JPWO2006035482A1 - Liquid crystal device having optical zoom function and method of manufacturing the same - Google Patents

Abstract

In particular, it is an object of the present invention to provide a novel liquid crystal element which is used in a lens system of a camera mounted on a device such as a mobile phone and which can obtain an optical zoom function which is smaller, thinner and lighter than conventional ones. .. In order to solve this problem, a liquid crystal element of the present invention is a liquid crystal that is arranged with a lens on an optical axis to form an optical zoom system, and forms a refractive index distribution by applying a voltage to exhibit an optical zoom function. An element, comprising a liquid crystal and a plurality of electrodes facing each other with the liquid crystal sandwiched therebetween, and a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes is concentrically divided on the electrode. When the voltage is applied, the liquid crystal is formed in an arrangement pattern in which the size or the arrangement interval or both are changed along the radial direction, and the liquid crystal is non-uniformly aligned when a voltage is applied. To do.

Description

  The present invention relates to an optical zoom function. More specifically, the present invention relates to an optical zoom function suitably used for small digital still cameras, digital video cameras and the like in mobile phones, personal digital assistants (PDAs) and the like.

  2. Description of the Related Art In recent years, mobile phones with a photographing function, personal digital assistants (PDAs), etc., equipped with an ultra-small camera, have become widespread. In conventional miniature cameras, a single focus lens system was generally used due to size restrictions, but the camera specifications for mobile phones rapidly increased in number of pixels, and an effective pixel number of 1 to 2 million or more was standard. Along with this, it is required to have an optical zoom function, and recently, some optical compact zoom lenses have been proposed.

For example, in (Patent Document 1), a front lens group, a rear lens group, and an image pickup device such as a CCD are arranged in order on an optical axis, and only a rear lens group is driven by a driving unit in the direction of a guide pin (optical axis direction). An ultra-compact lens driving device is disclosed.
Further, in (Patent Document 2), in order from the object side to the image plane side, a first lens group having a negative refracting power as a whole, a second lens group having a positive refracting power as a whole, and And a third lens group having a positive refractive power, the second lens group moves from the image plane side to the object side, and the third lens group once moves from the image plane side to the object side and then again to the image plane side. There is disclosed a zoom lens that moves to the zoom position to perform zooming from the wide-angle end to the telephoto end and corrects an image plane variation due to zooming.

  The conventional zoom lens as described above can be downsized and thinned to some extent by devising the lens drive method, etc., but secures a movement space for mechanically moving the lens. However, in practice, the thickness of the lens barrel is limited to about 10 mm. Therefore, there is a problem that the degree of freedom in the external design of the mobile phone or the like is limited because it is necessary to avoid the protrusion of the lens portion, and in reality, the digital zoom method is still used. Also, as the number of effective pixels of the camera becomes higher, it becomes more and more important how to house the lens unit in a small housing.

JP, 2004-258111, A JP 2004-212737 A

  Therefore, in view of the conventional situation described above, the present invention is used for a lens system of a camera mounted on a device such as a mobile phone, and can obtain an optical zoom function which is smaller, thinner, and lighter than conventional ones. It is an object to provide a new liquid crystal element.

  In order to solve the above problems, the present invention provides, as a first invention, an optical zoom system by arranging a lens along an optical axis together with an optical zoom system to form a refractive index distribution by applying voltage. A liquid crystal element having a liquid crystal and a plurality of electrodes facing each other with the liquid crystal sandwiched therebetween, and configured so that the alignment state of the liquid crystal changes concentrically around the optical axis when a voltage is applied. Is provided.

  According to this configuration, a predetermined refractive index distribution is given to the entire element in accordance with the alignment state of the liquid crystal that changes concentrically, and the focal point moves to exert the optical zoom function.

  Further, in the second invention, a liquid crystal element is arranged on the optical axis together with a lens to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to exhibit an optical zoom function. , A plurality of electrodes facing each other across the liquid crystal, a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes, along a radial direction when the electrodes are concentrically divided. Provided is a liquid crystal element which is formed in an arrangement pattern in which the size and/or the arrangement interval are changed, and in which the liquid crystal is nonuniformly aligned when a voltage is applied inside the non-electrode portion.

  According to this structure, a weak electric field is formed in the central portion of the plurality of non-electrode portions in the direction perpendicular to the electrodes, and an electric field is formed in the inclined direction at the end portions of the non-electrode portions. Since the liquid crystal molecules are non-uniformly aligned along the electric field distribution, a light refraction effect (lens effect) in which the refractive index continuously changes from the center to the periphery of the non-electrode portion can be obtained. Since the size of the non-electrode portion or the arrangement interval is changed concentrically on the electrode, a predetermined refractive index distribution is given to the entire element, and the focus moves to exert the optical zoom function.

  According to the third aspect of the invention, the liquid crystal element is arranged on the optical axis together with a lens to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to exhibit an optical zoom function. , A plurality of electrodes facing each other across the liquid crystal, a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes, along a radial direction when the electrodes are concentrically divided. It is formed by an arrangement pattern in which the size and/or the arrangement interval are changed, and the inside of the non-electrode portion is configured so that the liquid crystal is non-uniformly aligned when a voltage is applied. Provided is a liquid crystal element in which linear electrodes are annularly arranged at a predetermined interval along the arrangement pattern that changes concentrically.

  According to this configuration, by changing the size or the arrangement interval of the non-electrode parts in a concentric manner as described above, a desired refractive index distribution can be obtained, and a plurality of linear electrodes are arranged in an annular shape. By further applying a voltage to the predetermined portion, the above refractive index distribution is further emphasized and the optical zoom function is improved.

  The fourth invention is that in the liquid crystal element according to the second invention or the third invention, the arrangement intervals of the plurality of non-electrode portions are irregular in each concentric region on the electrode. Characterize.

  According to this configuration, the distance between the adjacent non-electrode portions is irregular (random), so that the disturbance of the wavefront due to the optical interference effect is prevented.

  Further, a fifth invention is characterized in that, in the liquid crystal element according to the second invention or the third invention, the non-electrode portion has a circular shape or a pit shape.

  According to this structure, the shape of the non-electrode portion is optimized for the light flux passing through the element. Here, the pit shape means a shape in which one axis is longer than the other axis perpendicular to it, and for example, the longer axis is formed parallel to the rubbing direction of the liquid crystal or perpendicular to the rubbing direction. can do.

  According to the sixth aspect of the invention, the liquid crystal element is arranged on the optical axis together with a lens to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to exhibit an optical zoom function. , A plurality of electrodes facing each other with the liquid crystal interposed therebetween, and a plurality of linear electrodes applying different voltages to at least one of the plurality of electrodes concentrically with respect to the optical axis at predetermined intervals. The linear electrodes are arranged to act as a resistance film when a voltage is applied to the plurality of linear electrodes, and a voltage drop occurs between the plurality of linear electrodes. Provided is a liquid crystal element configured so that the alignment state of the liquid crystal changes concentrically around the optical axis.

  According to this configuration, the applied voltage is continuously changed between the plurality of linear electrodes, and the alignment state of the liquid crystal is changed according to the voltage value, so that a predetermined refractive index distribution is formed over the entire element. , Optical zoom function is demonstrated.

  A seventh invention is characterized in that, in the liquid crystal element according to the sixth invention, the electrode on which the plurality of linear electrodes are arranged is composed of a plurality of regions having different resistance values.

  According to this structure, in addition to the operation of the sixth invention, the voltage drop between the plurality of linear electrodes becomes curved.

  In addition, an eighth invention is characterized in that, in the liquid crystal element according to any one of the first to third, sixth, and seventh inventions, when the optical zoom system is configured, the outside of a region through which a light beam passes is shielded. And

  According to this structure, diffused reflection from the outside of the region through which the light flux passes is blocked, and the image quality of the image is stabilized.

  Further, in the ninth invention, it is composed of two liquid crystal elements laminated in the thickness direction, and is arranged with a lens on the optical axis to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to form an optical zoom system. A liquid crystal element having a double cell structure that exhibits a zoom function, wherein each of the liquid crystal elements is sandwiched between a pair of substrates having a common electrode formed on one side and a segment electrode formed on the other side, and the pair of substrates. And a plurality of non-electrode portions where no electrode material is present in the segment electrode, the size and/or the arrangement interval of the segment electrode being changed along the radial direction when the segment electrode is concentrically divided. The liquid crystal is arranged in a non-uniform manner when the voltage is applied inside the non-electrode portion, and a plurality of holes are formed in the thickness direction in each of the pair of substrates. A liquid crystal device having a double cell structure in which a terminal connected to either the common electrode or the segment electrode is provided in the hole, and an injection port for injecting liquid crystal is formed in one of the pair of substrates. I will provide a.

According to this structure, the terminals for connecting to the common electrodes and the segment electrodes, and the liquid crystal inlet are arranged on the surface of the substrate through the holes.
Further, as described above, since the liquid crystal molecules are non-uniformly aligned inside the plurality of non-electrode portions, a light refraction effect (lens effect) in which the refractive index changes from the center to the periphery of the non-electrode portion is generated. A concentric refractive index distribution is obtained for the entire device. Therefore, the focus moves and the optical zoom function is exerted.

  A tenth aspect of the invention is characterized in that, in the liquid crystal element having the double cell structure according to the ninth aspect, the alignment directions of the liquid crystal when no voltage is applied are orthogonal to each other in the two liquid crystal elements.

  According to this configuration, a predetermined refractive index distribution is given to different polarized lights (P polarized light and S polarized light).

  An eleventh aspect of the invention is a liquid crystal device having a double cell structure according to the ninth aspect, wherein the substrate is formed in a quadrangular shape, and the liquid crystal is sealed along a circular region through which the light flux of the substrate passes, the circular region. A liquid crystal injection port and a terminal are provided in the vicinity of the other corners.

  A twelfth aspect of the invention is a liquid crystal device having a double cell structure according to the tenth aspect of the invention, wherein the substrate is formed in a rectangular shape, and the liquid crystal is sealed along a circular area through which the light flux of the substrate passes, and the circular area is formed. A liquid crystal injection port and a terminal are provided in the vicinity of the other corners.

  According to the eleventh and twelfth aspects of the invention, the vicinity of the corner of the substrate is effectively used as a space for forming a hole, and the weight balance of the element is improved. Further, when the liquid crystal expands and contracts, the entire liquid crystal is uniformly deformed, so that the optical zoom function is stabilized.

  A thirteenth invention is a liquid crystal element having a double cell structure according to any one of the ninth to eleventh inventions, wherein terminals connected to a common electrode of each of the laminated liquid crystal elements are connected to each other, and a segment of one of the liquid crystal elements is connected. The terminals connected to the electrodes and the terminals connected to the segment electrodes of the other liquid crystal element are connected to each other in the thickness direction, and are provided on one substrate located outside the liquid crystal element of the double cell structure. It is characterized by being integrated into each terminal.

  A fourteenth aspect of the invention is a liquid crystal element having a double cell structure according to the twelfth aspect, wherein terminals connected to a common electrode of each of the stacked liquid crystal elements and terminals connected to a segment electrode of one of the liquid crystal elements. The terminals connected to each other and the segment electrodes of the other liquid crystal element are connected to each other in the thickness direction, and are gathered to the terminals provided on the outermost one substrate of the liquid crystal element having the double cell structure. It is characterized by

  According to the configurations of the thirteenth and fourteenth inventions, the terminals for driving the elements are collectively arranged on one substrate.

  A fifteenth aspect of the invention is a liquid crystal element having a double cell structure according to the fourteenth aspect, wherein a terminal connected to the segment electrode of one liquid crystal element and a terminal connected to the segment electrode of the other liquid crystal element are provided. It is characterized in that it is provided in the vicinity of a corner portion diagonally located on the rectangular substrate, and the terminal connected to the common electrode and the liquid crystal inlet are provided in the vicinity of the remaining corner portion.

  According to this configuration, the position of each terminal is set in consideration of efficiency in manufacturing the element.

  A sixteenth aspect of the invention is characterized in that, in the double-cell structure liquid crystal element according to any of the ninth to twelfth aspects of the invention, when the optical zoom system is configured, the light is shielded outside the region through which the light flux passes. To do.

  According to this structure, diffused reflection from the outside of the region through which the light flux passes is blocked, and the image quality of the image is stabilized.

  A seventeenth aspect of the invention is a method of manufacturing a liquid crystal device having a double cell structure according to the fifteenth aspect of the invention, wherein a step of providing terminals and injection ports corresponding to a large number of liquid crystal elements on a substrate as a base material. And a step of forming a segment electrode, and a step of providing another terminal having a common electrode with a terminal provided at a position facing the substrate having the terminals, the injection port, and the segment electrode formed thereon. After the step of injecting the liquid crystal from the injection port and the group in which a large number of liquid crystal elements manufactured through the above steps are arranged, another group obtained through the same steps is turned over and rotated by 90 degrees. A method of manufacturing a liquid crystal element having a double cell structure, comprising the steps of stacking layers above and dividing into individual liquid crystal elements having a double cell structure.

  An eighteenth invention is a method for manufacturing a liquid crystal device having a double cell structure according to the fifteenth invention, which comprises a step of providing terminals corresponding to a large number of liquid crystal devices on a substrate as a base material, and a segment. The step of forming electrodes, the step of forming terminals and injection ports at the positions facing each other with respect to the substrate on which the terminals and the segment electrodes are formed, and the step of combining another substrate on which common electrodes are formed, After injecting liquid crystal from the inlet and a set in which a large number of liquid crystal elements manufactured through the above steps are arranged, another set obtained through the same steps is turned over and rotated by 90 degrees. It is a method for manufacturing a liquid crystal device having a double cell structure, which includes a step of laminating and a step of cutting into individual liquid crystal elements having a double cell structure.

  According to the configurations of the seventeenth and eighteenth inventions, the production of the liquid crystal device having the double cell structure can be continued until the final step in the state of the substrate serving as the base material. Then, two liquid crystal elements in which the liquid crystal alignment directions are orthogonal to each other are manufactured by the same process.

  The nineteenth invention is the manufacturing method according to the seventeenth or eighteenth invention, wherein wiring for inspection commonly connected to each terminal is formed on the surface of the substrate, and a large number of liquid crystal elements are provided. Before the step of stacking another set with respect to the arranged set, or the step of cutting into individual double-cell structure liquid crystal elements, either or both of them are to be inspected using the wiring. Is characterized by.

  According to this structure, the operation of the elements is checked at once in the state of the base material before being divided into the individual elements.

  The twentieth invention is a manufacturing method according to the seventeenth invention or the eighteenth invention, wherein a circular shape through which a light flux passes in a vacuum when another set is laminated on a set in which a large number of liquid crystal elements are arranged. It is characterized in that the layers are laminated via a sealing material provided in a closed state so as to surround the region.

  According to this configuration, the space between the two liquid crystal elements is in a vacuum state and no adhesive is present, so that high light transmittance is maintained.

  The twenty-first invention is the manufacturing method according to the seventeenth or eighteenth invention, wherein a circular shape through which a light flux passes in the atmosphere when another set is laminated on a set in which a large number of liquid crystal elements are arranged. It is characterized in that the layers are laminated with a sealing material provided so as to partially surround the area and provided with an adhesive provided inside the sealing material.

  According to this configuration, the step of stacking the two liquid crystal elements is efficiently performed in the atmosphere. In this case, it is preferable to select an adhesive having a refractive index close to that of the substrate.

The liquid crystal element of the present invention produces a refraction effect of light by forming a plurality of non-electrode parts on electrodes and orienting the liquid crystal molecules along the nonuniform electric field distribution formed at the positions of the non-electrode parts. Let Thereby, a continuous refractive index distribution can be formed in the entire element. Since this refractive index distribution can be changed arbitrarily by controlling the alignment state of the liquid crystal by the applied voltage, it is possible to perform the optical zoom function by moving the focus when placed on the optical axis. it can.
According to the present invention, it is possible to provide a compact and thin optical zoom function which has not been available in the past, because it is not necessary to drive the lens in the optical zoom system or a minimum drive is required, and it is particularly suitable for an ultra-small camera such as a mobile phone. Can be used.

  Further, in the liquid crystal element of the present invention, the size and arrangement interval of the plurality of non-electrode portions are changed according to the position on the electrode, and the plurality of linear electrodes are arranged at predetermined intervals along the arrangement pattern of the non-electrode portions. It is characterized in that it is provided. As a result, the change in the refractive index obtained by the non-electrode portion becomes large at a plurality of places where the linear electrodes are arranged, and the refractive index distribution due to the non-electrode portion is more emphasized as a whole. it can.

  In addition, the liquid crystal element of the present invention has a plurality of linear electrodes arranged on the resistance film, and the alignment state of the liquid crystal is changed concentrically by utilizing the voltage drop between the linear electrodes. A predetermined refractive index distribution can be formed. This refractive index distribution can be arbitrarily controlled by the voltage applied to the linear electrode, and when it is arranged on the optical axis, the focal point can be moved to exert the optical zoom function.

  Further, in the liquid crystal element of the double cell structure according to the present invention, since a hole is formed in the surface of the substrate and the hole portion is used as a terminal, an unreasonable force is applied to the substrate as compared with the case where the terminal is provided on the side. There is no. Therefore, a thinner substrate can be adopted, and as a result, the weight and size of the element can be reduced.

  In addition, since the liquid crystal is sandwiched in the center of the quadrangular substrate and terminals are provided at the corners of the substrate, the weight balance of the element is excellent, and even if the liquid crystal expands or contracts due to temperature change, it will be deformed unevenly. Does not occur, and the performance of the device can be maintained.

Further, according to the method for manufacturing a liquid crystal element having a double cell structure according to the present invention, the step of forming terminals, the step of injecting liquid crystal, etc. are all performed in the state of the base material before being cut into individual elements. Therefore, the production efficiency can be improved and the cost can be significantly reduced.
Further, when each element is inspected, it can be performed in the state of the base material, so that high efficiency can be achieved.
Furthermore, two liquid crystal elements to be laminated can be manufactured in exactly the same process, and by simply turning one side over and rotating it by 90 degrees, a liquid crystal element having a double cell structure in which liquid crystal alignment directions are orthogonal can be easily produced. You can Therefore, productivity is extremely high and stable quality can be obtained.

It is a figure which shows typically the usage pattern of the liquid crystal element which concerns on Embodiment (1). 3 is a plan view of the liquid crystal element according to the embodiment (1). FIG. It is an enlarged view of the A portion of FIG. 3 is a cross-sectional view of the liquid crystal element according to the embodiment (1). FIG. It is a figure explaining the state at the time of voltage application of the liquid crystal element concerning Embodiment (1). FIG. 6 is a plan view of a liquid crystal element according to an embodiment (2). 6 is a plan view of a liquid crystal element according to Embodiment (3). FIG. It is a figure which shows typically the refractive index distribution obtained by the liquid crystal element which concerns on Embodiment (3). It is a figure explaining the manufacturing process of the liquid crystal element which concerns on Embodiment (3). FIG. 6 is a plan view of a liquid crystal element according to an embodiment (4). It is a plan view of a liquid crystal element according to an embodiment (5). It is a figure explaining the manufacturing process of the liquid crystal element which concerns on Embodiment (5). It is a plan view of a liquid crystal element having a double cell structure according to an embodiment (6). It is CC sectional drawing of FIG. FIG. 14 is a cross-sectional view taken along the line DD of FIG. 13. It is a figure which shows typically the usage mode of the liquid crystal element of the double cell structure which concerns on Embodiment (6). 7 is a flowchart showing a manufacturing process of a liquid crystal device having a double cell structure. 7 is a flowchart showing a manufacturing process of a liquid crystal device having a double cell structure. It is a figure which shows the state of S103 in the S direction of FIG. It is sectional drawing of a terminal part which shows the state of S103. It is a figure which shows the state of S106 in the S direction of FIG. It is a figure which shows the state of S108 in the S direction of FIG. It is a figure which shows the state of S205 in the T direction of FIG. It is a figure which shows the state of S104 in the U direction of FIG. It is a figure which shows the state of S501. It is a figure which shows the state of S305. It is a figure which shows the state of S504. It is a figure which shows another example of the state of S305. 9A and 9B are a plan view and a side view of a liquid crystal element having a double cell structure according to an embodiment (7).

Explanation of symbols

1A to 1G Liquid crystal element 1FG Liquid crystal element 10 with double cell structure Liquid crystal 20, 21 Electrode 22 Segment electrode 23 Common electrode 24 High resistance film 24a High resistance zone 24b Medium resistance zone 24c Low resistance zone 201 Non-electrode parts 30, 31, 32 , 33 substrate 32a light-shielding portion 32b corner portion 320 base material substrate 330 base material substrate 40a to 40d linear electrode 400 low resistance film 400a low resistance film 50 SiO ₂ films 60A to 60F holes 61A to 61F terminals 70, 71 , 71A Seal material 72 Adhesive 73 Injection port 74 Sealant 75 Conductive material 76 Mask 77 Wiring E Electric field F, F'Focus J Lens L Optical axis M Image planes P1, P2 Polarization planes R1 to R3 Resistors S1, S2 Terminal P , Q Refractive index distribution

  Hereinafter, the present invention will be described in detail. In addition, in the following embodiments, the same components are denoted by the same reference numerals and description thereof is omitted.

  First, an embodiment (1) of the present invention is shown in FIGS. FIG. 1 is a diagram schematically showing a usage pattern of a liquid crystal element 1A according to this embodiment (1), FIG. 2 is a plan view of the liquid crystal element 1A, and FIG. 3 is an enlarged view of a portion A of FIG. 4 is an enlarged view of the cross section of the liquid crystal element 1A.

  As shown in FIG. 1, the liquid crystal element 1A is preferably used particularly for a small camera such as a mobile phone or a personal digital assistant (PDA), and an optical axis L with respect to an image plane M provided with CCD, CMOS or the like. The lens system is arranged on the upper side together with the lens J. Then, by applying a voltage to the element, a refractive index distribution is formed mainly in the surface direction of the element (perpendicular to the optical axis), and the focal point F is moved to the focal point F′ (or vice versa) to perform optical conversion. It has a zoom function. Since the light incident on the liquid crystal element 1A is polarized, a polarizer can be arranged on the optical axis L as necessary. Hereinafter, the configuration of the liquid crystal element 1A will be described in detail.

  As shown in FIG. 4, the liquid crystal element 1A includes a liquid crystal 10, two electrodes 20 and 21 facing each other with the liquid crystal 10 sandwiched therebetween, and substrates 30 and 31, and a plurality of electrodes 20 having no electrode material. The non-electrode part 201 is formed in a hole shape. In FIG. 4, an antireflection film (AR film) provided on the substrates 30 and 31, a liquid crystal alignment film generally provided between the electrodes 20 and 21 and the liquid crystal 10, a transparent insulating layer and the like are shown. Omitted. Further, a lead wire or the like is connected to the electrodes 20 and 21 to apply a voltage.

  As shown in FIG. 2, the plurality of non-electrode portions 201 continuously change in size and arrangement interval depending on the position on the electrode 20. Note that the number of non-electrode portions 201 is illustrated small in FIG. 2 for convenience, but in reality, many non-electrode portions 201 are finely formed as shown in FIG. In this embodiment (1), the size d1 of the non-electrode portion 201 is changed from a large diameter to a small diameter along the radial direction R when the electrode 20 is divided into concentric circles. A continuous pattern is formed such that the arrangement interval d2 is changed from a wide interval to a narrow interval.

  When a voltage is applied between the electrodes 20 and 21, the state of the electric field E near the non-electrode portion 201 is as shown in FIG. That is, in the portion a where the electrode 20 and the electrode 21 face each other, a strong electric field is formed in the direction perpendicular to the electrode, and in the portion b which is the central portion of the non-electrode portion 201, the electric field is also weak in the direction perpendicular to the electrode. An electric field is created. Then, in the portion c near the boundary between the non-electrode portion 201 and the electrode 20, the electric field is inclined toward the electrode 20.

Then, when the dielectric anisotropy of the liquid crystal 10 is positive, the liquid crystal molecules are aligned along the electric field E, so that the liquid crystal molecules are aligned perpendicular to the electrodes in the portion a and the electric field is weak in the portion b. It remains parallel to the electrodes, and is obliquely oriented in the portion c. That is, the liquid crystal becomes non-uniformly aligned inside the non-electrode portion 201. At this time, the refractive index for light (extraordinary light) that passes through the element forms a distribution that continuously decreases from the center of the non-electrode portion 201 to the periphery, so that the effect of the convex lens is present in the non-electrode portion 201. Will be shown. Thereby, a phase difference can be given to the passing light.
Therefore, as shown in FIG. 2, when the size and the arrangement interval of the non-electrode portions 201 are continuously changed depending on the positions on the electrodes, the phase difference obtained at each position is different, so that the entire element has a predetermined refraction. The ratio distribution can be obtained, and as a result, the focal length of the lens system can be changed and the optical zoom function can be obtained.

  When the applied voltage is changed, the alignment state of the liquid crystal molecules is changed accordingly. For example, when the voltage is increased, the liquid crystal molecules are vertically aligned even in the center of the non-electrode portion 201, and conversely, a concave lens effect that the refractive index increases from the center to the periphery of the non-electrode portion 201 is exhibited. .. That is, since the refractive index distribution obtained in the entire element can be changed by the applied voltage, calculate the necessary refractive index distribution for the set focal length and control the voltage according to the result. The focal length can be changed continuously with.

Furthermore, it is preferable that the arrangement intervals of the non-electrode portions 201 be irregular (random arrangement) within each of the concentrically divided regions on the electrode 20 (for example, the region X and the region Y). That is, as shown in FIG. 3, the arrangement intervals h1 and h2 are made slightly different. By doing so, it is possible to prevent a situation in which lights passing through the adjacent non-electrode portions interfere with each other to disturb the wavefront.
When it is expected that there is almost no interference effect due to the relationship between the wavelength of light and the arrangement interval, h1 and h2 may be the same and arranged regularly.

  As the electrodes 20 and 21, a conventionally known general electrode can be used. Specifically, an ITO electrode having an indium-tin oxide film formed on the transparent substrates 30 and 31 is preferably used.

  As a method of forming the non-electrode portions 201, a method of first forming the electrodes 20 on the entire surface of the substrate 30 and then forming a plurality of non-electrode portions 201 in a desired arrangement pattern by a photo process is preferably used. .. By doing so, it is possible to easily create a fine arrangement pattern that continuously changes. Alternatively, a method may be used in which the electrode 20 is vapor-deposited or plated on the substrate 30 through a mask.

  FIG. 6 shows an embodiment (2) of the present invention. In the liquid crystal element 1B, a plurality of non-electrode portions 201 are formed on the electrode 20 as in the above-described embodiment (1), but the non-electrode portions 201 have the same diameter. Then, the arrangement intervals of the non-electrode portions 201 are continuously changed from a wide interval to a narrow interval from the center of the electrode 20 toward the periphery. As described above, when the non-electrode portions 201 are arranged in a dense and dense manner, due to the refraction effect (lens effect) of light in each non-electrode portion when a voltage is applied, the non-electrode portions 201 are dense and thin. The obtained phase difference is different from that of the region, and a predetermined refractive index distribution can be obtained in the entire device.

  Next, an embodiment (3) of the present invention will be described with reference to FIGS. In the liquid crystal element 1C of FIG. 7, a plurality of non-electrode portions 201 are formed on the electrodes 20 sandwiching the liquid crystal, and the size and arrangement interval of the non-electrode portions 201 are set in the radial direction R, as in the above-described embodiment (1). Is changing continuously. The present embodiment (3) is characterized in that the annular linear electrodes 40a to 40d are arranged along the arrangement pattern of the non-electrode portions 201 (the pattern changing concentrically).

The linear electrodes 40a to 40d are connected to the terminals S1 and S2, and are configured to apply different voltages by using the resistors R1 to R3.
The refractive index distribution obtained by this liquid crystal element 1C is schematically shown in FIG. As shown in FIG. 8, when the refractive index distribution P is obtained by the lens effect of the non-electrode portion 201, the liquid crystal is more aligned in the portions s, t, u, v where the linear electrodes 40a to 40d are arranged, As a result, the phase difference is increased by a predetermined amount, and as a result, the refractive index distribution Q is emphasized and the refractive index distribution Q is obtained. Therefore, it becomes possible to widen the zoom range. Here, the positions at which the linear electrodes 40a to 40d are arranged and the voltage value applied to each can be determined based on the refractive index distribution P caused by the non-electrode portion 201. That is, it is preferable to set a voltage value proportional to the amount of phase change in each part of the refractive index distribution P. For example, when a voltage of 1 V is applied between the terminals S1 and S2, the linear electrode 40a (v in FIG. 1 V for the linear electrode 40b (corresponding to u), 0.6 V for the linear electrode 40b (corresponding to u), 0.1 V for the linear electrode 40c (corresponding to t), and 0 V for the linear electrode 40d (corresponding to s). The resistors R1 to R3 can be set so that the applied voltage becomes. Needless to say, the linear electrodes 40a to 40d are not limited to the circuit configuration shown in FIG.

FIG. 9 shows an example of a manufacturing process of the liquid crystal element 1C according to Embodiment (3). First, as shown in FIG. 9A, electrodes such as ITO (low resistance film 400, several to several tens of Ω) are formed on a glass substrate 30. In this example, the SiO ₂ film 50 is formed between the substrate 30 and the low resistance film 400. This film is a passivation film that prevents elution of sodium from the substrate 30, and can be provided as necessary.

  Subsequently, as shown in FIGS. 9B and 9C, the low-resistance film 400 is patterned to form a linear electrode 40a, and an electrode 20 such as ITO (high-resistance film, several tens or more) is formed thereon. A few hundred kΩ). Then, as shown in FIG. 9D, a plurality of non-electrode portions 201 are formed at predetermined positions to obtain a target substrate on which the linear electrodes 40a (40b to 40d) and the electrode 20 are formed. be able to. Since the linear electrode 40a is extremely thin (several to several tens of μm) as compared with the size of the element, it may be made of an opaque metal other than ITO in some cases.

  The arrangement pattern of the plurality of non-electrode parts 201 is not limited to the above-mentioned embodiments (1) to (3). That is, the size and/or arrangement interval of the non-electrode portions 201 or both of them can be appropriately set depending on the position on the electrode 20 according to a desired refractive index distribution and the like. Specifically, for example, when the size of the non-electrode portion is continuously changed from the small diameter to the large diameter from the center to the periphery of the electrode 20 contrary to FIG. 2, or contrary to FIG. The case where the arrangement interval of the non-electrode portions is continuously changed from the narrow interval to the wide interval from the center of the electrode 20 to the periphery is mentioned.

Although the non-electrode portion 201 is formed only on the electrode 20 in each of the above-described embodiments, the non-electrode portion may be formed on both the electrode 20 and the electrode 21. In this case, since the liquid crystal molecules are non-uniformly aligned even near the electrode 21, the obtained lens effect becomes stronger and the optical zoom function can be improved.
Further, the electrode 20 may be composed of several divided electrodes, a plurality of non-electrode portions may be formed in each electrode, and different voltages may be applied to the electrodes to give a more complicated refractive index distribution as a whole. it can.

  In addition, in the above-described Embodiments (1) to (3), the case where the plurality of non-electrode portions 201 has a circular shape has been described, but the present invention is not limited to this. For example, the type of generated aberration, the rubbing direction, etc. Other shapes can be taken into consideration. Specific examples include a pit shape, an elliptical shape, and a semicircular shape.

  Next, an embodiment (4) of the present invention will be described with reference to FIG. In the liquid crystal element 1D of FIG. 10, as in the above-described embodiment (3), a plurality of linear electrodes 40a to 40d to which different voltages are applied are arranged concentrically around the optical axis at predetermined intervals. is doing. Here, the linear electrodes 40a to 40d of FIG. 10 are provided on the high resistance film 24, but the high resistance film 24 is the same as the electrode 20 in the above-described embodiments (1) to (3), It is made of ITO or the like (unlike the electrode 20, it is called a high resistance film because no voltage is applied).

  In the liquid crystal element 1D, when a voltage is applied to the linear electrodes 40a to 40d, a voltage drop occurs due to the high resistance film 24 between the linear electrodes. Therefore, the liquid crystal has different alignment states depending on the voltage that continuously changes concentrically, and accordingly, a predetermined refractive index distribution is obtained. Since this refractive index distribution can be arbitrarily controlled by changing the voltage applied to the linear electrodes 40a to 40d, it is possible to obtain the desired optical zoom function.

FIG. 11 shows a liquid crystal element according to Embodiment (5). In this liquid crystal element 1E, a resistance film on which a plurality of linear electrodes 40a to 40d are arranged is composed of a plurality of regions (high resistance zone 24a, medium resistance zone 24b, low resistance zone 24c) having different resistance values. It is characterized by doing.
By doing so, for example, inside the linear electrode 40c, the voltage of the linear electrode 40c sharply drops due to the high resistance zone 24a, and then enters the middle resistance zone 24b, and the slope of the voltage drop becomes small. Finally, the low resistance zone 24c allows the voltage drop to be moderated and the voltage to be connected to the central linear electrode 40d, and as a result, the refractive index distribution can be made more curved.

FIG. 12 shows an example of a manufacturing process of the liquid crystal element 1E according to the embodiment (5). First, as shown in FIG. 12A, a low resistance film 400 (several to several tens Ω) such as ITO is formed on a glass substrate 30. In this example, the SiO ₂ film 50 is formed between the substrate 30 and the low resistance film 400. Subsequently, as shown in FIG. 12B, the low resistance film 400 is patterned to form the linear electrode 40a and a plurality of fine low resistance films 400a.
Next, as shown in FIG. 12C, a high resistance film 24 (several tens to several hundreds kΩ) is formed, and as shown in FIG. A plurality of non-electrode parts are formed at the positions. This makes it possible to obtain a plurality of regions having different resistance values. That is, the region where the non-electrode portion is formed in a part of the high resistance film becomes the high resistance zone 24a, the region where the uniform high resistance film is formed becomes the middle resistance zone 24b, and the low resistance film is formed in a part thereof. The low resistance zone 24c is formed in the region.

  In the above-described embodiments (4) and (5), the plurality of linear electrodes can be arranged also on the other substrate side facing each other with the liquid crystal interposed therebetween.

  Further, in the above embodiments (1) to (5), the electrodes facing each other are not limited to one pair, and more electrodes may be stacked while sandwiching the liquid crystal. For example, as shown in FIG. 1, a plurality of liquid crystal elements 1A (two in the figure) can be used in combination. In this case, different liquid crystal elements 1A have different lens effects (refractive index distributions) by changing the arrangement pattern of the non-electrode parts or making the applied voltage different, thereby obtaining a more complicated optical zoom function. be able to.

  Next, an embodiment (6) of the present invention will be described. FIG. 13 is a plan view of a liquid crystal element having a double cell structure according to Embodiment (6) of the present invention. 14 is a sectional view taken along line CC of FIG. 13, and FIG. 15 is a sectional view taken along line DD of FIG. As shown in FIGS. 13 to 15, in the liquid crystal element 1FG having a double cell structure, two liquid crystal elements 1F and 1G having the same structure are laminated in the thickness direction with a conductive material 75 and a sealing material 71 interposed therebetween. It is composed of Then, the liquid crystal element 1F (same for 1G) is roughly configured by sandwiching the liquid crystal 10 between the substrate 33 on which the common electrode 23 is formed and the substrate 32 on which the segment electrode 22 is formed. The liquid crystal alignment film, the transparent insulating layer and the antireflection film provided on the substrates 32 and 33, which are generally provided between the common electrode 23 and the liquid crystal 10 and between the segment electrode 22 and the liquid crystal 10, are not included. Illustration is omitted. Further, the liquid crystal 10 is sealed inside by a sealing material 70.

In the liquid crystal element 1FG having the double cell structure, a plurality of non-electrode parts (not shown) are formed on the segment electrodes 22 and the non-electrode parts of the non-electrode parts are formed in the same manner as in the above-described embodiments (1) to (3). The size and arrangement interval are changed concentrically. Therefore, as shown in FIG. 16, by disposing this element along with the other lens J on the optical axis L and applying a voltage between the common electrode 23 and the segment electrode 22, refraction caused by the non-electrode portion is caused. An optical zoom function can be exerted by generating a rate distribution and changing the focus F to the focus F′ (or vice versa).
The configuration of the non-electrode portion and each electrode is based on the description of the above embodiment (1).

  Further, particularly in the present embodiment (6), the alignment directions of the liquid crystal 10 of the liquid crystal elements 1F and 1G when no voltage is applied are orthogonal to each other. As a result, the wavefronts of different polarization planes P1 and P2 (corresponding to P-polarized light and S-polarized light) of the light flux passing through the lens system can be similarly changed, and the image quality of the image can be further improved.

  In this embodiment (6), holes 60A, 60B and 60C are formed in the thickness direction of the substrate 32, and holes 60D, 60E and 60F are also formed in the substrate 33. Terminals 61A, 61B, 61C, 61D, 61E, and 61F for connecting to the common electrode 23 and the segment electrode 22 are provided in the respective holes, respectively. That is, the terminals 61A and 61D are connected to the segment electrode 22 of the liquid crystal element 1F, the terminals 61B and 61E are connected to the common electrode 23, and the terminals 61C and 61F are connected to the segment electrode 22 of the liquid crystal element 1G. Between the terminals which face each other (for example, the terminal 61B and the terminal 61E), a conductive material 75 is interposed and connected. Each terminal is formed by plating a metal such as Ni-Au along the inner peripheral surface of the hole.

  By arranging the terminals on the surfaces of the substrates 32 and 33 as described above, compared to a case where the terminals are collectively arranged on the side of the substrate, a biased force is not applied to the element, and cracks, chips, etc. do not occur. Defects are less likely to occur. Therefore, the substrates 32 and 33 can be made thinner (for example, 0.2 mm), and the element can be made lighter. Therefore, the entire optical zoom system can be made smaller.

Further, in this embodiment (6), an injection port 73 for injecting the liquid crystal 10 between the substrates 32 and 33 is formed on the surface of the substrate 32. The injection port 73 has a circular shape, an elliptical shape, or the like, and is appropriately sealed with a sealing material 74 after the liquid crystal 10 is injected.
In particular, in the example of FIG. 13, the terminals 61A to 61F and the liquid crystal injection port 73 are all arranged on the surfaces of the substrates 32 and 33, and the opposing terminals are connected to each other in the thickness direction. Since the driving terminals provided in the liquid crystal element 1F are integrated, the element production efficiency can be increased as described later.

  Further, in the example of FIG. 13, the holes 60A to 60F and the liquid crystal injection port 73 are formed in a quadrangular shape other than the circular area (the area where the segment electrode 22 and the common electrode 23 are formed) through which the light flux passes. It is formed near the corner 32b on the substrate 32 (33). Further, the sealing material 70 is provided in a substantially circular shape so that the liquid crystal 10 is sealed in the circular area through which the light flux passes. With this configuration, the excess portion of the substrate 32 through which the light flux does not pass can be effectively used as the position of the terminal or the like, and thus the element can be further downsized. Further, by arranging the terminals and the like at the corner portion 32b, the weight balance of the element can be optimized. As a result, highly accurate driving becomes possible, and when the liquid crystal expands/contracts due to temperature change, uniform pressure is applied to the substrate 32 so that non-uniform deformation does not occur and element performance is maintained. You can

  Further, in the example of FIG. 13, the pattern of the segment electrode 22 is formed so as to be directly connected to the terminal 61A, but in addition to this, for example, after forming each electrode pattern formed of a closed circular region, Each electrode and each terminal may be connected by a lead wire or the like.

  Next, a method of manufacturing the liquid crystal element 1FG having the double cell structure according to the example of FIG. 13 will be described with reference to FIGS.

  First, a process of processing the substrate 32 in the liquid crystal correction element 1F will be sequentially described. 19 to 22 show a state viewed from the S direction in FIG. First, as shown in FIG. 17 and FIG. 19, holes 60A, 60B, and 60C corresponding to a large number of liquid crystal elements and liquid crystal injection holes 73 are formed at predetermined positions in a substrate 320 that is a base material. Yes (S101). Subsequently, after forming an antireflection film (AR film) on the entire surface of the substrate 320 as a base material (S102), terminals 61A, 61B and 61C are provided in the respective holes (S103). As will be described later, since the terminals 61A to 61C need to overlap each other when the substrate 320 is turned upside down and rotated by 90 degrees, the substrate 320 serving as a base material is preferably square, and many terminals are arranged. The same number of liquid crystal elements are formed vertically and horizontally. When providing each terminal (for example, the terminal 61A), as shown in FIG. 20, after forming a mask 76 on a portion other than the hole 60A, a metal to be the terminal 61A is formed by plating or the like, and then a mask is formed. This is preferably done by removing 76.

  Subsequently, on the side viewed from the U direction in FIG. 14, after forming a wiring used for an inspection as described later (S104), an electrode material is formed at a predetermined position by vapor deposition or the like (S105), and by etching or the like. Patterning is performed to produce the segment electrode 22 (S106). This state is shown in FIG. Note that the step of providing the terminal and the step of forming the wiring used for the inspection may be performed before or after.

  Next, a transparent insulating layer is laminated on the side in the S direction as needed, a liquid crystal alignment film such as PVA is formed, and rubbing is performed (S107). Further, a sealing material 70 for enclosing the liquid crystal is provided outside the segment electrodes 22 by printing or the like (S108). This state is shown in FIG.

On the other hand, as for another substrate (on the side of the substrate 33) to be opposed, as shown in FIG. 23 viewed from the T direction of FIG. 14, the hole 60D is formed at the same position as the substrate 320 with respect to the substrate 330 which is the base material. After forming 61E and 60F (S201) and forming an AR film (S202), terminals 61D, 61E and 61F are provided (S203), electrode materials are vapor-deposited (S204), and patterning is performed to perform common. The electrode 23 is formed (S205). In addition, a liquid crystal alignment film is formed and rubbing is performed (S206), and a conductive material for connecting the terminals of the substrate 320 facing each other is provided by printing or the like (S207).
In some cases, the injection port 73 may be formed on the substrate 33 side, or the sealing material 70 may be printed on the substrate 33 side and the conductive material may be printed on the substrate 32 side.

Then, the substrate 320 and the substrate 330 having the terminals and the like as described above are opposed to each other and combined (S301). This step is performed by bonding with an adhesive via a spacer.
Subsequently, liquid crystal is injected from the injection port 73 into the inside of the sealing material 70 (S302), and is sealed by the sealing material. Then, the operation inspection of the element is performed using each terminal arranged on the substrate 320 which is the base material (S303). At this time, since the wiring 77 is previously formed on the substrate 320 as shown in FIG. 24 (S104), 100% inspection is performed at once using the wiring 77. NG marking is performed on a portion that fails the inspection (S304).

  Through the above steps (S101 to S303), a set in which a large number of liquid crystal elements 1F are arranged is obtained. Then, another set (where the liquid crystal elements 1G are arranged) manufactured through the same steps (S101 to S303) is laminated on this set (S501). At this time, as shown in FIG. 25, another set is turned over in the Z direction and rotated by 90 degrees in the X direction, and the liquid crystal element 1G and the substrate 330 side of the set in which the liquid crystal elements 1F are arranged are arranged. By stacking the substrate 330 side of the set, the common terminals and the corresponding segment terminals are combined with each other, and a state in which the alignment directions of the liquid crystals are orthogonal to each other can be obtained.

  Further, when stacking the sets, the sealing material 71 and the conductive material 75 are printed in advance between the sets (S305, S401). The sealing material 71 and the conductive material 75 may be provided on the liquid crystal element 1F side or on the opposite liquid crystal element 1G side.

  As shown in FIG. 26, the sealing material 71 can be provided in a closed state so as to surround a circular area through which the light flux passes. In this case, the work of stacking the pairs must be performed in a vacuum so that the stacked state is not impaired by the expansion of the gas trapped inside the sealing material 71. It is preferable that the sealing material 71 is closed and the inside is in vacuum because dust or the like does not enter the inside and the light transmittance can be increased.

  Then, after stacking the pairs, an operation test of the liquid crystal element having the double cell structure is performed using each terminal arranged on the substrate 320 as a base material (S502). At this time as well, as in the case described above, the wiring 77 formed on the substrate 320 can be used to perform a 100% inspection at one time. NG marking is performed on a portion that fails the inspection (S503).

  Finally, as shown in FIG. 27, the base material substrate is cut into individual double liquid crystal elements 1FG using a dicer or the like (S504), and a single product inspection step (S505) is performed before shipment (S507). .. It should be noted that the element that fails the inspection of the single item is either discarded, repaired, or moved to the recycling step (S506).

  When stacking the pairs, instead of the sealing material 71 shown in FIG. 26, a sealing material 71A provided in a partially opened state so as to surround a circular region through which a light flux passes, as shown in FIG. You may intervene. In this case, an adhesive 72 is provided inside the sealing material 71A, and the sets are adhered to each other by the adhesive 72. In the example of FIG. 28, the work of stacking the sets can be performed in the atmosphere, which has an advantage of high production efficiency.

According to the manufacturing method as described above, since the steps of forming each terminal and electrode, and the step of injecting liquid crystal are all performed in the state of the base material before being cut into individual elements, the production efficiency is very high and the cost is high. Can be significantly reduced. Moreover, it is possible to easily cope with the expansion of the production scale.
In particular, two liquid crystal elements to be laminated are not manufactured separately but manufactured in the same process, and it is sufficient to turn over one side and rotate 90 degrees, so that the overall production efficiency is greatly improved.
Further, the inspection process performed after injecting and sealing the liquid crystal can be performed all at once in the state of the base material, which is extremely useful in industry.

  Next, an embodiment (7) of the present invention will be described with reference to FIG. In the example of FIG. 29, with respect to the liquid crystal element 1FG having the double cell structure described above, the light shielding portion 32a is provided outside the region through which the light flux passes when the optical zoom system is configured (the circular region in which the segment electrodes 22 are provided). It is characterized by being formed. The portions of the terminals 61A to 61C are omitted. The light-shielding portion 32a can be formed by an appropriate means, for example, a method of providing a black coating film on the surface and the end surface of the substrate 32, or a black sealing material when laminating the liquid crystal elements 1F and 1G. A method of mixing a pigment or the like can be appropriately used.

According to this embodiment (7), since the light-shielding portion 32a shields diffused reflection from outside the element (in particular, light incident in the surface direction from the end face of the substrate 32), a good image can be maintained. The light shielding portion 32a in this embodiment (7) can also be applied to the liquid crystal elements according to the above embodiments (1) to (5).
Further, in the example of FIG. 29, the four corners of the substrate 32 are cut obliquely. In this case, the shape is close to the outer shape (round shape) of another lens, which is preferable because the entire lens system can be made smaller. There is also an advantage that the element can be lightened by the amount of cutting.

  Since the liquid crystal element of the present invention can form a predetermined refractive index distribution, it is not necessary to drive the lens when it is arranged in the optical zoom system, or it can be driven with a minimum, so that it is possible to realize a smaller size than ever before. It can provide a thin optical zoom function, and can be suitably used particularly for an ultra-small camera such as a mobile phone.

[0002]
The current situation is that it relies on the boom system. Also, as the number of effective pixels of the camera becomes higher, it becomes more and more important how to house the lens unit in a small housing.
[0005]
[Patent Document 1] JP-A-2004-258111 [Patent Document 2] JP-A-2004-212737 [Disclosure of the Invention]
[Problems to be Solved by the Invention]
[0006]
Therefore, in view of the conventional situation described above, the present invention is used for a lens system of a camera mounted on a device such as a mobile phone, and can obtain an optical zoom function which is smaller, thinner, and lighter than conventional ones. It is an object to provide a new liquid crystal element.
[Means for Solving the Problems]
[0007]
In order to solve the above-mentioned problems, the present invention is a liquid crystal element that is arranged together with a lens on an optical axis to form an optical zoom system and forms a refractive index distribution by applying a voltage to exert an optical zoom function. And a liquid crystal and a plurality of electrodes facing each other with the liquid crystal sandwiched therebetween, and a liquid crystal element configured so that the alignment state of the liquid crystal changes concentrically around the optical axis when a voltage is applied. is there.
[0008]
According to this configuration, a predetermined refractive index distribution is given to the entire element in accordance with the alignment state of the liquid crystal that changes concentrically, and the focal point moves to exert the optical zoom function.
[0009]
According to a second aspect of the present invention, a liquid crystal element that is arranged on the optical axis together with a lens to form an optical zoom system, forms a refractive index distribution by applying a voltage, and exerts an optical zoom function. A plurality of electrodes facing each other with a liquid crystal sandwiched therebetween, and a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes, and the size along the radial direction when the electrodes are concentrically divided. Alternatively, there is provided a liquid crystal element which is formed by an arrangement pattern in which arrangement intervals or both of them are changed, and in which liquid crystals are non-uniformly aligned when a voltage is applied inside the non-electrode portion.
[0010]
According to this structure, a weak electric field is formed in the central portion of the plurality of non-electrode portions in the direction perpendicular to the electrodes, and an electric field is formed in the inclined direction at the end portions of the non-electrode portions. Since the liquid crystal molecules are non-uniformly aligned along the electric field distribution,

[0003]
A light refraction effect (lens effect) in which the refractive index continuously changes toward the periphery can be obtained. Since the size of the non-electrode portion or the arrangement interval is changed concentrically on the electrode, a predetermined refractive index distribution is given to the entire element, and the focus moves to exert the optical zoom function.
[0011]
According to the third aspect of the invention, the liquid crystal element is arranged on the optical axis together with a lens to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to exhibit an optical zoom function. , A plurality of electrodes facing each other across the liquid crystal, a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes, along a radial direction when the electrodes are concentrically divided. It is formed by an arrangement pattern in which the size and/or the arrangement interval are changed, and the inside of the non-electrode portion is configured so that the liquid crystal is non-uniformly aligned when a voltage is applied. Provided is a liquid crystal element in which linear electrodes are annularly arranged at a predetermined interval along the arrangement pattern that changes concentrically.
[0012]
According to this configuration, by changing the size or the arrangement interval of the non-electrode parts in a concentric manner as described above, a desired refractive index distribution can be obtained, and a plurality of linear electrodes are arranged in an annular shape. By further applying a voltage to the predetermined portion, the above refractive index distribution is further emphasized and the optical zoom function is improved.
[0013]
The fourth invention is that in the liquid crystal element according to the second invention or the third invention, the arrangement intervals of the plurality of non-electrode portions are irregular in each concentric region on the electrode. Characterize.
[0014]
According to this configuration, the distance between the adjacent non-electrode portions is irregular (random), so that the disturbance of the wavefront due to the optical interference effect is prevented.
[0015]
Further, a fifth invention is characterized in that, in the liquid crystal element according to the second invention or the third invention, the non-electrode portion has a circular shape or a pit shape.
[0016]
According to this structure, the shape of the non-electrode portion is optimized for the light flux passing through the element. Here, the pit shape means a shape in which one axis is longer than the other axis perpendicular to it, and for example, the longer axis is formed parallel to the rubbing direction of the liquid crystal or perpendicular to the rubbing direction. can do.
[0017]
Further, in the sixth aspect of the invention, the liquid crystal element is arranged on the optical axis together with the lens to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to exhibit an optical zoom function.

[0004]
A liquid crystal and a plurality of electrodes facing each other with the liquid crystal sandwiched therebetween, at least one of the electrodes being composed of a plurality of concentric circular regions having different resistance values, and the electrodes being different from each other. A plurality of linear electrodes for applying a voltage are arranged concentrically around the optical axis at predetermined intervals, and the linear electrodes are arranged when a voltage is applied to the plurality of linear electrodes. A liquid crystal configured such that the electrode acts as a resistance film, a voltage drop occurs between the plurality of linear electrodes, and the alignment state of the liquid crystal changes concentrically around the optical axis. Provide the element.
[0018]
According to this configuration, the applied voltage is continuously changed between the plurality of linear electrodes, and the alignment state of the liquid crystal is changed according to the voltage value, so that a predetermined refractive index distribution is formed over the entire element. , Optical zoom function is demonstrated.
[0019]
Further, in the liquid crystal element according to the sixth aspect of the invention, the resistance film on which the plurality of linear electrodes are arranged is composed of a plurality of regions having different resistance values.
[0020]
According to this structure, the voltage drop between the plurality of linear electrodes becomes curved.
[0021]
An eighth aspect of the invention is characterized in that, in the liquid crystal element according to any one of the second, third, and sixth aspects of the invention, when the optical zoom system is configured, the outside of a region through which a light beam passes is shielded.
[0022]
According to this configuration, diffused reflection from the outside of the area through which the light flux passes is blocked, and the image quality of the image is stabilized.
[0023]
Further, in the ninth invention, it is composed of two liquid crystal elements laminated in the thickness direction, and is arranged with a lens on the optical axis to form an optical zoom system, and a refractive index distribution is formed by applying a voltage to form an optical zoom system. A liquid crystal element having a double cell structure that exhibits a zoom function, wherein each of the liquid crystal elements is sandwiched between a pair of substrates having a common electrode formed on one side and a segment electrode formed on the other side, and the pair of substrates. And a plurality of non-electrode portions where no electrode material is present in the segment electrode, the size and/or the arrangement interval of the segment electrode being changed along the radial direction when the segment electrode is concentrically divided. The liquid crystal is formed in a disposition pattern so that the liquid crystal is non-uniformly aligned when a voltage is applied inside the non-electrode portion.

Claims (21)

  A liquid crystal element that is arranged on the optical axis together with a lens to form an optical zoom system, forms a refractive index distribution by applying a voltage, and exerts an optical zoom function. The liquid crystal element faces the liquid crystal with the liquid crystal interposed therebetween. And a plurality of electrodes for controlling the liquid crystal, wherein the alignment state of the liquid crystal changes concentrically around the optical axis when a voltage is applied.   A liquid crystal element that is arranged on the optical axis together with a lens to form an optical zoom system, forms a refractive index distribution by applying a voltage, and exerts an optical zoom function. The liquid crystal element faces the liquid crystal with the liquid crystal interposed therebetween. And a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes, the size or arrangement interval along the radial direction when the electrodes are divided into concentric circles or A liquid crystal element formed by arranging both of them so that the liquid crystal is nonuniformly aligned when a voltage is applied inside the non-electrode portion.   A liquid crystal element that is arranged on the optical axis together with a lens to form an optical zoom system, forms a refractive index distribution by applying a voltage, and exerts an optical zoom function. The liquid crystal element faces the liquid crystal with the liquid crystal interposed therebetween. And a plurality of non-electrode portions where no electrode material is present in at least one of the electrodes, the size or arrangement interval along the radial direction when the electrodes are divided into concentric circles or Both are formed by changing the arrangement pattern, and the liquid crystal is arranged to be non-uniformly aligned when a voltage is applied inside the non-electrode portion, and a plurality of linear electrodes to which different voltages are applied are formed into the concentric circles. A liquid crystal element which is annularly arranged at a predetermined interval along an arrangement pattern that changes to.   The liquid crystal element according to claim 2 or 3, wherein the arrangement intervals of the plurality of non-electrode portions are irregular in each concentric region on the electrode.   The liquid crystal element according to claim 2 or 3, wherein the non-electrode portion has a circular shape or a pit shape.   A liquid crystal element that is arranged on the optical axis together with a lens to form an optical zoom system, forms a refractive index distribution by applying a voltage, and exerts an optical zoom function. The liquid crystal element faces the liquid crystal with the liquid crystal interposed therebetween. A plurality of electrodes, and at least one of the plurality of electrodes is provided with a plurality of linear electrodes that apply different voltages concentrically around the optical axis at predetermined intervals. When a voltage is applied to the two linear electrodes, the electrodes on which the linear electrodes are arranged act as a resistance film, causing a voltage drop between the plurality of linear electrodes, and thereby aligning the liquid crystal. A liquid crystal element configured so that the state changes concentrically around the optical axis.   The liquid crystal element according to claim 6, wherein the electrode on which the plurality of linear electrodes are arranged is composed of a plurality of regions having different resistance values.   The liquid crystal element according to any one of claims 1 to 3, 6, and 7, wherein when the optical zoom system is configured, a liquid crystal element is shielded outside a region through which a light beam passes.   It is composed of two liquid crystal elements stacked in the thickness direction, and is arranged with a lens on the optical axis to form an optical zoom system. By applying a voltage, a refractive index distribution is formed and the double function is achieved. A liquid crystal element having a cell structure, wherein each of the liquid crystal elements includes a pair of substrates having a common electrode formed on one side and a segment electrode formed on the other side, and a liquid crystal sandwiched between the pair of substrates. In the electrode, a plurality of non-electrode parts where no electrode material is present are formed in an arrangement pattern in which the size or the arrangement interval or both of them are changed along the radial direction when the segment electrode is divided into concentric circles. Inside the non-electrode portion, the liquid crystal is arranged to be non-uniformly aligned when a voltage is applied, and a plurality of holes are formed in each of the pair of substrates in a thickness direction, and the common electrode is formed in the hole. And a terminal connected to any one of the segment electrodes, and an injection port for injecting liquid crystal is formed in one of the pair of substrates, which is a double cell structure liquid crystal element.   The liquid crystal device of the double cell structure according to claim 9, wherein the liquid crystal alignment directions of the two liquid crystal devices when no voltage is applied are orthogonal to each other.   The liquid crystal device having a double cell structure according to claim 9, wherein the substrate is formed in a quadrangular shape, the liquid crystal is sealed along a circular region through which a light flux of the substrate passes, and the liquid crystal is provided near a corner portion other than the circular region. A liquid crystal device having a double-cell structure, characterized in that an injection port and a terminal are provided.   The liquid crystal device having a double cell structure according to claim 10, wherein the substrate is formed in a quadrangular shape, the liquid crystal is sealed along a circular area through which the light flux of the substrate passes, and the liquid crystal is provided near a corner portion other than the circular area. A liquid crystal device having a double-cell structure, characterized in that an injection port and a terminal are provided.   The liquid crystal element having a double cell structure according to any one of claims 9 to 11, wherein terminals connected to a common electrode of each laminated liquid crystal element, terminals connected to a segment electrode of one liquid crystal element, and The terminals connected to the segment electrodes of the other liquid crystal element are connected to each other in the thickness direction, and are integrated into the terminals provided on the one substrate located outside the liquid crystal element of the double cell structure. Characteristic double cell structure liquid crystal element.   The liquid crystal element having a double cell structure according to claim 12, wherein terminals connected to a common electrode of each laminated liquid crystal element, terminals connected to a segment electrode of one liquid crystal element, and another liquid crystal element of the other liquid crystal element. The terminals connected to the segment electrodes are connected to each other in the thickness direction, and are integrated into the terminals provided on one substrate which is the outermost side of the liquid crystal element having the double cell structure. A liquid crystal device with a cell structure.   15. The liquid crystal element having a double cell structure according to claim 14, wherein a terminal connected to a segment electrode of one liquid crystal element and a terminal connected to a segment electrode of the other liquid crystal element are diagonal to each other on a rectangular substrate. A liquid crystal element having a double cell structure, characterized in that it is provided in the vicinity of a corner portion located at, and a terminal connected to the common electrode and a liquid crystal inlet are provided in the vicinity of the remaining corner portion.   The liquid crystal element having a double cell structure according to any one of claims 9 to 12, characterized in that the liquid crystal element having a double cell structure shields the outside of a region through which a light flux passes when an optical zoom system is configured.   A method of manufacturing a liquid crystal device having a double cell structure according to claim 15, wherein a substrate and a base material are provided with terminals and injection ports corresponding to a large number of liquid crystal devices, and a process of forming segment electrodes. And a step of combining another substrate having a common electrode formed with a terminal provided at a position facing the substrate having the terminals, the injection port, and the segment electrode formed thereon, and injecting liquid crystal from the injection port after the combination. A step, and a step of stacking after turning another set obtained by going through the same steps and rotating by 90 degrees with respect to a set in which a large number of liquid crystal elements manufactured through the above steps are arranged, And a step of dividing into a liquid crystal device having a double cell structure, and a method for manufacturing a liquid crystal device having a double cell structure.   A method of manufacturing a liquid crystal device having a double cell structure according to claim 15, wherein a substrate corresponding to a large number of liquid crystal devices is provided on a substrate as a base material, a segment electrode is formed, Of the substrate and the substrate on which the segment electrode is formed, a step of combining another substrate on which a terminal and an injection port are provided at a position facing each other and a common electrode is formed, and a step of injecting liquid crystal from the injection port after combination. A step in which another set obtained by going through the same steps is turned upside down and rotated by 90 degrees, and then stacked, with respect to a set in which a large number of liquid crystal elements arranged through the above steps are arranged; A method of manufacturing a liquid crystal device having a double cell structure, which comprises a step of dividing into a liquid crystal device having a heavy cell structure.   The manufacturing method according to claim 17 or 18, wherein a wiring for inspection commonly connected to each terminal is formed on the surface of the substrate, and another set is provided for a set in which a large number of liquid crystal elements are arranged. Of the double cell structure, characterized in that the inspection is performed by using the wiring at either or both of the steps before the step of stacking the liquid crystal and the step of dividing the liquid crystal element into individual double cell structures. Liquid crystal device manufacturing method.   The manufacturing method according to claim 17 or 18, wherein, when another set is stacked on a set in which a large number of liquid crystal elements are arranged, the set is closed in a vacuum so as to surround a circular region through which a light beam passes. A method of manufacturing a liquid crystal device having a double cell structure, characterized in that the liquid crystal device is laminated via a sealant provided.   The manufacturing method according to claim 17 or 18, wherein when a plurality of liquid crystal elements are arranged and another set is laminated, a part of the set is opened so as to surround a circular region through which a light flux passes in the atmosphere. A method of manufacturing a liquid crystal element having a double cell structure, which comprises laminating a sealing material provided in a state and an adhesive provided inside the sealing material.

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