KR20150101309A - Liquid optical device system and method for driving liquid optical device - Google Patents

Abstract

A liquid optical element system and a driving method thereof are disclosed. According to the disclosed driving method, a voltage is applied to a liquid optical element including a nonpolar liquid and a polarizable liquid disposed in a space surrounded by a partition, first and second electrodes disposed on mutually opposing side walls of the partition, In the operation of changing the angle of contact of the polarized liquid, the driving voltage of the two-stage structure of the first voltage and the second voltage applied for a predetermined period of time is applied and driven. At this time, the second voltage may be an excessive driving voltage as compared to the first voltage.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid optical device,

And more particularly, to a liquid optical element system and a liquid-optical element driving method for driving a liquid-optical element so as to be capable of providing a multi-viewpoint three-dimensional image.

2. Description of the Related Art In recent years, there has been a great demand for a three-dimensional image display device that provides stereoscopic images in various fields such as games, advertisements, medical images, education, and military. In addition, as high-resolution televisions become popular, a three-dimensional television capable of viewing television in three dimensions is gradually being commercialized. Accordingly, various 3D image display technologies have been proposed. The three-dimensional image display device which is currently being commercialized uses binocular parallax of the two eyes. By providing the left eye image and the right eye image having different viewpoints to the left and right eyes of viewers, the viewer can feel the three- . Such a three-dimensional image display device includes a spectacular three-dimensional image display device requiring special glasses and a non-eye-tight three-dimensional image display device that does not require glasses.

However, since the existing three-dimensional image display device which provides only two viewpoints of the left eye image and the right eye image does not reflect the change of viewpoint according to the movement of the viewer, there is a limit to providing a natural three-dimensional feeling. Therefore, a re-pointing three-dimensional image display device capable of providing a plurality of viewpoints in order to provide a natural motion parallax has been proposed. The re-pointing three-dimensional image display device is a device for providing three-dimensional images at different viewpoints in a plurality of viewing zones.

In recent years, efforts have been made to apply liquid optical elements as active elements to a three-dimensional (3D) image display apparatus. Liquid optical elements, such as liquid prism elements, use electrowetting techniques.

Electrodewetting is a technique in which a hydrophobic insulator is coated on an electrode, a polarized fluid and a nonpolar fluid are brought into contact with the electrode, and a voltage is applied to control the surface tension of the polarized fluid to change the contact angle of the polarized fluid and the shape of the interface Change. When a voltage is applied to a polarized fluid, the property of the hydrophobic interface of the polarized fluid changes to be hydrophilic and the contact angle of the polarized fluid decreases, so that the polarized fluid pushes away the non-polar fluid, A liquid prism element can be obtained.

In the liquid prism element using the electrowetting, the contact angle of the polarized fluid changes according to the applied voltage, and the slope of the interface, that is, the prism angle can be changed. Since the refraction angle of the transmitted light changes according to the change in the prism angle, the prism angle drive can transmit light to a desired point in time.

A liquid optical element system and a liquid optical element driving method capable of adjusting the refraction angle of light at a sufficient reaction speed to enable realization of a reentrant three-dimensional image display device are provided.

A liquid-optical element driving method according to an embodiment of the present invention is a method of driving a liquid-optical element including a non-polar liquid and a polar liquid disposed in a space surrounded by a partition wall, In order to drive the device so as to change the contact angle of the polarized liquid by applying a voltage to the device, a drive voltage of a two-step structure of a first voltage and a second voltage for a predetermined period of time, And then drives it. At this time, the second voltage may be an excessive driving voltage as compared with the first voltage.

Here, the second voltage may be 1.2 times larger than the first voltage.

The second voltage may be 1.5 times larger than the first voltage.

The second voltage may be 1.2 to 2 times larger than the first voltage.

The second voltage may be applied for 0.1 to 3 ms.

The second voltage may be set within a range in which the contact angle stabilization time is less than or equal to 2 ms in the contact angle changing operation of the polarized liquid.

The driving voltage may be applied at a fixed frequency.

The first voltage of the driving voltage may be a predetermined voltage.

Setting the second voltage to be greater than the first voltage; And applying a driving voltage having a two-step structure of the first voltage and the second voltage applied thereto to change a contact angle of the polarized liquid.

The second voltage may be applied for 0.1 to 3 ms.

The second voltage may be set within a range in which the contact angle stabilization time is less than or equal to 2 ms in the contact angle changing operation of the polarized liquid.

A liquid-optical element system according to an embodiment of the present invention includes a nonpolar liquid and a polarizable liquid disposed in a space surrounded by a partition wall, first and second electrodes disposed on mutually opposing side walls of the partition, A liquid optical element in which a contact angle of the polarized liquid changes according to a voltage; Applying a voltage to the liquid-optical element and applying a driving voltage having a two-step structure of a first voltage and a second voltage applied for a predetermined period of time and an excessive driving voltage relative to the first voltage, And a driving unit for driving the driving unit to change the driving voltage.

The first voltage may be a predetermined voltage.

The second voltage may be 1.2 times larger than the first voltage.

The second voltage may be 1.5 times larger than the first voltage.

The second voltage may be 1.2 to 2 times larger than the first voltage.

The second voltage may be applied for 0.1 to 3 ms.

The second voltage may be set within a range in which the contact angle stabilization time is less than or equal to 2 ms in the contact angle changing operation of the polarized liquid.

The driving voltage may be applied at a fixed frequency.

A three-dimensional image display apparatus according to an embodiment of the present invention includes: an image generating unit for generating an image; The liquid optical element system described above adapted to change the path of light from the image generation unit; And a 3D optical part provided between the image generating part and the liquid-optical element of the liquid-optical element system for separating the viewpoint.

According to the driving method of the liquid-optical element system according to the embodiment of the present invention, by using the driving voltage having the two-stage structure in which the second voltage, which is the transient voltage, is applied for a predetermined time and then the first voltage is applied, It is possible to adjust the angle of refraction of the light at a sufficiently fast reaction speed and transmit the light to a desired point of time, thereby realizing a re-pointing three-dimensional image display device.

1 schematically shows a liquid optical element system including a liquid prism element as an example of a liquid optical element.
2 is a conceptual diagram schematically showing an example of the structure of a multi-viewpoint three-dimensional image display device including a liquid optical element.
3A to 3C are conceptual diagrams illustrating the operation of one prism cell of the liquid optical element of the multi-viewpoint three-dimensional image display apparatus of FIG.
4 shows an example of driving voltage waveforms applied to the liquid-optical element driving method according to the embodiment of the present invention.
FIG. 5 shows a gradient of the interface between the polarizing liquid and the non-polar liquid in the liquid optical element according to the driving voltage application step when the driving voltage is applied according to the liquid-optical element driving method according to the embodiment of the present invention.
6A shows a driving voltage of a simple rectangular waveform as a comparative example.
6B shows the slope change of the interface between the polarizable liquid and the non-polar liquid over time when a driving voltage of a simple rectangular waveform is applied to the liquid optical element.
FIG. 7 is a graph showing the relationship between the first voltage V2 and the second voltage V3 by applying a driving voltage having a two-stage structure of 1.5 times, 1.7 times, and 2.0 times the transient voltage of the first voltage V2, FIG. 5 is a graph showing a change in a settling time according to a transient voltage application time T when the liquid optical element is driven according to an embodiment of the present invention. FIG.
8 shows a time lapse when using a driving voltage to which a transient voltage is not applied and a driving voltage to which a transient voltage 1.5 times larger than the first voltage V2, i.e., a driving voltage to which the second voltage V3 is applied for 1.9 ms, Of the polar liquid and nonpolar liquid.

Hereinafter, a liquid-optical element system and a liquid-optical element driving method according to embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same elements, and the sizes and thicknesses of the respective elements in the drawings may be exaggerated for clarity and convenience of explanation. Also, what is referred to below as "upper" or "upper" may include not only being directly on, but also being noncontact.

Hereinafter, a liquid-optical element system and a liquid-optical element driving method according to an embodiment of the present invention will be described as an example of a liquid-prism element and a multi-viewpoint three-dimensional image display device using the liquid- The embodiments of the present invention are not limited thereto and can be applied to various optical devices in which active light refraction direction adjustment is required at a sufficiently high reaction speed.

1 schematically shows a liquid-optical element system 50 including a liquid prism element as an example of a liquid-optical element. 1 shows the structure of one prism cell 10 of a liquid prism element. When a liquid optical element system 50 including a two-dimensional array of prism cells 10 is employed in a three-dimensional image display apparatus, As can be seen from the following description, the direction of refraction of the light can be actively changed, which makes it possible to implement a multi-view 3D image display device.

1, a liquid-optical element system 50 according to an embodiment of the present invention includes a liquid-optical element 40 and a driving unit 15 for driving the liquid-optical element 40. The liquid-

The liquid optical element 40 includes a non-polar liquid and a polar liquid disposed in a space surrounded by the partition, first and second electrodes disposed on mutually opposing side walls of the partition, The contact angle of the polar liquid may be changed. The driving unit 15 applies a voltage to the liquid optical element 40 and generates a driving voltage having a two-stage structure of a first voltage and a second voltage which is applied for a predetermined period of time and is an excessive driving voltage with respect to the first voltage So that the contact angle of the polarized liquid can be changed.

The liquid-optical element 40 may include, for example, a liquid prism element including a two-dimensional array of the prism cells 10 as illustrated in FIG. At this time, the prism cell 10 includes upper and lower transparent substrates 1 and 6 arranged opposite to each other, vertical barrier ribs 2 formed on the lower transparent substrate 1, and barrier ribs 2 formed on both side walls of the vertical barrier rib 2 A dielectric film 4 formed to completely cover the first and second electrodes 3a and 3b and the first and second electrodes 3a and 3b disposed to face each other; A common electrode 7 disposed on the lower surface of the upper transparent substrate 6 and a nonpolar liquid 8 and a polarizable liquid 9 disposed in the space surrounded by the vertical partition 2, . ≪ / RTI >

Although the two vertical partition walls 2 are shown in FIG. 1, the vertical partition 2 may be a single structure formed in the form of a mesh so that a plurality of small spaces are formed therein. The first and second electrodes 3a and 3b may be disposed on both side walls of one vertical partition 2, respectively. As shown in FIG. 1, the first electrode 3a and the second electrode 3b may be arranged to face each other with a space formed by the vertical partition 2 interposed therebetween.

The dielectric film 4 formed to cover the first and second electrodes 3a and 3b functions to electrically isolate the first and second electrodes 3a and 3b and the liquid 8 and 9 in the space. The dielectric film 4 may be formed to completely cover the first and second electrodes 3a and 3b. The hydrophobic film 5 formed along the surface of the dielectric film 4 is formed so that the polarized liquid 9 such as water easily forms a predetermined contact angle at the interface 12 with the nonpolar liquid 8 such as oil can do. The hydrophobic coating 5 may also be formed to completely cover the dielectric film 4.

The nonpolar liquid 8 and the polarizable liquid 9 disposed in the space defined by the vertical partition 2 have a high transmittance so that light can pass through with little loss and light can be refracted at their interface 12 To have different refractive indexes. 1, the density of the nonpolar liquid 8 may be higher than the density of the polarizable liquid 9 so that the nonpolar liquid 8 is disposed downward in the space. The materials of the nonpolar liquid 8 and the polarizable liquid 9 satisfying these conditions are very diverse. For example, the polarizable liquid 9 may include, for example, about 0.0085 wt% of polyacrylic acid (PAA) Electrolyte solution can be used. DI water including about 0.005M NaCl and about 0.1 wt% sodium dodecyl sulfate (SDS) can be used as the polar liquid 9. As the nonpolar liquid 8, for example, bromonaphthalene or chloronaphthalene may be used.

The non-polar liquid 8 on the lower side in the space defined by the vertical partition 2 can be disposed separately for each prism cell 10, for example. The polarized liquid 9 disposed above the space can be arranged to extend, for example, over the entire prism cells 10 in the liquid prism element. To this end, there may be a predetermined gap between the lower surface of the upper transparent substrate 6 and the upper surface of the vertical partition 2.

In the prism cell 10 having the above-described structure, when the voltages applied to the two electrodes 3a and 3b are adjusted, the contact angle of the polarized liquid 9 is changed, The contact angle alpha between the interface 12 of the liquid 8 and the vertical partition wall 2 can be adjusted. Therefore, by appropriately adjusting the voltages applied to the electrodes 3a and 3b, the interface 12 between the polarized liquid 9 and the nonpolar liquid 8 can be perpendicular to the optical axis OX or perpendicular to the optical axis OX Can be inclined. For example, a predetermined voltage is applied to the first electrode 3a so that the interface 12 forms a contact angle beta of, for example, 120 DEG on the left side of the vertical partition 2, A predetermined voltage can be applied to the second electrode 3b so that the interface 12 forms a contact angle alpha of, for example, 60 degrees. The interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 can then be inclined at an angle of about 60 with respect to the optical axis OX.

Therefore, when the voltages applied to the electrodes 3a and 3b are appropriately adjusted to adjust the inclination of the interface 12 between the polarized liquid 9 and the nonpolar liquid 8, the prism angle is adjusted, 10, the incident light can be refracted at a desired angle to change the traveling direction of the incident light.

In this way, when the liquid-optical element 40 is provided so as to include the array of the prism cells 10, the driving unit 15 is provided between the first and second Are electrically connected to the electrodes 3a and 3b and the common electrode 7 disposed on the lower surface of the upper transparent substrate 6, respectively. The driving unit 15 applies a driving voltage to the first and second electrodes 3a and 3b to drive the contact angle of the polarized liquid 9 disposed in the space of the prism cell 10 to change. Whereby the contact angle between the interface 12 of the polarizable liquid 9 and the nonpolar liquid 8 and the vertical partition wall 92 can be adjusted.

4 and 5, the driving unit 15 applies a first voltage V2 and a second voltage V2 for a predetermined time T prior to the first voltage V2, And the second voltage (V3) is applied to the polarizing liquid (9) so that the contact angle of the polarized liquid (9) is changed, so that the reaction time of the liquid optical element (40) can be greatly reduced. The structure of the driving section 15 of the liquid-optical element system 50 according to another embodiment is not limited to the two-stage structure including the application period of the first voltage V2 and the application period of the second voltage V3. The driving voltage can be applied in two or more stages. For example, on the time axis, the driving unit 15 may apply a driving voltage so as to have a plurality of voltage intervals having different multi-step sizes. The magnitude of the voltage in at least one of the plurality of voltage intervals may have an excessive magnitude in comparison with the magnitude of the other voltages.

2 is a conceptual view schematically showing an example of the structure of a multi-viewpoint three-dimensional image display device including a liquid-optical element system 50 according to an embodiment of the present invention.

2, the three-dimensional display device 100 includes an image generating unit 20 for generating an image, and the liquid optical element system 50 (not shown) provided to convert the path of light from the image generating unit 20 ). The three-dimensional display device 100 may further optionally include a 3D optic portion 30 that separates the viewpoint between the image generating portion 20 and the liquid-optic element 40 of the liquid- have.

The image generating unit 20 may include a light source 21 and a display panel 22 that forms an image using light from the light source 21. [ For example, the display panel 22 may include a liquid crystal display (LCD), a digital micromirror device (DMD), a liquid crystal on silicon (LCOS), or a spatial light modulator (SLM). 2, the image generating unit 20 is shown as including a separate light source 21, but this is only one example, and the present embodiment is not limited thereto. For example, the image generating unit 20 may include a self-luminous display panel such as an organic light emitting diode (OLED) or a plasma display panel (PDP), which does not require a separate light source.

The liquid-optical element system 50 may include a liquid-optical element 40 and a driving unit 15, as described above with reference to Fig. The liquid optical element 40 can change the traveling path of the light traveling from the image generating unit 20 by changing the contact angle of the polarized liquid 9 in accordance with the driving of the driving unit 15. [

The liquid-optical element 40 changes the path of light to make the viewpoint of the image into multi-view points P1 to P6. For example, the liquid optical element 40 may be a liquid prism element, which may be an array of the prism cells 10 described above, and electrically adjusts an angle at which the light is refracted to provide a plurality of viewpoint images in a time- can do.

3A, when the interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 is not tilted in the prism cell 10, the light L changes in the path of the path Without passing through the prism cell 10. 3B, when the prism cell 10 is electrically controlled to tilt the interface 12 to the first angle, the light is guided by the interface 12 at an angle (+? 1) relative to the optical axis OX And passes through the prism cell 10. Conversely, as shown in FIG. 3C, when the prism cell 10 is electrically controlled to tilt the interface 12 to the second angle, light is guided to the (-) axis by the interface 12 with respect to the optical axis OX, 2 &thetas; 2), and passes through the prism cell 10. [

The image generating unit 20 may generate images at different time points in time and a plurality of prism cells 10 in the liquid optical element 40 may be generated by the driving unit 15 in the image generating unit 20, And may be driven to refract light including images of different viewpoints at different angles. For example, when the image of the first viewpoint is output from the image generator 20, the prism cell 10 may be driven to be in a non-tilted state as shown in FIG. 3A. When the second viewpoint image is outputted from the image generator 20, the prism cell 10 may be inclined at a first angle as shown in FIG. 3B. When the image generator 20 outputs the third viewpoint image, the prism cell 10 may be inclined at a second angle as shown in FIG. 3C. More images can be displayed according to the driving speed of the prism cell 10 and the slope of the interface 12.

In this case, the first voltage V2 is applied by the driving unit 15 and the second voltage V3, which is a driving voltage which is applied for a predetermined period of time T and is excessively higher than the first voltage V2, Since the contact angle of the polarized liquid 9 is changed by applying the driving voltage, the reaction time of the liquid optical element 40 is greatly reduced, and the number of viewpoints can be greatly increased.

The 3D optical unit 30 may be an optical element capable of separating the field of view, such as a lenticular lens array, a microlens array, or a parallax barrier. The 3D optical unit 30 may focus the images output from the image generating unit 20 separately in a plurality of viewports. The technique of separating the viewing area by the 3D optical unit 30 is well known in the art, and thus a detailed description thereof will be omitted here. According to the present embodiment, the number of viewpoints can be doubled by the 3D optical unit 30 and the liquid-optical element system 50. [ For example, when the 3D optical unit 30 separates an image into two viewpoints and the liquid optical element 40 of the liquid optical element system 50 separates the image into three viewpoints, can do.

Particularly, since the liquid optical element 40 can control the angle of the interface 12 between the polarized liquid 9 and the non-polar liquid 8 variously according to the electrical control, The number of viewpoints can be greatly increased. Furthermore, since the liquid optical element 40 changes the viewpoint by converting the optical path of the image generated by the image generator 20, the number of viewpoints can be increased without degrading the resolution.

Accordingly, the three-dimensional display device 100 to which the liquid-optical element system 50 is applied can realize a multi-viewpoint three-dimensional image without degrading the resolution.

4 shows an example of driving voltage waveforms applied to the liquid-optical element 40 driving method according to the embodiment of the present invention. That is, an example of driving voltage waveforms applied to the liquid-optical element 40 by the driving unit 15 in the liquid-optical element system 50 according to the embodiment of the present invention is shown.

4, the driving method of the liquid optical element 40 according to the embodiment of the present invention is such that when the contact angle changing operation of the liquid polar liquid 9 of the liquid optical element 40 is performed, The driving voltage of the two-stage structure of the voltage V2 and the second voltage V3 applied for a predetermined time T is applied and driven. At this time, the first voltage V2 corresponds to a voltage at the time of driving a general liquid optical element, and may be a predetermined value.

That is, if the driving voltage of the first voltage (V2) is applied for a predetermined period of time in order to change the contact angle of the polarized liquid at the time of driving the conventional liquid optical element, the driving of the liquid optical element 40 A driving voltage having a two-stage structure of a second voltage V3 held for a predetermined time T by the driving of the driving unit 15 and a first voltage V2 subsequent thereto is applied to the liquid optical element 40 . 1, the basic voltage V1 of the driving voltage is set so that when the polarizing liquid 9 and the interface 12 of the nonpolar liquid 8 form a plane perpendicular to the optical axis and the incident light is transmitted without refraction do.

The second voltage V3 is an overshoot voltage and the second voltage V3 is a voltage greater than or equal to 1.2 times the voltage of the first voltage V2, for example, 1.5 times greater than the first voltage V2. . The second voltage V3 may be 1.2 times to twice as large as the first voltage V1. The predetermined time T during which the second voltage V3 is applied may be 3 ms or less, for example, 0.1 to 3 ms.

Here, the time T during which the second voltage V3 is applied may be reduced when the material to be added to constitute the electrolyte in the polarized liquid 9 is well selected and the conductivity is increased.

The magnitude and the application time T of the second voltage V3 can be set within a range in which the contact angle stabilization time is less than or equal to 2 ms in the contact angle changing operation of the polarized liquid 9. [

For example, when driving an 8M pixel display device at 480 Hz to form 16 viewpoints, a time of about 16.7 ms is required for one frame, and a response time of about 2 ms is required.

The magnitude of the second voltage (V3) and the application time (T) can be determined so as to operate at a quick response time of about 2 ms or less and to realize a multi-view 3D image display device. When a second voltage V3 that is 1.2 times to twice larger than the first voltage V1 is applied for 3 ms or less, for example, 0.1 to 3 ms, in advance of the first voltage V1, A multi-viewpoint three-dimensional image display apparatus using the liquid optical element system 50 can operate under a quick reaction time of 2 ms or less.

The driving voltage may be applied at a fixed frequency f0. That is, the driving voltage can be applied at a predetermined time interval (1 / f0), and the slope of the interface 12 corresponding to the contact angle of the polarized liquid 9, that is, the first voltage V2 The magnitude of the second voltage V3 and the application time T of the second voltage V3 may be adjusted.

5 is a graph showing the relationship between the polarized liquid 9 of the liquid optical element 40 and the polar liquid 9 in accordance with the driving voltage application step when the driving voltage is applied according to the driving method of the liquid optical element 40 according to the embodiment of the present invention. 8) at the interface (12).

The interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 is controlled to form a flat horizontal surface at the voltage level of V1, that is, before the application of the driving voltage for adjusting the refracting direction of the light (The state of the interface 12 of the liquid optical element 40 on the left side in Fig. 5). When light is incident on the liquid-optical element 40, the light is transmitted straight without passing through the interface 12 between the polarizable liquid 9 and the non-polar liquid 8.

The driving voltage is applied to the liquid optical element 40 to vary the contact angle of the polarized liquid 9 so that the interface between the polarized liquid 9 and the nonpolar liquid 8 12, it may take time until the contact angle of the polarized liquid 9 becomes a desired value.

6A shows a driving voltage of a simple rectangular waveform as a comparative example. 6B shows the slope change of the interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 over time when a driving voltage of a simple rectangular waveform is applied to the liquid optical element 40. Fig. In FIG. 6B, the abscissa represents the reaction time, and the ordinate represents the change in the slope of the interface 12 between the polar liquid 9 and the nonpolar liquid 8 by the voltage.

6A, when a driving voltage of a simple rectangular waveform, that is, a driving voltage of only the second voltage, is applied to the liquid-optical element 40, as shown in FIG. 6A, It takes a time of about 7 ms, for example, for the contact angle of the substrate 9 to become a desired value. The reason why the reaction time is about 7 ms is because the polarized liquid 9 and the non-polar liquid are fluids, so that the polarized liquid 9 reacts with the driving voltage to change the contact angle, 8 takes a long time until the slope of the interface 12 reaches a desired position.

On the other hand, as in the driving method according to the embodiment of the present invention, the second voltage V3, which is an excessive voltage of the driving voltage by driving the driving unit 15, is first applied for a predetermined time T, V2) is applied, the reaction time can be greatly reduced.

That is, the slope of the interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 is changed more than the desired position while the second voltage V3, which is an excessive voltage, is applied for a predetermined time T first (The state of the interface 12 of the liquid-optical element 40 in the center of FIG. 5), and the first voltage V2 is applied thereto, the liquid crystal device 100 returns to a desired position and maintains a stable state The state of the interface 12 of the liquid-optical element 40).

According to the method of driving the liquid-optical element 40 according to the embodiment of the present invention, the reaction time can be greatly reduced, and the slope of the interface 12 of the polarized liquid 9 and the non- It can be stabilized within a time of 2 ms or less.

FIG. 7 is a graph showing the relationship between the first voltage V2 and the second voltage V3 by applying a driving voltage having a two-stage structure of 1.5 times, 1.7 times, and 2.0 times the transient voltage of the first voltage V2, FIG. 5 is a graph showing a change in settling time according to a transient voltage application time T when driving the liquid-optical element 40 according to an embodiment of the present invention. 7 shows that the slope of the interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 can be improved by using an electrolyte solution containing about 0.0085 wt% of polyacrylic acid (PAA) as the polarizable liquid 9, Optical element 40 is changed so as to change from 0 to 5 degrees.

According to the obtained results, when the transient voltage 1.5 times the first voltage V2, that is, the second voltage V3 is applied for 1.9 ms, the stabilization time takes about 1.4 ms. When the transient voltage 1.7 times the first voltage V2, that is, the second voltage V3, was applied for 1.7 ms, the stabilization time required about 1.2 ms. When a transient voltage 2.0 times greater than the first voltage V2, that is, the second voltage V3 was applied for 1.3 ms, the stabilization time required about 1.1 ms.

8 shows a time lapse when using a driving voltage to which a transient voltage is not applied and a driving voltage to which a transient voltage 1.5 times larger than the first voltage V2, i.e., a driving voltage to which the second voltage V3 is applied for 1.9 ms, Shows the slope change of the interface (12) between the polar liquid (9) and the nonpolar liquid (8). 8 shows that the slope of the interface 12 between the polarizable liquid 9 and the nonpolar liquid 8 can be improved by using an electrolyte solution containing about 0.0085 wt% of polyacrylic acid (PAA) as the polarizable liquid 9, Optical element 40 is changed so as to change from 0 to 5 degrees.

According to the obtained results, when using a driving voltage to which no transient voltage is applied, the reaction time is about 6.6 ms, while the transient voltage 1.5 times the first voltage V2, that is, the second voltage V3 is 1.9 When using the driving voltage applied for ms, the response time is greatly reduced to 1.4 ms.

As described above, according to the driving method of the liquid-state optical element 40 according to the embodiment of the present invention, the second voltage V3, which is the transient voltage, is applied for a predetermined time T by driving the driving unit 15 , And then the first voltage (V2) is applied, it is possible to adjust the angle of refraction of the light with a reaction time of 2 ms or less and a sufficiently fast reaction rate, It is possible to implement a point-based three-dimensional image display device.

1,6 ... substrate 2 ... barrier
3a, 3b ... Electrode 4 ... hydrophobic film
5 ... dielectric film 7 ... common electrode
8 ... non-polar liquid 9 ... polar liquid
100 ... display device 40 ... liquid optical element
10 ... prism cell

Claims (20)

Applying a voltage to a liquid optical element including a nonpolar liquid and a polarizable liquid disposed in a space surrounded by the barrier ribs and first and second electrodes disposed on side walls of the barrier ribs facing each other to change a contact angle of the polarizable liquid In the liquid optical element driving method,
Wherein the second voltage is driven by applying a driving voltage having a two-stage structure of a first voltage and a second voltage for a predetermined period of time before the polarity of the liquid is changed, Voltage is applied to the liquid-optical element. The liquid-optical element driving method according to claim 1, wherein the second voltage is 1.2 times larger than the first voltage. 3. The liquid-optical element driving method according to claim 2, wherein the second voltage is 1.5 times larger than the first voltage. 3. The method of claim 2, wherein the second voltage is 1.2 to 2 times larger than the first voltage. 5. The liquid-optical element driving method according to any one of claims 1 to 4, wherein the second voltage is applied for 0.1 to 3 ms. The liquid-optical element driving method according to any one of claims 1 to 4, wherein the second voltage is set within a range in which the contact angle stabilization time is less than or equal to 2 ms in a contact angle changing operation of the polarized liquid. The liquid-optical element driving method according to claim 1, wherein the driving voltage is applied at a fixed frequency. The liquid-optical element driving method according to claim 1, wherein the first voltage of the driving voltage is a predetermined voltage. 9. The method of any one of claims 1 to 4 or 7 to 8, further comprising: setting the second voltage to be greater than the first voltage;
And applying a driving voltage having a two-step structure of the first voltage and the second voltage applied thereto to change a contact angle of the polarized liquid. The liquid-optical element driving method according to claim 9, wherein the second voltage is applied for 0.1 to 3 ms. 10. The liquid-optical element driving method according to claim 9, wherein the second voltage is set within a range in which the contact angle stabilization time is 2 ms or less at the time of the contact angle changing operation of the polarized liquid. A non-polar liquid and a polarizable liquid disposed in a space surrounded by the barrier ribs, first and second electrodes disposed on the side walls of the barrier ribs facing each other, wherein the contact angle of the polar liquid is changed according to an applied voltage An optical element;
Applying a voltage to the liquid-optical element and applying a driving voltage having a two-step structure of a first voltage and a second voltage applied for a predetermined period of time and an excessive driving voltage relative to the first voltage, And a driving unit for driving the liquid-state imaging element to change the liquid-state imaging element. 13. The liquid optical element system according to claim 12, wherein the first voltage is a predetermined voltage. 13. The liquid-optical element system according to claim 12, wherein the second voltage is 1.2 times larger than the first voltage. 15. The liquid-optical element system according to claim 14, wherein the second voltage is 1.5 times larger than the first voltage. 15. The liquid optic element system of claim 14, wherein the second voltage is 1.2 to 2 times larger than the first voltage. 12. The liquid-optical element system according to claim 12, wherein the second voltage is applied for 0.1 to 3 ms. The liquid-optical element system according to claim 12, wherein the second voltage is set within a range in which the contact angle stabilization time is less than or equal to 2 ms in a contact angle changing operation of the polarized liquid. The liquid-optical element system according to claim 12, wherein the driving voltage is applied at a fixed frequency. An image generation unit for generating an image;
A liquid-optical element system according to any one of claims 10 to 19, configured to convert a path of light from the image generation unit;
And a 3D optical part provided between the image generating part and the liquid optical element of the liquid-optical element system for separating the viewpoint.

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