, 2V, 1V, and 6V, respectively, and setting the voltage of the second control electrode E2to 0V. The lens5L refracts the emitted light from the light source unit3. An emitting direction of the emitted light falls within a range that is unsymmetrical with respect to the normal N. When a range of the emitting direction is assumed as a range of +θ2and −θ3with respect to the normal N, θ2is smaller than θ3.

As shown inFIG. 12(b), in a state in which a voltage which is different from that applied to the second control electrode E2is applied to the first control electrodes E11to E17, a lens5R extending over the first control electrodes E11to E17is formed. The lens5R is a lens which is unsymmetrical with respect to the normal N. Such a lens5R can be formed by setting the voltages of the first control electrodes E11to E17to, for example, 6V, 1V, 2V, 3V, 4V, 5V and 6V, respectively, and setting the voltage of the second control electrode E2to 0V. The lens5R refracts the emitted light from the light source unit3. An emitting direction of the emitted light falls within a range that is unsymmetrical with respect to the normal N. When a range of the emitting direction is assumed as a range of +θ2and −θ3with respect to the normal N,62is greater than θ3.

FIG. 13is an illustration for explaining a formation example of the lenses5L and5R shown inFIG. 12.

As shown inFIG. 13(a), in a state in which voltages of the first control electrodes E11to E17arranged in the first direction X are set such that they are gradually reduced relative to a voltage of the second control electrode E2, the unsymmetrical lens5L extending over the first control electrodes E11to E17is formed.

As shown inFIG. 13(b), in a state in which the voltages of mainly the first control electrodes E11and E17are set to be the same, and the voltages of the first control electrodes E12to E16are each set to 0V or smaller than the voltage of the first control electrode E11, a symmetrical lens5M extending over the first control electrodes E11to E17is formed.

As shown inFIG. 13(c), in a state in which the voltages of the first control electrodes E11to E17are set such that they are gradually increased relative to the voltage of the second control electrode E2, the unsymmetrical lens5R extending over the first control electrodes E11to E17is formed.

In the example illustrated, the lens5M shown inFIG. 13(b)corresponds to the first lens having a symmetrical shape, and the voltage applied to the first control electrodes E11to E17and the second control electrode E2corresponds to the first voltage for forming the first lens5M. Each of the lens5L shown inFIG. 13(a), and the lens5R shown inFIG. 13(c)corresponds to the second lens having an unsymmetrical shape, and the voltage applied to the first control electrodes E11to E17and the second control electrode E2corresponds to the second voltage for forming the second lenses5L and5R.

Also in this configuration example, likewise the above configuration example, by the unsymmetrically-shaped lenses5L and5R, the emitting direction can be controlled such that it approximates the first direction X in the X-Y plane. In addition, in the second variation in which the liquid crystal element50can form the unsymmetrically-shaped lens, the emitting direction can be controlled without using the light-shielding body.

FIG. 14is an illustration showing a third variation of the liquid crystal element50.

The configuration example shown inFIG. 14is different from the above configuration example in that a plurality of second control electrodes E21to E23are arranged at intervals in the first direction X, and each of the second control electrodes E21to E23is a strip electrode extending in the second direction Y. In other words, the extending direction of the second control electrodes E21to E23is parallel to the extending direction of the first control electrodes E11to E13.

In this configuration example, by applying a predetermined voltage mainly to each of the first control electrodes E11to E13, the lenses5A and5B are formed, and by applying a predetermined voltage mainly to each of the second control electrodes E21to E23, the lenses5C and5D are formed. Each of the lenses5A and5B is a convex lens extending in the second direction Y, and projecting upward along the third direction Z. Also, each of the lenses5C and5D is a convex lens extending in the second direction Y, and projecting downward along the third direction Z.

For example, by setting the voltage of each of the second control electrodes E21to E23to 0V, the voltage of each of the first control electrodes E11and E13to 6V, and the voltage of the first control electrode E12to −6V, the lenses5A and5B can be formed without forming the lenses5C and5D. Similarly, by setting the voltage of each of the first control electrodes E11to E13to 0V, the voltage of each of the second control electrode E21and E23to 6V, and the voltage of the second control electrode E22to −6V, the lenses5C and5D can be formed without forming the lenses5A and5B. In addition, by setting the voltage of each of the first control electrodes E11and E13to −6V, and the voltage of the first control electrode E12to +6V, and also setting the voltage of each of the second control electrodes E21and E23to −6V, and the voltage of the second control electrode E22to +6V, the lenses5A and5B and the lenses5C and5D can be formed simultaneously.

Also in this configuration example, the same advantage as that of the above-described configuration example can be obtained.

FIG. 15is an illustration showing a fourth variation of the liquid crystal element50.

The configuration example shown inFIG. 15is different from the above configuration example in that the second control electrodes E21to E23are arranged at intervals in the second direction Y, and each of the second control electrodes E21to E23is a strip electrode extending in the first direction X. In other words, the extending direction of the second control electrodes E21to E23crosses the extending direction of the first control electrodes E11to E13.

In this configuration example, by applying a predetermined voltage mainly to each of the first control electrodes E11to E13, the lenses5A and5B are formed, and by applying a predetermined voltage mainly to each of the second control electrodes E21to E23, the lenses5E and5F are formed. Each of the lenses5A and5B is a convex lens extending in the second direction Y, and projecting upward along the third direction Z. Also, each of the lenses5E and5F is a convex lens extending in the first direction X, and projecting downward along the third direction Z.

For example, by setting the voltage of each of the second control electrodes E21to E23to 0V, the voltage of each of the first control electrodes E11and E13to 6V, and the voltage of the first control electrode E12to −6V, the lenses5A and5B can be formed without forming the lenses5E and5F. Similarly, by setting the voltage of each of the first control electrodes E11to E13to 0V, the voltage of each of the second control electrode E21and E23to 6V, and the voltage of the second control electrode E22to −6V, the lenses5E and5F can be formed without forming the lenses5A and5B.

Also in this configuration example, as the lenses5A and5B are formed without forming the lenses5E and5F, the emitting direction can be controlled such that it approximates the first direction X in the X-Y plane, as in the above configuration example. In addition, by forming the lenses5E and5F without forming the lenses5A and5B, the emitting direction can be controlled such that it approximates the second direction Y in the X-Y plane.

Next, the liquid crystal element40comprising the light-shielding body4will be described. The liquid crystal element40corresponds to a second liquid crystal element.

FIG. 16is a cross-sectional view showing a configuration example of the liquid crystal element40.

The liquid crystal element40comprises a third substrate41, a fourth substrate42, a second liquid crystal layer43, a third control electrode E3, a fourth control electrode E4, a first polarizer46, and a second polarizer47. In the example illustrated, the third control electrode E3is provided on the third substrate41, and the fourth control electrode E4is provided on the fourth substrate42. However, the third control electrode E3and the fourth control electrode E4may both be provided on the same substrate, that is, on the third substrate41or the fourth substrate42.

The third substrate41comprises an insulating substrate411, a plurality of third control electrodes E3, an alignment film412, and a feeder413. The third control electrode E3is located between the insulating substrate411and the second liquid crystal layer43. The third control electrodes E3are arranged at intervals in the first direction X in an effective area40A. In one example, a width of each of the third control electrodes E3along the first direction X is greater than an interval between adjacent third control electrodes E3along the first direction X. The alignment film412covers the third control electrodes E3, and is in contact with the second liquid crystal layer43. The feeder413is located in a non-effective area40B outside the effective area40A.

The fourth substrate42comprises an insulating substrate421, the fourth control electrode E4, and an alignment film422. The fourth control electrode E4is located between the insulating substrate421and the second liquid crystal layer43. The fourth control electrode E4is, for example, a single plate electrode which is located on substantially the entire surface of the effective area40A, and also extends to the non-effective area40B. The fourth control electrode E4is opposed to the third control electrode E3via the second liquid crystal layer43in the effective area40A. The fourth control electrode E4is opposed to the feeder413in the non-effective area40B. The alignment film422covers the fourth control electrode E4, and is in contact with the second liquid crystal layer43.

The first polarizer46is arranged on a third outer surface41A of the third substrate41. The second polarizer47is arranged on a fourth outer surface42B of the fourth substrate42.

Each of the insulating substrates411and421is, for example, a glass substrate or a resin substrate. Each of the third control electrode E3and the fourth control electrode E4is formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The third control electrode E3is a strip electrode extending in the second direction Y, similarly to the first control electrode E1shown inFIG. 5. The fourth control electrode E4is a rectangular plate electrode, similarly to the second control electrode E2shown inFIG. 5. Each of the alignment films412and422is, for example, a horizontal alignment film. In one example, the alignment film412is subjected to alignment treatment in the first direction X, and the alignment film422is subjected to alignment treatment in the second direction Y.

The third substrate41and the fourth substrate42are bonded to each other by a sealant44in the non-effective area40B. The sealant44includes a conductive material45. The conductive material45is interposed between the feeder413and the fourth control electrode E4, and electrically connects the feeder413and the fourth control electrode E4.

The second liquid crystal layer43is held between the third substrate41and the fourth substrate42. The second liquid crystal layer43is formed of, for example, a liquid crystal material having positive dielectric anisotropy. The third control electrode E3and the fourth control electrode E4apply, to the second liquid crystal layer43, a voltage for forming the light-shielding body4in the second liquid crystal layer43.

The illumination controller8controls the voltage to be applied to the second liquid crystal layer43. By controlling the voltage to be applied to each of the third control electrode E3and the fourth control electrode E4, the illumination controller8can switch a mode between a mode in which the light-shielding body is formed in the second liquid crystal layer43and a mode in which a light-shielding body is not formed in the second liquid crystal layer43. Further, by controlling the voltage to be applied to each of the third control electrodes E3, the illumination controller8can control a position where the light-shielding body is formed. More specifically, the illumination controller8can form the light-shielding body4at each of the first position P1and the second position P2, as in the case of the lens5explained with reference toFIGS. 2 and 3. Furthermore, by controlling the voltage to be applied to each of the third control electrodes E3, the illumination controller8can control the size of the light-shielding body4freely.

FIG. 17is an illustration for explaining the light-shielding body4formed in the liquid crystal element40.FIG. 17illustrates only the structures necessary for explanation. Here, a case where a voltage, which is different from that applied to the fourth control electrode E4, is applied to third control electrodes E31, E33, and E35, of a plurality of third control electrodes E31to E35arranged in the first direction X, will be described.

In one example, the voltage of the third control electrodes531, E33, and E35is 6V, and the voltage of the third control electrode E32and the fourth control electrode E4is 0V. In addition, as described above, the second liquid crystal layer43has positive dielectric anisotropy. Liquid crystal molecules43M included in the second liquid crystal layer43are twist-aligned at an angle of 90° in a state where no electric field is formed. In other words, the liquid crystal molecules43M near the alignment film412are initially aligned such that their major axes are aligned in the first direction X, and the liquid crystal molecules43M near the alignment film422are initially aligned such that their major axes are aligned in the second direction Y. Further, the liquid crystal molecules43M are aligned such that their major axes are aligned along an electric field in a state where the electric field is formed.

In a region in which each of the third control electrodes E31, E33, and E35is opposed to the fourth control electrode E4, an electric field along the third direction Z is formed. Therefore, the liquid crystal molecules43M are vertically aligned such that their major axes are aligned along the third direction Z. In a region in which each of the third control electrodes E32and E34is opposed to the fourth control electrode E4, an electric field is not formed. Therefore, the liquid crystal molecules43M are maintained in the initial alignment state, and twist-aligned.

In the example illustrated, a transmission axis46T of the first polarizer46is set to the first direction X, and a transmission axis47T of the second polarizer47is set to the second direction Y. Accordingly, light incident on the third substrate41through the first polarizer46is linearly polarized light L1having an oscillation plane along the first direction X. A polarization axis of the linearly polarized light L1, which is incident on a region in which the third control electrode E32and the fourth control electrode E4are opposed to each other, is rotated due to influence of the liquid crystal molecules43M twist-aligned, and the linearly polarized light L1is changed to linearly polarized light L2having an oscillation plane along the second direction Y after passing through the second liquid crystal layer43. The linearly polarized light L2passes through the second polarizer47. Also in a region in which the third control electrode E34and the fourth control electrode E4are opposed to each other, the linearly polarized light L2is similarly transmitted. Meanwhile, the linearly polarized light L1incident on a region in which the third control electrode E33and the fourth control electrode E4are opposed to each other is hardly influenced by the liquid crystal molecules43M that are vertically aligned, and passes through the second liquid crystal layer43while the polarization axis is kept unchanged. Such linearly polarized light L1is absorbed by the second polarizer47. In regions in which the third control electrodes E31and E35are opposed to the fourth control electrode E4, the linearly polarized light L1is similarly absorbed.

In other words, regions in which the third control electrodes E31, E33, and E35are opposed to the fourth control electrode E4correspond to the light-shielding bodies4A which block light as shown inFIG. 2, and regions in which the third control electrodes E32and E34are opposed to the fourth control electrode E4correspond to gaps G4through which light is transmitted as shown inFIG. 2. In a case where each of the third control electrodes E3is a strip electrode extending in the second direction Y, the light-shielding bodies4are also formed in a strip shape extending in the second direction Y.

In the present embodiment, a system in which the second liquid crystal layer43including liquid crystal molecules twist-aligned in the initial alignment state, and an electric field formed along a direction intersecting the substrate main surface are combined has been explained, as an example of the liquid crystal element40comprising the light-shielding body4. However, the liquid crystal element40comprising the light-shielding body4is not limited to the above. That is, as long as the system can selectively make a change between a state in which the light is blocked and a state in which light is transmitted in accordance with a voltage to be applied to the second liquid crystal layer43, a liquid crystal element comprising the light-shielding body4can be realized.

FIG. 18is an illustration for explaining a formation example of the light-shielding body4provided in the liquid crystal element40.

The third substrate41comprises the third control electrodes E31to E37arranged at substantially regular intervals in the first direction X. The fourth control electrode E4is opposed to the third control electrodes E31to E37with the second liquid crystal layer43interposed therebetween.

As shown inFIG. 18(a), in a state in which a voltage which is different from that applied to the fourth control electrode E4is applied mainly to the third control electrodes E31, E32, E35, and E36, the light-shielding body4A extending over the third control electrodes E31and E32is formed, and also, the light-shielding body4B extending over the third control electrodes E35and E36is formed. Also, a gap G41extending over the third control electrodes E33and E34is formed.

As shown inFIG. 18(b), in a state in which a voltage which is different from that applied to the fourth control electrode E4is applied mainly to the third control electrodes E32, E33, E36, and E37, a light-shielding body4C extending over the third control electrodes E32and E33is formed, and also, a light-shielding body4D extending over the third control electrodes E36and E37is formed. Also, a gap G42extending over the third control electrodes E34and E35is formed.

In the example illustrated, when the light-shielding bodies4A and4B correspond to the light-shielding bodies in the first position P1shown inFIG. 2(a), for example, a voltage applied to the third control electrodes E31, E32, E35, and E36, and the fourth control electrode E4corresponds to a third voltage for forming the light-shielding bodies at the first position P1in the first mode. Also, when the light-shielding bodies4C and4D correspond to the light-shielding bodies in the second position P2shown inFIG. 2(b), a voltage applied to the third control electrodes E32, E33, E36, and E37, and the fourth control electrode E4corresponds to a fourth voltage for forming the light-shielding bodies at the second position P2in the second mode.

FIG. 19is an illustration showing an example of arrangement of the lenses5. Here, an arrangement example in which the lenses5are provided in the liquid crystal element40is described.

FIG. 19(a)corresponds to an arrangement example in which the lenses5are provided on the second polarizer47.FIG. 19(b)corresponds to an arrangement example in which the lenses5are provided on the first polarizer46. Alternatively, a lens sheet on which the lenses5are formed may be attached to any of the third substrate41, the fourth substrate42, the first polarizer46, and the second polarizer47.

In all of the arrangement examples, the lenses5are fixed to predetermined positions, and the positions where they are arranged do not change in either of the modes. Such lenses5are formed of, for example, a transparent resin material or glass.

Next, variations of the liquid crystal element40will be explained.

FIG. 20is an illustration showing a variation of the liquid crystal element40.

As shown inFIG. 20(a), in a state in which a voltage which is different from that applied to the fourth control electrode E4is applied mainly to the third control electrodes E31, E32, E35, and E36, each of the light-shielding body4A extending over the third control electrodes E31and E32and the light-shielding body4B extending over the third control electrodes E35and E36is formed. The light-shielding bodies4A and4B each correspond to a first light-shielding body having a third width W43along the first direction X. The third width W43corresponds substantially to a width of the third control electrodes E31and E32along the first direction X, for example. Also, the gap G41corresponds substantially to a width of the third control electrodes E33and E34along the first direction X. In the example illustrated, although the third width W43and the gap G41are equal to each other in size, their sizes may be different. The third width W43and the gap G41can be controlled in accordance with the number of third control electrodes to which voltages are applied.

As shown inFIG. 20(b), in a state in which a voltage which is different from that applied to the fourth control electrode E4is applied mainly to the third control electrodes E31to E33, and E35to E37, each of the light-shielding body4C extending over the third control electrodes E31to E33and the light-shielding body4D extending over the third control electrodes E35to E37is formed. The light-shielding bodies4C and4D each correspond to a second light-shielding body having a fourth width W44along the first direction X. The third width W43is different from the fourth width W44, and in the example illustrated, the fourth width W44is greater than the third width W43. The fourth width W44corresponds substantially to a width of the third control electrodes E31to E33along the first direction X, for example. Also, the gap G42corresponds substantially to a width of the third control electrode E34along the first direction X. In the example illustrated, although the fourth width W44is greater than the gap G42, they may be equal to each other. The fourth width W44and the gap G42can be controlled in accordance with the number of third control electrodes to which voltages are applied.

As stated above, the voltages applied to the third control electrode and the fourth control electrode are controlled by the illumination controller. In the example illustrated inFIG. 20(a), the voltage applied to the third control electrodes E31and E32and the fourth control electrode E4corresponds to the third voltage for forming the first light-shielding body4A having the third width W43. Also, in the example illustrated inFIG. 20(b), the voltage applied to the third control electrodes E31to E33and the fourth control electrode E4corresponds to the fourth voltage for forming the second light-shielding body4C having the fourth width W44.

Also in this configuration example, the same advantage as that of the above-described configuration example can be obtained. In addition, by selectively switching the first light-shielding body and the second light-shielding body having different widths, a range of the emitting direction and a focusing position of the emitted light can be controlled.

Next, an example of the display device DSP will be explained.

FIG. 21is an illustration showing a first example of the display device DSP. More specifically, the display device DSP comprises the display panel1, the light source unit3, the light-shielding body4, and the liquid crystal element50which can form the lens5. In the example illustrated, while the light-shielding body4is provided on the first outer surface51A of the first substrate51, it may be provided at any place between the display panel1and the light source unit3. The display panel1comprises an array substrate11, a counter-substrate12, a liquid crystal layer13, a sealant14, polarizers15and16, etc. The light-shielding body4and the liquid crystal element50are located between the light source unit3and the polarizer15. When the lens5provided in the liquid crystal element50has the function of refracting the first polarized light POL1as explained with reference toFIG. 7, a transmission axis of the polarizer15is set parallel to the first direction X so as to allow the first polarized light POL1to be transmitted.

FIG. 22is an illustration showing a basic structure and an equivalent circuit of the display panel1shown inFIG. 21.

The display panel1includes a display area DA in which an image is displayed, and a non-display area NDA which surrounds the display area DA. The display area DA comprises a plurality of pixels PX. Here, the pixel indicates a minimum unit which can be individually controlled in accordance with a pixel signal, and exists in, for example, an area including a switching element arranged at a position where a scanning line and a signal line, which will be described later, cross each other. The pixels PX are arrayed in a matrix in the first direction X and the second direction Y. Also, the display panel1includes scanning lines (also referred to as gate lines) G (G1to Gn), signal lines (also referred to as data lines or source lines) S (S1to Sm), a common electrode CE, etc., in the display area DA. The scanning lines G extend in the first direction X, and are arranged in the second direction Y. The signal lines S extend in the second direction Y, and are arranged in the first direction X. Note that the scanning lines G and the signal lines S do not necessarily extend linearly, and may be partially bent. The common electrode CE is disposed over the pixels PX. The scanning lines G are connected to a scanning line drive circuit GD, the signal lines S are connected to a signal line drive circuit SD, and the common electrode CE is connected to a common electrode drive circuit CD. The scanning line drive circuit GD, the signal line drive circuit SD, and the common electrode drive circuit CD are controlled by the display controller7.

Each of the pixels PX comprises a switching element SW, a pixel electrode PE, the common electrode CE, the liquid crystal layer13, and the like. The switching element SW is constituted by a thin-film transistor (TFT), for example, and is electrically connected to the scanning line G and the signal line S. More specifically, the switching element SW includes a gate electrode WG, a source electrode WS, and a drain electrode WD. The gate electrode WG is electrically connected to the scanning ling G. In the example illustrated, the electrode electrically connected to the signal line S is referred to as the source electrode WS, and the electrode electrically connected to the pixel electrode PE is referred to as the drain electrode WD. The scanning line G is connected to the switching elements SW of the respective pixels PX arranged in the first direction X. The signal line S is connected to the switching elements SW of the respective pixels PX arranged in the second direction Y.

The pixel electrode PE is electrically connected to the switching element SW. The common electrode CE is opposed to a plurality of pixel electrodes PE. The pixel electrode PE and the common electrode CE function as drive electrodes which drive the liquid crystal layer13. The pixel electrode PE is formed of a transparent conductive material such as ITO or IZO, or a reflective metal material such as aluminum or silver. Further, the common electrode CE is formed of a transparent conductive material such as ITO or IZO. A storage capacitance CS is formed between, for example, the common electrode CE and the pixel electrode PE.

Although the details of the structure of the display panel1will not be described here, the display panel1has a structure corresponding to one of various modes including a twisted nematic (TN) mode, a polymer dispersed liquid crystal (PDLC) mode, an optically compensated bend (OCB) mode, an electrically controlled birefringence (ECB) mode, a vertically aligned (VA) mode, a fringe field switching (FFS) mode, and in-plane switching (IPS) mode. Also, while explanation has been provided for a case where each of the pixels PX is driven by an active method, the pixels PX may be driven by a passive method.

FIG. 23is a cross-sectional view showing a configuration example of the display panel1shown inFIG. 22. Here, a cross-sectional structure of the display panel1adopting a fringe field switching (FFS) mode, which is one of display modes using a lateral electric field, will be explained briefly. In the example illustrated, the display panel1includes a red pixel PXR which displays red, a green pixel PXG which displays green, and a blue pixel PXB which displays blue, in the display area DA. However, the display panel1may include a pixel which displays the other color. For example, from the standpoint of improving the transmissivity of the display panel1, the display panel1should preferably include a pixel which displays white or a transparent pixel.

The array substrate11includes a first insulating substrate100, a first insulating film110, the common electrode CE, a second insulating film120, pixel electrodes PE1to PE3, a first alignment film AL1, and the like. The common electrode CE extends over the red pixel PXR, the green pixel PXG, and the blue pixel PXB. Each of the pixel electrode PE1of the red pixel PXR, the pixel electrode PE2of the green pixel PXG, and the pixel electrode PE3of the blue pixel PXB is opposed to the common electrode CE, and includes slits SLA. In the example illustrated, the common electrode CE is located between the first insulating film110and the second insulating film120, and the pixel electrodes PE1to PE3are located between the second insulating film120and the first alignment film AL1. Alternatively, the pixel electrodes PE1to PE3may be located between the first insulating film110and the second insulating film120, and the common electrode CE may be located between the second insulating film120and the first alignment film AL1. In this case, the slits SLA are formed in the common electrode CE.

The counter-substrate12includes a second insulating substrate200, a light-shielding layer BM, color filters CFR, CFG, and CFB, an overcoat layer OC, a second alignment film AL2, and the like. The color filters CFR, CFG, and CFB are opposed to the pixel electrodes PE1to PE3, respectively, with the liquid crystal layer13interposed therebetween. The color filter CFR is a red color filter, the color filter CFG is a green color filter, and the color filter CFB is a blue color filter.

Note that, although color filters CFR, CFG, and CFB are formed in the counter-substrate12in the example illustrated, they may be formed in the array substrate11instead. Although the light-shielding layer BM is located between adjacent color filters, it may be omitted in terms of improving the transmissivity of the display panel1. If color display is unnecessary, color filters are omitted.

The liquid crystal layer13is sealed between the first alignment film AL1and the second alignment film AL2. Each of the first alignment film AL1and the second alignment film AL2is a horizontal alignment film.

In an off-state in which no electric field is produced between the pixel electrode PE and the common electrode CE, the liquid crystal molecules LM included in the liquid crystal layer13are initially aligned in a direction substantially parallel to the X-Y plane by an alignment restriction force of the first alignment film AL1and the second alignment film AL2. In an on-state in which an electric field is produced between the pixel electrode PE and the common electrode CE, the liquid crystal molecules LM are aligned in a direction different from the initial alignment direction, in the X-Y plane.

According to the display device DSP of the first example described above, while a position of the light-shielding body4does not change, a position of the lens5can be changed freely. By selectively changing a relative positional relationship between the light-shielding body4and the lens5, the emitting direction of light emitted from the display device DSP can be controlled. In other words, a viewing angle can be freely controlled for an observer who observes the display device DSP. For example, switching can be conducted between a narrow-viewing-angle mode of a first angular range and a wide-viewing-angle mode of a second angular range which is greater than the first angular range. Also, it is possible to switch between a first viewing angle mode including an observation angle that enables observation mainly in a normal direction of the display device DSP and a second viewing angle mode including an observation angle that enables observation in a direction inclined with respect to the normal of the display device DSP.

FIG. 24is an illustration for explaining an example of the positional relationship between a pixel opening OP of the display panel1and the lens5. Here, the pixel opening OP corresponds to a region which can transmit light in each of the red pixel PXR, the green pixel PXG, and the blue pixel PXB explained with reference toFIG. 23, or a region surrounded by the light-shielding layers BM.

In one example, pitch P5between the lenses5is less than or equal to pitch POP between the pixel openings OP. Thereby, light beams refracted by the lenses5are guided to the pixel openings OP, respectively. Light beams transmitted through the corresponding pixel openings OP are oriented in a certain direction, and observed at the same observation position. For example, as compared to a case where a light beam transmitted through a first pixel opening is observed at a first observation position, and a light beam transmitted through a second pixel opening is observed at a second observation position that is different from the first observation position, when both of the light beams transmitted through the first pixel opening and the second pixel opening are observed at the first observation position, deterioration in the resolution can be suppressed.

Also, since a focusing position5P of the lens5as illustrated in the drawing is located in the pixel opening OP, efficiency of use of light can be improved, and thus, the brightness can be improved.

FIG. 25is an illustration showing a second example of the display device DSP. More specifically, the display device DSP comprises the display panel1, the light source unit3, the liquid crystal element40which can form the light-shielding body4, and the lens5. In the example illustrated, while the lens5is provided between the display panel1and the liquid crystal element40, it may be provided at any place between the display panel1and the light source unit3. The structures of the display panel1and the liquid crystal element40are described above, and explanation of these structures is omitted.

According to the display device DSP of the second example described above, while a position of the lens5does not change, a position of the light-shielding body4can be changed freely. By selectively changing a relative positional relationship between the light-shielding body4and the lens5, the same advantage as that of the first example can be obtained.

FIG. 26is an illustration showing a third example of the display device DSP. More specifically, the display device DSP comprises the display panel1, the light source unit3, the liquid crystal element40which can form the light-shielding body4, and the liquid crystal element50which can form the lens5. In the example illustrated, while the liquid crystal element50is provided between the display panel1and the liquid crystal element40, it may be provided between the light source unit3and the liquid crystal element40. The structures of the display panel1, the liquid crystal element40, and the liquid crystal element50are described above, and explanation of these structures is omitted.

According to the display device DSP of the third example described above, while a position of the lens5does not change, a position of the light-shielding body4can be changed freely. By selectively changing a relative positional relationship between the light-shielding body4and the lens5, the same advantage as that of the first example can be obtained. In addition, by changing the arrangement position of the light-shielding body4and the lens5according to the position of the observer, the emitting direction of light can be reoriented in accordance with the observation position of a moving observer (i.e., to follow the observer). Also, the light-shielding body4can be used as a parallax barrier, and by a combination of the light-shielding body4and the lens5, switching can be conducted between a two-dimensional image display mode and a three-dimensional image display mode.

FIG. 27is an illustration showing a fourth example of the display device DSP. More specifically, the display device DSP comprises the display panel1, the light source unit3, the liquid crystal element40awhich can form the light-shielding body4a, and the liquid crystal element40bwhich can form the light-shielding body4b. The structures of the liquid crystal elements40aand40bare the same as the structure of the liquid crystal element40. The light-shielding body4acorresponds to a first light control body which controls an output angle of light emitted from the light source unit3. The light-shielding body4bcorresponds to a second light control body which controls an output angle of light emitted from the liquid crystal element40a.

In the fourth example, a liquid crystal element which can form the lens is not provided. However, as the light-shielding bodies4aand4bwhich control the output angle are arranged along the third direction Z, the emitting direction can be controlled, and the same advantage as that of the first example can be obtained. As described above, according to the present embodiment, it is possible to provide a display device and an illumination device capable of controlling a direction of emission of light.

The present invention is not limited to the embodiments described above but the constituent elements of the invention can be modified in various manners without departing from the spirit and scope of the invention. Various aspects of the invention can also be extracted from any appropriate combination of a plurality of constituent elements disclosed in the embodiments. Some constituent elements may be deleted in all of the constituent elements disclosed in the embodiments. The constituent elements described in different embodiments may be combined arbitrarily.