Liquid crystal light control device

Abstract

A liquid crystal light control device includes a first liquid crystal cell, a second liquid crystal cell overlapping the first liquid crystal cell, a third liquid crystal cell overlapping the second liquid crystal cell, and a fourth liquid crystal cell overlapping the third liquid crystal cell. The first liquid crystal cell, the second liquid crystal cell, the third liquid crystal cell, and the fourth liquid crystal cell each include a first substrate having a first alignment film, a second substrate having an electrode including a strip-shaped pattern and a second alignment film, and a liquid crystal layer between the first substrate and the second substrate, an alignment direction of the first alignment film and an alignment direction of the second alignment film are set to cross. A long side direction of the strip-shaped pattern of the electrode including the strip-shaped pattern is arranged in a direction crossing the alignment direction of the second alignment film, the electrode including the strip-shaped pattern generates a lateral electric field in the same direction as the alignment direction of the second alignment film.

Description

Technical Field

[0001] One embodiment of the present invention relates to an apparatus for controlling the light distribution of light emitted from a light source by utilizing the electro-optic effect of liquid crystals. Background Technology

[0002] Technology for controlling the light distribution of light emitted from a light source using liquid crystal elements is known. For example, an illumination device is disclosed that controls the amplification of light emitted from a light source by using a liquid crystal cell with concentric circular electrodes (see Patent Documents 1 and 2).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2010-230887

[0006] Patent Document 2: Japanese Patent Application Publication No. 2005-317879 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] Liquid crystal elements using nematic liquid crystals can rotate the orientation of the polarization component of incident light (hereinafter, this phenomenon will also be referred to as optical rotation). Alternatively, incident light can be diffused by creating a refractive index distribution in the liquid crystal layer. In such liquid crystal elements, when incident light undergoes optical rotation after being diffused by the liquid crystal layer, there is a situation where the loss of the rotated light increases, leading to a disorder in the shape of the light distribution pattern.

[0009] One objective of one embodiment of the present invention is to provide a liquid crystal light control device that suppresses light loss and light distribution pattern disorder.

[0010] Technical solutions for solving technical problems

[0011] An embodiment of the present invention relates to a liquid crystal light control device comprising: a first liquid crystal unit, a second liquid crystal unit overlapping the first liquid crystal unit, a third liquid crystal unit overlapping the second liquid crystal unit, and a fourth liquid crystal unit overlapping the third liquid crystal unit. Each of the first, second, third, and fourth liquid crystal units comprises: a first substrate having a first alignment film; a second substrate having an electrode comprising a strip-shaped pattern and a second alignment film; and a liquid crystal layer between the first and second substrates, wherein the alignment direction of the first alignment film and the alignment direction of the second alignment film are intersected. The long side direction of the strip-shaped pattern of the electrode comprising the strip-shaped pattern is arranged in a direction intersecting the alignment direction of the second alignment film, and the electrode comprising the strip-shaped pattern generates a transverse electric field in the same direction as the alignment direction of the second alignment film.

[0012] An embodiment of the present invention relates to a liquid crystal light control device comprising: a first liquid crystal cell, a second liquid crystal cell overlapping the first liquid crystal cell, a third liquid crystal cell overlapping the second liquid crystal cell, and a fourth liquid crystal cell overlapping the third liquid crystal cell. Each of the first, second, third, and fourth liquid crystal cells includes: a first substrate having a first electrode and a first alignment film having a strip-shaped pattern; a second substrate having a second electrode and a second alignment film having a strip-shaped pattern; and a liquid crystal layer between the first and second substrates. The alignment direction of the first alignment film intersects with the alignment direction of the second alignment film. The long side direction of the strip-shaped pattern of the first electrode intersects with the long side direction of the strip-shaped pattern of the second electrode. The long side direction of the strip-shaped pattern of the second electrode is arranged in a direction intersecting with the alignment direction of the second alignment film. In the first and third liquid crystal cells, the second electrode generates a lateral electric field in the same direction as the alignment direction of the second alignment film. In the second and fourth liquid crystal cells, the first electrode generates a lateral electric field in the same direction as the alignment direction of the first alignment film. Attached Figure Description

[0013] Figure 1 This is a perspective view schematically illustrating the configuration of a liquid crystal light control device according to an embodiment of the present invention.

[0014] Figure 2 This diagram shows an unfolded view of a liquid crystal light control element constituting a liquid crystal light control device according to an embodiment of the present invention.

[0015] Figure 3 This is a perspective view showing the electrode configuration of a first liquid crystal cell, a second liquid crystal cell, a third liquid crystal cell, and a fourth liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention.

[0016] Figure 4A This is a top view showing the electrodes disposed on the first substrate of the liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention.

[0017] Figure 4B This is a top view showing the electrodes disposed on the second substrate of the liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention.

[0018] Figure 5 This is a diagram showing an example of the cross-sectional structure of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention.

[0019] Figure 6A This is a diagram illustrating the operation of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention, showing the orientation state of liquid crystal molecules in a state where no voltage is applied.

[0020] Figure 6B This is a diagram illustrating the operation of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention, showing the orientation state of the liquid crystal molecules when a voltage is applied.

[0021] Figure 6C This is a diagram illustrating the operation of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention, showing the waveform of a control signal applied to an electrode driving the liquid crystal.

[0022] Figure 7A This is a diagram illustrating the operation of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention, showing a perspective view of the arrangement of the first electrode and the second electrode.

[0023] Figure 7B This is a diagram illustrating the operation of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention, showing the orientation state of the liquid crystal molecules when a voltage is applied to the first electrode.

[0024] Figure 7C This is a diagram illustrating the operation of a liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention, showing the orientation state of the liquid crystal molecules when a voltage is applied to the second electrode.

[0025] Figure 8 This diagram schematically illustrates the phenomenon of diffusion of the first and second polarization components through two liquid crystal cells.

[0026] Figure 9 This is a perspective view showing the electrode configuration of a first liquid crystal cell, a second liquid crystal cell, a third liquid crystal cell, and a fourth liquid crystal cell constituting a liquid crystal light control element according to an embodiment of the present invention.

[0027] Figure 10 This is a diagram illustrating the operation of a liquid crystal light control device according to an embodiment of the present invention.

[0028] Figure 11 The signal shown controls the operation of a liquid crystal light control device according to an embodiment of the present invention.

[0029] Figure 12 This is a diagram illustrating the operation of a liquid crystal light control device according to an embodiment of the present invention.

[0030] Figure 13 This is a diagram illustrating the operation of a liquid crystal light control device according to an embodiment of the present invention.

[0031] Figure 14 This is a diagram illustrating the configuration of a liquid crystal light control device according to an embodiment of the present invention.

[0032] Figure 15 This is a diagram illustrating the configuration of a liquid crystal light control device according to an embodiment of the present invention.

[0033] Figure 16 This is a diagram illustrating the operation of a liquid crystal light control device according to an embodiment of the present invention.

[0034] Figure 17A An example of an orientation shape obtained by the liquid crystal light control element shown in the first embodiment is shown.

[0035] Figure 17B An example of an orientation shape obtained by the liquid crystal light control element shown in Reference Example 1 is shown.

[0036] Figure 18A An example of an orientation shape obtained by the liquid crystal light control element shown in the second embodiment is shown.

[0037] Figure 18B An example of an orientation shape obtained by the liquid crystal light control element shown in Reference Example 2 is shown. Detailed Implementation

[0038] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention can be implemented in many different ways and is not limited to the description of the embodiments illustrated below. For clarity, the drawings may only schematically show the width, thickness, shape, etc. of each part compared to the actual embodiment; however, this is merely an example and not intended to limit the interpretation of the present invention. Furthermore, in this specification and the drawings, the same reference numerals (or reference numerals such as a, b, etc.) are used for elements that are the same as those previously described in the drawings, and detailed descriptions are sometimes appropriately omitted. Moreover, the words "first" and "second" are used to distinguish the elements and do not have any meaning beyond their scope unless otherwise specified.

[0039] In this specification, the term "above (or below)" a component or region, unless otherwise specified, includes not only the case where it is located directly above (or directly below) another component or region, but also the case where it is located above (or below) another component or region, that is, it also includes the case where other constituent elements are contained between the component or region above (or below) it.

[0040] In this specification, "optical rotation" refers to the phenomenon that linearly polarized components rotate their polarization axis when passing through a liquid crystal layer.

[0041] In this specification, the "orientation direction" of an alignment film refers to the direction in which liquid crystal molecules are oriented when an alignment constraint force is applied to the alignment film (e.g., a rubbing process) to orient the liquid crystal molecules on the alignment film. When the alignment film is subjected to a rubbing process, the orientation direction of the alignment film is usually the rubbing direction.

[0042] In this specification, the "long side direction" of a strip pattern refers to the direction in which the long side of a pattern having a short side (width) and a long side (length) extends when viewed from above. It should be noted that strip patterns include patterns that appear rectangular when viewed from above, as well as patterns that bend or curve at least once along their long side.

[0043] Figure 1 A perspective view of a liquid crystal light control device 100 according to an embodiment of the present invention is shown. The liquid crystal light control device 100 includes a liquid crystal light control element 102 and a circuit board 104. The liquid crystal light control element 102 includes a plurality of liquid crystal cells. In this embodiment, the liquid crystal light control element 102 includes at least four liquid crystal cells.

[0044] Figure 1 An example of a liquid crystal light control element 102 is shown, comprising a first liquid crystal unit 10, a second liquid crystal unit 20, a third liquid crystal unit 30, and a fourth liquid crystal unit 40. The first liquid crystal unit 10, the second liquid crystal unit 20, the third liquid crystal unit 30, and the fourth liquid crystal unit 40 are flat panels arranged with their flat surfaces overlapping. Transparent adhesive layers (not shown) are provided between the first liquid crystal unit 10 and the second liquid crystal unit 20, between the second liquid crystal unit 20 and the third liquid crystal unit 30, and between the third liquid crystal unit 30 and the fourth liquid crystal unit 40. The liquid crystal light control element 102 has a structure in which adjacent liquid crystal units are bonded to each other by the transparent adhesive layers.

[0045] The circuit board 104 includes a circuit for driving the liquid crystal light control element 102. A first liquid crystal cell 10 is connected to the circuit board 104 via a first flexible wiring substrate F1, a second liquid crystal cell 20 is connected to the circuit board 104 via a second flexible wiring substrate F2, a third liquid crystal cell 30 is connected to the circuit board 104 via a third flexible wiring substrate F3, and a fourth liquid crystal cell 40 is connected to the circuit board 104 via a fourth flexible wiring substrate F4. The circuit board 104 outputs control signals to each liquid crystal cell via the flexible wiring substrates to control the orientation state of the liquid crystal.

[0046] Figure 1The liquid crystal light control device 100 shown has a light source unit 106 disposed on the back side of the liquid crystal light control element 102. The liquid crystal light control device 100 is configured such that light emitted from the light source unit 106 passes through the liquid crystal light control element 102 and exits towards the front side of the drawing. The liquid crystal light control element 102 has a first liquid crystal cell 10, a second liquid crystal cell 20, a third liquid crystal cell 30, and a fourth liquid crystal cell 40 arranged sequentially from the light source unit 106 side.

[0047] The light source unit 106 includes a white light source, and optical elements such as lenses may be arranged between the white light source and the liquid crystal light control element 102 as needed. The white light source is a light source that emits light close to natural light, or it may be a light source that emits dimmed light, such as daylight color or bulb color. The liquid crystal light control device 100 has the function of controlling the diffusion direction of the light emitted from the light source unit 106 via the liquid crystal light control element 102. The liquid crystal light control element 102 has the function of shaping the light emitted from the light source unit 106 into a light distribution pattern such as a square or cross.

[0048] Figure 2 Show Figure 1 The diagram shows an unfolded view of the liquid crystal light control element 102. The liquid crystal light control element 102 includes a first liquid crystal unit 10, a second liquid crystal unit 20, a third liquid crystal unit 30, and a fourth liquid crystal unit 40.

[0049] The first liquid crystal unit 10 includes a first substrate S11 and a second substrate S12. The first substrate S11 and the second substrate S12 are arranged opposite each other with a gap between them. A liquid crystal layer (not shown) is provided in the gap between the first substrate S11 and the second substrate S12. A first flexible wiring substrate F1 is connected to the first substrate S11.

[0050] The second liquid crystal unit 20 includes a first substrate S21, a second substrate S22, and a second flexible wiring substrate F2, and has the same configuration as the first liquid crystal unit 10. The third liquid crystal unit 30 includes a first substrate S31, a second substrate S32, and a third flexible wiring substrate F3, and has the same configuration as the first liquid crystal unit 10. The fourth liquid crystal unit 40 includes a first substrate S41, a second substrate S42, and a fourth flexible wiring substrate F4, and has the same configuration as the first liquid crystal unit 10.

[0051] A first transparent adhesive layer TA1 is disposed between the first liquid crystal cell 10 and the second liquid crystal cell 20. The first transparent adhesive layer TA1 allows visible light to pass through and bonds the second substrate S12 of the first liquid crystal cell 10 to the first substrate S21 of the second liquid crystal cell 20. A second transparent adhesive layer TA2 is disposed between the second liquid crystal cell 20 and the third liquid crystal cell 30. The second transparent adhesive layer TA2 allows visible light to pass through and bonds the second substrate S22 of the second liquid crystal cell 20 to the first substrate S31 of the third liquid crystal cell 30. A third transparent adhesive layer TA3 is disposed between the third liquid crystal cell 30 and the fourth liquid crystal cell 40. The third transparent adhesive layer TA3 allows visible light to pass through and bonds the second substrate S32 of the third liquid crystal cell 30 to the first substrate S41 of the fourth liquid crystal cell 40.

[0052] The first transparent adhesive layer TA1, the second transparent adhesive layer TA2, and the third transparent adhesive layer TA3 preferably have high transmittance and refractive indices close to those of the first substrate S11, S21, S31, S41 and the second substrate S12, S22, S23, S24. Optically elastic resins can be used as the first transparent adhesive layer TA1, the second transparent adhesive layer TA2, and the third transparent adhesive layer TA3; for example, an adhesive material containing a light-transmitting acrylic resin can be used. Furthermore, since the liquid crystal light control element 102 experiences a temperature rise due to heat radiated from the light source section 106, it is preferable that the coefficients of thermal expansion of the first transparent adhesive layer TA1, the second transparent adhesive layer TA2, and the third transparent adhesive layer TA3 have values ​​close to those of the first substrate and the second substrate.

[0053] However, the coefficients of thermal expansion of the first transparent adhesive layer TA1, the second transparent adhesive layer TA2, and the third transparent adhesive layer TA3 are, in most cases, higher than those of the glass substrate. Therefore, stress mitigation during temperature rise needs to be considered. To mitigate thermal stress during temperature rise, it is preferable that the thickness of the first transparent adhesive layer TA1, the second transparent adhesive layer TA2, and the third transparent adhesive layer TA3 is greater than the inter-cell gap (thickness of the liquid crystal layer) of each liquid crystal cell (first liquid crystal cell 10, second liquid crystal cell 20, third liquid crystal cell 30, and fourth liquid crystal cell 40).

[0054] As described below, the first liquid crystal unit 10, the second liquid crystal unit 20, the third liquid crystal unit 30, and the fourth liquid crystal unit 40 have substantially the same structure. The liquid crystal light control element 102 according to this embodiment has a structure in which the third liquid crystal unit 30 and the fourth liquid crystal unit 40 overlap with the first liquid crystal unit 10 and the second liquid crystal unit 20 after being rotated 90 degrees. In other words, the liquid crystal light control element 102 according to this embodiment has a structure including a plurality of liquid crystal units, and at least one liquid crystal unit and other liquid crystal units adjacent to (overlapping with) the at least one liquid crystal unit are arranged in a state after being rotated 90 degrees. It should be noted that in this embodiment, the third liquid crystal unit 30 and the fourth liquid crystal unit 40 are rotated 90 degrees with respect to the first liquid crystal unit 10 and the second liquid crystal unit 20, but this rotation angle can be set to a range of 90 ± 10 degrees.

[0055] exist Figure 2 In this configuration, based on the arrangement of the first liquid crystal cell 10 and the second liquid crystal cell 20, the third liquid crystal cell 30 and the fourth liquid crystal cell 40 are arranged in a state after being rotated 90 degrees. Conversely, based on the third liquid crystal cell 30 and the fourth liquid crystal cell 40, the first liquid crystal cell 10 and the second liquid crystal cell 20 can be said to be arranged in a state after being rotated within a 90-degree range. By overlapping multiple liquid crystal cells having the same electrode pattern and rotating a portion of these liquid crystal cells, a change in the electrode arrangement can be imposed, and a change in the diffusion of light passing through the stacked liquid crystal cells can be imposed. Details are explained below.

[0056] Figure 3 This is a perspective view illustrating the configuration of the liquid crystal light control element 102, showing the arrangement of electrodes disposed in each of the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40. It should be noted that, for ease of explanation, Figure 3 The diagram shows the X-axis, Y-axis, and Z-axis. In the following description, the X-axis direction refers to the direction along the X-axis, the Y-axis direction refers to the direction along the Y-axis, and the Z-axis direction refers to the direction along the Z-axis.

[0057] The first liquid crystal unit 10, the second liquid crystal unit 20, the third liquid crystal unit 30, and the fourth liquid crystal unit 40 are arranged overlappingly in the Z-axis direction. The actual liquid crystal light control element 102 is arranged with the liquid crystal units closely connected, but... Figure 3 For ease of explanation, the unfolded state of each liquid crystal cell is shown in the diagram.

[0058] The first liquid crystal unit 10 includes a first substrate S11 and a second substrate S12, a first electrode E11 and a second electrode E12, and a first liquid crystal layer LC1 between the first substrate S11 and the second substrate S12. The first electrode E11 is disposed between the first substrate S11 and the first liquid crystal layer LC1, and the second electrode E12 is disposed between the second substrate S12 and the first liquid crystal layer LC1. It should be noted that, as described above, the first substrate S11 and the second substrate S12 are opposite to each other; this opposing surface can also be defined as the inner surface, and the surface opposite to the inner surface can be defined as the outer surface. In this case, the first electrode E11 is disposed on the inner surface of the first substrate, and the second electrode E12 is disposed on the inner surface of the second substrate. The same applies to the second liquid crystal unit 20, the third liquid crystal unit 30, and the fourth liquid crystal unit 40 described below.

[0059] The first electrode E11 includes a plurality of first strip electrodes E11A and a plurality of second strip electrodes E11B formed in a strip shape. The second electrode E12 includes a plurality of third strip electrodes E12A and a plurality of fourth strip electrodes E12B formed in a strip shape. The plurality of first strip electrodes E11A and the plurality of second strip electrodes E11B are alternately arranged in a comb-like interlocking manner, and the plurality of third strip electrodes E12A and the plurality of fourth strip electrodes E12B are alternately arranged in a comb-like interlocking manner.

[0060] The long sides of a plurality of first strip electrodes E11A and a plurality of second strip electrodes E11B are arranged parallel to the Y-axis, and the long sides of a plurality of third strip electrodes E12A and a plurality of fourth strip electrodes E12B are arranged parallel to the X-axis. In other words, the plurality of first strip electrodes E11A and a plurality of second strip electrodes E11B are arranged with their long sides intersecting the plurality of third strip electrodes E12A and a plurality of fourth strip electrodes E12B. This intersection angle is preferably 90 ± 10 degrees, and more preferably 90 degrees (orthogonal).

[0061] The second liquid crystal unit 20 includes a first substrate S21 and a second substrate S22, a first electrode E21 and a second electrode E22, and a second liquid crystal layer LC2 between the first substrate S21 and the second substrate S22. The first electrode E21 is disposed between the first substrate S21 and the second liquid crystal layer LC2, and the second electrode E22 is disposed between the second substrate S22 and the second liquid crystal layer LC2.

[0062] The first electrode E21 includes a plurality of first strip electrodes E21A and a plurality of second strip electrodes E21B formed in a strip shape. The second electrode E22 includes a plurality of third strip electrodes E22A and a plurality of fourth strip electrodes E22B formed in a strip shape. The plurality of first strip electrodes E21A and the plurality of second strip electrodes E21B are alternately arranged in a comb-like interlocking manner, and the plurality of third strip electrodes E22A and the plurality of fourth strip electrodes E22B are alternately arranged in a comb-like interlocking manner.

[0063] The long sides of a plurality of first strip electrodes E21A and a plurality of second strip electrodes E21B are arranged parallel to the Y-axis, and the long sides of a plurality of third strip electrodes E22A and a plurality of fourth strip electrodes E22B are arranged parallel to the X-axis. In other words, the plurality of first strip electrodes E21A and a plurality of second strip electrodes E21B are arranged with their long sides intersecting the plurality of third strip electrodes E22A and a plurality of fourth strip electrodes E22B. This intersection angle is preferably 90 ± 10 degrees, and more preferably 90 degrees (orthogonal).

[0064] The third liquid crystal unit 30 includes a first substrate S31 and a second substrate S32, a first electrode E31 and a second electrode E32, and a third liquid crystal layer LC3 between the first substrate S31 and the second substrate S32. The first electrode E31 is disposed between the first substrate S31 and the third liquid crystal layer LC3, and the second electrode E32 is disposed between the second substrate S32 and the third liquid crystal layer LC3.

[0065] The first electrode E31 includes a plurality of first strip electrodes E31A and a plurality of second strip electrodes E31B formed in a strip shape. The second electrode E32 includes a plurality of third strip electrodes E32A and a plurality of fourth strip electrodes E32B formed in a strip shape. The plurality of first strip electrodes E31A and the plurality of second strip electrodes E31B are alternately arranged in a comb-like interlocking manner, and the plurality of third strip electrodes E32A and the plurality of fourth strip electrodes E32B are alternately arranged in a comb-like interlocking manner.

[0066] The long sides of a plurality of first strip electrodes E31A and a plurality of second strip electrodes E31B are arranged parallel to the X-axis, and the long sides of a plurality of third strip electrodes E32A and a plurality of fourth strip electrodes E32B are arranged parallel to the Y-axis. In other words, the plurality of first strip electrodes E31A and a plurality of second strip electrodes E31B are arranged with their long sides intersecting the plurality of third strip electrodes E32A and a plurality of fourth strip electrodes E32B. This intersection angle is preferably 90 ± 10 degrees, and more preferably 90 degrees (orthogonal).

[0067] The fourth liquid crystal unit 40 includes a first substrate S41 and a second substrate S42, a first electrode E41 and a second electrode E42, and a fourth liquid crystal layer LC4 between the first substrate S41 and the second substrate S42. The first electrode E41 is disposed between the first substrate S41 and the fourth liquid crystal layer LC4, and the second electrode E42 is disposed between the second substrate S42 and the fourth liquid crystal layer LC4.

[0068] The first electrode E41 includes a plurality of first strip electrodes E41A and a plurality of second strip electrodes E41B formed in a strip shape. The second electrode E42 includes a plurality of third strip electrodes E42A and a plurality of fourth strip electrodes E42B formed in a strip shape. The plurality of first strip electrodes E41A and the plurality of second strip electrodes E41B are alternately arranged in a comb-like interlocking manner, and the plurality of third strip electrodes E42A and the plurality of fourth strip electrodes E42B are alternately arranged in a comb-like interlocking manner.

[0069] The long sides of a plurality of first strip electrodes E41A and a plurality of second strip electrodes E41B are arranged parallel to the X-axis, and the long sides of a plurality of third strip electrodes E42A and a plurality of fourth strip electrodes E42B are arranged parallel to the Y-axis. In other words, the plurality of first strip electrodes E41A and a plurality of second strip electrodes E41B are arranged with their long sides intersecting the plurality of third strip electrodes E42A and a plurality of fourth strip electrodes E42B. This intersection angle is preferably 90 ± 10 degrees, and more preferably 90 degrees (orthogonal).

[0070] like Figure 3 As shown, in the liquid crystal light control element 102, the long side directions of the first strip electrode E11A and the second strip electrode E11B of the first liquid crystal unit 10 are arranged in the same direction as the long side directions of the first strip electrode E21A and the second strip electrode E21B of the second liquid crystal unit 20, and the long side directions of the first strip electrode E31A and the second strip electrode E31B of the third liquid crystal unit 30 are arranged in the same direction as the long side directions of the first strip electrode E41A and the second strip electrode E41B of the fourth liquid crystal unit 40.

[0071] Furthermore, the long side directions of the first strip electrode E11A and the second strip electrode E11B of the first liquid crystal unit 10 and the first strip electrode E21A and the second strip electrode E21B of the second liquid crystal unit 20 are arranged to intersect with the long side directions of the first strip electrode E31A and the second strip electrode E31B of the third liquid crystal unit 30 and the first strip electrode E41A and the second strip electrode E41B of the fourth liquid crystal unit 40. This intersection angle is preferably 90 ± 10 degrees, and more preferably 90 degrees (orthogonal).

[0072] Similarly, in the liquid crystal light control element 102, the long side directions of the third strip electrode E12A and the fourth strip electrode E12B of the first liquid crystal unit 10 are arranged in the same direction as the long side directions of the third strip electrode E22A and the fourth strip electrode E22B of the second liquid crystal unit 20, and the long side directions of the third strip electrode E32A and the fourth strip electrode E32B of the third liquid crystal unit 30 are arranged in the same direction as the long side directions of the third strip electrode E42A and the fourth strip electrode E42B of the fourth liquid crystal unit 40.

[0073] Furthermore, the long side directions of the third strip electrode E12A and the fourth strip electrode E12B of the first liquid crystal unit 10, and the third strip electrode E22A and the fourth strip electrode E22B of the second liquid crystal unit 20, are arranged to intersect with the long side directions of the third strip electrode E32A and the fourth strip electrode E32B of the third liquid crystal unit 30, and the third strip electrode E42A and the fourth strip electrode E42B of the fourth liquid crystal unit 40. This intersection angle is preferably 90 ± 10 degrees, and more preferably 90 degrees (orthogonal).

[0074] Thus, in the liquid crystal light control element 102 according to this embodiment, the first electrodes E11 and E21 of the first liquid crystal unit 10 and the second liquid crystal unit 20 have electrode shapes formed by arranging multiple strip-shaped patterns, with their long sides arranged in a direction parallel to the Y-axis direction. Furthermore, the first electrodes E31 and E41 of the third liquid crystal unit 30 and the fourth liquid crystal unit 40 have electrode shapes formed by arranging multiple strip-shaped patterns, with their long sides arranged in a direction parallel to the X-axis direction. In addition, the long side direction of the strip-shaped patterns of the first electrodes E11 and E21 of the first liquid crystal unit 10 and the second liquid crystal unit 20 intersects the long side direction of the strip-shaped patterns of the first electrodes E31 and E41 of the third liquid crystal unit 30 and the fourth liquid crystal unit 40. The intersection angle is preferably in the range of 90 ± 10 degrees, as described above, and more preferably orthogonal (90 degrees).

[0075] The first electrode E11 and second electrode E12 disposed in the first liquid crystal cell 10, the first electrode E21 and second electrode E22 disposed in the second liquid crystal cell 20, the first electrode E31 and second electrode E32 disposed in the third liquid crystal cell 30, and the first electrode E41 and second electrode E42 disposed in the fourth liquid crystal cell 40 have approximately the same size when viewed from above. Although Figure 3 Although not shown in the figure, the light source unit 106 is disposed on the lower side of the first liquid crystal cell 10. Light emitted from the light source unit 106 and incident on the liquid crystal light control element 102 passes through all of the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40 and is emitted out.

[0076] The first liquid crystal unit 10, the second liquid crystal unit 20, the third liquid crystal unit 30, and the fourth liquid crystal unit 40 have substantially the same structure. The first liquid crystal unit 10 will be described in more detail below as an example.

[0077] Figure 4A A top view of the first substrate S11 is shown. Figure 4B A top view of the second substrate S12 is shown. More specifically, Figure 4A A top view of the inner surface of the first substrate S11 is shown. Figure 4B A top view of the inner surface of the second substrate S12 is shown.

[0078] like Figure 4A As shown, a first electrode E11 is disposed on a first substrate S11. The first electrode E11 includes a plurality of first strip electrodes E11A and a plurality of second strip electrodes E11B. The plurality of first strip electrodes E11A and the plurality of second strip electrodes E11B have a strip-shaped pattern. Figure 4A As shown, a plurality of first strip electrodes E11A and a plurality of second strip electrodes E11B are spaced apart at a predetermined interval and are arranged alternately.

[0079] Multiple first strip electrodes E11A are respectively connected to a first power supply line PL11, and multiple second strip electrodes E11B are respectively connected to a second power supply line PL12. The first power supply line PL11 is connected to a first connection terminal T11, and the second power supply line PL12 is connected to a second connection terminal T12. The first connection terminal T11 and the second connection terminal T12 are disposed along one side of the end of the first substrate S11.

[0080] The third connection terminal T13 is disposed adjacent to the first connection terminal T11, and the fourth connection terminal T14 is disposed adjacent to the second connection terminal T12. The third connection terminal T13 is connected to the fifth power supply line PL15. The fifth power supply line PL15 is connected to the first power supply terminal PT11. The first power supply terminal PT11 is disposed at a predetermined position within the surface of the first substrate S11. The fourth connection terminal T14 is connected to the sixth power supply line PL16. The sixth power supply line PL16 is connected to the second power supply terminal PT12. The second power supply terminal PT12 is disposed at a predetermined position within the surface of the first substrate S11.

[0081] Different or the same voltages are applied to multiple first strip electrodes E11A connected to the first power supply line PL11 and multiple second strip electrodes E11B connected to the second power supply line PL12. When different voltage levels are applied to the multiple first strip electrodes E11A and multiple second strip electrodes E11B respectively, an electric field (transverse electric field) is generated due to the potential difference between the two electrodes.

[0082] like Figure 4BAs shown, the second electrode E12 is disposed on the second substrate S12. The second electrode E12 includes a plurality of third strip electrodes E12A and a plurality of fourth strip electrodes E12B. The plurality of third strip electrodes E12A and the plurality of fourth strip electrodes E12B have strip-shaped patterns. Figure 4B As shown, a plurality of third strip electrodes E12A and a plurality of fourth strip electrodes E12B are spaced apart by a specified interval and are arranged alternately.

[0083] Multiple third strip electrodes E12A are connected to the third power supply line PL13, and multiple fourth strip electrodes E12B are connected to the fourth power supply line PL14. The third power supply line PL13 is connected to the third power supply terminal PT13, and the fourth power supply line PL14 is connected to the fourth power supply terminal PT14. The third power supply terminal PT13 is located at a position corresponding to the first power supply terminal PT11 on the first substrate S11 side, and the fourth power supply terminal PT14 is located at a position corresponding to the second power supply terminal PT12 on the first substrate S11 side.

[0084] Different or the same voltages are applied to the multiple third strip electrodes E12A connected to the third power supply line PL13 and the multiple fourth strip electrodes E12B connected to the fourth power supply line PL14. When different voltage levels are applied to the multiple third strip electrodes E12A and the multiple fourth strip electrodes E12B respectively, an electric field (transverse electric field) is generated due to the potential difference between the two electrodes.

[0085] The first connection terminal T11, the second connection terminal T12, the third connection terminal T13, and the fourth connection terminal T14 disposed on the first substrate S11 are connected to a flexible wiring substrate (not shown). No terminals for connection to the flexible wiring substrate are disposed on the second substrate S12 side, but the third power supply terminal PT13 is electrically connected to the first power supply terminal PT11, and the fourth power supply terminal PT14 is electrically connected to the second power supply terminal PT12, through a conductive material.

[0086] Figure 5 Showing with Figure 4A and Figure 4B The cross-sectional structure of the first liquid crystal cell 10 corresponding to the A1-A2 line shown.

[0087] The first liquid crystal cell 10 has an effective region AA capable of polarizing and diffusing incident light. A first electrode E11 and a second electrode E12 are disposed within the effective region AA. The first substrate S11 and the second substrate S12 are disposed with the first electrode E11 and the second electrode E12 facing each other, and are bonded together by a sealing material SE disposed outside the effective region AA. The first liquid crystal layer LC1 is sandwiched between the first substrate S11 and the second substrate S12 and is formed in the region surrounded by the sealing material SE.

[0088] The first electrode E11 on the first substrate S11 side includes a first strip electrode E11A and a second strip electrode E11B, and the second electrode E12 on the second substrate S12 side includes a third strip electrode E12A and a fourth strip electrode E12B. Figure 5 The diagram shows that the long side directions of the first strip electrode E11A and the second strip electrode E11B are arranged to intersect with the long side directions of the third strip electrode E12A and the fourth strip electrode E12B.

[0089] A first alignment film AL11 is disposed on a first substrate S11, and a second alignment film AL12 is disposed on a second substrate S12. The first alignment film AL11 is disposed in such a way that it covers the first electrode E11, and the second alignment film AL12 is disposed in such a way that it covers the second electrode E12.

[0090] The first power supply terminal PT11 and the third power supply terminal PT13 are disposed on the outside of the sealing material SE. The first power supply terminal PT11 and the third power supply terminal PT13 are electrically connected via a first conductive component CP11. The first conductive component CP11 is formed of a conductive paste material, such as silver paste or carbon paste. It should be noted that although... Figure 5 Although not shown in the diagram, the second power supply terminal PT12 and the fourth power supply terminal PT14 are also electrically connected through conductive components.

[0091] The first substrate S11 and the second substrate S12 are light-transmitting substrates, such as glass substrates or resin substrates. The first electrode E11 and the second electrode E12 are transparent electrodes formed of transparent conductive materials such as indium tin oxide (ITO) and indium zinc oxide (IZO). The power supply lines (first power supply line PL11, second power supply line PL12, third power supply line PL13, fourth power supply line PL14, fifth power supply line PL15, and sixth power supply line PL16), the connection terminals (first connection terminal T11, second connection terminal T12, third connection terminal T13, and fourth connection terminal T14), and the power supply terminals (first power supply terminal PT11, second power supply terminal PT12, third power supply terminal PT13, and fourth power supply terminal PT14) are formed of metallic materials such as aluminum, titanium, molybdenum, and tungsten. It should be noted that the power supply lines (first power supply line PL11, second power supply line PL12, third power supply line PL13, fourth power supply line PL14, fifth power supply line PL15, and sixth power supply line PL16) can also be formed from the same transparent conductive film as the first electrode E11 and the second electrode E12. The first alignment film AL1 and the second alignment film AL2 are formed from horizontal alignment films having an alignment restraint force substantially parallel to the main plane of the substrate. The first liquid crystal layer LC1, for example, uses a twisted nematic liquid crystal (TN liquid crystal). It should be noted that although... Figure 5Although not shown in the figure, a spacer for maintaining a certain distance between the two substrates can also be provided between the first substrate S11 and the second substrate S12.

[0092] Next, refer to Figures 6A to 8 The electro-optic effect in the first liquid crystal unit 10 will be explained. It should be noted that... Figures 6A to 8 The diagram only illustrates the components required for explanation.

[0093] Figure 6A and Figure 6B A partial cross-sectional schematic structure of the first liquid crystal cell 10 is shown. Figure 6A The first alignment film AL11 on the first substrate S11 side and the second alignment film AL12 on the second substrate S12 side have different orientation directions. Specifically, the orientation direction ALD1 of the first alignment film AL11 faces the normal direction of the paper surface, and the orientation direction ALD2 of the second alignment film AL12 faces the left-right direction of the paper surface. The first electrode E11 includes a first strip electrode E11A and a second strip electrode E11B, whose long side direction is arranged orthogonal to the alignment direction ALD1. The second electrode E12 includes a third strip electrode E12A and a fourth strip electrode E12B, whose long side direction is arranged orthogonal to the alignment direction ALD2. It should be noted that the alignment treatment for the first alignment film AL1 and the second alignment film AL2 can be either a friction treatment or a photoalignment treatment. Furthermore, the angle at which the orientation direction ALD1 of the first orientation film AL1 intersects with the first strip electrode E11A and the second strip electrode E11B, and the angle at which the orientation direction ALD2 of the second orientation film AL2 intersects with the third strip electrode E12A and the fourth strip electrode E12B, are not limited to being orthogonal, and can be set within the range of 90 degrees ± 10 degrees.

[0094] TN liquid crystal is used as the first liquid crystal layer LC1. Since the orientation direction ALD1 of the first alignment film AL11 is orthogonal to the orientation direction ALD2 of the second alignment film AL12, the liquid crystal molecules of the first liquid crystal layer LC1 are aligned by twisting 90 degrees along the long axis of the liquid crystal molecules from the first alignment film AL11 to the second alignment film AL12 without being subjected to an external electric field. Figure 6A The diagram shows a state where no voltage is applied to the first strip electrode E11A and the second strip electrode E11B, and also shows a state where the long axis of the liquid crystal molecules is twisted by 90 degrees and oriented. Specifically, on the first alignment film AL11 side, the long axis of the liquid crystal molecules is aligned along the normal direction of the paper surface, and on the second alignment film AL12 side, the long axis of the liquid crystal molecules is aligned along the left-right direction of the paper surface.

[0095] It should be noted that, Figure 6AAn example is shown where the first liquid crystal layer LC1 is formed of a positive twisted nematic liquid crystal (TN liquid crystal), and the long axis of the liquid crystal molecules is aligned in the same direction as the alignment direction of the alignment film. However, by rotating the alignment direction of the alignment film by 90 degrees, that is, by making the alignment directions of each alignment film AL11, AL12 extend along the extension direction of the first electrode E11 of the first substrate S11 and the second electrode E12 of the second substrate S12, a negative liquid crystal can be used. Preferably, the liquid crystal contains a chiral agent that imparts twisting to the liquid crystal molecules.

[0096] Figure 6B The diagram illustrates a state where the first strip electrode E11A and the second strip electrode E11B are fixed at the same potential (e.g., ground potential), a low-level voltage VL is applied to the third strip electrode E12A, and a high-level voltage VH is applied to the fourth strip electrode E12B. In this state, no electric field is generated on the first substrate S11 side, but a transverse electric field is generated between the third strip electrode E12A and the fourth strip electrode E12B. Figure 6B As shown, the liquid crystal molecules on the second substrate S12 side are affected by the lateral electric field, causing their orientation direction to change. That is, the orientation change of the liquid crystal molecules on the second substrate S12 side is such that the long axis direction is parallel to the direction of the electric field.

[0097] The values ​​of the low-level voltage VL and the high-level voltage VH applied to the third strip electrode E12A and the fourth strip electrode E12B are appropriately set. For example, 0V is applied as the low-level voltage VL1, and a voltage of 5 to 30V is applied as the high-level voltage VH1. The low-level voltage VL and the high-level voltage VH are applied alternately to the third strip electrode E12A and the fourth strip electrode E12B. For example, as... Figure 6C As shown, the voltage can also be applied in a way that the voltage level between the two electrodes changes synchronously and periodically, such that during a certain period, a low voltage VL is applied to the third strip electrode E12A and a high voltage VH is applied to the fourth strip electrode E12B, and during the next certain period, a high voltage VH is applied to the third strip electrode E12A and a low voltage VL is applied to the fourth strip electrode E12B.

[0098] By alternately applying low-level voltage VL and high-level voltage VH to the third strip electrode E12A and the fourth strip electrode E12B, an alternating electric field can be generated, suppressing the degradation of the first liquid crystal layer LC1. It should be noted that the frequency of the voltage applied to the third strip electrode E12A and the fourth strip electrode E12B can be any frequency at which the liquid crystal molecules can follow the change in electric field, for example, a frequency in the range of 15–100 Hz. It should also be noted that the potential applied to the first strip electrode E11A and the second strip electrode E11B can be an intermediate potential between the aforementioned low-level voltage and high-level voltage.

[0099] Figure 7A This is a partial perspective view of the first liquid crystal cell 10, showing the first strip electrode E11A and the second strip electrode E11B, the first alignment film AL1, the third strip electrode E12A and the fourth strip electrode E12B, the second alignment film AL2, and the first liquid crystal layer LC1. Figure 7B and Figure 7C A cross-sectional schematic diagram of the first liquid crystal unit 10 is shown. Figure 7B Showing from Figure 7A View from side A shown Figure 7A The cross-sectional view of the first liquid crystal unit 10 shown is shown below. Figure 7C Showing from Figure 7A The diagram shows a cross-sectional view taken from side B. It should be noted that... Figure 7B and Figure 7C The orientation direction ALD1 of the first orientation film AL11 is shown to intersect with the orientation direction ALD2 of the second orientation film AL12.

[0100] like Figure 7B and Figure 7C As shown, the first strip electrode E11A and the second strip electrode E11B are arranged with a center-to-center distance W, and the third strip electrode E12A and the fourth strip electrode E12B are also arranged with a center-to-center distance W. This center-to-center distance W is relative to... Figure 7AThe width 'a' of the first strip electrode E11A and the distance 'b' from the end of the first strip electrode E11A to the end of the second strip electrode E11B have a relationship of W = a + b. Furthermore, the first strip electrode E11A and the second strip electrode E11B are spaced apart from the third strip electrode E12A and the fourth strip electrode E12B, and are arranged opposite each other in a mutually orthogonal state. The first substrate S11 and the second substrate S12 are arranged opposite each other at a distance D, which substantially corresponds to the thickness of the first liquid crystal layer LC1. In reality, the first strip electrode E11A and the first alignment film AL11 are provided on the first substrate S11, and the third strip electrode E12A and the second alignment film AL12 are provided on the second substrate S12, etc. However, the thickness of these electrodes and alignment films is sufficiently small compared to the size of the distance D, so the thickness of the first liquid crystal layer LC1 can be considered to be the same as the distance D.

[0101] In the first liquid crystal cell 10, the spacing D preferably has a size that is the same as or greater than the center-to-center distance W of the strip electrodes. That is, the spacing D preferably has a length that is more than one time the center-to-center distance W. For example, the spacing D preferably has a size that is more than two times the center-to-center distance W of the strip electrodes. When the width of the first strip electrode E11A is 5 μm, the width a of the first strip electrode E11A and the second strip electrode E11B is 5 μm, and the spacing b from the end of the first strip electrode E11A to the end of the second strip electrode E11B is 5 μm, the center-to-center distance W of the strip electrodes is 10 μm. In this case, the spacing D preferably has a size of 10 μm or more.

[0102] By making the center-to-center distance W of the strip electrodes have such a relationship with the aforementioned interval D, it is possible to suppress the mutual interference between the electric fields on the sides of the first strip electrode E11A and the second strip electrode E11B and the electric fields on the sides of the third strip electrode E12A and the fourth strip electrode E12B. That is, as Figure 7B and Figure 7C As shown, when the orientation of liquid crystal molecules located near the third strip electrode E12A and the fourth strip electrode E12B is controlled by the electric field generated between them, the orientation of liquid crystal molecules located near the first strip electrode E11A and the second strip electrode E11B can be unaffected.

[0103] Incidentally, it is known that the refractive index of liquid crystals varies depending on their orientation. For example... Figure 6AAs shown, in the OFF state where no electric field is applied to the first liquid crystal layer LC1, the long axis of the liquid crystal molecules is horizontally aligned on the surface of the substrate and oriented with a 90-degree twist from the first substrate S11 side to the second substrate S12 side. The liquid crystal layer LC1 has a substantially uniform refractive index distribution in this orientation state. Therefore, although the first polarization component (PL1) and the second polarization component (PL2) orthogonal to the first polarization component (PL1) of the light incident on the first liquid crystal cell 10 undergo optical rotation due to the initial orientation of the liquid crystal molecules, they pass through the first liquid crystal layer LC1 with almost no refraction (or scattering). Here, the first polarization component (PL1) corresponds to, for example, P-polarized light in natural light, and the second polarization component (PL2) corresponds to, for example, S-polarized light.

[0104] On the other hand, such as Figure 6B As shown, in the ON state, where an electric field is formed by applying a voltage to the third strip electrode E12A and the fourth strip electrode E12B, and given that the first liquid crystal layer LC1 has a positive dielectric anisotropy, the liquid crystal molecules are aligned along the electric field with their long axes aligned with the electric field. As a result, as... Figure 6B As shown, there are regions where liquid crystal molecules stand approximately vertically above the third strip electrode E12A and the fourth strip electrode E12B, regions where they are tilted and oriented along the distribution of the electric field between the third strip electrode E12A and the fourth strip electrode E12B, and regions where the initial orientation is maintained in regions away from the third strip electrode E12A and the fourth strip electrode E12B.

[0105] like Figure 6B As shown, between the third strip electrode E12A and the fourth strip electrode E12B, the long axis of the liquid crystal molecules is oriented in a convex arc shape along the direction of the electric field generation. That is, as... Figure 6A and Figure 6B As shown, the initial orientation of the liquid crystal molecules is the same as the direction of the transverse electric field generated between the third strip electrode E12A and the fourth strip electrode E12B, as... Figure 6B As schematically shown, the orientation of the liquid crystal molecules located approximately at the center between the two electrodes remains almost unchanged. However, the liquid crystal molecules located from the center to each electrode side are tilted towards the normal direction relative to the surface of the second substrate S12 according to the distribution of the electric field intensity. Therefore, between the third strip electrode E12A and the fourth strip electrode E12B, the liquid crystal molecules are oriented in an arc shape.

[0106] For reference Figure 7B and Figure 7C As explained, since the thickness of the liquid crystal layer LC1 is sufficiently thick, even if the orientation of the liquid crystal molecules on the second substrate S12 side changes, the liquid crystal molecules on the first substrate S11 side maintain their initial orientation.

[0107] Liquid crystal molecules exhibit refractive index anisotropy Δn. Therefore, the first liquid crystal layer LC1 in the conductive state has a refractive index distribution or retardation distribution corresponding to the orientation state of the liquid crystal molecules. Here, the retardation is represented by Δn·d when the thickness of the first liquid crystal layer LC1 is set to d. In the conductive state, the first polarization component PL1 diffuses as it passes through the first liquid crystal layer LC1 due to the influence of the refractive index distribution of the first liquid crystal layer LC1. Because an arc-shaped dielectric constant distribution is formed in the liquid crystal layer LC1, the incident light (the polarization component parallel to the initial orientation direction of the liquid crystal molecules) diffuses radially.

[0108] Figure 8 The phenomenon of the first polarization component PL1 and the second polarization component PL2 being diffused by the liquid crystal layer is schematically shown. Here, the X, Y, and Z axes used for illustration are positioned in the following directions. Figure 8 The relationship shown. That is, in Figure 8 In the diagram, the X-axis is located in the left-right direction of the paper, the Y-axis is located in the normal direction of the paper, and the Z-axis is located in the up-down direction of the paper.

[0109] Figure 8 The diagram illustrates the stacked state of the first liquid crystal cell 10 and the second liquid crystal cell 20. It shows the first substrate S11, S21, the second substrate S12, S22, the first strip electrodes E11A, E21A, the second strip electrodes E11B, E21B, the first alignment films AL11, AL21, the second alignment films AL12, AL22, the first liquid crystal layer LC1, and the second liquid crystal layer LC2 for each liquid crystal cell. The first transparent adhesive layer TA1 disposed between the first liquid crystal cell 10 and the second liquid crystal cell 20 is omitted here.

[0110] It should be noted that the long sides of the first strip electrode E11A and the second strip electrode E11B of the first liquid crystal unit 10, and the first strip electrode E21A and the second strip electrode E21B of the second liquid crystal unit 20 are arranged in the X-axis direction, while the long sides of the third strip electrode E12A and the fourth strip electrode E12B of the first liquid crystal unit 10, and the third strip electrode E22A and the fourth strip electrode E22B of the second liquid crystal unit 20 are aligned along the Y-axis direction. Furthermore, the alignment direction ALD1 of the first alignment films AL11 and AL21 is the same as the Y-axis direction, and the alignment direction ALD2 of the second alignment films AL12 and AL22 is the same as the X-axis direction. Therefore, the liquid crystal molecules of the first liquid crystal layer LC1 and the second liquid crystal layer LC2, whose alignment directions are limited by the alignment films, are aligned with their long axes pointing towards the Y-axis direction on the first substrate S11 and S21 side, and with their long axes pointing towards the X-axis direction on the second substrate S12 and S22 side.

[0111] Figure 8The diagram schematically illustrates the process from the entry of light containing a first polarization component PL1 and a second polarization component PL2 into the first liquid crystal cell 10 and its exit from the second liquid crystal cell 20. Here, the polarization axis of the first polarization component PL1 is in the same direction as the X-axis, and the polarization axis of the second polarization component PL2 is in the same direction as the Y-axis. In other words, the polarization axis of the first polarization component PL1 is orthogonal to the orientation direction ALD1 of the first alignment films AL11 and AL21, and parallel to the orientation direction ALD2 of the second alignment films AL12 and AL22; the polarization axis of the second polarization component PL2 is parallel to the orientation direction ALD1 of the first alignment films AL11 and AL21, and orthogonal to the orientation direction ALD2 of the second alignment films AL12 and AL22.

[0112] Figure 8 The diagram shows a state in the first liquid crystal cell 10 where the first strip electrode E11A and the second strip electrode E11B have the same potential (or the same voltage is applied to both strip electrodes), and a low-level voltage VL is applied to one of the third strip electrode E12A and the fourth strip electrode E12B while a high-level voltage VH is applied to the other. The second liquid crystal cell 20 is similarly shown in a state where the first strip electrode E21A and the second strip electrode E21B have the same potential (or the same voltage is applied to both strip electrodes), and a low-level voltage VL is applied to one of the third strip electrode E22A and the fourth strip electrode E22B while a high-level voltage VH is applied to the other.

[0113] Due to the electric field generated by the third strip electrode E12A and the fourth strip electrode E12B of the first liquid crystal cell 10, regions where liquid crystal molecules stand vertically on the second substrate S12 side of the first liquid crystal layer LC1 are formed, regions where they are tilted along the distribution of the electric field, and regions where the initial orientation is maintained are formed. Similarly, due to the electric field generated by the third strip electrode E22A and the fourth strip electrode E22B of the second liquid crystal cell 20, regions where liquid crystal molecules stand vertically on the second substrate S22 side of the second liquid crystal layer LC2 are formed, regions where they are tilted along the distribution of the electric field, and regions where the initial orientation is maintained are formed. On the other hand, the liquid crystal molecules on the first substrate S11 side of the first liquid crystal cell 10 and the liquid crystal molecules on the first substrate S21 side of the second liquid crystal cell 20 maintain their initial orientation.

[0114] Next, the effects of the first polarization component PL1 and the second polarization component PL2 on the first liquid crystal cell 10 and the second liquid crystal cell 20 in such a state will be explained.

[0115] The first polarization component PL1 incident on the first liquid crystal cell 10 undergoes optical rotation under the action of the first liquid crystal layer LC1, and the polarization axis changes from the X-axis direction to the Y-axis direction (or, in other words, the first polarization component PL1 changes to the second polarization component PL2). The first liquid crystal layer LC1 on the second substrate S12 side is affected by the transverse electric field formed by the third strip electrode E12A and the fourth strip electrode E12B, as shown in the reference... Figure 7C As explained, the long axis of the liquid crystal molecules is oriented in a convex arc shape. However, the polarization axis of the polarization component that rotates from the first polarization component PL1 to the second polarization component PL2 is in the Y-axis direction, while the orientation direction of the liquid crystal molecules on the second substrate S12 side is in the X-axis direction. Therefore, this polarization component passes through the first liquid crystal layer LC1 without diffusion.

[0116] The polarization component PL2, which undergoes a 90-degree rotation of its polarization axis by passing through the first liquid crystal cell 10, becomes the second polarization component PL1 when passing through the second liquid crystal cell 20. This polarization component is then subjected to the action of the second liquid crystal layer LC2, causing its polarization axis to rotate again by 90 degrees. In the second liquid crystal cell 20, the long axes of the liquid crystal molecules on the second substrate S22 side of the second liquid crystal layer LC2 are oriented in a convex arc shape. Since the second liquid crystal layer LC2 has a refractive index distribution corresponding to the orientation state of the liquid crystal molecules, the polarization component in the same direction as the orientation direction of the liquid crystal molecules diffuses towards the X-axis direction according to the change in the refractive index distribution of the liquid crystal molecules. That is, the polarization axis of the polarization component that rotates from the second polarization component PL2 to the first polarization component PL1 is in the X-axis direction, and the orientation direction of the liquid crystal molecules on the second substrate S22 side is also in the X-axis direction. Therefore, this polarization component diffuses towards the X-axis direction when passing through the second liquid crystal layer LC2.

[0117] On the other hand, the second polarization component PL2 incident on the first liquid crystal cell 10 undergoes optical rotation under the action of the first liquid crystal layer LC1, and its polarization axis changes from the Y-axis direction to the X-axis direction (or, in other words, the second polarization component PL2 changes into the first polarization component PL1). The first liquid crystal layer LC1 is affected by the transverse electric field formed by the third strip electrode E12A and the fourth strip electrode E12B on the second substrate S12 side, causing the long axis of the liquid crystal molecules to be oriented in a convex arc shape. Since the first liquid crystal layer LC1 has a refractive index distribution corresponding to the orientation state of the liquid crystal molecules, the polarization component in the same direction as the orientation direction of the liquid crystal molecules diffuses towards the X-axis direction according to the change in the refractive index distribution of the liquid crystal molecules. That is, the polarization axis of the polarization component that rotates from the second polarization component PL2 into the first polarization component PL1 is in the same X-axis direction as the orientation direction of the long axis of the liquid crystal molecules on the second substrate S12 side. Therefore, this polarization component diffuses towards the X-axis direction on the second substrate S12 side when passing through the first liquid crystal layer LC1.

[0118] The polarization component that changes from the second polarization component PL2 to the first polarization component PL1 by undergoing a 90-degree optical rotation of its polarization axis through the first liquid crystal cell 10, is then subjected to the action of the second liquid crystal layer LC2 when passing through the second liquid crystal cell 20. Its polarization axis rotates again by 90 degrees, becoming the second polarization component PL2. In the second liquid crystal cell 20, the long axis of the liquid crystal molecules on the second substrate S22 side of the second liquid crystal layer LC2 is oriented in a convex arc shape. The polarization axis of the polarization component that rotates from the first polarization component PL1 to the second polarization component PL2 through the second liquid crystal layer LC2 is in the Y-axis direction, while the orientation direction of the liquid crystal molecules on the second substrate S22 side is in the X-axis direction. Therefore, this polarization component passes through the second liquid crystal layer LC2 without diffusion.

[0119] Thus, the first polarization component PL1 undergoes two optical rotations when passing through the first liquid crystal cell 10 and the second liquid crystal cell 20, and diffuses once in the X-axis direction on the side of the second substrate S22. The second polarization component PL2 undergoes two optical rotations when passing through the first liquid crystal cell 10 and the second liquid crystal cell 20, and diffuses once in the X-axis direction on the side of the second substrate S12. In other words, the first polarization component PL1 and the second polarization component PL2 do not diffuse on the sides of the first substrates S11 and S21, but after optical rotation through the liquid crystal layer, they diffuse in the X-axis direction on the side of the second substrate S12 or the second substrate S22.

[0120] In this way, by causing each polarization component to diffuse after optical rotation through the liquid crystal layer, light loss during optical rotation can be reduced. In other words, by preventing each polarization component from diffusing before optical rotation, optical rotation occurring in the diffused state can be eliminated, light loss during optical rotation can be reduced, and the shape disorder of the light distribution pattern can be suppressed.

[0121] As clearly demonstrated above, by stacking two liquid crystal cells with identical structures and changing the polarization direction of light passing through these two liquid crystal cells twice, it is possible to achieve a state where the polarization direction remains unchanged before and after incident. On the other hand, by forming a convex arc-shaped refractive index distribution on the second substrate side (opposite to the light incident side) of each liquid crystal cell, the transmitted light can be diffused. Specifically, the first liquid crystal cell 10 can diffuse the light with the second polarization component PL2 in the X-axis direction after optical rotation, and the second liquid crystal cell 20 can diffuse the light with the first polarization component PL1 in the X-axis direction after optical rotation. That is, by stacking the first liquid crystal cell 10 and the second liquid crystal cell 20 and forming a refractive index distribution on the liquid crystal layer on the second substrate side (opposite to the light incident side) of each liquid crystal cell, light can be diffused without changing the polarization state.

[0122] As described above, by stacking two liquid crystal cells with the same structure, the polarization direction of the incident light can be changed twice, ensuring that the polarization direction remains unchanged before and after passing through the two liquid crystal cells. On the other hand, by applying a transverse electric field to the substrate on the side of the liquid crystal layer opposite to the light incident side to form a refractive index distribution, the transmitted light can be refracted in a specific direction. More specifically, the first liquid crystal cell 10 can diffuse the light with the second polarization component PL2 in the X-axis direction after optical rotation, and the second liquid crystal cell 20 can diffuse the light with the first polarization component PL1 in the X-axis direction after optical rotation.

[0123] In this way, the first polarization component PL1 of the incident light passing through the first liquid crystal layer LC1 and the second liquid crystal layer LC2 is diffused by the second liquid crystal layer LC2, and the second polarization component PL2 is diffused by the first liquid crystal layer LC1. Furthermore, the incident light passing through the first liquid crystal layer LC1 and the second liquid crystal layer LC2 undergoes a 90-degree optical rotation in both layers. In other words, the second polarization component PL2 of the incident light containing the first polarization component PL1 and the second polarization component PL2 is diffused in the first liquid crystal cell 10, and the first polarization component PL1 is diffused in the second liquid crystal cell 20. That is, by overlapping the first liquid crystal cell 10 and the second liquid crystal cell 20, the diffusion of specific polarization components can be controlled individually, and the light distribution of the light emitted from the light source can be controlled.

[0124] It should be noted that, Figure 3 An example of a strip electrode with the same configuration for the first electrode E11 and the second electrode E12 is shown for the first liquid crystal cell 10, but the configuration of the first electrode E11 is not limited to this example. For example, as Figure 9 As shown, the first electrode E11 can also be formed by a plate-shaped electrode (solide electrode) that corresponds to approximately the entire surface of the first liquid crystal layer LC1. The same applies to the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40. In the liquid crystal light control element 102 according to this embodiment, since a convex arc-shaped refractive index distribution is not formed by the first electrode disposed on the light incident side, the same effect can be obtained even if the first electrode is formed by a plate-shaped electrode (solide electrode).

[0125] Incidentally, it is known that light refracts at the boundary of different media, but the angle of refraction varies depending on the wavelength of the light. When light is incident on a liquid crystal layer with a refractive index distribution, since the angle of refraction is different for each wavelength, color disorder can sometimes be visually observed at the periphery of the light distribution pattern formed by passing light through the liquid crystal light control element 102, depending on the type of light source and the distance from the irradiated object.

[0126] In response to this, such as Figure 3 and Figure 9 As shown, the liquid crystal light control element 102 of this embodiment overlaps four liquid crystal cells in the light path of the light source, and arranges at least two of the four liquid crystal cells by rotating them 90 degrees relative to the other liquid crystal cells, thereby suppressing color disorder. That is, the liquid crystal light control element 102 of this embodiment can not only reduce light loss during light rotation and suppress disorder of the light distribution pattern, but also suppress color disorder of the light distribution pattern.

[0127] Hereinafter, the structure and operation of the liquid crystal light control element 102 according to one embodiment of the present invention will be described in detail in several embodiments.

[0128] First implementation method:

[0129] Figure 10 This illustration shows the arrangement of strip electrodes in each liquid crystal cell of the liquid crystal light control element 102 according to the first embodiment, and how the polarization state and diffusion pattern of incident light are controlled by each liquid crystal cell. In this embodiment, the arrangement of electrodes in the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40 is similar to... Figure 3 The structure shown is the same.

[0130] In the liquid crystal light control element 102, the liquid crystals of the first liquid crystal unit 10 and the second liquid crystal unit 20 have the same orientation direction. The long sides of the strip electrodes (E11A, E11B, E21A, E21B) in the first electrodes E11 and E21 are oriented in the same direction. The long sides of the strip electrodes (E12A, E12B, E22A, E22B) in the second electrodes E12 and E22 that intersect these electrodes are also oriented in the same direction. Furthermore, the liquid crystals of the third liquid crystal unit 30 and the fourth liquid crystal unit 40 have the same orientation direction. The long sides of the strip electrodes (E31A, E31B, E41A, E41B) in the first electrodes E31 and E41 are oriented in the same direction. The long sides of the strip electrodes (E32A, E32B, E42A, E42B) in the second electrodes E32 and E42 that intersect these electrodes are also oriented in the same direction. Furthermore, the long side direction of the strip electrodes (E12A, E12B, E22A, E22B) of the second electrodes E12 and E22 in the first liquid crystal unit 10 and the second liquid crystal unit 20 intersects the long side direction of the strip electrodes (E32A, E32B, E42A, E42B) of the second electrodes E32 and E42 in the third liquid crystal unit 30 and the fourth liquid crystal unit 40 at an angle of 90 degrees.

[0131] Furthermore, the extension directions of the first electrode (E11, E21, E31, E41) and the second electrode (E12, E22, E32, E42) of each liquid crystal cell are orthogonal to each other. (The following will be discussed further.) Figure 13 , Figure 14 as well as Figure 15 The illustrated implementation is the same. It should be noted that a configuration can also be adopted in which the third liquid crystal cell 30 and the fourth liquid crystal cell 40 are stacked relative to the first liquid crystal cell 10 and the second liquid crystal cell 20 in a state of rotation within a range of 90 degrees ± 10 degrees. Alternatively, a configuration can be adopted in which the extending directions of the first electrodes (E11, E21, E31, E41) and the second electrodes (E12, E22, E32, E42) of each liquid crystal cell are set within a range of 90 degrees ± 10 degrees.

[0132] Figure 10 The diagram shows the arrangement of electrodes in the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40, the orientation direction of the alignment film (arrows), and the initial orientation of the liquid crystal molecules. The liquid crystal layer is formed from positive liquid crystals. In the initial state, without inputting control signals to each liquid crystal cell, the long axis of the liquid crystal is aligned in a direction intersecting (orthogonal) with the strip-shaped electrodes. That is, the orientation direction of the alignment film (first alignment film) on the first substrate S11, S21, S31, and S41 sides of the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40 is arranged to intersect the long side direction of the first electrodes E11, E21, E31, and E41 with strip-shaped patterns; and the orientation direction of the alignment film (second alignment film) on the second substrate S12, S22, S32, and S42 sides is arranged to intersect the long side direction of the second electrodes E12, E22, E32, and E42 with strip-shaped patterns.

[0133] according to Figure 10In the configuration shown, the alignment films (not shown) on the first substrates S11 and S21 sides of the first liquid crystal cell 10 and the second liquid crystal cell 20 are aligned in a direction parallel to the X-axis, and the alignment films (not shown) on the second substrates S12 and S22 sides are aligned in a direction parallel to the Y-axis. Therefore, the long side direction of the strip patterns of the first electrodes E11 and E21 of the first liquid crystal cell 10 and the second liquid crystal cell 20 is aligned in a direction parallel to the Y-axis, and the long side direction of the strip patterns of the second electrodes E12 and E22 is aligned in a direction parallel to the X-axis. Furthermore, the alignment films (not shown) on the first substrates S31 and S41 sides of the third liquid crystal cell 30 and the fourth liquid crystal cell 40 are aligned in a direction parallel to the Y-axis, and the alignment films (not shown) on the second substrates S32 and S42 sides are aligned in a direction parallel to the X-axis. Therefore, the long side direction of the strip patterns of the first electrodes E31 and E41 of the third liquid crystal unit 30 and the fourth liquid crystal unit 40 is oriented parallel to the X-axis direction, and the long side direction of the strip patterns of the second electrodes E32 and E42 is oriented parallel to the Y-axis direction. It should be noted that in this embodiment, the orientation direction of the alignment film is set to 90 degrees relative to the extending direction of the electrode with the strip pattern, according to the definitions of the X-axis and Y-axis directions, but it can also be set to 90 ± 10 degrees.

[0134] In the following description, the direction with the same polarization direction as the first polarization component PL1 is defined as the Y-axis direction, and the direction with the same polarization direction as the second polarization component PL2 is defined as the X-axis direction. Additionally, Figure 10 The table shows (diffuse light 1X) indicating that the polarization component diffuses 1 degree in the X-axis direction up to this position, and (diffuse light 1X1Y) indicating that the polarization component diffuses 1 degree in both the X-axis and Y-axis directions up to this position. For Figures 12 to 15 The same applies.

[0135] Figure 10 The electrodes that form the transverse electric field are represented by shaded lines. Additionally, in Figure 10A table is inserted here, using terms such as transmission, optical rotation, and diffusion to represent the state of each polarization component when light containing the first polarization component PL1 and the second polarization component PL2 passes through the first electrode, liquid crystal layer, and second electrode of each liquid crystal cell. Here, "transmission" means that the polarization component passes through without diffusion or optical rotation. "Optical rotation" means that the polarization direction of the polarization component changes by 90 degrees. "Diffusion" means that the polarization component diffuses due to the influence of the refractive index distribution of the liquid crystal molecules. Therefore, in the table, for example, "transmission" marked at the first electrode indicates that the above-mentioned "transmission" phenomenon occurs near the first electrode of the liquid crystal layer. Furthermore, "optical rotation" marked at the liquid crystal layer indicates that the polarization direction of the polarization component changes by 90 degrees as it moves from the first substrate side to the second substrate side within the liquid crystal layer.

[0136] The liquid crystal light control element 102 is provided with a first liquid crystal unit 10, a second liquid crystal unit 20, a third liquid crystal unit 30, and a fourth liquid crystal unit 40 arranged sequentially from the light incident side. The light incident on the liquid crystal light control element 102 includes a first polarization component PL1 and a second polarization component PL2 orthogonal to the first polarization component PL1.

[0137] like Figure 10 As shown, the long sides of the second electrode E12 of the first liquid crystal cell 10 and the second electrode E22 of the second liquid crystal cell 20 are arranged in the same direction, which enables the first polarization component PL1 to diffuse in the Y-axis direction. Furthermore, the long sides of the second electrode E32 of the third liquid crystal cell 30 and the second electrode E42 of the fourth liquid crystal cell 40 are arranged in the same direction, which enables the second polarization component PL2 to diffuse in the X-axis direction.

[0138] In order for the liquid crystal light control element 102 to control the polarization and diffusion state of the incident light, a control signal is input to each liquid crystal cell. Figure 11 This is an example of the waveform of the control signal applied to the electrodes of each liquid crystal cell. Input is given to each liquid crystal cell. Figure 11The control signal is any one of the control signals A, B, and E shown. In control signals A and B, VL1 refers to a low-level voltage, and VH1 refers to a high-level voltage. For example, VL1 is 0V or -15V, and VH1 (relative to 0V) is 30V or (relative to -15V) is 15V. Control signal A is synchronized with control signal B. When control signal A is at the VL1 level, control signal B is at the VH1 level; when control signal A changes to the VH1 level, control signal B changes to the VL1 level. The period of control signals A and B is approximately 15-100Hz. On the other hand, control signal E is a signal with a fixed voltage. For example, control signal E is the intermediate voltage between VL1 and VH1. When VL1 = 0V and VH1 = 30V, VE = 15V; when VL1 = -15V and VH1 = +15V, VE = 0V.

[0139] The liquid crystal light control device 100 can control the light distribution pattern of the light emitted from the light source unit (106) into various patterns by selecting the control signal applied to each liquid crystal cell of the liquid crystal light control element 102. This embodiment shows an example of controlling the light emitted from the light source unit (106) into a quadrilateral light distribution pattern by the liquid crystal light control element 102.

[0140] Table 1 shows the... Figure 10 The control signals applied to each liquid crystal cell of the liquid crystal light control element 102 shown are illustrated. It should be noted that the control signals A, B, and E shown in Table 1 are... Figure 11 The control signals shown correspond to those shown.

[0141] [Table 1]

[0142]

[0143] like Figure 10 As shown in Table 1, control signals are input to each liquid crystal cell of the liquid crystal light control element 102. Control signal E is input to the first strip electrode E11A and the second strip electrode E11B of the first liquid crystal cell 10, control signal A is input to the third strip electrode E12A, and control signal B is input to the fourth strip electrode E12B. As shown in Table 1, control signals A, B, and E are also input to the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40 in the same manner as to the first liquid crystal cell 10. That is, in Figure 10 In the liquid crystal light control element 102 shown, a control signal E is applied to the first electrode of each liquid crystal cell, and control signals A and B are applied to the second electrode, generating a transverse electric field only on the second substrate side.

[0144] When the liquid crystal light control element 102 operates, the control signals shown in Table 1 are input to each strip electrode of each liquid crystal cell. When the control signals shown in Table 1 are input to the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40, as follows: Figure 7C As shown, the liquid crystal molecules on the second substrate side of each liquid crystal cell change their orientation state due to the influence of the lateral electric field.

[0145] exist Figure 10 In this context, focusing on the first polarization component PL1, the polarization axis of the first polarization component PL1 incident on the first liquid crystal cell 10 is in a direction that intersects (orthogonal to) the long axis direction of the liquid crystal molecules on the first substrate S11 side of the first liquid crystal layer LC1. Since the first electrode E11 does not generate a lateral electric field, the first polarization component PL1 is directed towards the second substrate S12 side without diffusion. Furthermore, the first polarization component PL1 rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it moves from the first substrate S11 side to the second substrate S12 side in the first liquid crystal layer LC1. Thus, the first polarization component PL1 transforms into the second polarization component PL2. On the second substrate S12 side, the second electrode E12 generates a lateral electric field, but the polarization axis of the second polarization component PL2 is in a direction that intersects the long axis direction of the liquid crystal molecules on the second substrate S12 side. Therefore, although the refractive index distribution of the liquid crystal molecules on the second substrate S12 side changes due to the electric field generated by the second electrode E12, the second polarization component PL2 is unaffected and transmits as is. That is, the first polarization component PL1 is transformed into the second polarization component PL2 during the process of passing through the first liquid crystal cell 10, and on the other hand, it is emitted from the second substrate S12 side without diffusion or the like.

[0146] Then, the second polarization component PL2 emitted from the first liquid crystal cell 10 is incident on the second liquid crystal cell 20. The polarization axis of the second polarization component PL2 is parallel to the long axis of the liquid crystal molecules on the first substrate S21 side of the second liquid crystal layer LC2. However, since the first electrode E21 does not generate a lateral electric field, the second polarization component PL2 proceeds to the second substrate S22 side without diffusion. In addition, the second polarization component PL2 rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it moves from the first substrate S21 side to the second substrate S22 side in the second liquid crystal layer LC2. As a result, the second polarization component PL2 transforms into the first polarization component PL1. Here, the polarization axis of the first polarization component PL1 is parallel to the long axis of the liquid crystal molecules on the second substrate S22 side. Due to the change in refractive index distribution of the liquid crystal molecules on the second substrate S22 side caused by the lateral electric field generated by the second electrode E22, the first polarization component PL1 diffuses in the Y-axis direction and is then emitted from the second liquid crystal cell 20. That is, the second polarization component PL2 incident on the second liquid crystal cell 20 is transformed into the first polarization component PL1 during the process of passing through the second liquid crystal cell 20 and diffuses in the Y-axis direction.

[0147] Thus, the first polarization component PL1 in the incident light temporarily transforms into the second polarization component PL2 before it is incident on the first liquid crystal cell 10 and emitted from the second liquid crystal cell 20, and then transforms back into the first polarization component PL1, and diffuses once in the Y-axis direction in the second liquid crystal cell 20.

[0148] In the third liquid crystal cell 30, the long side of the first electrode E31 intersects the first electrode E11 of the first liquid crystal cell 10 and the first electrode E21 of the second liquid crystal cell 20 at a 90-degree angle, and the long side of the second electrode E32 intersects the second electrode E12 of the first liquid crystal cell 10 and the second electrode E22 of the second liquid crystal cell 20 at a 90-degree angle. Similarly, in the fourth liquid crystal cell 40, the long side of the first electrode E41 intersects the first electrode E11 of the first liquid crystal cell 10 and the first electrode E21 of the second liquid crystal cell 20 at a 90-degree angle, and the long side of the second electrode E42 intersects the second electrode E12 of the first liquid crystal cell 10 and the second electrode E22 of the second liquid crystal cell 20 at a 90-degree angle. Therefore, in these third and fourth liquid crystal cells, the phenomena generated in the first liquid crystal cell 10 and the second liquid crystal cell 20 for each polarization component are reversed. It should be noted that this intersection angle can be set within the range of 90 ± 10 degrees.

[0149] When the first polarization component PL1 (diffuse light 1Y) passes through the second liquid crystal cell 20 and diffuses once in the Y-axis direction, it is incident on the third liquid crystal cell 30. The polarization axis of the first polarization component PL1 (diffuse light 1Y) is parallel to the long axis of the liquid crystal molecules on the first substrate S31 side of the third liquid crystal layer LC3. However, since the first electrode E31 does not generate a lateral electric field, the first polarization component PL1 (diffuse light 1Y) incident on the third liquid crystal cell 30 does not diffuse. In the third liquid crystal layer LC3, as it moves from the first substrate S31 side to the second substrate S32 side, it rotates 90 degrees according to the twisted orientation of the liquid crystal molecules. Thus, the first polarization component PL1 (diffuse light 1Y) transforms into the second polarization component PL2 (diffuse light 1Y). Here, the polarization axis of the second polarization component PL2 (diffuse light 1Y) is parallel to the long axis of the liquid crystal molecules on the second substrate S32 side. The refractive index distribution of the liquid crystal molecules on the second substrate S32 side changes due to the lateral electric field generated by the second electrode E32. Therefore, the second polarization component PL2 (diffuse light 1Y) diffuses in the X-axis direction and is then emitted from the third liquid crystal cell 30. That is, the first polarization component PL1 (diffuse light 1Y) incident on the third liquid crystal cell 30 is transformed into the second polarization component PL2 and diffuses in the X-axis direction (diffuse light 1X1Y) as it passes through the third liquid crystal cell 30.

[0150] The polarization axis of the second polarization component PL2 (diffuse light 1X1Y) emitted from the third liquid crystal cell 30 and incident on the fourth liquid crystal cell 40 is oriented in a direction intersecting the long axis direction of the liquid crystal molecules on the first substrate S41 side of the fourth liquid crystal layer LC4. However, since the first electrode E41 does not generate a lateral electric field, the second polarization component PL2 (diffuse light 1X1Y) incident on the fourth liquid crystal cell 40 does not diffuse. Instead, it rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it travels from the first substrate S41 side to the second substrate S42 side in the fourth liquid crystal layer LC4. Thus, the second polarization component PL2 (diffuse light 1X1Y) transforms into the first polarization component PL1 (diffuse light 1X1Y). Furthermore, the polarization axis of the first polarization component PL1 (diffuse light 1X1Y) is oriented in a direction intersecting the long axis direction of the liquid crystal molecules on the second substrate S42 side. Therefore, although the refractive index distribution of the liquid crystal molecules on the second substrate S42 side changes due to the lateral electric field generated by the second electrode E42, the first polarization component PL1 (diffuse light 1X1Y) is transmitted as is without being affected. That is, the second polarization component PL2 (diffuse light 1X1Y) transforms into the first polarization component PL1 (diffuse light 1X1Y) during its passage through the fourth liquid crystal cell 40, and on the other hand, it is emitted from the fourth liquid crystal cell 40 without diffusion or the like.

[0151] Thus, the first polarization component PL1 (diffuse light 1Y) incident on the third liquid crystal cell 30 rotates by 90 degrees in the third liquid crystal layer LC3 and the fourth liquid crystal layer LC4 until it is emitted from the fourth liquid crystal cell 40, and diffuses in the X-axis direction in the third liquid crystal cell 30, and is emitted from the fourth liquid crystal cell 40 as the first polarization component PL1 (diffuse light 1X1Y).

[0152] Therefore, during the period from the incident on the first liquid crystal cell 10 to the emission from the fourth liquid crystal cell 40, the polarization axis of the first polarization component PL1 emitted from the light source rotates four times at an angle of 90 degrees, diffuses once in the X-axis direction, and diffuses once in the Y-axis direction.

[0153] On the other hand, the polarization axis of the second polarization component PL2 incident on the first liquid crystal cell 10 is parallel to the long axis of the liquid crystal molecules on the first substrate S11 side of the first liquid crystal layer LC1. However, since the first electrode E11 does not generate a lateral electric field, the second polarization component PL2 proceeds to the second substrate S12 side without diffusion. Furthermore, the second polarization component PL2 rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it moves from the first substrate S11 side to the second substrate S12 side in the first liquid crystal layer LC1. Thus, the second polarization component PL2 transforms into the first polarization component PL1. The polarization axis of the first polarization component PL1 is parallel to the long axis of the liquid crystal molecules on the second substrate S12 side. The refractive index distribution of the liquid crystal molecules on the second substrate S12 side changes due to the electric field generated by the second electrode E12. Therefore, the first polarization component PL1, transformed from the first liquid crystal layer LC1, diffuses in the Y-axis direction due to the refractive index distribution formed by the liquid crystal molecules on the second substrate S12 side. That is, the second polarization component PL2 incident on the first liquid crystal cell 10 is transformed into the first polarization component PL1 during the process of passing through the first liquid crystal cell 10 and diffuses in the Y direction (diffuse light 1Y).

[0154] Then, the first polarization component PL1 (diffuse light 1Y) emitted from the first liquid crystal cell 10 is incident on the second liquid crystal cell 20. The polarization axis of the first polarization component PL1 (diffuse light 1Y) incident on the second liquid crystal cell 20 is in a direction that intersects (orthogonal to) the long axis direction of the liquid crystal molecules on the first substrate S21 side of the second liquid crystal layer LC2. However, since the first electrode E21 does not generate a lateral electric field, the first polarization component PL1 (diffuse light 1Y) travels to the second substrate S22 side without diffusion. In addition, the first polarization component PL1 (diffuse light 1Y) rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it travels from the first substrate S21 side to the second substrate S22 side in the second liquid crystal layer LC2. As a result, the first polarization component PL1 (diffuse light 1Y) transforms into the second polarization component PL2 (diffuse light 1Y). The polarization axis of the second polarization component PL2 is in a direction that intersects the long axis direction of the liquid crystal molecules on the second substrate S22 side. Therefore, although the refractive index distribution of the liquid crystal molecules on the second substrate S22 side changes due to the electric field generated by the second electrode E22, the second polarization component PL2 (diffuse light 1Y) is transmitted unaffected. That is, the first polarization component PL1 (diffuse light 1Y) incident on the second liquid crystal cell 20 is transformed into the second polarization component PL2 (diffuse light 1Y) during its passage through the second liquid crystal cell 20, but is transmitted without diffusion.

[0155] Thus, the second polarization component PL2 in the incident light temporarily transforms into the first polarization component PL1 before being incident on the first liquid crystal cell 10 and emitted from the second liquid crystal cell 20, and then transforms back into the second polarization component PL2, and diffuses once in the Y-axis direction in the first liquid crystal cell 10.

[0156] A second polarization component PL2 (diffuse light 1Y), which has undergone 90-degree optical rotation in the first liquid crystal cell 10 and the second liquid crystal cell 20 respectively and diffused once in the Y-axis direction in the first liquid crystal cell 10, is incident on the third liquid crystal cell 30. The polarization direction of the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 is in a direction that intersects (orthogonal to) the long axis direction of the liquid crystal molecules on the first substrate S31 side of the third liquid crystal layer LC3. Since the first electrode E31 does not generate a lateral electric field, the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 does not diffuse, and rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it moves from the first substrate S31 side to the second substrate S32 side in the third liquid crystal layer LC3. Thus, the second polarization component PL2 (diffuse light 1Y) is transformed into the first polarization component PL1 (diffuse light 1Y). In addition, the polarization direction of the first polarization component PL1 (diffuse light 1Y) is in a direction that intersects the long axis direction of the liquid crystal molecules on the second substrate S32 side. Therefore, although the refractive index distribution of the liquid crystal molecules on the second substrate S32 side changes due to the electric field generated by the second electrode E32, the first polarization component PL1 (diffuse light 1Y) is transmitted unaffected. That is, the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 is transformed into the first polarization component PL1 (diffuse light 1Y) during its passage through the third liquid crystal cell 30, but is transmitted without diffusion.

[0157] When the first polarization component PL1 (diffuse light 1Y), which passes through the third liquid crystal cell 30, diffuses once in the Y direction, and rotates by 90 degrees in the first liquid crystal cell 10, the second liquid crystal cell 20, and the third liquid crystal cell 30 respectively, is incident on the fourth liquid crystal cell 40, the polarization direction of the first polarization component PL1 (diffuse light 1Y) becomes parallel to the long axis direction of the liquid crystal molecules on the first substrate S41 side of the fourth liquid crystal layer LC4. However, since the first electrode E41 does not generate a lateral electric field, the first polarization component PL1 (diffuse light 1Y) incident on the fourth liquid crystal cell 40 does not diffuse. Instead, it rotates by 90 degrees according to the twisted orientation of the liquid crystal molecules as it travels from the first substrate S41 side to the second substrate S42 side in the fourth liquid crystal layer LC4. Thus, the first polarization component PL1 (diffuse light 1Y) transforms again into the second polarization component PL2 (diffuse light 1Y). The polarization direction of this second polarization component PL2 (diffuse light 1Y) is parallel to the long axis direction of the liquid crystal molecules on the second substrate S42 side. Here, since the refractive index distribution of the liquid crystal molecules on the second substrate S42 side changes due to the lateral electric field generated by the second electrode E42, the second polarization component PL2 (diffuse light 1Y) is affected by the refractive index distribution of the liquid crystal molecules and diffuses in the X-axis direction, and is emitted from the fourth liquid crystal cell 40 as the second polarization component (diffuse light 1X1Y).

[0158] Thus, the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 is temporarily transformed into the first polarization component PL1 (diffuse light 1Y) before being emitted from the fourth liquid crystal cell 40, and then transforms back into the second polarization component PL2 (diffuse light 1Y). It diffuses once in the X-axis direction in the fourth liquid crystal cell 40 and is emitted as the second polarization component PL2 (diffuse light 1X1Y).

[0159] Therefore, during the period from the incident on the first liquid crystal cell 10 to the emission from the fourth liquid crystal cell 40, the polarization axis of the second polarization component PL2 emitted from the light source rotates four times at an angle of 90 degrees, diffuses once in the X-axis direction, and diffuses once in the Y-axis direction.

[0160] according to Figure 10 The operation of the liquid crystal light control element 102 involves the first polarization component PL1 of the light emitted from the light source 106 diffusing once in the X-axis direction and once in the Y-axis direction, and the second polarization component PL2 diffusing once in the X-axis direction and once in the Y-axis direction, thereby forming a quadrilateral light distribution pattern. Since both the first polarization component PL1 and the second polarization component PL2 diffuse in the X-axis and Y-axis directions after optical rotation by the liquid crystal layer, light loss during optical rotation can be reduced. In other words, by preventing the first polarization component PL1 and the second polarization component PL2 from diffusing before the initial optical rotation, optical rotation occurring in the diffused state during the process can be eliminated, and light loss during optical rotation can be reduced. Therefore, when controlling the light distribution pattern of the light source by the liquid crystal light control element 102, shape disorder of the light distribution pattern can be suppressed.

[0161] In addition, according to Figure 10 The liquid crystal light control element 102 shown in the diagram prevents color distortion by using electrodes disposed in different liquid crystal cells and arranged on the opposite side from the light incident side through the liquid crystal layer to diffuse a polarization component in the X-axis and Y-axis directions.

[0162] Figure 10 The operating mode of the liquid crystal light control element 102 shown is such that no lateral electric field is generated through the first electrode of each liquid crystal cell; therefore, through... Figure 9 and Figure 12 The liquid crystal light control element shown can also form a quadrilateral light distribution pattern. Figure 9 and Figure 12 This illustrates an example where the first electrode of each liquid crystal cell is formed by a flat electrode (full-surface electrode). Figure 9 and Figure 12 In this context, the orientation of the liquid crystal molecules in each liquid crystal cell, the configuration of the second electrodes (E12, E22, E32, E42), and the control signals applied to the second electrodes are... Figure 10 The examples shown are the same (see reference). Figure 12).

[0163] such as insert Figure 12 As shown in the table, the transitions of the first polarization component PL1 and the second polarization component PL2 through the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30, and the fourth liquid crystal cell 40 are related to... Figure 10 The implementation methods shown are the same, so detailed descriptions are omitted. Figure 12 As shown, even if the first electrode is replaced with a flat electrode (full-surface electrode), the first polarization component PL1 of the light emitted from the light source (106) can be diffused once in the X-axis direction and once in the Y-axis direction, and the second polarization component PL2 can be diffused once in the X-axis direction and once in the Y-axis direction, thus forming a quadrilateral light distribution pattern.

[0164] Second implementation method:

[0165] This embodiment shows an example of the configuration and operation of a liquid crystal light control element 102 capable of distributing light emitted from a light source in a cross shape. Figure 13 This diagram illustrates the arrangement of strip electrodes in each liquid crystal cell of the liquid crystal light control element 102 according to this embodiment, and how the polarization state and diffusion pattern of incident light are controlled by each liquid crystal cell. Figure 13 The arrangement of the strip electrodes in the first liquid crystal unit 10, the second liquid crystal unit 20, the third liquid crystal unit 30 and the fourth liquid crystal unit 40 shown is the same as in the first embodiment.

[0166] Table 2 shows that... Figure 13 The control signals applied to each liquid crystal cell in the liquid crystal light control element 102 shown are illustrated. It should be noted that the control signals A, B, and E shown in Table 2 are... Figure 11 The control signals shown correspond to those shown.

[0167] [Table 2]

[0168]

[0169] like Figure 13As shown in Table 2, control signals are input to each liquid crystal cell of the liquid crystal light control element 102. Control signal E is input to the first strip electrode E11A and the second strip electrode E11B of the first liquid crystal cell 10, control signal A is input to the third strip electrode E12A, and control signal B is input to the fourth strip electrode E12B. As shown in Table 2, the third liquid crystal cell 30 is also input with control signals in the same way as the first liquid crystal cell 10. However, the orientation of the long side of the strip electrode, the orientation direction of the alignment film, and the orientation of the long axis of the liquid crystal molecules in the third liquid crystal cell 30 are different from those in the first liquid crystal cell 10. Control signal A is input to the first strip electrode E21A of the second liquid crystal cell 20, control signal B is input to the second strip electrode E21B, and control signal E is input to the third strip electrode E22A and the fourth strip electrode E22B. As shown in Table 2, the fourth liquid crystal cell 40 is also input with control signals in the same way as the second liquid crystal cell 20. However, the orientation of the long side of the strip electrode, the orientation of the alignment film, and the orientation of the long axis of the liquid crystal molecules in the fourth liquid crystal unit 40 are different from those in the first liquid crystal unit 10. Thus, Figure 13 The liquid crystal light control element 102 shown has a configuration that generates a lateral electric field on the side of the second substrate S12 and S32 in the first liquid crystal cell 10 and the third liquid crystal cell 30, and generates a lateral electric field on the side of the first substrate S21 and S41 in the second liquid crystal cell 20 and the fourth liquid crystal cell 40.

[0170] When the liquid crystal light control element 102 is activated, the control signals shown in Table 2 are input to each strip electrode of each liquid crystal cell. If the control signals shown in Table 2 are input to each liquid crystal cell, a lateral electric field is generated on the second substrate S12 and S32 side in the first liquid crystal cell 10 and the third liquid crystal cell 30, and a lateral electric field is generated on the first substrate S21 and S41 side in the second liquid crystal cell 20 and the fourth liquid crystal cell 40. The liquid crystal molecules are affected by the lateral electric field and their orientation state changes.

[0171] If in Figure 13 Focusing on the first polarization component PL1, the first polarization component PL1 is transformed into the second polarization component PL2 during the process of passing through the first liquid crystal cell 10, just like in the first embodiment, and is emitted from the second substrate S12 side without diffusion.

[0172] Then, the second polarization component PL2 emitted from the first liquid crystal cell 10 is incident on the second liquid crystal cell 20. The polarization axis of the second polarization component PL2 is parallel to the long axis of the liquid crystal molecules on the first substrate S21 side of the second liquid crystal layer LC2. Since the refractive index distribution of the liquid crystal molecules on the first substrate S21 side changes due to the lateral electric field generated by the first electrode E21, the second polarization component PL2 diffuses in the X-axis direction. In addition, the second polarization component PL2 rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it moves from the first substrate S21 side to the second substrate S22 side in the second liquid crystal layer LC2. As a result, the second polarization component PL2 (diffuse light 1X) diffused in the X-axis direction is transformed into the first polarization component PL1. Since the second electrode E22 does not generate a lateral electric field, the first polarization component PL1 (diffuse light 1X) passes through the second substrate S22 without diffusion and is emitted from the second liquid crystal cell 20. That is, the second polarization component PL2 incident on the second liquid crystal cell 20 diffuses in the X-axis direction as it passes through the second liquid crystal cell 20, transforms into the first polarization component PL1 (diffuse light 1X) and is emitted.

[0173] Thus, the first polarization component PL1 in the incident light temporarily transforms into the second polarization component PL2 before being incident on the first liquid crystal cell 10 and emitted from the second liquid crystal cell 20, and then transforms back into the first polarization component PL1, and diffuses once in the X-axis direction in the second liquid crystal cell 20.

[0174] Similar to the first embodiment, in the third liquid crystal cell 30, the long side direction of the first electrode E31 intersects the first electrode E11 of the first liquid crystal cell 10 and the first electrode E21 of the second liquid crystal cell 20 at a 90-degree angle, and the long side direction of the second electrode E32 intersects the second electrode E12 of the first liquid crystal cell 10 and the second electrode E22 of the second liquid crystal cell 20 at a 90-degree angle. Similarly, in the fourth liquid crystal cell 40, the long side direction of the first electrode E41 intersects the first electrode E11 of the first liquid crystal cell 10 and the first electrode E21 of the second liquid crystal cell 20 at a 90-degree angle, and the long side direction of the second electrode E42 intersects the second electrode E12 of the first liquid crystal cell 10 and the second electrode E22 of the second liquid crystal cell 20 at a 90-degree angle. Therefore, in the third and fourth liquid crystal cells, the phenomena generated in the first liquid crystal cell 10 and the second liquid crystal cell 20 for each polarization component are reversed. It should be noted that this intersection angle can be set within the range of 90 ± 10 degrees.

[0175] When the first polarization component PL1 (diffuse light 1X) passes through the second liquid crystal cell 20 and diffuses once in the X-axis direction, it is incident on the third liquid crystal cell 30. The polarization axis of the first polarization component PL1 (diffuse light 1X) is parallel to the long axis of the liquid crystal molecules on the first substrate S31 side of the third liquid crystal layer LC3. However, since the first electrode E31 does not generate a lateral electric field, the first polarization component PL1 (diffuse light 1X) incident on the third liquid crystal cell 30 does not diffuse. During its journey from the first substrate S31 side to the second substrate S32 side in the third liquid crystal layer LC3, it rotates 90 degrees according to the twisted orientation of the liquid crystal molecules. Thus, the first polarization component PL1 (diffuse light 1X) transforms into the second polarization component PL2 (diffuse light 1X). Here, the polarization axis of the second polarization component PL2 (diffuse light 1X) is parallel to the long axis of the liquid crystal molecules on the second substrate S32 side. Because the refractive index distribution of the liquid crystal molecules on the second substrate S32 side changes due to the lateral electric field generated by the second electrode E32, the second polarization component PL2 (diffuse light 1X) diffuses in the X-axis direction and is then emitted from the third liquid crystal cell 30. That is, the first polarization component PL1 (diffuse light 1X) incident on the third liquid crystal cell 30 is transformed into the second polarization component PL2 (diffuse light 1X) as it passes through the third liquid crystal cell 30 and further diffuses in the X-axis direction.

[0176] In the fourth liquid crystal cell 40, the first electrode E41 generates a lateral electric field, and the refractive index distribution of the liquid crystal molecules on the first substrate S41 side changes due to the lateral electric field generated by the first electrode E41. However, the polarization axis of the second polarization component PL2 (diffuse light 2X) incident on the fourth liquid crystal cell 40 is in a direction that intersects the long axis direction of the liquid crystal molecules on the first substrate S41 side of the fourth liquid crystal layer LC4, so it does not diffuse. In the fourth liquid crystal layer LC4, as it travels from the first substrate S41 side to the second substrate S42 side, it rotates 90 degrees according to the twisted orientation of the liquid crystal molecules. As a result, the second polarization component PL2 (diffuse light 2X) transforms into the first polarization component PL1 (diffuse light 2X). Since the second electrode E42 does not generate a lateral electric field, the first polarization component PL1 (diffuse light 2X) passes through the second substrate S42 without diffusion and is emitted from the fourth liquid crystal cell 40. That is, the second polarization component PL2 (diffuse light 2X) incident on the fourth liquid crystal cell 40 does not diffuse during its passage through the fourth liquid crystal cell 40, but is transformed into the first polarization component PL1 (diffuse light 2X) and emitted.

[0177] Thus, the first polarization component PL1 (diffuse light 1X) incident on the third liquid crystal cell 30 rotates by 90 degrees in the third liquid crystal layer LC3 and the fourth liquid crystal layer LC4 until it is emitted from the fourth liquid crystal cell 40, and diffuses in the X-axis direction in the third liquid crystal cell 30, and is emitted from the fourth liquid crystal cell 40 as the first polarization component PL1 (diffuse light 2X).

[0178] Therefore, during the period from the incident on the first liquid crystal cell 10 to the emission from the fourth liquid crystal cell 40, the polarization axis of the first polarization component PL1 emitted from the light source rotates four times at an angle of 90 degrees and diffuses twice in the X-axis direction.

[0179] Next, if in Figure 13 Focusing on the second polarization component PL2, the second polarization component PL2 is transformed into the first polarization component PL1 during the process of passing through the first liquid crystal cell 10, just like in the first embodiment. It diffuses in the Y-axis direction on the side of the second substrate S12 and is emitted from the side of the second substrate S12.

[0180] In the second liquid crystal cell 20, the first electrode E21 generates a lateral electric field, and the refractive index distribution of the liquid crystal molecules on the first substrate S21 side changes due to the lateral electric field generated by the first electrode E21. However, the polarization axis of the first polarization component PL1 (diffuse light 1Y) incident on the second liquid crystal cell 20 is in a direction that intersects (orthogonal to) the long axis direction of the liquid crystal molecules on the first substrate S21 side of the second liquid crystal layer LC2, so it does not diffuse. In the second liquid crystal layer LC2, it rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it travels from the first substrate S21 side to the second substrate S22 side. As a result, the first polarization component PL1 (diffuse light 1Y) transforms into the second polarization component PL2 (diffuse light 1Y). Since the second electrode E22 does not generate a lateral electric field, the second polarization component PL2 (diffuse light 1Y) passes through the second substrate S22 without diffusion and is emitted from the second liquid crystal cell 20. That is, the first polarization component PL1 (diffuse light 1Y) incident on the second liquid crystal cell 20 does not diffuse during the process of passing through the second liquid crystal cell 20, but is transformed into the second polarization component PL2 (diffuse light 1Y) and emitted.

[0181] Thus, the second polarization component PL2 in the incident light temporarily transforms into the first polarization component PL1 and diffuses once in the Y-axis direction until it is incident on the first liquid crystal cell 10 and emitted from the second liquid crystal cell 20. In the second liquid crystal cell 20, it transforms back into the second polarization component PL2 (diffuse light 1Y).

[0182] A second polarization component PL2 (diffuse light 1Y), which has undergone 90-degree optical rotation in the first liquid crystal cell 10 and the second liquid crystal cell 20 respectively and diffused once in the Y-axis direction in the first liquid crystal cell 10, is incident on the third liquid crystal cell 30. The polarization direction of the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 is in a direction that intersects (orthogonal to) the long axis direction of the liquid crystal molecules on the first substrate S31 side of the third liquid crystal layer LC3. Since the first electrode E31 does not generate a lateral electric field, the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 does not diffuse, and rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it moves from the first substrate S31 side to the second substrate S32 side in the third liquid crystal layer LC3. Thus, the second polarization component PL2 (diffuse light 1Y) is transformed into the first polarization component PL1 (diffuse light 1Y). In addition, the polarization direction of the first polarization component PL1 (diffuse light 1Y) is in a direction that intersects the long axis direction of the liquid crystal molecules on the second substrate S32 side. Therefore, although the refractive index distribution of the liquid crystal molecules on the second substrate S32 side changes due to the electric field generated by the second electrode E32, the first polarization component PL1 (diffuse light 1Y) is transmitted unaffected. That is, the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 is transformed into the first polarization component PL1 (diffuse light 1Y) during its passage through the third liquid crystal cell 30, but is transmitted without diffusion.

[0183] When the first polarization component PL1 (diffuse light 1Y), which diffuses once in the Y direction through the third liquid crystal cell 30 and undergoes a 90-degree optical rotation in the first liquid crystal cell 10, the second liquid crystal cell 20, and the third liquid crystal cell 30, is incident on the fourth liquid crystal cell 40, the polarization direction of the first polarization component PL1 (diffuse light 1Y) becomes parallel to the long axis direction of the liquid crystal molecules on the first substrate S41 side of the fourth liquid crystal layer LC4. Because the refractive index distribution of the liquid crystal molecules on the first substrate S41 side changes due to the lateral electric field generated by the first electrode E41, the first polarization component PL1 (diffuse light 1Y) diffuses in the Y-axis direction. Furthermore, the first polarization component PL1 (diffuse light 1Y) rotates 90 degrees according to the twisted orientation of the liquid crystal molecules as it travels from the first substrate S41 side to the second substrate S42 side in the fourth liquid crystal layer LC4. Thus, the first polarization component PL1 (diffuse light 2Y) diffused in the Y-axis direction transforms into the second polarization component PL2 (diffuse light 2Y) and is emitted from the fourth liquid crystal cell 40.

[0184] Thus, the second polarization component PL2 (diffuse light 1Y) incident on the third liquid crystal cell 30 is temporarily transformed into the first polarization component PL1 (diffuse light 1Y) before being emitted from the fourth liquid crystal cell 40. After that, it diffuses once in the Y-axis direction in the fourth liquid crystal cell 40 and is transformed into the second polarization component PL2 (diffuse light 2Y) before being emitted.

[0185] Therefore, during the period from the incident on the first liquid crystal cell 10 to the emission from the fourth liquid crystal cell 40, the polarization axis of the second polarization component PL2 emitted from the light source rotates four times at an angle of 90 degrees and diffuses twice in the Y-axis direction.

[0186] according to Figure 13 The liquid crystal light control element 102 shown diffuses the first polarization component PL1 of the light emitted from the light source 106 twice in the X-axis direction and the second polarization component PL2 twice in the Y-axis direction, thereby forming a cross-shaped light distribution pattern. The second polarization component PL2 diffuses in the Y-axis direction after optical rotation by the liquid crystal layer, thus reducing light loss during optical rotation. In other words, by preventing the second polarization component PL2 from diffusing before optical rotation, optical rotation occurring in the diffused state can be eliminated, reducing light loss during optical rotation. Therefore, when controlling the light distribution pattern of the light source by the liquid crystal light control element 102, shape disorder of the light distribution pattern can be suppressed.

[0187] In addition, according to Figure 13 The liquid crystal light control element 102 shown can prevent color distortion by using electrodes disposed in different liquid crystal cells and arranged on the opposite side of the light incident side through the liquid crystal layer to diffuse a polarization component in the X-axis or Y-axis direction.

[0188] Third implementation method:

[0189] This embodiment shows a third configuration example of the liquid crystal light control element 102. Figure 14 The arrangement of strip electrodes in each liquid crystal cell of the liquid crystal light control element 102 according to this embodiment is shown. Figure 14 The arrangement of the strip electrodes in the first liquid crystal cell 10, the second liquid crystal cell 20, the third liquid crystal cell 30 and the fourth liquid crystal cell 40 shown is the same as in the first embodiment, but the difference lies in the fact that the second liquid crystal layer LC2N of the second liquid crystal cell 20 and the fourth liquid crystal layer LC4N of the fourth liquid crystal cell 40 use negative liquid crystal.

[0190] By using negative liquid crystal in at least one of the multiple liquid crystal cells and positive liquid crystal in the others, the light distribution pattern of the light emitted from the light source can also be controlled. It should be noted that in this embodiment, the first electrode E11 of the first liquid crystal cell 10, the first electrode E21 of the second liquid crystal cell 20, the first electrode E31 of the third liquid crystal cell 30, and the first electrode E41 of the fourth liquid crystal cell 40 can be replaced with those in the first embodiment. Figure 12 The plate-shaped electrode shown is a full-surface electrode.

[0191] Fourth implementation method:

[0192] This embodiment shows a fourth configuration example of the liquid crystal light control element 102. Figure 15 The arrangement of strip electrodes in each liquid crystal cell of the liquid crystal light control element 102 according to this embodiment is shown. Figure 15 The arrangement of the strip electrodes in the first liquid crystal cell 10, second liquid crystal cell 20, third liquid crystal cell 30, and fourth liquid crystal cell 40 is the same as in the first embodiment, but the orientation direction of the alignment film (not shown) of the second liquid crystal cell 20 and the orientation direction of the alignment film (not shown) of the fourth liquid crystal cell 40 are different from those of the first liquid crystal cell 10 and the third liquid crystal cell 30. That is, the orientation direction of the alignment film (not shown) of the first liquid crystal cell 10 and the third liquid crystal cell 30 is a direction intersecting the long side direction of the strip electrode, while the orientation direction of the alignment film (not shown) of the second liquid crystal cell 20 and the fourth liquid crystal cell 40 is oriented in the same direction as the long side direction of the strip electrode. That is, as shown... Figure 15 As schematically shown, the long axes of the liquid crystal molecules in the liquid crystal layers of the first liquid crystal cell 10 and the third liquid crystal cell 30 are oriented in a direction intersecting the long side directions of the first electrodes E11, E31 and the second electrodes E12, E32. In contrast, the long axes of the liquid crystal molecules in the liquid crystal layers of the second liquid crystal cell 20 and the fourth liquid crystal cell 40 are oriented in a direction parallel to the long side directions of the first electrodes E21, E41 and the second electrodes E22, E42. This is different from the first embodiment.

[0193] according to Figure 15In the configuration shown, the alignment films (not shown) on the first substrate S11 and S41 sides of the first liquid crystal cell 10 and the fourth liquid crystal cell 40 are aligned in a direction parallel to the X-axis, and the alignment films (not shown) on the second substrate S12 and S42 sides are aligned in a direction parallel to the Y-axis. The long side of the strip pattern of the first electrode E11 of the first liquid crystal cell 10 is aligned in a direction parallel to the Y-axis, the long side of the strip pattern of the second electrode E12 is aligned in a direction parallel to the X-axis, the long side of the strip pattern of the first electrode E41 of the fourth liquid crystal cell 40 is aligned in a direction parallel to the X-axis, and the long side of the strip pattern of the second electrode E42 is aligned in a direction parallel to the Y-axis.

[0194] Furthermore, the alignment films (not shown) on the first substrates S21 and S31 sides of the second liquid crystal unit 20 and the third liquid crystal unit 30 are aligned in a direction parallel to the Y-axis, and the alignment films (not shown) on the second substrates S22 and S32 sides are aligned in a direction parallel to the X-axis. Moreover, the long side of the strip pattern of the first electrode E21 of the second liquid crystal unit 20 is aligned in a direction parallel to the Y-axis, the long side of the strip pattern of the second electrode E22 is aligned in a direction parallel to the X-axis, and the long side of the strip pattern of the first electrode E31 of the third liquid crystal unit 30 is aligned in a direction parallel to the X-axis, and the long side of the strip pattern of the second electrode E32 is aligned in a direction parallel to the Y-axis. It should be noted that in this embodiment, the alignment direction of the alignment film is set to a direction 90 degrees relative to the extending direction of the electrode with the strip pattern, according to the definitions of the X-axis and Y-axis directions, but it can also be set to a direction of 90 ± 10 degrees.

[0195] Table 3 shows that... Figure 15 This is an example of the control signals applied to each liquid crystal cell in the liquid crystal light control element 102 shown. It should be noted that the control signals A, B, and E shown in Table 3 are... Figure 11 The control signals shown correspond to these. Additionally, the orientation directions marked as intersecting or parallel in Table 3 correspond to the orientations of the liquid crystal molecules described above.

[0196] [Table 3]

[0197]

[0198] like Figure 15 As shown in Table 3, control signals are input to each liquid crystal cell of the liquid crystal light control element 102 in the same manner as in the first embodiment. When the liquid crystal light control element 102 is activated, the control signals shown in Table 3 are input to each strip electrode of each liquid crystal cell.

[0199] It should be noted that, in this embodiment, the first electrode E11 of the first liquid crystal unit 10, the first electrode E21 of the second liquid crystal unit 20, the first electrode E31 of the third liquid crystal unit 30, and the first electrode E41 of the fourth liquid crystal unit 40 can be replaced with those in the first embodiment. Figure 12 The plate-shaped electrode shown is a full-surface electrode.

[0200] Fifth implementation method:

[0201] In the liquid crystal light control element 102 shown in the first embodiment, only the first electrode E11 of the first liquid crystal cell 10 may be... Figure 9 A flat electrode (full-surface electrode) as shown. Figure 16 The diagram shows a configuration in which the first electrode E11 of the liquid crystal light control element 102 shown in the first embodiment is a planar electrode E11. With this electrode configuration, the same operation as the liquid crystal light control element 102 shown in the first embodiment can be performed. It should be noted that this configuration is not limited to this one; a configuration in which the electrode on the first substrate side of any one or more of the first to fourth liquid crystal cells is also a planar electrode can also be used.

[0202] Sixth implementation method:

[0203] This embodiment shows the orientation shape of the liquid crystal light control element shown in the first embodiment and the liquid crystal light control element shown in the second embodiment.

[0204] Figure 17A The alignment shape obtained by the liquid crystal light control element shown in the first embodiment is illustrated. For example... Figure 17A As shown, a square orientation shape can be obtained by using the liquid crystal light control element and its driving conditions as described in the first embodiment.

[0205] Figure 17B Reference Example 1 is shown. Reference Example 1 shows the result of driving a liquid crystal cell with the same electrode configuration as the liquid crystal light control element shown in the first embodiment, but under different driving conditions, where a voltage is applied to the first electrode side of each liquid crystal cell and no transverse electric field is generated on the second electrode side. For example... Figure 17B As shown, in the case of Reference Example 1, an orientation shape close to a square was also obtained, but... Figure 17A As can be seen from the comparison of the results shown, the contour has been deformed.

[0206] Figure 18A The alignment shape obtained by the liquid crystal light control element shown in the second embodiment is illustrated. For example... Figure 18A As shown, a cross-shaped orientation shape can be obtained by using the liquid crystal light control element and its driving conditions as described in the first embodiment.

[0207] Figure 18B Reference Example 2 is shown. Reference Example 2 illustrates a situation where the electrode configuration of the liquid crystal cells is opposite to that of the liquid crystal light control element shown in the second embodiment, and a lateral electric field is generated at the first electrode E11 of the first liquid crystal cell 10, the second electrode E22 of the second liquid crystal cell 20, the first electrode E31 of the third liquid crystal cell 30, and the second electrode E42 of the fourth liquid crystal cell 40. For example... Figure 18B As shown, in the case of Reference Example 1, an orientation shape close to a cross shape was also obtained, but with... Figure 18A The results show that the cross shape of the orientation shape shown in the second embodiment is sharper.

[0208] Depend on Figure 17A and Figure 17B , Figure 18A and Figure 18B The results clearly show that when a lateral electric field is generated only on one side of the electrode (the electrode on the first substrate side or the electrode on the second substrate side) in a liquid crystal cell, as shown in the first embodiment and the second embodiment, a sharper orientation shape can be obtained in the liquid crystal cell on the light source side by diffusion through the electrode on the opposite side of the light incident side (the second electrode of the second substrate).

[0209] That is, as described in this embodiment above, by preventing the light incident on the first liquid crystal element 10 from diffusing before optical rotation, optical rotation can be prevented in a diffused state, light loss during optical rotation can be reduced, and shape disorder of the light distribution pattern can be suppressed.

[0210] Explanation of reference numerals in the attached figures

[0211] 10: First liquid crystal unit, 20: Second liquid crystal unit, 30: Third liquid crystal unit, 40: Fourth liquid crystal unit, 100: Liquid crystal light control device, 102: Liquid crystal light control element, 104: Circuit board, 106: Light source unit, S11, S21, S31, S41: First substrate, S12, S22, S32, S42: Second substrate, F1: First flexible wiring substrate, F2: Second flexible wiring substrate, F3: Third flexible wiring substrate, F4: Fourth flexible wiring substrate, TA1: First transparent adhesive layer, TA2: Second transparent adhesive layer, TA3: Third transparent adhesive layer, LC1: First liquid crystal layer, LC2: Second liquid crystal layer, LC3: Third liquid crystal layer, LC4: Fourth liquid crystal layer, E11, E21, E31, E41: First electrode, E11A, E21A, E31A, E41A: First strip electrode, E11B E21B, E31B, E41B: Second strip electrode; E12, E22, E32, E42: Second electrode; E12A, E22A, E32A, E42A: Third strip electrode; E12B, E22B, E32B, E42B: Fourth strip electrode; PL11: First power supply line; PL12: Second power supply line; PL13: Third power supply line; PL14: Fourth power supply line; PL15: Fifth power supply line; PL16: Sixth power supply line; T11: First connecting terminal; T12: Second connecting terminal; T13: Third connecting terminal; T14: Fourth connecting terminal; PT11: First power supply terminal; PT12: Second power supply terminal; PT13: Third power supply terminal; PT14: Fourth power supply terminal; AL11: First alignment film; AL12: Second alignment film; SE: Sealing material; CP11: First conductive component.

Claims

1. A liquid crystal light control device, characterized in that, include: A first liquid crystal cell is provided. Light including a first polarization component and a second polarization component is incident on the first liquid crystal cell. The first polarization component has a polarization axis in the Y-axis direction, and the second polarization component has a polarization axis in the X-axis direction that intersects the polarization axis of the first polarization component. The second liquid crystal unit overlaps with the first liquid crystal unit; The third liquid crystal unit overlaps with the second liquid crystal unit; as well as The fourth liquid crystal unit overlaps with the third liquid crystal unit. The first liquid crystal unit, the second liquid crystal unit, the third liquid crystal unit, and the fourth liquid crystal unit each include: A first substrate having a first alignment film; The second substrate has electrodes comprising a strip-shaped pattern and a second alignment film; and The liquid crystal layer between the first substrate and the second substrate The orientation direction of the first orientation film is set to intersect with the orientation direction of the second orientation film. The long side of the strip pattern in the electrode is arranged in a direction intersecting the orientation direction of the second alignment film, and the electrode containing the strip pattern generates a transverse electric field in the same direction as the orientation direction of the second alignment film. The electrode comprising the strip pattern includes: At least one first strip electrode having the strip pattern; and At least one second strip electrode having the strip pattern, The at least one first strip electrode and the at least one second strip electrode are spaced apart and alternately arranged. The first strip electrode and the second strip electrode are arranged with a center-to-center distance equal to the sum of the width of the first strip electrode and the interval between the ends of the first and second strip electrodes. The first substrate and the second substrate are arranged opposite each other at intervals. The interval has a size greater than or equal to the inter-center distance. The orientation direction of the first alignment film of the first liquid crystal cell is parallel to the orientation direction of the first alignment film of the second liquid crystal cell, and the orientation directions of the first alignment film of the third liquid crystal cell and the first alignment film of the fourth liquid crystal cell are parallel. The orientation directions of the first alignment film of the first liquid crystal cell and the second alignment film of the second liquid crystal cell, and the orientation directions of the first alignment film of the third liquid crystal cell and the second alignment film of the fourth liquid crystal cell, are arranged in an intersecting manner. When a lateral electric field is generated only on one side of the second substrate by inputting control signals to the first liquid crystal cell, the second liquid crystal cell, the third liquid crystal cell, and the fourth liquid crystal cell, respectively. During the period from the time the first polarization component is incident on the first liquid crystal cell to the time it is emitted from the fourth liquid crystal cell, its polarization axis rotates four times at an angle of 90 degrees, diffuses once in the X-axis direction, and diffuses once in the Y-axis direction. During the period from the second polarization component being incident on the first liquid crystal cell to being emitted from the fourth liquid crystal cell, the polarization axis rotates four times at an angle of 90 degrees, diffuses once in the X-axis direction, and diffuses once in the Y-axis direction.

2. The liquid crystal light control device according to claim 1, wherein, In both the first and second liquid crystal cells, the long side of the strip-shaped pattern of the electrode containing the strip-shaped pattern is arranged in the X-axis direction. The long side of the strip pattern of the electrode in each of the third and fourth liquid crystal cells is arranged in the Y-axis direction, which intersects the X-axis direction. The X-axis direction intersects the orientation direction of the first orientation film, and the Y-axis direction intersects the orientation direction of the second orientation film.

3. The liquid crystal light control device according to claim 1, wherein, A transverse electric field is generated between the first strip electrode and the second strip electrode.

4. The liquid crystal light control device according to claim 1, wherein, The liquid crystal layer is a twisted nematic liquid crystal.

5. The liquid crystal light control device according to claim 1, wherein, The first substrate has a flat electrode.

6. A liquid crystal light control device, characterized in that, include: A first liquid crystal cell is provided. Light including a first polarization component and a second polarization component is incident on the first liquid crystal cell. The first polarization component has a polarization axis in the Y-axis direction, and the second polarization component has a polarization axis in the X-axis direction that intersects the polarization axis of the first polarization component. The second liquid crystal unit overlaps with the first liquid crystal unit; The third liquid crystal unit overlaps with the second liquid crystal unit; as well as The fourth liquid crystal unit overlaps with the third liquid crystal unit. The first liquid crystal unit, the second liquid crystal unit, the third liquid crystal unit, and the fourth liquid crystal unit each include: A first substrate having a first electrode comprising a strip-shaped pattern and a first alignment film; The second substrate has a second electrode comprising a strip-shaped pattern and a second alignment film; and The liquid crystal layer between the first substrate and the second substrate The orientation direction of the first alignment film intersects with the orientation direction of the second alignment film, and the long side direction of the strip pattern of the first electrode intersects with the long side direction of the strip pattern of the second electrode. The long side of the strip pattern of the second electrode is arranged in a direction that intersects the orientation direction of the second alignment film. In the first liquid crystal cell and the third liquid crystal cell, the second electrode generates a lateral electric field in the same direction as the orientation direction of the second alignment film. In the second and fourth liquid crystal cells, the first electrode generates a lateral electric field in the same direction as the orientation direction of the first alignment film. The first electrode includes: At least one first strip electrode having the strip pattern; and At least one second strip electrode having the strip pattern, The at least one first strip electrode and the at least one second strip electrode are spaced apart and alternately arranged. The first strip electrode and the second strip electrode are arranged with a center-to-center distance equal to the sum of the width of the first strip electrode and the interval between the ends of the first and second strip electrodes. The first substrate and the second substrate are arranged opposite each other at intervals. The interval has a size greater than or equal to the inter-center distance. The orientation direction of the first alignment film of the first liquid crystal cell is parallel to the orientation direction of the first alignment film of the second liquid crystal cell, and the orientation directions of the first alignment film of the third liquid crystal cell and the first alignment film of the fourth liquid crystal cell are parallel. The orientation directions of the first alignment film of the first liquid crystal cell and the second alignment film of the second liquid crystal cell, and the orientation directions of the first alignment film of the third liquid crystal cell and the second alignment film of the fourth liquid crystal cell, are arranged in an intersecting manner. When a lateral electric field is generated on one side of the second substrate in the first liquid crystal cell and the third liquid crystal cell, and a lateral electric field is generated on one side of the first substrate in the second liquid crystal cell and the fourth liquid crystal cell, by inputting control signals to each of the first liquid crystal cell, the second liquid crystal cell, the third liquid crystal cell, and the fourth liquid crystal cell, respectively, a lateral electric field is generated on one side of the first substrate in the second liquid crystal cell and the fourth liquid crystal cell. During the period from the time the first polarizing component is incident on the first liquid crystal cell to the time it is emitted from the fourth liquid crystal cell, its polarization axis rotates four times at an angle of 90 degrees and diffuses twice in the X-axis direction. During the period from the second polarization component being incident on the first liquid crystal cell to being emitted from the fourth liquid crystal cell, the polarization axis rotates four times at an angle of 90 degrees and diffuses twice in the Y-axis direction.

7. The liquid crystal light control device according to claim 6, wherein, The orientation direction of the second alignment film of the first liquid crystal cell intersects with the orientation direction of the second alignment film of the third liquid crystal cell. The orientation direction of the first alignment film of the second liquid crystal cell intersects with the orientation direction of the first alignment film of the fourth liquid crystal cell.

8. The liquid crystal light control device according to claim 6 or 7, wherein, The second electrode includes: At least one third strip electrode having the strip pattern; and At least one fourth strip electrode having the strip pattern, The at least one third strip electrode and the at least one fourth strip electrode are spaced apart and arranged alternately.

9. The liquid crystal light control device according to claim 6, wherein, The liquid crystal layer is a twisted nematic liquid crystal.

Images